floating point ext: add function documentation

[vim_extended.git] / src / os_riscos.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.
 */

#include "vim.h"

/*
 * os_riscos.c
 *
 * Thomas Leonard <tal197@ecs.soton.ac.uk>
 */

const char *__dynamic_da_name = "Vim heap"; /* Enable and name our dynamic area */
int ro_line_mode = TRUE;  /* For Ex mode we much echo chars to the screen ourselves */
int windowed;           /* Flag - are we running inside a text window? */
int WinLeft, WinTop;    /* We might be started inside a text window */
int ScrollTop;          /* Make cursor movements relative to ScrollTop. */

int old_escape_state = -1;
int old_cursor_state = -1;

#define rgb(r,g,b) ((b<<24) + (g<<16) + (r<<8))
#define NORMAL_FG 0x00000000
#define NORMAL_BG 0xffffffff

/* Convert a DOS colour number to an RGB palette entry.
 * Mappings from X11 rgb/txt file.
 */
    static int
map_colour(dos)
    int dos;            /* Standard DOS colour number. */
{
    switch (dos)
    {
        case 0: return 0;                       /* Black */
        case 1: return rgb(0,0,139);            /* DarkBlue */
        case 2: return rgb(0,100,0);            /* DarkGreen */
        case 3: return rgb(0,139,139);          /* DarkCyan */
        case 4: return rgb(139,0,0);            /* DarkRed */
        case 5: return rgb(139,0,139);          /* DarkMagenta */
        case 6: return rgb(165,42,42);          /* Brown, DarkYellow */
        case 7: return rgb(211,211,211);        /* LightGray, LightGrey, Gray, Grey */
        case 8: return rgb(169,169,169);        /* DarkGray, DarkGrey */
        case 9: return rgb(173,216,230);        /* Blue, LightBlue */
        case 10: return rgb(144,238,144);       /* Green, LightGreen */
        case 11: return rgb(224,255,255);       /* Cyan, LightCyan */
        case 12: return rgb(255,0,0);           /* Red, LightRed */
        case 13: return rgb(255,0,255);         /* Magenta, LightMagenta */
        case 14: return rgb(255,255,0);         /* Yellow, LightYellow */
        case 15: return rgb(255,255,255);       /* White */
    }
    return rgb(100,100,100);
}

    static void
text_fg(fg)
    int fg;             /* Foregound colour in the form &BBGGRR00 */
{
    xswi(ColourTrans_SetTextColour, fg, 0, 0, 0);
}

    static void
text_bg(bg)
    int         bg;     /* Backgound colour in the form &BBGGRR00 */
{
    xswi(ColourTrans_SetTextColour, bg, 0, 0, 1 << 7);
}

#define OUT_NORMAL 0
#define OUT_NUMBER 1            /* Reading in a number */

    void
mch_write(s, len)
    char_u  *s;
    int     len;
{
    static int mode = OUT_NORMAL;
    static int x, y;                    /* For reading numbers in. */

    if (!term_console)
    {
        /* Maybe we are running Vim remotely - don't interpret chars */
        while (len--)
        {
            char_u c = *s++;
            swi(OS_WriteC, c);
            /* We might need to send a CR too. This shouldn't
             * hurt if we don't need it, should it?
             */
            if (c == 10)
                swi(OS_WriteI + 13);
        }
        return;
    }

    while (len--)
    {
        char_u c = *s++;
        switch (mode)
        {
            case OUT_NUMBER:
                if (c < '0' || c > '9')
                {
                    mode = OUT_NORMAL;
                }
                else
                {
                    x = (x * 10) + c - '0';
                    continue;
                }
            /* note: no break here! */

            case OUT_NORMAL:
                switch (c)
                {
                    case 1:
                        /* Number (in decimal) follows. */
                        mode = OUT_NUMBER;
                        y = x;
                        x = 0;
                        break;
                    case 2:
                        /* Position cursor. */
                        swi(OS_WriteI + 31);
                        swi(OS_WriteC, x);
                        swi(OS_WriteC, y - ScrollTop);
                        break;
                    case 3:
                        /* Set scroll region. */
                        if (x == Rows -1 && y == 0 && !windowed)
                        {
                            /* Whole screen - remove text window.
                             * This is MUCH faster.
                             */
                            swi(OS_WriteI + 26);
                        }
                        else
                        {
                            /* Create a text window. */
                            swi(OS_WriteI + 28);
                            swi(OS_WriteC, WinLeft);
                            swi(OS_WriteC, WinTop + x);
                            swi(OS_WriteC, WinLeft + Columns - 1);
                            swi(OS_WriteC, WinTop + y);
                        }
                        ScrollTop = y;
                        break;
                    case 4:
                        /* Normal mode. */
                        text_fg(NORMAL_FG);
                        text_bg(NORMAL_BG);
                        break;
                    case 5:
                        /* Reverse mode. */
                        text_fg(NORMAL_BG);
                        text_bg(NORMAL_FG);
                        break;
                    case 10:
                        swi(OS_NewLine);
                        break;
                    case 14:
                        /* Cursor invisible. */
                        swi(OS_WriteN,
                             "\027\001\000\000\000\000\000\000\000\000",
                             10);
                        break;
                    case 15:
                        /* Cursor visible. */
                        swi(OS_WriteN,
                             "\027\001\002\000\000\000\000\000\000\000",
                             10);
                        break;
                    case 16:
                        /* Cursor very visible (flash) */
                        swi(OS_WriteN,
                             "\027\001\003\000\000\000\000\000\000\000",
                             10);
                    case 17:
                        /* Set foreground colour. */
                        text_fg(map_colour(x));
                        break;
                    case 18:
                        /* Set background colour. */
                        text_bg(map_colour(x));
                        break;
                    case 19:
                        /* Scroll text down. */
                        swi(OS_WriteN,
                             "\027\007\000\002\000\000\000\000\000\000",
                             10);
                        break;
                    default:
                        swi(OS_WriteC, c);
                }
                continue;

            default:
                printf("[output error]");
                mode = OUT_NORMAL;
        }
    }
}

/*
 * mch_inchar(): low level input funcion.
 * Get a characters from the keyboard.
 * Return the number of characters that are available.
 * If wtime == 0 do not wait for characters.
 * If wtime == n wait n msecs for characters.
 * If wtime == -1 wait forever for characters.
 *
 * TODO: call convert_input() for 'fileencoding' to 'encoding' conversion.
 */
    int
mch_inchar(buf, maxlen, wtime, tb_change_cnt)
    char_u  *buf;
    int     maxlen;
    long    wtime;
    int     tb_change_cnt;
{
    int got=0;
    unsigned int start_time = clock();

    if (ro_line_mode)
    {
        /* We're probably in Ex mode - get whole lines at a time. */

        static char_u   line_buffer[256];
        static int      remaining_chars = 0;
        static int      buf_pos = 0;

        /* Do we need to fetch another line? */
        if (remaining_chars == 0)
        {
            int         old_esc_state;
            swi(OS_Byte, 200, 1, 0xfe);
            old_esc_state = r1;

            buf_pos = 0;
            if (xswi(OS_ReadLine, line_buffer, 255, 0, 255) & (c_flag | v_flag))
            {
                got_int = TRUE;     /* ESC pressed */
                r1 = 0;
            }
            line_buffer[r1] = 13;
            remaining_chars = r1 + 1;   /* Count CR as part of input */

            swi(OS_Byte, 200, old_esc_state, 0);
        }

        /* Can we send the rest of the buffer back in one go? */
        if (remaining_chars <= maxlen)
        {
            int     got = remaining_chars;

            memcpy(buf, line_buffer + buf_pos, got);
            remaining_chars = 0;
            return  got;
        }

        /* Send as much as we can */
        memcpy(buf, line_buffer + buf_pos, maxlen);
        buf_pos += maxlen;
        remaining_chars -= maxlen;

        return maxlen;
    }

    if (!term_console)
    {
        /* Use OS_ReadC for all input.
         * Avoids problems with remote access getting interference from
         * the keyboard.
         */
        if (wtime == 0)
            return 0;       /* Ignore quick key checks */

        if (xswi(OS_ReadC) & c_flag)
        {
            got_int = TRUE;     /* ESC pressed - can this happen? */
            swi(OS_Byte, 124);  /* Clear Escape state */
            r0 = 0x1b;          /* It *might* not have been Escape! */
        }
        buf[0] = r0;
        return 1;
    }

    /*
     * OK, here's the plan:
     *
     * 1) Wait until wtime expires or we get a key
     * 2) Get keys until the keyboard buffer is empty or buf is full
     */

    while (xswi(OS_Byte,145,0) & c_flag)
    {
        /* Nothing at all in the keyboard buffer.
         * Has our time expired yet?
         */
        if ( (wtime != -1) && (clock() - start_time) >= wtime )
            return 0;           /* Nothing read - giving up */
    }

    /* We've got one char (in r2) - are there any more? */

    while (got < maxlen)
    {
        buf[got++] = r2;

        if (xswi(OS_Byte,145,0) & c_flag)
            return got;         /* Keyboard buffer empty */
    }
    return got;                 /* buf is full */
}

/*
 * return non-zero if a character is available
 */
    int
mch_char_avail()
{
    if (!term_console)
        return 0;           /* Can't tell */
    if (xswi(OS_Byte, 152, 0) & c_flag)
        return 0;
    return 1;
}

/* Find out how much free memory we have.
 * I don't know how to work this out exactly but, since we can claim
 * more memory from the OS, let's just report the free pool size.
 * Dynamic area 6 doesn't exist pre 3.6 according to StrongHelp, so
 * we'll use Wimp_SlotSize. If that fails (outside the desktop?)
 * then just return a big number and hope.
 */
    long_u
mch_avail_mem(special)
    int special;
{
    if (xswi(Wimp_SlotSize, -1, -1) & v_flag)
        return 0x7fffffff;
    return r2;
}

    void
mch_delay(msec, ignoreinput)
    long        msec;
    int         ignoreinput;
{
    int         start_time, time_now;
    int         csec = msec / 10;

    swi(OS_ReadMonotonicTime);
    start_time = r0;

    for (;;)
    {
        swi(OS_ReadMonotonicTime);
        time_now = r0;
        if (time_now - start_time > csec)
            return;
#ifdef FEAT_GUI
        /* In the GUI, allow other programs to run while waiting. */
        if (gui.in_use)
            gui_mch_wait_for_chars(start_time + csec);
#endif
    }
}

/*
 * If the machine has job control, use it to suspend the program,
 * otherwise fake it by starting a new shell.
 */
    void
mch_suspend()
{
    suspend_shell();
}

    void
mch_init()
{
    /*
     * Read window size first. Calls to mch_get_shellsize() will
     * simply return these values in future so that setting the
     * text window (used for scrolling) won't give strange results.
     */

    int buf[7] = {132, 135, 256, 257, 1, 2, -1};

    /* Command windows are no longer forced open, since if we are
     * in the desktop then we'll use the GUI version.
     * Opening a command window here messes up the GUI version startup
     */
#ifndef FEAT_GUI
    swi(OS_WriteI);
#endif
    swi(OS_ReadVduVariables, buf, buf);
    WinLeft = buf[0];
    WinTop  = buf[1];
    Columns = buf[2];
    Rows    = buf[3] + 1;       /* Seems to be one off (VduVars wrong?) */
    ScrollTop = 0;

    /* Are we running in a textwindow? */
    if (Rows == buf[5] + 1 && Columns == buf[4] + 1)
        windowed = 0;
    else
        windowed = 1;

    /* Choose a nice colour scheme. */
    text_fg(NORMAL_FG);
    text_bg(NORMAL_BG);
}

/*
 * Check_win checks whether we have an interactive stdout.
 */
/* ARGSUSED */
    int
mch_check_win(argc, argv)
    int     argc;
    char    **argv;
{
    return OK;
}

/*
 * Return TRUE if the input comes from a terminal, FALSE otherwise.
 */
    int
mch_input_isatty()
{
    if (xswi(OS_ChangeRedirection, -1, -1) & v_flag)
        return TRUE;            /* Error - TRUE is probably correct though */
    if (r0 == 0)
        return TRUE;
    return FALSE;
}

#ifdef FEAT_TITLE
    int
mch_can_restore_title()
{
    return FALSE;
}

    int
mch_can_restore_icon()
{
    return FALSE;
}


/*
 * Set the window title and icon.
 */
    void
mch_settitle(title, icon)
    char_u *title;
    char_u *icon;
{
    if (title == NULL)
        title = (char_u *) "<untitled>";
#ifdef FEAT_GUI
    if (gui.in_use && strcmp(title, gui.window_title))
    {
        int length;
        length = strlen(title);
        if (length >= gui.window_title_size)
            length = gui.window_title_size - 1;
        strncpy(gui.window_title, title, length);
        gui.window_title[length] = 0;
        ro_redraw_title(gui.window_handle);
    }
#endif
    return;
}

/*
 * Restore the window/icon title.
 * "which" is one of:
 *  1  only restore title
 *  2  only restore icon
 *  3  restore title and icon
 */
    void
mch_restore_title(which)
    int which;
{
    return;
}
#endif

/*
 * Insert user name in s[len].
 * Return OK if a name found.
 */
    int
mch_get_user_name(s, len)
    char_u  *s;
    int     len;
{
    /* RISC OS doesn't support user names. */
    *s = NUL;
    return FAIL;
}

/*
 * Insert host name in s[len].
 */

    void
mch_get_host_name(s, len)
    char_u  *s;
    int     len;
{
    if (xswi(OS_ReadVarVal, "Machine$Name", s, len, 0, 3) & v_flag)
    {
        /* Variable does not exist (normal operation) */
        vim_strncpy(s, "(unknown)", len - 1);
    }
}

/*
 * return process ID
 */
    long
mch_get_pid()
{
    if (xswi(Wimp_ReadSysInfo, 5) & v_flag)
        return 0;
    return r0;
}

/*
 * Get name of current directory into buffer 'buf' of length 'len' bytes.
 * Return OK for success, FAIL for failure.
 */
    int
mch_dirname(buf, len)
    char_u  *buf;
    int     len;
{
    if (xswi(OS_FSControl, 37, "@", buf, 0, 0, len) & v_flag)
        return FAIL;
    return OK;
}

/*
 * Get absolute file name into buffer 'buf' of length 'len' bytes.
 *
 * return FAIL for failure, OK for success
 */
    int
mch_FullName(fname, buf, len, force)
    char_u *fname, *buf;
    int len;
    int force;          /* Also expand when already absolute path name.
                         * Not used under RISC OS.
                         */
{
    if (xswi(OS_FSControl, 37, fname, buf, 0, 0, len) & v_flag)
        return FAIL;
    return OK;
}

/*
 * Return TRUE if "fname" does not depend on the current directory.
 */
    int
mch_isFullName(fname)
    char_u      *fname;
{
    if (strstr(fname, "::") && strstr(fname,".$."))
        return TRUE;
    return FALSE;
}

/*
 * Get file permissions for 'name'.
 * Returns -1 when it doesn't exist.
 */
    long
mch_getperm(name)
    char_u *name;
{
    struct stat statb;

    if (stat((char *)name, &statb))
        return -1;
    return statb.st_mode;
}

/*
 * set file permission for 'name' to 'perm'
 *
 * return FAIL for failure, OK otherwise
 */
    int
mch_setperm(name, perm)
    char_u  *name;
    long    perm;
{
    return (chmod((char *)name, (mode_t)perm) == 0 ? OK : FAIL);
}

/*
 * Set hidden flag for "name".
 */
/* ARGSUSED */
    void
mch_hide(name)
    char_u      *name;
{
    /* can't hide a file */
}

/*
 * return TRUE if "name" is a directory
 * return FALSE if "name" is not a directory
 * return FALSE for error
 */
    int
mch_isdir(name)
    char_u *name;
{
    if (xswi(OS_File, 17, name) & v_flag)
        return FALSE;
    if (r0 == 2 || r0 == 3)
        return TRUE;            /* Count image files as directories. */
    return FALSE;
}

/*
 * Return 1 if "name" can be executed, 0 if not.
 * Return -1 if unknown. Requires which to work.
 */
    int
mch_can_exe(name)
    char_u      *name;
{
    char_u      *buf;
    char_u      *p;
    int         retval;

    buf = alloc((unsigned)STRLEN(name) + 7);
    if (buf == NULL)
        return -1;
    sprintf((char *)buf, "which %s", name);
    p = get_cmd_output(buf, NULL, SHELL_SILENT);
    vim_free(buf);
    if (p == NULL)
        return -1;
    /* result can be: "name: Command not found" */
    retval = (*p != NUL && strstr((char *)p, "not found") == NULL);
    vim_free(p);
    return retval;
}

/*
 * Check what "name" is:
 * NODE_NORMAL: file or directory (or doesn't exist)
 * NODE_WRITABLE: writable device, socket, fifo, etc.
 * NODE_OTHER: non-writable things
 */
    int
mch_nodetype(name)
    char_u      *name;
{
    /* TODO */
    return NODE_NORMAL;
}

    void
mch_early_init()
{
    /* Turn off all the horrible filename munging in UnixLib. */
    int __riscosify_control = __RISCOSIFY_NO_PROCESS;
}

    void
mch_exit(r)
    int r;
{
    settmode(TMODE_COOK);
    exiting = TRUE;
    out_flush();
    ml_close_all(TRUE);         /* remove all memfiles */

#ifdef FEAT_GUI
    if (gui.in_use)
        gui_exit(r);
#endif
    swi(OS_NewLine);
    if (old_escape_state != -1)
        swi(OS_Byte, 229, old_escape_state, 0);
    if (old_cursor_state != -1)
        swi(OS_Byte, 4, old_cursor_state);
    exit(r);
}

    void
mch_settmode(tmode)
    int         tmode;      /* TMODE_RAW or TMODE_COOK */
{
    if (tmode == TMODE_COOK)
    {
        ro_line_mode = TRUE;
        return;
    }

    ro_line_mode = FALSE;

    if (term_console)
    {
        /* Block cursor. */
        swi(OS_WriteN,
                "\027\000\012\000\000\000\000\000\000\000",
                10);

        /* Disable the standard cursor key actions. */
        swi(OS_Byte, 4, 1);
        if (old_cursor_state == -1)
            old_cursor_state = r1;
    }

    /* Stop Escape from quitting Vim! */
    swi(OS_Byte, 229, 1, 0);
    if (old_escape_state == -1)
        old_escape_state = r1;
}

/*
 * set mouse clicks on or off (only works for xterms)
 */
    void
mch_setmouse(on)
    int     on;
{
}

/*
 * set screen mode, always fails.
 */
/* ARGSUSED */
    int
mch_screenmode(arg)
    char_u   *arg;
{
    EMSG(_(e_screenmode));
    return FAIL;
}

/*
 * Try to get the current window size.
 * Return OK when size could be determined, FAIL otherwise.
 * Simply return results stored by mch_init() if we are the
 * machine's console. If not, we don't know how big the screen is.
 */
    int
mch_get_shellsize()
{
    /* if size changed: screenalloc will allocate new screen buffers */
    return term_console ? OK : FAIL;
}

/*
 * Can't change the size.
 * Assume the user knows what he's doing and use the new values.
 */
    void
mch_set_shellsize()
{
    /* Assume the user knows what he's doing and use the new values. */
}

/*
 * Rows and/or Columns has changed.
 */
    void
mch_new_shellsize()
{
    /* Nothing to do. */
}

    int
mch_call_shell(cmd, options)
    char_u      *cmd;
    int         options;        /* SHELL_*, see vim.h */
{
    int         retval;
    int         tmode = cur_tmode;

    if (cmd == NULL)
        cmd = (char_u *) "GOS";

#ifdef FEAT_GUI
    if (gui.in_use)
        return gui_mch_call_shell(cmd, options);
#endif
    if (options & SHELL_COOKED)
        settmode(TMODE_COOK);           /* set to normal mode */
    MSG_PUTS("\n");

   /* I don't even want to think about what UnixLib must
    * be doing to allow this to work...
    */
    retval = system(cmd);
    if (retval && !(options & SHELL_SILENT))
        EMSG(strerror(EOPSYS));         /* Doesn't seem to set errno? */

    swi(OS_Byte, 229, 1, 0);            /* Re-disable escape */
    if (tmode == TMODE_RAW)
        settmode(TMODE_RAW);            /* set to raw mode */
    return retval ? FAIL : OK;
}

/*
 * Check for Escape being pressed right now.
 * [ different if !term_console? ]
 */
    void
mch_breakcheck()
{
    if (xswi(OS_Byte, 121, 0xf0) & v_flag)
        return;
    if (r1 == 0xff)
    {
        got_int = TRUE;
        swi(OS_Byte, 15, 1);    /* Flush input buffer */
    }
}

/*
 * Recursively expand one path component into all matching files and/or
 * directories.
 * "path" has backslashes before chars that are not to be expanded.
 * Return the number of matches found.
 */
    int
mch_expandpath(gap, path, flags)
    garray_T    *gap;   /* Grow array for results. */
    char_u      *path;
    int         flags;  /* EW_* flags */
{
    int         got;    /* Number of matches. */
    char_u      *pattern;

   /* Plan:
    *
    * 1) Get first part of path - no wildcards
    * 2) Get next path element (wildcarded)
    * 3) Get rest of path
    *
    * If (3) is nothing then only the leaf is wildcarded - add to gap
    * Otherwise call recursively for each path in (2), passing (3)
    *
    * This is just the header function.
    */

    /* We must be able to modifiy path, so make a copy */
    pattern = vim_strsave(path);
    if (pattern == NULL)
        return 0;
    got = expand_section(gap, (char_u *)"", pattern, flags);
    vim_free(pattern);
    return got;
}

/*
 * expand_section(gap, "$.Dir1.Dir2", "ABBA*.myleaf##")
 *
 * calls expand_section(gap, "$.Dir1.Dir2.ABBA_Gold", "myleaf##")
 *   and expand_section(gap, "$.Dir1.Dir2.ABBA_Live", "myleaf##")
 *
 * If rest is just a leaf then all matches are added to gap.
 *
 * Returns number of items added to gap.
 */
    int
expand_section(gap, root, rest, flags)
    garray_T    *gap;
    char_u      *root;  /* Non-wildcarded path to search */
    char_u      *rest;  /* Wildcarded remainder of path */
    int         flags;  /* Add dirs/files/missing objects. */
{
    static char_u buf[MAXPATHL];        /* Temporary buffer. */
    char_u dir[MAXPATHL];
    int start_element = -1;             /* Start of wildcarded element */
    char_u c;
    int i;
    int got, dir_pos;
    int buflen;                 /* Chars used in buf[] */
    int colon = 0;              /* Dir ends in ':' */

    buflen = strlen(root);
    STRNCPY(buf, root, buflen); /* Copy root into buffer. */

   /*
    * Find end of nonwildcarded section.
    * Count ':' as a path sep since Vim:Bug* is a valid pathname.
    */

    for (i = 0; c = rest[i]; i++)
    {
        if (c == PATHSEP)
        {
            start_element = i;
            colon = 0;
        }
        if (c == ':')
        {
            start_element = i + 1;
            colon = 1;
        }
        if (c == '#' || c == '*')
            break;
    }
    if (c == 0)
        start_element = i;

   /*
    * start_element +> terminator for non-wildcarded section.
    * Transfer this bit into buf.
    */
    if (buflen + start_element + 4 >= MAXPATHL)
       return 0;                        /* Buffer full */
    if (start_element >= 0)
    {
        if (*root && !colon)
            buf[buflen++] = PATHSEP;
        strncpy(buf + buflen, rest, start_element);
        buflen += start_element;
    }
    buf[buflen] = 0;

   /*
    * Did we reach the end of the string without hitting any wildcards?
    */
    if (c == 0)
    {
        /* Yes - add combined path to grow array and return. */
        addfile(gap, buf, flags);
        return 1;
    }

    if (start_element < 0 || !colon)
        start_element++;
    rest += start_element;

   /*
    * rest does contain wildcards if we get here.
    *
    * Now : have we reached the leaf names part yet?
    * If so, add all matches (files and dirs) to gap.
    * If not, get next path element and scan all matching directories.
    */

    start_element = -1;
    for (i = 0; rest[i]; i++)
    {
        if (rest[i] == '.')
        {
            start_element = i;
            rest[i] = 0;                /* Break string here. */
            break;
        }
    }

    /* If start_element is -1 then we are matching leaf names */

    r3 = 0;                     /* Number of objs read. */
    dir_pos = 0;                /* Position through directory. */
    got = 0;                    /* Files added so far. */
    while (dir_pos != -1)
    {
        buf[buflen] = 0;
        if (xswi(OS_GBPB, 9,
                buf,                            /* Directory to scan. */
                buf + buflen + (1 - colon),     /* Buffer for result. */
                1,                      /* Number of objects to read. */
                dir_pos,                /* Search position. */
                MAXPATHL - 2 - buflen,  /* Size of result buffer. */
                rest)                   /* Wildcarded leafname. */
                        & v_flag)
        {
            EMSG(r0 + 4);
            r4 = -1;
        }
        dir_pos = r4;           /* r4 corrupted by addfile() */
        if (r3 > 0)
        {
            char_u *path = buf;
            if (buflen == 0)
                path++;                 /* Don't do '.File' */
            else if (!colon)
                buf[buflen] = '.';              /* Join path and leaf */

           /* Path -> full path of object found */
            if (start_element == -1)
            {
                addfile(gap, path, flags);
                got++;
            }
            else
            {
               /* Scan into subdirectories and images; ignore files */
                swi(OS_File, 17, path);
                if (r0 == 2 || r0 == 3)
                    got += expand_section(gap,
                                                path,
                                                rest + start_element + 1,
                                                flags);
            }
        }
    }

    /* Restore the dot if we removed it. */
    if (start_element >= 0)
        rest[start_element] = '.';
    return got;
}

/*
 * mch_expand_wildcards() - this code does wild-card pattern matching using
 * the shell. It isn't used under RISC OS.
 *
 * return OK for success, FAIL for error (you may lose some memory) and put
 * an error message in *file.
 *
 * num_pat is number of input patterns
 * pat is array of pointers to input patterns
 * num_file is pointer to number of matched file names
 * file is pointer to array of pointers to matched file names
 */
    int
mch_expand_wildcards(num_pat, pat, num_file, file, flags)
    int             num_pat;
    char_u        **pat;
    int            *num_file;
    char_u       ***file;
    int             flags;              /* EW_* flags */
{
    /* This doesn't get called unless SPECIAL_WILDCHAR is defined. */
    return FAIL;
}

/*
 * Return TRUE if "p" contains wildcards which can be expanded by
 * mch_expandpath().
 */
    int
mch_has_exp_wildcard(p)
    char_u      *p;
{
    if (vim_strpbrk((char_u *)"*#", p))
        return TRUE;
    return FALSE;
}

/* Return TRUE if "p" contains wildcards. */
    int
mch_has_wildcard(p)
    char_u      *p;
{
    if (vim_strpbrk((char_u *)"*#`", p))
        return TRUE;
    return FALSE;
}

    int                 /* see Unix unlink(2) */
mch_remove(file)
    char_u *file;       /* Name of file to delete. */
{
    if (xswi(OS_FSControl, 27, file, 0, 0) & v_flag)
        return EXIT_FAILURE;
    return EXIT_SUCCESS;
}

/* Try to make existing scripts work without modification.
 * Return a pointer to the new string (freed by caller), or NULL
 *
 * Two main cases:
 * - Absolute : $VIM/syntax/help.vim
 * - Relative : Adfs::4.$.!Vim.Resources.Syntax/help.vim
 */
    char_u *
mch_munge_fname(fname)
    char_u *fname;
{
    char_u c;
    int len;
    char_u *retval;

    retval = fname = vim_strsave(fname);
    if (fname == NULL)
        return NULL;

    if (strncmp(fname, "$VIM/", 5) == 0)
    {
        strncpy(fname, "Vim:", 4);
        for (fname += 5; c = *fname; fname++)
        {
            if (c == '.')
                break;
            if (c == '/')
                fname[-1] = '.';
            else
                fname[-1] = c;
        }
        fname[-1] = '\0';
    }
    else
    {
        /* Check to see if the file exists without modification. */
        if (xswi(OS_File, 17, fname) & v_flag)
            r0 == 0;            /* Invalid filename? */
        if (r0)
            return retval;

        len = strlen(fname);
        if (strcmp(fname + len - 4, ".vim") == 0)
        {
            fname[len - 4] = '\0';
            for (; c = *fname; fname++)
            {
                if (c == '/')
                    *fname = '.';
            }
        }
    }
    return retval;
}

/* QuickFix reads munged names from the error file.
 * Correct them.
 */
    int
ro_buflist_add(old_name)
    char_u  *old_name;  /* Name of file found by quickfix */
{
    char_u  *fname;
    char_u  *leaf;      /* Pointer to start of leaf in old_name */
    char_u  *ptr;
    char_u  c;
    int     retval;

    if (old_name == NULL)
        return buflist_add(NULL, 0);

    /* Copy the name so we can mess around with it. */
    fname = vim_strsave(old_name);
    if (fname == NULL)
        /* Out of memory - can't modify name */
        return buflist_add(old_name, 0);

    /* Change `dir/main.c' into `dir.c.main' */
    leaf = fname;
    for (ptr = fname; c = *ptr; ptr++)
    {
        if (c == '/')
        {
            leaf = ptr + 1;
            *ptr = '.';
        }
        else if (c == '.')
            break;
    }
    if (c == '.')
    {
        /* Change `main.c' into `c.main'
         *        |    |
         *      leaf  ptr
         */
        ptr += old_name - fname;
        *ptr = '\0';
        sprintf(leaf,
                "%s.%s",
                ptr + 1,
                leaf - fname + old_name);
    }

    retval = buflist_add(fname, 0);
    free(fname);
    return retval;
}

/* Change the current directory.
 * Strip trailing dots to make it easier to use with filename completion.
 * Return 0 for success, -1 for failure.
 */
    int
mch_chdir(dir)
    char_u  *dir;
{
    int     length;
    int     retval;
    char_u  *new_dir;

    length = strlen(dir);
    if (dir[length - 1] != '.')
        return chdir(dir);          /* No trailing dots - nothing to do. */
    new_dir = vim_strsave(dir);
    if (new_dir == NULL)
        return chdir(dir);          /* Can't allocate memory. */

    while (new_dir[--length] == '.')
        new_dir[length] = '\0';

    retval = chdir(new_dir);
    vim_free(new_dir);
    return retval;
}

/* Examine the named file, and set the 'osfiletype' option
 * (in curbuf) to the file's type.
 */
    void
mch_read_filetype(file)
    char_u  *file;
{
    int     type;
    char_u  type_string[9];
    int     i;

    if (xswi(OS_File, 23, file) & v_flag)
        type = 0xfff;           /* Default to Text */
    else
        type = r6;

    /* Type is the numerical value - see if we have a textual equivalent */
    swi(OS_FSControl, 18, 0, type);
    ((int *) type_string)[0] = r2;
    ((int *) type_string)[1] = r3;
    type_string[8] = 0;
    for (i = 0; type_string[i] > ' '; i++)
        ;
    type_string[i] = 0;

    set_string_option_direct("osfiletype", -1, type_string, OPT_FREE, 0);
    return;
}

    void
mch_set_filetype(file, type)
    char_u  *file;
    char_u  *type;
{
    if (xswi(OS_FSControl, 31, type) & v_flag)
    {
        EMSG(_("E366: Invalid 'osfiletype' option - using Text"));
        r2 = 0xfff;
    }

    swi(OS_File, 18, file, r2);
}

/* Return TRUE if the file's type matches 'type'
 * RISC OS types always start with '&'
 */
    int
mch_check_filetype(fname, type)
    char_u  *fname;
    char_u  *type;
{
    int     value;
    char    *end;

    if (*type != '&')
        return FALSE;

    value = strtol(type + 1, &end, 16);
    if (*end)
        return FALSE;           /* Invalid type (report error?) */

    if (xswi(OS_File, 23, fname) & v_flag)
        return FALSE;           /* Invalid filename? */

    return (r0 && r6 == value);
}