readline.c

asterisk 是一个很有知名度开源软件

/*	$NetBSD: readline.c,v 1.21 2002/03/18 16:20:36 christos 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 "config.h"
#if !defined(lint) && !defined(SCCSID)
__RCSID("$NetBSD: readline.c,v 1.21 2002/03/18 16:20:36 christos Exp $");
#endif /* not lint && not SCCSID */

#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <pwd.h>
#include <ctype.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>

#ifdef SOLARIS
#include <alloca.h>
#endif

#include "histedit.h"
#include "readline/readline.h"
#include "el.h"
#include "fcns.h"		/* for EL_NUM_FCNS */

/* 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";
static char empty[] = { '\0' };
static char expand_chars[] = { ' ', '\t', '\n', '=', '(', '\0' };
static char break_chars[] = { ' ', '\t', '\n', '"', '\\', '\'', '`', '@', '$',
    '>', '<', '=', ';', '|', '&', '{', '(', '\0' };
char *rl_readline_name = empty;
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 = expand_chars;
Function *history_inhibit_expansion_function = NULL;

int rl_inhibit_completion = 0;
int rl_attempted_completion_over = 0;
char *rl_basic_word_break_characters = break_chars;
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, rl_instream, rl_outstream, stderr);

	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 completition 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);
	/* a cheesy way to get rid of const cast. */
	rl_line_buffer = memchr(li->buffer, *li->buffer, 1);
	rl_point = rl_end = 0;

	return (0);
}


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

	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) {
		int lastidx;

		buf = strdup(ret);
		lastidx = count - 1;
		if (buf[lastidx] == '\n')
			buf[lastidx] = '\0';
	} else
		buf = NULL;

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

	return buf;
}

/*
 * 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)