opttbl.c

/*
 * Copyright (C) 1984-2022  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.
 */


/*
 * The option table.
 */

#include "less.h"
#include "option.h"

/*
 * Variables controlled by command line options.
 */
public int quiet;               /* Should we suppress the audible bell? */
public int how_search;          /* Where should forward searches start? */
public int top_scroll;          /* Repaint screen from top?
                                   (alternative is scroll from bottom) */
public int pr_type;             /* Type of prompt (short, medium, long) */
public int bs_mode;             /* How to process backspaces */
public int know_dumb;           /* Don't complain about dumb terminals */
public int quit_at_eof;         /* Quit after hitting end of file twice */
public int quit_if_one_screen;  /* Quit if EOF on first screen */
public int squeeze;             /* Squeeze multiple blank lines into one */
public int tabstop;             /* Tab settings */
public int back_scroll;         /* Repaint screen on backwards movement */
public int forw_scroll;         /* Repaint screen on forward movement */
public int caseless;            /* Do "caseless" searches */
public int linenums;            /* Use line numbers */
public int autobuf;             /* Automatically allocate buffers as needed */
public int bufspace;            /* Max buffer space per file (K) */
public int ctldisp;             /* Send control chars to screen untranslated */
public int force_open;          /* Open the file even if not regular file */
public int swindow;             /* Size of scrolling window */
public int jump_sline;          /* Screen line of "jump target" */
public long jump_sline_fraction = -1;
public long shift_count_fraction = -1;
public int chopline;            /* Truncate displayed lines at screen width */
public int no_init;             /* Disable sending ti/te termcap strings */
public int no_keypad;           /* Disable sending ks/ke termcap strings */
public int twiddle;             /* Show tildes after EOF */
public int show_attn;           /* Hilite first unread line */
public int shift_count;         /* Number of positions to shift horizontally */
public int status_col;          /* Display a status column */
public int use_lessopen;        /* Use the LESSOPEN filter */
public int quit_on_intr;        /* Quit on interrupt */
public int follow_mode;         /* F cmd Follows file desc or file name? */
public int oldbot;              /* Old bottom of screen behavior {{REMOVE}} */
public int opt_use_backslash;   /* Use backslash escaping in option parsing */
public char rscroll_char;       /* Char which marks chopped lines with -S */
public int rscroll_attr;        /* Attribute of rscroll_char */
public int no_hist_dups;        /* Remove dups from history list */
public int mousecap;            /* Allow mouse for scrolling */
public int wheel_lines;         /* Number of lines to scroll on mouse wheel scroll */
public int perma_marks;         /* Save marks in history file */
public int linenum_width;       /* Width of line numbers */
public int status_col_width;    /* Width of status column */
public int incr_search;         /* Incremental search */
public int use_color;           /* Use UI color */
public int want_filesize;       /* Scan to EOF if necessary to get file size */
public int status_line;         /* Highlight entire marked lines */
public int header_lines;        /* Freeze header lines at top of screen */
public int header_cols;         /* Freeze header columns at left of screen */
public int nonum_headers;       /* Don't give headers line numbers */
public int redraw_on_quit;      /* Redraw last screen after term deinit */
public int def_search_type;     /* */
public int exit_F_on_close;     /* Exit F command when input closes */
#if HILITE_SEARCH
public int hilite_search;       /* Highlight matched search patterns? */
#endif

public int less_is_more = 0;    /* Make compatible with POSIX more */

/*
 * Long option names.
 */
static struct optname a_optname      = { "search-skip-screen",   NULL };
static struct optname b_optname      = { "buffers",              NULL };
static struct optname B__optname     = { "auto-buffers",         NULL };
static struct optname c_optname      = { "clear-screen",         NULL };
static struct optname d_optname      = { "dumb",                 NULL };
static struct optname D__optname     = { "color",                NULL };
static struct optname e_optname      = { "quit-at-eof",          NULL };
static struct optname f_optname      = { "force",                NULL };
static struct optname F__optname     = { "quit-if-one-screen",   NULL };
#if HILITE_SEARCH
static struct optname g_optname      = { "hilite-search",        NULL };
#endif
static struct optname h_optname      = { "max-back-scroll",      NULL };
static struct optname i_optname      = { "ignore-case",          NULL };
static struct optname j_optname      = { "jump-target",          NULL };
static struct optname J__optname     = { "status-column",        NULL };
#if USERFILE
static struct optname k_optname      = { "lesskey-file",         NULL };
#if HAVE_LESSKEYSRC
static struct optname ks_optname     = { "lesskey-src",          NULL };
#endif /* HAVE_LESSKEYSRC */
#endif
static struct optname K__optname     = { "quit-on-intr",         NULL };
static struct optname L__optname     = { "no-lessopen",          NULL };
static struct optname m_optname      = { "long-prompt",          NULL };
static struct optname n_optname      = { "line-numbers",         NULL };
#if LOGFILE
static struct optname o_optname      = { "log-file",             NULL };
static struct optname O__optname     = { "LOG-FILE",             NULL };
#endif
static struct optname p_optname      = { "pattern",              NULL };
static struct optname P__optname     = { "prompt",               NULL };
static struct optname q2_optname     = { "silent",               NULL };
static struct optname q_optname      = { "quiet",                &q2_optname };
static struct optname r_optname      = { "raw-control-chars",    NULL };
static struct optname s_optname      = { "squeeze-blank-lines",  NULL };
static struct optname S__optname     = { "chop-long-lines",      NULL };
#if TAGS
static struct optname t_optname      = { "tag",                  NULL };
static struct optname T__optname     = { "tag-file",             NULL };
#endif
static struct optname u_optname      = { "underline-special",    NULL };
static struct optname V__optname     = { "version",              NULL };
static struct optname w_optname      = { "hilite-unread",        NULL };
static struct optname x_optname      = { "tabs",                 NULL };
static struct optname X__optname     = { "no-init",              NULL };
static struct optname y_optname      = { "max-forw-scroll",      NULL };
static struct optname z_optname      = { "window",               NULL };
static struct optname quote_optname  = { "quotes",               NULL };
static struct optname tilde_optname  = { "tilde",                NULL };
static struct optname query_optname  = { "help",                 NULL };
static struct optname pound_optname  = { "shift",                NULL };
static struct optname keypad_optname = { "no-keypad",            NULL };
static struct optname oldbot_optname = { "old-bot",              NULL };
static struct optname follow_optname = { "follow-name",          NULL };
static struct optname use_backslash_optname = { "use-backslash", NULL };
static struct optname rscroll_optname = { "rscroll", NULL };
static struct optname nohistdups_optname = { "no-histdups",      NULL };
static struct optname mousecap_optname = { "mouse",              NULL };
static struct optname wheel_lines_optname = { "wheel-lines",     NULL };
static struct optname perma_marks_optname = { "save-marks",      NULL };
static struct optname linenum_width_optname = { "line-num-width", NULL };
static struct optname status_col_width_optname = { "status-col-width", NULL };
static struct optname incr_search_optname = { "incsearch",       NULL };
static struct optname use_color_optname = { "use-color",         NULL };
static struct optname want_filesize_optname = { "file-size",     NULL };
static struct optname status_line_optname = { "status-line",     NULL };
static struct optname header_optname = { "header",               NULL };
static struct optname nonum_headers_optname = { "no-number-headers", NULL };
static struct optname redraw_on_quit_optname = { "redraw-on-quit", NULL };
static struct optname search_type_optname = { "search-options", NULL };
static struct optname exit_F_on_close_optname = { "exit-follow-on-close", NULL };
#if LESSTEST
static struct optname ttyin_name_optname = { "tty",              NULL };
static struct optname rstat_optname  = { "rstat",                NULL };
#endif /*LESSTEST*/


/*
 * Table of all options and their semantics.
 *
 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are
 * the description of the option when set to 0, 1 or 2, respectively.
 * For NUMBER options, odesc[0] is the prompt to use when entering
 * a new value, and odesc[1] is the description, which should contain
 * one %d which is replaced by the value of the number.
 * For STRING options, odesc[0] is the prompt to use when entering
 * a new value, and odesc[1], if not NULL, is the set of characters
 * that are valid in the string.
 */
static struct loption option[] =
{
    { 'a', &a_optname,
        TRIPLE, OPT_ONPLUS, &how_search, NULL,
        {
            "Search includes displayed screen",
            "Search skips displayed screen",
            "Search includes all of displayed screen"
        }
    },

    { 'b', &b_optname,
        NUMBER|INIT_HANDLER, 64, &bufspace, opt_b,
        {
            "Max buffer space per file (K): ",
            "Max buffer space per file: %dK",
            NULL
        }
    },
    { 'B', &B__optname,
        BOOL, OPT_ON, &autobuf, NULL,
        {
            "Don't automatically allocate buffers",
            "Automatically allocate buffers when needed",
            NULL
        }
    },
    { 'c', &c_optname,
        TRIPLE, OPT_OFF, &top_scroll, NULL,
        {
            "Repaint by scrolling from bottom of screen",
            "Repaint by painting from top of screen",
            "Repaint by painting from top of screen"
        }
    },
    { 'd', &d_optname,
        BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL,
        {
            "Assume intelligent terminal",
            "Assume dumb terminal",
            NULL
        }
    },
    { 'D', &D__optname,
        STRING|REPAINT|NO_QUERY, 0, NULL, opt_D,
        {
            "color desc: ",
            NULL,
            NULL
        }
    },
    { 'e', &e_optname,
        TRIPLE, OPT_OFF, &quit_at_eof, NULL,
        {
            "Don't quit at end-of-file",
            "Quit at end-of-file",
            "Quit immediately at end-of-file"
        }
    },
    { 'f', &f_optname,
        BOOL, OPT_OFF, &force_open, NULL,
        {
            "Open only regular files",
            "Open even non-regular files",
            NULL
        }
    },
    { 'F', &F__optname,
        BOOL, OPT_OFF, &quit_if_one_screen, NULL,
        {
            "Don't quit if end-of-file on first screen",
            "Quit if end-of-file on first screen",
            NULL
        }
    },
#if HILITE_SEARCH
    { 'g', &g_optname,
        TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL,
        {
            "Don't highlight search matches",
            "Highlight matches for previous search only",
            "Highlight all matches for previous search pattern",
        }
    },
#endif
    { 'h', &h_optname,
        NUMBER, -1, &back_scroll, NULL,
        {
            "Backwards scroll limit: ",
            "Backwards scroll limit is %d lines",
            NULL
        }
    },
    { 'i', &i_optname,
        TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i,
        {
            "Case is significant in searches",
            "Ignore case in searches",
            "Ignore case in searches and in patterns"
        }
    },
    { 'j', &j_optname,
        STRING, 0, NULL, opt_j,
        {
            "Target line: ",
            "0123456789.-",
            NULL
        }
    },
    { 'J', &J__optname,
        BOOL|REPAINT, OPT_OFF, &status_col, NULL,
        {
            "Don't display a status column",
            "Display a status column",
            NULL
        }
    },
#if USERFILE
    { 'k', &k_optname,
        STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k,
        { NULL, NULL, NULL }
    },
#if HAVE_LESSKEYSRC
    { OLETTER_NONE, &ks_optname,
        STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_ks,
        { NULL, NULL, NULL }
    },
#endif /* HAVE_LESSKEYSRC */
#endif
    { 'K', &K__optname,
        BOOL, OPT_OFF, &quit_on_intr, NULL,
        {
            "Interrupt (ctrl-C) returns to prompt",
            "Interrupt (ctrl-C) exits less",
            NULL
        }
    },
    { 'L', &L__optname,
        BOOL, OPT_ON, &use_lessopen, NULL,
        {
            "Don't use the LESSOPEN filter",
            "Use the LESSOPEN filter",
            NULL
        }
    },
    { 'm', &m_optname,
        TRIPLE, OPT_OFF, &pr_type, NULL,
        {
            "Short prompt",
            "Medium prompt",
            "Long prompt"
        }
    },
    { 'n', &n_optname,
        TRIPLE|REPAINT, OPT_ON, &linenums, NULL,
        {
            "Don't use line numbers",
            "Use line numbers",
            "Constantly display line numbers"
        }
    },
#if LOGFILE
    { 'o', &o_optname,
        STRING, 0, NULL, opt_o,
        { "log file: ", NULL, NULL }
    },
    { 'O', &O__optname,
        STRING, 0, NULL, opt__O,
        { "Log file: ", NULL, NULL }
    },
#endif
    { 'p', &p_optname,
        STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p,
        { NULL, NULL, NULL }
    },
    { 'P', &P__optname,
        STRING, 0, NULL, opt__P,
        { "prompt: ", NULL, NULL }
    },
    { 'q', &q_optname,
        TRIPLE, OPT_OFF, &quiet, NULL,
        {
            "Ring the bell for errors AND at eof/bof",
            "Ring the bell for errors but not at eof/bof",
            "Never ring the bell"
        }
    },
    { 'r', &r_optname,
        TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL,
        {
            "Display control characters as ^X",
            "Display control characters directly (not recommended)",
            "Display ANSI sequences directly, other control characters as ^X"
        }
    },
    { 's', &s_optname,
        BOOL|REPAINT, OPT_OFF, &squeeze, NULL,
        {
            "Display all blank lines",
            "Squeeze multiple blank lines",
            NULL
        }
    },
    { 'S', &S__optname,
        BOOL|REPAINT, OPT_OFF, &chopline, NULL,
        {
            "Fold long lines",
            "Chop long lines",
            NULL
        }
    },
#if TAGS
    { 't', &t_optname,
        STRING|NO_QUERY, 0, NULL, opt_t,
        { "tag: ", NULL, NULL }
    },
    { 'T', &T__optname,
        STRING, 0, NULL, opt__T,
        { "tags file: ", NULL, NULL }
    },
#endif
    { 'u', &u_optname,
        TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL,
        {
            "Display underlined text in underline mode",
            "Backspaces cause overstrike",
            "Print backspace as ^H"
        }
    },
    { 'V', &V__optname,
        NOVAR, 0, NULL, opt__V,
        { NULL, NULL, NULL }
    },
    { 'w', &w_optname,
        TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL,
        {
            "Don't highlight first unread line",
            "Highlight first unread line after forward-screen",
            "Highlight first unread line after any forward movement",
        }
    },
    { 'x', &x_optname,
        STRING|REPAINT, 0, NULL, opt_x,
        {
            "Tab stops: ",
            "0123456789,",
            NULL
        }
    },
    { 'X', &X__optname,
        BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL,
        {
            "Send init/deinit strings to terminal",
            "Don't use init/deinit strings",
            NULL
        }
    },
    { 'y', &y_optname,
        NUMBER, -1, &forw_scroll, NULL,
        {
            "Forward scroll limit: ",
            "Forward scroll limit is %d lines",
            NULL
        }
    },
    { 'z', &z_optname,
        NUMBER, -1, &swindow, NULL,
        {
            "Scroll window size: ",
            "Scroll window size is %d lines",
            NULL
        }
    },
    { '"', &quote_optname,
        STRING, 0, NULL, opt_quote,
        { "quotes: ", NULL, NULL }
    },
    { '~', &tilde_optname,
        BOOL|REPAINT, OPT_ON, &twiddle, NULL,
        {
            "Don't show tildes after end of file",
            "Show tildes after end of file",
            NULL
        }
    },
    { '?', &query_optname,
        NOVAR, 0, NULL, opt_query,
        { NULL, NULL, NULL }
    },
    { '#', &pound_optname,
        STRING, 0, NULL, opt_shift,
        {
            "Horizontal shift: ",
            "0123456789.",
            NULL
        }
    },
    { OLETTER_NONE, &keypad_optname,
        BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL,
        {
            "Use keypad mode",
            "Don't use keypad mode",
            NULL
        }
    },
    { OLETTER_NONE, &oldbot_optname,
        BOOL, OPT_OFF, &oldbot, NULL,
        {
            "Use new bottom of screen behavior",
            "Use old bottom of screen behavior",
            NULL
        }
    },
    { OLETTER_NONE, &follow_optname,
        BOOL, FOLLOW_DESC, &follow_mode, NULL,
        {
            "F command follows file descriptor",
            "F command follows file name",
            NULL
        }
    },
    { OLETTER_NONE, &use_backslash_optname,
        BOOL, OPT_OFF, &opt_use_backslash, NULL,
        {
            "Use backslash escaping in command line parameters",
            "Don't use backslash escaping in command line parameters",
            NULL
        }
    },
    { OLETTER_NONE, &rscroll_optname,
        STRING|REPAINT|INIT_HANDLER, 0, NULL, opt_rscroll,
        { "right scroll character: ", NULL, NULL }
    },
    { OLETTER_NONE, &nohistdups_optname,
        BOOL, OPT_OFF, &no_hist_dups, NULL,
        {
            "Allow duplicates in history list",
            "Remove duplicates from history list",
            NULL
        }
    },
    { OLETTER_NONE, &mousecap_optname,
        TRIPLE, OPT_OFF, &mousecap, opt_mousecap,
        {
            "Ignore mouse input",
            "Use the mouse for scrolling",
            "Use the mouse for scrolling (reverse)"
        }
    },
    { OLETTER_NONE, &wheel_lines_optname,
        NUMBER|INIT_HANDLER, 0, &wheel_lines, opt_wheel_lines,
        {
            "Lines to scroll on mouse wheel: ",
            "Scroll %d line(s) on mouse wheel",
            NULL
        }
    },
    { OLETTER_NONE, &perma_marks_optname,
        BOOL, OPT_OFF, &perma_marks, NULL,
        {
            "Don't save marks in history file",
            "Save marks in history file",
            NULL
        }
    },
    { OLETTER_NONE, &linenum_width_optname,
        NUMBER|REPAINT, MIN_LINENUM_WIDTH, &linenum_width, opt_linenum_width,
        {
            "Line number width: ",
            "Line number width is %d chars",
            NULL
        }
    },
    { OLETTER_NONE, &status_col_width_optname,
        NUMBER|REPAINT, 2, &status_col_width, opt_status_col_width,
        {
            "Status column width: ",
            "Status column width is %d chars",
            NULL
        }
    },
    { OLETTER_NONE, &incr_search_optname,
        BOOL, OPT_OFF, &incr_search, NULL,
        {
            "Incremental search is off",
            "Incremental search is on",
            NULL
        }
    },
    { OLETTER_NONE, &use_color_optname,
        BOOL|REPAINT, OPT_OFF, &use_color, NULL,
        {
            "Don't use color",
            "Use color",
            NULL
        }
    },
    { OLETTER_NONE, &want_filesize_optname,
        BOOL|REPAINT, OPT_OFF, &want_filesize, opt_filesize,
        {
            "Don't get size of each file",
            "Get size of each file",
            NULL
        }
    },
    { OLETTER_NONE, &status_line_optname,
        BOOL|REPAINT, OPT_OFF, &status_line, NULL,
        {
            "Don't color each line with its status column color",
            "Color each line with its status column color",
            NULL
        }
    },
    { OLETTER_NONE, &header_optname,
        STRING|REPAINT, 0, NULL, opt_header,
        {
            "Header lines: ",
            NULL,
            NULL
        }
    },
    { OLETTER_NONE, &nonum_headers_optname,
        BOOL|REPAINT, 0, &nonum_headers, NULL,
        {
            "Number header lines",
            "Don't number header lines",
            NULL
        }
    },
    { OLETTER_NONE, &redraw_on_quit_optname,
        BOOL, OPT_OFF, &redraw_on_quit, NULL,
        {
            "Don't redraw screen when quitting",
            "Redraw last screen when quitting",
            NULL
        }
    },
    { OLETTER_NONE, &search_type_optname,
        STRING, 0, NULL, opt_search_type,
        {
            "Search options: ",
            NULL,
            NULL
        }
    },
    { OLETTER_NONE, &exit_F_on_close_optname,
        BOOL, OPT_OFF, &exit_F_on_close, NULL,
        {
            "Don't exit F command when input closes",
            "Exit F command when input closes",
            NULL
        }
    },
#if LESSTEST
    { OLETTER_NONE, &ttyin_name_optname,
        STRING|NO_TOGGLE, 0, NULL, opt_ttyin_name,
        {
            NULL,
            NULL,
            NULL
        }
    },
    { OLETTER_NONE, &rstat_optname,
        STRING|NO_TOGGLE, 0, NULL, opt_rstat,
        {
            NULL,
            NULL,
            NULL
        }
    },
#endif /*LESSTEST*/
    { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
};


/*
 * Initialize each option to its default value.
 */
    public void
init_option(VOID_PARAM)
{
    struct loption *o;
    char *p;

    p = lgetenv("LESS_IS_MORE");
    if (!isnullenv(p))
        less_is_more = 1;

    for (o = option;  o->oletter != '\0';  o++)
    {
        /*
         * Set each variable to its default.
         */
        if (o->ovar != NULL)
            *(o->ovar) = o->odefault;
        if (o->otype & INIT_HANDLER)
            (*(o->ofunc))(INIT, (char *) NULL);
    }
}

/*
 * Find an option in the option table, given its option letter.
 */
    public struct loption *
findopt(c)
    int c;
{
    struct loption *o;

    for (o = option;  o->oletter != '\0';  o++)
    {
        if (o->oletter == c)
            return (o);
        if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c)
            return (o);
    }
    return (NULL);
}

/*
 *
 */
    static int
is_optchar(c)
    char c;
{
    if (ASCII_IS_UPPER(c))
        return 1;
    if (ASCII_IS_LOWER(c))
        return 1;
    if (c == '-')
        return 1;
    return 0;
}

/*
 * Find an option in the option table, given its option name.
 * p_optname is the (possibly partial) name to look for, and
 * is updated to point after the matched name.
 * p_oname if non-NULL is set to point to the full option name.
 */
    public struct loption *
findopt_name(p_optname, p_oname, p_err)
    char **p_optname;
    char **p_oname;
    int *p_err;
{
    char *optname = *p_optname;
    struct loption *o;
    struct optname *oname;
    int len;
    int uppercase;
    struct loption *maxo = NULL;
    struct optname *maxoname = NULL;
    int maxlen = 0;
    int ambig = 0;
    int exact = 0;

    /*
     * Check all options.
     */
    for (o = option;  o->oletter != '\0';  o++)
    {
        /*
         * Check all names for this option.
         */
        for (oname = o->onames;  oname != NULL;  oname = oname->onext)
        {
            /*
             * Try normal match first (uppercase == 0),
             * then, then if it's a TRIPLE option,
             * try uppercase match (uppercase == 1).
             */
            for (uppercase = 0;  uppercase <= 1;  uppercase++)
            {
                len = sprefix(optname, oname->oname, uppercase);
                if (len <= 0 || is_optchar(optname[len]))
                {
                    /*
                     * We didn't use all of the option name.
                     */
                    continue;
                }
                if (!exact && len == maxlen)
                    /*
                     * Already had a partial match,
                     * and now there's another one that
                     * matches the same length.
                     */
                    ambig = 1;
                else if (len > maxlen)
                {
                    /*
                     * Found a better match than
                     * the one we had.
                     */
                    maxo = o;
                    maxoname = oname;
                    maxlen = len;
                    ambig = 0;
                    exact = (len == (int)strlen(oname->oname));
                }
                if (!(o->otype & TRIPLE))
                    break;
            }
        }
    }
    if (ambig)
    {
        /*
         * Name matched more than one option.
         */
        if (p_err != NULL)
            *p_err = OPT_AMBIG;
        return (NULL);
    }
    *p_optname = optname + maxlen;
    if (p_oname != NULL)
        *p_oname = maxoname == NULL ? NULL : maxoname->oname;
    return (maxo);
}