("" < 3.4) always evaluates to true, which unconditionally

[dragonfly.git] / contrib / less-381 / output.c

/*
 * Copyright (C) 1984-2002  Mark Nudelman
 *
 * You may distribute under the terms of either the GNU General Public
 * License or the Less License, as specified in the README file.
 *
 * For more information about less, or for information on how to 
 * contact the author, see the README file.
 */


/*
 * High level routines dealing with the output to the screen.
 */

#include "less.h"
#if MSDOS_COMPILER==WIN32C
#include "windows.h"
#endif

public int errmsgs;     /* Count of messages displayed by error() */
public int need_clr;
public int final_attr;

extern int sigs;
extern int sc_width;
extern int so_s_width, so_e_width;
extern int screen_trashed;
extern int any_display;
extern int is_tty;

#if MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
extern int ctldisp;
extern int nm_fg_color, nm_bg_color;
extern int bo_fg_color, bo_bg_color;
extern int ul_fg_color, ul_bg_color;
extern int so_fg_color, so_bg_color;
extern int bl_fg_color, bl_bg_color;
#endif

/*
 * Display the line which is in the line buffer.
 */
        public void
put_line()
{
        register int c;
        register int i;
        int a;
        int curr_attr;

        if (ABORT_SIGS())
        {
                /*
                 * Don't output if a signal is pending.
                 */
                screen_trashed = 1;
                return;
        }

        curr_attr = AT_NORMAL;

        for (i = 0;  (c = gline(i, &a)) != '\0';  i++)
        {
                if (a != curr_attr)
                {
                        /*
                         * Changing attributes.
                         * Display the exit sequence for the old attribute
                         * and the enter sequence for the new one.
                         */
                        switch (curr_attr)
                        {
                        case AT_UNDERLINE:      ul_exit();      break;
                        case AT_BOLD:           bo_exit();      break;
                        case AT_BLINK:          bl_exit();      break;
                        case AT_STANDOUT:       so_exit();      break;
                        }
                        switch (a)
                        {
                        case AT_UNDERLINE:      ul_enter();     break;
                        case AT_BOLD:           bo_enter();     break;
                        case AT_BLINK:          bl_enter();     break;
                        case AT_STANDOUT:       so_enter();     break;
                        }
                        curr_attr = a;
                }
                if (curr_attr == AT_INVIS)
                        continue;
                if (c == '\b')
                        putbs();
                else
                        putchr(c);
        }

        switch (curr_attr)
        {
        case AT_UNDERLINE:      ul_exit();      break;
        case AT_BOLD:           bo_exit();      break;
        case AT_BLINK:          bl_exit();      break;
        case AT_STANDOUT:       so_exit();      break;
        }
        final_attr = curr_attr;
}

static char obuf[OUTBUF_SIZE];
static char *ob = obuf;

/*
 * Flush buffered output.
 *
 * If we haven't displayed any file data yet,
 * output messages on error output (file descriptor 2),
 * otherwise output on standard output (file descriptor 1).
 *
 * This has the desirable effect of producing all
 * error messages on error output if standard output
 * is directed to a file.  It also does the same if
 * we never produce any real output; for example, if
 * the input file(s) cannot be opened.  If we do
 * eventually produce output, code in edit() makes
 * sure these messages can be seen before they are
 * overwritten or scrolled away.
 */
        public void
flush()
{
        register int n;
        register int fd;

        n = ob - obuf;
        if (n == 0)
                return;
#if MSDOS_COMPILER==WIN32C
        if (is_tty && any_display)
        {
                char *op;
                DWORD nwritten = 0;
                CONSOLE_SCREEN_BUFFER_INFO scr;
                int row;
                int col;
                int olen;
                extern HANDLE con_out;

                olen = ob - obuf;
                /*
                 * There is a bug in Win32 WriteConsole() if we're
                 * writing in the last cell with a different color.
                 * To avoid color problems in the bottom line,
                 * we scroll the screen manually, before writing.
                 */
                GetConsoleScreenBufferInfo(con_out, &scr);
                col = scr.dwCursorPosition.X;
                row = scr.dwCursorPosition.Y;
                for (op = obuf;  op < obuf + olen;  op++)
                {
                        if (*op == '\n')
                        {
                                col = 0;
                                row++;
                        } else if (*op == '\r')
                        {
                                col = 0;
                        } else
                        {
                                col++;
                                if (col >= sc_width)
                                {
                                        col = 0;
                                        row++;
                                }
                        }
                }
                if (row > scr.srWindow.Bottom)
                        win32_scroll_up(row - scr.srWindow.Bottom);
                WriteConsole(con_out, obuf, olen, &nwritten, NULL);
                ob = obuf;
                return;
        }
#else
#if MSDOS_COMPILER==MSOFTC
        if (is_tty && any_display)
        {
                *ob = '\0';
                _outtext(obuf);
                ob = obuf;
                return;
        }
#else
#if MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
        if (is_tty && any_display)
        {
                *ob = '\0';
                if (ctldisp != OPT_ONPLUS)
                        cputs(obuf);
                else
                {
                        /*
                         * Look for SGR escape sequences, and convert them
                         * to color commands.  Replace bold, underline,
                         * and italic escapes into colors specified via
                         * the -D command-line option.
                         */
                        char *anchor, *p, *p_next;
                        int buflen = ob - obuf;
                        unsigned char fg, bg, norm_attr;
                        /*
                         * Only dark colors mentioned here, so that
                         * bold has visible effect.
                         */
                        static enum COLORS screen_color[] = {
                                BLACK, RED, GREEN, BROWN,
                                BLUE, MAGENTA, CYAN, LIGHTGRAY
                        };

                        /* Normal text colors are used as baseline. */
                        bg = nm_bg_color & 0xf;
                        fg = nm_fg_color & 0xf;
                        norm_attr = (bg << 4) | fg;
                        for (anchor = p_next = obuf;
                             (p_next = memchr (p_next, ESC,
                                               buflen - (p_next - obuf)))
                               != NULL; )
                        {
                                p = p_next;

                                /*
                                 * Handle the null escape sequence
                                 * (ESC-[m), which is used to restore
                                 * the original color.
                                 */
                                if (p[1] == '[' && is_ansi_end(p[2]))
                                {
                                        textattr(norm_attr);
                                        p += 3;
                                        anchor = p_next = p;
                                        continue;
                                }

                                if (p[1] == '[')        /* "Esc-[" sequence */
                                {
                                        /*
                                         * If some chars seen since
                                         * the last escape sequence,
                                         * write it out to the screen
                                         * using current text attributes.
                                         */
                                        if (p > anchor)
                                        {
                                                *p = '\0';
                                                cputs (anchor);
                                                *p = ESC;
                                                anchor = p;
                                        }
                                        p += 2;
                                        p_next = p;
                                        while (!is_ansi_end(*p))
                                        {
                                                char *q;
                                                long code = strtol(p, &q, 10);

                                                if (!*q)
                                                {
                                                        /*
                                                         * Incomplete sequence.
                                                         * Leave it unprocessed
                                                         * in the buffer.
                                                         */
                                                        int slop = q - anchor;
                                                        strcpy(obuf, anchor);
                                                        ob = &obuf[slop];
                                                        return;
                                                }

                                                if (q == p
                                                    || code > 49 || code < 0
                                                    || (!is_ansi_end(*q)
                                                        && *q != ';'))
                                                {
                                                        p_next = q;
                                                        break;
                                                }
                                                if (*q == ';')
                                                        q++;

                                                switch (code)
                                                {
                                                case 1: /* bold on */
                                                        fg = bo_fg_color;
                                                        bg = bo_bg_color;
                                                        break;
                                                case 3: /* italic on */
                                                        fg = so_fg_color;
                                                        bg = so_bg_color;
                                                        break;
                                                case 4: /* underline on */
                                                        fg = ul_fg_color;
                                                        bg = ul_bg_color;
                                                        break;
                                                case 8: /* concealed on */
                                                        fg = (bg & 7) | 8;
                                                        break;
                                                case 0: /* all attrs off */
                                                case 22:/* bold off */
                                                case 23:/* italic off */
                                                case 24:/* underline off */
                                                        fg = nm_fg_color;
                                                        bg = nm_bg_color;
                                                        break;
                                                case 30: case 31: case 32:
                                                case 33: case 34: case 35:
                                                case 36: case 37:
                                                        fg = (fg & 8) | (screen_color[code - 30]);
                                                        break;
                                                case 39: /* default fg */
                                                        fg = nm_fg_color;
                                                        break;
                                                case 40: case 41: case 42:
                                                case 43: case 44: case 45:
                                                case 46: case 47:
                                                        bg = (bg & 8) | (screen_color[code - 40]);
                                                        break;
                                                case 49: /* default fg */
                                                        bg = nm_bg_color;
                                                        break;
                                                }
                                                p = q;
                                        }
                                        if (is_ansi_end(*p) && p > p_next)
                                        {
                                                bg &= 15;
                                                fg &= 15;
                                                textattr ((bg << 4)| fg);
                                                p_next = anchor = p + 1;
                                        } else
                                                break;
                                } else
                                        p_next++;
                        }

                        /* Output what's left in the buffer.  */
                        cputs (anchor);
                }
                ob = obuf;
                return;
        }
#endif
#endif
#endif
        fd = (any_display) ? 1 : 2;
        if (write(fd, obuf, n) != n)
                screen_trashed = 1;
        ob = obuf;
}

/*
 * Output a character.
 */
        public int
putchr(c)
        int c;
{
        if (need_clr)
        {
                need_clr = 0;
                clear_bot();
        }
#if MSDOS_COMPILER
        if (c == '\n' && is_tty)
        {
                /* remove_top(1); */
                putchr('\r');
        }
#else
#ifdef _OSK
        if (c == '\n' && is_tty)  /* In OS-9, '\n' == 0x0D */
                putchr(0x0A);
#endif
#endif
        /*
         * Some versions of flush() write to *ob, so we must flush
         * when we are still one char from the end of obuf.
         */
        if (ob >= &obuf[sizeof(obuf)-1])
                flush();
        *ob++ = c;
        return (c);
}

/*
 * Output a string.
 */
        public void
putstr(s)
        register char *s;
{
        while (*s != '\0')
                putchr(*s++);
}


/*
 * Convert an integral type to a string.
 */
#define TYPE_TO_A_FUNC(funcname, type) \
void funcname(num, buf) \
        type num; \
        char *buf; \
{ \
        int neg = (num < 0); \
        char tbuf[INT_STRLEN_BOUND(num)+2]; \
        register char *s = tbuf + sizeof(tbuf); \
        if (neg) num = -num; \
        *--s = '\0'; \
        do { \
                *--s = (num % 10) + '0'; \
        } while ((num /= 10) != 0); \
        if (neg) *--s = '-'; \
        strcpy(buf, s); \
}

TYPE_TO_A_FUNC(postoa, POSITION)
TYPE_TO_A_FUNC(linenumtoa, LINENUM)
TYPE_TO_A_FUNC(inttoa, int)

/*
 * Output an integer in a given radix.
 */
        static int
iprint_int(num)
        int num;
{
        char buf[INT_STRLEN_BOUND(num)];

        inttoa(num, buf);
        putstr(buf);
        return (strlen(buf));
}

/*
 * Output a line number in a given radix.
 */
        static int
iprint_linenum(num)
        LINENUM num;
{
        char buf[INT_STRLEN_BOUND(num)];

        linenumtoa(num, buf);
        putstr(buf);
        return (strlen(buf));
}

/*
 * This function implements printf-like functionality
 * using a more portable argument list mechanism than printf's.
 */
        static int
less_printf(fmt, parg)
        register char *fmt;
        PARG *parg;
{
        register char *s;
        register int col;

        col = 0;
        while (*fmt != '\0')
        {
                if (*fmt != '%')
                {
                        putchr(*fmt++);
                        col++;
                } else
                {
                        ++fmt;
                        switch (*fmt++)
                        {
                        case 's':
                                s = parg->p_string;
                                parg++;
                                while (*s != '\0')
                                {
                                        putchr(*s++);
                                        col++;
                                }
                                break;
                        case 'd':
                                col += iprint_int(parg->p_int);
                                parg++;
                                break;
                        case 'n':
                                col += iprint_linenum(parg->p_linenum);
                                parg++;
                                break;
                        }
                }
        }
        return (col);
}

/*
 * Get a RETURN.
 * If some other non-trivial char is pressed, unget it, so it will
 * become the next command.
 */
        public void
get_return()
{
        int c;

#if ONLY_RETURN
        while ((c = getchr()) != '\n' && c != '\r')
                bell();
#else
        c = getchr();
        if (c != '\n' && c != '\r' && c != ' ' && c != READ_INTR)
                ungetcc(c);
#endif
}

/*
 * Output a message in the lower left corner of the screen
 * and wait for carriage return.
 */
        public void
error(fmt, parg)
        char *fmt;
        PARG *parg;
{
        int col = 0;
        static char return_to_continue[] = "  (press RETURN)";

        errmsgs++;

        if (any_display && is_tty)
        {
                clear_bot();
                so_enter();
                col += so_s_width;
        }

        col += less_printf(fmt, parg);

        if (!(any_display && is_tty))
        {
                putchr('\n');
                return;
        }

        putstr(return_to_continue);
        so_exit();
        col += sizeof(return_to_continue) + so_e_width;

        get_return();
        lower_left();

        if (col >= sc_width)
                /*
                 * Printing the message has probably scrolled the screen.
                 * {{ Unless the terminal doesn't have auto margins,
                 *    in which case we just hammered on the right margin. }}
                 */
                screen_trashed = 1;

        flush();
}

static char intr_to_abort[] = "... (interrupt to abort)";

/*
 * Output a message in the lower left corner of the screen
 * and don't wait for carriage return.
 * Usually used to warn that we are beginning a potentially
 * time-consuming operation.
 */
        public void
ierror(fmt, parg)
        char *fmt;
        PARG *parg;
{
        clear_bot();
        so_enter();
        (void) less_printf(fmt, parg);
        putstr(intr_to_abort);
        so_exit();
        flush();
        need_clr = 1;
}

/*
 * Output a message in the lower left corner of the screen
 * and return a single-character response.
 */
        public int
query(fmt, parg)
        char *fmt;
        PARG *parg;
{
        register int c;
        int col = 0;

        if (any_display && is_tty)
                clear_bot();

        (void) less_printf(fmt, parg);
        c = getchr();

        if (!(any_display && is_tty))
        {
                putchr('\n');
                return (c);
        }

        lower_left();
        if (col >= sc_width)
                screen_trashed = 1;
        flush();

        return (c);
}