xref: /src/usr.bin/mail/complete.c

/*	$NetBSD: complete.c,v 1.8 2006/10/02 16:43:31 christos Exp $	*/

/*-
 * Copyright (c) 1997-2000,2005 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn.
 *
 * 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.
 */

/* Most of this is derived or copied from src/usr.bin/ftp/complete.c (1.41). */


#ifdef USE_READLINE

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: complete.c,v 1.8 2006/10/02 16:43:31 christos Exp $");
#endif /* not lint */

/*
 * FTP user program - command and file completion routines
 */

#include <sys/stat.h>

#include <ctype.h>
#include <err.h>
#include <dirent.h>
#include <glob.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <histedit.h>
#include <sys/param.h>
#include <stringlist.h>

#include "rcv.h"			/* includes "glob.h" */
#include "extern.h"
#include "complete.h"

/*
 * Global variables
 */
static int doglob = 1;			/* glob local file names */

#define ttyout stdout
#define ttywidth screenwidth		/* in "glob.h" */
#define ttyheight screenheight		/* in "glob.h" */


/* This should find the first command that matches the name given or
 * NULL if none.  Use the routine from mail in lex.c.
 */
#define getcmd(w) lex(w)


/************************************************************************/
/* from src/usr.bin/ftp/utils.h (1.135) */

/*
 * List words in stringlist, vertically arranged
 */
static void
list_vertical(StringList *sl)
{
	int i, j;
	int columns, lines;
	char *p;
	size_t w, width;

	width = 0;

	for (i = 0 ; i < sl->sl_cur ; i++) {
		w = strlen(sl->sl_str[i]);
		if (w > width)
			width = w;
	}
	width = (width + 8) &~ 7;

	columns = ttywidth / width;
	if (columns == 0)
		columns = 1;
	lines = (sl->sl_cur + columns - 1) / columns;
	for (i = 0; i < lines; i++) {
		for (j = 0; j < columns; j++) {
			p = sl->sl_str[j * lines + i];
			if (p)
				fputs(p, ttyout);
			if (j * lines + i + lines >= sl->sl_cur) {
				putc('\n', ttyout);
				break;
			}
			if (p) {
				w = strlen(p);
				while (w < width) {
					w = (w + 8) &~ 7;
					(void)putc('\t', ttyout);
				}
			}
		}
	}
}

/*
 * Copy characters from src into dst, \ quoting characters that require it
 */
static void
ftpvis(char *dst, size_t dstlen, const char *src, size_t srclen)
{
	int	di, si;

	for (di = si = 0;
	    src[si] != '\0' && di < dstlen && si < srclen;
	    di++, si++) {
		switch (src[si]) {
		case '\\':
		case ' ':
		case '\t':
		case '\r':
		case '\n':
		case '"':
			dst[di++] = '\\';
			if (di >= dstlen)
				break;
			/* FALLTHROUGH */
		default:
			dst[di] = src[si];
		}
	}
	dst[di] = '\0';
}

/*
 * sl_init() with inbuilt error checking
 */
static StringList *
ftp_sl_init(void)
{
	StringList *p;

	p = sl_init();
	if (p == NULL)
		err(1, "Unable to allocate memory for stringlist");
	return (p);
}


/*
 * sl_add() with inbuilt error checking
 */
static void
ftp_sl_add(StringList *sl, char *i)
{

	if (sl_add(sl, i) == -1)
		err(1, "Unable to add `%s' to stringlist", i);
}

/*
 * strdup() with inbuilt error checking
 */
static char *
ftp_strdup(const char *str)
{
	char *s;

	if (str == NULL)
		errx(1, "ftp_strdup() called with NULL argument");
	s = strdup(str);
	if (s == NULL)
		err(1, "Unable to allocate memory for string copy");
	return (s);
}

/*
 * Glob a local file name specification with the expectation of a single
 * return value. Can't control multiple values being expanded from the
 * expression, we return only the first.
 * Returns NULL on error, or a pointer to a buffer containing the filename
 * that's the caller's responsiblity to free(3) when finished with.
 */
static char *
globulize(const char *pattern)
{
	glob_t gl;
	int flags;
	char *p;

	if (!doglob)
		return (ftp_strdup(pattern));

	flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
	memset(&gl, 0, sizeof(gl));
	if (glob(pattern, flags, NULL, &gl) || gl.gl_pathc == 0) {
		warnx("%s: not found", pattern);
		globfree(&gl);
		return (NULL);
	}
	p = ftp_strdup(gl.gl_pathv[0]);
	globfree(&gl);
	return (p);
}

/* from src/usr.bin/ftp/utils.h (1.135) */
/************************************************************************/

static int
comparstr(const void *a, const void *b)
{
	return (strcmp(*(const char * const *)a, *(const char * const *)b));
}

/*
 * Determine if complete is ambiguous. If unique, insert.
 * If no choices, error. If unambiguous prefix, insert that.
 * Otherwise, list choices. words is assumed to be filtered
 * to only contain possible choices.
 * Args:
 *	word	word which started the match
 *	list	list by default
 *	words	stringlist containing possible matches
 * Returns a result as per el_set(EL_ADDFN, ...)
 */
static unsigned char
complete_ambiguous(EditLine *el, char *word, int list, StringList *words)
{
	char insertstr[MAXPATHLEN];
	char *lastmatch, *p;
	int i, j;
	size_t matchlen, wordlen;

	wordlen = strlen(word);
	if (words->sl_cur == 0)
		return (CC_ERROR);	/* no choices available */

	if (words->sl_cur == 1) {	/* only once choice available */
		p = words->sl_str[0] + wordlen;
		if (*p == '\0')		/* at end of word? */
			return (CC_REFRESH);
		ftpvis(insertstr, sizeof(insertstr), p, strlen(p));
		if (el_insertstr(el, insertstr) == -1)
			return (CC_ERROR);
		else
			return (CC_REFRESH);
	}

	if (!list) {
		matchlen = 0;
		lastmatch = words->sl_str[0];
		matchlen = strlen(lastmatch);
		for (i = 1 ; i < words->sl_cur ; i++) {
			for (j = wordlen ; j < strlen(words->sl_str[i]); j++)
				if (lastmatch[j] != words->sl_str[i][j])
					break;
			if (j < matchlen)
				matchlen = j;
		}
		if (matchlen > wordlen) {
			ftpvis(insertstr, sizeof(insertstr),
			    lastmatch + wordlen, matchlen - wordlen);
			if (el_insertstr(el, insertstr) == -1)
				return (CC_ERROR);
			else
				return (CC_REFRESH_BEEP);
		}
	}

	putc('\n', ttyout);
	qsort(words->sl_str, words->sl_cur, sizeof(char *), comparstr);
	list_vertical(words);
	return (CC_REDISPLAY);
}

/*
 * Complete a mail command.
 */
static unsigned char
complete_command(EditLine *el, char *word, int list)
{
	const struct cmd *c;
	StringList *words;
	size_t wordlen;
	unsigned char rv;

	words = ftp_sl_init();
	wordlen = strlen(word);

	for (c = cmdtab; c->c_name != NULL; c++) {
		if (wordlen > strlen(c->c_name))
			continue;
		if (strncmp(word, c->c_name, wordlen) == 0)
			ftp_sl_add(words, __UNCONST(c->c_name));
	}

	rv = complete_ambiguous(el, word, list, words);
	if (rv == CC_REFRESH) {
		if (el_insertstr(el, " ") == -1)
			rv = CC_ERROR;
	}
	sl_free(words, 0);
	return (rv);
}

/*
 * Complete a local filename.
 */
static unsigned char
complete_filename(EditLine *el, char *word, int list)
{
	StringList *words;
	char dir[MAXPATHLEN];
	char *fname;
	DIR *dd;
	struct dirent *dp;
	unsigned char rv;
	size_t len;

	if ((fname = strrchr(word, '/')) == NULL) {
		dir[0] = '.';
		dir[1] = '\0';
		fname = word;
	} else {
		if (fname == word) {
			dir[0] = '/';
			dir[1] = '\0';
		} else
			(void)strlcpy(dir, word, fname - word + 1);
		fname++;
	}
	if (dir[0] == '~') {
		char *p;

		if ((p = globulize(dir)) == NULL)
			return (CC_ERROR);
		(void)strlcpy(dir, p, sizeof(dir));
		free(p);
	}

	if ((dd = opendir(dir)) == NULL)
		return (CC_ERROR);

	words = ftp_sl_init();
	len = strlen(fname);

	for (dp = readdir(dd); dp != NULL; dp = readdir(dd)) {
		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
			continue;

#if defined(DIRENT_MISSING_D_NAMLEN)
		if (len > strlen(dp->d_name))
			continue;
#else
		if (len > dp->d_namlen)
			continue;
#endif
		if (strncmp(fname, dp->d_name, len) == 0) {
			char *tcp;

			tcp = ftp_strdup(dp->d_name);
			ftp_sl_add(words, tcp);
		}
	}
	closedir(dd);

	rv = complete_ambiguous(el, fname, list, words);
	if (rv == CC_REFRESH) {
		struct stat sb;
		char path[MAXPATHLEN];

		(void)strlcpy(path, dir,		sizeof(path));
		(void)strlcat(path, "/",		sizeof(path));
		(void)strlcat(path, words->sl_str[0],	sizeof(path));

		if (stat(path, &sb) >= 0) {
			char suffix[2] = " ";

			if (S_ISDIR(sb.st_mode))
				suffix[0] = '/';
			if (el_insertstr(el, suffix) == -1)
				rv = CC_ERROR;
		}
	}
	sl_free(words, 1);
	return (rv);
}

static int
find_execs(char *word, char *path, StringList *list)
{
	char *sep;
	char *dir=path;
	DIR *dd;
	struct dirent *dp;
	int len = strlen(word);
	uid_t uid = getuid();
	gid_t gid = getgid();

	for (sep=dir ; sep ; dir=sep+1) {
		if ((sep=strchr(dir, ':')) != NULL) {
			*sep=0;
		}

		if ((dd = opendir(dir)) == NULL) {
			perror("dir");
			return -1;
		}

		for (dp = readdir(dd); dp != NULL; dp = readdir(dd)) {

			if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
				continue;

#if defined(DIRENT_MISSING_D_NAMLEN)
			if (len > strlen(dp->d_name))
				continue;
#else
			if (len > dp->d_namlen)
				continue;
#endif

			if (strncmp(word, dp->d_name, len) == 0) {
				struct stat sb;
				char pathname[ MAXPATHLEN ];
				unsigned mask;

				snprintf(pathname, sizeof(pathname), "%s/%s", dir, dp->d_name);
				if (stat(pathname, &sb) != 0) {
					perror(pathname);
					continue;
				}

				mask = 0001;
				if (sb.st_uid == uid)	mask |= 0100;
				if (sb.st_gid == gid)	mask |= 0010;

				if ((sb.st_mode & mask) != 0) {
					char *tcp;
					tcp = strdup(dp->d_name);
					sl_add(list, tcp);
				}
			}

		}

		closedir(dd);
	}

	return 0;
}


/*
 * Complete a local executable
 */
static unsigned char
complete_executable(EditLine *el, char *word, int list)
{
	StringList *words;
	char dir[ MAXPATHLEN ];
	char *fname;
	unsigned char rv;
	int error;

	if ((fname = strrchr(word, '/')) == NULL) {
		dir[0] = '\0';		/* walk the path */
		fname = word;
	} else {
		if (fname == word) {
			dir[0] = '/';
			dir[1] = '\0';
		} else {
			(void)strncpy(dir, word, fname - word);
			dir[fname - word] = '\0';
		}
		fname++;
	}

	words = sl_init();

	if (*dir == '\0') {		/* walk path */
		char *env;
		char *path;
		int len;
		env = getenv("PATH");
		len = strlen(env);
		path = salloc(len + 1);
		strcpy(path, env);
		error = find_execs(word, path, words);
	}
	else {		/* check specified dir only */
		error = find_execs(word, dir, words);
	}
	if (error != 0)
		return CC_ERROR;

	rv = complete_ambiguous(el, fname, list, words);

	if (rv == CC_REFRESH)
		if (el_insertstr(el, " ") == -1)
			rv = CC_ERROR;

	sl_free(words, 1);

	return (rv);
}


static unsigned
char complete_set(EditLine *el, char *word, int list)
{
	struct var *vp;
	char **ap;
	char **p;
	int h;
	int s;
	int len = strlen(word);
	StringList *words;
	unsigned char rv;

	words = sl_init();

	/* allocate space for variables table */
	for (h = 0, s = 1; h < HSHSIZE; h++)
		for (vp = variables[h]; vp != NULL; vp = vp->v_link)
			s++;
	ap = (char **) salloc(s * sizeof *ap);

	/* save pointers */
	for (h = 0, p = ap; h < HSHSIZE; h++)
		for (vp = variables[h]; vp != NULL; vp = vp->v_link)
			*p++ = vp->v_name;
	*p = NULL;

	/* sort pointers */
	sort(ap);

	/* complete on list */
	for (p = ap; *p != NULL; p++) {
		if (len == 0 || strncmp(*p, word, len) == 0) {
			char *tcp;
			tcp = strdup(*p);
			sl_add(words, tcp);
		}
	}

	rv = complete_ambiguous(el, word, list, words);

	sl_free(words, 1);

	return(rv);
}





static unsigned char
complete_alias(EditLine *el, char *word, int list)
{
	struct grouphead *gh;
	char **ap;
	char **p;
	int h;
	int s;
	int len = strlen(word);
	StringList *words;
	unsigned char rv;

	words = sl_init();

	/* allocate space for alias table */
	for (h = 0, s = 1; h < HSHSIZE; h++)
		for (gh = groups[h]; gh != NULL; gh = gh->g_link)
			s++;
	ap = (char **) salloc(s * sizeof *ap);

	/* save pointers */
	for (h = 0, p = ap; h < HSHSIZE; h++)
		for (gh = groups[h]; gh != NULL; gh = gh->g_link)
			*p++ = gh->g_name;
	*p = NULL;

	/* sort pointers */
	sort(ap);

	/* complete on list */
	for (p = ap; *p != NULL; p++) {
		if (len == 0 || strncmp(*p, word, len) == 0) {
			char *tcp;
			tcp = strdup(*p);
			sl_add(words, tcp);
		}
	}

	rv = complete_ambiguous(el, word, list, words);
	if (rv == CC_REFRESH)
		if (el_insertstr(el, " ") == -1)
			rv = CC_ERROR;

	sl_free(words, 1);

	return(rv);
}



static char	*stringbase;	/* current scan point in line buffer */
static char	*argbase;	/* current storage point in arg buffer */
static StringList *marg_sl;	/* stringlist containing margv */
static int	margc;		/* count of arguments on input line */
#define margv (marg_sl->sl_str)	/* args parsed from input line */

static char *cursor_pos;
static int   cursor_argc;
static int   cursor_argo;

static void
init_complete(void)
{
	marg_sl = sl_init();
	return;
}



/************************************************************************/
/* from /usr/src/usr.bin/ftp/main.c(1.101) */

static int   slrflag;
static char *altarg;		/* argv[1] with no shell-like preprocessing  */

#ifdef NO_EDITCOMPLETE
#define	INC_CHKCURSOR(x)	(x)++
#else  /* !NO_EDITCOMPLETE */
#define	INC_CHKCURSOR(x)				\
	do {						\
		(x)++ ;					\
		if (x == cursor_pos) {			\
			cursor_argc = margc;		\
			cursor_argo = ap - argbase;	\
			cursor_pos  = NULL;		\
		}					\
	} while(0)
#endif /* !NO_EDITCOMPLETE */

/*
 * Parse string into argbuf;
 * implemented with FSM to
 * handle quoting and strings
 */
static char *
slurpstring(void)
{
	int got_one = 0;
	char *sb = stringbase;
	char *ap = argbase;
	char *tmp = argbase;		/* will return this if token found */

	if (*sb == '!' || *sb == '$') {	/* recognize ! as a token for shell */
		switch (slrflag) {	/* and $ as token for macro invoke */
			case 0:
				slrflag++;
				INC_CHKCURSOR(stringbase);
				return __UNCONST((*sb == '!') ? "!" : "$");
				/* NOTREACHED */
			case 1:
				slrflag++;
				altarg = stringbase;
				break;
			default:
				break;
		}
	}

S0:
	switch (*sb) {

	case '\0':
		goto OUT;

	case ' ':
	case '\t':
		INC_CHKCURSOR(sb);
		goto S0;

	default:
		switch (slrflag) {
			case 0:
				slrflag++;
				break;
			case 1:
				slrflag++;
				altarg = sb;
				break;
			default:
				break;
		}
		goto S1;
	}

S1:
	switch (*sb) {

	case ' ':
	case '\t':
	case '\0':
		goto OUT;	/* end of token */

	case '\\':
		INC_CHKCURSOR(sb);
		goto S2;	/* slurp next character */

	case '"':
		INC_CHKCURSOR(sb);
		goto S3;	/* slurp quoted string */

	default:
		/* the first arg (command) is special - see execute() in lex.c */
		if (margc == 0 && got_one &&
		    strchr(" \t0123456789$^.:/-+*'\"", *sb))
			goto OUT;

		*ap = *sb;	/* add character to token */
		ap++;
		INC_CHKCURSOR(sb);
		got_one = 1;
		goto S1;
	}

S2:
	switch (*sb) {

	case '\0':
		goto OUT;

	default:
		*ap = *sb;
		ap++;
		INC_CHKCURSOR(sb);
		got_one = 1;
		goto S1;
	}

S3:
	switch (*sb) {

	case '\0':
		goto OUT;

	case '"':
		INC_CHKCURSOR(sb);
		goto S1;

	default:
		*ap = *sb;
		ap++;
		INC_CHKCURSOR(sb);
		got_one = 1;
		goto S3;
	}

OUT:
	if (got_one)
		*ap++ = '\0';
	argbase = ap;			/* update storage pointer */
	stringbase = sb;		/* update scan pointer */
	if (got_one) {
		return (tmp);
	}
	switch (slrflag) {
		case 0:
			slrflag++;
			break;
		case 1:
			slrflag++;
			altarg = NULL;
			break;
		default:
			break;
	}
	return (NULL);
}


/*
 * Slice a string up into argc/argv.
 */
static void
makeargv(char *line)
{
	static char argbuf[ LINESIZE ];	/* argument storage buffer */
	char *argp;

	stringbase = line;		/* scan from first of buffer */
	argbase = argbuf;		/* store from first of buffer */
	slrflag = 0;
	marg_sl->sl_cur = 0;		/* reset to start of marg_sl */
	for (margc = 0; ; margc++) {
		argp = slurpstring();
		ftp_sl_add(marg_sl, argp);
		if (argp == NULL)
			break;
	}
#ifndef NO_EDITCOMPLETE
	if (cursor_pos == line) {
		cursor_argc = 0;
		cursor_argo = 0;
	} else if (cursor_pos != NULL) {
		cursor_argc = margc;
		cursor_argo = strlen(margv[margc-1]);
	}
#endif /* !NO_EDITCOMPLETE */
}

/* from /usr/src/usr.bin/ftp/main.c(1.101) */
/************************************************************************/


/*
 * Generic complete routine
 */
static unsigned char
complete(EditLine *el, int ch)
{
	static char line[LINESIZE];	/* input line buffer */
	static char word[LINESIZE];
	static int lastc_argc, lastc_argo;

	const struct cmd *c;
	const LineInfo *lf;
	int celems, dolist, cmpltype;
	size_t len;

	lf = el_line(el);
	len = lf->lastchar - lf->buffer;
#if 1
	if (ch == 04) {	/* CTRL-D is special */
		if (len == 0)
			return (CC_EOF);
		if (lf->lastchar != lf->cursor) {
			el_push(el, __UNCONST("")); /* delete current char without using ^D */
			return (CC_NORM);
		}
	}
#endif
	if (len >= sizeof(line))
		return (CC_ERROR);
	(void)strlcpy(line, lf->buffer, len + 1);
	cursor_pos = line + (lf->cursor - lf->buffer);
	lastc_argc = cursor_argc;	/* remember last cursor pos */
	lastc_argo = cursor_argo;
	makeargv(line);			/* build argc/argv of current line */

	if (cursor_argo >= sizeof(word))
		return (CC_ERROR);

	dolist = 0;
	/* if cursor and word are the same, list alternatives */
	if (lastc_argc == cursor_argc && lastc_argo == cursor_argo
	    && strncmp(word, margv[cursor_argc] ? margv[cursor_argc] : "",
		       cursor_argo) == 0)
		dolist = 1;
	else if (cursor_argc < margc)
		(void)strlcpy(word, margv[cursor_argc], cursor_argo + 1);
	word[cursor_argo] = '\0';

	if (cursor_argc == 0)
		return (complete_command(el, word, dolist));

	c = getcmd(margv[0]);
	if (c == NULL)
		return (CC_ERROR);
	celems = strlen(c->c_complete);

		/* check for 'continuation' completes (which are uppercase) */
	if ((cursor_argc > celems) && (celems > 0)
	    && isupper((unsigned char) c->c_complete[celems-1]))
		cursor_argc = celems;

	if (cursor_argc > celems)
		return (CC_ERROR);

	cmpltype = c->c_complete[cursor_argc - 1];
	switch (cmpltype) {
		case 'a':			/* alias complete */
		case 'A':
			return (complete_alias(el, word, dolist));

		case 'c':			/* command complete */
		case 'C':
			return (complete_command(el, word, dolist));

		case 'f':			/* filename complete */
		case 'F':
			return (complete_filename(el, word, dolist));

		case 'n':			/* no complete */
		case 'N':			/* no complete */
			return (CC_ERROR);

		case 's':
		case 'S':
			return (complete_set(el, word, dolist));

		case 'x':			/* executable complete */
		case 'X':
			return (complete_executable(el, word, dolist));

		default:
			errx(1, "unknown complete type `%c'", cmpltype);
			return (CC_ERROR);
	}
	/* NOTREACHED */
}


/*************************************************************************/
/* Most of this was originally taken directly from the readline manpage. */

static struct {
	EditLine *el;		/* editline(3) with completion and history */
	EditLine *elo;		/* editline(3) editline only, no completion */
	History  *hist;		/* editline(3) history structure */
	const char *prompt;	/* prompt */
} rl_global = {
	.el = NULL,
	.hist = NULL,
	.prompt = NULL
};

char *
rl_gets(const char *prompt)
{
	int cnt;
	const char *buf;
	HistEvent ev;
	static char line[LINE_MAX];

	rl_global.prompt = prompt;
	buf = el_gets(rl_global.el, &cnt);

	if (buf == NULL || cnt <= 0)
		return NULL;

	/* enter the line into history */
	if (history(rl_global.hist, &ev, H_ENTER, buf) == 0)
		printf("Failed history entry: %s", buf);
#ifdef DEBUG
	else
		printf("history entry: %s\n", ev.str);
#endif

	cnt--;	/* trash the trailing LF */
	cnt = MIN(sizeof(line) - 1, cnt);
	(void)memcpy(line, buf, cnt);
	line[cnt] = '\0';

	return line;
}


/*
 * Edit a line containing string, with no history or completion.
 */
char *
rl_getline(const char *prompt, char *string)
{
	static char line[LINE_MAX];
	const char *buf;
	int cnt;

	rl_global.prompt = prompt;

	if (string)
		el_push(rl_global.elo, string);

	buf = el_gets(rl_global.elo, &cnt);
	if (buf == NULL || cnt <= 0) {
		if (cnt == 0)
			fputc('\n', stdout);
	  	line[0] = '\0';
		return line;
	}

	cnt--;
	cnt = MIN(sizeof(line) - 1, cnt);
	(void)memcpy(line, buf, cnt);
	line[cnt] = '\0';

	return line;
}


static const char *
show_prompt(EditLine *e __attribute__((unused)))
{
	return rl_global.prompt;
}

void
init_readline(void)
{
	HistEvent ev;
	const char *el_editor;
	const char *el_history_size;
	char *el_completion_keys;

	rl_global.hist = history_init();	/* init the builtin history */
	el_history_size = value("el_history_size");
	if (el_history_size == NULL)
		el_history_size = "0";
	if (history(rl_global.hist, &ev, H_SETSIZE, atoi(el_history_size)))
		printf("history: %s\n", ev.str);

	rl_global.el  = el_init(getprogname(), stdin, stdout, stderr);
	rl_global.elo = el_init(getprogname(), stdin, stdout, stderr);

	el_editor = value("el_editor");
	if (el_editor) {
		el_set(rl_global.el, EL_EDITOR, el_editor);
		el_set(rl_global.elo, EL_EDITOR, el_editor);
	}

	el_set(rl_global.el, EL_PROMPT, show_prompt);
	el_set(rl_global.elo, EL_PROMPT, show_prompt);
	el_set(rl_global.el, EL_HIST, history, rl_global.hist);	/* use history */
	el_source(rl_global.el, NULL);				/* read ~/.editrc */

	/* add local file completion, bind to TAB */
	el_set(rl_global.el, EL_ADDFN, "mail-complete",
	    "Context sensitive argument completion",
	    complete);

	el_completion_keys = value("el_completion_keys");
	if (el_completion_keys && *el_completion_keys) {
		struct name *np, *nq;
		np = lexpand(el_completion_keys, 0);
		for (nq = np ; nq ; nq = nq->n_flink)
			el_set(rl_global.el, EL_BIND, nq->n_name, "mail-complete", NULL);
	}

	init_complete();

	el_set(rl_global.el, EL_SIGNAL, 1);
	el_set(rl_global.elo, EL_SIGNAL, 1);

	return;
}

/************************************************************************/
#endif /* USE_READLINE */