Merge branch 'vim' into feat/rel-line-numbers

[vim_extended.git] / src / ops.c

/* vi:set ts=8 sts=4 sw=4:
 *
 * VIM - Vi IMproved    by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * ops.c: implementation of various operators: op_shift, op_delete, op_tilde,
 *        op_change, op_yank, do_put, do_join
 */

#include "vim.h"

/*
 * Number of registers.
 *      0 = unnamed register, for normal yanks and puts
 *   1..9 = registers '1' to '9', for deletes
 * 10..35 = registers 'a' to 'z'
 *     36 = delete register '-'
 *     37 = Selection register '*'. Only if FEAT_CLIPBOARD defined
 *     38 = Clipboard register '+'. Only if FEAT_CLIPBOARD and FEAT_X11 defined
 */
/*
 * Symbolic names for some registers.
 */
#define DELETION_REGISTER       36
#ifdef FEAT_CLIPBOARD
# define STAR_REGISTER          37
#  ifdef FEAT_X11
#   define PLUS_REGISTER        38
#  else
#   define PLUS_REGISTER        STAR_REGISTER       /* there is only one */
#  endif
#endif
#ifdef FEAT_DND
# define TILDE_REGISTER         (PLUS_REGISTER + 1)
#endif

#ifdef FEAT_CLIPBOARD
# ifdef FEAT_DND
#  define NUM_REGISTERS         (TILDE_REGISTER + 1)
# else
#  define NUM_REGISTERS         (PLUS_REGISTER + 1)
# endif
#else
# define NUM_REGISTERS          37
#endif

/*
 * Each yank register is an array of pointers to lines.
 */
static struct yankreg
{
    char_u      **y_array;      /* pointer to array of line pointers */
    linenr_T    y_size;         /* number of lines in y_array */
    char_u      y_type;         /* MLINE, MCHAR or MBLOCK */
#ifdef FEAT_VISUAL
    colnr_T     y_width;        /* only set if y_type == MBLOCK */
#endif
} y_regs[NUM_REGISTERS];

static struct yankreg   *y_current;         /* ptr to current yankreg */
static int              y_append;           /* TRUE when appending */
static struct yankreg   *y_previous = NULL; /* ptr to last written yankreg */

/*
 * structure used by block_prep, op_delete and op_yank for blockwise operators
 * also op_change, op_shift, op_insert, op_replace - AKelly
 */
struct block_def
{
    int         startspaces;    /* 'extra' cols of first char */
    int         endspaces;      /* 'extra' cols of first char */
    int         textlen;        /* chars in block */
    char_u      *textstart;     /* pointer to 1st char in block */
    colnr_T     textcol;        /* cols of chars (at least part.) in block */
    colnr_T     start_vcol;     /* start col of 1st char wholly inside block */
    colnr_T     end_vcol;       /* start col of 1st char wholly after block */
#ifdef FEAT_VISUALEXTRA
    int         is_short;       /* TRUE if line is too short to fit in block */
    int         is_MAX;         /* TRUE if curswant==MAXCOL when starting */
    int         is_oneChar;     /* TRUE if block within one character */
    int         pre_whitesp;    /* screen cols of ws before block */
    int         pre_whitesp_c;  /* chars of ws before block */
    colnr_T     end_char_vcols; /* number of vcols of post-block char */
#endif
    colnr_T     start_char_vcols; /* number of vcols of pre-block char */
};

#ifdef FEAT_VISUALEXTRA
static void shift_block __ARGS((oparg_T *oap, int amount));
static void block_insert __ARGS((oparg_T *oap, char_u *s, int b_insert, struct block_def*bdp));
#endif
static int      stuff_yank __ARGS((int, char_u *));
static void     put_reedit_in_typebuf __ARGS((int silent));
static int      put_in_typebuf __ARGS((char_u *s, int esc, int colon,
                                                                 int silent));
static void     stuffescaped __ARGS((char_u *arg, int literally));
#ifdef FEAT_MBYTE
static void     mb_adjust_opend __ARGS((oparg_T *oap));
#endif
static void     free_yank __ARGS((long));
static void     free_yank_all __ARGS((void));
static int      yank_copy_line __ARGS((struct block_def *bd, long y_idx));
#ifdef FEAT_CLIPBOARD
static void     copy_yank_reg __ARGS((struct yankreg *reg));
# if defined(FEAT_VISUAL) || defined(FEAT_EVAL)
static void     may_set_selection __ARGS((void));
# endif
#endif
static void     dis_msg __ARGS((char_u *p, int skip_esc));
#ifdef FEAT_VISUAL
static void     block_prep __ARGS((oparg_T *oap, struct block_def *, linenr_T, int));
#endif
#if defined(FEAT_CLIPBOARD) || defined(FEAT_EVAL)
static void     str_to_reg __ARGS((struct yankreg *y_ptr, int type, char_u *str, long len, long blocklen));
#endif
static int      ends_in_white __ARGS((linenr_T lnum));
#ifdef FEAT_COMMENTS
static int      same_leader __ARGS((linenr_T lnum, int, char_u *, int, char_u *));
static int      fmt_check_par __ARGS((linenr_T, int *, char_u **, int do_comments));
#else
static int      fmt_check_par __ARGS((linenr_T));
#endif

/*
 * The names of operators.
 * IMPORTANT: Index must correspond with defines in vim.h!!!
 * The third field indicates whether the operator always works on lines.
 */
static char opchars[][3] =
{
    {NUL, NUL, FALSE},  /* OP_NOP */
    {'d', NUL, FALSE},  /* OP_DELETE */
    {'y', NUL, FALSE},  /* OP_YANK */
    {'c', NUL, FALSE},  /* OP_CHANGE */
    {'<', NUL, TRUE},   /* OP_LSHIFT */
    {'>', NUL, TRUE},   /* OP_RSHIFT */
    {'!', NUL, TRUE},   /* OP_FILTER */
    {'g', '~', FALSE},  /* OP_TILDE */
    {'=', NUL, TRUE},   /* OP_INDENT */
    {'g', 'q', TRUE},   /* OP_FORMAT */
    {':', NUL, TRUE},   /* OP_COLON */
    {'g', 'U', FALSE},  /* OP_UPPER */
    {'g', 'u', FALSE},  /* OP_LOWER */
    {'J', NUL, TRUE},   /* DO_JOIN */
    {'g', 'J', TRUE},   /* DO_JOIN_NS */
    {'g', '?', FALSE},  /* OP_ROT13 */
    {'r', NUL, FALSE},  /* OP_REPLACE */
    {'I', NUL, FALSE},  /* OP_INSERT */
    {'A', NUL, FALSE},  /* OP_APPEND */
    {'z', 'f', TRUE},   /* OP_FOLD */
    {'z', 'o', TRUE},   /* OP_FOLDOPEN */
    {'z', 'O', TRUE},   /* OP_FOLDOPENREC */
    {'z', 'c', TRUE},   /* OP_FOLDCLOSE */
    {'z', 'C', TRUE},   /* OP_FOLDCLOSEREC */
    {'z', 'd', TRUE},   /* OP_FOLDDEL */
    {'z', 'D', TRUE},   /* OP_FOLDDELREC */
    {'g', 'w', TRUE},   /* OP_FORMAT2 */
    {'g', '@', FALSE},  /* OP_FUNCTION */
};

/*
 * Translate a command name into an operator type.
 * Must only be called with a valid operator name!
 */
    int
get_op_type(char1, char2)
    int         char1;
    int         char2;
{
    int         i;

    if (char1 == 'r')           /* ignore second character */
        return OP_REPLACE;
    if (char1 == '~')           /* when tilde is an operator */
        return OP_TILDE;
    for (i = 0; ; ++i)
        if (opchars[i][0] == char1 && opchars[i][1] == char2)
            break;
    return i;
}

#if defined(FEAT_VISUAL) || defined(PROTO)
/*
 * Return TRUE if operator "op" always works on whole lines.
 */
    int
op_on_lines(op)
    int op;
{
    return opchars[op][2];
}
#endif

/*
 * Get first operator command character.
 * Returns 'g' or 'z' if there is another command character.
 */
    int
get_op_char(optype)
    int         optype;
{
    return opchars[optype][0];
}

/*
 * Get second operator command character.
 */
    int
get_extra_op_char(optype)
    int         optype;
{
    return opchars[optype][1];
}

/*
 * op_shift - handle a shift operation
 */
    void
op_shift(oap, curs_top, amount)
    oparg_T         *oap;
    int             curs_top;
    int             amount;
{
    long            i;
    int             first_char;
    char_u          *s;
#ifdef FEAT_VISUAL
    int             block_col = 0;
#endif

    if (u_save((linenr_T)(oap->start.lnum - 1),
                                       (linenr_T)(oap->end.lnum + 1)) == FAIL)
        return;

#ifdef FEAT_VISUAL
    if (oap->block_mode)
        block_col = curwin->w_cursor.col;
#endif

    for (i = oap->line_count; --i >= 0; )
    {
        first_char = *ml_get_curline();
        if (first_char == NUL)                          /* empty line */
            curwin->w_cursor.col = 0;
#ifdef FEAT_VISUALEXTRA
        else if (oap->block_mode)
            shift_block(oap, amount);
#endif
        else
            /* Move the line right if it doesn't start with '#', 'smartindent'
             * isn't set or 'cindent' isn't set or '#' isn't in 'cino'. */
#if defined(FEAT_SMARTINDENT) || defined(FEAT_CINDENT)
            if (first_char != '#' || !preprocs_left())
#endif
        {
            shift_line(oap->op_type == OP_LSHIFT, p_sr, amount, FALSE);
        }
        ++curwin->w_cursor.lnum;
    }

    changed_lines(oap->start.lnum, 0, oap->end.lnum + 1, 0L);

#ifdef FEAT_VISUAL
    if (oap->block_mode)
    {
        curwin->w_cursor.lnum = oap->start.lnum;
        curwin->w_cursor.col = block_col;
    }
    else
#endif
        if (curs_top)       /* put cursor on first line, for ">>" */
    {
        curwin->w_cursor.lnum = oap->start.lnum;
        beginline(BL_SOL | BL_FIX);   /* shift_line() may have set cursor.col */
    }
    else
        --curwin->w_cursor.lnum;        /* put cursor on last line, for ":>" */

    if (oap->line_count > p_report)
    {
        if (oap->op_type == OP_RSHIFT)
            s = (char_u *)">";
        else
            s = (char_u *)"<";
        if (oap->line_count == 1)
        {
            if (amount == 1)
                sprintf((char *)IObuff, _("1 line %sed 1 time"), s);
            else
                sprintf((char *)IObuff, _("1 line %sed %d times"), s, amount);
        }
        else
        {
            if (amount == 1)
                sprintf((char *)IObuff, _("%ld lines %sed 1 time"),
                                                          oap->line_count, s);
            else
                sprintf((char *)IObuff, _("%ld lines %sed %d times"),
                                                  oap->line_count, s, amount);
        }
        msg(IObuff);
    }

    /*
     * Set "'[" and "']" marks.
     */
    curbuf->b_op_start = oap->start;
    curbuf->b_op_end.lnum = oap->end.lnum;
    curbuf->b_op_end.col = (colnr_T)STRLEN(ml_get(oap->end.lnum));
    if (curbuf->b_op_end.col > 0)
        --curbuf->b_op_end.col;
}

/*
 * shift the current line one shiftwidth left (if left != 0) or right
 * leaves cursor on first blank in the line
 */
    void
shift_line(left, round, amount, call_changed_bytes)
    int left;
    int round;
    int amount;
    int call_changed_bytes;     /* call changed_bytes() */
{
    int         count;
    int         i, j;
    int         p_sw = (int)curbuf->b_p_sw;

    count = get_indent();       /* get current indent */

    if (round)                  /* round off indent */
    {
        i = count / p_sw;       /* number of p_sw rounded down */
        j = count % p_sw;       /* extra spaces */
        if (j && left)          /* first remove extra spaces */
            --amount;
        if (left)
        {
            i -= amount;
            if (i < 0)
                i = 0;
        }
        else
            i += amount;
        count = i * p_sw;
    }
    else                /* original vi indent */
    {
        if (left)
        {
            count -= p_sw * amount;
            if (count < 0)
                count = 0;
        }
        else
            count += p_sw * amount;
    }

    /* Set new indent */
#ifdef FEAT_VREPLACE
    if (State & VREPLACE_FLAG)
        change_indent(INDENT_SET, count, FALSE, NUL, call_changed_bytes);
    else
#endif
        (void)set_indent(count, call_changed_bytes ? SIN_CHANGED : 0);
}

#if defined(FEAT_VISUALEXTRA) || defined(PROTO)
/*
 * Shift one line of the current block one shiftwidth right or left.
 * Leaves cursor on first character in block.
 */
    static void
shift_block(oap, amount)
    oparg_T     *oap;
    int         amount;
{
    int                 left = (oap->op_type == OP_LSHIFT);
    int                 oldstate = State;
    int                 total, split;
    char_u              *newp, *oldp, *midp, *ptr;
    int                 oldcol = curwin->w_cursor.col;
    int                 p_sw = (int)curbuf->b_p_sw;
    int                 p_ts = (int)curbuf->b_p_ts;
    struct block_def    bd;
    int                 internal = 0;
    int                 incr;
    colnr_T             vcol, col = 0, ws_vcol;
    int                 i = 0, j = 0;
    int                 len;

#ifdef FEAT_RIGHTLEFT
    int                 old_p_ri = p_ri;

    p_ri = 0;                   /* don't want revins in ident */
#endif

    State = INSERT;             /* don't want REPLACE for State */
    block_prep(oap, &bd, curwin->w_cursor.lnum, TRUE);
    if (bd.is_short)
        return;

    /* total is number of screen columns to be inserted/removed */
    total = amount * p_sw;
    oldp = ml_get_curline();

    if (!left)
    {
        /*
         *  1. Get start vcol
         *  2. Total ws vcols
         *  3. Divvy into TABs & spp
         *  4. Construct new string
         */
        total += bd.pre_whitesp; /* all virtual WS upto & incl a split TAB */
        ws_vcol = bd.start_vcol - bd.pre_whitesp;
        if (bd.startspaces)
        {
#ifdef FEAT_MBYTE
            if (has_mbyte)
                bd.textstart += (*mb_ptr2len)(bd.textstart);
#endif
            ++bd.textstart;
        }
        for ( ; vim_iswhite(*bd.textstart); )
        {
            incr = lbr_chartabsize_adv(&bd.textstart, (colnr_T)(bd.start_vcol));
            total += incr;
            bd.start_vcol += incr;
        }
        /* OK, now total=all the VWS reqd, and textstart points at the 1st
         * non-ws char in the block. */
        if (!curbuf->b_p_et)
            i = ((ws_vcol % p_ts) + total) / p_ts; /* number of tabs */
        if (i)
            j = ((ws_vcol % p_ts) + total) % p_ts; /* number of spp */
        else
            j = total;
        /* if we're splitting a TAB, allow for it */
        bd.textcol -= bd.pre_whitesp_c - (bd.startspaces != 0);
        len = (int)STRLEN(bd.textstart) + 1;
        newp = alloc_check((unsigned)(bd.textcol + i + j + len));
        if (newp == NULL)
            return;
        vim_memset(newp, NUL, (size_t)(bd.textcol + i + j + len));
        mch_memmove(newp, oldp, (size_t)bd.textcol);
        copy_chars(newp + bd.textcol, (size_t)i, TAB);
        copy_spaces(newp + bd.textcol + i, (size_t)j);
        /* the end */
        mch_memmove(newp + bd.textcol + i + j, bd.textstart, (size_t)len);
    }
    else /* left */
    {
        vcol = oap->start_vcol;
        /* walk vcol past ws to be removed */
        for (midp = oldp + bd.textcol;
              vcol < (oap->start_vcol + total) && vim_iswhite(*midp); )
        {
            incr = lbr_chartabsize_adv(&midp, (colnr_T)vcol);
            vcol += incr;
        }
        /* internal is the block-internal ws replacing a split TAB */
        if (vcol > (oap->start_vcol + total))
        {
            /* we have to split the TAB *(midp-1) */
            internal = vcol - (oap->start_vcol + total);
        }
        /* if 'expandtab' is not set, use TABs */

        split = bd.startspaces + internal;
        if (split > 0)
        {
            if (!curbuf->b_p_et)
            {
                for (ptr = oldp, col = 0; ptr < oldp+bd.textcol; )
                    col += lbr_chartabsize_adv(&ptr, (colnr_T)col);

                /* col+1 now equals the start col of the first char of the
                 * block (may be < oap.start_vcol if we're splitting a TAB) */
                i = ((col % p_ts) + split) / p_ts; /* number of tabs */
            }
            if (i)
                j = ((col % p_ts) + split) % p_ts; /* number of spp */
            else
                j = split;
        }

        newp = alloc_check(bd.textcol + i + j + (unsigned)STRLEN(midp) + 1);
        if (newp == NULL)
            return;
        vim_memset(newp, NUL, (size_t)(bd.textcol + i + j + STRLEN(midp) + 1));

        /* copy first part we want to keep */
        mch_memmove(newp, oldp, (size_t)bd.textcol);
        /* Now copy any TABS and spp to ensure correct alignment! */
        while (vim_iswhite(*midp))
        {
            if (*midp == TAB)
                i++;
            else /*space */
                j++;
            midp++;
        }
        /* We might have an extra TAB worth of spp now! */
        if (j / p_ts && !curbuf->b_p_et)
        {
            i++;
            j -= p_ts;
        }
        copy_chars(newp + bd.textcol, (size_t)i, TAB);
        copy_spaces(newp + bd.textcol + i, (size_t)j);

        /* the end */
        STRMOVE(newp + STRLEN(newp), midp);
    }
    /* replace the line */
    ml_replace(curwin->w_cursor.lnum, newp, FALSE);
    changed_bytes(curwin->w_cursor.lnum, (colnr_T)bd.textcol);
    State = oldstate;
    curwin->w_cursor.col = oldcol;
#ifdef FEAT_RIGHTLEFT
    p_ri = old_p_ri;
#endif
}
#endif

#ifdef FEAT_VISUALEXTRA
/*
 * Insert string "s" (b_insert ? before : after) block :AKelly
 * Caller must prepare for undo.
 */
    static void
block_insert(oap, s, b_insert, bdp)
    oparg_T             *oap;
    char_u              *s;
    int                 b_insert;
    struct block_def    *bdp;
{
    int         p_ts;
    int         count = 0;      /* extra spaces to replace a cut TAB */
    int         spaces = 0;     /* non-zero if cutting a TAB */
    colnr_T     offset;         /* pointer along new line */
    unsigned    s_len;          /* STRLEN(s) */
    char_u      *newp, *oldp;   /* new, old lines */
    linenr_T    lnum;           /* loop var */
    int         oldstate = State;

    State = INSERT;             /* don't want REPLACE for State */
    s_len = (unsigned)STRLEN(s);

    for (lnum = oap->start.lnum + 1; lnum <= oap->end.lnum; lnum++)
    {
        block_prep(oap, bdp, lnum, TRUE);
        if (bdp->is_short && b_insert)
            continue;   /* OP_INSERT, line ends before block start */

        oldp = ml_get(lnum);

        if (b_insert)
        {
            p_ts = bdp->start_char_vcols;
            spaces = bdp->startspaces;
            if (spaces != 0)
                count = p_ts - 1; /* we're cutting a TAB */
            offset = bdp->textcol;
        }
        else /* append */
        {
            p_ts = bdp->end_char_vcols;
            if (!bdp->is_short) /* spaces = padding after block */
            {
                spaces = (bdp->endspaces ? p_ts - bdp->endspaces : 0);
                if (spaces != 0)
                    count = p_ts - 1; /* we're cutting a TAB */
                offset = bdp->textcol + bdp->textlen - (spaces != 0);
            }
            else /* spaces = padding to block edge */
            {
                /* if $ used, just append to EOL (ie spaces==0) */
                if (!bdp->is_MAX)
                    spaces = (oap->end_vcol - bdp->end_vcol) + 1;
                count = spaces;
                offset = bdp->textcol + bdp->textlen;
            }
        }

        newp = alloc_check((unsigned)(STRLEN(oldp)) + s_len + count + 1);
        if (newp == NULL)
            continue;

        /* copy up to shifted part */
        mch_memmove(newp, oldp, (size_t)(offset));
        oldp += offset;

        /* insert pre-padding */
        copy_spaces(newp + offset, (size_t)spaces);

        /* copy the new text */
        mch_memmove(newp + offset + spaces, s, (size_t)s_len);
        offset += s_len;

        if (spaces && !bdp->is_short)
        {
            /* insert post-padding */
            copy_spaces(newp + offset + spaces, (size_t)(p_ts - spaces));
            /* We're splitting a TAB, don't copy it. */
            oldp++;
            /* We allowed for that TAB, remember this now */
            count++;
        }

        if (spaces > 0)
            offset += count;
        STRMOVE(newp + offset, oldp);

        ml_replace(lnum, newp, FALSE);

        if (lnum == oap->end.lnum)
        {
            /* Set "']" mark to the end of the block instead of the end of
             * the insert in the first line.  */
            curbuf->b_op_end.lnum = oap->end.lnum;
            curbuf->b_op_end.col = offset;
        }
    } /* for all lnum */

    changed_lines(oap->start.lnum + 1, 0, oap->end.lnum + 1, 0L);

    State = oldstate;
}
#endif

#if defined(FEAT_LISP) || defined(FEAT_CINDENT) || defined(PROTO)
/*
 * op_reindent - handle reindenting a block of lines.
 */
    void
op_reindent(oap, how)
    oparg_T     *oap;
    int         (*how) __ARGS((void));
{
    long        i;
    char_u      *l;
    int         count;
    linenr_T    first_changed = 0;
    linenr_T    last_changed = 0;
    linenr_T    start_lnum = curwin->w_cursor.lnum;

    /* Don't even try when 'modifiable' is off. */
    if (!curbuf->b_p_ma)
    {
        EMSG(_(e_modifiable));
        return;
    }

    for (i = oap->line_count; --i >= 0 && !got_int; )
    {
        /* it's a slow thing to do, so give feedback so there's no worry that
         * the computer's just hung. */

        if (i > 1
                && (i % 50 == 0 || i == oap->line_count - 1)
                && oap->line_count > p_report)
            smsg((char_u *)_("%ld lines to indent... "), i);

        /*
         * Be vi-compatible: For lisp indenting the first line is not
         * indented, unless there is only one line.
         */
#ifdef FEAT_LISP
        if (i != oap->line_count - 1 || oap->line_count == 1
                                                    || how != get_lisp_indent)
#endif
        {
            l = skipwhite(ml_get_curline());
            if (*l == NUL)                  /* empty or blank line */
                count = 0;
            else
                count = how();              /* get the indent for this line */

            if (set_indent(count, SIN_UNDO))
            {
                /* did change the indent, call changed_lines() later */
                if (first_changed == 0)
                    first_changed = curwin->w_cursor.lnum;
                last_changed = curwin->w_cursor.lnum;
            }
        }
        ++curwin->w_cursor.lnum;
        curwin->w_cursor.col = 0;  /* make sure it's valid */
    }

    /* put cursor on first non-blank of indented line */
    curwin->w_cursor.lnum = start_lnum;
    beginline(BL_SOL | BL_FIX);

    /* Mark changed lines so that they will be redrawn.  When Visual
     * highlighting was present, need to continue until the last line.  When
     * there is no change still need to remove the Visual highlighting. */
    if (last_changed != 0)
        changed_lines(first_changed, 0,
#ifdef FEAT_VISUAL
                oap->is_VIsual ? start_lnum + oap->line_count :
#endif
                last_changed + 1, 0L);
#ifdef FEAT_VISUAL
    else if (oap->is_VIsual)
        redraw_curbuf_later(INVERTED);
#endif

    if (oap->line_count > p_report)
    {
        i = oap->line_count - (i + 1);
        if (i == 1)
            MSG(_("1 line indented "));
        else
            smsg((char_u *)_("%ld lines indented "), i);
    }
    /* set '[ and '] marks */
    curbuf->b_op_start = oap->start;
    curbuf->b_op_end = oap->end;
}
#endif /* defined(FEAT_LISP) || defined(FEAT_CINDENT) */

#if defined(FEAT_EVAL) || defined(PROTO)
/*
 * Keep the last expression line here, for repeating.
 */
static char_u   *expr_line = NULL;

/*
 * Get an expression for the "\"=expr1" or "CTRL-R =expr1"
 * Returns '=' when OK, NUL otherwise.
 */
    int
get_expr_register()
{
    char_u      *new_line;

    new_line = getcmdline('=', 0L, 0);
    if (new_line == NULL)
        return NUL;
    if (*new_line == NUL)       /* use previous line */
        vim_free(new_line);
    else
        set_expr_line(new_line);
    return '=';
}

/*
 * Set the expression for the '=' register.
 * Argument must be an allocated string.
 */
    void
set_expr_line(new_line)
    char_u      *new_line;
{
    vim_free(expr_line);
    expr_line = new_line;
}

/*
 * Get the result of the '=' register expression.
 * Returns a pointer to allocated memory, or NULL for failure.
 */
    char_u *
get_expr_line()
{
    char_u      *expr_copy;
    char_u      *rv;
    static int  nested = 0;

    if (expr_line == NULL)
        return NULL;

    /* Make a copy of the expression, because evaluating it may cause it to be
     * changed. */
    expr_copy = vim_strsave(expr_line);
    if (expr_copy == NULL)
        return NULL;

    /* When we are invoked recursively limit the evaluation to 10 levels.
     * Then return the string as-is. */
    if (nested >= 10)
        return expr_copy;

    ++nested;
    rv = eval_to_string(expr_copy, NULL, TRUE);
    --nested;
    vim_free(expr_copy);
    return rv;
}

/*
 * Get the '=' register expression itself, without evaluating it.
 */
    char_u *
get_expr_line_src()
{
    if (expr_line == NULL)
        return NULL;
    return vim_strsave(expr_line);
}
#endif /* FEAT_EVAL */

/*
 * Check if 'regname' is a valid name of a yank register.
 * Note: There is no check for 0 (default register), caller should do this
 */
    int
valid_yank_reg(regname, writing)
    int     regname;
    int     writing;        /* if TRUE check for writable registers */
{
    if (       (regname > 0 && ASCII_ISALNUM(regname))
            || (!writing && vim_strchr((char_u *)
#ifdef FEAT_EVAL
                                    "/.%#:="
#else
                                    "/.%#:"
#endif
                                        , regname) != NULL)
            || regname == '"'
            || regname == '-'
            || regname == '_'
#ifdef FEAT_CLIPBOARD
            || regname == '*'
            || regname == '+'
#endif
#ifdef FEAT_DND
            || (!writing && regname == '~')
#endif
                                                        )
        return TRUE;
    return FALSE;
}

/*
 * Set y_current and y_append, according to the value of "regname".
 * Cannot handle the '_' register.
 * Must only be called with a valid register name!
 *
 * If regname is 0 and writing, use register 0
 * If regname is 0 and reading, use previous register
 */
    void
get_yank_register(regname, writing)
    int     regname;
    int     writing;
{
    int     i;

    y_append = FALSE;
    if ((regname == 0 || regname == '"') && !writing && y_previous != NULL)
    {
        y_current = y_previous;
        return;
    }
    i = regname;
    if (VIM_ISDIGIT(i))
        i -= '0';
    else if (ASCII_ISLOWER(i))
        i = CharOrdLow(i) + 10;
    else if (ASCII_ISUPPER(i))
    {
        i = CharOrdUp(i) + 10;
        y_append = TRUE;
    }
    else if (regname == '-')
        i = DELETION_REGISTER;
#ifdef FEAT_CLIPBOARD
    /* When selection is not available, use register 0 instead of '*' */
    else if (clip_star.available && regname == '*')
        i = STAR_REGISTER;
    /* When clipboard is not available, use register 0 instead of '+' */
    else if (clip_plus.available && regname == '+')
        i = PLUS_REGISTER;
#endif
#ifdef FEAT_DND
    else if (!writing && regname == '~')
        i = TILDE_REGISTER;
#endif
    else                /* not 0-9, a-z, A-Z or '-': use register 0 */
        i = 0;
    y_current = &(y_regs[i]);
    if (writing)        /* remember the register we write into for do_put() */
        y_previous = y_current;
}

#if defined(FEAT_CLIPBOARD) || defined(PROTO)
/*
 * When "regname" is a clipboard register, obtain the selection.  If it's not
 * available return zero, otherwise return "regname".
 */
    int
may_get_selection(regname)
    int regname;
{
    if (regname == '*')
    {
        if (!clip_star.available)
            regname = 0;
        else
            clip_get_selection(&clip_star);
    }
    else if (regname == '+')
    {
        if (!clip_plus.available)
            regname = 0;
        else
            clip_get_selection(&clip_plus);
    }
    return regname;
}
#endif

#if defined(FEAT_VISUAL) || defined(PROTO)
/*
 * Obtain the contents of a "normal" register. The register is made empty.
 * The returned pointer has allocated memory, use put_register() later.
 */
    void *
get_register(name, copy)
    int         name;
    int         copy;   /* make a copy, if FALSE make register empty. */
{
    struct yankreg      *reg;
    int                 i;

#ifdef FEAT_CLIPBOARD
    /* When Visual area changed, may have to update selection.  Obtain the
     * selection too. */
    if (name == '*' && clip_star.available)
    {
        if (clip_isautosel())
            clip_update_selection();
        may_get_selection(name);
    }
#endif

    get_yank_register(name, 0);
    reg = (struct yankreg *)alloc((unsigned)sizeof(struct yankreg));
    if (reg != NULL)
    {
        *reg = *y_current;
        if (copy)
        {
            /* If we run out of memory some or all of the lines are empty. */
            if (reg->y_size == 0)
                reg->y_array = NULL;
            else
                reg->y_array = (char_u **)alloc((unsigned)(sizeof(char_u *)
                                                              * reg->y_size));
            if (reg->y_array != NULL)
            {
                for (i = 0; i < reg->y_size; ++i)
                    reg->y_array[i] = vim_strsave(y_current->y_array[i]);
            }
        }
        else
            y_current->y_array = NULL;
    }
    return (void *)reg;
}

/*
 * Put "reg" into register "name".  Free any previous contents and "reg".
 */
    void
put_register(name, reg)
    int         name;
    void        *reg;
{
    get_yank_register(name, 0);
    free_yank_all();
    *y_current = *(struct yankreg *)reg;
    vim_free(reg);

# ifdef FEAT_CLIPBOARD
    /* Send text written to clipboard register to the clipboard. */
    may_set_selection();
# endif
}
#endif

#if defined(FEAT_MOUSE) || defined(PROTO)
/*
 * return TRUE if the current yank register has type MLINE
 */
    int
yank_register_mline(regname)
    int     regname;
{
    if (regname != 0 && !valid_yank_reg(regname, FALSE))
        return FALSE;
    if (regname == '_')         /* black hole is always empty */
        return FALSE;
    get_yank_register(regname, FALSE);
    return (y_current->y_type == MLINE);
}
#endif

/*
 * Start or stop recording into a yank register.
 *
 * Return FAIL for failure, OK otherwise.
 */
    int
do_record(c)
    int c;
{
    char_u          *p;
    static int      regname;
    struct yankreg  *old_y_previous, *old_y_current;
    int             retval;

    if (Recording == FALSE)         /* start recording */
    {
                        /* registers 0-9, a-z and " are allowed */
        if (c < 0 || (!ASCII_ISALNUM(c) && c != '"'))
            retval = FAIL;
        else
        {
            Recording = TRUE;
            showmode();
            regname = c;
            retval = OK;
        }
    }
    else                            /* stop recording */
    {
        /*
         * Get the recorded key hits.  K_SPECIAL and CSI will be escaped, this
         * needs to be removed again to put it in a register.  exec_reg then
         * adds the escaping back later.
         */
        Recording = FALSE;
        MSG("");
        p = get_recorded();
        if (p == NULL)
            retval = FAIL;
        else
        {
            /* Remove escaping for CSI and K_SPECIAL in multi-byte chars. */
            vim_unescape_csi(p);

            /*
             * We don't want to change the default register here, so save and
             * restore the current register name.
             */
            old_y_previous = y_previous;
            old_y_current = y_current;

            retval = stuff_yank(regname, p);

            y_previous = old_y_previous;
            y_current = old_y_current;
        }
    }
    return retval;
}

/*
 * Stuff string "p" into yank register "regname" as a single line (append if
 * uppercase).  "p" must have been alloced.
 *
 * return FAIL for failure, OK otherwise
 */
    static int
stuff_yank(regname, p)
    int         regname;
    char_u      *p;
{
    char_u      *lp;
    char_u      **pp;

    /* check for read-only register */
    if (regname != 0 && !valid_yank_reg(regname, TRUE))
    {
        vim_free(p);
        return FAIL;
    }
    if (regname == '_')             /* black hole: don't do anything */
    {
        vim_free(p);
        return OK;
    }
    get_yank_register(regname, TRUE);
    if (y_append && y_current->y_array != NULL)
    {
        pp = &(y_current->y_array[y_current->y_size - 1]);
        lp = lalloc((long_u)(STRLEN(*pp) + STRLEN(p) + 1), TRUE);
        if (lp == NULL)
        {
            vim_free(p);
            return FAIL;
        }
        STRCPY(lp, *pp);
        STRCAT(lp, p);
        vim_free(p);
        vim_free(*pp);
        *pp = lp;
    }
    else
    {
        free_yank_all();
        if ((y_current->y_array =
                        (char_u **)alloc((unsigned)sizeof(char_u *))) == NULL)
        {
            vim_free(p);
            return FAIL;
        }
        y_current->y_array[0] = p;
        y_current->y_size = 1;
        y_current->y_type = MCHAR;  /* used to be MLINE, why? */
    }
    return OK;
}

/*
 * execute a yank register: copy it into the stuff buffer
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_execreg(regname, colon, addcr, silent)
    int     regname;
    int     colon;              /* insert ':' before each line */
    int     addcr;              /* always add '\n' to end of line */
    int     silent;             /* set "silent" flag in typeahead buffer */
{
    static int  lastc = NUL;
    long        i;
    char_u      *p;
    int         retval = OK;
    int         remap;

    if (regname == '@')                 /* repeat previous one */
    {
        if (lastc == NUL)
        {
            EMSG(_("E748: No previously used register"));
            return FAIL;
        }
        regname = lastc;
    }
                                        /* check for valid regname */
    if (regname == '%' || regname == '#' || !valid_yank_reg(regname, FALSE))
    {
        emsg_invreg(regname);
        return FAIL;
    }
    lastc = regname;

#ifdef FEAT_CLIPBOARD
    regname = may_get_selection(regname);
#endif

    if (regname == '_')                 /* black hole: don't stuff anything */
        return OK;

#ifdef FEAT_CMDHIST
    if (regname == ':')                 /* use last command line */
    {
        if (last_cmdline == NULL)
        {
            EMSG(_(e_nolastcmd));
            return FAIL;
        }
        vim_free(new_last_cmdline); /* don't keep the cmdline containing @: */
        new_last_cmdline = NULL;
        /* Escape all control characters with a CTRL-V */
        p = vim_strsave_escaped_ext(last_cmdline,
                (char_u *)"\001\002\003\004\005\006\007\010\011\012\013\014\015\016\017\020\021\022\023\024\025\026\027\030\031\032\033\034\035\036\037", Ctrl_V, FALSE);
        if (p != NULL)
        {
            /* When in Visual mode "'<,'>" will be prepended to the command.
             * Remove it when it's already there. */
            if (VIsual_active && STRNCMP(p, "'<,'>", 5) == 0)
                retval = put_in_typebuf(p + 5, TRUE, TRUE, silent);
            else
                retval = put_in_typebuf(p, TRUE, TRUE, silent);
        }
        vim_free(p);
    }
#endif
#ifdef FEAT_EVAL
    else if (regname == '=')
    {
        p = get_expr_line();
        if (p == NULL)
            return FAIL;
        retval = put_in_typebuf(p, TRUE, colon, silent);
        vim_free(p);
    }
#endif
    else if (regname == '.')            /* use last inserted text */
    {
        p = get_last_insert_save();
        if (p == NULL)
        {
            EMSG(_(e_noinstext));
            return FAIL;
        }
        retval = put_in_typebuf(p, FALSE, colon, silent);
        vim_free(p);
    }
    else
    {
        get_yank_register(regname, FALSE);
        if (y_current->y_array == NULL)
            return FAIL;

        /* Disallow remaping for ":@r". */
        remap = colon ? REMAP_NONE : REMAP_YES;

        /*
         * Insert lines into typeahead buffer, from last one to first one.
         */
        put_reedit_in_typebuf(silent);
        for (i = y_current->y_size; --i >= 0; )
        {
            char_u *escaped;

            /* insert NL between lines and after last line if type is MLINE */
            if (y_current->y_type == MLINE || i < y_current->y_size - 1
                                                                     || addcr)
            {
                if (ins_typebuf((char_u *)"\n", remap, 0, TRUE, silent) == FAIL)
                    return FAIL;
            }
            escaped = vim_strsave_escape_csi(y_current->y_array[i]);
            if (escaped == NULL)
                return FAIL;
            retval = ins_typebuf(escaped, remap, 0, TRUE, silent);
            vim_free(escaped);
            if (retval == FAIL)
                return FAIL;
            if (colon && ins_typebuf((char_u *)":", remap, 0, TRUE, silent)
                                                                      == FAIL)
                return FAIL;
        }
        Exec_reg = TRUE;        /* disable the 'q' command */
    }
    return retval;
}

/*
 * If "restart_edit" is not zero, put it in the typeahead buffer, so that it's
 * used only after other typeahead has been processed.
 */
    static void
put_reedit_in_typebuf(silent)
    int         silent;
{
    char_u      buf[3];

    if (restart_edit != NUL)
    {
        if (restart_edit == 'V')
        {
            buf[0] = 'g';
            buf[1] = 'R';
            buf[2] = NUL;
        }
        else
        {
            buf[0] = restart_edit == 'I' ? 'i' : restart_edit;
            buf[1] = NUL;
        }
        if (ins_typebuf(buf, REMAP_NONE, 0, TRUE, silent) == OK)
            restart_edit = NUL;
    }
}

    static int
put_in_typebuf(s, esc, colon, silent)
    char_u      *s;
    int         esc;        /* Escape CSI characters */
    int         colon;      /* add ':' before the line */
    int         silent;
{
    int         retval = OK;

    put_reedit_in_typebuf(silent);
    if (colon)
        retval = ins_typebuf((char_u *)"\n", REMAP_YES, 0, TRUE, silent);
    if (retval == OK)
    {
        char_u  *p;

        if (esc)
            p = vim_strsave_escape_csi(s);
        else
            p = s;
        if (p == NULL)
            retval = FAIL;
        else
            retval = ins_typebuf(p, REMAP_YES, 0, TRUE, silent);
        if (esc)
            vim_free(p);
    }
    if (colon && retval == OK)
        retval = ins_typebuf((char_u *)":", REMAP_YES, 0, TRUE, silent);
    return retval;
}

/*
 * Insert a yank register: copy it into the Read buffer.
 * Used by CTRL-R command and middle mouse button in insert mode.
 *
 * return FAIL for failure, OK otherwise
 */
    int
insert_reg(regname, literally)
    int         regname;
    int         literally;      /* insert literally, not as if typed */
{
    long        i;
    int         retval = OK;
    char_u      *arg;
    int         allocated;

    /*
     * It is possible to get into an endless loop by having CTRL-R a in
     * register a and then, in insert mode, doing CTRL-R a.
     * If you hit CTRL-C, the loop will be broken here.
     */
    ui_breakcheck();
    if (got_int)
        return FAIL;

    /* check for valid regname */
    if (regname != NUL && !valid_yank_reg(regname, FALSE))
        return FAIL;

#ifdef FEAT_CLIPBOARD
    regname = may_get_selection(regname);
#endif

    if (regname == '.')                 /* insert last inserted text */
        retval = stuff_inserted(NUL, 1L, TRUE);
    else if (get_spec_reg(regname, &arg, &allocated, TRUE))
    {
        if (arg == NULL)
            return FAIL;
        stuffescaped(arg, literally);
        if (allocated)
            vim_free(arg);
    }
    else                                /* name or number register */
    {
        get_yank_register(regname, FALSE);
        if (y_current->y_array == NULL)
            retval = FAIL;
        else
        {
            for (i = 0; i < y_current->y_size; ++i)
            {
                stuffescaped(y_current->y_array[i], literally);
                /*
                 * Insert a newline between lines and after last line if
                 * y_type is MLINE.
                 */
                if (y_current->y_type == MLINE || i < y_current->y_size - 1)
                    stuffcharReadbuff('\n');
            }
        }
    }

    return retval;
}

/*
 * Stuff a string into the typeahead buffer, such that edit() will insert it
 * literally ("literally" TRUE) or interpret is as typed characters.
 */
    static void
stuffescaped(arg, literally)
    char_u      *arg;
    int         literally;
{
    int         c;
    char_u      *start;

    while (*arg != NUL)
    {
        /* Stuff a sequence of normal ASCII characters, that's fast.  Also
         * stuff K_SPECIAL to get the effect of a special key when "literally"
         * is TRUE. */
        start = arg;
        while ((*arg >= ' '
#ifndef EBCDIC
                    && *arg < DEL /* EBCDIC: chars above space are normal */
#endif
                    )
                || (*arg == K_SPECIAL && !literally))
            ++arg;
        if (arg > start)
            stuffReadbuffLen(start, (long)(arg - start));

        /* stuff a single special character */
        if (*arg != NUL)
        {
#ifdef FEAT_MBYTE
            if (has_mbyte)
                c = mb_ptr2char_adv(&arg);
            else
#endif
                c = *arg++;
            if (literally && ((c < ' ' && c != TAB) || c == DEL))
                stuffcharReadbuff(Ctrl_V);
            stuffcharReadbuff(c);
        }
    }
}

/*
 * If "regname" is a special register, return TRUE and store a pointer to its
 * value in "argp".
 */
    int
get_spec_reg(regname, argp, allocated, errmsg)
    int         regname;
    char_u      **argp;
    int         *allocated;     /* return: TRUE when value was allocated */
    int         errmsg;         /* give error message when failing */
{
    int         cnt;

    *argp = NULL;
    *allocated = FALSE;
    switch (regname)
    {
        case '%':               /* file name */
            if (errmsg)
                check_fname();  /* will give emsg if not set */
            *argp = curbuf->b_fname;
            return TRUE;

        case '#':               /* alternate file name */
            *argp = getaltfname(errmsg);        /* may give emsg if not set */
            return TRUE;

#ifdef FEAT_EVAL
        case '=':               /* result of expression */
            *argp = get_expr_line();
            *allocated = TRUE;
            return TRUE;
#endif

        case ':':               /* last command line */
            if (last_cmdline == NULL && errmsg)
                EMSG(_(e_nolastcmd));
            *argp = last_cmdline;
            return TRUE;

        case '/':               /* last search-pattern */
            if (last_search_pat() == NULL && errmsg)
                EMSG(_(e_noprevre));
            *argp = last_search_pat();
            return TRUE;

        case '.':               /* last inserted text */
            *argp = get_last_insert_save();
            *allocated = TRUE;
            if (*argp == NULL && errmsg)
                EMSG(_(e_noinstext));
            return TRUE;

#ifdef FEAT_SEARCHPATH
        case Ctrl_F:            /* Filename under cursor */
        case Ctrl_P:            /* Path under cursor, expand via "path" */
            if (!errmsg)
                return FALSE;
            *argp = file_name_at_cursor(FNAME_MESS | FNAME_HYP
                            | (regname == Ctrl_P ? FNAME_EXP : 0), 1L, NULL);
            *allocated = TRUE;
            return TRUE;
#endif

        case Ctrl_W:            /* word under cursor */
        case Ctrl_A:            /* WORD (mnemonic All) under cursor */
            if (!errmsg)
                return FALSE;
            cnt = find_ident_under_cursor(argp, regname == Ctrl_W
                                   ?  (FIND_IDENT|FIND_STRING) : FIND_STRING);
            *argp = cnt ? vim_strnsave(*argp, cnt) : NULL;
            *allocated = TRUE;
            return TRUE;

        case '_':               /* black hole: always empty */
            *argp = (char_u *)"";
            return TRUE;
    }

    return FALSE;
}

/*
 * Paste a yank register into the command line.
 * Only for non-special registers.
 * Used by CTRL-R command in command-line mode
 * insert_reg() can't be used here, because special characters from the
 * register contents will be interpreted as commands.
 *
 * return FAIL for failure, OK otherwise
 */
    int
cmdline_paste_reg(regname, literally, remcr)
    int regname;
    int literally;      /* Insert text literally instead of "as typed" */
    int remcr;          /* don't add trailing CR */
{
    long        i;

    get_yank_register(regname, FALSE);
    if (y_current->y_array == NULL)
        return FAIL;

    for (i = 0; i < y_current->y_size; ++i)
    {
        cmdline_paste_str(y_current->y_array[i], literally);

        /* Insert ^M between lines and after last line if type is MLINE.
         * Don't do this when "remcr" is TRUE and the next line is empty. */
        if (y_current->y_type == MLINE
                || (i < y_current->y_size - 1
                    && !(remcr
                        && i == y_current->y_size - 2
                        && *y_current->y_array[i + 1] == NUL)))
            cmdline_paste_str((char_u *)"\r", literally);

        /* Check for CTRL-C, in case someone tries to paste a few thousand
         * lines and gets bored. */
        ui_breakcheck();
        if (got_int)
            return FAIL;
    }
    return OK;
}

#if defined(FEAT_CLIPBOARD) || defined(PROTO)
/*
 * Adjust the register name pointed to with "rp" for the clipboard being
 * used always and the clipboard being available.
 */
    void
adjust_clip_reg(rp)
    int         *rp;
{
    /* If no reg. specified, and "unnamed" is in 'clipboard', use '*' reg. */
    if (*rp == 0 && clip_unnamed)
        *rp = '*';
    if (!clip_star.available && *rp == '*')
        *rp = 0;
    if (!clip_plus.available && *rp == '+')
        *rp = 0;
}
#endif

/*
 * op_delete - handle a delete operation
 *
 * return FAIL if undo failed, OK otherwise.
 */
    int
op_delete(oap)
    oparg_T   *oap;
{
    int                 n;
    linenr_T            lnum;
    char_u              *ptr;
#ifdef FEAT_VISUAL
    char_u              *newp, *oldp;
    struct block_def    bd;
#endif
    linenr_T            old_lcount = curbuf->b_ml.ml_line_count;
    int                 did_yank = FALSE;

    if (curbuf->b_ml.ml_flags & ML_EMPTY)           /* nothing to do */
        return OK;

    /* Nothing to delete, return here.  Do prepare undo, for op_change(). */
    if (oap->empty)
        return u_save_cursor();

    if (!curbuf->b_p_ma)
    {
        EMSG(_(e_modifiable));
        return FAIL;
    }

#ifdef FEAT_CLIPBOARD
    adjust_clip_reg(&oap->regname);
#endif

#ifdef FEAT_MBYTE
    if (has_mbyte)
        mb_adjust_opend(oap);
#endif

/*
 * Imitate the strange Vi behaviour: If the delete spans more than one line
 * and motion_type == MCHAR and the result is a blank line, make the delete
 * linewise.  Don't do this for the change command or Visual mode.
 */
    if (       oap->motion_type == MCHAR
#ifdef FEAT_VISUAL
            && !oap->is_VIsual
            && !oap->block_mode
#endif
            && oap->line_count > 1
            && oap->op_type == OP_DELETE)
    {
        ptr = ml_get(oap->end.lnum) + oap->end.col + oap->inclusive;
        ptr = skipwhite(ptr);
        if (*ptr == NUL && inindent(0))
            oap->motion_type = MLINE;
    }

/*
 * Check for trying to delete (e.g. "D") in an empty line.
 * Note: For the change operator it is ok.
 */
    if (       oap->motion_type == MCHAR
            && oap->line_count == 1
            && oap->op_type == OP_DELETE
            && *ml_get(oap->start.lnum) == NUL)
    {
        /*
         * It's an error to operate on an empty region, when 'E' included in
         * 'cpoptions' (Vi compatible).
         */
#ifdef FEAT_VIRTUALEDIT
        if (virtual_op)
            /* Virtual editing: Nothing gets deleted, but we set the '[ and ']
             * marks as if it happened. */
            goto setmarks;
#endif
        if (vim_strchr(p_cpo, CPO_EMPTYREGION) != NULL)
            beep_flush();
        return OK;
    }

/*
 * Do a yank of whatever we're about to delete.
 * If a yank register was specified, put the deleted text into that register.
 * For the black hole register '_' don't yank anything.
 */
    if (oap->regname != '_')
    {
        if (oap->regname != 0)
        {
            /* check for read-only register */
            if (!valid_yank_reg(oap->regname, TRUE))
            {
                beep_flush();
                return OK;
            }
            get_yank_register(oap->regname, TRUE); /* yank into specif'd reg. */
            if (op_yank(oap, TRUE, FALSE) == OK)   /* yank without message */
                did_yank = TRUE;
        }

        /*
         * Put deleted text into register 1 and shift number registers if the
         * delete contains a line break, or when a regname has been specified.
         */
        if (oap->regname != 0 || oap->motion_type == MLINE
                                   || oap->line_count > 1 || oap->use_reg_one)
        {
            y_current = &y_regs[9];
            free_yank_all();                    /* free register nine */
            for (n = 9; n > 1; --n)
                y_regs[n] = y_regs[n - 1];
            y_previous = y_current = &y_regs[1];
            y_regs[1].y_array = NULL;           /* set register one to empty */
            if (op_yank(oap, TRUE, FALSE) == OK)
                did_yank = TRUE;
        }

        /* Yank into small delete register when no register specified and the
         * delete is within one line. */
        if (oap->regname == 0 && oap->motion_type != MLINE
                                                      && oap->line_count == 1)
        {
            oap->regname = '-';
            get_yank_register(oap->regname, TRUE);
            if (op_yank(oap, TRUE, FALSE) == OK)
                did_yank = TRUE;
            oap->regname = 0;
        }

        /*
         * If there's too much stuff to fit in the yank register, then get a
         * confirmation before doing the delete. This is crude, but simple.
         * And it avoids doing a delete of something we can't put back if we
         * want.
         */
        if (!did_yank)
        {
            int msg_silent_save = msg_silent;

            msg_silent = 0;     /* must display the prompt */
            n = ask_yesno((char_u *)_("cannot yank; delete anyway"), TRUE);
            msg_silent = msg_silent_save;
            if (n != 'y')
            {
                EMSG(_(e_abort));
                return FAIL;
            }
        }
    }

#ifdef FEAT_VISUAL
/*
 * block mode delete
 */
    if (oap->block_mode)
    {
        if (u_save((linenr_T)(oap->start.lnum - 1),
                               (linenr_T)(oap->end.lnum + 1)) == FAIL)
            return FAIL;

        for (lnum = curwin->w_cursor.lnum; lnum <= oap->end.lnum; ++lnum)
        {
            block_prep(oap, &bd, lnum, TRUE);
            if (bd.textlen == 0)        /* nothing to delete */
                continue;

            /* Adjust cursor position for tab replaced by spaces and 'lbr'. */
            if (lnum == curwin->w_cursor.lnum)
            {
                curwin->w_cursor.col = bd.textcol + bd.startspaces;
# ifdef FEAT_VIRTUALEDIT
                curwin->w_cursor.coladd = 0;
# endif
            }

            /* n == number of chars deleted
             * If we delete a TAB, it may be replaced by several characters.
             * Thus the number of characters may increase!
             */
            n = bd.textlen - bd.startspaces - bd.endspaces;
            oldp = ml_get(lnum);
            newp = alloc_check((unsigned)STRLEN(oldp) + 1 - n);
            if (newp == NULL)
                continue;
            /* copy up to deleted part */
            mch_memmove(newp, oldp, (size_t)bd.textcol);
            /* insert spaces */
            copy_spaces(newp + bd.textcol,
                                     (size_t)(bd.startspaces + bd.endspaces));
            /* copy the part after the deleted part */
            oldp += bd.textcol + bd.textlen;
            STRMOVE(newp + bd.textcol + bd.startspaces + bd.endspaces, oldp);
            /* replace the line */
            ml_replace(lnum, newp, FALSE);
        }

        check_cursor_col();
        changed_lines(curwin->w_cursor.lnum, curwin->w_cursor.col,
                                                       oap->end.lnum + 1, 0L);
        oap->line_count = 0;        /* no lines deleted */
    }
    else
#endif
        if (oap->motion_type == MLINE)
    {
        if (oap->op_type == OP_CHANGE)
        {
            /* Delete the lines except the first one.  Temporarily move the
             * cursor to the next line.  Save the current line number, if the
             * last line is deleted it may be changed.
             */
            if (oap->line_count > 1)
            {
                lnum = curwin->w_cursor.lnum;
                ++curwin->w_cursor.lnum;
                del_lines((long)(oap->line_count - 1), TRUE);
                curwin->w_cursor.lnum = lnum;
            }
            if (u_save_cursor() == FAIL)
                return FAIL;
            if (curbuf->b_p_ai)             /* don't delete indent */
            {
                beginline(BL_WHITE);        /* cursor on first non-white */
                did_ai = TRUE;              /* delete the indent when ESC hit */
                ai_col = curwin->w_cursor.col;
            }
            else
                beginline(0);               /* cursor in column 0 */
            truncate_line(FALSE);   /* delete the rest of the line */
                                    /* leave cursor past last char in line */
            if (oap->line_count > 1)
                u_clearline();      /* "U" command not possible after "2cc" */
        }
        else
        {
            del_lines(oap->line_count, TRUE);
            beginline(BL_WHITE | BL_FIX);
            u_clearline();      /* "U" command not possible after "dd" */
        }
    }
    else
    {
#ifdef FEAT_VIRTUALEDIT
        if (virtual_op)
        {
            int         endcol = 0;

            /* For virtualedit: break the tabs that are partly included. */
            if (gchar_pos(&oap->start) == '\t')
            {
                if (u_save_cursor() == FAIL)    /* save first line for undo */
                    return FAIL;
                if (oap->line_count == 1)
                    endcol = getviscol2(oap->end.col, oap->end.coladd);
                coladvance_force(getviscol2(oap->start.col, oap->start.coladd));
                oap->start = curwin->w_cursor;
                if (oap->line_count == 1)
                {
                    coladvance(endcol);
                    oap->end.col = curwin->w_cursor.col;
                    oap->end.coladd = curwin->w_cursor.coladd;
                    curwin->w_cursor = oap->start;
                }
            }

            /* Break a tab only when it's included in the area. */
            if (gchar_pos(&oap->end) == '\t'
                                     && (int)oap->end.coladd < oap->inclusive)
            {
                /* save last line for undo */
                if (u_save((linenr_T)(oap->end.lnum - 1),
                                       (linenr_T)(oap->end.lnum + 1)) == FAIL)
                    return FAIL;
                curwin->w_cursor = oap->end;
                coladvance_force(getviscol2(oap->end.col, oap->end.coladd));
                oap->end = curwin->w_cursor;
                curwin->w_cursor = oap->start;
            }
        }
#endif

        if (oap->line_count == 1)       /* delete characters within one line */
        {
            if (u_save_cursor() == FAIL)        /* save line for undo */
                return FAIL;

            /* if 'cpoptions' contains '$', display '$' at end of change */
            if (           vim_strchr(p_cpo, CPO_DOLLAR) != NULL
                    && oap->op_type == OP_CHANGE
                    && oap->end.lnum == curwin->w_cursor.lnum
#ifdef FEAT_VISUAL
                    && !oap->is_VIsual
#endif
                    )
                display_dollar(oap->end.col - !oap->inclusive);

            n = oap->end.col - oap->start.col + 1 - !oap->inclusive;

#ifdef FEAT_VIRTUALEDIT
            if (virtual_op)
            {
                /* fix up things for virtualedit-delete:
                 * break the tabs which are going to get in our way
                 */
                char_u          *curline = ml_get_curline();
                int             len = (int)STRLEN(curline);

                if (oap->end.coladd != 0
                        && (int)oap->end.col >= len - 1
                        && !(oap->start.coladd && (int)oap->end.col >= len - 1))
                    n++;
                /* Delete at least one char (e.g, when on a control char). */
                if (n == 0 && oap->start.coladd != oap->end.coladd)
                    n = 1;

                /* When deleted a char in the line, reset coladd. */
                if (gchar_cursor() != NUL)
                    curwin->w_cursor.coladd = 0;
            }
#endif
            (void)del_bytes((long)n, !virtual_op, oap->op_type == OP_DELETE
#ifdef FEAT_VISUAL
                                    && !oap->is_VIsual
#endif
                                                        );
        }
        else                            /* delete characters between lines */
        {
            pos_T   curpos;

            /* save deleted and changed lines for undo */
            if (u_save((linenr_T)(curwin->w_cursor.lnum - 1),
                 (linenr_T)(curwin->w_cursor.lnum + oap->line_count)) == FAIL)
                return FAIL;

            truncate_line(TRUE);        /* delete from cursor to end of line */

            curpos = curwin->w_cursor;  /* remember curwin->w_cursor */
            ++curwin->w_cursor.lnum;
            del_lines((long)(oap->line_count - 2), FALSE);

            /* delete from start of line until op_end */
            curwin->w_cursor.col = 0;
            (void)del_bytes((long)(oap->end.col + 1 - !oap->inclusive),
                                        !virtual_op, oap->op_type == OP_DELETE
#ifdef FEAT_VISUAL
                                        && !oap->is_VIsual
#endif
                                                            );
            curwin->w_cursor = curpos;          /* restore curwin->w_cursor */

            (void)do_join(FALSE);
        }
    }

    msgmore(curbuf->b_ml.ml_line_count - old_lcount);

#ifdef FEAT_VIRTUALEDIT
setmarks:
#endif
#ifdef FEAT_VISUAL
    if (oap->block_mode)
    {
        curbuf->b_op_end.lnum = oap->end.lnum;
        curbuf->b_op_end.col = oap->start.col;
    }
    else
#endif
        curbuf->b_op_end = oap->start;
    curbuf->b_op_start = oap->start;

    return OK;
}

#ifdef FEAT_MBYTE
/*
 * Adjust end of operating area for ending on a multi-byte character.
 * Used for deletion.
 */
    static void
mb_adjust_opend(oap)
    oparg_T     *oap;
{
    char_u      *p;

    if (oap->inclusive)
    {
        p = ml_get(oap->end.lnum);
        oap->end.col += mb_tail_off(p, p + oap->end.col);
    }
}
#endif

#if defined(FEAT_VISUALEXTRA) || defined(PROTO)
/*
 * Replace a whole area with one character.
 */
    int
op_replace(oap, c)
    oparg_T   *oap;
    int         c;
{
    int                 n, numc;
#ifdef FEAT_MBYTE
    int                 num_chars;
#endif
    char_u              *newp, *oldp;
    size_t              oldlen;
    struct block_def    bd;

    if ((curbuf->b_ml.ml_flags & ML_EMPTY ) || oap->empty)
        return OK;          /* nothing to do */

#ifdef FEAT_MBYTE
    if (has_mbyte)
        mb_adjust_opend(oap);
#endif

    if (u_save((linenr_T)(oap->start.lnum - 1),
                                       (linenr_T)(oap->end.lnum + 1)) == FAIL)
        return FAIL;

    /*
     * block mode replace
     */
    if (oap->block_mode)
    {
        bd.is_MAX = (curwin->w_curswant == MAXCOL);
        for ( ; curwin->w_cursor.lnum <= oap->end.lnum; ++curwin->w_cursor.lnum)
        {
            block_prep(oap, &bd, curwin->w_cursor.lnum, TRUE);
            if (bd.textlen == 0 && (!virtual_op || bd.is_MAX))
                continue;           /* nothing to replace */

            /* n == number of extra chars required
             * If we split a TAB, it may be replaced by several characters.
             * Thus the number of characters may increase!
             */
#ifdef FEAT_VIRTUALEDIT
            /* If the range starts in virtual space, count the initial
             * coladd offset as part of "startspaces" */
            if (virtual_op && bd.is_short && *bd.textstart == NUL)
            {
                pos_T vpos;

                getvpos(&vpos, oap->start_vcol);
                bd.startspaces += vpos.coladd;
                n = bd.startspaces;
            }
            else
#endif
                /* allow for pre spaces */
                n = (bd.startspaces ? bd.start_char_vcols - 1 : 0);

            /* allow for post spp */
            n += (bd.endspaces
#ifdef FEAT_VIRTUALEDIT
                    && !bd.is_oneChar
#endif
                    && bd.end_char_vcols > 0) ? bd.end_char_vcols - 1 : 0;
            /* Figure out how many characters to replace. */
            numc = oap->end_vcol - oap->start_vcol + 1;
            if (bd.is_short && (!virtual_op || bd.is_MAX))
                numc -= (oap->end_vcol - bd.end_vcol) + 1;

#ifdef FEAT_MBYTE
            /* A double-wide character can be replaced only up to half the
             * times. */
            if ((*mb_char2cells)(c) > 1)
            {
                if ((numc & 1) && !bd.is_short)
                {
                    ++bd.endspaces;
                    ++n;
                }
                numc = numc / 2;
            }

            /* Compute bytes needed, move character count to num_chars. */
            num_chars = numc;
            numc *= (*mb_char2len)(c);
#endif
            /* oldlen includes textlen, so don't double count */
            n += numc - bd.textlen;

            oldp = ml_get_curline();
            oldlen = STRLEN(oldp);
            newp = alloc_check((unsigned)oldlen + 1 + n);
            if (newp == NULL)
                continue;
            vim_memset(newp, NUL, (size_t)(oldlen + 1 + n));
            /* copy up to deleted part */
            mch_memmove(newp, oldp, (size_t)bd.textcol);
            oldp += bd.textcol + bd.textlen;
            /* insert pre-spaces */
            copy_spaces(newp + bd.textcol, (size_t)bd.startspaces);
            /* insert replacement chars CHECK FOR ALLOCATED SPACE */
#ifdef FEAT_MBYTE
            if (has_mbyte)
            {
                n = (int)STRLEN(newp);
                while (--num_chars >= 0)
                    n += (*mb_char2bytes)(c, newp + n);
            }
            else
#endif
                copy_chars(newp + STRLEN(newp), (size_t)numc, c);
            if (!bd.is_short)
            {
                /* insert post-spaces */
                copy_spaces(newp + STRLEN(newp), (size_t)bd.endspaces);
                /* copy the part after the changed part */
                STRMOVE(newp + STRLEN(newp), oldp);
            }
            /* replace the line */
            ml_replace(curwin->w_cursor.lnum, newp, FALSE);
        }
    }
    else
    {
        /*
         * MCHAR and MLINE motion replace.
         */
        if (oap->motion_type == MLINE)
        {
            oap->start.col = 0;
            curwin->w_cursor.col = 0;
            oap->end.col = (colnr_T)STRLEN(ml_get(oap->end.lnum));
            if (oap->end.col)
                --oap->end.col;
        }
        else if (!oap->inclusive)
            dec(&(oap->end));

        while (ltoreq(curwin->w_cursor, oap->end))
        {
            n = gchar_cursor();
            if (n != NUL)
            {
#ifdef FEAT_MBYTE
                if ((*mb_char2len)(c) > 1 || (*mb_char2len)(n) > 1)
                {
                    /* This is slow, but it handles replacing a single-byte
                     * with a multi-byte and the other way around. */
                    oap->end.col += (*mb_char2len)(c) - (*mb_char2len)(n);
                    n = State;
                    State = REPLACE;
                    ins_char(c);
                    State = n;
                    /* Backup to the replaced character. */
                    dec_cursor();
                }
                else
#endif
                {
#ifdef FEAT_VIRTUALEDIT
                    if (n == TAB)
                    {
                        int end_vcol = 0;

                        if (curwin->w_cursor.lnum == oap->end.lnum)
                        {
                            /* oap->end has to be recalculated when
                             * the tab breaks */
                            end_vcol = getviscol2(oap->end.col,
                                                             oap->end.coladd);
                        }
                        coladvance_force(getviscol());
                        if (curwin->w_cursor.lnum == oap->end.lnum)
                            getvpos(&oap->end, end_vcol);
                    }
#endif
                    pchar(curwin->w_cursor, c);
                }
            }
#ifdef FEAT_VIRTUALEDIT
            else if (virtual_op && curwin->w_cursor.lnum == oap->end.lnum)
            {
                int virtcols = oap->end.coladd;

                if (curwin->w_cursor.lnum == oap->start.lnum
                        && oap->start.col == oap->end.col && oap->start.coladd)
                    virtcols -= oap->start.coladd;

                /* oap->end has been trimmed so it's effectively inclusive;
                 * as a result an extra +1 must be counted so we don't
                 * trample the NUL byte. */
                coladvance_force(getviscol2(oap->end.col, oap->end.coladd) + 1);
                curwin->w_cursor.col -= (virtcols + 1);
                for (; virtcols >= 0; virtcols--)
                {
                    pchar(curwin->w_cursor, c);
                    if (inc(&curwin->w_cursor) == -1)
                        break;
                }
            }
#endif

            /* Advance to next character, stop at the end of the file. */
            if (inc_cursor() == -1)
                break;
        }
    }

    curwin->w_cursor = oap->start;
    check_cursor();
    changed_lines(oap->start.lnum, oap->start.col, oap->end.lnum + 1, 0L);

    /* Set "'[" and "']" marks. */
    curbuf->b_op_start = oap->start;
    curbuf->b_op_end = oap->end;

    return OK;
}
#endif

static int swapchars __ARGS((int op_type, pos_T *pos, int length));

/*
 * Handle the (non-standard vi) tilde operator.  Also for "gu", "gU" and "g?".
 */
    void
op_tilde(oap)
    oparg_T     *oap;
{
    pos_T               pos;
#ifdef FEAT_VISUAL
    struct block_def    bd;
#endif
    int                 did_change = FALSE;

    if (u_save((linenr_T)(oap->start.lnum - 1),
                                       (linenr_T)(oap->end.lnum + 1)) == FAIL)
        return;

    pos = oap->start;
#ifdef FEAT_VISUAL
    if (oap->block_mode)                    /* Visual block mode */
    {
        for (; pos.lnum <= oap->end.lnum; ++pos.lnum)
        {
            int one_change;

            block_prep(oap, &bd, pos.lnum, FALSE);
            pos.col = bd.textcol;
            one_change = swapchars(oap->op_type, &pos, bd.textlen);
            did_change |= one_change;

# ifdef FEAT_NETBEANS_INTG
            if (usingNetbeans && one_change)
            {
                char_u *ptr = ml_get_buf(curbuf, pos.lnum, FALSE);

                netbeans_removed(curbuf, pos.lnum, bd.textcol,
                                                            (long)bd.textlen);
                netbeans_inserted(curbuf, pos.lnum, bd.textcol,
                                    &ptr[bd.textcol], bd.textlen);
            }
# endif
        }
        if (did_change)
            changed_lines(oap->start.lnum, 0, oap->end.lnum + 1, 0L);
    }
    else                                    /* not block mode */
#endif
    {
        if (oap->motion_type == MLINE)
        {
            oap->start.col = 0;
            pos.col = 0;
            oap->end.col = (colnr_T)STRLEN(ml_get(oap->end.lnum));
            if (oap->end.col)
                --oap->end.col;
        }
        else if (!oap->inclusive)
            dec(&(oap->end));

        if (pos.lnum == oap->end.lnum)
            did_change = swapchars(oap->op_type, &pos,
                                                  oap->end.col - pos.col + 1);
        else
            for (;;)
            {
                did_change |= swapchars(oap->op_type, &pos,
                                pos.lnum == oap->end.lnum ? oap->end.col + 1:
                                           (int)STRLEN(ml_get_pos(&pos)));
                if (ltoreq(oap->end, pos) || inc(&pos) == -1)
                    break;
            }
        if (did_change)
        {
            changed_lines(oap->start.lnum, oap->start.col, oap->end.lnum + 1,
                                                                          0L);
#ifdef FEAT_NETBEANS_INTG
            if (usingNetbeans && did_change)
            {
                char_u *ptr;
                int count;

                pos = oap->start;
                while (pos.lnum < oap->end.lnum)
                {
                    ptr = ml_get_buf(curbuf, pos.lnum, FALSE);
                    count = (int)STRLEN(ptr) - pos.col;
                    netbeans_removed(curbuf, pos.lnum, pos.col, (long)count);
                    netbeans_inserted(curbuf, pos.lnum, pos.col,
                                                 &ptr[pos.col], count);
                    pos.col = 0;
                    pos.lnum++;
                }
                ptr = ml_get_buf(curbuf, pos.lnum, FALSE);
                count = oap->end.col - pos.col + 1;
                netbeans_removed(curbuf, pos.lnum, pos.col, (long)count);
                netbeans_inserted(curbuf, pos.lnum, pos.col,
                                                 &ptr[pos.col], count);
            }
#endif
        }
    }

#ifdef FEAT_VISUAL
    if (!did_change && oap->is_VIsual)
        /* No change: need to remove the Visual selection */
        redraw_curbuf_later(INVERTED);
#endif

    /*
     * Set '[ and '] marks.
     */
    curbuf->b_op_start = oap->start;
    curbuf->b_op_end = oap->end;

    if (oap->line_count > p_report)
    {
        if (oap->line_count == 1)
            MSG(_("1 line changed"));
        else
            smsg((char_u *)_("%ld lines changed"), oap->line_count);
    }
}

/*
 * Invoke swapchar() on "length" bytes at position "pos".
 * "pos" is advanced to just after the changed characters.
 * "length" is rounded up to include the whole last multi-byte character.
 * Also works correctly when the number of bytes changes.
 * Returns TRUE if some character was changed.
 */
    static int
swapchars(op_type, pos, length)
    int         op_type;
    pos_T       *pos;
    int         length;
{
    int todo;
    int did_change = 0;

    for (todo = length; todo > 0; --todo)
    {
# ifdef FEAT_MBYTE
        if (has_mbyte)
            /* we're counting bytes, not characters */
            todo -= (*mb_ptr2len)(ml_get_pos(pos)) - 1;
# endif
        did_change |= swapchar(op_type, pos);
        if (inc(pos) == -1)    /* at end of file */
            break;
    }
    return did_change;
}

/*
 * If op_type == OP_UPPER: make uppercase,
 * if op_type == OP_LOWER: make lowercase,
 * if op_type == OP_ROT13: do rot13 encoding,
 * else swap case of character at 'pos'
 * returns TRUE when something actually changed.
 */
    int
swapchar(op_type, pos)
    int     op_type;
    pos_T    *pos;
{
    int     c;
    int     nc;

    c = gchar_pos(pos);

    /* Only do rot13 encoding for ASCII characters. */
    if (c >= 0x80 && op_type == OP_ROT13)
        return FALSE;

#ifdef FEAT_MBYTE
    if (op_type == OP_UPPER && c == 0xdf
                      && (enc_latin1like || STRCMP(p_enc, "iso-8859-2") == 0))
    {
        pos_T   sp = curwin->w_cursor;

        /* Special handling of German sharp s: change to "SS". */
        curwin->w_cursor = *pos;
        del_char(FALSE);
        ins_char('S');
        ins_char('S');
        curwin->w_cursor = sp;
        inc(pos);
    }

    if (enc_dbcs != 0 && c >= 0x100)    /* No lower/uppercase letter */
        return FALSE;
#endif
    nc = c;
    if (MB_ISLOWER(c))
    {
        if (op_type == OP_ROT13)
            nc = ROT13(c, 'a');
        else if (op_type != OP_LOWER)
            nc = MB_TOUPPER(c);
    }
    else if (MB_ISUPPER(c))
    {
        if (op_type == OP_ROT13)
            nc = ROT13(c, 'A');
        else if (op_type != OP_UPPER)
            nc = MB_TOLOWER(c);
    }
    if (nc != c)
    {
#ifdef FEAT_MBYTE
        if (enc_utf8 && (c >= 0x80 || nc >= 0x80))
        {
            pos_T   sp = curwin->w_cursor;

            curwin->w_cursor = *pos;
            del_char(FALSE);
            ins_char(nc);
            curwin->w_cursor = sp;
        }
        else
#endif
            pchar(*pos, nc);
        return TRUE;
    }
    return FALSE;
}

#if defined(FEAT_VISUALEXTRA) || defined(PROTO)
/*
 * op_insert - Insert and append operators for Visual mode.
 */
    void
op_insert(oap, count1)
    oparg_T     *oap;
    long        count1;
{
    long                ins_len, pre_textlen = 0;
    char_u              *firstline, *ins_text;
    struct block_def    bd;
    int                 i;

    /* edit() changes this - record it for OP_APPEND */
    bd.is_MAX = (curwin->w_curswant == MAXCOL);

    /* vis block is still marked. Get rid of it now. */
    curwin->w_cursor.lnum = oap->start.lnum;
    update_screen(INVERTED);

    if (oap->block_mode)
    {
#ifdef FEAT_VIRTUALEDIT
        /* When 'virtualedit' is used, need to insert the extra spaces before
         * doing block_prep().  When only "block" is used, virtual edit is
         * already disabled, but still need it when calling
         * coladvance_force(). */
        if (curwin->w_cursor.coladd > 0)
        {
            int         old_ve_flags = ve_flags;

            ve_flags = VE_ALL;
            if (u_save_cursor() == FAIL)
                return;
            coladvance_force(oap->op_type == OP_APPEND
                                           ? oap->end_vcol + 1 : getviscol());
            if (oap->op_type == OP_APPEND)
                --curwin->w_cursor.col;
            ve_flags = old_ve_flags;
        }
#endif
        /* Get the info about the block before entering the text */
        block_prep(oap, &bd, oap->start.lnum, TRUE);
        firstline = ml_get(oap->start.lnum) + bd.textcol;
        if (oap->op_type == OP_APPEND)
            firstline += bd.textlen;
        pre_textlen = (long)STRLEN(firstline);
    }

    if (oap->op_type == OP_APPEND)
    {
        if (oap->block_mode
#ifdef FEAT_VIRTUALEDIT
                && curwin->w_cursor.coladd == 0
#endif
           )
        {
            /* Move the cursor to the character right of the block. */
            curwin->w_set_curswant = TRUE;
            while (*ml_get_cursor() != NUL
                    && (curwin->w_cursor.col < bd.textcol + bd.textlen))
                ++curwin->w_cursor.col;
            if (bd.is_short && !bd.is_MAX)
            {
                /* First line was too short, make it longer and adjust the
                 * values in "bd". */
                if (u_save_cursor() == FAIL)
                    return;
                for (i = 0; i < bd.endspaces; ++i)
                    ins_char(' ');
                bd.textlen += bd.endspaces;
            }
        }
        else
        {
            curwin->w_cursor = oap->end;
            check_cursor_col();

            /* Works just like an 'i'nsert on the next character. */
            if (!lineempty(curwin->w_cursor.lnum)
                    && oap->start_vcol != oap->end_vcol)
                inc_cursor();
        }
    }

    edit(NUL, FALSE, (linenr_T)count1);

    /* If user has moved off this line, we don't know what to do, so do
     * nothing.
     * Also don't repeat the insert when Insert mode ended with CTRL-C. */
    if (curwin->w_cursor.lnum != oap->start.lnum || got_int)
        return;

    if (oap->block_mode)
    {
        struct block_def        bd2;

        /*
         * Spaces and tabs in the indent may have changed to other spaces and
         * tabs.  Get the starting column again and correct the length.
         * Don't do this when "$" used, end-of-line will have changed.
         */
        block_prep(oap, &bd2, oap->start.lnum, TRUE);
        if (!bd.is_MAX || bd2.textlen < bd.textlen)
        {
            if (oap->op_type == OP_APPEND)
            {
                pre_textlen += bd2.textlen - bd.textlen;
                if (bd2.endspaces)
                    --bd2.textlen;
            }
            bd.textcol = bd2.textcol;
            bd.textlen = bd2.textlen;
        }

        /*
         * Subsequent calls to ml_get() flush the firstline data - take a
         * copy of the required string.
         */
        firstline = ml_get(oap->start.lnum) + bd.textcol;
        if (oap->op_type == OP_APPEND)
            firstline += bd.textlen;
        if ((ins_len = (long)STRLEN(firstline) - pre_textlen) > 0)
        {
            ins_text = vim_strnsave(firstline, (int)ins_len);
            if (ins_text != NULL)
            {
                /* block handled here */
                if (u_save(oap->start.lnum,
                                         (linenr_T)(oap->end.lnum + 1)) == OK)
                    block_insert(oap, ins_text, (oap->op_type == OP_INSERT),
                                                                         &bd);

                curwin->w_cursor.col = oap->start.col;
                check_cursor();
                vim_free(ins_text);
            }
        }
    }
}
#endif

/*
 * op_change - handle a change operation
 *
 * return TRUE if edit() returns because of a CTRL-O command
 */
    int
op_change(oap)
    oparg_T     *oap;
{
    colnr_T             l;
    int                 retval;
#ifdef FEAT_VISUALEXTRA
    long                offset;
    linenr_T            linenr;
    long                ins_len;
    long                pre_textlen = 0;
    long                pre_indent = 0;
    char_u              *firstline;
    char_u              *ins_text, *newp, *oldp;
    struct block_def    bd;
#endif

    l = oap->start.col;
    if (oap->motion_type == MLINE)
    {
        l = 0;
#ifdef FEAT_SMARTINDENT
        if (!p_paste && curbuf->b_p_si
# ifdef FEAT_CINDENT
                && !curbuf->b_p_cin
# endif
                )
            can_si = TRUE;      /* It's like opening a new line, do si */
#endif
    }

    /* First delete the text in the region.  In an empty buffer only need to
     * save for undo */
    if (curbuf->b_ml.ml_flags & ML_EMPTY)
    {
        if (u_save_cursor() == FAIL)
            return FALSE;
    }
    else if (op_delete(oap) == FAIL)
        return FALSE;

    if ((l > curwin->w_cursor.col) && !lineempty(curwin->w_cursor.lnum)
                                                         && !virtual_op)
        inc_cursor();

#ifdef FEAT_VISUALEXTRA
    /* check for still on same line (<CR> in inserted text meaningless) */
    /* skip blank lines too */
    if (oap->block_mode)
    {
# ifdef FEAT_VIRTUALEDIT
        /* Add spaces before getting the current line length. */
        if (virtual_op && (curwin->w_cursor.coladd > 0
                                                    || gchar_cursor() == NUL))
            coladvance_force(getviscol());
# endif
        firstline = ml_get(oap->start.lnum);
        pre_textlen = (long)STRLEN(firstline);
        pre_indent = (long)(skipwhite(firstline) - firstline);
        bd.textcol = curwin->w_cursor.col;
    }
#endif

#if defined(FEAT_LISP) || defined(FEAT_CINDENT)
    if (oap->motion_type == MLINE)
        fix_indent();
#endif

    retval = edit(NUL, FALSE, (linenr_T)1);

#ifdef FEAT_VISUALEXTRA
    /*
     * In Visual block mode, handle copying the new text to all lines of the
     * block.
     * Don't repeat the insert when Insert mode ended with CTRL-C.
     */
    if (oap->block_mode && oap->start.lnum != oap->end.lnum && !got_int)
    {
        /* Auto-indenting may have changed the indent.  If the cursor was past
         * the indent, exclude that indent change from the inserted text. */
        firstline = ml_get(oap->start.lnum);
        if (bd.textcol > (colnr_T)pre_indent)
        {
            long new_indent = (long)(skipwhite(firstline) - firstline);

            pre_textlen += new_indent - pre_indent;
            bd.textcol += new_indent - pre_indent;
        }

        ins_len = (long)STRLEN(firstline) - pre_textlen;
        if (ins_len > 0)
        {
            /* Subsequent calls to ml_get() flush the firstline data - take a
             * copy of the inserted text.  */
            if ((ins_text = alloc_check((unsigned)(ins_len + 1))) != NULL)
            {
                vim_strncpy(ins_text, firstline + bd.textcol, (size_t)ins_len);
                for (linenr = oap->start.lnum + 1; linenr <= oap->end.lnum;
                                                                     linenr++)
                {
                    block_prep(oap, &bd, linenr, TRUE);
                    if (!bd.is_short || virtual_op)
                    {
# ifdef FEAT_VIRTUALEDIT
                        pos_T vpos;

                        /* If the block starts in virtual space, count the
                         * initial coladd offset as part of "startspaces" */
                        if (bd.is_short)
                        {
                            linenr_T lnum = curwin->w_cursor.lnum;

                            curwin->w_cursor.lnum = linenr;
                            (void)getvpos(&vpos, oap->start_vcol);
                            curwin->w_cursor.lnum = lnum;
                        }
                        else
                            vpos.coladd = 0;
# endif
                        oldp = ml_get(linenr);
                        newp = alloc_check((unsigned)(STRLEN(oldp)
# ifdef FEAT_VIRTUALEDIT
                                                        + vpos.coladd
# endif
                                                              + ins_len + 1));
                        if (newp == NULL)
                            continue;
                        /* copy up to block start */
                        mch_memmove(newp, oldp, (size_t)bd.textcol);
                        offset = bd.textcol;
# ifdef FEAT_VIRTUALEDIT
                        copy_spaces(newp + offset, (size_t)vpos.coladd);
                        offset += vpos.coladd;
# endif
                        mch_memmove(newp + offset, ins_text, (size_t)ins_len);
                        offset += ins_len;
                        oldp += bd.textcol;
                        STRMOVE(newp + offset, oldp);
                        ml_replace(linenr, newp, FALSE);
                    }
                }
                check_cursor();

                changed_lines(oap->start.lnum + 1, 0, oap->end.lnum + 1, 0L);
            }
            vim_free(ins_text);
        }
    }
#endif

    return retval;
}

/*
 * set all the yank registers to empty (called from main())
 */
    void
init_yank()
{
    int         i;

    for (i = 0; i < NUM_REGISTERS; ++i)
        y_regs[i].y_array = NULL;
}

#if defined(EXITFREE) || defined(PROTO)
    void
clear_registers()
{
    int         i;

    for (i = 0; i < NUM_REGISTERS; ++i)
    {
        y_current = &y_regs[i];
        if (y_current->y_array != NULL)
            free_yank_all();
    }
}
#endif

/*
 * Free "n" lines from the current yank register.
 * Called for normal freeing and in case of error.
 */
    static void
free_yank(n)
    long        n;
{
    if (y_current->y_array != NULL)
    {
        long        i;

        for (i = n; --i >= 0; )
        {
#ifdef AMIGA        /* only for very slow machines */
            if ((i & 1023) == 1023)  /* this may take a while */
            {
                /*
                 * This message should never cause a hit-return message.
                 * Overwrite this message with any next message.
                 */
                ++no_wait_return;
                smsg((char_u *)_("freeing %ld lines"), i + 1);
                --no_wait_return;
                msg_didout = FALSE;
                msg_col = 0;
            }
#endif
            vim_free(y_current->y_array[i]);
        }
        vim_free(y_current->y_array);
        y_current->y_array = NULL;
#ifdef AMIGA
        if (n >= 1000)
            MSG("");
#endif
    }
}

    static void
free_yank_all()
{
    free_yank(y_current->y_size);
}

/*
 * Yank the text between "oap->start" and "oap->end" into a yank register.
 * If we are to append (uppercase register), we first yank into a new yank
 * register and then concatenate the old and the new one (so we keep the old
 * one in case of out-of-memory).
 *
 * return FAIL for failure, OK otherwise
 */
    int
op_yank(oap, deleting, mess)
    oparg_T   *oap;
    int     deleting;
    int     mess;
{
    long                y_idx;          /* index in y_array[] */
    struct yankreg      *curr;          /* copy of y_current */
    struct yankreg      newreg;         /* new yank register when appending */
    char_u              **new_ptr;
    linenr_T            lnum;           /* current line number */
    long                j;
    int                 yanktype = oap->motion_type;
    long                yanklines = oap->line_count;
    linenr_T            yankendlnum = oap->end.lnum;
    char_u              *p;
    char_u              *pnew;
    struct block_def    bd;

                                    /* check for read-only register */
    if (oap->regname != 0 && !valid_yank_reg(oap->regname, TRUE))
    {
        beep_flush();
        return FAIL;
    }
    if (oap->regname == '_')        /* black hole: nothing to do */
        return OK;

#ifdef FEAT_CLIPBOARD
    if (!clip_star.available && oap->regname == '*')
        oap->regname = 0;
    else if (!clip_plus.available && oap->regname == '+')
        oap->regname = 0;
#endif

    if (!deleting)                  /* op_delete() already set y_current */
        get_yank_register(oap->regname, TRUE);

    curr = y_current;
                                    /* append to existing contents */
    if (y_append && y_current->y_array != NULL)
        y_current = &newreg;
    else
        free_yank_all();            /* free previously yanked lines */

    /*
     * If the cursor was in column 1 before and after the movement, and the
     * operator is not inclusive, the yank is always linewise.
     */
    if (       oap->motion_type == MCHAR
            && oap->start.col == 0
            && !oap->inclusive
#ifdef FEAT_VISUAL
            && (!oap->is_VIsual || *p_sel == 'o')
            && !oap->block_mode
#endif
            && oap->end.col == 0
            && yanklines > 1)
    {
        yanktype = MLINE;
        --yankendlnum;
        --yanklines;
    }

    y_current->y_size = yanklines;
    y_current->y_type = yanktype;   /* set the yank register type */
#ifdef FEAT_VISUAL
    y_current->y_width = 0;
#endif
    y_current->y_array = (char_u **)lalloc_clear((long_u)(sizeof(char_u *) *
                                                            yanklines), TRUE);

    if (y_current->y_array == NULL)
    {
        y_current = curr;
        return FAIL;
    }

    y_idx = 0;
    lnum = oap->start.lnum;

#ifdef FEAT_VISUAL
    if (oap->block_mode)
    {
        /* Visual block mode */
        y_current->y_type = MBLOCK;         /* set the yank register type */
        y_current->y_width = oap->end_vcol - oap->start_vcol;

        if (curwin->w_curswant == MAXCOL && y_current->y_width > 0)
            y_current->y_width--;
    }
#endif

    for ( ; lnum <= yankendlnum; lnum++, y_idx++)
    {
        switch (y_current->y_type)
        {
#ifdef FEAT_VISUAL
            case MBLOCK:
                block_prep(oap, &bd, lnum, FALSE);
                if (yank_copy_line(&bd, y_idx) == FAIL)
                    goto fail;
                break;
#endif

            case MLINE:
                if ((y_current->y_array[y_idx] =
                            vim_strsave(ml_get(lnum))) == NULL)
                    goto fail;
                break;

            case MCHAR:
                {
                    colnr_T startcol = 0, endcol = MAXCOL;
#ifdef FEAT_VIRTUALEDIT
                    int is_oneChar = FALSE;
                    colnr_T cs, ce;
#endif
                    p = ml_get(lnum);
                    bd.startspaces = 0;
                    bd.endspaces = 0;

                    if (lnum == oap->start.lnum)
                    {
                        startcol = oap->start.col;
#ifdef FEAT_VIRTUALEDIT
                        if (virtual_op)
                        {
                            getvcol(curwin, &oap->start, &cs, NULL, &ce);
                            if (ce != cs && oap->start.coladd > 0)
                            {
                                /* Part of a tab selected -- but don't
                                 * double-count it. */
                                bd.startspaces = (ce - cs + 1)
                                                          - oap->start.coladd;
                                startcol++;
                            }
                        }
#endif
                    }

                    if (lnum == oap->end.lnum)
                    {
                        endcol = oap->end.col;
#ifdef FEAT_VIRTUALEDIT
                        if (virtual_op)
                        {
                            getvcol(curwin, &oap->end, &cs, NULL, &ce);
                            if (p[endcol] == NUL || (cs + oap->end.coladd < ce
# ifdef FEAT_MBYTE
                                        /* Don't add space for double-wide
                                         * char; endcol will be on last byte
                                         * of multi-byte char. */
                                        && (*mb_head_off)(p, p + endcol) == 0
# endif
                                        ))
                            {
                                if (oap->start.lnum == oap->end.lnum
                                            && oap->start.col == oap->end.col)
                                {
                                    /* Special case: inside a single char */
                                    is_oneChar = TRUE;
                                    bd.startspaces = oap->end.coladd
                                         - oap->start.coladd + oap->inclusive;
                                    endcol = startcol;
                                }
                                else
                                {
                                    bd.endspaces = oap->end.coladd
                                                             + oap->inclusive;
                                    endcol -= oap->inclusive;
                                }
                            }
                        }
#endif
                    }
                    if (startcol > endcol
#ifdef FEAT_VIRTUALEDIT
                            || is_oneChar
#endif
                            )
                        bd.textlen = 0;
                    else
                    {
                        if (endcol == MAXCOL)
                            endcol = (colnr_T)STRLEN(p);
                        bd.textlen = endcol - startcol + oap->inclusive;
                    }
                    bd.textstart = p + startcol;
                    if (yank_copy_line(&bd, y_idx) == FAIL)
                        goto fail;
                    break;
                }
                /* NOTREACHED */
        }
    }

    if (curr != y_current)      /* append the new block to the old block */
    {
        new_ptr = (char_u **)lalloc((long_u)(sizeof(char_u *) *
                                   (curr->y_size + y_current->y_size)), TRUE);
        if (new_ptr == NULL)
            goto fail;
        for (j = 0; j < curr->y_size; ++j)
            new_ptr[j] = curr->y_array[j];
        vim_free(curr->y_array);
        curr->y_array = new_ptr;

        if (yanktype == MLINE)  /* MLINE overrides MCHAR and MBLOCK */
            curr->y_type = MLINE;

        /* Concatenate the last line of the old block with the first line of
         * the new block, unless being Vi compatible. */
        if (curr->y_type == MCHAR && vim_strchr(p_cpo, CPO_REGAPPEND) == NULL)
        {
            pnew = lalloc((long_u)(STRLEN(curr->y_array[curr->y_size - 1])
                              + STRLEN(y_current->y_array[0]) + 1), TRUE);
            if (pnew == NULL)
            {
                y_idx = y_current->y_size - 1;
                goto fail;
            }
            STRCPY(pnew, curr->y_array[--j]);
            STRCAT(pnew, y_current->y_array[0]);
            vim_free(curr->y_array[j]);
            vim_free(y_current->y_array[0]);
            curr->y_array[j++] = pnew;
            y_idx = 1;
        }
        else
            y_idx = 0;
        while (y_idx < y_current->y_size)
            curr->y_array[j++] = y_current->y_array[y_idx++];
        curr->y_size = j;
        vim_free(y_current->y_array);
        y_current = curr;
    }
    if (mess)                   /* Display message about yank? */
    {
        if (yanktype == MCHAR
#ifdef FEAT_VISUAL
                && !oap->block_mode
#endif
                && yanklines == 1)
            yanklines = 0;
        /* Some versions of Vi use ">=" here, some don't...  */
        if (yanklines > p_report)
        {
            /* redisplay now, so message is not deleted */
            update_topline_redraw();
            if (yanklines == 1)
            {
#ifdef FEAT_VISUAL
                if (oap->block_mode)
                    MSG(_("block of 1 line yanked"));
                else
#endif
                    MSG(_("1 line yanked"));
            }
#ifdef FEAT_VISUAL
            else if (oap->block_mode)
                smsg((char_u *)_("block of %ld lines yanked"), yanklines);
#endif
            else
                smsg((char_u *)_("%ld lines yanked"), yanklines);
        }
    }

    /*
     * Set "'[" and "']" marks.
     */
    curbuf->b_op_start = oap->start;
    curbuf->b_op_end = oap->end;
    if (yanktype == MLINE
#ifdef FEAT_VISUAL
                && !oap->block_mode
#endif
       )
    {
        curbuf->b_op_start.col = 0;
        curbuf->b_op_end.col = MAXCOL;
    }

#ifdef FEAT_CLIPBOARD
    /*
     * If we were yanking to the '*' register, send result to clipboard.
     * If no register was specified, and "unnamed" in 'clipboard', make a copy
     * to the '*' register.
     */
    if (clip_star.available
            && (curr == &(y_regs[STAR_REGISTER])
                || (!deleting && oap->regname == 0 && clip_unnamed)))
    {
        if (curr != &(y_regs[STAR_REGISTER]))
            /* Copy the text from register 0 to the clipboard register. */
            copy_yank_reg(&(y_regs[STAR_REGISTER]));

        clip_own_selection(&clip_star);
        clip_gen_set_selection(&clip_star);
    }

# ifdef FEAT_X11
    /*
     * If we were yanking to the '+' register, send result to selection.
     * Also copy to the '*' register, in case auto-select is off.
     */
    else if (clip_plus.available && curr == &(y_regs[PLUS_REGISTER]))
    {
        /* No need to copy to * register upon 'unnamed' now - see below */
        clip_own_selection(&clip_plus);
        clip_gen_set_selection(&clip_plus);
        if (!clip_isautosel())
        {
            copy_yank_reg(&(y_regs[STAR_REGISTER]));
            clip_own_selection(&clip_star);
            clip_gen_set_selection(&clip_star);
        }
    }
# endif
#endif

    return OK;

fail:           /* free the allocated lines */
    free_yank(y_idx + 1);
    y_current = curr;
    return FAIL;
}

    static int
yank_copy_line(bd, y_idx)
    struct block_def    *bd;
    long                y_idx;
{
    char_u      *pnew;

    if ((pnew = alloc(bd->startspaces + bd->endspaces + bd->textlen + 1))
                                                                      == NULL)
        return FAIL;
    y_current->y_array[y_idx] = pnew;
    copy_spaces(pnew, (size_t)bd->startspaces);
    pnew += bd->startspaces;
    mch_memmove(pnew, bd->textstart, (size_t)bd->textlen);
    pnew += bd->textlen;
    copy_spaces(pnew, (size_t)bd->endspaces);
    pnew += bd->endspaces;
    *pnew = NUL;
    return OK;
}

#ifdef FEAT_CLIPBOARD
/*
 * Make a copy of the y_current register to register "reg".
 */
    static void
copy_yank_reg(reg)
    struct yankreg *reg;
{
    struct yankreg      *curr = y_current;
    long                j;

    y_current = reg;
    free_yank_all();
    *y_current = *curr;
    y_current->y_array = (char_u **)lalloc_clear(
                        (long_u)(sizeof(char_u *) * y_current->y_size), TRUE);
    if (y_current->y_array == NULL)
        y_current->y_size = 0;
    else
        for (j = 0; j < y_current->y_size; ++j)
            if ((y_current->y_array[j] = vim_strsave(curr->y_array[j])) == NULL)
            {
                free_yank(j);
                y_current->y_size = 0;
                break;
            }
    y_current = curr;
}
#endif

/*
 * Put contents of register "regname" into the text.
 * Caller must check "regname" to be valid!
 * "flags": PUT_FIXINDENT       make indent look nice
 *          PUT_CURSEND         leave cursor after end of new text
 *          PUT_LINE            force linewise put (":put")
 */
    void
do_put(regname, dir, count, flags)
    int         regname;
    int         dir;            /* BACKWARD for 'P', FORWARD for 'p' */
    long        count;
    int         flags;
{
    char_u      *ptr;
    char_u      *newp, *oldp;
    int         yanklen;
    int         totlen = 0;             /* init for gcc */
    linenr_T    lnum;
    colnr_T     col;
    long        i;                      /* index in y_array[] */
    int         y_type;
    long        y_size;
#ifdef FEAT_VISUAL
    int         oldlen;
    long        y_width = 0;
    colnr_T     vcol;
    int         delcount;
    int         incr = 0;
    long        j;
    struct block_def bd;
#endif
    char_u      **y_array = NULL;
    long        nr_lines = 0;
    pos_T       new_cursor;
    int         indent;
    int         orig_indent = 0;        /* init for gcc */
    int         indent_diff = 0;        /* init for gcc */
    int         first_indent = TRUE;
    int         lendiff = 0;
    pos_T       old_pos;
    char_u      *insert_string = NULL;
    int         allocated = FALSE;
    long        cnt;

#ifdef FEAT_CLIPBOARD
    /* Adjust register name for "unnamed" in 'clipboard'. */
    adjust_clip_reg(&regname);
    (void)may_get_selection(regname);
#endif

    if (flags & PUT_FIXINDENT)
        orig_indent = get_indent();

    curbuf->b_op_start = curwin->w_cursor;      /* default for '[ mark */
    curbuf->b_op_end = curwin->w_cursor;        /* default for '] mark */

    /*
     * Using inserted text works differently, because the register includes
     * special characters (newlines, etc.).
     */
    if (regname == '.')
    {
        (void)stuff_inserted((dir == FORWARD ? (count == -1 ? 'o' : 'a') :
                                    (count == -1 ? 'O' : 'i')), count, FALSE);
        /* Putting the text is done later, so can't really move the cursor to
         * the next character.  Use "l" to simulate it. */
        if ((flags & PUT_CURSEND) && gchar_cursor() != NUL)
            stuffcharReadbuff('l');
        return;
    }

    /*
     * For special registers '%' (file name), '#' (alternate file name) and
     * ':' (last command line), etc. we have to create a fake yank register.
     */
    if (get_spec_reg(regname, &insert_string, &allocated, TRUE))
    {
        if (insert_string == NULL)
            return;
    }

    if (insert_string != NULL)
    {
        y_type = MCHAR;
#ifdef FEAT_EVAL
        if (regname == '=')
        {
            /* For the = register we need to split the string at NL
             * characters. */
            /* Loop twice: count the number of lines and save them. */
            for (;;)
            {
                y_size = 0;
                ptr = insert_string;
                while (ptr != NULL)
                {
                    if (y_array != NULL)
                        y_array[y_size] = ptr;
                    ++y_size;
                    ptr = vim_strchr(ptr, '\n');
                    if (ptr != NULL)
                    {
                        if (y_array != NULL)
                            *ptr = NUL;
                        ++ptr;
                        /* A trailing '\n' makes the string linewise */
                        if (*ptr == NUL)
                        {
                            y_type = MLINE;
                            break;
                        }
                    }
                }
                if (y_array != NULL)
                    break;
                y_array = (char_u **)alloc((unsigned)
                                                 (y_size * sizeof(char_u *)));
                if (y_array == NULL)
                    goto end;
            }
        }
        else
#endif
        {
            y_size = 1;         /* use fake one-line yank register */
            y_array = &insert_string;
        }
    }
    else
    {
        get_yank_register(regname, FALSE);

        y_type = y_current->y_type;
#ifdef FEAT_VISUAL
        y_width = y_current->y_width;
#endif
        y_size = y_current->y_size;
        y_array = y_current->y_array;
    }

#ifdef FEAT_VISUAL
    if (y_type == MLINE)
    {
        if (flags & PUT_LINE_SPLIT)
        {
            /* "p" or "P" in Visual mode: split the lines to put the text in
             * between. */
            if (u_save_cursor() == FAIL)
                goto end;
            ptr = vim_strsave(ml_get_cursor());
            if (ptr == NULL)
                goto end;
            ml_append(curwin->w_cursor.lnum, ptr, (colnr_T)0, FALSE);
            vim_free(ptr);

            ptr = vim_strnsave(ml_get_curline(), curwin->w_cursor.col);
            if (ptr == NULL)
                goto end;
            ml_replace(curwin->w_cursor.lnum, ptr, FALSE);
            ++nr_lines;
            dir = FORWARD;
        }
        if (flags & PUT_LINE_FORWARD)
        {
            /* Must be "p" for a Visual block, put lines below the block. */
            curwin->w_cursor = curbuf->b_visual.vi_end;
            dir = FORWARD;
        }
        curbuf->b_op_start = curwin->w_cursor;  /* default for '[ mark */
        curbuf->b_op_end = curwin->w_cursor;    /* default for '] mark */
    }
#endif

    if (flags & PUT_LINE)       /* :put command or "p" in Visual line mode. */
        y_type = MLINE;

    if (y_size == 0 || y_array == NULL)
    {
        EMSG2(_("E353: Nothing in register %s"),
                  regname == 0 ? (char_u *)"\"" : transchar(regname));
        goto end;
    }

#ifdef FEAT_VISUAL
    if (y_type == MBLOCK)
    {
        lnum = curwin->w_cursor.lnum + y_size + 1;
        if (lnum > curbuf->b_ml.ml_line_count)
            lnum = curbuf->b_ml.ml_line_count + 1;
        if (u_save(curwin->w_cursor.lnum - 1, lnum) == FAIL)
            goto end;
    }
    else
#endif
        if (y_type == MLINE)
    {
        lnum = curwin->w_cursor.lnum;
#ifdef FEAT_FOLDING
        /* Correct line number for closed fold.  Don't move the cursor yet,
         * u_save() uses it. */
        if (dir == BACKWARD)
            (void)hasFolding(lnum, &lnum, NULL);
        else
            (void)hasFolding(lnum, NULL, &lnum);
#endif
        if (dir == FORWARD)
            ++lnum;
        if (u_save(lnum - 1, lnum) == FAIL)
            goto end;
#ifdef FEAT_FOLDING
        if (dir == FORWARD)
            curwin->w_cursor.lnum = lnum - 1;
        else
            curwin->w_cursor.lnum = lnum;
        curbuf->b_op_start = curwin->w_cursor;  /* for mark_adjust() */
#endif
    }
    else if (u_save_cursor() == FAIL)
        goto end;

    yanklen = (int)STRLEN(y_array[0]);

#ifdef FEAT_VIRTUALEDIT
    if (ve_flags == VE_ALL && y_type == MCHAR)
    {
        if (gchar_cursor() == TAB)
        {
            /* Don't need to insert spaces when "p" on the last position of a
             * tab or "P" on the first position. */
            if (dir == FORWARD
                    ? (int)curwin->w_cursor.coladd < curbuf->b_p_ts - 1
                                                : curwin->w_cursor.coladd > 0)
                coladvance_force(getviscol());
            else
                curwin->w_cursor.coladd = 0;
        }
        else if (curwin->w_cursor.coladd > 0 || gchar_cursor() == NUL)
            coladvance_force(getviscol() + (dir == FORWARD));
    }
#endif

    lnum = curwin->w_cursor.lnum;
    col = curwin->w_cursor.col;

#ifdef FEAT_VISUAL
    /*
     * Block mode
     */
    if (y_type == MBLOCK)
    {
        char    c = gchar_cursor();
        colnr_T endcol2 = 0;

        if (dir == FORWARD && c != NUL)
        {
#ifdef FEAT_VIRTUALEDIT
            if (ve_flags == VE_ALL)
                getvcol(curwin, &curwin->w_cursor, &col, NULL, &endcol2);
            else
#endif
                getvcol(curwin, &curwin->w_cursor, NULL, NULL, &col);

#ifdef FEAT_MBYTE
            if (has_mbyte)
                /* move to start of next multi-byte character */
                curwin->w_cursor.col += (*mb_ptr2len)(ml_get_cursor());
            else
#endif
#ifdef FEAT_VIRTUALEDIT
            if (c != TAB || ve_flags != VE_ALL)
#endif
                ++curwin->w_cursor.col;
            ++col;
        }
        else
            getvcol(curwin, &curwin->w_cursor, &col, NULL, &endcol2);

#ifdef FEAT_VIRTUALEDIT
        col += curwin->w_cursor.coladd;
        if (ve_flags == VE_ALL
                && (curwin->w_cursor.coladd > 0
                    || endcol2 == curwin->w_cursor.col))
        {
            if (dir == FORWARD && c == NUL)
                ++col;
            if (dir != FORWARD && c != NUL)
                ++curwin->w_cursor.col;
            if (c == TAB)
            {
                if (dir == BACKWARD && curwin->w_cursor.col)
                    curwin->w_cursor.col--;
                if (dir == FORWARD && col - 1 == endcol2)
                    curwin->w_cursor.col++;
            }
        }
        curwin->w_cursor.coladd = 0;
#endif
        bd.textcol = 0;
        for (i = 0; i < y_size; ++i)
        {
            int spaces;
            char shortline;

            bd.startspaces = 0;
            bd.endspaces = 0;
            vcol = 0;
            delcount = 0;

            /* add a new line */
            if (curwin->w_cursor.lnum > curbuf->b_ml.ml_line_count)
            {
                if (ml_append(curbuf->b_ml.ml_line_count, (char_u *)"",
                                                   (colnr_T)1, FALSE) == FAIL)
                    break;
                ++nr_lines;
            }
            /* get the old line and advance to the position to insert at */
            oldp = ml_get_curline();
            oldlen = (int)STRLEN(oldp);
            for (ptr = oldp; vcol < col && *ptr; )
            {
                /* Count a tab for what it's worth (if list mode not on) */
                incr = lbr_chartabsize_adv(&ptr, (colnr_T)vcol);
                vcol += incr;
            }
            bd.textcol = (colnr_T)(ptr - oldp);

            shortline = (vcol < col) || (vcol == col && !*ptr) ;

            if (vcol < col) /* line too short, padd with spaces */
                bd.startspaces = col - vcol;
            else if (vcol > col)
            {
                bd.endspaces = vcol - col;
                bd.startspaces = incr - bd.endspaces;
                --bd.textcol;
                delcount = 1;
#ifdef FEAT_MBYTE
                if (has_mbyte)
                    bd.textcol -= (*mb_head_off)(oldp, oldp + bd.textcol);
#endif
                if (oldp[bd.textcol] != TAB)
                {
                    /* Only a Tab can be split into spaces.  Other
                     * characters will have to be moved to after the
                     * block, causing misalignment. */
                    delcount = 0;
                    bd.endspaces = 0;
                }
            }

            yanklen = (int)STRLEN(y_array[i]);

            /* calculate number of spaces required to fill right side of block*/
            spaces = y_width + 1;
            for (j = 0; j < yanklen; j++)
                spaces -= lbr_chartabsize(&y_array[i][j], 0);
            if (spaces < 0)
                spaces = 0;

            /* insert the new text */
            totlen = count * (yanklen + spaces) + bd.startspaces + bd.endspaces;
            newp = alloc_check((unsigned)totlen + oldlen + 1);
            if (newp == NULL)
                break;
            /* copy part up to cursor to new line */
            ptr = newp;
            mch_memmove(ptr, oldp, (size_t)bd.textcol);
            ptr += bd.textcol;
            /* may insert some spaces before the new text */
            copy_spaces(ptr, (size_t)bd.startspaces);
            ptr += bd.startspaces;
            /* insert the new text */
            for (j = 0; j < count; ++j)
            {
                mch_memmove(ptr, y_array[i], (size_t)yanklen);
                ptr += yanklen;

                /* insert block's trailing spaces only if there's text behind */
                if ((j < count - 1 || !shortline) && spaces)
                {
                    copy_spaces(ptr, (size_t)spaces);
                    ptr += spaces;
                }
            }
            /* may insert some spaces after the new text */
            copy_spaces(ptr, (size_t)bd.endspaces);
            ptr += bd.endspaces;
            /* move the text after the cursor to the end of the line. */
            mch_memmove(ptr, oldp + bd.textcol + delcount,
                                (size_t)(oldlen - bd.textcol - delcount + 1));
            ml_replace(curwin->w_cursor.lnum, newp, FALSE);

            ++curwin->w_cursor.lnum;
            if (i == 0)
                curwin->w_cursor.col += bd.startspaces;
        }

        changed_lines(lnum, 0, curwin->w_cursor.lnum, nr_lines);

        /* Set '[ mark. */
        curbuf->b_op_start = curwin->w_cursor;
        curbuf->b_op_start.lnum = lnum;

        /* adjust '] mark */
        curbuf->b_op_end.lnum = curwin->w_cursor.lnum - 1;
        curbuf->b_op_end.col = bd.textcol + totlen - 1;
# ifdef FEAT_VIRTUALEDIT
        curbuf->b_op_end.coladd = 0;
# endif
        if (flags & PUT_CURSEND)
        {
            colnr_T len;

            curwin->w_cursor = curbuf->b_op_end;
            curwin->w_cursor.col++;

            /* in Insert mode we might be after the NUL, correct for that */
            len = (colnr_T)STRLEN(ml_get_curline());
            if (curwin->w_cursor.col > len)
                curwin->w_cursor.col = len;
        }
        else
            curwin->w_cursor.lnum = lnum;
    }
    else
#endif
    {
        /*
         * Character or Line mode
         */
        if (y_type == MCHAR)
        {
            /* if type is MCHAR, FORWARD is the same as BACKWARD on the next
             * char */
            if (dir == FORWARD && gchar_cursor() != NUL)
            {
#ifdef FEAT_MBYTE
                if (has_mbyte)
                {
                    int bytelen = (*mb_ptr2len)(ml_get_cursor());

                    /* put it on the next of the multi-byte character. */
                    col += bytelen;
                    if (yanklen)
                    {
                        curwin->w_cursor.col += bytelen;
                        curbuf->b_op_end.col += bytelen;
                    }
                }
                else
#endif
                {
                    ++col;
                    if (yanklen)
                    {
                        ++curwin->w_cursor.col;
                        ++curbuf->b_op_end.col;
                    }
                }
            }
            curbuf->b_op_start = curwin->w_cursor;
        }
        /*
         * Line mode: BACKWARD is the same as FORWARD on the previous line
         */
        else if (dir == BACKWARD)
            --lnum;
        new_cursor = curwin->w_cursor;

        /*
         * simple case: insert into current line
         */
        if (y_type == MCHAR && y_size == 1)
        {
            totlen = count * yanklen;
            if (totlen)
            {
                oldp = ml_get(lnum);
                newp = alloc_check((unsigned)(STRLEN(oldp) + totlen + 1));
                if (newp == NULL)
                    goto end;           /* alloc() will give error message */
                mch_memmove(newp, oldp, (size_t)col);
                ptr = newp + col;
                for (i = 0; i < count; ++i)
                {
                    mch_memmove(ptr, y_array[0], (size_t)yanklen);
                    ptr += yanklen;
                }
                STRMOVE(ptr, oldp + col);
                ml_replace(lnum, newp, FALSE);
                /* Put cursor on last putted char. */
                curwin->w_cursor.col += (colnr_T)(totlen - 1);
            }
            curbuf->b_op_end = curwin->w_cursor;
            /* For "CTRL-O p" in Insert mode, put cursor after last char */
            if (totlen && (restart_edit != 0 || (flags & PUT_CURSEND)))
                ++curwin->w_cursor.col;
            changed_bytes(lnum, col);
        }
        else
        {
            /*
             * Insert at least one line.  When y_type is MCHAR, break the first
             * line in two.
             */
            for (cnt = 1; cnt <= count; ++cnt)
            {
                i = 0;
                if (y_type == MCHAR)
                {
                    /*
                     * Split the current line in two at the insert position.
                     * First insert y_array[size - 1] in front of second line.
                     * Then append y_array[0] to first line.
                     */
                    lnum = new_cursor.lnum;
                    ptr = ml_get(lnum) + col;
                    totlen = (int)STRLEN(y_array[y_size - 1]);
                    newp = alloc_check((unsigned)(STRLEN(ptr) + totlen + 1));
                    if (newp == NULL)
                        goto error;
                    STRCPY(newp, y_array[y_size - 1]);
                    STRCAT(newp, ptr);
                    /* insert second line */
                    ml_append(lnum, newp, (colnr_T)0, FALSE);
                    vim_free(newp);

                    oldp = ml_get(lnum);
                    newp = alloc_check((unsigned)(col + yanklen + 1));
                    if (newp == NULL)
                        goto error;
                                            /* copy first part of line */
                    mch_memmove(newp, oldp, (size_t)col);
                                            /* append to first line */
                    mch_memmove(newp + col, y_array[0], (size_t)(yanklen + 1));
                    ml_replace(lnum, newp, FALSE);

                    curwin->w_cursor.lnum = lnum;
                    i = 1;
                }

                for (; i < y_size; ++i)
                {
                    if ((y_type != MCHAR || i < y_size - 1)
                            && ml_append(lnum, y_array[i], (colnr_T)0, FALSE)
                                                                      == FAIL)
                            goto error;
                    lnum++;
                    ++nr_lines;
                    if (flags & PUT_FIXINDENT)
                    {
                        old_pos = curwin->w_cursor;
                        curwin->w_cursor.lnum = lnum;
                        ptr = ml_get(lnum);
                        if (cnt == count && i == y_size - 1)
                            lendiff = (int)STRLEN(ptr);
#if defined(FEAT_SMARTINDENT) || defined(FEAT_CINDENT)
                        if (*ptr == '#' && preprocs_left())
                            indent = 0;     /* Leave # lines at start */
                        else
#endif
                             if (*ptr == NUL)
                            indent = 0;     /* Ignore empty lines */
                        else if (first_indent)
                        {
                            indent_diff = orig_indent - get_indent();
                            indent = orig_indent;
                            first_indent = FALSE;
                        }
                        else if ((indent = get_indent() + indent_diff) < 0)
                            indent = 0;
                        (void)set_indent(indent, 0);
                        curwin->w_cursor = old_pos;
                        /* remember how many chars were removed */
                        if (cnt == count && i == y_size - 1)
                            lendiff -= (int)STRLEN(ml_get(lnum));
                    }
                }
            }

error:
            /* Adjust marks. */
            if (y_type == MLINE)
            {
                curbuf->b_op_start.col = 0;
                if (dir == FORWARD)
                    curbuf->b_op_start.lnum++;
            }
            mark_adjust(curbuf->b_op_start.lnum + (y_type == MCHAR),
                                             (linenr_T)MAXLNUM, nr_lines, 0L);

            /* note changed text for displaying and folding */
            if (y_type == MCHAR)
                changed_lines(curwin->w_cursor.lnum, col,
                                         curwin->w_cursor.lnum + 1, nr_lines);
            else
                changed_lines(curbuf->b_op_start.lnum, 0,
                                           curbuf->b_op_start.lnum, nr_lines);

            /* put '] mark at last inserted character */
            curbuf->b_op_end.lnum = lnum;
            /* correct length for change in indent */
            col = (colnr_T)STRLEN(y_array[y_size - 1]) - lendiff;
            if (col > 1)
                curbuf->b_op_end.col = col - 1;
            else
                curbuf->b_op_end.col = 0;

            if (flags & PUT_CURSLINE)
            {
                /* ":put": put cursor on last inserted line */
                curwin->w_cursor.lnum = lnum;
                beginline(BL_WHITE | BL_FIX);
            }
            else if (flags & PUT_CURSEND)
            {
                /* put cursor after inserted text */
                if (y_type == MLINE)
                {
                    if (lnum >= curbuf->b_ml.ml_line_count)
                        curwin->w_cursor.lnum = curbuf->b_ml.ml_line_count;
                    else
                        curwin->w_cursor.lnum = lnum + 1;
                    curwin->w_cursor.col = 0;
                }
                else
                {
                    curwin->w_cursor.lnum = lnum;
                    curwin->w_cursor.col = col;
                }
            }
            else if (y_type == MLINE)
            {
                /* put cursor on first non-blank in first inserted line */
                curwin->w_cursor.col = 0;
                if (dir == FORWARD)
                    ++curwin->w_cursor.lnum;
                beginline(BL_WHITE | BL_FIX);
            }
            else        /* put cursor on first inserted character */
                curwin->w_cursor = new_cursor;
        }
    }

    msgmore(nr_lines);
    curwin->w_set_curswant = TRUE;

end:
    if (allocated)
        vim_free(insert_string);
    if (regname == '=')
        vim_free(y_array);

    /* If the cursor is past the end of the line put it at the end. */
    adjust_cursor_eol();
}

/*
 * When the cursor is on the NUL past the end of the line and it should not be
 * there move it left.
 */
    void
adjust_cursor_eol()
{
    if (curwin->w_cursor.col > 0
            && gchar_cursor() == NUL
#ifdef FEAT_VIRTUALEDIT
            && (ve_flags & VE_ONEMORE) == 0
#endif
            && !(restart_edit || (State & INSERT)))
    {
        /* Put the cursor on the last character in the line. */
        dec_cursor();

#ifdef FEAT_VIRTUALEDIT
        if (ve_flags == VE_ALL)
        {
            colnr_T         scol, ecol;

            /* Coladd is set to the width of the last character. */
            getvcol(curwin, &curwin->w_cursor, &scol, NULL, &ecol);
            curwin->w_cursor.coladd = ecol - scol + 1;
        }
#endif
    }
}

#if defined(FEAT_SMARTINDENT) || defined(FEAT_CINDENT) || defined(PROTO)
/*
 * Return TRUE if lines starting with '#' should be left aligned.
 */
    int
preprocs_left()
{
    return
# ifdef FEAT_SMARTINDENT
#  ifdef FEAT_CINDENT
        (curbuf->b_p_si && !curbuf->b_p_cin) ||
#  else
        curbuf->b_p_si
#  endif
# endif
# ifdef FEAT_CINDENT
        (curbuf->b_p_cin && in_cinkeys('#', ' ', TRUE))
# endif
        ;
}
#endif

/* Return the character name of the register with the given number */
    int
get_register_name(num)
    int num;
{
    if (num == -1)
        return '"';
    else if (num < 10)
        return num + '0';
    else if (num == DELETION_REGISTER)
        return '-';
#ifdef FEAT_CLIPBOARD
    else if (num == STAR_REGISTER)
        return '*';
    else if (num == PLUS_REGISTER)
        return '+';
#endif
    else
    {
#ifdef EBCDIC
        int i;

        /* EBCDIC is really braindead ... */
        i = 'a' + (num - 10);
        if (i > 'i')
            i += 7;
        if (i > 'r')
            i += 8;
        return i;
#else
        return num + 'a' - 10;
#endif
    }
}

/*
 * ":dis" and ":registers": Display the contents of the yank registers.
 */
    void
ex_display(eap)
    exarg_T     *eap;
{
    int                 i, n;
    long                j;
    char_u              *p;
    struct yankreg      *yb;
    int                 name;
    int                 attr;
    char_u              *arg = eap->arg;
#ifdef FEAT_MBYTE
    int                 clen;
#else
# define clen 1
#endif

    if (arg != NULL && *arg == NUL)
        arg = NULL;
    attr = hl_attr(HLF_8);

    /* Highlight title */
    MSG_PUTS_TITLE(_("\n--- Registers ---"));
    for (i = -1; i < NUM_REGISTERS && !got_int; ++i)
    {
        name = get_register_name(i);
        if (arg != NULL && vim_strchr(arg, name) == NULL)
            continue;       /* did not ask for this register */

#ifdef FEAT_CLIPBOARD
        /* Adjust register name for "unnamed" in 'clipboard'.
         * When it's a clipboard register, fill it with the current contents
         * of the clipboard.  */
        adjust_clip_reg(&name);
        (void)may_get_selection(name);
#endif

        if (i == -1)
        {
            if (y_previous != NULL)
                yb = y_previous;
            else
                yb = &(y_regs[0]);
        }
        else
            yb = &(y_regs[i]);
        if (yb->y_array != NULL)
        {
            msg_putchar('\n');
            msg_putchar('"');
            msg_putchar(name);
            MSG_PUTS("   ");

            n = (int)Columns - 6;
            for (j = 0; j < yb->y_size && n > 1; ++j)
            {
                if (j)
                {
                    MSG_PUTS_ATTR("^J", attr);
                    n -= 2;
                }
                for (p = yb->y_array[j]; *p && (n -= ptr2cells(p)) >= 0; ++p)
                {
#ifdef FEAT_MBYTE
                    clen = (*mb_ptr2len)(p);
#endif
                    msg_outtrans_len(p, clen);
#ifdef FEAT_MBYTE
                    p += clen - 1;
#endif
                }
            }
            if (n > 1 && yb->y_type == MLINE)
                MSG_PUTS_ATTR("^J", attr);
            out_flush();                    /* show one line at a time */
        }
        ui_breakcheck();
    }

    /*
     * display last inserted text
     */
    if ((p = get_last_insert()) != NULL
                 && (arg == NULL || vim_strchr(arg, '.') != NULL) && !got_int)
    {
        MSG_PUTS("\n\".   ");
        dis_msg(p, TRUE);
    }

    /*
     * display last command line
     */
    if (last_cmdline != NULL && (arg == NULL || vim_strchr(arg, ':') != NULL)
                                                                  && !got_int)
    {
        MSG_PUTS("\n\":   ");
        dis_msg(last_cmdline, FALSE);
    }

    /*
     * display current file name
     */
    if (curbuf->b_fname != NULL
            && (arg == NULL || vim_strchr(arg, '%') != NULL) && !got_int)
    {
        MSG_PUTS("\n\"%   ");
        dis_msg(curbuf->b_fname, FALSE);
    }

    /*
     * display alternate file name
     */
    if ((arg == NULL || vim_strchr(arg, '%') != NULL) && !got_int)
    {
        char_u      *fname;
        linenr_T    dummy;

        if (buflist_name_nr(0, &fname, &dummy) != FAIL)
        {
            MSG_PUTS("\n\"#   ");
            dis_msg(fname, FALSE);
        }
    }

    /*
     * display last search pattern
     */
    if (last_search_pat() != NULL
                 && (arg == NULL || vim_strchr(arg, '/') != NULL) && !got_int)
    {
        MSG_PUTS("\n\"/   ");
        dis_msg(last_search_pat(), FALSE);
    }

#ifdef FEAT_EVAL
    /*
     * display last used expression
     */
    if (expr_line != NULL && (arg == NULL || vim_strchr(arg, '=') != NULL)
                                                                  && !got_int)
    {
        MSG_PUTS("\n\"=   ");
        dis_msg(expr_line, FALSE);
    }
#endif
}

/*
 * display a string for do_dis()
 * truncate at end of screen line
 */
    static void
dis_msg(p, skip_esc)
    char_u      *p;
    int         skip_esc;           /* if TRUE, ignore trailing ESC */
{
    int         n;
#ifdef FEAT_MBYTE
    int         l;
#endif

    n = (int)Columns - 6;
    while (*p != NUL
            && !(*p == ESC && skip_esc && *(p + 1) == NUL)
            && (n -= ptr2cells(p)) >= 0)
    {
#ifdef FEAT_MBYTE
        if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
        {
            msg_outtrans_len(p, l);
            p += l;
        }
        else
#endif
            msg_outtrans_len(p++, 1);
    }
    ui_breakcheck();
}

/*
 * join 'count' lines (minimal 2), including u_save()
 */
    void
do_do_join(count, insert_space)
    long    count;
    int     insert_space;
{
    colnr_T     col = MAXCOL;

    if (u_save((linenr_T)(curwin->w_cursor.lnum - 1),
                    (linenr_T)(curwin->w_cursor.lnum + count)) == FAIL)
        return;

    while (--count > 0)
    {
        line_breakcheck();
        if (got_int || do_join(insert_space) == FAIL)
        {
            beep_flush();
            break;
        }
        if (col == MAXCOL && vim_strchr(p_cpo, CPO_JOINCOL) != NULL)
            col = curwin->w_cursor.col;
    }

    /* Vi compatible: use the column of the first join */
    if (col != MAXCOL && vim_strchr(p_cpo, CPO_JOINCOL) != NULL)
        curwin->w_cursor.col = col;

#if 0
    /*
     * Need to update the screen if the line where the cursor is became too
     * long to fit on the screen.
     */
    update_topline_redraw();
#endif
}

/*
 * Join two lines at the cursor position.
 * "redraw" is TRUE when the screen should be updated.
 * Caller must have setup for undo.
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_join(insert_space)
    int         insert_space;
{
    char_u      *curr;
    char_u      *next, *next_start;
    char_u      *newp;
    int         endcurr1, endcurr2;
    int         currsize;       /* size of the current line */
    int         nextsize;       /* size of the next line */
    int         spaces;         /* number of spaces to insert */
    linenr_T    t;

    if (curwin->w_cursor.lnum == curbuf->b_ml.ml_line_count)
        return FAIL;            /* can't join on last line */

    curr = ml_get_curline();
    currsize = (int)STRLEN(curr);
    endcurr1 = endcurr2 = NUL;
    if (insert_space && currsize > 0)
    {
#ifdef FEAT_MBYTE
        if (has_mbyte)
        {
            next = curr + currsize;
            mb_ptr_back(curr, next);
            endcurr1 = (*mb_ptr2char)(next);
            if (next > curr)
            {
                mb_ptr_back(curr, next);
                endcurr2 = (*mb_ptr2char)(next);
            }
        }
        else
#endif
        {
            endcurr1 = *(curr + currsize - 1);
            if (currsize > 1)
                endcurr2 = *(curr + currsize - 2);
        }
    }

    next = next_start = ml_get((linenr_T)(curwin->w_cursor.lnum + 1));
    spaces = 0;
    if (insert_space)
    {
        next = skipwhite(next);
        if (*next != ')' && currsize != 0 && endcurr1 != TAB
#ifdef FEAT_MBYTE
                && (!has_format_option(FO_MBYTE_JOIN)
                        || (mb_ptr2char(next) < 0x100 && endcurr1 < 0x100))
                && (!has_format_option(FO_MBYTE_JOIN2)
                        || mb_ptr2char(next) < 0x100 || endcurr1 < 0x100)
#endif
                )
        {
            /* don't add a space if the line is ending in a space */
            if (endcurr1 == ' ')
                endcurr1 = endcurr2;
            else
                ++spaces;
            /* extra space when 'joinspaces' set and line ends in '.' */
            if (       p_js
                    && (endcurr1 == '.'
                        || (vim_strchr(p_cpo, CPO_JOINSP) == NULL
                            && (endcurr1 == '?' || endcurr1 == '!'))))
                ++spaces;
        }
    }
    nextsize = (int)STRLEN(next);

    newp = alloc_check((unsigned)(currsize + nextsize + spaces + 1));
    if (newp == NULL)
        return FAIL;

    /*
     * Insert the next line first, because we already have that pointer.
     * Curr has to be obtained again, because getting next will have
     * invalidated it.
     */
    mch_memmove(newp + currsize + spaces, next, (size_t)(nextsize + 1));

    curr = ml_get_curline();
    mch_memmove(newp, curr, (size_t)currsize);

    copy_spaces(newp + currsize, (size_t)spaces);

    ml_replace(curwin->w_cursor.lnum, newp, FALSE);

    /* Only report the change in the first line here, del_lines() will report
     * the deleted line. */
    changed_lines(curwin->w_cursor.lnum, currsize,
                                               curwin->w_cursor.lnum + 1, 0L);

    /*
     * Delete the following line. To do this we move the cursor there
     * briefly, and then move it back. After del_lines() the cursor may
     * have moved up (last line deleted), so the current lnum is kept in t.
     *
     * Move marks from the deleted line to the joined line, adjusting the
     * column.  This is not Vi compatible, but Vi deletes the marks, thus that
     * should not really be a problem.
     */
    t = curwin->w_cursor.lnum;
    mark_col_adjust(t + 1, (colnr_T)0, (linenr_T)-1,
                             (long)(currsize + spaces - (next - next_start)));
    ++curwin->w_cursor.lnum;
    del_lines(1L, FALSE);
    curwin->w_cursor.lnum = t;

    /*
     * go to first character of the joined line
     */
    curwin->w_cursor.col = currsize;
    check_cursor_col();
#ifdef FEAT_VIRTUALEDIT
    curwin->w_cursor.coladd = 0;
#endif
    curwin->w_set_curswant = TRUE;

    return OK;
}

#ifdef FEAT_COMMENTS
/*
 * Return TRUE if the two comment leaders given are the same.  "lnum" is
 * the first line.  White-space is ignored.  Note that the whole of
 * 'leader1' must match 'leader2_len' characters from 'leader2' -- webb
 */
    static int
same_leader(lnum, leader1_len, leader1_flags, leader2_len, leader2_flags)
    linenr_T lnum;
    int     leader1_len;
    char_u  *leader1_flags;
    int     leader2_len;
    char_u  *leader2_flags;
{
    int     idx1 = 0, idx2 = 0;
    char_u  *p;
    char_u  *line1;
    char_u  *line2;

    if (leader1_len == 0)
        return (leader2_len == 0);

    /*
     * If first leader has 'f' flag, the lines can be joined only if the
     * second line does not have a leader.
     * If first leader has 'e' flag, the lines can never be joined.
     * If fist leader has 's' flag, the lines can only be joined if there is
     * some text after it and the second line has the 'm' flag.
     */
    if (leader1_flags != NULL)
    {
        for (p = leader1_flags; *p && *p != ':'; ++p)
        {
            if (*p == COM_FIRST)
                return (leader2_len == 0);
            if (*p == COM_END)
                return FALSE;
            if (*p == COM_START)
            {
                if (*(ml_get(lnum) + leader1_len) == NUL)
                    return FALSE;
                if (leader2_flags == NULL || leader2_len == 0)
                    return FALSE;
                for (p = leader2_flags; *p && *p != ':'; ++p)
                    if (*p == COM_MIDDLE)
                        return TRUE;
                return FALSE;
            }
        }
    }

    /*
     * Get current line and next line, compare the leaders.
     * The first line has to be saved, only one line can be locked at a time.
     */
    line1 = vim_strsave(ml_get(lnum));
    if (line1 != NULL)
    {
        for (idx1 = 0; vim_iswhite(line1[idx1]); ++idx1)
            ;
        line2 = ml_get(lnum + 1);
        for (idx2 = 0; idx2 < leader2_len; ++idx2)
        {
            if (!vim_iswhite(line2[idx2]))
            {
                if (line1[idx1++] != line2[idx2])
                    break;
            }
            else
                while (vim_iswhite(line1[idx1]))
                    ++idx1;
        }
        vim_free(line1);
    }
    return (idx2 == leader2_len && idx1 == leader1_len);
}
#endif

/*
 * implementation of the format operator 'gq'
 */
    void
op_format(oap, keep_cursor)
    oparg_T     *oap;
    int         keep_cursor;            /* keep cursor on same text char */
{
    long        old_line_count = curbuf->b_ml.ml_line_count;

    /* Place the cursor where the "gq" or "gw" command was given, so that "u"
     * can put it back there. */
    curwin->w_cursor = oap->cursor_start;

    if (u_save((linenr_T)(oap->start.lnum - 1),
                                       (linenr_T)(oap->end.lnum + 1)) == FAIL)
        return;
    curwin->w_cursor = oap->start;

#ifdef FEAT_VISUAL
    if (oap->is_VIsual)
        /* When there is no change: need to remove the Visual selection */
        redraw_curbuf_later(INVERTED);
#endif

    /* Set '[ mark at the start of the formatted area */
    curbuf->b_op_start = oap->start;

    /* For "gw" remember the cursor position and put it back below (adjusted
     * for joined and split lines). */
    if (keep_cursor)
        saved_cursor = oap->cursor_start;

    format_lines(oap->line_count, keep_cursor);

    /*
     * Leave the cursor at the first non-blank of the last formatted line.
     * If the cursor was moved one line back (e.g. with "Q}") go to the next
     * line, so "." will do the next lines.
     */
    if (oap->end_adjusted && curwin->w_cursor.lnum < curbuf->b_ml.ml_line_count)
        ++curwin->w_cursor.lnum;
    beginline(BL_WHITE | BL_FIX);
    old_line_count = curbuf->b_ml.ml_line_count - old_line_count;
    msgmore(old_line_count);

    /* put '] mark on the end of the formatted area */
    curbuf->b_op_end = curwin->w_cursor;

    if (keep_cursor)
    {
        curwin->w_cursor = saved_cursor;
        saved_cursor.lnum = 0;
    }

#ifdef FEAT_VISUAL
    if (oap->is_VIsual)
    {
        win_T   *wp;

        FOR_ALL_WINDOWS(wp)
        {
            if (wp->w_old_cursor_lnum != 0)
            {
                /* When lines have been inserted or deleted, adjust the end of
                 * the Visual area to be redrawn. */
                if (wp->w_old_cursor_lnum > wp->w_old_visual_lnum)
                    wp->w_old_cursor_lnum += old_line_count;
                else
                    wp->w_old_visual_lnum += old_line_count;
            }
        }
    }
#endif
}

#if defined(FEAT_EVAL) || defined(PROTO)
/*
 * Implementation of the format operator 'gq' for when using 'formatexpr'.
 */
    void
op_formatexpr(oap)
    oparg_T     *oap;
{
# ifdef FEAT_VISUAL
    if (oap->is_VIsual)
        /* When there is no change: need to remove the Visual selection */
        redraw_curbuf_later(INVERTED);
# endif

    (void)fex_format(oap->start.lnum, oap->line_count, NUL);
}

    int
fex_format(lnum, count, c)
    linenr_T    lnum;
    long        count;
    int         c;      /* character to be inserted */
{
    int         use_sandbox = was_set_insecurely((char_u *)"formatexpr",
                                                                   OPT_LOCAL);
    int         r;
#ifdef FEAT_MBYTE
    char_u      buf[MB_MAXBYTES];
#else
    char_u      buf[2];
#endif

    /*
     * Set v:lnum to the first line number and v:count to the number of lines.
     * Set v:char to the character to be inserted (can be NUL).
     */
    set_vim_var_nr(VV_LNUM, lnum);
    set_vim_var_nr(VV_COUNT, count);

#ifdef FEAT_MBYTE
    if (has_mbyte)
        buf[(*mb_char2bytes)(c, buf)] = NUL;
    else
#endif
    {
        buf[0] = c;
        buf[1] = NUL;
    }
    set_vim_var_string(VV_CHAR, buf, -1);

    /*
     * Evaluate the function.
     */
    if (use_sandbox)
        ++sandbox;
    r = eval_to_number(curbuf->b_p_fex);
    if (use_sandbox)
        --sandbox;

    set_vim_var_string(VV_CHAR, NULL, -1);

    return r;
}
#endif

/*
 * Format "line_count" lines, starting at the cursor position.
 * When "line_count" is negative, format until the end of the paragraph.
 * Lines after the cursor line are saved for undo, caller must have saved the
 * first line.
 */
    void
format_lines(line_count, avoid_fex)
    linenr_T    line_count;
    int         avoid_fex;              /* don't use 'formatexpr' */
{
    int         max_len;
    int         is_not_par;             /* current line not part of parag. */
    int         next_is_not_par;        /* next line not part of paragraph */
    int         is_end_par;             /* at end of paragraph */
    int         prev_is_end_par = FALSE;/* prev. line not part of parag. */
    int         next_is_start_par = FALSE;
#ifdef FEAT_COMMENTS
    int         leader_len = 0;         /* leader len of current line */
    int         next_leader_len;        /* leader len of next line */
    char_u      *leader_flags = NULL;   /* flags for leader of current line */
    char_u      *next_leader_flags;     /* flags for leader of next line */
    int         do_comments;            /* format comments */
#endif
    int         advance = TRUE;
    int         second_indent = -1;
    int         do_second_indent;
    int         do_number_indent;
    int         do_trail_white;
    int         first_par_line = TRUE;
    int         smd_save;
    long        count;
    int         need_set_indent = TRUE; /* set indent of next paragraph */
    int         force_format = FALSE;
    int         old_State = State;

    /* length of a line to force formatting: 3 * 'tw' */
    max_len = comp_textwidth(TRUE) * 3;

    /* check for 'q', '2' and '1' in 'formatoptions' */
#ifdef FEAT_COMMENTS
    do_comments = has_format_option(FO_Q_COMS);
#endif
    do_second_indent = has_format_option(FO_Q_SECOND);
    do_number_indent = has_format_option(FO_Q_NUMBER);
    do_trail_white = has_format_option(FO_WHITE_PAR);

    /*
     * Get info about the previous and current line.
     */
    if (curwin->w_cursor.lnum > 1)
        is_not_par = fmt_check_par(curwin->w_cursor.lnum - 1
#ifdef FEAT_COMMENTS
                                , &leader_len, &leader_flags, do_comments
#endif
                                );
    else
        is_not_par = TRUE;
    next_is_not_par = fmt_check_par(curwin->w_cursor.lnum
#ifdef FEAT_COMMENTS
                           , &next_leader_len, &next_leader_flags, do_comments
#endif
                                );
    is_end_par = (is_not_par || next_is_not_par);
    if (!is_end_par && do_trail_white)
        is_end_par = !ends_in_white(curwin->w_cursor.lnum - 1);

    curwin->w_cursor.lnum--;
    for (count = line_count; count != 0 && !got_int; --count)
    {
        /*
         * Advance to next paragraph.
         */
        if (advance)
        {
            curwin->w_cursor.lnum++;
            prev_is_end_par = is_end_par;
            is_not_par = next_is_not_par;
#ifdef FEAT_COMMENTS
            leader_len = next_leader_len;
            leader_flags = next_leader_flags;
#endif
        }

        /*
         * The last line to be formatted.
         */
        if (count == 1 || curwin->w_cursor.lnum == curbuf->b_ml.ml_line_count)
        {
            next_is_not_par = TRUE;
#ifdef FEAT_COMMENTS
            next_leader_len = 0;
            next_leader_flags = NULL;
#endif
        }
        else
        {
            next_is_not_par = fmt_check_par(curwin->w_cursor.lnum + 1
#ifdef FEAT_COMMENTS
                           , &next_leader_len, &next_leader_flags, do_comments
#endif
                                        );
            if (do_number_indent)
                next_is_start_par =
                           (get_number_indent(curwin->w_cursor.lnum + 1) > 0);
        }
        advance = TRUE;
        is_end_par = (is_not_par || next_is_not_par || next_is_start_par);
        if (!is_end_par && do_trail_white)
            is_end_par = !ends_in_white(curwin->w_cursor.lnum);

        /*
         * Skip lines that are not in a paragraph.
         */
        if (is_not_par)
        {
            if (line_count < 0)
                break;
        }
        else
        {
            /*
             * For the first line of a paragraph, check indent of second line.
             * Don't do this for comments and empty lines.
             */
            if (first_par_line
                    && (do_second_indent || do_number_indent)
                    && prev_is_end_par
                    && curwin->w_cursor.lnum < curbuf->b_ml.ml_line_count
#ifdef FEAT_COMMENTS
                    && leader_len == 0
                    && next_leader_len == 0
#endif
                    )
            {
                if (do_second_indent
                        && !lineempty(curwin->w_cursor.lnum + 1))
                    second_indent = get_indent_lnum(curwin->w_cursor.lnum + 1);
                else if (do_number_indent)
                    second_indent = get_number_indent(curwin->w_cursor.lnum);
            }

            /*
             * When the comment leader changes, it's the end of the paragraph.
             */
            if (curwin->w_cursor.lnum >= curbuf->b_ml.ml_line_count
#ifdef FEAT_COMMENTS
                    || !same_leader(curwin->w_cursor.lnum,
                                        leader_len, leader_flags,
                                          next_leader_len, next_leader_flags)
#endif
                    )
                is_end_par = TRUE;

            /*
             * If we have got to the end of a paragraph, or the line is
             * getting long, format it.
             */
            if (is_end_par || force_format)
            {
                if (need_set_indent)
                    /* replace indent in first line with minimal number of
                     * tabs and spaces, according to current options */
                    (void)set_indent(get_indent(), SIN_CHANGED);

                /* put cursor on last non-space */
                State = NORMAL; /* don't go past end-of-line */
                coladvance((colnr_T)MAXCOL);
                while (curwin->w_cursor.col && vim_isspace(gchar_cursor()))
                    dec_cursor();

                /* do the formatting, without 'showmode' */
                State = INSERT; /* for open_line() */
                smd_save = p_smd;
                p_smd = FALSE;
                insertchar(NUL, INSCHAR_FORMAT
#ifdef FEAT_COMMENTS
                        + (do_comments ? INSCHAR_DO_COM : 0)
#endif
                        + (avoid_fex ? INSCHAR_NO_FEX : 0), second_indent);
                State = old_State;
                p_smd = smd_save;
                second_indent = -1;
                /* at end of par.: need to set indent of next par. */
                need_set_indent = is_end_par;
                if (is_end_par)
                {
                    /* When called with a negative line count, break at the
                     * end of the paragraph. */
                    if (line_count < 0)
                        break;
                    first_par_line = TRUE;
                }
                force_format = FALSE;
            }

            /*
             * When still in same paragraph, join the lines together.  But
             * first delete the comment leader from the second line.
             */
            if (!is_end_par)
            {
                advance = FALSE;
                curwin->w_cursor.lnum++;
                curwin->w_cursor.col = 0;
                if (line_count < 0 && u_save_cursor() == FAIL)
                        break;
#ifdef FEAT_COMMENTS
                (void)del_bytes((long)next_leader_len, FALSE, FALSE);
                if (next_leader_len > 0)
                    mark_col_adjust(curwin->w_cursor.lnum, (colnr_T)0, 0L,
                                                      (long)-next_leader_len);
#endif
                curwin->w_cursor.lnum--;
                if (do_join(TRUE) == FAIL)
                {
                    beep_flush();
                    break;
                }
                first_par_line = FALSE;
                /* If the line is getting long, format it next time */
                if (STRLEN(ml_get_curline()) > (size_t)max_len)
                    force_format = TRUE;
                else
                    force_format = FALSE;
            }
        }
        line_breakcheck();
    }
}

/*
 * Return TRUE if line "lnum" ends in a white character.
 */
    static int
ends_in_white(lnum)
    linenr_T    lnum;
{
    char_u      *s = ml_get(lnum);
    size_t      l;

    if (*s == NUL)
        return FALSE;
    /* Don't use STRLEN() inside vim_iswhite(), SAS/C complains: "macro
     * invocation may call function multiple times". */
    l = STRLEN(s) - 1;
    return vim_iswhite(s[l]);
}

/*
 * Blank lines, and lines containing only the comment leader, are left
 * untouched by the formatting.  The function returns TRUE in this
 * case.  It also returns TRUE when a line starts with the end of a comment
 * ('e' in comment flags), so that this line is skipped, and not joined to the
 * previous line.  A new paragraph starts after a blank line, or when the
 * comment leader changes -- webb.
 */
#ifdef FEAT_COMMENTS
    static int
fmt_check_par(lnum, leader_len, leader_flags, do_comments)
    linenr_T    lnum;
    int         *leader_len;
    char_u      **leader_flags;
    int         do_comments;
{
    char_u      *flags = NULL;      /* init for GCC */
    char_u      *ptr;

    ptr = ml_get(lnum);
    if (do_comments)
        *leader_len = get_leader_len(ptr, leader_flags, FALSE);
    else
        *leader_len = 0;

    if (*leader_len > 0)
    {
        /*
         * Search for 'e' flag in comment leader flags.
         */
        flags = *leader_flags;
        while (*flags && *flags != ':' && *flags != COM_END)
            ++flags;
    }

    return (*skipwhite(ptr + *leader_len) == NUL
            || (*leader_len > 0 && *flags == COM_END)
            || startPS(lnum, NUL, FALSE));
}
#else
    static int
fmt_check_par(lnum)
    linenr_T    lnum;
{
    return (*skipwhite(ml_get(lnum)) == NUL || startPS(lnum, NUL, FALSE));
}
#endif

/*
 * Return TRUE when a paragraph starts in line "lnum".  Return FALSE when the
 * previous line is in the same paragraph.  Used for auto-formatting.
 */
    int
paragraph_start(lnum)
    linenr_T    lnum;
{
    char_u      *p;
#ifdef FEAT_COMMENTS
    int         leader_len = 0;         /* leader len of current line */
    char_u      *leader_flags = NULL;   /* flags for leader of current line */
    int         next_leader_len;        /* leader len of next line */
    char_u      *next_leader_flags;     /* flags for leader of next line */
    int         do_comments;            /* format comments */
#endif

    if (lnum <= 1)
        return TRUE;            /* start of the file */

    p = ml_get(lnum - 1);
    if (*p == NUL)
        return TRUE;            /* after empty line */

#ifdef FEAT_COMMENTS
    do_comments = has_format_option(FO_Q_COMS);
#endif
    if (fmt_check_par(lnum - 1
#ifdef FEAT_COMMENTS
                                , &leader_len, &leader_flags, do_comments
#endif
                ))
        return TRUE;            /* after non-paragraph line */

    if (fmt_check_par(lnum
#ifdef FEAT_COMMENTS
                           , &next_leader_len, &next_leader_flags, do_comments
#endif
                ))
        return TRUE;            /* "lnum" is not a paragraph line */

    if (has_format_option(FO_WHITE_PAR) && !ends_in_white(lnum - 1))
        return TRUE;            /* missing trailing space in previous line. */

    if (has_format_option(FO_Q_NUMBER) && (get_number_indent(lnum) > 0))
        return TRUE;            /* numbered item starts in "lnum". */

#ifdef FEAT_COMMENTS
    if (!same_leader(lnum - 1, leader_len, leader_flags,
                                          next_leader_len, next_leader_flags))
        return TRUE;            /* change of comment leader. */
#endif

    return FALSE;
}

#ifdef FEAT_VISUAL
/*
 * prepare a few things for block mode yank/delete/tilde
 *
 * for delete:
 * - textlen includes the first/last char to be (partly) deleted
 * - start/endspaces is the number of columns that are taken by the
 *   first/last deleted char minus the number of columns that have to be
 *   deleted.  for yank and tilde:
 * - textlen includes the first/last char to be wholly yanked
 * - start/endspaces is the number of columns of the first/last yanked char
 *   that are to be yanked.
 */
    static void
block_prep(oap, bdp, lnum, is_del)
    oparg_T             *oap;
    struct block_def    *bdp;
    linenr_T            lnum;
    int                 is_del;
{
    int         incr = 0;
    char_u      *pend;
    char_u      *pstart;
    char_u      *line;
    char_u      *prev_pstart;
    char_u      *prev_pend;

    bdp->startspaces = 0;
    bdp->endspaces = 0;
    bdp->textlen = 0;
    bdp->start_vcol = 0;
    bdp->end_vcol = 0;
#ifdef FEAT_VISUALEXTRA
    bdp->is_short = FALSE;
    bdp->is_oneChar = FALSE;
    bdp->pre_whitesp = 0;
    bdp->pre_whitesp_c = 0;
    bdp->end_char_vcols = 0;
#endif
    bdp->start_char_vcols = 0;

    line = ml_get(lnum);
    pstart = line;
    prev_pstart = line;
    while (bdp->start_vcol < oap->start_vcol && *pstart)
    {
        /* Count a tab for what it's worth (if list mode not on) */
        incr = lbr_chartabsize(pstart, (colnr_T)bdp->start_vcol);
        bdp->start_vcol += incr;
#ifdef FEAT_VISUALEXTRA
        if (vim_iswhite(*pstart))
        {
            bdp->pre_whitesp += incr;
            bdp->pre_whitesp_c++;
        }
        else
        {
            bdp->pre_whitesp = 0;
            bdp->pre_whitesp_c = 0;
        }
#endif
        prev_pstart = pstart;
        mb_ptr_adv(pstart);
    }
    bdp->start_char_vcols = incr;
    if (bdp->start_vcol < oap->start_vcol)      /* line too short */
    {
        bdp->end_vcol = bdp->start_vcol;
#ifdef FEAT_VISUALEXTRA
        bdp->is_short = TRUE;
#endif
        if (!is_del || oap->op_type == OP_APPEND)
            bdp->endspaces = oap->end_vcol - oap->start_vcol + 1;
    }
    else
    {
        /* notice: this converts partly selected Multibyte characters to
         * spaces, too. */
        bdp->startspaces = bdp->start_vcol - oap->start_vcol;
        if (is_del && bdp->startspaces)
            bdp->startspaces = bdp->start_char_vcols - bdp->startspaces;
        pend = pstart;
        bdp->end_vcol = bdp->start_vcol;
        if (bdp->end_vcol > oap->end_vcol)      /* it's all in one character */
        {
#ifdef FEAT_VISUALEXTRA
            bdp->is_oneChar = TRUE;
#endif
            if (oap->op_type == OP_INSERT)
                bdp->endspaces = bdp->start_char_vcols - bdp->startspaces;
            else if (oap->op_type == OP_APPEND)
            {
                bdp->startspaces += oap->end_vcol - oap->start_vcol + 1;
                bdp->endspaces = bdp->start_char_vcols - bdp->startspaces;
            }
            else
            {
                bdp->startspaces = oap->end_vcol - oap->start_vcol + 1;
                if (is_del && oap->op_type != OP_LSHIFT)
                {
                    /* just putting the sum of those two into
                     * bdp->startspaces doesn't work for Visual replace,
                     * so we have to split the tab in two */
                    bdp->startspaces = bdp->start_char_vcols
                                        - (bdp->start_vcol - oap->start_vcol);
                    bdp->endspaces = bdp->end_vcol - oap->end_vcol - 1;
                }
            }
        }
        else
        {
            prev_pend = pend;
            while (bdp->end_vcol <= oap->end_vcol && *pend != NUL)
            {
                /* Count a tab for what it's worth (if list mode not on) */
                prev_pend = pend;
                incr = lbr_chartabsize_adv(&pend, (colnr_T)bdp->end_vcol);
                bdp->end_vcol += incr;
            }
            if (bdp->end_vcol <= oap->end_vcol
                    && (!is_del
                        || oap->op_type == OP_APPEND
                        || oap->op_type == OP_REPLACE)) /* line too short */
            {
#ifdef FEAT_VISUALEXTRA
                bdp->is_short = TRUE;
#endif
                /* Alternative: include spaces to fill up the block.
                 * Disadvantage: can lead to trailing spaces when the line is
                 * short where the text is put */
                /* if (!is_del || oap->op_type == OP_APPEND) */
                if (oap->op_type == OP_APPEND || virtual_op)
                    bdp->endspaces = oap->end_vcol - bdp->end_vcol
                                                             + oap->inclusive;
                else
                    bdp->endspaces = 0; /* replace doesn't add characters */
            }
            else if (bdp->end_vcol > oap->end_vcol)
            {
                bdp->endspaces = bdp->end_vcol - oap->end_vcol - 1;
                if (!is_del && bdp->endspaces)
                {
                    bdp->endspaces = incr - bdp->endspaces;
                    if (pend != pstart)
                        pend = prev_pend;
                }
            }
        }
#ifdef FEAT_VISUALEXTRA
        bdp->end_char_vcols = incr;
#endif
        if (is_del && bdp->startspaces)
            pstart = prev_pstart;
        bdp->textlen = (int)(pend - pstart);
    }
    bdp->textcol = (colnr_T) (pstart - line);
    bdp->textstart = pstart;
}
#endif /* FEAT_VISUAL */

#ifdef FEAT_RIGHTLEFT
static void reverse_line __ARGS((char_u *s));

    static void
reverse_line(s)
    char_u *s;
{
    int     i, j;
    char_u  c;

    if ((i = (int)STRLEN(s) - 1) <= 0)
        return;

    curwin->w_cursor.col = i - curwin->w_cursor.col;
    for (j = 0; j < i; j++, i--)
    {
        c = s[i]; s[i] = s[j]; s[j] = c;
    }
}

# define RLADDSUBFIX(ptr) if (curwin->w_p_rl) reverse_line(ptr);
#else
# define RLADDSUBFIX(ptr)
#endif

/*
 * add or subtract 'Prenum1' from a number in a line
 * 'command' is CTRL-A for add, CTRL-X for subtract
 *
 * return FAIL for failure, OK otherwise
 */
    int
do_addsub(command, Prenum1)
    int         command;
    linenr_T    Prenum1;
{
    int         col;
    char_u      *buf1;
    char_u      buf2[NUMBUFLEN];
    int         hex;            /* 'X' or 'x': hex; '0': octal */
    static int  hexupper = FALSE;       /* 0xABC */
    unsigned long n;
    long_u      oldn;
    char_u      *ptr;
    int         c;
    int         length = 0;             /* character length of the number */
    int         todel;
    int         dohex;
    int         dooct;
    int         doalp;
    int         firstdigit;
    int         negative;
    int         subtract;

    dohex = (vim_strchr(curbuf->b_p_nf, 'x') != NULL);  /* "heX" */
    dooct = (vim_strchr(curbuf->b_p_nf, 'o') != NULL);  /* "Octal" */
    doalp = (vim_strchr(curbuf->b_p_nf, 'p') != NULL);  /* "alPha" */

    ptr = ml_get_curline();
    RLADDSUBFIX(ptr);

    /*
     * First check if we are on a hexadecimal number, after the "0x".
     */
    col = curwin->w_cursor.col;
    if (dohex)
        while (col > 0 && vim_isxdigit(ptr[col]))
            --col;
    if (       dohex
            && col > 0
            && (ptr[col] == 'X'
                || ptr[col] == 'x')
            && ptr[col - 1] == '0'
            && vim_isxdigit(ptr[col + 1]))
    {
        /*
         * Found hexadecimal number, move to its start.
         */
        --col;
    }
    else
    {
        /*
         * Search forward and then backward to find the start of number.
         */
        col = curwin->w_cursor.col;

        while (ptr[col] != NUL
                && !vim_isdigit(ptr[col])
                && !(doalp && ASCII_ISALPHA(ptr[col])))
            ++col;

        while (col > 0
                && vim_isdigit(ptr[col - 1])
                && !(doalp && ASCII_ISALPHA(ptr[col])))
            --col;
    }

    /*
     * If a number was found, and saving for undo works, replace the number.
     */
    firstdigit = ptr[col];
    RLADDSUBFIX(ptr);
    if ((!VIM_ISDIGIT(firstdigit) && !(doalp && ASCII_ISALPHA(firstdigit)))
            || u_save_cursor() != OK)
    {
        beep_flush();
        return FAIL;
    }

    /* get ptr again, because u_save() may have changed it */
    ptr = ml_get_curline();
    RLADDSUBFIX(ptr);

    if (doalp && ASCII_ISALPHA(firstdigit))
    {
        /* decrement or increment alphabetic character */
        if (command == Ctrl_X)
        {
            if (CharOrd(firstdigit) < Prenum1)
            {
                if (isupper(firstdigit))
                    firstdigit = 'A';
                else
                    firstdigit = 'a';
            }
            else
#ifdef EBCDIC
                firstdigit = EBCDIC_CHAR_ADD(firstdigit, -Prenum1);
#else
                firstdigit -= Prenum1;
#endif
        }
        else
        {
            if (26 - CharOrd(firstdigit) - 1 < Prenum1)
            {
                if (isupper(firstdigit))
                    firstdigit = 'Z';
                else
                    firstdigit = 'z';
            }
            else
#ifdef EBCDIC
                firstdigit = EBCDIC_CHAR_ADD(firstdigit, Prenum1);
#else
                firstdigit += Prenum1;
#endif
        }
        curwin->w_cursor.col = col;
        (void)del_char(FALSE);
        ins_char(firstdigit);
    }
    else
    {
        negative = FALSE;
        if (col > 0 && ptr[col - 1] == '-')         /* negative number */
        {
            --col;
            negative = TRUE;
        }

        /* get the number value (unsigned) */
        vim_str2nr(ptr + col, &hex, &length, dooct, dohex, NULL, &n);

        /* ignore leading '-' for hex and octal numbers */
        if (hex && negative)
        {
            ++col;
            --length;
            negative = FALSE;
        }

        /* add or subtract */
        subtract = FALSE;
        if (command == Ctrl_X)
            subtract ^= TRUE;
        if (negative)
            subtract ^= TRUE;

        oldn = n;
        if (subtract)
            n -= (unsigned long)Prenum1;
        else
            n += (unsigned long)Prenum1;

        /* handle wraparound for decimal numbers */
        if (!hex)
        {
            if (subtract)
            {
                if (n > oldn)
                {
                    n = 1 + (n ^ (unsigned long)-1);
                    negative ^= TRUE;
                }
            }
            else /* add */
            {
                if (n < oldn)
                {
                    n = (n ^ (unsigned long)-1);
                    negative ^= TRUE;
                }
            }
            if (n == 0)
                negative = FALSE;
        }

        /*
         * Delete the old number.
         */
        curwin->w_cursor.col = col;
        todel = length;
        c = gchar_cursor();
        /*
         * Don't include the '-' in the length, only the length of the part
         * after it is kept the same.
         */
        if (c == '-')
            --length;
        while (todel-- > 0)
        {
            if (c < 0x100 && isalpha(c))
            {
                if (isupper(c))
                    hexupper = TRUE;
                else
                    hexupper = FALSE;
            }
            /* del_char() will mark line needing displaying */
            (void)del_char(FALSE);
            c = gchar_cursor();
        }

        /*
         * Prepare the leading characters in buf1[].
         * When there are many leading zeros it could be very long.  Allocate
         * a bit too much.
         */
        buf1 = alloc((unsigned)length + NUMBUFLEN);
        if (buf1 == NULL)
            return FAIL;
        ptr = buf1;
        if (negative)
        {
            *ptr++ = '-';
        }
        if (hex)
        {
            *ptr++ = '0';
            --length;
        }
        if (hex == 'x' || hex == 'X')
        {
            *ptr++ = hex;
            --length;
        }

        /*
         * Put the number characters in buf2[].
         */
        if (hex == 0)
            sprintf((char *)buf2, "%lu", n);
        else if (hex == '0')
            sprintf((char *)buf2, "%lo", n);
        else if (hex && hexupper)
            sprintf((char *)buf2, "%lX", n);
        else
            sprintf((char *)buf2, "%lx", n);
        length -= (int)STRLEN(buf2);

        /*
         * Adjust number of zeros to the new number of digits, so the
         * total length of the number remains the same.
         * Don't do this when
         * the result may look like an octal number.
         */
        if (firstdigit == '0' && !(dooct && hex == 0))
            while (length-- > 0)
                *ptr++ = '0';
        *ptr = NUL;
        STRCAT(buf1, buf2);
        ins_str(buf1);          /* insert the new number */
        vim_free(buf1);
    }
    --curwin->w_cursor.col;
    curwin->w_set_curswant = TRUE;
#ifdef FEAT_RIGHTLEFT
    ptr = ml_get_buf(curbuf, curwin->w_cursor.lnum, TRUE);
    RLADDSUBFIX(ptr);
#endif
    return OK;
}

#ifdef FEAT_VIMINFO
    int
read_viminfo_register(virp, force)
    vir_T       *virp;
    int         force;
{
    int         eof;
    int         do_it = TRUE;
    int         size;
    int         limit;
    int         i;
    int         set_prev = FALSE;
    char_u      *str;
    char_u      **array = NULL;

    /* We only get here (hopefully) if line[0] == '"' */
    str = virp->vir_line + 1;
    if (*str == '"')
    {
        set_prev = TRUE;
        str++;
    }
    if (!ASCII_ISALNUM(*str) && *str != '-')
    {
        if (viminfo_error("E577: ", _("Illegal register name"), virp->vir_line))
            return TRUE;        /* too many errors, pretend end-of-file */
        do_it = FALSE;
    }
    get_yank_register(*str++, FALSE);
    if (!force && y_current->y_array != NULL)
        do_it = FALSE;
    size = 0;
    limit = 100;        /* Optimized for registers containing <= 100 lines */
    if (do_it)
    {
        if (set_prev)
            y_previous = y_current;
        vim_free(y_current->y_array);
        array = y_current->y_array =
                       (char_u **)alloc((unsigned)(limit * sizeof(char_u *)));
        str = skipwhite(str);
        if (STRNCMP(str, "CHAR", 4) == 0)
            y_current->y_type = MCHAR;
#ifdef FEAT_VISUAL
        else if (STRNCMP(str, "BLOCK", 5) == 0)
            y_current->y_type = MBLOCK;
#endif
        else
            y_current->y_type = MLINE;
        /* get the block width; if it's missing we get a zero, which is OK */
        str = skipwhite(skiptowhite(str));
#ifdef FEAT_VISUAL
        y_current->y_width = getdigits(&str);
#else
        (void)getdigits(&str);
#endif
    }

    while (!(eof = viminfo_readline(virp))
                    && (virp->vir_line[0] == TAB || virp->vir_line[0] == '<'))
    {
        if (do_it)
        {
            if (size >= limit)
            {
                y_current->y_array = (char_u **)
                              alloc((unsigned)(limit * 2 * sizeof(char_u *)));
                for (i = 0; i < limit; i++)
                    y_current->y_array[i] = array[i];
                vim_free(array);
                limit *= 2;
                array = y_current->y_array;
            }
            str = viminfo_readstring(virp, 1, TRUE);
            if (str != NULL)
                array[size++] = str;
            else
                do_it = FALSE;
        }
    }
    if (do_it)
    {
        if (size == 0)
        {
            vim_free(array);
            y_current->y_array = NULL;
        }
        else if (size < limit)
        {
            y_current->y_array =
                        (char_u **)alloc((unsigned)(size * sizeof(char_u *)));
            for (i = 0; i < size; i++)
                y_current->y_array[i] = array[i];
            vim_free(array);
        }
        y_current->y_size = size;
    }
    return eof;
}

    void
write_viminfo_registers(fp)
    FILE    *fp;
{
    int     i, j;
    char_u  *type;
    char_u  c;
    int     num_lines;
    int     max_num_lines;
    int     max_kbyte;
    long    len;

    fprintf(fp, _("\n# Registers:\n"));

    /* Get '<' value, use old '"' value if '<' is not found. */
    max_num_lines = get_viminfo_parameter('<');
    if (max_num_lines < 0)
        max_num_lines = get_viminfo_parameter('"');
    if (max_num_lines == 0)
        return;
    max_kbyte = get_viminfo_parameter('s');
    if (max_kbyte == 0)
        return;
    for (i = 0; i < NUM_REGISTERS; i++)
    {
        if (y_regs[i].y_array == NULL)
            continue;
#ifdef FEAT_CLIPBOARD
        /* Skip '*'/'+' register, we don't want them back next time */
        if (i == STAR_REGISTER || i == PLUS_REGISTER)
            continue;
#endif
#ifdef FEAT_DND
        /* Neither do we want the '~' register */
        if (i == TILDE_REGISTER)
            continue;
#endif
        /* Skip empty registers. */
        num_lines = y_regs[i].y_size;
        if (num_lines == 0
                || (num_lines == 1 && y_regs[i].y_type == MCHAR
                                        && STRLEN(y_regs[i].y_array[0]) == 0))
            continue;

        if (max_kbyte > 0)
        {
            /* Skip register if there is more text than the maximum size. */
            len = 0;
            for (j = 0; j < num_lines; j++)
                len += (long)STRLEN(y_regs[i].y_array[j]) + 1L;
            if (len > (long)max_kbyte * 1024L)
                continue;
        }

        switch (y_regs[i].y_type)
        {
            case MLINE:
                type = (char_u *)"LINE";
                break;
            case MCHAR:
                type = (char_u *)"CHAR";
                break;
#ifdef FEAT_VISUAL
            case MBLOCK:
                type = (char_u *)"BLOCK";
                break;
#endif
            default:
                sprintf((char *)IObuff, _("E574: Unknown register type %d"),
                                                            y_regs[i].y_type);
                emsg(IObuff);
                type = (char_u *)"LINE";
                break;
        }
        if (y_previous == &y_regs[i])
            fprintf(fp, "\"");
        c = get_register_name(i);
        fprintf(fp, "\"%c\t%s\t%d\n", c, type,
#ifdef FEAT_VISUAL
                    (int)y_regs[i].y_width
#else
                    0
#endif
                    );

        /* If max_num_lines < 0, then we save ALL the lines in the register */
        if (max_num_lines > 0 && num_lines > max_num_lines)
            num_lines = max_num_lines;
        for (j = 0; j < num_lines; j++)
        {
            putc('\t', fp);
            viminfo_writestring(fp, y_regs[i].y_array[j]);
        }
    }
}
#endif /* FEAT_VIMINFO */

#if defined(FEAT_CLIPBOARD) || defined(PROTO)
/*
 * SELECTION / PRIMARY ('*')
 *
 * Text selection stuff that uses the GUI selection register '*'.  When using a
 * GUI this may be text from another window, otherwise it is the last text we
 * had highlighted with VIsual mode.  With mouse support, clicking the middle
 * button performs the paste, otherwise you will need to do <"*p>. "
 * If not under X, it is synonymous with the clipboard register '+'.
 *
 * X CLIPBOARD ('+')
 *
 * Text selection stuff that uses the GUI clipboard register '+'.
 * Under X, this matches the standard cut/paste buffer CLIPBOARD selection.
 * It will be used for unnamed cut/pasting is 'clipboard' contains "unnamed",
 * otherwise you will need to do <"+p>. "
 * If not under X, it is synonymous with the selection register '*'.
 */

/*
 * Routine to export any final X selection we had to the environment
 * so that the text is still available after vim has exited. X selections
 * only exist while the owning application exists, so we write to the
 * permanent (while X runs) store CUT_BUFFER0.
 * Dump the CLIPBOARD selection if we own it (it's logically the more
 * 'permanent' of the two), otherwise the PRIMARY one.
 * For now, use a hard-coded sanity limit of 1Mb of data.
 */
#if defined(FEAT_X11) && defined(FEAT_CLIPBOARD)
    void
x11_export_final_selection()
{
    Display     *dpy;
    char_u      *str = NULL;
    long_u      len = 0;
    int         motion_type = -1;

# ifdef FEAT_GUI
    if (gui.in_use)
        dpy = X_DISPLAY;
    else
# endif
# ifdef FEAT_XCLIPBOARD
        dpy = xterm_dpy;
# else
        return;
# endif

    /* Get selection to export */
    if (clip_plus.owned)
        motion_type = clip_convert_selection(&str, &len, &clip_plus);
    else if (clip_star.owned)
        motion_type = clip_convert_selection(&str, &len, &clip_star);

    /* Check it's OK */
    if (dpy != NULL && str != NULL && motion_type >= 0
                                               && len < 1024*1024 && len > 0)
    {
        XStoreBuffer(dpy, (char *)str, (int)len, 0);
        XFlush(dpy);
    }

    vim_free(str);
}
#endif

    void
clip_free_selection(cbd)
    VimClipboard        *cbd;
{
    struct yankreg *y_ptr = y_current;

    if (cbd == &clip_plus)
        y_current = &y_regs[PLUS_REGISTER];
    else
        y_current = &y_regs[STAR_REGISTER];
    free_yank_all();
    y_current->y_size = 0;
    y_current = y_ptr;
}

/*
 * Get the selected text and put it in the gui selection register '*' or '+'.
 */
    void
clip_get_selection(cbd)
    VimClipboard        *cbd;
{
    struct yankreg *old_y_previous, *old_y_current;
    pos_T       old_cursor;
#ifdef FEAT_VISUAL
    pos_T       old_visual;
    int         old_visual_mode;
#endif
    colnr_T     old_curswant;
    int         old_set_curswant;
    pos_T       old_op_start, old_op_end;
    oparg_T     oa;
    cmdarg_T    ca;

    if (cbd->owned)
    {
        if ((cbd == &clip_plus && y_regs[PLUS_REGISTER].y_array != NULL)
                || (cbd == &clip_star && y_regs[STAR_REGISTER].y_array != NULL))
            return;

        /* Get the text between clip_star.start & clip_star.end */
        old_y_previous = y_previous;
        old_y_current = y_current;
        old_cursor = curwin->w_cursor;
        old_curswant = curwin->w_curswant;
        old_set_curswant = curwin->w_set_curswant;
        old_op_start = curbuf->b_op_start;
        old_op_end = curbuf->b_op_end;
#ifdef FEAT_VISUAL
        old_visual = VIsual;
        old_visual_mode = VIsual_mode;
#endif
        clear_oparg(&oa);
        oa.regname = (cbd == &clip_plus ? '+' : '*');
        oa.op_type = OP_YANK;
        vim_memset(&ca, 0, sizeof(ca));
        ca.oap = &oa;
        ca.cmdchar = 'y';
        ca.count1 = 1;
        ca.retval = CA_NO_ADJ_OP_END;
        do_pending_operator(&ca, 0, TRUE);
        y_previous = old_y_previous;
        y_current = old_y_current;
        curwin->w_cursor = old_cursor;
        changed_cline_bef_curs();   /* need to update w_virtcol et al */
        curwin->w_curswant = old_curswant;
        curwin->w_set_curswant = old_set_curswant;
        curbuf->b_op_start = old_op_start;
        curbuf->b_op_end = old_op_end;
#ifdef FEAT_VISUAL
        VIsual = old_visual;
        VIsual_mode = old_visual_mode;
#endif
    }
    else
    {
        clip_free_selection(cbd);

        /* Try to get selected text from another window */
        clip_gen_request_selection(cbd);
    }
}

/* Convert from the GUI selection string into the '*'/'+' register */
    void
clip_yank_selection(type, str, len, cbd)
    int         type;
    char_u      *str;
    long        len;
    VimClipboard *cbd;
{
    struct yankreg *y_ptr;

    if (cbd == &clip_plus)
        y_ptr = &y_regs[PLUS_REGISTER];
    else
        y_ptr = &y_regs[STAR_REGISTER];

    clip_free_selection(cbd);

    str_to_reg(y_ptr, type, str, len, 0L);
}

/*
 * Convert the '*'/'+' register into a GUI selection string returned in *str
 * with length *len.
 * Returns the motion type, or -1 for failure.
 */
    int
clip_convert_selection(str, len, cbd)
    char_u      **str;
    long_u      *len;
    VimClipboard *cbd;
{
    char_u      *p;
    int         lnum;
    int         i, j;
    int_u       eolsize;
    struct yankreg *y_ptr;

    if (cbd == &clip_plus)
        y_ptr = &y_regs[PLUS_REGISTER];
    else
        y_ptr = &y_regs[STAR_REGISTER];

#ifdef USE_CRNL
    eolsize = 2;
#else
    eolsize = 1;
#endif

    *str = NULL;
    *len = 0;
    if (y_ptr->y_array == NULL)
        return -1;

    for (i = 0; i < y_ptr->y_size; i++)
        *len += (long_u)STRLEN(y_ptr->y_array[i]) + eolsize;

    /*
     * Don't want newline character at end of last line if we're in MCHAR mode.
     */
    if (y_ptr->y_type == MCHAR && *len >= eolsize)
        *len -= eolsize;

    p = *str = lalloc(*len + 1, TRUE);  /* add one to avoid zero */
    if (p == NULL)
        return -1;
    lnum = 0;
    for (i = 0, j = 0; i < (int)*len; i++, j++)
    {
        if (y_ptr->y_array[lnum][j] == '\n')
            p[i] = NUL;
        else if (y_ptr->y_array[lnum][j] == NUL)
        {
#ifdef USE_CRNL
            p[i++] = '\r';
#endif
#ifdef USE_CR
            p[i] = '\r';
#else
            p[i] = '\n';
#endif
            lnum++;
            j = -1;
        }
        else
            p[i] = y_ptr->y_array[lnum][j];
    }
    return y_ptr->y_type;
}


# if defined(FEAT_VISUAL) || defined(FEAT_EVAL)
/*
 * If we have written to a clipboard register, send the text to the clipboard.
 */
    static void
may_set_selection()
{
    if (y_current == &(y_regs[STAR_REGISTER]) && clip_star.available)
    {
        clip_own_selection(&clip_star);
        clip_gen_set_selection(&clip_star);
    }
    else if (y_current == &(y_regs[PLUS_REGISTER]) && clip_plus.available)
    {
        clip_own_selection(&clip_plus);
        clip_gen_set_selection(&clip_plus);
    }
}
# endif

#endif /* FEAT_CLIPBOARD || PROTO */


#if defined(FEAT_DND) || defined(PROTO)
/*
 * Replace the contents of the '~' register with str.
 */
    void
dnd_yank_drag_data(str, len)
    char_u      *str;
    long        len;
{
    struct yankreg *curr;

    curr = y_current;
    y_current = &y_regs[TILDE_REGISTER];
    free_yank_all();
    str_to_reg(y_current, MCHAR, str, len, 0L);
    y_current = curr;
}
#endif


#if defined(FEAT_EVAL) || defined(PROTO)
/*
 * Return the type of a register.
 * Used for getregtype()
 * Returns MAUTO for error.
 */
    char_u
get_reg_type(regname, reglen)
    int     regname;
    long    *reglen;
{
    switch (regname)
    {
        case '%':               /* file name */
        case '#':               /* alternate file name */
        case '=':               /* expression */
        case ':':               /* last command line */
        case '/':               /* last search-pattern */
        case '.':               /* last inserted text */
#ifdef FEAT_SEARCHPATH
        case Ctrl_F:            /* Filename under cursor */
        case Ctrl_P:            /* Path under cursor, expand via "path" */
#endif
        case Ctrl_W:            /* word under cursor */
        case Ctrl_A:            /* WORD (mnemonic All) under cursor */
        case '_':               /* black hole: always empty */
            return MCHAR;
    }

#ifdef FEAT_CLIPBOARD
    regname = may_get_selection(regname);
#endif

    /* Should we check for a valid name? */
    get_yank_register(regname, FALSE);

    if (y_current->y_array != NULL)
    {
#ifdef FEAT_VISUAL
        if (reglen != NULL && y_current->y_type == MBLOCK)
            *reglen = y_current->y_width;
#endif
        return y_current->y_type;
    }
    return MAUTO;
}

/*
 * Return the contents of a register as a single allocated string.
 * Used for "@r" in expressions and for getreg().
 * Returns NULL for error.
 */
    char_u *
get_reg_contents(regname, allowexpr, expr_src)
    int         regname;
    int         allowexpr;      /* allow "=" register */
    int         expr_src;       /* get expression for "=" register */
{
    long        i;
    char_u      *retval;
    int         allocated;
    long        len;

    /* Don't allow using an expression register inside an expression */
    if (regname == '=')
    {
        if (allowexpr)
        {
            if (expr_src)
                return get_expr_line_src();
            return get_expr_line();
        }
        return NULL;
    }

    if (regname == '@')     /* "@@" is used for unnamed register */
        regname = '"';

    /* check for valid regname */
    if (regname != NUL && !valid_yank_reg(regname, FALSE))
        return NULL;

#ifdef FEAT_CLIPBOARD
    regname = may_get_selection(regname);
#endif

    if (get_spec_reg(regname, &retval, &allocated, FALSE))
    {
        if (retval == NULL)
            return NULL;
        if (!allocated)
            retval = vim_strsave(retval);
        return retval;
    }

    get_yank_register(regname, FALSE);
    if (y_current->y_array == NULL)
        return NULL;

    /*
     * Compute length of resulting string.
     */
    len = 0;
    for (i = 0; i < y_current->y_size; ++i)
    {
        len += (long)STRLEN(y_current->y_array[i]);
        /*
         * Insert a newline between lines and after last line if
         * y_type is MLINE.
         */
        if (y_current->y_type == MLINE || i < y_current->y_size - 1)
            ++len;
    }

    retval = lalloc(len + 1, TRUE);

    /*
     * Copy the lines of the yank register into the string.
     */
    if (retval != NULL)
    {
        len = 0;
        for (i = 0; i < y_current->y_size; ++i)
        {
            STRCPY(retval + len, y_current->y_array[i]);
            len += (long)STRLEN(retval + len);

            /*
             * Insert a NL between lines and after the last line if y_type is
             * MLINE.
             */
            if (y_current->y_type == MLINE || i < y_current->y_size - 1)
                retval[len++] = '\n';
        }
        retval[len] = NUL;
    }

    return retval;
}

/*
 * Store string "str" in register "name".
 * "maxlen" is the maximum number of bytes to use, -1 for all bytes.
 * If "must_append" is TRUE, always append to the register.  Otherwise append
 * if "name" is an uppercase letter.
 * Note: "maxlen" and "must_append" don't work for the "/" register.
 * Careful: 'str' is modified, you may have to use a copy!
 * If "str" ends in '\n' or '\r', use linewise, otherwise use characterwise.
 */
    void
write_reg_contents(name, str, maxlen, must_append)
    int         name;
    char_u      *str;
    int         maxlen;
    int         must_append;
{
    write_reg_contents_ex(name, str, maxlen, must_append, MAUTO, 0L);
}

    void
write_reg_contents_ex(name, str, maxlen, must_append, yank_type, block_len)
    int         name;
    char_u      *str;
    int         maxlen;
    int         must_append;
    int         yank_type;
    long        block_len;
{
    struct yankreg  *old_y_previous, *old_y_current;
    long            len;

    if (maxlen >= 0)
        len = maxlen;
    else
        len = (long)STRLEN(str);

    /* Special case: '/' search pattern */
    if (name == '/')
    {
        set_last_search_pat(str, RE_SEARCH, TRUE, TRUE);
        return;
    }

#ifdef FEAT_EVAL
    if (name == '=')
    {
        char_u      *p, *s;

        p = vim_strnsave(str, (int)len);
        if (p == NULL)
            return;
        if (must_append)
        {
            s = concat_str(get_expr_line_src(), p);
            vim_free(p);
            p = s;

        }
        set_expr_line(p);
        return;
    }
#endif

    if (!valid_yank_reg(name, TRUE))        /* check for valid reg name */
    {
        emsg_invreg(name);
        return;
    }

    if (name == '_')        /* black hole: nothing to do */
        return;

    /* Don't want to change the current (unnamed) register */
    old_y_previous = y_previous;
    old_y_current = y_current;

    get_yank_register(name, TRUE);
    if (!y_append && !must_append)
        free_yank_all();
#ifndef FEAT_VISUAL
    /* Just in case - make sure we don't use MBLOCK */
    if (yank_type == MBLOCK)
        yank_type = MAUTO;
#endif
    if (yank_type == MAUTO)
        yank_type = ((len > 0 && (str[len - 1] == '\n' || str[len - 1] == '\r'))
                                                             ? MLINE : MCHAR);
    str_to_reg(y_current, yank_type, str, len, block_len);

# ifdef FEAT_CLIPBOARD
    /* Send text of clipboard register to the clipboard. */
    may_set_selection();
# endif

    /* ':let @" = "val"' should change the meaning of the "" register */
    if (name != '"')
        y_previous = old_y_previous;
    y_current = old_y_current;
}
#endif  /* FEAT_EVAL */

#if defined(FEAT_CLIPBOARD) || defined(FEAT_EVAL)
/*
 * Put a string into a register.  When the register is not empty, the string
 * is appended.
 */
    static void
str_to_reg(y_ptr, type, str, len, blocklen)
    struct yankreg      *y_ptr;         /* pointer to yank register */
    int                 type;           /* MCHAR, MLINE or MBLOCK */
    char_u              *str;           /* string to put in register */
    long                len;            /* length of string */
    long                blocklen;       /* width of Visual block */
{
    int         lnum;
    long        start;
    long        i;
    int         extra;
    int         newlines;               /* number of lines added */
    int         extraline = 0;          /* extra line at the end */
    int         append = FALSE;         /* append to last line in register */
    char_u      *s;
    char_u      **pp;
#ifdef FEAT_VISUAL
    long        maxlen;
#endif

    if (y_ptr->y_array == NULL)         /* NULL means emtpy register */
        y_ptr->y_size = 0;

    /*
     * Count the number of lines within the string
     */
    newlines = 0;
    for (i = 0; i < len; i++)
        if (str[i] == '\n')
            ++newlines;
    if (type == MCHAR || len == 0 || str[len - 1] != '\n')
    {
        extraline = 1;
        ++newlines;     /* count extra newline at the end */
    }
    if (y_ptr->y_size > 0 && y_ptr->y_type == MCHAR)
    {
        append = TRUE;
        --newlines;     /* uncount newline when appending first line */
    }

    /*
     * Allocate an array to hold the pointers to the new register lines.
     * If the register was not empty, move the existing lines to the new array.
     */
    pp = (char_u **)lalloc_clear((y_ptr->y_size + newlines)
                                                    * sizeof(char_u *), TRUE);
    if (pp == NULL)     /* out of memory */
        return;
    for (lnum = 0; lnum < y_ptr->y_size; ++lnum)
        pp[lnum] = y_ptr->y_array[lnum];
    vim_free(y_ptr->y_array);
    y_ptr->y_array = pp;
#ifdef FEAT_VISUAL
    maxlen = 0;
#endif

    /*
     * Find the end of each line and save it into the array.
     */
    for (start = 0; start < len + extraline; start += i + 1)
    {
        for (i = start; i < len; ++i)   /* find the end of the line */
            if (str[i] == '\n')
                break;
        i -= start;                     /* i is now length of line */
#ifdef FEAT_VISUAL
        if (i > maxlen)
            maxlen = i;
#endif
        if (append)
        {
            --lnum;
            extra = (int)STRLEN(y_ptr->y_array[lnum]);
        }
        else
            extra = 0;
        s = alloc((unsigned)(i + extra + 1));
        if (s == NULL)
            break;
        if (extra)
            mch_memmove(s, y_ptr->y_array[lnum], (size_t)extra);
        if (append)
            vim_free(y_ptr->y_array[lnum]);
        if (i)
            mch_memmove(s + extra, str + start, (size_t)i);
        extra += i;
        s[extra] = NUL;
        y_ptr->y_array[lnum++] = s;
        while (--extra >= 0)
        {
            if (*s == NUL)
                *s = '\n';          /* replace NUL with newline */
            ++s;
        }
        append = FALSE;             /* only first line is appended */
    }
    y_ptr->y_type = type;
    y_ptr->y_size = lnum;
# ifdef FEAT_VISUAL
    if (type == MBLOCK)
        y_ptr->y_width = (blocklen < 0 ? maxlen - 1 : blocklen);
    else
        y_ptr->y_width = 0;
# endif
}
#endif /* FEAT_CLIPBOARD || FEAT_EVAL || PROTO */

    void
clear_oparg(oap)
    oparg_T     *oap;
{
    vim_memset(oap, 0, sizeof(oparg_T));
}

static long     line_count_info __ARGS((char_u *line, long *wc, long *cc, long limit, int eol_size));

/*
 *  Count the number of bytes, characters and "words" in a line.
 *
 *  "Words" are counted by looking for boundaries between non-space and
 *  space characters.  (it seems to produce results that match 'wc'.)
 *
 *  Return value is byte count; word count for the line is added to "*wc".
 *  Char count is added to "*cc".
 *
 *  The function will only examine the first "limit" characters in the
 *  line, stopping if it encounters an end-of-line (NUL byte).  In that
 *  case, eol_size will be added to the character count to account for
 *  the size of the EOL character.
 */
    static long
line_count_info(line, wc, cc, limit, eol_size)
    char_u      *line;
    long        *wc;
    long        *cc;
    long        limit;
    int         eol_size;
{
    long        i;
    long        words = 0;
    long        chars = 0;
    int         is_word = 0;

    for (i = 0; line[i] && i < limit; )
    {
        if (is_word)
        {
            if (vim_isspace(line[i]))
            {
                words++;
                is_word = 0;
            }
        }
        else if (!vim_isspace(line[i]))
            is_word = 1;
        ++chars;
#ifdef FEAT_MBYTE
        i += (*mb_ptr2len)(line + i);
#else
        ++i;
#endif
    }

    if (is_word)
        words++;
    *wc += words;

    /* Add eol_size if the end of line was reached before hitting limit. */
    if (line[i] == NUL && i < limit)
    {
        i += eol_size;
        chars += eol_size;
    }
    *cc += chars;
    return i;
}

/*
 * Give some info about the position of the cursor (for "g CTRL-G").
 * In Visual mode, give some info about the selected region.  (In this case,
 * the *_count_cursor variables store running totals for the selection.)
 */
    void
cursor_pos_info()
{
    char_u      *p;
    char_u      buf1[50];
    char_u      buf2[40];
    linenr_T    lnum;
    long        byte_count = 0;
    long        byte_count_cursor = 0;
    long        char_count = 0;
    long        char_count_cursor = 0;
    long        word_count = 0;
    long        word_count_cursor = 0;
    int         eol_size;
    long        last_check = 100000L;
#ifdef FEAT_VISUAL
    long        line_count_selected = 0;
    pos_T       min_pos, max_pos;
    oparg_T     oparg;
    struct block_def    bd;
#endif

    /*
     * Compute the length of the file in characters.
     */
    if (curbuf->b_ml.ml_flags & ML_EMPTY)
    {
        MSG(_(no_lines_msg));
    }
    else
    {
        if (get_fileformat(curbuf) == EOL_DOS)
            eol_size = 2;
        else
            eol_size = 1;

#ifdef FEAT_VISUAL
        if (VIsual_active)
        {
            if (lt(VIsual, curwin->w_cursor))
            {
                min_pos = VIsual;
                max_pos = curwin->w_cursor;
            }
            else
            {
                min_pos = curwin->w_cursor;
                max_pos = VIsual;
            }
            if (*p_sel == 'e' && max_pos.col > 0)
                --max_pos.col;

            if (VIsual_mode == Ctrl_V)
            {
                oparg.is_VIsual = 1;
                oparg.block_mode = TRUE;
                oparg.op_type = OP_NOP;
                getvcols(curwin, &min_pos, &max_pos,
                                          &oparg.start_vcol, &oparg.end_vcol);
                if (curwin->w_curswant == MAXCOL)
                    oparg.end_vcol = MAXCOL;
                /* Swap the start, end vcol if needed */
                if (oparg.end_vcol < oparg.start_vcol)
                {
                    oparg.end_vcol += oparg.start_vcol;
                    oparg.start_vcol = oparg.end_vcol - oparg.start_vcol;
                    oparg.end_vcol -= oparg.start_vcol;
                }
            }
            line_count_selected = max_pos.lnum - min_pos.lnum + 1;
        }
#endif

        for (lnum = 1; lnum <= curbuf->b_ml.ml_line_count; ++lnum)
        {
            /* Check for a CTRL-C every 100000 characters. */
            if (byte_count > last_check)
            {
                ui_breakcheck();
                if (got_int)
                    return;
                last_check = byte_count + 100000L;
            }

#ifdef FEAT_VISUAL
            /* Do extra processing for VIsual mode. */
            if (VIsual_active
                    && lnum >= min_pos.lnum && lnum <= max_pos.lnum)
            {
                char_u      *s = NULL;
                long        len = 0L;

                switch (VIsual_mode)
                {
                    case Ctrl_V:
# ifdef FEAT_VIRTUALEDIT
                        virtual_op = virtual_active();
# endif
                        block_prep(&oparg, &bd, lnum, 0);
# ifdef FEAT_VIRTUALEDIT
                        virtual_op = MAYBE;
# endif
                        s = bd.textstart;
                        len = (long)bd.textlen;
                        break;
                    case 'V':
                        s = ml_get(lnum);
                        len = MAXCOL;
                        break;
                    case 'v':
                        {
                            colnr_T start_col = (lnum == min_pos.lnum)
                                                           ? min_pos.col : 0;
                            colnr_T end_col = (lnum == max_pos.lnum)
                                      ? max_pos.col - start_col + 1 : MAXCOL;

                            s = ml_get(lnum) + start_col;
                            len = end_col;
                        }
                        break;
                }
                if (s != NULL)
                {
                    byte_count_cursor += line_count_info(s, &word_count_cursor,
                                           &char_count_cursor, len, eol_size);
                    if (lnum == curbuf->b_ml.ml_line_count
                            && !curbuf->b_p_eol
                            && curbuf->b_p_bin
                            && (long)STRLEN(s) < len)
                        byte_count_cursor -= eol_size;
                }
            }
            else
#endif
            {
                /* In non-visual mode, check for the line the cursor is on */
                if (lnum == curwin->w_cursor.lnum)
                {
                    word_count_cursor += word_count;
                    char_count_cursor += char_count;
                    byte_count_cursor = byte_count +
                        line_count_info(ml_get(lnum),
                                &word_count_cursor, &char_count_cursor,
                                  (long)(curwin->w_cursor.col + 1), eol_size);
                }
            }
            /* Add to the running totals */
            byte_count += line_count_info(ml_get(lnum), &word_count,
                                         &char_count, (long)MAXCOL, eol_size);
        }

        /* Correction for when last line doesn't have an EOL. */
        if (!curbuf->b_p_eol && curbuf->b_p_bin)
            byte_count -= eol_size;

#ifdef FEAT_VISUAL
        if (VIsual_active)
        {
            if (VIsual_mode == Ctrl_V && curwin->w_curswant < MAXCOL)
            {
                getvcols(curwin, &min_pos, &max_pos, &min_pos.col,
                                                                &max_pos.col);
                sprintf((char *)buf1, _("%ld Cols; "),
                        (long)(oparg.end_vcol - oparg.start_vcol + 1));
            }
            else
                buf1[0] = NUL;

            if (char_count_cursor == byte_count_cursor
                                                  && char_count == byte_count)
                sprintf((char *)IObuff, _("Selected %s%ld of %ld Lines; %ld of %ld Words; %ld of %ld Bytes"),
                        buf1, line_count_selected,
                        (long)curbuf->b_ml.ml_line_count,
                        word_count_cursor, word_count,
                        byte_count_cursor, byte_count);
            else
                sprintf((char *)IObuff, _("Selected %s%ld of %ld Lines; %ld of %ld Words; %ld of %ld Chars; %ld of %ld Bytes"),
                        buf1, line_count_selected,
                        (long)curbuf->b_ml.ml_line_count,
                        word_count_cursor, word_count,
                        char_count_cursor, char_count,
                        byte_count_cursor, byte_count);
        }
        else
#endif
        {
            p = ml_get_curline();
            validate_virtcol();
            col_print(buf1, (int)curwin->w_cursor.col + 1,
                    (int)curwin->w_virtcol + 1);
            col_print(buf2, (int)STRLEN(p), linetabsize(p));

            if (char_count_cursor == byte_count_cursor
                    && char_count == byte_count)
                sprintf((char *)IObuff, _("Col %s of %s; Line %ld of %ld; Word %ld of %ld; Byte %ld of %ld"),
                    (char *)buf1, (char *)buf2,
                    (long)curwin->w_cursor.lnum,
                    (long)curbuf->b_ml.ml_line_count,
                    word_count_cursor, word_count,
                    byte_count_cursor, byte_count);
            else
                sprintf((char *)IObuff, _("Col %s of %s; Line %ld of %ld; Word %ld of %ld; Char %ld of %ld; Byte %ld of %ld"),
                    (char *)buf1, (char *)buf2,
                    (long)curwin->w_cursor.lnum,
                    (long)curbuf->b_ml.ml_line_count,
                    word_count_cursor, word_count,
                    char_count_cursor, char_count,
                    byte_count_cursor, byte_count);
        }

#ifdef FEAT_MBYTE
        byte_count = bomb_size();
        if (byte_count > 0)
            sprintf((char *)IObuff + STRLEN(IObuff), _("(+%ld for BOM)"),
                                                                  byte_count);
#endif
        /* Don't shorten this message, the user asked for it. */
        p = p_shm;
        p_shm = (char_u *)"";
        msg(IObuff);
        p_shm = p;
    }
}