rc.conf: Add and document the missing root_rw_mount=YES

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

/*
 * Copyright (C) 1984-2023  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, see the README file.
 */


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

#include "less.h"
#if MSDOS_COMPILER==WIN32C
#include "windows.h"
#ifndef COMMON_LVB_UNDERSCORE
#define COMMON_LVB_UNDERSCORE 0x8000
#endif
#endif

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

extern int sigs;
extern int sc_width;
extern int so_s_width, so_e_width;
extern int screen_trashed;
extern int is_tty;
extern int oldbot;
extern char intr_char;

#if MSDOS_COMPILER==WIN32C || 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;
extern int sgr_mode;
#if MSDOS_COMPILER==WIN32C
extern int vt_enabled;
#endif
#endif

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

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

        final_attr = AT_NORMAL;

        for (i = 0;  (c = gline(i, &a)) != '\0';  i++)
        {
                at_switch(a);
                final_attr = a;
                if (c == '\b')
                        putbs();
                else
                        putchr(c);
        }

        at_exit();
}

static char obuf[OUTBUF_SIZE];
static char *ob = obuf;
static int outfd = 2; /* stderr */

#if MSDOS_COMPILER==WIN32C || MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
static void win_flush(void)
{
        if (ctldisp != OPT_ONPLUS || (vt_enabled && sgr_mode))
                WIN32textout(obuf, ob - 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;
                static int fg, fgi, bg, bgi;
                static int at;
                int f, b;
#if MSDOS_COMPILER==WIN32C
                /* Screen colors used by 3x and 4x SGR commands. */
                static unsigned char screen_color[] = {
                        0, /* BLACK */
                        FOREGROUND_RED,
                        FOREGROUND_GREEN,
                        FOREGROUND_RED|FOREGROUND_GREEN,
                        FOREGROUND_BLUE, 
                        FOREGROUND_BLUE|FOREGROUND_RED,
                        FOREGROUND_BLUE|FOREGROUND_GREEN,
                        FOREGROUND_BLUE|FOREGROUND_GREEN|FOREGROUND_RED
                };
#else
                static enum COLORS screen_color[] = {
                        BLACK, RED, GREEN, BROWN,
                        BLUE, MAGENTA, CYAN, LIGHTGRAY
                };
#endif

                if (fg == 0 && bg == 0)
                {
                        fg  = nm_fg_color & 7;
                        fgi = nm_fg_color & 8;
                        bg  = nm_bg_color & 7;
                        bgi = nm_bg_color & 8;
                }
                for (anchor = p_next = obuf;
                         (p_next = memchr(p_next, ESC, ob - p_next)) != NULL; )
                {
                        p = p_next;
                        if (p[1] == '[')  /* "ESC-[" sequence */
                        {
                                if (p > anchor)
                                {
                                        /*
                                         * If some chars seen since
                                         * the last escape sequence,
                                         * write them out to the screen.
                                         */
                                        WIN32textout(anchor, p-anchor);
                                        anchor = p;
                                }
                                p += 2;  /* Skip the "ESC-[" */
                                if (is_ansi_end(*p))
                                {
                                        /*
                                         * Handle null escape sequence
                                         * "ESC[m", which restores
                                         * the normal color.
                                         */
                                        p++;
                                        anchor = p_next = p;
                                        fg  = nm_fg_color & 7;
                                        fgi = nm_fg_color & 8;
                                        bg  = nm_bg_color & 7;
                                        bgi = nm_bg_color & 8;
                                        at  = 0;
                                        WIN32setcolors(nm_fg_color, nm_bg_color);
                                        continue;
                                }
                                p_next = p;
                                at &= ~32;

                                /*
                                 * Select foreground/background colors
                                 * based on the escape sequence. 
                                 */
                                while (!is_ansi_end(*p))
                                {
                                        char *q;
                                        long code = strtol(p, &q, 10);

                                        if (*q == '\0')
                                        {
                                                /*
                                                 * Incomplete sequence.
                                                 * Leave it unprocessed
                                                 * in the buffer.
                                                 */
                                                int slop = (int) (q - anchor);
                                                /* {{ strcpy args overlap! }} */
                                                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++;
                                                at |= 32;
                                        }

                                        switch (code)
                                        {
                                        default:
                                        /* case 0: all attrs off */
                                                fg = nm_fg_color & 7;
                                                bg = nm_bg_color & 7;
                                                at &= 32;
                                                /*
                                                 * \e[0m use normal
                                                 * intensities, but
                                                 * \e[0;...m resets them
                                                 */
                                                if (at & 32)
                                                {
                                                        fgi = 0;
                                                        bgi = 0;
                                                } else
                                                {
                                                        fgi = nm_fg_color & 8;
                                                        bgi = nm_bg_color & 8;
                                                }
                                                break;
                                        case 1: /* bold on */
                                                fgi = 8;
                                                at |= 1;
                                                break;
                                        case 3: /* italic on */
                                        case 7: /* inverse on */
                                                at |= 2;
                                                break;
                                        case 4: /* underline on */
                                                bgi = 8;
                                                at |= 4;
                                                break;
                                        case 5: /* slow blink on */
                                        case 6: /* fast blink on */
                                                bgi = 8;
                                                at |= 8;
                                                break;
                                        case 8: /* concealed on */
                                                at |= 16;
                                                break;
                                        case 22: /* bold off */
                                                fgi = 0;
                                                at &= ~1;
                                                break;
                                        case 23: /* italic off */
                                        case 27: /* inverse off */
                                                at &= ~2;
                                                break;
                                        case 24: /* underline off */
                                                bgi = 0;
                                                at &= ~4;
                                                break;
                                        case 28: /* concealed off */
                                                at &= ~16;
                                                break;
                                        case 30: case 31: case 32:
                                        case 33: case 34: case 35:
                                        case 36: case 37:
                                                fg = screen_color[code - 30];
                                                at |= 32;
                                                break;
                                        case 39: /* default fg */
                                                fg = nm_fg_color & 7;
                                                at |= 32;
                                                break;
                                        case 40: case 41: case 42:
                                        case 43: case 44: case 45:
                                        case 46: case 47:
                                                bg = screen_color[code - 40];
                                                at |= 32;
                                                break;
                                        case 49: /* default bg */
                                                bg = nm_bg_color & 7;
                                                at |= 32;
                                                break;
                                        }
                                        p = q;
                                }
                                if (!is_ansi_end(*p) || p == p_next)
                                        break;
                                /*
                                 * In SGR mode, the ANSI sequence is
                                 * always honored; otherwise if an attr
                                 * is used by itself ("\e[1m" versus
                                 * "\e[1;33m", for example), set the
                                 * color assigned to that attribute.
                                 */
                                if (sgr_mode || (at & 32))
                                {
                                        if (at & 2)
                                        {
                                                f = bg | bgi;
                                                b = fg | fgi;
                                        } else
                                        {
                                                f = fg | fgi;
                                                b = bg | bgi;
                                        }
                                } else
                                {
                                        if (at & 1)
                                        {
                                                f = bo_fg_color;
                                                b = bo_bg_color;
                                        } else if (at & 2)
                                        {
                                                f = so_fg_color;
                                                b = so_bg_color;
                                        } else if (at & 4)
                                        {
                                                f = ul_fg_color;
                                                b = ul_bg_color;
                                        } else if (at & 8)
                                        {
                                                f = bl_fg_color;
                                                b = bl_bg_color;
                                        } else
                                        {
                                                f = nm_fg_color;
                                                b = nm_bg_color;
                                        }
                                }
                                if (at & 16)
                                        f = b ^ 8;
#if MSDOS_COMPILER==WIN32C
                                f &= 0xf | COMMON_LVB_UNDERSCORE;
#else
                                f &= 0xf;
#endif
                                b &= 0xf;
                                WIN32setcolors(f, b);
                                p_next = anchor = p + 1;
                        } else
                                p_next++;
                }

                /* Output what's left in the buffer.  */
                WIN32textout(anchor, ob - anchor);
        }
        ob = obuf;
}
#endif

/*
 * 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(void)
{
        int n;

        n = (int) (ob - obuf);
        if (n == 0)
                return;
        ob = obuf;

#if MSDOS_COMPILER==MSOFTC
        if (interactive())
        {
                obuf[n] = '\0';
                _outtext(obuf);
                return;
        }
#else
#if MSDOS_COMPILER==WIN32C || MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
        if (interactive())
        {
                ob = obuf + n;
                *ob = '\0';
                win_flush();
                return;
        }
#endif
#endif

        if (write(outfd, obuf, n) != n)
                screen_trashed = 1;
}

/*
 * Set the output file descriptor (1=stdout or 2=stderr).
 */
public void set_output(int fd)
{
        flush();
        outfd = fd;
}

/*
 * Output a character.
 */
public int putchr(int c)
{
#if 0 /* fake UTF-8 output for testing */
        extern int utf_mode;
        if (utf_mode)
        {
                static char ubuf[MAX_UTF_CHAR_LEN];
                static int ubuf_len = 0;
                static int ubuf_index = 0;
                if (ubuf_len == 0)
                {
                        ubuf_len = utf_len(c);
                        ubuf_index = 0;
                }
                ubuf[ubuf_index++] = c;
                if (ubuf_index < ubuf_len)
                        return c;
                c = get_wchar(ubuf) & 0xFF;
                ubuf_len = 0;
        }
#endif
        clear_bot_if_needed();
#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;
        at_prompt = 0;
        return (c);
}

public void clear_bot_if_needed(void)
{
        if (!need_clr)
                return;
        need_clr = 0;
        clear_bot();
}

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


/*
 * Convert an integral type to a string.
 */
#define TYPE_TO_A_FUNC(funcname, type) \
void funcname(type num, char *buf, int radix) \
{ \
        int neg = (num < 0); \
        char tbuf[INT_STRLEN_BOUND(num)+2]; \
        char *s = tbuf + sizeof(tbuf); \
        if (neg) num = -num; \
        *--s = '\0'; \
        do { \
                *--s = "0123456789ABCDEF"[num % radix]; \
        } while ((num /= radix) != 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)

/*
 * Convert a string to an integral type.  Return ((type) -1) on overflow.
 */
#define STR_TO_TYPE_FUNC(funcname, type) \
type funcname(char *buf, char **ebuf, int radix) \
{ \
        type val = 0; \
        int v = 0; \
        for (;; buf++) { \
                char c = *buf; \
                int digit = (c >= '0' && c <= '9') ? c - '0' : (c >= 'a' && c <= 'f') ? c - 'a' + 10 : (c >= 'A' && c <= 'F') ? c - 'A' + 10 : -1; \
                if (digit < 0 || digit >= radix) break; \
                v |= ckd_mul(&val, val, radix); \
                v |= ckd_add(&val, val, digit); \
        } \
        if (ebuf != NULL) *ebuf = buf; \
        return v ? -1 : val; \
}

STR_TO_TYPE_FUNC(lstrtopos, POSITION)
STR_TO_TYPE_FUNC(lstrtoi, int)
STR_TO_TYPE_FUNC(lstrtoul, unsigned long)

/*
 * Print an integral type.
 */
#define IPRINT_FUNC(funcname, type, typetoa) \
static int funcname(type num, int radix) \
{ \
        char buf[INT_STRLEN_BOUND(num)]; \
        typetoa(num, buf, radix); \
        putstr(buf); \
        return (int) strlen(buf); \
}

IPRINT_FUNC(iprint_int, int, inttoa)
IPRINT_FUNC(iprint_linenum, LINENUM, linenumtoa)

/*
 * This function implements printf-like functionality
 * using a more portable argument list mechanism than printf's.
 *
 * {{ This paranoia about the portability of printf dates from experiences
 *    with systems in the 1980s and is of course no longer necessary. }}
 */
public int less_printf(char *fmt, PARG *parg)
{
        char *s;
        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, 10);
                                parg++;
                                break;
                        case 'x':
                                col += iprint_int(parg->p_int, 16);
                                parg++;
                                break;
                        case 'n':
                                col += iprint_linenum(parg->p_linenum, 10);
                                parg++;
                                break;
                        case 'c':
                                s = prchar(parg->p_char);
                                parg++;
                                while (*s != '\0')
                                {
                                        putchr(*s++);
                                        col++;
                                }
                                break;
                        case '%':
                                putchr('%');
                                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(void)
{
        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(char *fmt, PARG *parg)
{
        int col = 0;
        static char return_to_continue[] = "  (press RETURN)";

        errmsgs++;

        if (!interactive())
        {
                less_printf(fmt, parg);
                putchr('\n');
                return;
        }

        if (!oldbot)
                squish_check();
        at_exit();
        clear_bot();
        at_enter(AT_STANDOUT|AT_COLOR_ERROR);
        col += so_s_width;
        col += less_printf(fmt, parg);
        putstr(return_to_continue);
        at_exit();
        col += sizeof(return_to_continue) + so_e_width;

        get_return();
        lower_left();
        clear_eol();

        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();
}

/*
 * 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.
 */
static void ierror_suffix(char *fmt, PARG *parg, char *suffix1, char *suffix2, char *suffix3)
{
        at_exit();
        clear_bot();
        at_enter(AT_STANDOUT|AT_COLOR_ERROR);
        (void) less_printf(fmt, parg);
        putstr(suffix1);
        putstr(suffix2);
        putstr(suffix3);
        at_exit();
        flush();
        need_clr = 1;
}

public void ierror(char *fmt, PARG *parg)
{
        ierror_suffix(fmt, parg, "... (interrupt to abort)", "", "");
}

public void ixerror(char *fmt, PARG *parg)
{
        if (!supports_ctrl_x())
                ierror(fmt, parg);
        else
                ierror_suffix(fmt, parg,
                        "... (", prchar(intr_char), " or interrupt to abort)");
}

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

        if (interactive())
                clear_bot();

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

        if (interactive())
        {
                lower_left();
                if (col >= sc_width)
                        screen_trashed = 1;
                flush();
        } else
        {
                putchr('\n');
        }

        if (c == 'Q')
                quit(QUIT_OK);
        return (c);
}