files.c

/* $Id$ */
/**************************************************************************
 *   files.c                                                              *
 *                                                                        *
 *   Copyright (C) 1999-2004 Chris Allegretta                             *
 *   This program is free software; you can redistribute it and/or modify *
 *   it under the terms of the GNU General Public License as published by *
 *   the Free Software Foundation; either version 2, or (at your option)  *
 *   any later version.                                                   *
 *                                                                        *
 *   This program is distributed in the hope that it will be useful,      *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of       *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
 *   GNU General Public License for more details.                         *
 *                                                                        *
 *   You should have received a copy of the GNU General Public License    *
 *   along with this program; if not, write to the Free Software          *
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.            *
 *                                                                        *
 **************************************************************************/

#include "config.h"

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <utime.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
#include <pwd.h>
#include <assert.h>
#include "proto.h"
#include "nano.h"

/* Set a default value for PATH_MAX, so we can use it below in lines
 * like "path = getcwd(NULL, PATH_MAX + 1);". */
#ifndef PATH_MAX
#define PATH_MAX -1
#endif

/* What happens when there is no file to open? aiee! */
void new_file(void)
{
    fileage = make_new_node(NULL);
    fileage->data = charalloc(1);
    fileage->data[0] = '\0';
    filebot = fileage;
    edittop = fileage;
    current = fileage;
    current_x = 0;
    totlines = 1;
    totsize = 0;

#ifdef ENABLE_COLOR
    update_color();
    if (ISSET(COLOR_SYNTAX))
	edit_refresh();
#endif
}

/* We make a new line of text from buf.  buf is length len.  If
 * first_line_ins is TRUE, then we put the new line at the top of the
 * file.  Otherwise, we assume prev is the last line of the file, and
 * put our line after prev. */
filestruct *read_line(char *buf, filestruct *prev, bool *first_line_ins,
	size_t len)
{
    filestruct *fileptr = (filestruct *)nmalloc(sizeof(filestruct));

    /* Convert nulls to newlines.  len is the string's real length
     * here. */
    unsunder(buf, len);

    assert(strlen(buf) == len);

    fileptr->data = mallocstrcpy(NULL, buf);

#ifndef NANO_SMALL
    /* If it's a DOS file (CR LF), and file conversion isn't disabled,
     * strip out the CR part. */
    if (!ISSET(NO_CONVERT) && len > 0 && buf[len - 1] == '\r') {
	fileptr->data[len - 1] = '\0';
	totsize--;
    }
#endif

    if (*first_line_ins || fileage == NULL) {
	/* Special case: we're inserting with the cursor on the first
	 * line. */
	fileptr->prev = NULL;
	fileptr->next = fileage;
	fileptr->lineno = 1;
	if (*first_line_ins) {
	    *first_line_ins = FALSE;
	    /* If we're inserting into the first line of the file, then
	     * we want to make sure that our edit buffer stays on the
	     * first line and that fileage stays up to date. */
	    edittop = fileptr;
	} else
	    filebot = fileptr;
	fileage = fileptr;
    } else {
	assert(prev != NULL);
	fileptr->prev = prev;
	fileptr->next = NULL;
	fileptr->lineno = prev->lineno + 1;
	prev->next = fileptr;
    }

    return fileptr;
}

/* Load a file into the edit buffer.  This takes data from the file
 * struct. */
void load_file(void)
{
    current = fileage;

#ifdef ENABLE_MULTIBUFFER
    /* Add a new entry to the open_files structure. */
    add_open_file(FALSE);

    /* Reinitialize the shortcut list. */
    shortcut_init(FALSE);
#endif
}

void read_file(FILE *f, const char *filename)
{
    size_t num_lines = 0;
	/* The number of lines in the file. */
    size_t len = 0;
	/* The length of the current line of the file. */
    size_t i = 0;
	/* The position in the current line of the file. */
    size_t bufx = 128;
	/* The size of each chunk of the file that we read. */
    char input = '\0';
	/* The current input character. */
    char *buf;
	/* The buffer where we store chunks of the file. */
    filestruct *fileptr = current;
	/* The current line of the file. */
    bool first_line_ins = FALSE;
	/* Whether we're inserting with the cursor on the first line. */
    int input_int;
	/* The current value we read from the file, whether an input
	 * character or EOF. */
#ifndef NANO_SMALL
    int fileformat = 0;
	/* 0 = *nix, 1 = DOS, 2 = Mac, 3 = both DOS and Mac. */
#endif

    buf = charalloc(bufx);
    buf[0] = '\0';

    if (current != NULL) {
	if (current == fileage)
	    first_line_ins = TRUE;
	else
	    fileptr = current->prev;
    }

    /* For the assertion in read_line(), it must be true that if current
     * is NULL, then so is fileage. */
    assert(current != NULL || fileage == NULL);

#ifndef NANO_SMALL
    /* Clear the DOS and Mac file format flags, since we don't know
     * which file format we have yet. */
    UNSET(DOS_FILE);
    UNSET(MAC_FILE);
#endif

    /* Read the entire file into the file struct. */
    while ((input_int = getc(f)) != EOF) {
	input = (char)input_int;

	/* If it's a *nix file (LF) or a DOS file (CR LF), and file
	 * conversion isn't disabled, handle it! */
	if (input == '\n') {

#ifndef NANO_SMALL
	    /* If there's a CR before the LF, set fileformat to DOS if
	     * we currently think this is a *nix file, or to both if we
	     * currently think it's a Mac file. */
	    if (!ISSET(NO_CONVERT) && i > 0 && buf[i - 1] == '\r' &&
		(fileformat == 0 || fileformat == 2))
		fileformat++;
#endif

	    /* Read in the line properly. */
	    fileptr = read_line(buf, fileptr, &first_line_ins, len);

	    /* Reset the line length in preparation for the next
	     * line. */
	    len = 0;

	    num_lines++;
	    buf[0] = '\0';
	    i = 0;
#ifndef NANO_SMALL
	/* If it's a Mac file (CR without an LF), and file conversion
	 * isn't disabled, handle it! */
	} else if (!ISSET(NO_CONVERT) && i > 0 && buf[i - 1] == '\r') {

	    /* If we currently think the file is a *nix file, set
	     * fileformat to Mac.  If we currently think the file is a
	     * DOS file, set fileformat to both DOS and Mac. */
	    if (fileformat == 0 || fileformat == 1)
		fileformat += 2;

	    /* Read in the line properly. */
	    fileptr = read_line(buf, fileptr, &first_line_ins, len);

	    /* Reset the line length in preparation for the next line.
	     * Since we've already read in the next character, reset it
	     * to 1 instead of 0. */
	    len = 1;

	    num_lines++;
	    totsize++;
	    buf[0] = input;
	    buf[1] = '\0';
	    i = 1;
#endif
	} else {
	    /* Calculate the total length of the line.  It might have
	     * nulls in it, so we can't just use strlen() here. */
	    len++;

	    /* Now we allocate a bigger buffer 128 characters at a time.
	     * If we allocate a lot of space for one line, we may indeed
	     * have to use a buffer this big later on, so we don't
	     * decrease it at all.  We do free it at the end, though. */
	    if (i >= bufx - 1) {
		bufx += 128;
		buf = charealloc(buf, bufx);
	    }
	    buf[i] = input;
	    buf[i + 1] = '\0';
	    i++;
	}
	totsize++;
    }

    /* This conditional duplicates previous read_byte() behavior.
     * Perhaps this could use some better handling. */
    if (ferror(f))
	nperror(filename);
    fclose(f);

#ifndef NANO_SMALL
    /* If file conversion isn't disabled and the last character in this
     * file is a CR, read it in properly as a Mac format line. */
    if (len == 0 && !ISSET(NO_CONVERT) && input == '\r') {
	buf[0] = input;
	buf[1] = '\0';
	len = 1;
    }
#endif

    /* Did we not get a newline and still have stuff to do? */
    if (len > 0) {
#ifndef NANO_SMALL
	/* If file conversion isn't disabled and the last character in
	 * this file is a CR, set fileformat to Mac if we currently
	 * think the file is a *nix file, or to both DOS and Mac if we
	 * currently think the file is a DOS file. */
	if (!ISSET(NO_CONVERT) && buf[len - 1] == '\r' &&
		(fileformat == 0 || fileformat == 1))
	    fileformat += 2;
#endif

	/* Read in the last line properly. */
	fileptr = read_line(buf, fileptr, &first_line_ins, len);
	num_lines++;
	totsize++;
    }
    free(buf);

    /* If we didn't get a file and we don't already have one, make a new
     * file. */
    if (totsize == 0 || fileptr == NULL)
	new_file();

    /* Did we try to insert a file of 0 bytes? */
    if (num_lines != 0) {
	if (current != NULL) {
	    fileptr->next = current;
	    current->prev = fileptr;
	    renumber(current);
	    current_x = 0;
	    placewewant = 0;
	} else if (fileptr->next == NULL) {
	    filebot = fileptr;
	    new_magicline();
	    totsize--;
	}
    }

#ifndef NANO_SMALL
    if (fileformat == 3)
	statusbar(
		P_("Read %lu line (Converted from DOS and Mac format)",
		"Read %lu lines (Converted from DOS and Mac format)",
		(unsigned long)num_lines), (unsigned long)num_lines);
    else if (fileformat == 2) {
	SET(MAC_FILE);
	statusbar(P_("Read %lu line (Converted from Mac format)",
		"Read %lu lines (Converted from Mac format)",
		(unsigned long)num_lines), (unsigned long)num_lines);
    } else if (fileformat == 1) {
	SET(DOS_FILE);
	statusbar(P_("Read %lu line (Converted from DOS format)",
		"Read %lu lines (Converted from DOS format)",
		(unsigned long)num_lines), (unsigned long)num_lines);
    } else
#endif
	statusbar(P_("Read %lu line", "Read %lu lines",
		(unsigned long) num_lines),(unsigned long)num_lines);

    totlines += num_lines;
}

/* Open the file (and decide if it exists).  If newfie is TRUE, display
 * "New File" if the file is missing.  Otherwise, say "[filename] not
 * found".
 *
 * Return -2 if we say "New File".  Otherwise, -1 if the file isn't
 * opened, 0 otherwise.  The file might still have an error while
 * reading with a 0 return value.  *f is set to the opened file. */
int open_file(const char *filename, bool newfie, FILE **f)
{
    int fd;
    struct stat fileinfo;

    assert(f != NULL);
    if (filename == NULL || filename[0] == '\0' ||
	    stat(filename, &fileinfo) == -1) {
	if (newfie) {
	    statusbar(_("New File"));
	    return -2;
	}
	statusbar(_("\"%s\" not found"), filename);
	return -1;
    } else if (S_ISDIR(fileinfo.st_mode) || S_ISCHR(fileinfo.st_mode) ||
		S_ISBLK(fileinfo.st_mode)) {
	/* Don't open character or block files.  Sorry, /dev/sndstat! */
	statusbar(S_ISDIR(fileinfo.st_mode) ? _("\"%s\" is a directory") :
			_("File \"%s\" is a device file"), filename);
	return -1;
    } else if ((fd = open(filename, O_RDONLY)) == -1) {
	statusbar(_("Error reading %s: %s"), filename, strerror(errno));
 	return -1;
     } else {
	/* File is A-OK. */
	*f = fdopen(fd, "rb"); /* Binary for our own line-end munging */

	if (*f == NULL) {
	    statusbar(_("Error reading %s: %s"), filename, strerror(errno));
	    close(fd);
	} else
	    statusbar(_("Reading File"));
    }
    return 0;
}

/* This function will return the name of the first available extension
 * of a filename (starting with filename.save, then filename.save.1,
 * etc.).  Memory is allocated for the return value.  If no writable
 * extension exists, we return "". */
char *get_next_filename(const char *name)
{
    int i = 0;
    char *buf;
    size_t namelen = strlen(name);

    buf = charalloc(namelen + num_of_digits(INT_MAX) + 7);
    strcpy(buf, name);
    strcpy(buf + namelen, ".save");
    namelen += 5;

    while (TRUE) {
	struct stat fs;

	if (stat(buf, &fs) == -1)
	    return buf;
	if (i == INT_MAX)
	    break;

	i++;
	sprintf(buf + namelen, ".%d", i);
    }

    /* We get here only if there is no possible save file. */
    null_at(&buf, 0);
    return buf;
}

#ifndef NANO_SMALL
void execute_command(const char *command)
{
#ifdef ENABLE_MULTIBUFFER
    if (ISSET(MULTIBUFFER)) {
	/* Update the current entry in the open_files structure. */
	add_open_file(TRUE);
	new_file();
	UNSET(MODIFIED);
	UNSET(MARK_ISSET);
    }
#endif /* ENABLE_MULTIBUFFER */
    open_pipe(command);
#ifdef ENABLE_MULTIBUFFER
    /* Add this new entry to the open_files structure. */
    if (ISSET(MULTIBUFFER))
	load_file();
#endif /* ENABLE_MULTIBUFFER */
}
#endif /* !NANO_SMALL */

/* name is a file name to open.  We make a new buffer if necessary, then
 * open and read the file. */
void load_buffer(const char *name)
{
    bool new_buffer = fileage == NULL
#ifdef ENABLE_MULTIBUFFER
	 || ISSET(MULTIBUFFER)
#endif
	;
	/* new_buffer says whether we load to this buffer or a new one.
	 * If new_buffer is TRUE, we display "New File" if the file is
	 * not found, and if it is found we set filename and add a new
	 * open_files entry. */
    FILE *f;
    int rc;
	/* rc == -2 means that the statusbar displayed "New File".  -1
	 * means that the open failed.  0 means success. */

#ifndef DISABLE_OPERATINGDIR
    if (check_operating_dir(name, FALSE)) {
	statusbar(_("Can't insert file from outside of %s"), operating_dir);
	return;
    }
#endif

#ifdef ENABLE_MULTIBUFFER
    /* Update the current entry in the open_files structure. */
    add_open_file(TRUE);
#endif

    rc = open_file(name, new_buffer, &f);

#ifdef ENABLE_MULTIBUFFER
    if (rc != -1 && ISSET(MULTIBUFFER)) {
	UNSET(MODIFIED);
#ifndef NANO_SMALL
	UNSET(MARK_ISSET);
#endif
    }
#endif

    if (rc != -1 && new_buffer) {
	filename = mallocstrcpy(filename, name);
	new_file();
    }

    if (rc == 0) {
	read_file(f, filename);
#ifndef NANO_SMALL
	stat(filename, &originalfilestat);
#endif
    }

    /* Add this new entry to the open_files structure if we have
     * multibuffer support, or to the main filestruct if we don't. */
    if (rc != -1 && new_buffer)
	load_file();
}

void do_insertfile(
#ifndef NANO_SMALL
	bool execute
#else
	void
#endif
	)
{
    int i;
    const char *msg;
    char *ans = mallocstrcpy(NULL, "");
	/* The last answer the user typed on the statusbar. */

#ifndef DISABLE_WRAPPING
    wrap_reset();
#endif

    while (TRUE) {
#ifndef NANO_SMALL
	if (execute) {
#ifdef ENABLE_MULTIBUFFER
	    if (ISSET(MULTIBUFFER))
		msg = N_("Command to execute in new buffer [from %s] ");
	    else
#endif
		msg = N_("Command to execute [from %s] ");
	} else {
#endif
#ifdef ENABLE_MULTIBUFFER
	    if (ISSET(MULTIBUFFER)) {
		msg = N_("File to insert into new buffer [from %s] ");
	    } else
#endif
		msg = N_("File to insert [from %s] ");
#ifndef NANO_SMALL
	}
#endif

	i = statusq(TRUE,
#ifndef NANO_SMALL
		execute ? extcmd_list :
#endif
		insertfile_list, ans,
#ifndef NANO_SMALL
		NULL,
#endif
		_(msg),
#ifndef DISABLE_OPERATINGDIR
		operating_dir != NULL && strcmp(operating_dir, ".") != 0 ?
		operating_dir :
#endif
		"./");

	if (i < 0) {
	    statusbar(_("Cancelled"));
	    break;
	} else {
	    size_t old_current_x = current_x;
	    size_t old_pww = placewewant;

	    ans = mallocstrcpy(ans, answer);

#if !defined(NANO_SMALL) && defined(ENABLE_MULTIBUFFER)
	    if (i == TOGGLE_MULTIBUFFER_KEY) {
		/* Don't allow toggling if we're in view mode. */
		if (!ISSET(VIEW_MODE))
		    TOGGLE(MULTIBUFFER);
		continue;
	    }
#endif

#ifndef DISABLE_BROWSER
	    if (i == NANO_TOFILES_KEY) {
		char *tmp = do_browse_from(answer);

		if (tmp == NULL)
		    continue;
		free(answer);
		answer = tmp;

		/* We have a file now.  Get out of the statusbar prompt
		 * cleanly. */
		statusq_abort();
	    }
#endif

#ifndef NANO_SMALL
	    if (i == NANO_TOOTHERINSERT_KEY) {
		execute = !execute;
		continue;
	    }

	    if (execute)
		execute_command(answer);
	    else {
#endif
		answer = mallocstrassn(answer, real_dir_from_tilde(answer));
		load_buffer(answer);
#ifndef NANO_SMALL
	    }
#endif

#ifdef ENABLE_MULTIBUFFER
	    if (ISSET(MULTIBUFFER)) {
		/* Update the titlebar. */
		titlebar(NULL);

		/* Reinitialize the shortcut list. */
		shortcut_init(FALSE);
	    } else {
#endif
		/* Mark the file as modified. */
		set_modified();

		/* Restore the old cursor position. */
		current_x = old_current_x;
		placewewant = old_pww;
#ifdef ENABLE_MULTIBUFFER
	    }
#endif

	    /* Refresh the screen. */
	    edit_refresh();

	    break;
	}
    } /* while (TRUE) */

    free(ans);
}

void do_insertfile_void(void)
{
#ifdef ENABLE_MULTIBUFFER
    if (ISSET(VIEW_MODE) && !ISSET(MULTIBUFFER))
	statusbar(_("Key illegal in non-multibuffer mode"));
    else
#endif
	do_insertfile(
#ifndef NANO_SMALL
		FALSE
#endif
		);

    display_main_list();
}

#ifdef ENABLE_MULTIBUFFER
/* Create a new openfilestruct node. */
openfilestruct *make_new_opennode(openfilestruct *prevnode)
{
    openfilestruct *newnode = (openfilestruct *)nmalloc(sizeof(openfilestruct));

    newnode->filename = NULL;
    newnode->fileage = NULL;
    newnode->filebot = NULL;

    newnode->prev = prevnode;
    newnode->next = NULL;

    return newnode;
}

/* Splice a node into an existing openfilestruct. */
void splice_opennode(openfilestruct *begin, openfilestruct *newnode,
	openfilestruct *end)
{
    newnode->next = end;
    newnode->prev = begin;
    begin->next = newnode;
    if (end != NULL)
	end->prev = newnode;
}

/* Unlink a node from the rest of the openfilestruct. */
void unlink_opennode(const openfilestruct *fileptr)
{
    assert(fileptr != NULL);

    if (fileptr->prev != NULL)
	fileptr->prev->next = fileptr->next;

    if (fileptr->next != NULL)
	fileptr->next->prev = fileptr->prev;
}

/* Delete a node from the openfilestruct. */
void delete_opennode(openfilestruct *fileptr)
{
    if (fileptr != NULL) {
	if (fileptr->filename != NULL)
	    free(fileptr->filename);
	if (fileptr->fileage != NULL)
	    free_filestruct(fileptr->fileage);
	free(fileptr);
    }
}

/* Deallocate all memory associated with this and later files,
 * including the lines of text. */
void free_openfilestruct(openfilestruct *src)
{
    if (src != NULL) {
	while (src->next != NULL) {
	    src = src->next;
	    delete_opennode(src->prev);
#ifdef DEBUG
	    fprintf(stderr, "%s: free'd a node, YAY!\n", "delete_opennode()");
#endif
	}
	delete_opennode(src);
#ifdef DEBUG
	fprintf(stderr, "%s: free'd last node.\n", "delete_opennode()");
#endif
    }
}

/*
 * Add/update an entry to the open_files openfilestruct.  If update is
 * FALSE, a new entry is created; otherwise, the current entry is
 * updated.
 */
void add_open_file(bool update)
{
    openfilestruct *tmp;

    if (fileage == NULL || current == NULL || filename == NULL)
	return;

    /* if no entries, make the first one */
    if (open_files == NULL)
	open_files = make_new_opennode(NULL);

    else if (!update) {

	/* otherwise, if we're not updating, make a new entry for
	   open_files and splice it in after the current one */

#ifdef DEBUG
	fprintf(stderr, "filename is %s\n", open_files->filename);
#endif

	tmp = make_new_opennode(NULL);
	splice_opennode(open_files, tmp, open_files->next);
	open_files = open_files->next;
    }

    /* save current filename */
    open_files->filename = mallocstrcpy(open_files->filename, filename);

#ifndef NANO_SMALL
    /* save the file's stat */
    open_files->originalfilestat = originalfilestat;
#endif

    /* save current total number of lines */
    open_files->file_totlines = totlines;

    /* save current total size */
    open_files->file_totsize = totsize;

    /* save current x-coordinate position */
    open_files->file_current_x = current_x;

    /* save current y-coordinate position */
    open_files->file_current_y = current_y;

    /* save current place we want */
    open_files->file_placewewant = placewewant;

    /* save current line number */
    open_files->file_lineno = current->lineno;

    /* start with default modification status: unmodified, unmarked (if
       available), not in DOS format (if available), and not in Mac
       format (if available) */
    open_files->file_flags = 0;

    /* if we're updating, save current modification status, current
       marking status (if available), and current file format status (if
       available) */
    if (update) {
	if (ISSET(MODIFIED))
	    open_files->file_flags |= MODIFIED;
#ifndef NANO_SMALL
	if (ISSET(MARK_ISSET)) {
	    open_files->file_mark_beginbuf = mark_beginbuf;
	    open_files->file_mark_beginx = mark_beginx;
	    open_files->file_flags |= MARK_ISSET;
	}
	if (ISSET(DOS_FILE))
	    open_files->file_flags |= DOS_FILE;
	else if (ISSET(MAC_FILE))
	    open_files->file_flags |= MAC_FILE;
#endif
    }

    /* if we're not in view mode and not updating, the file contents
       might have changed, so save the filestruct; otherwise, don't */
    if (!(ISSET(VIEW_MODE) && !update)) {
	/* save current file buffer */
	open_files->fileage = fileage;
	open_files->filebot = filebot;
    }

#ifdef DEBUG
    fprintf(stderr, "filename is %s\n", open_files->filename);
#endif
}

/*
 * Read the current entry in the open_files structure and set up the
 * currently open file using that entry's information.
 */
void load_open_file(void)
{
    if (open_files == NULL)
	return;

    /* set up the filename, the file buffer, the total number of lines in
       the file, and the total file size */
    filename = mallocstrcpy(filename, open_files->filename);
#ifndef NANO_SMALL
    originalfilestat = open_files->originalfilestat;
#endif
    fileage = open_files->fileage;
    current = fileage;
    filebot = open_files->filebot;
    totlines = open_files->file_totlines;
    totsize = open_files->file_totsize;

    /* restore modification status */
    if (open_files->file_flags & MODIFIED)
	SET(MODIFIED);
    else
	UNSET(MODIFIED);

#ifndef NANO_SMALL
    /* restore marking status */
    if (open_files->file_flags & MARK_ISSET) {
	mark_beginbuf = open_files->file_mark_beginbuf;
	mark_beginx = open_files->file_mark_beginx;
	SET(MARK_ISSET);
    } else
	UNSET(MARK_ISSET);

    /* restore file format status */
    UNSET(DOS_FILE);
    UNSET(MAC_FILE);
    if (open_files->file_flags & DOS_FILE)
	SET(DOS_FILE);
    else if (open_files->file_flags & MAC_FILE)
	SET(MAC_FILE);
#endif

#ifdef ENABLE_COLOR
    update_color();
#endif

    /* restore full file position: line number, x-coordinate, y-
       coordinate, place we want */
    do_gotopos(open_files->file_lineno, open_files->file_current_x,
	open_files->file_current_y, open_files->file_placewewant);

    /* update the titlebar */
    clearok(topwin, FALSE);
    titlebar(NULL);
}

/*
 * Open the previous entry in the open_files structure.  If closing_file
 * is FALSE, update the current entry before switching from it.
 * Otherwise, we are about to close that entry, so don't bother doing
 * so.
 */
void open_prevfile(bool closing_file)
{
    if (open_files == NULL)
	return;

    /* if we're not about to close the current entry, update it before
       doing anything */
    if (!closing_file)
	add_open_file(TRUE);

    if (open_files->prev == NULL && open_files->next == NULL) {

	/* only one file open */
	if (!closing_file)
	    statusbar(_("No more open file buffers"));
	return;
    }

    if (open_files->prev != NULL) {
	open_files = open_files->prev;

#ifdef DEBUG
	fprintf(stderr, "filename is %s\n", open_files->filename);
#endif

    }

    else if (open_files->next != NULL) {

	/* if we're at the beginning, wrap around to the end */
	while (open_files->next != NULL)
	    open_files = open_files->next;

#ifdef DEBUG
	    fprintf(stderr, "filename is %s\n", open_files->filename);
#endif

    }

    load_open_file();

    statusbar(_("Switched to %s"),
      ((open_files->filename[0] == '\0') ? _("New Buffer") :
	open_files->filename));

#ifdef DEBUG
    dump_buffer(current);
#endif
}

void open_prevfile_void(void)
{
    open_prevfile(FALSE);
}

/*
 * Open the next entry in the open_files structure.  If closing_file is
 * FALSE, update the current entry before switching from it.  Otherwise,
 * we are about to close that entry, so don't bother doing so.
 */
void open_nextfile(bool closing_file)
{
    if (open_files == NULL)
	return;

    /* if we're not about to close the current entry, update it before
       doing anything */
    if (!closing_file)
	add_open_file(TRUE);

    if (open_files->prev == NULL && open_files->next == NULL) {

	/* only one file open */
	if (!closing_file)
	    statusbar(_("No more open file buffers"));
	return;
    }

    if (open_files->next != NULL) {
	open_files = open_files->next;

#ifdef DEBUG
	fprintf(stderr, "filename is %s\n", open_files->filename);
#endif

    }
    else if (open_files->prev != NULL) {

	/* if we're at the end, wrap around to the beginning */
	while (open_files->prev != NULL) {
	    open_files = open_files->prev;

#ifdef DEBUG
	    fprintf(stderr, "filename is %s\n", open_files->filename);
#endif

	}
    }

    load_open_file();

    statusbar(_("Switched to %s"),
      ((open_files->filename[0] == '\0') ? _("New Buffer") :
	open_files->filename));

#ifdef DEBUG
    dump_buffer(current);
#endif
}

void open_nextfile_void(void)
{
    open_nextfile(FALSE);
}

/*
 * Delete an entry from the open_files filestruct.  After deletion of an
 * entry, the next or previous entry is opened, whichever is found first.
 * Return TRUE on success or FALSE on error.
 */
bool close_open_file(void)
{
    openfilestruct *tmp;

    if (open_files == NULL)
	return FALSE;

    /* make sure open_files->fileage and fileage, and open_files->filebot
       and filebot, are in sync; they might not be if lines have been cut
       from the top or bottom of the file */
    open_files->fileage = fileage;
    open_files->filebot = filebot;

    tmp = open_files;
    if (open_files->next != NULL)
	open_nextfile(TRUE);
    else if (open_files->prev != NULL)
	open_prevfile(TRUE);
    else
	return FALSE;

    unlink_opennode(tmp);
    delete_opennode(tmp);

    shortcut_init(FALSE);
    display_main_list();
    return TRUE;
}
#endif /* ENABLE_MULTIBUFFER */

#if !defined(DISABLE_SPELLER) || !defined(DISABLE_OPERATINGDIR) || !defined(NANO_SMALL)
/*
 * When passed "[relative path]" or "[relative path][filename]" in
 * origpath, return "[full path]" or "[full path][filename]" on success,
 * or NULL on error.  This is still done if the file doesn't exist but
 * the relative path does (since the file could exist in memory but not
 * yet on disk); it is not done if the relative path doesn't exist (since
 * the first call to chdir() will fail then).
 */
char *get_full_path(const char *origpath)
{
    char *newpath = NULL, *last_slash, *d_here, *d_there, *d_there_file, tmp;
    int path_only, last_slash_index;
    struct stat fileinfo;
    char *expanded_origpath;

    /* first, get the current directory, and tack a slash onto the end of
       it, unless it turns out to be "/", in which case leave it alone */

    d_here = getcwd(NULL, PATH_MAX + 1);

    if (d_here != NULL) {

	align(&d_here);
	if (strcmp(d_here, "/") != 0) {
	    d_here = charealloc(d_here, strlen(d_here) + 2);
	    strcat(d_here, "/");
	}

	/* stat origpath; if stat() fails, assume that origpath refers to
	   a new file that hasn't been saved to disk yet (i. e. set
	   path_only to 0); if stat() succeeds, set path_only to 0 if
	   origpath doesn't refer to a directory, or to 1 if it does */
	path_only = !stat(origpath, &fileinfo) && S_ISDIR(fileinfo.st_mode);

	expanded_origpath = real_dir_from_tilde(origpath);
	/* save the value of origpath in both d_there and d_there_file */
	d_there = mallocstrcpy(NULL, expanded_origpath);
	d_there_file = mallocstrcpy(NULL, expanded_origpath);
	free(expanded_origpath);

	/* if we have a path but no filename, tack slashes onto the ends
	   of both d_there and d_there_file, if they don't end in slashes
	   already */
	if (path_only) {
	    tmp = d_there[strlen(d_there) - 1];
	    if (tmp != '/') {
		d_there = charealloc(d_there, strlen(d_there) + 2);
		strcat(d_there, "/");
		d_there_file = charealloc(d_there_file, strlen(d_there_file) + 2);
		strcat(d_there_file, "/");
	    }
	}

	/* search for the last slash in d_there */
	last_slash = strrchr(d_there, '/');

	/* if we didn't find one, copy d_here into d_there; all data is
	   then set up */
	if (last_slash == NULL)
	    d_there = mallocstrcpy(d_there, d_here);
	else {
	    /* otherwise, remove all non-path elements from d_there
	       (i. e. everything after the last slash) */
	    last_slash_index = strlen(d_there) - strlen(last_slash);
	    null_at(&d_there, last_slash_index + 1);

	    /* and remove all non-file elements from d_there_file (i. e.
	       everything before and including the last slash); if we
	       have a path but no filename, don't do anything */
	    if (!path_only) {
		last_slash = strrchr(d_there_file, '/');
		last_slash++;
		strcpy(d_there_file, last_slash);
		align(&d_there_file);
	    }

	    /* now go to the path specified in d_there */
	    if (chdir(d_there) != -1) {
		/* get the full pathname, and save it back in d_there,
		   tacking a slash on the end if we have a path but no
		   filename; if the saving fails, get out */

		free(d_there);

		d_there = getcwd(NULL, PATH_MAX + 1);

		align(&d_there);
		if (d_there != NULL) {

		    /* add a slash to d_there, unless it's "/", in which
		       case we don't need it */
		    if (strcmp(d_there, "/") != 0) {
			d_there = charealloc(d_there, strlen(d_there) + 2);
			strcat(d_there, "/");
		    }
		}
		else
		    return NULL;
	    }

	    /* finally, go back to where we were before, d_here (no error
	       checking is done on this chdir(), because we can do
	       nothing if it fails) */
	    chdir(d_here);
	}
	
	/* all data is set up; fill in newpath */

	/* if we have a path and a filename, newpath = d_there +
	   d_there_file; otherwise, newpath = d_there */
	if (!path_only) {
	    newpath = charalloc(strlen(d_there) + strlen(d_there_file) + 1);
	    strcpy(newpath, d_there);
	    strcat(newpath, d_there_file);
	}
	else {
	    newpath = charalloc(strlen(d_there) + 1);
	    strcpy(newpath, d_there);
	}

	/* finally, clean up */
	free(d_there_file);
	free(d_there);
	free(d_here);
    }

    return newpath;
}
#endif /* !DISABLE_SPELLER || !DISABLE_OPERATINGDIR */

#ifndef DISABLE_SPELLER
/*
 * This function accepts a path and returns the full path (via
 * get_full_path()).  On error, if the path doesn't reference a
 * directory, or if the directory isn't writable, it returns NULL.
 */
char *check_writable_directory(const char *path)
{
    char *full_path = get_full_path(path);
    int writable;
    struct stat fileinfo;

    /* if get_full_path() failed, return NULL */
    if (full_path == NULL)
	return NULL;

    /* otherwise, stat() the full path to see if it's writable by the
       user; set writable to 1 if it is, or 0 if it isn't */
    writable = !stat(full_path, &fileinfo) && (fileinfo.st_mode & S_IWUSR);

    /* if the full path doesn't end in a slash (meaning get_full_path()
       found that it isn't a directory) or isn't writable, free full_path
       and return NULL */
    if (full_path[strlen(full_path) - 1] != '/' || writable == 0) {
	free(full_path);
	return NULL;
    }

    /* otherwise, return the full path */
    return full_path;
}

/*
 * This function accepts a directory name and filename prefix the same
 * way that tempnam() does, determines the location for its temporary
 * file the same way that tempnam() does, safely creates the temporary
 * file there via mkstemp(), and returns the name of the temporary file
 * the same way that tempnam() does.  It does not reference the value of
 * TMP_MAX because the total number of random filenames that it can
 * generate using one prefix is equal to 256**6, which is a sufficiently
 * large number to handle most cases.  Since the behavior after tempnam()
 * generates TMP_MAX random filenames is implementation-defined, my
 * implementation is to go on generating random filenames regardless of
 * it.
 */
char *safe_tempnam(const char *dirname, const char *filename_prefix)
{
    char *full_tempdir = NULL;
    const char *TMPDIR_env;
    int filedesc;

      /* if $TMPDIR is set and non-empty, set tempdir to it, run it through
         get_full_path(), and save the result in full_tempdir; otherwise,
         leave full_tempdir set to NULL */
    TMPDIR_env = getenv("TMPDIR");
    if (TMPDIR_env != NULL && TMPDIR_env[0] != '\0')
	full_tempdir = check_writable_directory(TMPDIR_env);

    /* if $TMPDIR is blank or isn't set, or isn't a writable
       directory, and dirname isn't NULL, try it; otherwise, leave
       full_tempdir set to NULL */
    if (full_tempdir == NULL && dirname != NULL)
	full_tempdir = check_writable_directory(dirname);

    /* if $TMPDIR is blank or isn't set, or if it isn't a writable
       directory, and dirname is NULL, try P_tmpdir instead */
    if (full_tempdir == NULL)
	full_tempdir = check_writable_directory(P_tmpdir);

    /* if P_tmpdir didn't work, use /tmp instead */
    if (full_tempdir == NULL) {
	full_tempdir = charalloc(6);
	strcpy(full_tempdir, "/tmp/");
    }

    full_tempdir = charealloc(full_tempdir, strlen(full_tempdir) + 12);

    /* like tempnam(), use only the first 5 characters of the prefix */
    strncat(full_tempdir, filename_prefix, 5);
    strcat(full_tempdir, "XXXXXX");
    filedesc = mkstemp(full_tempdir);

    /* if mkstemp succeeded, close the resulting file; afterwards, it'll be
       0 bytes long, so delete it; finally, return the filename (all that's
       left of it) */
    if (filedesc != -1) {
	close(filedesc);
	unlink(full_tempdir);
	return full_tempdir;
    }

    free(full_tempdir);
    return NULL;
}
#endif /* !DISABLE_SPELLER */

#ifndef DISABLE_OPERATINGDIR
/* Initialize full_operating_dir based on operating_dir. */
void init_operating_dir(void)
{
    assert(full_operating_dir == NULL);

    if (operating_dir == NULL)
	return;

    full_operating_dir = get_full_path(operating_dir);

    /* If get_full_path() failed or the operating directory is
     * inaccessible, unset operating_dir. */
    if (full_operating_dir == NULL || chdir(full_operating_dir) == -1) {
	free(full_operating_dir);
	full_operating_dir = NULL;
	free(operating_dir);
	operating_dir = NULL;
    }
}

/* Check to see if we're inside the operating directory.  Return 0 if we
 * are, or 1 otherwise.  If allow_tabcomp is nonzero, allow incomplete
 * names that would be matches for the operating directory, so that tab
 * completion will work. */
int check_operating_dir(const char *currpath, int allow_tabcomp)
{
    /* The char *full_operating_dir is global for mem cleanup.  It
     * should have already been initialized by init_operating_dir().
     * Also, a relative operating directory path will only be handled
     * properly if this is done. */

    char *fullpath;
    int retval = 0;
    const char *whereami1, *whereami2 = NULL;

    /* If no operating directory is set, don't bother doing anything. */
    if (operating_dir == NULL)
	return 0;

    assert(full_operating_dir != NULL);

    fullpath = get_full_path(currpath);

    /* fullpath == NULL means some directory in the path doesn't exist
     * or is unreadable.  If allow_tabcomp is zero, then currpath is
     * what the user typed somewhere.  We don't want to report a
     * non-existent directory as being outside the operating directory,
     * so we return 0.  If allow_tabcomp is nonzero, then currpath
     * exists, but is not executable.  So we say it isn't in the
     * operating directory. */
    if (fullpath == NULL)
	return allow_tabcomp;

    whereami1 = strstr(fullpath, full_operating_dir);
    if (allow_tabcomp)
	whereami2 = strstr(full_operating_dir, fullpath);

    /* If both searches failed, we're outside the operating directory.
     * Otherwise, check the search results; if the full operating
     * directory path is not at the beginning of the full current path
     * (for normal usage) and vice versa (for tab completion, if we're
     * allowing it), we're outside the operating directory. */
    if (whereami1 != fullpath && whereami2 != full_operating_dir)
	retval = 1;
    free(fullpath);	

    /* Otherwise, we're still inside it. */
    return retval;
}
#endif

#ifndef NANO_SMALL
void init_backup_dir(void)
{
    char *full_backup_dir;

    if (backup_dir == NULL)
	return;

    full_backup_dir = get_full_path(backup_dir);

    /* If get_full_path() failed or the backup directory is
     * inaccessible, unset backup_dir. */
    if (full_backup_dir == NULL ||
	full_backup_dir[strlen(full_backup_dir) - 1] != '/') {
	free(full_backup_dir);
	free(backup_dir);
	backup_dir = NULL;
    } else {
	free(backup_dir);
	backup_dir = full_backup_dir;
    }
}
#endif

/* Read from inn, write to out.  We assume inn is opened for reading,
 * and out for writing.  We return 0 on success, -1 on read error, -2 on
 * write error. */
int copy_file(FILE *inn, FILE *out)
{
    char buf[BUFSIZ];
    size_t charsread;
    int retval = 0;

    assert(inn != NULL && out != NULL);
    do {
	charsread = fread(buf, sizeof(char), BUFSIZ, inn);
	if (charsread == 0 && ferror(inn)) {
	    retval = -1;
	    break;
	}
	if (fwrite(buf, sizeof(char), charsread, out) < charsread) {
	    retval = -2;
	    break;
	}
    } while (charsread > 0);
    if (fclose(inn) == EOF)
	retval = -1;
    if (fclose(out) == EOF)
	retval = -2;
    return retval;
}

/* Write a file out.  If tmp is FALSE, we set the umask to disallow
 * anyone else from accessing the file, we don't set the global variable
 * filename to its name, and we don't print out how many lines we wrote
 * on the statusbar.
 *
 * tmp means we are writing a temporary file in a secure fashion.  We
 * use it when spell checking or dumping the file on an error.
 *
 * append == 1 means we are appending instead of overwriting.
 * append == 2 means we are prepending instead of overwriting.
 *
 * nonamechange means don't change the current filename.  It is ignored
 * if tmp is FALSE or if we're appending/prepending.
 *
 * Return -1 on error, 1 on success. */
int write_file(const char *name, int tmp, int append, int nonamechange)
{
    int retval = -1;
	/* Instead of returning in this function, you should always
	 * merely set retval and then goto cleanup_and_exit. */
    size_t lineswritten = 0;
    const filestruct *fileptr = fileage;
    int fd;
	/* The file descriptor we use. */
    mode_t original_umask = 0;
	/* Our umask, from when nano started. */
    int realexists;
	/* The result of stat().  TRUE if the file exists, FALSE
	 * otherwise.  If name is a link that points nowhere, realexists
	 * is FALSE. */
    struct stat st;
	/* The status fields filled in by stat(). */
    int anyexists;
	/* The result of lstat().  Same as realexists unless name is a
	 * link. */
    struct stat lst;
	/* The status fields filled in by lstat(). */
    char *realname;
	/* name after tilde expansion. */
    FILE *f;
	/* The actual file, realname, we are writing to. */
    char *tempname = NULL;
	/* The temp file name we write to on prepend. */

    assert(name != NULL);
    if (name[0] == '\0')
	return -1;
    if (!tmp)
	titlebar(NULL);

    realname = real_dir_from_tilde(name);

#ifndef DISABLE_OPERATINGDIR
    /* If we're writing a temporary file, we're probably going outside
     * the operating directory, so skip the operating directory test. */
    if (!tmp && check_operating_dir(realname, FALSE) != 0) {
	statusbar(_("Can't write outside of %s"), operating_dir);
	goto cleanup_and_exit;
    }
#endif

    anyexists = lstat(realname, &lst) != -1;
    /* New case: if the file exists, just give up. */
    if (tmp && anyexists)
	goto cleanup_and_exit;
    /* If NOFOLLOW_SYMLINKS is set, it doesn't make sense to prepend or
     * append to a symlink.  Here we warn about the contradiction. */
    if (ISSET(NOFOLLOW_SYMLINKS) && anyexists && S_ISLNK(lst.st_mode)) {
	statusbar(
		_("Cannot prepend or append to a symlink with --nofollow set"));
	goto cleanup_and_exit;
    }

    /* Save the state of file at the end of the symlink (if there is
     * one). */
    realexists = stat(realname, &st) != -1;

#ifndef NANO_SMALL
    /* We backup only if the backup toggle is set, the file isn't
     * temporary, and the file already exists.  Furthermore, if we
     * aren't appending, prepending, or writing a selection, we backup
     * only if the file has not been modified by someone else since nano
     * opened it. */
    if (ISSET(BACKUP_FILE) && !tmp && realexists != 0 &&
	(append != 0 || ISSET(MARK_ISSET) ||
	originalfilestat.st_mtime == st.st_mtime)) {

	FILE *backup_file;
	char *backupname;
	struct utimbuf filetime;
	int copy_status;

	/* Save the original file's access and modification times. */
	filetime.actime = originalfilestat.st_atime;
	filetime.modtime = originalfilestat.st_mtime;

	/* Open the original file to copy to the backup. */
	f = fopen(realname, "rb");
	if (f == NULL) {
	    statusbar(_("Error reading %s: %s"), realname,
		strerror(errno));
	    goto cleanup_and_exit;
	}

	/* If backup_dir is set, we set backupname to
	 * backup_dir/backupname~, where backupnae is the canonicalized
	 * absolute pathname of realname with every '/' replaced with a
	 * '!'.  This means that /home/foo/file is backed up in
	 * backup_dir/!home!foo!file~. */
	if (backup_dir != NULL) {
	    char *canon_realname = get_full_path(realname);
	    size_t i;

	    if (canon_realname == NULL)
		/* If get_full_path() failed, we don't have a
		 * canonicalized absolute pathname, so just use the
		 * filename portion of the pathname.  We use tail() so
		 * that e.g. ../backupname will be backed up in
		 * backupdir/backupname~ instead of
		 * backupdir/../backupname~. */
		canon_realname = mallocstrcpy(NULL, tail(realname));
	    else {
		for (i = 0; canon_realname[i] != '\0'; i++) {
		    if (canon_realname[i] == '/')
			canon_realname[i] = '!';
		}
	    }

	    backupname = charalloc(strlen(backup_dir) +
		strlen(canon_realname) + 2);
	    sprintf(backupname, "%s%s~", backup_dir, canon_realname);
	    free(canon_realname);
	} else {
	    backupname = charalloc(strlen(realname) + 2);
	    sprintf(backupname, "%s~", realname);
	}

	/* Open the destination backup file.  Before we write to it, we
	 * set its permissions, so no unauthorized person can read it as
	 * we write. */
	backup_file = fopen(backupname, "wb");
	if (backup_file == NULL ||
		chmod(backupname, originalfilestat.st_mode) == -1) {
	    statusbar(_("Error writing %s: %s"), backupname, strerror(errno));
	    free(backupname);
	    if (backup_file != NULL)
		fclose(backup_file);
	    fclose(f);
	    goto cleanup_and_exit;
	}

#ifdef DEBUG
	fprintf(stderr, "Backing up %s to %s\n", realname, backupname);
#endif

	/* Copy the file. */
	copy_status = copy_file(f, backup_file);
	/* And set metadata. */
	if (copy_status != 0 || chown(backupname, originalfilestat.st_uid,
		originalfilestat.st_gid) == -1 ||
		utime(backupname, &filetime) == -1) {
	    free(backupname);
	    if (copy_status == -1)
		statusbar(_("Error reading %s: %s"), realname, strerror(errno));
	    else
		statusbar(_("Error writing %s: %s"), backupname,
			strerror(errno));
	    goto cleanup_and_exit;
	}
	free(backupname);
    }
#endif /* !NANO_SMALL */

    /* If NOFOLLOW_SYMLINKS and the file is a link, we aren't doing
     * prepend or append.  So we delete the link first, and just
     * overwrite. */
    if (ISSET(NOFOLLOW_SYMLINKS) && anyexists && S_ISLNK(lst.st_mode) &&
	unlink(realname) == -1) {
	statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	goto cleanup_and_exit;
    }

    original_umask = umask(0);
    umask(original_umask);

    /* If we create a temp file, we don't let anyone else access it.  We
     * create a temp file if tmp is TRUE or if we're prepending. */
    if (tmp || append == 2)
	umask(S_IRWXG | S_IRWXO);

    /* If we're prepending, copy the file to a temp file. */
    if (append == 2) {
	int fd_source;
	FILE *f_source = NULL;

	tempname = charalloc(strlen(realname) + 8);
	strcpy(tempname, realname);
	strcat(tempname, ".XXXXXX");
	fd = mkstemp(tempname);
	f = NULL;
	if (fd != -1) {
	    f = fdopen(fd, "wb");
	    if (f == NULL)
		close(fd);
	}
	if (f == NULL) {
	    statusbar(_("Error writing %s: %s"), tempname, strerror(errno));
	    unlink(tempname);
	    goto cleanup_and_exit;
	}

	fd_source = open(realname, O_RDONLY | O_CREAT);
	if (fd_source != -1) {
	    f_source = fdopen(fd_source, "rb");
	    if (f_source == NULL)
		close(fd_source);
	}
	if (f_source == NULL) {
	    statusbar(_("Error reading %s: %s"), realname, strerror(errno));
	    fclose(f);
	    unlink(tempname);
	    goto cleanup_and_exit;
	}

	if (copy_file(f_source, f) != 0) {
	    statusbar(_("Error writing %s: %s"), tempname, strerror(errno));
	    unlink(tempname);
	    goto cleanup_and_exit;
	}
    }

    /* Now open the file in place.  Use O_EXCL if tmp is TRUE.  This is
     * now copied from joe, because wiggy says so *shrug*. */
    fd = open(realname, O_WRONLY | O_CREAT |
	(append == 1 ? O_APPEND : (tmp ? O_EXCL : O_TRUNC)),
	S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);

    /* Set the umask back to the user's original value. */
    umask(original_umask);

    /* First, just give up if we couldn't even open the file. */
    if (fd == -1) {
	statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	/* tempname has been set only if we're prepending. */
	if (tempname != NULL)
	    unlink(tempname);
	goto cleanup_and_exit;
    }

    f = fdopen(fd, append == 1 ? "ab" : "wb");
    if (f == NULL) {
	statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	close(fd);
	goto cleanup_and_exit;
    }

    /* There might not be a magicline.  There won't be when writing out
     * a selection. */
    assert(fileage != NULL && filebot != NULL);
    while (fileptr != filebot) {
	size_t data_len = strlen(fileptr->data);
	size_t size;

	/* Newlines to nulls, just before we write to disk. */
	sunder(fileptr->data);

	size = fwrite(fileptr->data, sizeof(char), data_len, f);

	/* Nulls to newlines; data_len is the string's real length. */
	unsunder(fileptr->data, data_len);

	if (size < data_len) {
	    statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	    fclose(f);
	    goto cleanup_and_exit;
	}
#ifndef NANO_SMALL
	if (ISSET(DOS_FILE) || ISSET(MAC_FILE))
	    if (putc('\r', f) == EOF) {
		statusbar(_("Error writing %s: %s"), realname, strerror(errno));
		fclose(f);
		goto cleanup_and_exit;
	    }

	if (!ISSET(MAC_FILE))
#endif
	    if (putc('\n', f) == EOF) {
		statusbar(_("Error writing %s: %s"), realname, strerror(errno));
		fclose(f);
		goto cleanup_and_exit;
	    }

	fileptr = fileptr->next;
	lineswritten++;
    }

    /* If we're prepending, open the temp file, and append it to f. */
    if (append == 2) {
	int fd_source;
	FILE *f_source = NULL;

	fd_source = open(tempname, O_RDONLY | O_CREAT);
	if (fd_source != -1) {
	    f_source = fdopen(fd_source, "rb");
	    if (f_source == NULL)
		close(fd_source);
	}
	if (f_source == NULL) {
	    statusbar(_("Error reading %s: %s"), tempname, strerror(errno));
	    fclose(f);
	    goto cleanup_and_exit;
	}

	if (copy_file(f_source, f) == -1 || unlink(tempname) == -1) {
	    statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	    goto cleanup_and_exit;
	}
    } else if (fclose(f) == EOF) {
	statusbar(_("Error writing %s: %s"), realname, strerror(errno));
	unlink(tempname);
	goto cleanup_and_exit;
    }

    if (!tmp && append == 0) {
	if (!nonamechange) {
	    filename = mallocstrcpy(filename, realname);
#ifdef ENABLE_COLOR
	    update_color();
	    if (ISSET(COLOR_SYNTAX))
		edit_refresh();
#endif
	}

#ifndef NANO_SMALL
	/* Update originalfilestat to reference the file as it is now. */
	stat(filename, &originalfilestat);
#endif
	statusbar(P_("Wrote %u line", "Wrote %u lines", lineswritten),
		lineswritten);
	UNSET(MODIFIED);
	titlebar(NULL);
    }

    retval = 1;

  cleanup_and_exit:
    free(realname);
    free(tempname);
    return retval;
}

#ifndef NANO_SMALL
/* Write a marked selection from a file out.  First, set fileage and
 * filebot as the top and bottom of the mark, respectively.  Then call
 * write_file() with the values of name, temp, and append, and with
 * nonamechange set to TRUE so that we don't change the current
 * filename.  Finally, set fileage and filebot back to their old values
 * and return. */
int write_marked(const char *name, int tmp, int append)
{
    int retval = -1;
    filestruct *fileagebak = fileage;
    filestruct *filebotbak = filebot;
    bool old_modified = ISSET(MODIFIED);
	/* write_file() unsets the MODIFIED flag. */
    size_t topx;
	/* The column of the beginning of the mark. */
    char origchar;
	/* We replace the character at the end of the mark with '\0'.
	 * We save the original character, to restore it. */
    char *origcharloc;
	/* The location of the character we nulled. */

    /* Set fileage as the top of the mark, and filebot as the bottom. */
    if (current->lineno > mark_beginbuf->lineno ||
		(current->lineno == mark_beginbuf->lineno &&
		current_x > mark_beginx)) {
	fileage = mark_beginbuf;
	topx = mark_beginx;
	filebot = current;
	origcharloc = current->data + current_x;
    } else {
	fileage = current;
	topx = current_x;
	filebot = mark_beginbuf;
	origcharloc = mark_beginbuf->data + mark_beginx;
    }
    origchar = *origcharloc;
    *origcharloc = '\0';
    fileage->data += topx;

    /* If the line at filebot is blank, treat it as the magicline and
     * hence the end of the file.  Otherwise, treat the line after
     * filebot as the end of the file. */
    if (filebot->data[0] != '\0' && filebot->next != NULL)
	filebot = filebot->next;

    retval = write_file(name, tmp, append, TRUE);

    /* Now restore everything. */
    fileage->data -= topx;
    *origcharloc = origchar;
    fileage = fileagebak;
    filebot = filebotbak;
    if (old_modified)
	set_modified();

    return retval;
}
#endif /* !NANO_SMALL */

int do_writeout(bool exiting)
{
    int i;
    int retval = 0, append = 0;
    char *ans;
	/* The last answer the user typed on the statusbar. */
#ifdef NANO_EXTRA
    static bool did_cred = FALSE;
#endif

#if !defined(DISABLE_BROWSER) || !defined(DISABLE_MOUSE)
    currshortcut = writefile_list;
#endif

    if (exiting && filename[0] != '\0' && ISSET(TEMP_FILE)) {
	retval = write_file(filename, FALSE, 0, FALSE);

	/* Write succeeded. */
	if (retval == 1)
	    return retval;
    }

#ifndef NANO_SMALL
    if (ISSET(MARK_ISSET) && !exiting)
	ans = mallocstrcpy(NULL, "");
    else
#endif
	ans = mallocstrcpy(NULL, filename);

    while (TRUE) {
	const char *msg;
#ifndef NANO_SMALL
	const char *formatstr, *backupstr;

	if (ISSET(DOS_FILE))
	   formatstr = N_(" [DOS Format]");
	else if (ISSET(MAC_FILE))
	   formatstr = N_(" [Mac Format]");
	else
	   formatstr = "";

	if (ISSET(BACKUP_FILE))
	   backupstr = N_(" [Backup]");
	else
	   backupstr = "";

	/* Be nice to the translation folks. */
	if (ISSET(MARK_ISSET) && !exiting) {
	    if (append == 2)
		msg = N_("Prepend Selection to File");
	    else if (append == 1)
		msg = N_("Append Selection to File");
	    else
		msg = N_("Write Selection to File");
	} else
#endif /* !NANO_SMALL */
	if (append == 2)
	    msg = N_("File Name to Prepend to");
	else if (append == 1)
	    msg = N_("File Name to Append to");
	else
	    msg = N_("File Name to Write");

	/* If we're using restricted mode, the filename isn't blank,
	 * and we're at the "Write File" prompt, disable tab
	 * completion. */
	i = statusq(!ISSET(RESTRICTED) || filename[0] == '\0',
		writefile_list, ans,
#ifndef NANO_SMALL
		NULL, "%s%s%s", _(msg), formatstr, backupstr
#else
		"%s", _(msg)
#endif
		);

	if (i < 0) {
	    statusbar(_("Cancelled"));
	    retval = -1;
	    break;
	} else {
	    ans = mallocstrcpy(ans, answer);

#ifndef DISABLE_BROWSER
	    if (i == NANO_TOFILES_KEY) {
		char *tmp = do_browse_from(answer);

		currshortcut = writefile_list;

		if (tmp == NULL)
		    continue;
		free(answer);
		answer = tmp;

		/* We have a file now.  Get out of the statusbar prompt
		 * cleanly. */
		statusq_abort();
	    } else
#endif /* !DISABLE_BROWSER */
#ifndef NANO_SMALL
	    if (i == TOGGLE_DOS_KEY) {
		UNSET(MAC_FILE);
		TOGGLE(DOS_FILE);
		continue;
	    } else if (i == TOGGLE_MAC_KEY) {
		UNSET(DOS_FILE);
		TOGGLE(MAC_FILE);
		continue;
	    } else if (i == TOGGLE_BACKUP_KEY) {
		TOGGLE(BACKUP_FILE);
		continue;
	    } else
#endif /* !NANO_SMALL */
	    if (i == NANO_PREPEND_KEY) {
		append = (append == 2) ? 0 : 2;
		continue;
	    } else if (i == NANO_APPEND_KEY) {
		append = (append == 1) ? 0 : 1;
		continue;
	    }

#ifdef DEBUG
	    fprintf(stderr, "filename is %s\n", answer);
#endif

#ifdef NANO_EXTRA
	    if (exiting && !ISSET(TEMP_FILE) &&
		strcasecmp(answer, "zzy") == 0 && !did_cred) {
		do_credits();
		did_cred = TRUE;
		retval = -1;
		break;
	    }
#endif
	    if (append == 0 && strcmp(answer, filename) != 0) {
		struct stat st;

		if (!stat(answer, &st)) {
		    i = do_yesno(FALSE, _("File exists, OVERWRITE ? "));
		    if (i == 0 || i == -1)
			continue;
		/* If we're using restricted mode, we aren't allowed to
		 * change the name of a file once it has one because
		 * that would allow reading from or writing to files not
		 * specified on the command line.  In this case, don't
		 * bother showing the "Different Name" prompt. */
		} else if (!ISSET(RESTRICTED) && filename[0] != '\0'
#ifndef NANO_SMALL
			&& (exiting || !ISSET(MARK_ISSET))
#endif
			) {
		    i = do_yesno(FALSE, _("Save file under DIFFERENT NAME ? "));
		    if (i == 0 || i == -1)
			continue;
		}
	    }

#ifndef NANO_SMALL
	    /* Here's where we allow the selected text to be written to
	     * a separate file.  If we're using restricted mode, this is
	     * disabled since it allows reading from or writing to files
	     * not specified on the command line. */
	    if (!ISSET(RESTRICTED) && !exiting && ISSET(MARK_ISSET))
		retval = write_marked(answer, FALSE, append);
	    else
#endif /* !NANO_SMALL */
		retval = write_file(answer, FALSE, append, FALSE);

#ifdef ENABLE_MULTIBUFFER
	    /* If we're not about to exit, update the current entry in
	     * the open_files structure. */
	    if (!exiting)
		add_open_file(TRUE);
#endif

	    break;
	}
    } /* while (TRUE) */

    free(ans);
    return retval;
}

void do_writeout_void(void)
{
    do_writeout(FALSE);
    display_main_list();
}

/* Return a malloc()ed string containing the actual directory, used
 * to convert ~user and ~/ notation... */
char *real_dir_from_tilde(const char *buf)
{
    char *dirtmp = NULL;

    if (buf[0] == '~') {
	size_t i;
	const struct passwd *userdata;

	/* Figure how how much of the str we need to compare */
	for (i = 1; buf[i] != '/' && buf[i] != '\0'; i++)
	    ;

	/* Determine home directory using getpwuid() or getpwent(),
	   don't rely on $HOME */
	if (i == 1)
	    userdata = getpwuid(geteuid());
	else {
	    do {
		userdata = getpwent();
	    } while (userdata != NULL &&
			strncmp(userdata->pw_name, buf + 1, i - 1) != 0);
	}
	endpwent();

	if (userdata != NULL) {	/* User found */
	    dirtmp = charalloc(strlen(userdata->pw_dir) + strlen(buf + i) + 1);
	    sprintf(dirtmp, "%s%s", userdata->pw_dir, &buf[i]);
	}
    }

    if (dirtmp == NULL)
	dirtmp = mallocstrcpy(dirtmp, buf);

    return dirtmp;
}

#ifndef DISABLE_TABCOMP
/* Tack a slash onto the string we're completing if it's a directory.  We
 * assume there is room for one more character on the end of buf.  The
 * return value says whether buf is a directory. */
int append_slash_if_dir(char *buf, bool *lastwastab, int *place)
{
    char *dirptr = real_dir_from_tilde(buf);
    struct stat fileinfo;
    int ret = 0;

    assert(dirptr != buf);

    if (stat(dirptr, &fileinfo) != -1 && S_ISDIR(fileinfo.st_mode)) {
	strncat(buf, "/", 1);
	(*place)++;
	/* now we start over again with # of tabs so far */
	*lastwastab = FALSE;
	ret = 1;
    }

    free(dirptr);
    return ret;
}

/*
 * These functions (username_tab_completion(), cwd_tab_completion(), and
 * input_tab()) were taken from busybox 0.46 (cmdedit.c).  Here is the
 * notice from that file:
 *
 * Termios command line History and Editting, originally
 * intended for NetBSD sh (ash)
 * Copyright (c) 1999
 *      Main code:            Adam Rogoyski <rogoyski@cs.utexas.edu>
 *      Etc:                  Dave Cinege <dcinege@psychosis.com>
 *  Majorly adjusted/re-written for busybox:
 *                            Erik Andersen <andersee@debian.org>
 *
 * You may use this code as you wish, so long as the original author(s)
 * are attributed in any redistributions of the source code.
 * This code is 'as is' with no warranty.
 * This code may safely be consumed by a BSD or GPL license.
 */

char **username_tab_completion(char *buf, int *num_matches)
{
    char **matches = (char **)NULL;
    char *matchline = NULL;
    struct passwd *userdata;

    *num_matches = 0;
    matches = (char **)nmalloc(BUFSIZ * sizeof(char *));

    strcat(buf, "*");

    while ((userdata = getpwent()) != NULL) {

	if (check_wildcard_match(userdata->pw_name, &buf[1])) {

	    /* Cool, found a match.  Add it to the list
	     * This makes a lot more sense to me (Chris) this way...
	     */

#ifndef DISABLE_OPERATINGDIR
	    /* ...unless the match exists outside the operating
               directory, in which case just go to the next match */

	    if (operating_dir != NULL) {
		if (check_operating_dir(userdata->pw_dir, TRUE) != 0)
		    continue;
	    }
#endif

	    matchline = charalloc(strlen(userdata->pw_name) + 2);
	    sprintf(matchline, "~%s", userdata->pw_name);
	    matches[*num_matches] = matchline;
	    ++(*num_matches);

	    /* If there's no more room, bail out */
	    if (*num_matches == BUFSIZ)
		break;
	}
    }
    endpwent();

    return matches;
}

/* This was originally called exe_n_cwd_tab_completion, but we're not
   worried about executables, only filenames :> */

char **cwd_tab_completion(char *buf, int *num_matches)
{
    char *dirname, *dirtmp = NULL, *tmp = NULL, *tmp2 = NULL;
    char **matches = (char **)NULL;
    DIR *dir;
    struct dirent *next;

    matches = (char **)nmalloc(BUFSIZ * sizeof(char *));

    /* Stick a wildcard onto the buf, for later use */
    strcat(buf, "*");

    /* Okie, if there's a / in the buffer, strip out the directory part */
    if (buf[0] != '\0' && strstr(buf, "/") != NULL) {
	dirname = charalloc(strlen(buf) + 1);
	tmp = buf + strlen(buf);
	while (*tmp != '/' && tmp != buf)
	    tmp--;

	tmp++;

	strncpy(dirname, buf, tmp - buf + 1);
	dirname[tmp - buf] = '\0';

    } else {

	if ((dirname = getcwd(NULL, PATH_MAX + 1)) == NULL)
	    return matches;
	else
	    tmp = buf;
    }

#ifdef DEBUG
    fprintf(stderr, "\nDir = %s\n", dirname);
    fprintf(stderr, "\nbuf = %s\n", buf);
    fprintf(stderr, "\ntmp = %s\n", tmp);
#endif

    dirtmp = real_dir_from_tilde(dirname);
    free(dirname);
    dirname = dirtmp;

#ifdef DEBUG
    fprintf(stderr, "\nDir = %s\n", dirname);
    fprintf(stderr, "\nbuf = %s\n", buf);
    fprintf(stderr, "\ntmp = %s\n", tmp);
#endif


    dir = opendir(dirname);
    if (dir == NULL) {
	/* Don't print an error, just shut up and return */
	*num_matches = 0;
	beep();
	return matches;
    }
    while ((next = readdir(dir)) != NULL) {

#ifdef DEBUG
	fprintf(stderr, "Comparing \'%s\'\n", next->d_name);
#endif
	/* See if this matches */
	if (check_wildcard_match(next->d_name, tmp)) {

	    /* Cool, found a match.  Add it to the list
	     * This makes a lot more sense to me (Chris) this way...
	     */

#ifndef DISABLE_OPERATINGDIR
	    /* ...unless the match exists outside the operating
               directory, in which case just go to the next match; to
	       properly do operating directory checking, we have to add the
	       directory name to the beginning of the proposed match
	       before we check it */

	    if (operating_dir != NULL) {
		tmp2 = charalloc(strlen(dirname) + strlen(next->d_name) + 2);
		strcpy(tmp2, dirname);
		strcat(tmp2, "/");
		strcat(tmp2, next->d_name);
		if (check_operating_dir(tmp2, TRUE) != 0) {
		    free(tmp2);
		    continue;
		}
	        free(tmp2);
	    }
#endif

	    tmp2 = NULL;
	    tmp2 = charalloc(strlen(next->d_name) + 1);
	    strcpy(tmp2, next->d_name);
	    matches[*num_matches] = tmp2;
	    ++*num_matches;

	    /* If there's no more room, bail out */
	    if (*num_matches == BUFSIZ)
		break;
	}
    }
    closedir(dir);
    free(dirname);

    return matches;
}

/* This function now has an arg which refers to how much the statusbar
 * (place) should be advanced, i.e. the new cursor pos. */
char *input_tab(char *buf, int place, bool *lastwastab, int *newplace,
	bool *list)
{
    /* Do TAB completion */
    static int num_matches = 0, match_matches = 0;
    static char **matches = (char **)NULL;
    int pos = place, i = 0, col = 0, editline = 0;
    int longestname = 0, is_dir = 0;
    char *foo;

    *list = FALSE;

    if (*lastwastab == FALSE) {
	char *tmp, *copyto, *matchbuf;

	*lastwastab = TRUE;

	/* Make a local copy of the string -- up to the position of the
	   cursor */
	matchbuf = charalloc(strlen(buf) + 2);
	memset(matchbuf, '\0', strlen(buf) + 2);

	strncpy(matchbuf, buf, place);
	tmp = matchbuf;

	/* skip any leading white space */
	while (*tmp && isblank(*tmp))
	    ++tmp;

	/* Free up any memory already allocated */
	if (matches != NULL) {
	    for (i = i; i < num_matches; i++)
		free(matches[i]);
	    free(matches);
	    matches = (char **)NULL;
	    num_matches = 0;
	}

	/* If the word starts with `~' and there is no slash in the word, 
	 * then try completing this word as a username. */

	/* If the original string begins with a tilde, and the part
	   we're trying to tab-complete doesn't contain a slash, copy
	   the part we're tab-completing into buf, so tab completion
	   will result in buf's containing only the tab-completed
	   username. */
	if (buf[0] == '~' && strchr(tmp, '/') == NULL) {
	    buf = mallocstrcpy(buf, tmp);
	    matches = username_tab_completion(tmp, &num_matches);
	}
	/* If we're in the middle of the original line, copy the string
	   only up to the cursor position into buf, so tab completion
	   will result in buf's containing only the tab-completed
	   path/filename. */
	else if (strlen(buf) > strlen(tmp))
	    buf = mallocstrcpy(buf, tmp);

	/* Try to match everything in the current working directory that
	 * matches.  */
	if (matches == NULL)
	    matches = cwd_tab_completion(tmp, &num_matches);

	/* Don't leak memory */
	free(matchbuf);

#ifdef DEBUG
	fprintf(stderr, "%d matches found...\n", num_matches);
#endif
	/* Did we find exactly one match? */
	switch (num_matches) {
	case 0:
	    blank_edit();
	    wrefresh(edit);
	    break;
	case 1:

	    buf = charealloc(buf, strlen(buf) + strlen(matches[0]) + 1);

	    if (buf[0] != '\0' && strstr(buf, "/") != NULL) {
		for (tmp = buf + strlen(buf); *tmp != '/' && tmp != buf;
		     tmp--);
		tmp++;
	    } else
		tmp = buf;

	    if (strcmp(tmp, matches[0]) == 0)
		is_dir = append_slash_if_dir(buf, lastwastab, newplace);

	    if (is_dir != 0)
		break;

	    copyto = tmp;
	    for (pos = 0; *tmp == matches[0][pos] &&
		 pos <= strlen(matches[0]); pos++)
		tmp++;

	    /* write out the matched name */
	    strncpy(copyto, matches[0], strlen(matches[0]) + 1);
	    *newplace += strlen(matches[0]) - pos;

	    /* if an exact match is typed in and Tab is pressed,
	       *newplace will now be negative; in that case, make it
	       zero, so that the cursor will stay where it is instead of
	       moving backward */
	    if (*newplace < 0)
		*newplace = 0;

	    /* Is it a directory? */
	    append_slash_if_dir(buf, lastwastab, newplace);

	    break;
	default:
	    /* Check to see if all matches share a beginning, and, if so,
	       tack it onto buf and then beep */

	    if (buf[0] != '\0' && strstr(buf, "/") != NULL) {
		for (tmp = buf + strlen(buf); *tmp != '/' && tmp != buf;
		     tmp--);
		tmp++;
	    } else
		tmp = buf;

	    for (pos = 0; *tmp == matches[0][pos] && *tmp != '\0' &&
		 pos <= strlen(matches[0]); pos++)
		tmp++;

	    while (TRUE) {
		match_matches = 0;

		for (i = 0; i < num_matches; i++) {
		    if (matches[i][pos] == 0)
			break;
		    else if (matches[i][pos] == matches[0][pos])
			match_matches++;
		}
		if (match_matches == num_matches &&
		    (i == num_matches || matches[i] != 0)) {
		    /* All the matches have the same character at pos+1,
		       so paste it into buf... */
		    buf = charealloc(buf, strlen(buf) + 2);
		    strncat(buf, matches[0] + pos, 1);
		    *newplace += 1;
		    pos++;
		} else {
		    beep();
		    break;
		}
	    }
	}
    } else {
	/* Ok -- the last char was a TAB.  Since they
	 * just hit TAB again, print a list of all the
	 * available choices... */
	if (matches != NULL && num_matches > 1) {

	    /* Blank the edit window, and print the matches out there */
	    blank_edit();
	    wmove(edit, 0, 0);

	    editline = 0;

	    /* Figure out the length of the longest filename */
	    for (i = 0; i < num_matches; i++)
		if (strlen(matches[i]) > longestname)
		    longestname = strlen(matches[i]);

	    if (longestname > COLS - 1)
		longestname = COLS - 1;

	    foo = charalloc(longestname + 5);

	    /* Print the list of matches */
	    for (i = 0, col = 0; i < num_matches; i++) {

		/* make each filename shown be the same length as the longest
		   filename, with two spaces at the end */
		snprintf(foo, longestname + 1, matches[i]);
		while (strlen(foo) < longestname)
		    strcat(foo, " ");

		strcat(foo, "  ");

		/* Disable el cursor */
		curs_set(0);
		/* now, put the match on the screen */
		waddnstr(edit, foo, strlen(foo));
		col += strlen(foo);

		/* And if the next match isn't going to fit on the
		   line, move to the next one */
		if (col > COLS - longestname && i + 1 < num_matches) {
		    editline++;
		    wmove(edit, editline, 0);
		    if (editline == editwinrows - 1) {
			waddstr(edit, _("(more)"));
			break;
		    }
		    col = 0;
		}
	    }
	    free(foo);
	    wrefresh(edit);
	    *list = TRUE;
	} else
	    beep();
    }

    /* Only refresh the edit window if we don't have a list of filename
       matches on it */
    if (*list == FALSE)
	edit_refresh();
    curs_set(1);
    return buf;
}
#endif /* !DISABLE_TABCOMP */

/* Only print the last part of a path; isn't there a shell
 * command for this? */
const char *tail(const char *foo)
{
    const char *tmp = foo + strlen(foo);

    while (*tmp != '/' && tmp != foo)
	tmp--;

    if (*tmp == '/')
	tmp++;

    return tmp;
}

#ifndef DISABLE_BROWSER
/* Our sort routine for file listings -- sort directories before
 * files, and then alphabetically. */ 
int diralphasort(const void *va, const void *vb)
{
    struct stat fileinfo;
    const char *a = *(char *const *)va, *b = *(char *const *)vb;
    int aisdir = stat(a, &fileinfo) != -1 && S_ISDIR(fileinfo.st_mode);
    int bisdir = stat(b, &fileinfo) != -1 && S_ISDIR(fileinfo.st_mode);

    if (aisdir != 0 && bisdir == 0)
	return -1;
    if (aisdir == 0 && bisdir != 0)
	return 1;

    return strcasecmp(a, b);
}

/* Free our malloc()ed memory */
void free_charptrarray(char **array, size_t len)
{
    for (; len > 0; len--)
	free(array[len - 1]);
    free(array);
}

/* Strip one dir from the end of a string. */
void striponedir(char *foo)
{
    char *tmp;

    assert(foo != NULL);
    /* Don't strip the root dir */
    if (*foo == '\0' || strcmp(foo, "/") == 0)
	return;

    tmp = foo + strlen(foo) - 1;
    assert(tmp >= foo);
    if (*tmp == '/')
	*tmp = '\0';

    while (*tmp != '/' && tmp != foo)
	tmp--;

    if (tmp != foo)
	*tmp = '\0';
    else { /* SPK may need to make a 'default' path here */
        if (*tmp != '/')
	    *tmp = '.';
	*(tmp + 1) = '\0';
    }
}

int readable_dir(const char *path)
{
    DIR *dir = opendir(path);

    /* If dir is NULL, don't do closedir(), since that changes errno. */
    if (dir != NULL)
	closedir(dir);
    return dir != NULL;
}

/* Initialize the browser code, including the list of files in *path */
char **browser_init(const char *path, int *longest, int *numents)
{
    DIR *dir;
    struct dirent *next;
    char **filelist;
    int i = 0;
    size_t path_len;

    dir = opendir(path);
    if (dir == NULL)
	return NULL;

    *numents = 0;
    while ((next = readdir(dir)) != NULL) {
	if (strcmp(next->d_name, ".") == 0)
	   continue;
	(*numents)++;
	if (strlen(next->d_name) > *longest)
	    *longest = strlen(next->d_name);
    }
    rewinddir(dir);
    *longest += 10;

    filelist = (char **)nmalloc(*numents * sizeof (char *));

    if (strcmp(path, "/") == 0)
	path = "";
    path_len = strlen(path);

    while ((next = readdir(dir)) != NULL) {
	if (strcmp(next->d_name, ".") == 0)
	   continue;

	filelist[i] = charalloc(strlen(next->d_name) + path_len + 2);
	sprintf(filelist[i], "%s/%s", path, next->d_name);
	i++;
    }
    closedir(dir);

    if (*longest > COLS - 1)
	*longest = COLS - 1;

    return filelist;
}

/* Our browser function.  inpath is the path to start browsing from */
char *do_browser(const char *inpath)
{
    struct stat st;
    char *foo, *retval = NULL;
    static char *path = NULL;
    int numents = 0, i = 0, j = 0, longest = 0, abort = 0, col = 0;
    int selected = 0, editline = 0, width = 0, filecols = 0, lineno = 0;
    int kbinput = ERR;
    bool meta_key, func_key;
    char **filelist = (char **)NULL;
#ifndef DISABLE_MOUSE
    MEVENT mevent;
#endif

    assert(inpath != NULL);

    /* If path isn't the same as inpath, we are being passed a new
	dir as an arg.  We free it here so it will be copied from 
	inpath below */
    if (path != NULL && strcmp(path, inpath) != 0) {
	free(path);
	path = NULL;
    }

    /* if path doesn't exist, make it so */
    if (path == NULL)
	path = mallocstrcpy(NULL, inpath);

    filelist = browser_init(path, &longest, &numents);
    foo = charalloc(longest + 8);

    /* Sort the list by directory first, then alphabetically */
    qsort(filelist, numents, sizeof(char *), diralphasort);

    titlebar(path);
    bottombars(browser_list);
    curs_set(0);
    wmove(edit, 0, 0);
    i = 0;
    width = 0;
    filecols = 0;

    /* Loop invariant: Microsoft sucks. */
    do {
	char *new_path;
	    /* Used by the Go To Directory prompt. */

	check_statusblank();

#if !defined(DISABLE_HELP) || !defined(DISABLE_MOUSE)
	currshortcut = browser_list;
#endif

 	editline = 0;
	col = 0;
	    
	/* Compute line number we're on now, so we don't divide by zero later */
	lineno = selected;
	if (width != 0)
	    lineno /= width;

	switch (kbinput) {

#ifndef DISABLE_MOUSE
	case KEY_MOUSE:
	    if (getmouse(&mevent) == ERR)
		return retval;
 
	    /* If they clicked in the edit window, they probably clicked
		on a file */
	    if (wenclose(edit, mevent.y, mevent.x)) { 
		int selectedbackup = selected;

		mevent.y -= 2;

		/* Longest is the width of each column.  There are two
		 * spaces between each column. */
		selected = (lineno / editwinrows) * editwinrows * width
			+ mevent.y * width + mevent.x / (longest + 2);

		/* If they clicked beyond the end of a row, select the
		 * end of that row. */
		if (mevent.x > width * (longest + 2))
		    selected--;

		/* If we're off the screen, reset to the last item.
		   If we clicked where we did last time, select this name! */
		if (selected > numents - 1)
		    selected = numents - 1;
		else if (selectedbackup == selected)
		    /* Unget the 'select' key */
		    unget_kbinput('s', FALSE, FALSE);
	    } else {
		/* Must be clicking a shortcut */
		int mouse_x, mouse_y;
		get_mouseinput(&mouse_x, &mouse_y, TRUE);
	    }

            break;
#endif
	case NANO_PREVLINE_KEY:
	    if (selected - width >= 0)
		selected -= width;
	    break;
	case NANO_BACK_KEY:
	    if (selected > 0)
		selected--;
	    break;
	case NANO_NEXTLINE_KEY:
	    if (selected + width <= numents - 1)
		selected += width;
	    break;
	case NANO_FORWARD_KEY:
	    if (selected < numents - 1)
		selected++;
	    break;
	case NANO_PREVPAGE_KEY:
	case NANO_PREVPAGE_FKEY:
	case '-': /* Pico compatibility */
	    if (selected >= (editwinrows + lineno % editwinrows) * width)
		selected -= (editwinrows + lineno % editwinrows) * width;
	    else
		selected = 0;
	    break;
	case NANO_NEXTPAGE_KEY:
	case NANO_NEXTPAGE_FKEY:
	case ' ': /* Pico compatibility */
	    selected += (editwinrows - lineno % editwinrows) * width;
	    if (selected >= numents)
		selected = numents - 1;
	    break;
	case NANO_HELP_KEY:
	case NANO_HELP_FKEY:
	case '?': /* Pico compatibility */
#ifndef DISABLE_HELP
	    do_help();
	    curs_set(0);
#else
	    nano_disabled_msg();
#endif
	    break;
	case NANO_ENTER_KEY:
	case 'S': /* Pico compatibility */
	case 's':
	    /* You can't cd up from / */
	    if (strcmp(filelist[selected], "/..") == 0 &&
		strcmp(path, "/") == 0) {
		statusbar(_("Can't move up a directory"));
		beep();
		break;
	    }

#ifndef DISABLE_OPERATINGDIR
	    /* Note: the selected file can be outside the operating
	     * directory if it is .. or if it is a symlink to 
	     * directory outside the operating directory. */
	    if (check_operating_dir(filelist[selected], FALSE) != 0) {
		statusbar(_("Can't go outside of %s in restricted mode"),
			operating_dir);
		beep();
		break;
	    }
#endif

	    if (stat(filelist[selected], &st) == -1) {
		statusbar(_("Can't open \"%s\": %s"), filelist[selected],
			strerror(errno));
		beep();
		break;
	    }

	    if (!S_ISDIR(st.st_mode)) {
		retval = mallocstrcpy(retval, filelist[selected]);
		abort = 1;
		break;
	    }

	    new_path = mallocstrcpy(NULL, filelist[selected]);

	    if (strcmp("..", tail(new_path)) == 0) {
		/* They want to go up a level, so strip off .. and the
		   current dir */
		striponedir(new_path);
		/* SPK for '.' path, get the current path via getcwd */
		if (strcmp(new_path, ".") == 0) {
		    free(new_path);
		    new_path = getcwd(NULL, PATH_MAX + 1);
		}
		striponedir(new_path);
	    }

	    if (!readable_dir(new_path)) {
		/* We can't open this dir for some reason.  Complain */
		statusbar(_("Can't open \"%s\": %s"), new_path,
			strerror(errno));
		free(new_path);
		break;
	    }

	    free_charptrarray(filelist, numents);
	    free(foo);
	    free(path);
	    path = new_path;
	    return do_browser(path);

	/* Go to a specific directory */
	case NANO_GOTOLINE_KEY:
	case NANO_GOTOLINE_FKEY:
	case 'G': /* Pico compatibility */
	case 'g':
	    curs_set(1);
	    j = statusq(FALSE, gotodir_list, "",
#ifndef NANO_SMALL
		NULL,
#endif
		_("Go To Directory"));
	    bottombars(browser_list);
	    curs_set(0);

	    if (j < 0) {
		statusbar(_("Cancelled"));
		break;
	    }

	    new_path = real_dir_from_tilde(answer);

	    if (new_path[0] != '/') {
		new_path = charealloc(new_path, strlen(path) + strlen(answer) + 2);
		sprintf(new_path, "%s/%s", path, answer);
	    }

#ifndef DISABLE_OPERATINGDIR
	    if (check_operating_dir(new_path, FALSE) != 0) {
		statusbar(_("Can't go outside of %s in restricted mode"), operating_dir);
		free(new_path);
		break;
	    }
#endif

	    if (!readable_dir(new_path)) {
		/* We can't open this dir for some reason.  Complain */
		statusbar(_("Can't open \"%s\": %s"), answer, strerror(errno));
		free(new_path);
		break;
	    }

	    /* Start over again with the new path value */
	    free_charptrarray(filelist, numents);
	    free(foo);
	    free(path);
	    path = new_path;
	    return do_browser(path);

	/* Stuff we want to abort the browser */
	case NANO_CANCEL_KEY:
	case NANO_EXIT_KEY:
	case NANO_EXIT_FKEY:
	case 'E': /* Pico compatibility */
	case 'e':
	    abort = 1;
	    break;
	}
	if (abort)
	    break;

	blank_edit();

	if (width != 0)
	    i = width * editwinrows * ((selected / width) / editwinrows);
	else
	    i = 0;

	wmove(edit, 0, 0);
	for (j = i; j < numents && editline <= editwinrows - 1; j++) {
	    filecols++;

	    strncpy(foo, tail(filelist[j]), strlen(tail(filelist[j])) + 1);
	    while (strlen(foo) < longest)
		strcat(foo, " ");
	    col += strlen(foo);

	    /* Put file info in the string also */
	    /* We use lstat here to detect links; then, if we find a
		symlink, we examine it via stat() to see if it is a
		directory or just a file symlink */
	    lstat(filelist[j], &st);
	    if (S_ISDIR(st.st_mode))
		strcpy(foo + longest - 5, "(dir)");
	    else {
		if (S_ISLNK(st.st_mode)) {
		     /* Aha!  It's a symlink!  Now, is it a dir?  If so,
			mark it as such */
		    stat(filelist[j], &st);
		    if (S_ISDIR(st.st_mode))
			strcpy(foo + longest - 5, "(dir)");
		    else
			strcpy(foo + longest - 2, "--");
		} else if (st.st_size < (1 << 10)) /* less than 1 K */
		    sprintf(foo + longest - 7, "%4d  B", 
			(int) st.st_size);
		else if (st.st_size >= (1 << 30)) /* at least 1 gig */
		    sprintf(foo + longest - 7, "%4d GB", 
			(int) st.st_size >> 30);
		else if (st.st_size >= (1 << 20)) /* at least 1 meg */
		    sprintf(foo + longest - 7, "%4d MB", 
			(int) st.st_size >>     20);
		else /* It's more than 1 k and less than a meg */
		    sprintf(foo + longest - 7, "%4d KB", 
			(int) st.st_size >> 10);
	    }

	    /* Highlight the currently selected file/dir */
	    if (j == selected)
		wattron(edit, A_REVERSE);
	    waddstr(edit, foo);
	    if (j == selected)
		wattroff(edit, A_REVERSE);

	    /* And add some space between the cols */
	    waddstr(edit, "  ");
	    col += 2;

	    /* And if the next entry isn't going to fit on the
		line, move to the next one */
	    if (col > COLS - longest) {
		editline++;
		wmove(edit, editline, 0);
		col = 0;
		if (width == 0)
		    width = filecols;
	    }
	}
	wrefresh(edit);
    } while ((kbinput = get_kbinput(edit, &meta_key, &func_key)) !=
	NANO_EXIT_KEY && kbinput != NANO_EXIT_FKEY);
    curs_set(1);
    blank_edit();
    titlebar(NULL);
    edit_refresh();

    /* cleanup */
    free_charptrarray(filelist, numents);
    free(foo);
    return retval;
}

/* Browser front end, checks to see if inpath has a dir in it and, if so,
 starts do_browser from there, else from the current dir */
char *do_browse_from(const char *inpath)
{
    struct stat st;
    char *bob;
	/* The result of do_browser; the selected file name. */
    char *path;
	/* inpath, tilde expanded. */

    assert(inpath != NULL);

    path = real_dir_from_tilde(inpath);

    /*
     * Perhaps path is a directory.  If so, we will pass that to
     * do_browser.  Otherwise, perhaps path is a directory / a file.  So
     * we try stripping off the last path element.  If it still isn't a
     * directory, just use the current directory. */

    if (stat(path, &st) == -1 || !S_ISDIR(st.st_mode)) {
	striponedir(path);
	if (stat(path, &st) == -1 || !S_ISDIR(st.st_mode)) {
	    free(path);
	    path = getcwd(NULL, PATH_MAX + 1);
	}
    }

#ifndef DISABLE_OPERATINGDIR
    /* If the resulting path isn't in the operating directory, use that. */
    if (check_operating_dir(path, FALSE) != 0)
	path = mallocstrcpy(path, operating_dir);
#endif

    if (!readable_dir(path)) {
	beep();
	bob = NULL;
    } else
	bob = do_browser(path);
    free(path);
    return bob;
}
#endif /* !DISABLE_BROWSER */

#if !defined(NANO_SMALL) && defined(ENABLE_NANORC)
/* Return $HOME/.nano_history, or NULL if we can't find the homedir.
 * The string is dynamically allocated, and should be freed. */
char *histfilename(void)
{
    char *nanohist = NULL;

    if (homedir != NULL) {
	size_t homelen = strlen(homedir);

	nanohist = charalloc(homelen + 15);
	strcpy(nanohist, homedir);
	strcpy(nanohist + homelen, "/.nano_history");
    }
    return nanohist;
}

void load_history(void)
{
    char *nanohist = histfilename();

    /* assume do_rcfile() has reported missing home dir */
    if (nanohist != NULL) {
	FILE *hist = fopen(nanohist, "r");

	if (hist == NULL) {
	    if (errno != ENOENT) {
		/* Don't save history when we quit. */
		UNSET(HISTORYLOG);
		rcfile_error(N_("Error reading %s: %s"), nanohist, strerror(errno));
		fprintf(stderr, _("\nPress Return to continue starting nano\n"));
		while (getchar() != '\n')
		    ;
	    }
	} else {
	    historyheadtype *history = &search_history;
	    char *line = NULL;
	    size_t buflen = 0;
	    ssize_t read;

	    while ((read = getline(&line, &buflen, hist)) >= 0) {
		if (read > 0 && line[read - 1] == '\n') {
		    read--;
		    line[read] = '\0';
		}
		if (read > 0) {
		    unsunder(line, read);
		    update_history(history, line);
		} else
		    history = &replace_history;
	    }
	    fclose(hist);
	    free(line);
	    UNSET(HISTORY_CHANGED);
	}
	free(nanohist);
    }
}

bool writehist(FILE *hist, historyheadtype *histhead)
{
    historytype *h;

    /* write oldest first */
    for (h = histhead->tail; h->prev != NULL; h = h->prev) {
	size_t len = strlen(h->data);

	sunder(h->data);
	if (fwrite(h->data, sizeof(char), len, hist) < len ||
		putc('\n', hist) == EOF)
	    return FALSE;
    }
    return TRUE;
}

/* save histories to ~/.nano_history */
void save_history(void)
{
    char *nanohist;

    /* don't save unchanged or empty histories */
    if ((search_history.count == 0 && replace_history.count == 0) ||
	!ISSET(HISTORY_CHANGED) || ISSET(VIEW_MODE))
	return;

    nanohist = histfilename();

    if (nanohist != NULL) {
	FILE *hist = fopen(nanohist, "wb");

	if (hist == NULL)
	    rcfile_error(N_("Error writing %s: %s"), nanohist, strerror(errno));
	else {
	    /* set rw only by owner for security ?? */
	    chmod(nanohist, S_IRUSR | S_IWUSR);

	    if (!writehist(hist, &search_history) ||
		    putc('\n', hist) == EOF ||
		    !writehist(hist, &replace_history))
		rcfile_error(N_("Error writing %s: %s"), nanohist, strerror(errno));
	    fclose(hist);
	}
	free(nanohist);
    }
}
#endif /* !NANO_SMALL && ENABLE_NANORC */