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Remove wpath from secure mode pledge.

Upstream removed history file support for secure mode. The history file
feature is off by default already, disallowing it altogether in secure
mode allows us to drop wpath.

Added a note about it to manual page.

ok benno, deraadt

/*
 * Copyright (C) 1984-2012  Mark Nudelman
 * Modified for use with illumos by Garrett D'Amore.
 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
 *
 * 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.
 */

/*
 * Functions which manipulate the command buffer.
 * Used only by command() and related functions.
 */

#include <sys/stat.h>

#include "charset.h"
#include "cmd.h"
#include "less.h"

extern int secure;
extern int sc_width;
extern int utf_mode;

static char cmdbuf[CMDBUF_SIZE]; /* Buffer for holding a multi-char command */
static int cmd_col;		/* Current column of the cursor */
static int prompt_col;		/* Column of cursor just after prompt */
static char *cp;		/* Pointer into cmdbuf */
static int cmd_offset;		/* Index into cmdbuf of first displayed char */
static int literal;		/* Next input char should not be interpreted */
static int updown_match = -1;	/* Prefix length in up/down movement */

static int cmd_complete(int);
/*
 * These variables are statics used by cmd_complete.
 */
static int in_completion = 0;
static char *tk_text;
static char *tk_original;
static char *tk_ipoint;
static char *tk_trial;
static struct textlist tk_tlist;

static int cmd_left(void);
static int cmd_right(void);

char openquote = '"';
char closequote = '"';

/* History file */
#define	HISTFILE_FIRST_LINE	".less-history-file:"
#define	HISTFILE_SEARCH_SECTION	".search"
#define	HISTFILE_SHELL_SECTION	".shell"

/*
 * A mlist structure represents a command history.
 */
struct mlist {
	struct mlist *next;
	struct mlist *prev;
	struct mlist *curr_mp;
	char *string;
	int modified;
};

/*
 * These are the various command histories that exist.
 */
struct mlist mlist_search =
	{ &mlist_search,  &mlist_search,  &mlist_search,  NULL, 0 };
void * const ml_search = (void *) &mlist_search;

struct mlist mlist_examine =
	{ &mlist_examine, &mlist_examine, &mlist_examine, NULL, 0 };
void * const ml_examine = (void *) &mlist_examine;

struct mlist mlist_shell =
	{ &mlist_shell,   &mlist_shell,   &mlist_shell,   NULL, 0 };
void * const ml_shell = (void *) &mlist_shell;

/*
 * History for the current command.
 */
static struct mlist *curr_mlist = NULL;
static int curr_cmdflags;

static char cmd_mbc_buf[MAX_UTF_CHAR_LEN];
static int cmd_mbc_buf_len;
static int cmd_mbc_buf_index;


/*
 * Reset command buffer (to empty).
 */
void
cmd_reset(void)
{
	cp = cmdbuf;
	*cp = '\0';
	cmd_col = 0;
	cmd_offset = 0;
	literal = 0;
	cmd_mbc_buf_len = 0;
	updown_match = -1;
}

/*
 * Clear command line.
 */
void
clear_cmd(void)
{
	cmd_col = prompt_col = 0;
	cmd_mbc_buf_len = 0;
	updown_match = -1;
}

/*
 * Display an ASCII string, usually as a prompt for input,
 * into the command buffer.
 */
void
cmd_putstr(char *s)
{
	while (*s != '\0') {
		putchr(*s++);
		cmd_col++;
		prompt_col++;
	}
}

/*
 * How many characters are in the command buffer?
 */
int
len_cmdbuf(void)
{
	char *s = cmdbuf;
	char *endline = s + strlen(s);
	int len = 0;

	while (*s != '\0') {
		step_char(&s, +1, endline);
		len++;
	}
	return (len);
}

/*
 * Common part of cmd_step_right() and cmd_step_left().
 */
static char *
cmd_step_common(char *p, LWCHAR ch, int len, int *pwidth, int *bswidth)
{
	char *pr;

	if (len == 1) {
		pr = prchar((int)ch);
		if (pwidth != NULL || bswidth != NULL) {
			int prlen = strlen(pr);
			if (pwidth != NULL)
				*pwidth = prlen;
			if (bswidth != NULL)
				*bswidth = prlen;
		}
	} else {
		pr = prutfchar(ch);
		if (pwidth != NULL || bswidth != NULL) {
			if (is_composing_char(ch)) {
				if (pwidth != NULL)
					*pwidth = 0;
				if (bswidth != NULL)
					*bswidth = 0;
			} else if (is_ubin_char(ch)) {
				int prlen = strlen(pr);
				if (pwidth != NULL)
					*pwidth = prlen;
				if (bswidth != NULL)
					*bswidth = prlen;
			} else {
				if (pwidth != NULL)
					*pwidth	= is_wide_char(ch) ? 2 : 1;
				if (bswidth != NULL)
					*bswidth = 1;
			}
		}
	}

	return (pr);
}

/*
 * Step a pointer one character right in the command buffer.
 */
static char *
cmd_step_right(char **pp, int *pwidth, int *bswidth)
{
	char *p = *pp;
	LWCHAR ch = step_char(pp, +1, p + strlen(p));

	return (cmd_step_common(p, ch, *pp - p, pwidth, bswidth));
}

/*
 * Step a pointer one character left in the command buffer.
 */
static char *
cmd_step_left(char **pp, int *pwidth, int *bswidth)
{
	char *p = *pp;
	LWCHAR ch = step_char(pp, -1, cmdbuf);

	return (cmd_step_common(*pp, ch, p - *pp, pwidth, bswidth));
}

/*
 * Repaint the line from cp onwards.
 * Then position the cursor just after the char old_cp (a pointer into cmdbuf).
 */
static void
cmd_repaint(char *old_cp)
{
	/*
	 * Repaint the line from the current position.
	 */
	clear_eol();
	while (*cp != '\0') {
		char *np = cp;
		int width;
		char *pr = cmd_step_right(&np, &width, NULL);
		if (cmd_col + width >= sc_width)
			break;
		cp = np;
		putstr(pr);
		cmd_col += width;
	}
	while (*cp != '\0') {
		char *np = cp;
		int width;
		char *pr = cmd_step_right(&np, &width, NULL);
		if (width > 0)
			break;
		cp = np;
		putstr(pr);
	}

	/*
	 * Back up the cursor to the correct position.
	 */
	while (cp > old_cp)
		cmd_left();
}

/*
 * Put the cursor at "home" (just after the prompt),
 * and set cp to the corresponding char in cmdbuf.
 */
static void
cmd_home(void)
{
	while (cmd_col > prompt_col) {
		int width, bswidth;

		cmd_step_left(&cp, &width, &bswidth);
		while (bswidth-- > 0)
			putbs();
		cmd_col -= width;
	}

	cp = &cmdbuf[cmd_offset];
}

/*
 * Shift the cmdbuf display left a half-screen.
 */
static void
cmd_lshift(void)
{
	char *s;
	char *save_cp;
	int cols;

	/*
	 * Start at the first displayed char, count how far to the
	 * right we'd have to move to reach the center of the screen.
	 */
	s = cmdbuf + cmd_offset;
	cols = 0;
	while (cols < (sc_width - prompt_col) / 2 && *s != '\0') {
		int width;
		cmd_step_right(&s, &width, NULL);
		cols += width;
	}
	while (*s != '\0') {
		int width;
		char *ns = s;
		cmd_step_right(&ns, &width, NULL);
		if (width > 0)
			break;
		s = ns;
	}

	cmd_offset = s - cmdbuf;
	save_cp = cp;
	cmd_home();
	cmd_repaint(save_cp);
}

/*
 * Shift the cmdbuf display right a half-screen.
 */
static void
cmd_rshift(void)
{
	char *s;
	char *save_cp;
	int cols;

	/*
	 * Start at the first displayed char, count how far to the
	 * left we'd have to move to traverse a half-screen width
	 * of displayed characters.
	 */
	s = cmdbuf + cmd_offset;
	cols = 0;
	while (cols < (sc_width - prompt_col) / 2 && s > cmdbuf) {
		int width;
		cmd_step_left(&s, &width, NULL);
		cols += width;
	}

	cmd_offset = s - cmdbuf;
	save_cp = cp;
	cmd_home();
	cmd_repaint(save_cp);
}

/*
 * Move cursor right one character.
 */
static int
cmd_right(void)
{
	char *pr;
	char *ncp;
	int width;

	if (*cp == '\0') {
		/* Already at the end of the line. */
		return (CC_OK);
	}
	ncp = cp;
	pr = cmd_step_right(&ncp, &width, NULL);
	if (cmd_col + width >= sc_width)
		cmd_lshift();
	else if (cmd_col + width == sc_width - 1 && cp[1] != '\0')
		cmd_lshift();
	cp = ncp;
	cmd_col += width;
	putstr(pr);
	while (*cp != '\0') {
		pr = cmd_step_right(&ncp, &width, NULL);
		if (width > 0)
			break;
		putstr(pr);
		cp = ncp;
	}
	return (CC_OK);
}

/*
 * Move cursor left one character.
 */
static int
cmd_left(void)
{
	char *ncp;
	int width, bswidth;

	if (cp <= cmdbuf) {
		/* Already at the beginning of the line */
		return (CC_OK);
	}
	ncp = cp;
	while (ncp > cmdbuf) {
		cmd_step_left(&ncp, &width, &bswidth);
		if (width > 0)
			break;
	}
	if (cmd_col < prompt_col + width)
		cmd_rshift();
	cp = ncp;
	cmd_col -= width;
	while (bswidth-- > 0)
		putbs();
	return (CC_OK);
}

/*
 * Insert a char into the command buffer, at the current position.
 */
static int
cmd_ichar(char *cs, int clen)
{
	char *s;

	if (strlen(cmdbuf) + clen >= sizeof (cmdbuf)-1) {
		/* No room in the command buffer for another char. */
		ring_bell();
		return (CC_ERROR);
	}

	/*
	 * Make room for the new character (shift the tail of the buffer right).
	 */
	for (s = &cmdbuf[strlen(cmdbuf)]; s >= cp; s--)
		s[clen] = s[0];
	/*
	 * Insert the character into the buffer.
	 */
	for (s = cp; s < cp + clen; s++)
		*s = *cs++;
	/*
	 * Reprint the tail of the line from the inserted char.
	 */
	updown_match = -1;
	cmd_repaint(cp);
	cmd_right();
	return (CC_OK);
}

/*
 * Backspace in the command buffer.
 * Delete the char to the left of the cursor.
 */
static int
cmd_erase(void)
{
	char *s;
	int clen;

	if (cp == cmdbuf) {
		/*
		 * Backspace past beginning of the buffer:
		 * this usually means abort the command.
		 */
		return (CC_QUIT);
	}
	/*
	 * Move cursor left (to the char being erased).
	 */
	s = cp;
	cmd_left();
	clen = s - cp;

	/*
	 * Remove the char from the buffer (shift the buffer left).
	 */
	for (s = cp; ; s++) {
		s[0] = s[clen];
		if (s[0] == '\0')
			break;
	}

	/*
	 * Repaint the buffer after the erased char.
	 */
	updown_match = -1;
	cmd_repaint(cp);

	/*
	 * We say that erasing the entire command string causes us
	 * to abort the current command, if CF_QUIT_ON_ERASE is set.
	 */
	if ((curr_cmdflags & CF_QUIT_ON_ERASE) && cp == cmdbuf && *cp == '\0')
		return (CC_QUIT);
	return (CC_OK);
}

/*
 * Delete the char under the cursor.
 */
static int
cmd_delete(void)
{
	if (*cp == '\0') {
		/* At end of string; there is no char under the cursor. */
		return (CC_OK);
	}
	/*
	 * Move right, then use cmd_erase.
	 */
	cmd_right();
	cmd_erase();
	return (CC_OK);
}

/*
 * Delete the "word" to the left of the cursor.
 */
static int
cmd_werase(void)
{
	if (cp > cmdbuf && cp[-1] == ' ') {
		/*
		 * If the char left of cursor is a space,
		 * erase all the spaces left of cursor (to the first non-space).
		 */
		while (cp > cmdbuf && cp[-1] == ' ')
			(void) cmd_erase();
	} else {
		/*
		 * If the char left of cursor is not a space,
		 * erase all the nonspaces left of cursor (the whole "word").
		 */
		while (cp > cmdbuf && cp[-1] != ' ')
			(void) cmd_erase();
	}
	return (CC_OK);
}

/*
 * Delete the "word" under the cursor.
 */
static int
cmd_wdelete(void)
{
	if (*cp == ' ') {
		/*
		 * If the char under the cursor is a space,
		 * delete it and all the spaces right of cursor.
		 */
		while (*cp == ' ')
			(void) cmd_delete();
	} else {
		/*
		 * If the char under the cursor is not a space,
		 * delete it and all nonspaces right of cursor (the whole word).
		 */
		while (*cp != ' ' && *cp != '\0')
			(void) cmd_delete();
	}
	return (CC_OK);
}

/*
 * Delete all chars in the command buffer.
 */
static int
cmd_kill(void)
{
	if (cmdbuf[0] == '\0') {
		/* Buffer is already empty; abort the current command. */
		return (CC_QUIT);
	}
	cmd_offset = 0;
	cmd_home();
	*cp = '\0';
	updown_match = -1;
	cmd_repaint(cp);

	/*
	 * We say that erasing the entire command string causes us
	 * to abort the current command, if CF_QUIT_ON_ERASE is set.
	 */
	if (curr_cmdflags & CF_QUIT_ON_ERASE)
		return (CC_QUIT);
	return (CC_OK);
}

/*
 * Select an mlist structure to be the current command history.
 */
void
set_mlist(void *mlist, int cmdflags)
{
	curr_mlist = (struct mlist *)mlist;
	curr_cmdflags = cmdflags;

	/* Make sure the next up-arrow moves to the last string in the mlist. */
	if (curr_mlist != NULL)
		curr_mlist->curr_mp = curr_mlist;
}

/*
 * Move up or down in the currently selected command history list.
 * Only consider entries whose first updown_match chars are equal to
 * cmdbuf's corresponding chars.
 */
static int
cmd_updown(int action)
{
	char *s;
	struct mlist *ml;

	if (curr_mlist == NULL) {
		/*
		 * The current command has no history list.
		 */
		ring_bell();
		return (CC_OK);
	}

	if (updown_match < 0) {
		updown_match = cp - cmdbuf;
	}

	/*
	 * Find the next history entry which matches.
	 */
	for (ml = curr_mlist->curr_mp; ; ) {
		ml = (action == EC_UP) ? ml->prev : ml->next;
		if (ml == curr_mlist) {
			/*
			 * We reached the end (or beginning) of the list.
			 */
			break;
		}
		if (strncmp(cmdbuf, ml->string, updown_match) == 0) {
			/*
			 * This entry matches; stop here.
			 * Copy the entry into cmdbuf and echo it on the screen.
			 */
			curr_mlist->curr_mp = ml;
			s = ml->string;
			if (s == NULL)
				s = "";
			cmd_home();
			clear_eol();
			strlcpy(cmdbuf, s, sizeof (cmdbuf));
			for (cp = cmdbuf; *cp != '\0'; )
				cmd_right();
			return (CC_OK);
		}
	}
	/*
	 * We didn't find a history entry that matches.
	 */
	ring_bell();
	return (CC_OK);
}

/*
 * Add a string to a history list.
 */
void
cmd_addhist(struct mlist *mlist, const char *cmd)
{
	struct mlist *ml;

	/*
	 * Don't save a trivial command.
	 */
	if (strlen(cmd) == 0)
		return;

	/*
	 * Save the command unless it's a duplicate of the
	 * last command in the history.
	 */
	ml = mlist->prev;
	if (ml == mlist || strcmp(ml->string, cmd) != 0) {
		/*
		 * Did not find command in history.
		 * Save the command and put it at the end of the history list.
		 */
		ml = ecalloc(1, sizeof (struct mlist));
		ml->string = estrdup(cmd);
		ml->next = mlist;
		ml->prev = mlist->prev;
		mlist->prev->next = ml;
		mlist->prev = ml;
	}
	/*
	 * Point to the cmd just after the just-accepted command.
	 * Thus, an UPARROW will always retrieve the previous command.
	 */
	mlist->curr_mp = ml->next;
}

/*
 * Accept the command in the command buffer.
 * Add it to the currently selected history list.
 */
void
cmd_accept(void)
{
	/*
	 * Nothing to do if there is no currently selected history list.
	 */
	if (curr_mlist == NULL)
		return;
	cmd_addhist(curr_mlist, cmdbuf);
	curr_mlist->modified = 1;
}

/*
 * Try to perform a line-edit function on the command buffer,
 * using a specified char as a line-editing command.
 * Returns:
 *	CC_PASS	The char does not invoke a line edit function.
 *	CC_OK	Line edit function done.
 *	CC_QUIT	The char requests the current command to be aborted.
 */
static int
cmd_edit(int c)
{
	int action;
	int flags;

#define	not_in_completion()	in_completion = 0

	/*
	 * See if the char is indeed a line-editing command.
	 */
	flags = 0;
	if (curr_mlist == NULL)
		/*
		 * No current history; don't accept history manipulation cmds.
		 */
		flags |= EC_NOHISTORY;
	if (curr_mlist == ml_search)
		/*
		 * In a search command; don't accept file-completion cmds.
		 */
		flags |= EC_NOCOMPLETE;

	action = editchar(c, flags);

	switch (action) {
	case EC_RIGHT:
		not_in_completion();
		return (cmd_right());
	case EC_LEFT:
		not_in_completion();
		return (cmd_left());
	case EC_W_RIGHT:
		not_in_completion();
		while (*cp != '\0' && *cp != ' ')
			cmd_right();
		while (*cp == ' ')
			cmd_right();
		return (CC_OK);
	case EC_W_LEFT:
		not_in_completion();
		while (cp > cmdbuf && cp[-1] == ' ')
			cmd_left();
		while (cp > cmdbuf && cp[-1] != ' ')
			cmd_left();
		return (CC_OK);
	case EC_HOME:
		not_in_completion();
		cmd_offset = 0;
		cmd_home();
		cmd_repaint(cp);
		return (CC_OK);
	case EC_END:
		not_in_completion();
		while (*cp != '\0')
			cmd_right();
		return (CC_OK);
	case EC_INSERT:
		not_in_completion();
		return (CC_OK);
	case EC_BACKSPACE:
		not_in_completion();
		return (cmd_erase());
	case EC_LINEKILL:
		not_in_completion();
		return (cmd_kill());
	case EC_ABORT:
		not_in_completion();
		(void) cmd_kill();
		return (CC_QUIT);
	case EC_W_BACKSPACE:
		not_in_completion();
		return (cmd_werase());
	case EC_DELETE:
		not_in_completion();
		return (cmd_delete());
	case EC_W_DELETE:
		not_in_completion();
		return (cmd_wdelete());
	case EC_LITERAL:
		literal = 1;
		return (CC_OK);
	case EC_UP:
	case EC_DOWN:
		not_in_completion();
		return (cmd_updown(action));
	case EC_F_COMPLETE:
	case EC_B_COMPLETE:
	case EC_EXPAND:
		return (cmd_complete(action));
	case EC_NOACTION:
		return (CC_OK);
	default:
		not_in_completion();
		return (CC_PASS);
	}
}

/*
 * Insert a string into the command buffer, at the current position.
 */
static int
cmd_istr(char *str)
{
	char *s;
	int action;
	char *endline = str + strlen(str);

	for (s = str; *s != '\0'; ) {
		char *os = s;
		step_char(&s, +1, endline);
		action = cmd_ichar(os, s - os);
		if (action != CC_OK) {
			ring_bell();
			return (action);
		}
	}
	return (CC_OK);
}

/*
 * Find the beginning and end of the "current" word.
 * This is the word which the cursor (cp) is inside or at the end of.
 * Return pointer to the beginning of the word and put the
 * cursor at the end of the word.
 */
static char *
delimit_word(void)
{
	char *word;
	char *p;
	int delim_quoted = 0;
	int meta_quoted = 0;
	char *esc = get_meta_escape();
	int esclen = strlen(esc);

	/*
	 * Move cursor to end of word.
	 */
	if (*cp != ' ' && *cp != '\0') {
		/*
		 * Cursor is on a nonspace.
		 * Move cursor right to the next space.
		 */
		while (*cp != ' ' && *cp != '\0')
			cmd_right();
	}

	/*
	 * Find the beginning of the word which the cursor is in.
	 */
	if (cp == cmdbuf)
		return (NULL);
	/*
	 * If we have an unbalanced quote (that is, an open quote
	 * without a corresponding close quote), we return everything
	 * from the open quote, including spaces.
	 */
	for (word = cmdbuf; word < cp; word++)
		if (*word != ' ')
			break;
	if (word >= cp)
		return (cp);
	for (p = cmdbuf; p < cp; p++) {
		if (meta_quoted) {
			meta_quoted = 0;
		} else if (esclen > 0 && p + esclen < cp &&
		    strncmp(p, esc, esclen) == 0) {
			meta_quoted = 1;
			p += esclen - 1;
		} else if (delim_quoted) {
			if (*p == closequote)
				delim_quoted = 0;
		} else { /* (!delim_quoted) */
			if (*p == openquote)
				delim_quoted = 1;
			else if (*p == ' ')
				word = p+1;
		}
	}
	return (word);
}

/*
 * Set things up to enter completion mode.
 * Expand the word under the cursor into a list of filenames
 * which start with that word, and set tk_text to that list.
 */
static void
init_compl(void)
{
	char *word;
	char c;

	free(tk_text);
	tk_text = NULL;
	/*
	 * Find the original (uncompleted) word in the command buffer.
	 */
	word = delimit_word();
	if (word == NULL)
		return;
	/*
	 * Set the insertion point to the point in the command buffer
	 * where the original (uncompleted) word now sits.
	 */
	tk_ipoint = word;
	/*
	 * Save the original (uncompleted) word
	 */
	free(tk_original);
	tk_original = ecalloc(cp-word+1, sizeof (char));
	(void) strncpy(tk_original, word, cp-word);
	/*
	 * Get the expanded filename.
	 * This may result in a single filename, or
	 * a blank-separated list of filenames.
	 */
	c = *cp;
	*cp = '\0';
	if (*word != openquote) {
		tk_text = fcomplete(word);
	} else {
		char *qword = shell_quote(word+1);
		if (qword == NULL)
			tk_text = fcomplete(word+1);
		else
			tk_text = fcomplete(qword);
		free(qword);
	}
	*cp = c;
}

/*
 * Return the next word in the current completion list.
 */
static char *
next_compl(int action, char *prev)
{
	switch (action) {
	case EC_F_COMPLETE:
		return (forw_textlist(&tk_tlist, prev));
	case EC_B_COMPLETE:
		return (back_textlist(&tk_tlist, prev));
	}
	/* Cannot happen */
	return ("?");
}

/*
 * Complete the filename before (or under) the cursor.
 * cmd_complete may be called multiple times.  The global in_completion
 * remembers whether this call is the first time (create the list),
 * or a subsequent time (step thru the list).
 */
static int
cmd_complete(int action)
{
	char *s;

	if (!in_completion || action == EC_EXPAND) {
		/*
		 * Expand the word under the cursor and
		 * use the first word in the expansion
		 * (or the entire expansion if we're doing EC_EXPAND).
		 */
		init_compl();
		if (tk_text == NULL) {
			ring_bell();
			return (CC_OK);
		}
		if (action == EC_EXPAND) {
			/*
			 * Use the whole list.
			 */
			tk_trial = tk_text;
		} else {
			/*
			 * Use the first filename in the list.
			 */
			in_completion = 1;
			init_textlist(&tk_tlist, tk_text);
			tk_trial = next_compl(action, NULL);
		}
	} else {
		/*
		 * We already have a completion list.
		 * Use the next/previous filename from the list.
		 */
		tk_trial = next_compl(action, tk_trial);
	}

	/*
	 * Remove the original word, or the previous trial completion.
	 */
	while (cp > tk_ipoint)
		(void) cmd_erase();

	if (tk_trial == NULL) {
		/*
		 * There are no more trial completions.
		 * Insert the original (uncompleted) filename.
		 */
		in_completion = 0;
		if (cmd_istr(tk_original) != CC_OK)
			goto fail;
	} else {
		/*
		 * Insert trial completion.
		 */
		if (cmd_istr(tk_trial) != CC_OK)
			goto fail;
		/*
		 * If it is a directory, append a slash.
		 */
		if (is_dir(tk_trial)) {
			if (cp > cmdbuf && cp[-1] == closequote)
				(void) cmd_erase();
			s = lgetenv("LESSSEPARATOR");
			if (s == NULL)
				s = "/";
			if (cmd_istr(s) != CC_OK)
				goto fail;
		}
	}

	return (CC_OK);

fail:
	in_completion = 0;
	ring_bell();
	return (CC_OK);
}

/*
 * Process a single character of a multi-character command, such as
 * a number, or the pattern of a search command.
 * Returns:
 *	CC_OK		The char was accepted.
 *	CC_QUIT		The char requests the command to be aborted.
 *	CC_ERROR	The char could not be accepted due to an error.
 */
int
cmd_char(int c)
{
	int action;
	int len;

	if (!utf_mode) {
		cmd_mbc_buf[0] = c & 0xff;
		len = 1;
	} else {
		/* Perform strict validation in all possible cases.  */
		if (cmd_mbc_buf_len == 0) {
retry:
			cmd_mbc_buf_index = 1;
			*cmd_mbc_buf = c & 0xff;
			if (isascii((unsigned char)c))
				cmd_mbc_buf_len = 1;
			else if (IS_UTF8_LEAD(c)) {
				cmd_mbc_buf_len = utf_len(c);
				return (CC_OK);
			} else {
				/* UTF8_INVALID or stray UTF8_TRAIL */
				ring_bell();
				return (CC_ERROR);
			}
		} else if (IS_UTF8_TRAIL(c)) {
			cmd_mbc_buf[cmd_mbc_buf_index++] = c & 0xff;
			if (cmd_mbc_buf_index < cmd_mbc_buf_len)
				return (CC_OK);
			if (!is_utf8_well_formed(cmd_mbc_buf)) {
				/*
				 * complete, but not well formed
				 * (non-shortest form), sequence
				 */
				cmd_mbc_buf_len = 0;
				ring_bell();
				return (CC_ERROR);
			}
		} else {
			/* Flush incomplete (truncated) sequence.  */
			cmd_mbc_buf_len = 0;
			ring_bell();
			/* Handle new char.  */
			goto retry;
		}

		len = cmd_mbc_buf_len;
		cmd_mbc_buf_len = 0;
	}

	if (literal) {
		/*
		 * Insert the char, even if it is a line-editing char.
		 */
		literal = 0;
		return (cmd_ichar(cmd_mbc_buf, len));
	}

	/*
	 * See if it is a line-editing character.
	 */
	if (in_mca() && len == 1) {
		action = cmd_edit(c);
		switch (action) {
		case CC_OK:
		case CC_QUIT:
			return (action);
		case CC_PASS:
			break;
		}
	}

	/*
	 * Insert the char into the command buffer.
	 */
	return (cmd_ichar(cmd_mbc_buf, len));
}

/*
 * Return the number currently in the command buffer.
 */
off_t
cmd_int(long *frac)
{
	char *p;
	off_t n = 0;
	int err;

	for (p = cmdbuf; *p >= '0' && *p <= '9'; p++)
		n = (n * 10) + (*p - '0');
	*frac = 0;
	if (*p++ == '.') {
		*frac = getfraction(&p, NULL, &err);
		/* {{ do something if err is set? }} */
	}
	return (n);
}

/*
 * Return a pointer to the command buffer.
 */
char *
get_cmdbuf(void)
{
	return (cmdbuf);
}

/*
 * Return the last (most recent) string in the current command history.
 */
char *
cmd_lastpattern(void)
{
	if (curr_mlist == NULL)
		return (NULL);
	return (curr_mlist->curr_mp->prev->string);
}

/*
 * Get the name of the history file.
 */
static char *
histfile_name(void)
{
	char *home;
	char *name;

	/* See if filename is explicitly specified by $LESSHISTFILE. */
	name = lgetenv("LESSHISTFILE");
	if (name != NULL && *name != '\0') {
		if (strcmp(name, "-") == 0 || strcmp(name, "/dev/null") == 0)
			/* $LESSHISTFILE == "-" means don't use history file */
			return (NULL);
		return (estrdup(name));
	}

	/* Otherwise, file is in $HOME if enabled. */
	if (strcmp(LESSHISTFILE, "-") == 0)
		return (NULL);
	home = lgetenv("HOME");
	if (home == NULL || *home == '\0') {
		return (NULL);
	}
	return (easprintf("%s/%s", home, LESSHISTFILE));
}

/*
 * Initialize history from a .lesshist file.
 */
void
init_cmdhist(void)
{
	struct mlist *ml = NULL;
	char line[CMDBUF_SIZE];
	char *filename;
	FILE *f;
	char *p;

	if (secure)
		return;
	filename = histfile_name();
	if (filename == NULL)
		return;
	f = fopen(filename, "r");
	free(filename);
	if (f == NULL)
		return;
	if (fgets(line, sizeof (line), f) == NULL ||
	    strncmp(line, HISTFILE_FIRST_LINE,
	    strlen(HISTFILE_FIRST_LINE)) != 0) {
		(void) fclose(f);
		return;
	}
	while (fgets(line, sizeof (line), f) != NULL) {
		for (p = line; *p != '\0'; p++) {
			if (*p == '\n' || *p == '\r') {
				*p = '\0';
				break;
			}
		}
		if (strcmp(line, HISTFILE_SEARCH_SECTION) == 0)
			ml = &mlist_search;
		else if (strcmp(line, HISTFILE_SHELL_SECTION) == 0) {
			ml = &mlist_shell;
		} else if (*line == '"') {
			if (ml != NULL)
				cmd_addhist(ml, line+1);
		}
	}
	(void) fclose(f);
}

/*
 *
 */
static void
save_mlist(struct mlist *ml, FILE *f)
{
	int histsize = 0;
	int n;
	char *s;

	s = lgetenv("LESSHISTSIZE");
	if (s != NULL)
		histsize = atoi(s);
	if (histsize == 0)
		histsize = 100;

	ml = ml->prev;
	for (n = 0; n < histsize; n++) {
		if (ml->string == NULL)
			break;
		ml = ml->prev;
	}
	for (ml = ml->next; ml->string != NULL; ml = ml->next)
		(void) fprintf(f, "\"%s\n", ml->string);
}

/*
 *
 */
void
save_cmdhist(void)
{
	char *filename;
	FILE *f;
	int modified = 0;
	int do_chmod = 1;
	struct stat statbuf;
	int r;

	if (secure)
		return;
	if (mlist_search.modified)
		modified = 1;
	if (mlist_shell.modified)
		modified = 1;
	if (!modified)
		return;
	filename = histfile_name();
	if (filename == NULL)
		return;
	f = fopen(filename, "w");
	free(filename);
	if (f == NULL)
		return;

	/* Make history file readable only by owner. */
	r = fstat(fileno(f), &statbuf);
	if (r == -1 || !S_ISREG(statbuf.st_mode))
		/* Don't chmod if not a regular file. */
		do_chmod = 0;
	if (do_chmod)
		(void) fchmod(fileno(f), 0600);

	(void) fprintf(f, "%s\n", HISTFILE_FIRST_LINE);

	(void) fprintf(f, "%s\n", HISTFILE_SEARCH_SECTION);
	save_mlist(&mlist_search, f);

	(void) fprintf(f, "%s\n", HISTFILE_SHELL_SECTION);
	save_mlist(&mlist_shell, f);

	(void) fclose(f);
}