root/src/noitedit/readline.c

/*      $NetBSD: readline.c,v 1.19 2001/01/10 08:10:45 jdolecek Exp $   */

/*-
 * Copyright (c) 1997 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jaromir Dolecek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the NetBSD
 *      Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "noitedit/compat.h"
#if !defined(lint) && !defined(SCCSID)
__RCSID("$NetBSD: readline.c,v 1.19 2001/01/10 08:10:45 jdolecek Exp $");
#endif /* not lint && not SCCSID */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <stdio.h>
#if !_MSC_VER
#include <dirent.h>
#endif
#include <string.h>
#if HAVE_PWD_H
#include <pwd.h>
#endif
#include <ctype.h>
#include <stdlib.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_ALLOCA_H
#include <alloca.h>
#endif
#include <limits.h>
#include "noitedit/histedit.h"
#include "noitedit/readline/readline.h"
#include "noitedit/sys.h"
#include "noitedit/el.h"
#include "noitedit/fcns.h"              /* for EL_NUM_FCNS */

extern int el_internal_read_char(EditLine *el, char *cp);
extern int el_internal_read_getcmd(EditLine *el, el_action_t *cmdnum, char *ch, int nonblock);
extern int el_gets_dispatch(EditLine *el, el_action_t cmdnum, char ch, int *num);

/* for rl_complete() */
#define TAB             '\r'

/* see comment at the #ifdef for sense of this */
#define GDB_411_HACK

/* readline compatibility stuff - look at readline sources/documentation */
/* to see what these variables mean */
const char *rl_library_version = "EditLine wrapper";
char *rl_readline_name = "";
FILE *rl_instream = NULL;
FILE *rl_outstream = NULL;
int rl_point = 0;
int rl_end = 0;
char *rl_line_buffer = NULL;

int history_base = 1;           /* probably never subject to change */
int history_length = 0;
int max_input_history = 0;
char history_expansion_char = '!';
char history_subst_char = '^';
char *history_no_expand_chars = " \t\n=(";
Function *history_inhibit_expansion_function = NULL;

int rl_inhibit_completion = 0;
int rl_attempted_completion_over = 0;
char *rl_basic_word_break_characters = " \t\n\"\\'`@$><=;|&{(";
char *rl_completer_word_break_characters = NULL;
char *rl_completer_quote_characters = NULL;
CPFunction *rl_completion_entry_function = NULL;
CPPFunction *rl_attempted_completion_function = NULL;

/*
 * This is set to character indicating type of completion being done by
 * rl_complete_internal(); this is available for application completion
 * functions.
 */
int rl_completion_type = 0;

/*
 * If more than this number of items results from query for possible
 * completions, we ask user if they are sure to really display the list.
 */
int rl_completion_query_items = 100;

/*
 * List of characters which are word break characters, but should be left
 * in the parsed text when it is passed to the completion function.
 * Shell uses this to help determine what kind of completing to do.
 */
char *rl_special_prefixes = (char *)NULL;

/*
 * This is the character appended to the completed words if at the end of
 * the line. Default is ' ' (a space).
 */
int rl_completion_append_character = ' ';

/* stuff below is used internally by libedit for readline emulation */

/* if not zero, non-unique completions always show list of possible matches */
static int _rl_complete_show_all = 0;

static History *h = NULL;
static EditLine *e = NULL;
static int el_rl_complete_cmdnum = 0;

/* internal functions */
static unsigned char     _el_rl_complete(EditLine *, int);
static char             *_get_prompt(EditLine *);
static HIST_ENTRY       *_move_history(int);
static int               _history_search_gen(const char *, int, int);
static int               _history_expand_command(const char *, size_t, char **);
static char             *_rl_compat_sub(const char *, const char *,
                            const char *, int);
static int               rl_complete_internal(int);
static int               _rl_qsort_string_compare(const void *, const void *);

/*
 * needed for prompt switching in readline()
 */
static char *el_rl_prompt = NULL;


/* ARGSUSED */
static char *
_get_prompt(EditLine *el)
{
        return (el_rl_prompt);
}


/*
 * generic function for moving around history
 */
static HIST_ENTRY *
_move_history(int op)
{
        HistEvent ev;
        static HIST_ENTRY rl_he;

        if (history(h, &ev, op) != 0)
                return (HIST_ENTRY *) NULL;

        rl_he.line = ev.str;
        rl_he.data = "";

        return (&rl_he);
}


/*
 * READLINE compatibility stuff
 */

/*
 * initialize rl compat stuff
 */
int
rl_initialize(void)
{
        HistEvent ev;
        const LineInfo *li;
        int i;
        int editmode = 1;
        struct termios t;

        if (e != NULL)
                el_end(e);
        if (h != NULL)
                history_end(h);

        if (!rl_instream)
                rl_instream = stdin;
        if (!rl_outstream)
                rl_outstream = stdout;

        /*
         * See if we don't really want to run the editor
         */
        if (tcgetattr(fileno(rl_instream), &t) != -1 && (t.c_lflag & ECHO) == 0)
                editmode = 0;

        e = el_init(rl_readline_name,
                    fileno(rl_instream), NULL,
                    fileno(rl_outstream), NULL,
                    fileno(stderr), NULL);

        if (!editmode)
                el_set(e, EL_EDITMODE, 0);

        h = history_init();
        if (!e || !h)
                return (-1);

        history(h, &ev, H_SETSIZE, INT_MAX);    /* unlimited */
        history_length = 0;
        max_input_history = INT_MAX;
        el_set(e, EL_HIST, history, h);

        /* for proper prompt printing in readline() */
        el_rl_prompt = strdup("");
        el_set(e, EL_PROMPT, _get_prompt);
        el_set(e, EL_SIGNAL, 1);

        /* set default mode to "emacs"-style and read setting afterwards */
        /* so this can be overriden */
        el_set(e, EL_EDITOR, "emacs");

        /*
         * Word completition - this has to go AFTER rebinding keys
         * to emacs-style.
         */
        el_set(e, EL_ADDFN, "rl_complete",
            "ReadLine compatible completion function",
            _el_rl_complete);
        el_set(e, EL_BIND, "^I", "rl_complete", NULL);

        /*
         * Find out where the rl_complete function was added; this is
         * used later to detect that lastcmd was also rl_complete.
         */
        for(i=EL_NUM_FCNS; i < e->el_map.nfunc; i++) {
                if (e->el_map.func[i] == _el_rl_complete) {
                        el_rl_complete_cmdnum = i;
                        break;
                }
        }
                
        /* read settings from configuration file */
        el_source(e, NULL);

        /*
         * Unfortunately, some applications really do use rl_point
         * and rl_line_buffer directly.
         */
        li = el_line(e);
        /* LINTED const cast */
        rl_line_buffer = (char *) li->buffer;
        rl_point = rl_end = 0;

        return (0);
}

EditLine *el_readline_get_e(void)
{
        if (e == NULL || h == NULL)
                rl_initialize();
        return e;
}

static ec_rl_line_consumer_func ec_consumer = NULL;

int ec_rl_setup_event_driven_mode(const char *prompt, ec_rl_line_consumer_func consumer)
{
#ifdef FIONREAD
        c_macro_t *ma;
#endif /* FIONREAD */

        if (e == NULL || h == NULL)
                rl_initialize();

        ec_consumer = consumer;

        /* update prompt accordingly to what has been passed */
        if (!prompt)
                prompt = "";
        if (strcmp(el_rl_prompt, prompt) != 0) {
                free(el_rl_prompt);
                el_rl_prompt = strdup(prompt);
        }

        if (e->el_flags & HANDLE_SIGNALS)
                sig_set(e);

        if (e->el_flags & NO_TTY) {
#ifdef _WIN32
                printf("%s", e->el_prompt.p_func(e));
#endif
                e->el_line.cursor = e->el_line.buffer;
                return 1;
        }
        re_clear_display(e);
        ch_reset(e);

#ifdef FIONREAD
        ma = &e->el_chared.c_macro;
        if (e->el_tty.t_mode == EX_IO && ma->level < 0) {
                long chrs = 0;

                (void) ioctl(e->el_infd, FIONREAD, (ioctl_t) & chrs);
                if (chrs == 0) {
                        if (tty_rawmode(e) < 0) {
                                return 0;
                        }
                }
        }
#endif /* FIONREAD */
        if (tty_rawmode(e) < 0) {
                return 0;
        }

        re_refresh(e); /* renders the prompt */
        if (e->el_flags & EDIT_DISABLED) {
                term__flush();
                return 1;
        }
        return 1;
}

static void call_consumer(int eof)
{
        tty_cookedmode(e);
        term__flush();
        if (e->el_flags & HANDLE_SIGNALS)
                sig_clr(e);
        ec_consumer(eof ? NULL : e->el_line.buffer);
}

int ec_rl_finish_event_driven_mode(void)
{
        tty_cookedmode(e);
        term__flush();
        if (e->el_flags & HANDLE_SIGNALS)
                sig_clr(e);
        return 0;
}

int ec_rl_input_is_ready_to_read(void)
{
        el_action_t cmdnum = 0;
        int num;                /* how many chars we have read at NL */
        char ch;

        if ((e->el_flags & NO_TTY) || (e->el_flags & EDIT_DISABLED)) {
                size_t idx;
                char *cp = e->el_line.cursor;

                num = el_internal_read_char(e, cp);
                if (num == 1) {
                        /* make sure there is space for next character */
                        if (cp + 1 >= e->el_line.limit) {
                                idx = (cp - e->el_line.buffer);
                                if (!ch_enlargebufs(e, 2))
                                        goto gotline;
                                cp = &e->el_line.buffer[idx];
                        }
                        cp++;
                        e->el_line.cursor = e->el_line.lastchar = cp;
                        *cp = '\0';
                        if (cp[-1] == '\r' || cp[-1] == '\n') {
                                num = 1;
                                goto gotline;
                        }
                } else if (num <= 0) {
                        call_consumer(1);
                        return 1;
                }
                return 0;
        }

        num = el_internal_read_getcmd(e, &cmdnum, &ch, 0);
        if (num == -1) {
                if (cmdnum == ED_UNASSIGNED)
                        return 0;
                el_gets_dispatch(e, cmdnum, ch, &num);
                if (num == -1)
                        return 0;
        }

gotline:
        call_consumer(num == 0);
        return 1;
}

/*
 * read one line from input stream and return it, chomping
 * trailing newline (if there is any)
 */
char *
readline(const char *prompt)
{
        int count;
        const char *ret;
        HistEvent ev;

        if (e == NULL || h == NULL)
                rl_initialize();

        /* update prompt accordingly to what has been passed */
        if (!prompt)
                prompt = "";
        if (strcmp(el_rl_prompt, prompt) != 0) {
                free(el_rl_prompt);
                el_rl_prompt = strdup(prompt);
        }
        /* get one line from input stream */
        ret = el_gets(e, &count);

        if (ret && count > 0) {
                char *foo;
                int lastidx;

                foo = strdup(ret);
                lastidx = count - 1;
                if (foo[lastidx] == '\n')
                        foo[lastidx] = '\0';

                ret = foo;
        } else
                ret = NULL;

        history(h, &ev, H_GETSIZE);
        history_length = ev.num;

        /* LINTED const cast */
        return (char *) ret;
}

/*
 * history functions
 */

/*
 * is normally called before application starts to use
 * history expansion functions
 */
void
using_history(void)
{
        if (h == NULL || e == NULL)
                rl_initialize();
}


/*
 * substitute ``what'' with ``with'', returning resulting string; if
 * globally == 1, substitutes all occurences of what, otherwise only the
 * first one
 */
static char *
_rl_compat_sub(const char *str, const char *what, const char *with,
    int globally)
{
        char *result;
        const char *temp, *new;
        int len, with_len, what_len, add;
        size_t size, i;

        result = malloc((size = 16));
        temp = str;
        with_len = strlen(with);
        what_len = strlen(what);
        len = 0;
        do {
                new = strstr(temp, what);
                if (new) {
                        i = new - temp;
                        add = i + with_len;
                        if (i + add + 1 >= size) {
                                size += add + 1;
                                result = realloc(result, size);
                        }
                        (void) strncpy(&result[len], temp, i);
                        len += i;
                        (void) strcpy(&result[len], with);      /* safe */
                        len += with_len;
                        temp = new + what_len;
                } else {
                        add = strlen(temp);
                        if (len + add + 1 >= size) {
                                size += add + 1;
                                result = realloc(result, size);
                        }
                        (void) strcpy(&result[len], temp);      /* safe */
                        len += add;
                        temp = NULL;
                }
        } while (temp && globally);
        result[len] = '\0';

        return (result);
}


/*
 * the real function doing history expansion - takes as argument command
 * to do and data upon which the command should be executed
 * does expansion the way I've understood readline documentation
 * word designator ``%'' isn't supported (yet ?)
 *
 * returns 0 if data was not modified, 1 if it was and 2 if the string
 * should be only printed and not executed; in case of error,
 * returns -1 and *result points to NULL
 * it's callers responsibility to free() string returned in *result
 */
static int
_history_expand_command(const char *command, size_t cmdlen, char **result)
{
        char **arr, *tempcmd, *line, *search = NULL, *cmd;
        const char *event_data = NULL;
        static char *from = NULL, *to = NULL;
        int start = -1, end = -1, max, i, idx;
        int h_on = 0, t_on = 0, r_on = 0, e_on = 0, p_on = 0, g_on = 0;
        int event_num = 0, retval;
        size_t cmdsize;

        *result = NULL;

        cmd = alloca(cmdlen + 1);
        (void) strncpy(cmd, command, cmdlen);
        cmd[cmdlen] = 0;

        idx = 1;
        /* find out which event to take */
        if (cmd[idx] == history_expansion_char) {
                event_num = history_length;
                idx++;
        } else {
                int off, num;
                size_t len;
                off = idx;
                while (cmd[off] && !strchr(":^$*-%", cmd[off]))
                        off++;
                num = atoi(&cmd[idx]);
                if (num != 0) {
                        event_num = num;
                        if (num < 0)
                                event_num += history_length + 1;
                } else {
                        int prefix = 1, curr_num;
                        HistEvent ev;

                        len = off - idx;
                        if (cmd[idx] == '?') {
                                idx++, len--;
                                if (cmd[off - 1] == '?')
                                        len--;
                                else if (cmd[off] != '\n' && cmd[off] != '\0')
                                        return (-1);
                                prefix = 0;
                        }
                        search = alloca(len + 1);
                        (void) strncpy(search, &cmd[idx], len);
                        search[len] = '\0';

                        if (history(h, &ev, H_CURR) != 0)
                                return (-1);
                        curr_num = ev.num;

                        if (prefix)
                                retval = history_search_prefix(search, -1);
                        else
                                retval = history_search(search, -1);

                        if (retval == -1) {
                                fprintf(rl_outstream, "%s: Event not found\n",
                                    search);
                                return (-1);
                        }
                        if (history(h, &ev, H_CURR) != 0)
                                return (-1);
                        event_data = ev.str;

                        /* roll back to original position */
                        history(h, &ev, H_NEXT_EVENT, curr_num);
                }
                idx = off;
        }

        if (!event_data && event_num >= 0) {
                HIST_ENTRY *rl_he;
                rl_he = history_get(event_num);
                if (!rl_he)
                        return (0);
                event_data = rl_he->line;
        } else
                return (-1);

        if (cmd[idx] != ':')
                return (-1);
        cmd += idx + 1;

        /* recognize cmd */
        if (*cmd == '^')
                start = end = 1, cmd++;
        else if (*cmd == '$')
                start = end = -1, cmd++;
        else if (*cmd == '*')
                start = 1, end = -1, cmd++;
        else if (isdigit((unsigned char) *cmd)) {
                const char *temp;
                int shifted = 0;

                start = atoi(cmd);
                temp = cmd;
                for (; isdigit((unsigned char) *cmd); cmd++);
                if (temp != cmd)
                        shifted = 1;
                if (shifted && *cmd == '-') {
                        if (!isdigit((unsigned char) *(cmd + 1)))
                                end = -2;
                        else {
                                end = atoi(cmd + 1);
                                for (; isdigit((unsigned char) *cmd); cmd++);
                        }
                } else if (shifted && *cmd == '*')
                        end = -1, cmd++;
                else if (shifted)
                        end = start;
        }
        if (*cmd == ':')
                cmd++;

        line = strdup(event_data);
        for (; *cmd; cmd++) {
                if (*cmd == ':')
                        continue;
                else if (*cmd == 'h')
                        h_on = 1 | g_on, g_on = 0;
                else if (*cmd == 't')
                        t_on = 1 | g_on, g_on = 0;
                else if (*cmd == 'r')
                        r_on = 1 | g_on, g_on = 0;
                else if (*cmd == 'e')
                        e_on = 1 | g_on, g_on = 0;
                else if (*cmd == 'p')
                        p_on = 1 | g_on, g_on = 0;
                else if (*cmd == 'g')
                        g_on = 2;
                else if (*cmd == 's' || *cmd == '&') {
                        char *what, *with, delim;
                        int len, from_len;
                        size_t size;

                        if (*cmd == '&' && (from == NULL || to == NULL))
                                continue;
                        else if (*cmd == 's') {
                                delim = *(++cmd), cmd++;
                                size = 16;
                                what = realloc(from, size);
                                len = 0;
                                for (; *cmd && *cmd != delim; cmd++) {
                                        if (*cmd == '\\'
                                            && *(cmd + 1) == delim)
                                                cmd++;
                                        if (len >= size)
                                                what = realloc(what,
                                                    (size <<= 1));
                                        what[len++] = *cmd;
                                }
                                what[len] = '\0';
                                from = what;
                                if (*what == '\0') {
                                        free(what);
                                        if (search)
                                                from = strdup(search);
                                        else {
                                                from = NULL;
                                                return (-1);
                                        }
                                }
                                cmd++;  /* shift after delim */
                                if (!*cmd)
                                        continue;

                                size = 16;
                                with = realloc(to, size);
                                len = 0;
                                from_len = strlen(from);
                                for (; *cmd && *cmd != delim; cmd++) {
                                        if (len + from_len + 1 >= size) {
                                                size += from_len + 1;
                                                with = realloc(with, size);
                                        }
                                        if (*cmd == '&') {
                                                /* safe */
                                                (void) strcpy(&with[len], from);
                                                len += from_len;
                                                continue;
                                        }
                                        if (*cmd == '\\'
                                            && (*(cmd + 1) == delim
                                                || *(cmd + 1) == '&'))
                                                cmd++;
                                        with[len++] = *cmd;
                                }
                                with[len] = '\0';
                                to = with;

                                tempcmd = _rl_compat_sub(line, from, to,
                                    (g_on) ? 1 : 0);
                                free(line);
                                line = tempcmd;
                                g_on = 0;
                        }
                }
        }

        arr = history_tokenize(line);
        free(line);             /* no more needed */
        if (arr && *arr == NULL)
                free(arr), arr = NULL;
        if (!arr)
                return (-1);

        /* find out max valid idx to array of array */
        max = 0;
        for (i = 0; arr[i]; i++)
                max++;
        max--;

        /* set boundaries to something relevant */
        if (start < 0)
                start = 1;
        if (end < 0)
                end = max - ((end < -1) ? 1 : 0);

        /* check boundaries ... */
        if (start > max || end > max || start > end)
                return (-1);

        for (i = 0; i <= max; i++) {
                char *temp;
                if (h_on && (i == 1 || h_on > 1) &&
                    (temp = strrchr(arr[i], '/')))
                        *(temp + 1) = '\0';
                if (t_on && (i == 1 || t_on > 1) &&
                    (temp = strrchr(arr[i], '/')))
                        (void) strcpy(arr[i], temp + 1);
                if (r_on && (i == 1 || r_on > 1) &&
                    (temp = strrchr(arr[i], '.')))
                        *temp = '\0';
                if (e_on && (i == 1 || e_on > 1) &&
                    (temp = strrchr(arr[i], '.')))
                        (void) strcpy(arr[i], temp);
        }

        cmdsize = 1, cmdlen = 0;
        tempcmd = malloc(cmdsize);
        for (i = start; start <= i && i <= end; i++) {
                int arr_len;

                arr_len = strlen(arr[i]);
                if (cmdlen + arr_len + 1 >= cmdsize) {
                        cmdsize += arr_len + 1;
                        tempcmd = realloc(tempcmd, cmdsize);
                }
                (void) strcpy(&tempcmd[cmdlen], arr[i]);        /* safe */
                cmdlen += arr_len;
                tempcmd[cmdlen++] = ' ';        /* add a space */
        }
        while (cmdlen > 0 && isspace((unsigned char) tempcmd[cmdlen - 1]))
                cmdlen--;
        tempcmd[cmdlen] = '\0';

        *result = tempcmd;

        for (i = 0; i <= max; i++)
                free(arr[i]);
        free(arr), arr = (char **) NULL;
        return (p_on) ? 2 : 1;
}


/*
 * csh-style history expansion
 */
int
history_expand(char *str, char **output)
{
        int i, retval = 0, idx;
        size_t size;
        char *temp, *result;

        if (h == NULL || e == NULL)
                rl_initialize();

        *output = strdup(str);  /* do it early */

        if (str[0] == history_subst_char) {
                /* ^foo^foo2^ is equivalent to !!:s^foo^foo2^ */
                temp = alloca(4 + strlen(str) + 1);
                temp[0] = temp[1] = history_expansion_char;
                temp[2] = ':';
                temp[3] = 's';
                (void) strcpy(temp + 4, str);
                str = temp;
        }
#define ADD_STRING(what, len)                                           \
        {                                                               \
                if (idx + len + 1 > size)                               \
                        result = realloc(result, (size += len + 1));    \
                (void)strncpy(&result[idx], what, len);                 \
                idx += len;                                             \
                result[idx] = '\0';                                     \
        }

        result = NULL;
        size = idx = 0;
        for (i = 0; str[i];) {
                int start, j, loop_again;
                size_t len;

                loop_again = 1;
                start = j = i;
loop:
                for (; str[j]; j++) {
                        if (str[j] == '\\' &&
                            str[j + 1] == history_expansion_char) {
                                (void) strcpy(&str[j], &str[j + 1]);
                                continue;
                        }
                        if (!loop_again) {
                                if (str[j] == '?') {
                                        while (str[j] && str[++j] != '?');
                                        if (str[j] == '?')
                                                j++;
                                } else if (isspace((unsigned char) str[j]))
                                        break;
                        }
                        if (str[j] == history_expansion_char
                            && !strchr(history_no_expand_chars, str[j + 1])
                            && (!history_inhibit_expansion_function ||
                            (*history_inhibit_expansion_function)(str, j) == 0))
                                break;
                }

                if (str[j] && str[j + 1] != '#' && loop_again) {
                        i = j;
                        j++;
                        if (str[j] == history_expansion_char)
                                j++;
                        loop_again = 0;
                        goto loop;
                }
                len = i - start;
                temp = &str[start];
                ADD_STRING(temp, len);

                if (str[i] == '\0' || str[i] != history_expansion_char
                    || str[i + 1] == '#') {
                        len = j - i;
                        temp = &str[i];
                        ADD_STRING(temp, len);
                        if (start == 0)
                                retval = 0;
                        else
                                retval = 1;
                        break;
                }
                retval = _history_expand_command(&str[i], (size_t) (j - i),
                    &temp);
                if (retval != -1) {
                        len = strlen(temp);
                        ADD_STRING(temp, len);
                }
                i = j;
        }                       /* for(i ...) */

        if (retval == 2) {
                add_history(temp);
#ifdef GDB_411_HACK
                /* gdb 4.11 has been shipped with readline, where */
                /* history_expand() returned -1 when the line     */
                /* should not be executed; in readline 2.1+       */
                /* it should return 2 in such a case              */
                retval = -1;
#endif
        }
        free(*output);
        *output = result;

        return (retval);
}


/*
 * Parse the string into individual tokens, similarily to how shell would do it.
 */
char **
history_tokenize(const char *str)
{
        int size = 1, result_idx = 0, i, start;
        size_t len;
        char **result = NULL, *temp, delim = '\0';

        for (i = 0; str[i]; i++) {
                while (isspace((unsigned char) str[i]))
                        i++;
                start = i;
                for (; str[i]; i++) {
                        if (str[i] == '\\') {
                                if (str[i+1] != '\0')
                                        i++;
                        } else if (str[i] == delim)
                                delim = '\0';
                        else if (!delim &&
                                    (isspace((unsigned char) str[i]) ||
                                strchr("()<>;&|$", str[i])))
                                break;
                        else if (!delim && strchr("'`\"", str[i]))
                                delim = str[i];
                }

                if (result_idx + 2 >= size) {
                        size <<= 1;
                        result = realloc(result, size * sizeof(char *));
                }
                len = i - start;
                temp = malloc(len + 1);
                (void) strncpy(temp, &str[start], len);
                temp[len] = '\0';
                result[result_idx++] = temp;
                result[result_idx] = NULL;
        }

        return (result);
}


/*
 * limit size of history record to ``max'' events
 */
void
stifle_history(int max)
{
        HistEvent ev;

        if (h == NULL || e == NULL)
                rl_initialize();

        if (history(h, &ev, H_SETSIZE, max) == 0)
                max_input_history = max;
}


/*
 * "unlimit" size of history - set the limit to maximum allowed int value
 */
int
unstifle_history(void)
{
        HistEvent ev;
        int omax;

        history(h, &ev, H_SETSIZE, INT_MAX);
        omax = max_input_history;
        max_input_history = INT_MAX;
        return (omax);          /* some value _must_ be returned */
}


int
history_is_stifled(void)
{

        /* cannot return true answer */
        return (max_input_history != INT_MAX);
}


/*
 * read history from a file given
 */
int
read_history(const char *filename)
{
        HistEvent ev;

        if (h == NULL || e == NULL)
                rl_initialize();
        return (history(h, &ev, H_LOAD, filename));
}


/*
 * write history to a file given
 */
int
write_history(const char *filename)
{
        HistEvent ev;

        if (h == NULL || e == NULL)
                rl_initialize();
        return (history(h, &ev, H_SAVE, filename));
}


/*
 * returns history ``num''th event
 *
 * returned pointer points to static variable
 */
HIST_ENTRY *
history_get(int num)
{
        static HIST_ENTRY she;
        HistEvent ev;
        int i = 1, curr_num;

        if (h == NULL || e == NULL)
                rl_initialize();

        /* rewind to beginning */
        if (history(h, &ev, H_CURR) != 0)
                return (NULL);
        curr_num = ev.num;
        if (history(h, &ev, H_LAST) != 0)
                return (NULL);  /* error */
        while (i < num && history(h, &ev, H_PREV) == 0)
                i++;
        if (i != num)
                return (NULL);  /* not so many entries */

        she.line = ev.str;
        she.data = NULL;

        /* rewind history to the same event it was before */
        (void) history(h, &ev, H_FIRST);
        (void) history(h, &ev, H_NEXT_EVENT, curr_num);

        return (&she);
}


/*
 * add the line to history table
 */
int
add_history(const char *line)
{
        HistEvent ev;

        if (h == NULL || e == NULL)
                rl_initialize();

        (void) history(h, &ev, H_ENTER, line);
        if (history(h, &ev, H_GETSIZE) == 0)
                history_length = ev.num;

        return (!(history_length > 0)); /* return 0 if all is okay */
}


/*
 * clear the history list - delete all entries
 */
void
clear_history(void)
{
        HistEvent ev;

        history(h, &ev, H_CLEAR);
}


/*
 * returns offset of the current history event
 */
int
where_history(void)
{
        HistEvent ev;
        int curr_num, off;

        if (history(h, &ev, H_CURR) != 0)
                return (0);
        curr_num = ev.num;

        history(h, &ev, H_FIRST);
        off = 1;
        while (ev.num != curr_num && history(h, &ev, H_NEXT) == 0)
                off++;

        return (off);
}


/*
 * returns current history event or NULL if there is no such event
 */
HIST_ENTRY *
current_history(void)
{

        return (_move_history(H_CURR));
}


/*
 * returns total number of bytes history events' data are using
 */
int
history_total_bytes(void)
{
        HistEvent ev;
        int curr_num, size;

        if (history(h, &ev, H_CURR) != 0)
                return (-1);
        curr_num = ev.num;

        history(h, &ev, H_FIRST);
        size = 0;
        do
                size += strlen(ev.str);
        while (history(h, &ev, H_NEXT) == 0);

        /* get to the same position as before */
        history(h, &ev, H_PREV_EVENT, curr_num);

        return (size);
}


/*
 * sets the position in the history list to ``pos''
 */
int
history_set_pos(int pos)
{
        HistEvent ev;
        int off, curr_num;

        if (pos > history_length || pos < 0)
                return (-1);

        history(h, &ev, H_CURR);
        curr_num = ev.num;
        history(h, &ev, H_FIRST);
        off = 0;
        while (off < pos && history(h, &ev, H_NEXT) == 0)
                off++;

        if (off != pos) {       /* do a rollback in case of error */
                history(h, &ev, H_FIRST);
                history(h, &ev, H_NEXT_EVENT, curr_num);
                return (-1);
        }
        return (0);
}


/*
 * returns previous event in history and shifts pointer accordingly
 */
HIST_ENTRY *
previous_history(void)
{

        return (_move_history(H_PREV));
}


/*
 * returns next event in history and shifts pointer accordingly
 */
HIST_ENTRY *
next_history(void)
{

        return (_move_history(H_NEXT));
}


/*
 * generic history search function
 */
static int
_history_search_gen(const char *str, int direction, int pos)
{
        HistEvent ev;
        const char *strp;
        int curr_num;

        if (history(h, &ev, H_CURR) != 0)
                return (-1);
        curr_num = ev.num;

        for (;;) {
                strp = strstr(ev.str, str);
                if (strp && (pos < 0 || &ev.str[pos] == strp))
                        return (int) (strp - ev.str);
                if (history(h, &ev, direction < 0 ? H_PREV : H_NEXT) != 0)
                        break;
        }

        history(h, &ev, direction < 0 ? H_NEXT_EVENT : H_PREV_EVENT, curr_num);

        return (-1);
}


/*
 * searches for first history event containing the str
 */
int
history_search(const char *str, int direction)
{

        return (_history_search_gen(str, direction, -1));
}


/*
 * searches for first history event beginning with str
 */
int
history_search_prefix(const char *str, int direction)
{

        return (_history_search_gen(str, direction, 0));
}


/*
 * search for event in history containing str, starting at offset
 * abs(pos); continue backward, if pos<0, forward otherwise
 */
/* ARGSUSED */
int
history_search_pos(const char *str, int direction, int pos)
{
        HistEvent ev;
        int curr_num, off;

        off = (pos > 0) ? pos : -pos;
        pos = (pos > 0) ? 1 : -1;

        if (history(h, &ev, H_CURR) != 0)
                return (-1);
        curr_num = ev.num;

        if (history_set_pos(off) != 0 || history(h, &ev, H_CURR) != 0)
                return (-1);


        for (;;) {
                if (strstr(ev.str, str))
                        return (off);
                if (history(h, &ev, (pos < 0) ? H_PREV : H_NEXT) != 0)
                        break;
        }

        /* set "current" pointer back to previous state */
        history(h, &ev, (pos < 0) ? H_NEXT_EVENT : H_PREV_EVENT, curr_num);

        return (-1);
}


/********************************/
/* completition functions       */

/*
 * does tilde expansion of strings of type ``~user/foo''
 * if ``user'' isn't valid user name or ``txt'' doesn't start
 * w/ '~', returns pointer to strdup()ed copy of ``txt''
 *
 * it's callers's responsibility to free() returned string
 */
char *
tilde_expand(char *txt)
{
        struct passwd *pass;
        char *temp;
        size_t len = 0;

        if (txt[0] != '~')
                return (strdup(txt));

        temp = strchr(txt + 1, '/');
        if (temp == NULL)
                temp = strdup(txt + 1);
        else {
                len = temp - txt + 1;   /* text until string after slash */
                temp = malloc(len);
                (void) strncpy(temp, txt + 1, len - 2);
                temp[len - 2] = '\0';
        }
#if _MSC_VER
        free(temp);             /* value no more needed */
        return strdup(txt);
#else
        pass = getpwnam(temp);
        free(temp);             /* value no more needed */
        if (pass == NULL)
                return (strdup(txt));

        /* update pointer txt to point at string immedially following */
        /* first slash */
        txt += len;

        temp = malloc(strlen(pass->pw_dir) + 1 + strlen(txt) + 1);
        (void) sprintf(temp, "%s/%s", pass->pw_dir, txt);

        return (temp);
#endif
}


/*
 * return first found file name starting by the ``text'' or NULL if no
 * such file can be found
 * value of ``state'' is ignored
 *
 * it's caller's responsibility to free returned string
 */
char *
filename_completion_function(const char *text, int state)
{
#if _MSC_VER
        return NULL;
#else
        static DIR *dir = NULL;
        static char *filename = NULL, *dirname = NULL;
        static size_t filename_len = 0;
        struct dirent *entry;
        char *temp;
        size_t len;

        if (state == 0 || dir == NULL) {
                if (dir != NULL) {
                        closedir(dir);
                        dir = NULL;
                }
                temp = strrchr(text, '/');
                if (temp) {
                        temp++;
                        filename = realloc(filename, strlen(temp) + 1);
                        (void) strcpy(filename, temp);
                        len = temp - text;      /* including last slash */
                        dirname = realloc(dirname, len + 1);
                        (void) strncpy(dirname, text, len);
                        dirname[len] = '\0';
                } else {
                        filename = strdup(text);
                        dirname = NULL;
                }

                /* support for ``~user'' syntax */
                if (dirname && *dirname == '~') {
                        temp = tilde_expand(dirname);
                        dirname = realloc(dirname, strlen(temp) + 1);
                        (void) strcpy(dirname, temp);   /* safe */
                        free(temp);     /* no longer needed */
                }
                /* will be used in cycle */
                filename_len = strlen(filename);
                if (filename_len == 0)
                        return (NULL);  /* no expansion possible */

                dir = opendir(dirname ? dirname : ".");
                if (!dir)
                        return (NULL);  /* cannot open the directory */
        }
        /* find the match */
        while ((entry = readdir(dir)) != NULL) {
                /* otherwise, get first entry where first */
                /* filename_len characters are equal      */
                if (entry->d_name[0] == filename[0]
#if defined(__SVR4) || defined(__linux__)
                    && strlen(entry->d_name) >= filename_len
#else
                    && entry->d_namlen >= filename_len
#endif
                    && strncmp(entry->d_name, filename,
                        filename_len) == 0)
                        break;
        }

        if (entry) {            /* match found */

                struct stat stbuf;
#if defined(__SVR4) || defined(__linux__)
                len = strlen(entry->d_name) +
#else
                len = entry->d_namlen +
#endif
                    ((dirname) ? strlen(dirname) : 0) + 1 + 1;
                temp = malloc(len);
                (void) sprintf(temp, "%s%s",
                    dirname ? dirname : "", entry->d_name);     /* safe */

                /* test, if it's directory */
                if (stat(temp, &stbuf) == 0 && S_ISDIR(stbuf.st_mode))
                        strcat(temp, "/");      /* safe */
        } else
                temp = NULL;

        return (temp);
#endif
}


/*
 * a completion generator for usernames; returns _first_ username
 * which starts with supplied text
 * text contains a partial username preceded by random character
 * (usually '~'); state is ignored
 * it's callers responsibility to free returned value
 */
char *
username_completion_function(const char *text, int state)
{
#if _MSC_VER
        return NULL;
#else
        struct passwd *pwd;

        if (text[0] == '\0')
                return (NULL);

        if (*text == '~')
                text++;

        if (state == 0)
                setpwent();

        while ((pwd = getpwent()) && text[0] == pwd->pw_name[0]
            && strcmp(text, pwd->pw_name) == 0);

        if (pwd == NULL) {
                endpwent();
                return (NULL);
        }
        return (strdup(pwd->pw_name));
#endif
}


/*
 * el-compatible wrapper around rl_complete; needed for key binding
 */
/* ARGSUSED */
static unsigned char
_el_rl_complete(EditLine *el, int ch)
{
        return (unsigned char) rl_complete(0, ch);
}


/*
 * returns list of completitions for text given
 */
char **
completion_matches(const char *text, CPFunction *genfunc)
{
        char **match_list = NULL, *retstr, *prevstr;
        size_t match_list_len, max_equal, which, i;
        int matches;

        if (h == NULL || e == NULL)
                rl_initialize();

        matches = 0;
        match_list_len = 1;
        while ((retstr = (*genfunc) (text, matches)) != NULL) {
                if (matches + 1 >= match_list_len) {
                        match_list_len <<= 1;
                        match_list = realloc(match_list,
                            match_list_len * sizeof(char *));
                }
                match_list[++matches] = retstr;
        }

        if (!match_list)
                return (char **) NULL;  /* nothing found */

        /* find least denominator and insert it to match_list[0] */
        which = 2;
        prevstr = match_list[1];
        max_equal = strlen(prevstr);
        for (; which <= matches; which++) {
                for (i = 0; i < max_equal &&
                    prevstr[i] == match_list[which][i]; i++)
                        continue;
                max_equal = i;
        }

        retstr = malloc(max_equal + 1);
        (void) strncpy(retstr, match_list[1], max_equal);
        retstr[max_equal] = '\0';
        match_list[0] = retstr;

        /* add NULL as last pointer to the array */
        if (matches + 1 >= match_list_len)
                match_list = realloc(match_list,
                    (match_list_len + 1) * sizeof(char *));
        match_list[matches + 1] = (char *) NULL;

        return (match_list);
}

/*
 * Sort function for qsort(). Just wrapper around strcasecmp().
 */
static int
_rl_qsort_string_compare(i1, i2)
        const void *i1, *i2;
{
        /*LINTED const castaway*/
        const char *s1 = ((const char **)i1)[0];
        /*LINTED const castaway*/
        const char *s2 = ((const char **)i2)[0];

        return strcasecmp(s1, s2);
}

/*
 * Display list of strings in columnar format on readline's output stream.
 * 'matches' is list of strings, 'len' is number of strings in 'matches',
 * 'max' is maximum length of string in 'matches'.
 */
void
rl_display_match_list (matches, len, max)
     char **matches;
     int len, max;
{
        int i, idx, limit, count;
        int screenwidth = e->el_term.t_size.h;

        /*
         * Find out how many entries can be put on one line, count
         * with two spaces between strings.
         */
        limit = screenwidth / (max + 2);
        if (limit == 0)
                limit = 1;

        /* how many lines of output */
        count = len / limit;
        if (count * limit < len)
                count++;

        /* Sort the items if they are not already sorted. */
        qsort(&matches[1], (size_t)(len - 1), sizeof(char *),
            _rl_qsort_string_compare);

        idx = 1;
        for(; count > 0; count--) {
                for(i=0; i < limit && matches[idx]; i++, idx++)
                        e->el_std_printf(e, "%-*s  ", max, matches[idx]);
                e->el_std_printf(e, "\n");
        }
}

/*
 * Complete the word at or before point, called by rl_complete()
 * 'what_to_do' says what to do with the completion.
 * `?' means list the possible completions.
 * TAB means do standard completion.
 * `*' means insert all of the possible completions.
 * `!' means to do standard completion, and list all possible completions if
 * there is more than one.
 *
 * Note: '*' support is not implemented
 */
static int
rl_complete_internal(int what_to_do)
{
        CPFunction *complet_func;
        const LineInfo *li;
        char *temp, **matches;
        const char *ctemp;
        size_t len;

        rl_completion_type = what_to_do;

        if (h == NULL || e == NULL)
                rl_initialize();

        complet_func = rl_completion_entry_function;
        if (!complet_func)
                complet_func = filename_completion_function;

        /* We now look backwards for the start of a filename/variable word */
        li = el_line(e);
        ctemp = (const char *) li->cursor;
        while (ctemp > li->buffer
            && !strchr(rl_basic_word_break_characters, ctemp[-1])
            && (!rl_special_prefixes
                        || !strchr(rl_special_prefixes, ctemp[-1]) ) )
                ctemp--;

        len = li->cursor - ctemp;
        temp = alloca(len + 1);
        (void) strncpy(temp, ctemp, len);
        temp[len] = '\0';

        /* these can be used by function called in completion_matches() */
        /* or (*rl_attempted_completion_function)() */
        rl_point = li->cursor - li->buffer;
        rl_end = li->lastchar - li->buffer;

        if (!rl_attempted_completion_function)
                matches = completion_matches(temp, complet_func);
        else {
                int end = li->cursor - li->buffer;
                matches = (*rl_attempted_completion_function) (temp, (int)
                    (end - len), end);
        }

        if (matches) {
                int i, retval = CC_REFRESH;
                int matches_num, maxlen, match_len, match_display=1;

                /*
                 * Only replace the completed string with common part of
                 * possible matches if there is possible completion.
                 */
                if (matches[0][0] != '\0') {
                        el_deletestr(e, (int) len);
                        el_insertstr(e, matches[0]);
                }

                if (what_to_do == '?')
                        goto display_matches;

                if (matches[2] == NULL && strcmp(matches[0], matches[1]) == 0) {
                        /*
                         * We found exact match. Add a space after
                         * it, unless we do filename completition and the
                         * object is a directory.
                         */
                        size_t alen = strlen(matches[0]);
                        if ((complet_func != filename_completion_function
                              || (alen > 0 && (matches[0])[alen - 1] != '/'))
                            && rl_completion_append_character) {
                                char buf[2];
                                buf[0] = rl_completion_append_character;
                                buf[1] = '\0';
                                el_insertstr(e, buf);
                        }
                } else if (what_to_do == '!') {
    display_matches:
                        /*
                         * More than one match and requested to list possible
                         * matches.
                         */

                        for(i=1, maxlen=0; matches[i]; i++) {
                                match_len = strlen(matches[i]);
                                if (match_len > maxlen)
                                        maxlen = match_len;
                        }
                        matches_num = i - 1;
                                
                        /* newline to get on next line from command line */
                        e->el_std_printf(e, "\n");

                        /*
                         * If there are too many items, ask user for display
                         * confirmation.
                         */
                        if (matches_num > rl_completion_query_items) {
                                e->el_std_printf(e,
                                "Display all %d possibilities? (y or n) ",
                                        matches_num);
                                e->el_std_flush(e);
                                if (getc(stdin) != 'y')
                                        match_display = 0;
                                e->el_std_printf(e, "\n");
                        }

                        if (match_display)
                                rl_display_match_list(matches, matches_num,
                                        maxlen);
                        retval = CC_REDISPLAY;
                } else if (matches[0][0]) {
                        /*
                         * There was some common match, but the name was
                         * not complete enough. Next tab will print possible
                         * completions.
                         */
                        el_beep(e);
                } else {
                        /* lcd is not a valid object - further specification */
                        /* is needed */
                        el_beep(e);
                        retval = CC_NORM;
                }

                /* free elements of array and the array itself */
                for (i = 0; matches[i]; i++)
                        free(matches[i]);
                free(matches), matches = NULL;

                return (retval);
        }
        return (CC_NORM);
}


/*
 * complete word at current point
 */
int
rl_complete(int ignore, int invoking_key)
{
        if (h == NULL || e == NULL)
                rl_initialize();

        if (rl_inhibit_completion) {
                rl_insert(ignore, invoking_key);
                return (CC_REFRESH);
        } else if (e->el_state.lastcmd == el_rl_complete_cmdnum)
                return rl_complete_internal('?');
        else if (_rl_complete_show_all)
                return rl_complete_internal('!');
        else
                return (rl_complete_internal(TAB));
}


/*
 * misc other functions
 */

/*
 * bind key c to readline-type function func
 */
int
rl_bind_key(int c, int func(int, int))
{
        int retval = -1;

        if (h == NULL || e == NULL)
                rl_initialize();

        if (func == rl_insert) {
                /* XXX notice there is no range checking of ``c'' */
                e->el_map.key[c] = ED_INSERT;
                retval = 0;
        }
        return (retval);
}


/*
 * read one key from input - handles chars pushed back
 * to input stream also
 */
int
rl_read_key(void)
{
        char fooarr[2 * sizeof(int)];

        if (e == NULL || h == NULL)
                rl_initialize();

        return (el_getc(e, fooarr));
}


/*
 * reset the terminal
 */
/* ARGSUSED */
void
rl_reset_terminal(const char *p)
{

        if (h == NULL || e == NULL)
                rl_initialize();
        el_reset(e);
}


/*
 * insert character ``c'' back into input stream, ``count'' times
 */
int
rl_insert(int count, int c)
{
        char arr[2];

        if (h == NULL || e == NULL)
                rl_initialize();

        /* XXX - int -> char conversion can lose on multichars */
        arr[0] = c;
        arr[1] = '\0';

        for (; count > 0; count--)
                el_push(e, arr);

        return (0);
}