/****************************************************************************
 * Copyright (c) 1998 Free Software Foundation, Inc.                        *
 *                                                                          *
 * Permission is hereby granted, free of charge, to any person obtaining a  *
 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
 * without limitation the rights to use, copy, modify, merge, publish,      *
 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
 *                                                                          *
 * The above copyright notice and this permission notice shall be included  *
 * in all copies or substantial portions of the Software.                   *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
 ****************************************************************************/



/*
 *	write_entry.c -- write a terminfo structure onto the file system
 */

#include <curses.priv.h>

#include <sys/stat.h>

#include <tic.h>
#include <term_entry.h>

#ifndef S_ISDIR
#define S_ISDIR(mode) ((mode & S_IFMT) == S_IFDIR)
#endif

#if 0
#define TRACE_OUT(p) DEBUG(2, p)
#else
#define TRACE_OUT(p) /*nothing*/
#endif

MODULE_ID("$Id: write_entry.c,v 1.47 1999/07/10 20:29:22 tom Exp $")

static int total_written;

static int write_object(FILE *, TERMTYPE *);

static void write_file(char *filename, TERMTYPE *tp)
{
	FILE *fp = (_nc_access(filename, W_OK) == 0) ? fopen(filename, "wb") : 0;
	if (fp == 0) {
		perror(filename);
		_nc_syserr_abort("can't open %s/%s", _nc_tic_dir(0), filename);
	}
	DEBUG(1, ("Created %s", filename));

	if (write_object(fp, tp) == ERR) {
		_nc_syserr_abort("error writing %s/%s", _nc_tic_dir(0), filename);
	}
	fclose(fp);
}

/*
 *	make_directory(char *path)
 *
 *	Make a directory if it doesn't exist.
 */
static int make_directory(const char *path)
{
int	rc;
struct	stat	statbuf;
char	fullpath[PATH_MAX];
const char *destination = _nc_tic_dir(0);

	if (path == destination || *path == '/') {
		if (strlen(path) + 1 > sizeof(fullpath))
			return(-1);
		(void)strcpy(fullpath, path);
	} else {
		if (strlen(destination) + strlen(path) + 2 > sizeof(fullpath))
			return(-1);
		(void)sprintf(fullpath, "%s/%s", destination, path);
	}

	if ((rc = stat(path, &statbuf)) < 0) {
		rc = mkdir(path, 0777);
	} else {
		if (_nc_access(path, R_OK|W_OK|X_OK) < 0) {
			rc = -1;	/* permission denied */
		} else if (!(S_ISDIR(statbuf.st_mode))) {
			rc = -1;	/* not a directory */
		}
	}
	return rc;
}

void  _nc_set_writedir(char *dir)
/* set the write directory for compiled entries */
{
    const char *destination;
    char actual[PATH_MAX];

    if (dir != 0)
	(void) _nc_tic_dir(dir);
    else if (getenv("TERMINFO") != NULL)
	(void) _nc_tic_dir(getenv("TERMINFO"));

    destination = _nc_tic_dir(0);
    if (make_directory(destination) < 0)
    {
	char	*home = _nc_home_terminfo();

	if (home != 0) {
	    destination = home;
	    if (make_directory(destination) < 0)
		_nc_err_abort("%s: permission denied (errno %d)",
			destination, errno);
	}
    }

    /*
     * Note: because of this code, this logic should be exercised
     * *once only* per run.
     */
    if (chdir(_nc_tic_dir(destination)) < 0
     || getcwd(actual, sizeof(actual)) == 0)
	_nc_err_abort("%s: not a directory", destination);
    _nc_keep_tic_dir(strdup(actual));
}

/*
 *	check_writeable(char code)
 *
 *	Miscellaneous initialisations
 *
 *	Check for access rights to destination directories
 *	Create any directories which don't exist.
 *	Note: there's no reason to return the result of make_directory(), since
 *	this function is called only in instances where that has to succeed.
 *
 */

static void check_writeable(int code)
{
static const char dirnames[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
static bool verified[sizeof(dirnames)];

char		dir[2];
char		*s;

	if (code == 0 || (s = strchr(dirnames, code)) == 0)
	    _nc_err_abort("Illegal terminfo subdirectory \"%c\"", code);

	if (verified[s-dirnames])
	    return;

	dir[0] = code;
	dir[1] = '\0';
	if (make_directory(dir) < 0) {
		_nc_err_abort("%s/%s: permission denied", _nc_tic_dir(0), dir);
	}

	verified[s-dirnames] = TRUE;
}

/*
 *	_nc_write_entry()
 *
 *	Save the compiled version of a description in the filesystem.
 *
 *	make a copy of the name-list
 *	break it up into first-name and all-but-last-name
 *	creat(first-name)
 *	write object information to first-name
 *	close(first-name)
 *      for each name in all-but-last-name
 *	    link to first-name
 *
 *	Using 'time()' to obtain a reference for file timestamps is unreliable,
 *	e.g., with NFS, because the filesystem may have a different time
 *	reference.  We check for pre-existence of links by latching the first
 *	timestamp from a file that we create.
 *
 *	The _nc_warning() calls will report a correct line number only if
 *	_nc_curr_line is properly set before the write_entry() call.
 */

void _nc_write_entry(TERMTYPE *const tp)
{
struct stat	statbuf;
char		name_list[MAX_TERMINFO_LENGTH];
char		*first_name, *other_names;
char		*ptr;
char		filename[PATH_MAX];
char		linkname[PATH_MAX];
#if USE_SYMLINKS
char		symlinkname[PATH_MAX];
#endif /* USE_SYMLINKS */
static int	call_count;
static time_t	start_time;		/* time at start of writes */

	if (call_count++ == 0) {
		start_time = 0;
	}

	(void) strcpy(name_list, tp->term_names);
	DEBUG(7, ("Name list = '%s'", name_list));

	first_name = name_list;

	ptr = &name_list[strlen(name_list) - 1];
	other_names = ptr + 1;

	while (ptr > name_list  &&  *ptr != '|')
		ptr--;

	if (ptr != name_list) {
		*ptr = '\0';

		for (ptr = name_list; *ptr != '\0' && *ptr != '|'; ptr++)
			continue;

		if (*ptr == '\0')
			other_names = ptr;
		else {
			*ptr = '\0';
			other_names = ptr + 1;
		}
	}

	DEBUG(7, ("First name = '%s'", first_name));
	DEBUG(7, ("Other names = '%s'", other_names));

	_nc_set_type(first_name);

	if (strlen(first_name) > sizeof(filename)-3)
		_nc_warning("terminal name too long.");

	sprintf(filename, "%c/%s", first_name[0], first_name);

	/*
	 * Has this primary name been written since the first call to
	 * write_entry()?  If so, the newer write will step on the older,
	 * so warn the user.
	 */
	if (start_time > 0 &&
	    stat(filename, &statbuf) >= 0
	    && statbuf.st_mtime >= start_time)
	{
		_nc_warning("name multiply defined.");
	}

	check_writeable(first_name[0]);
	write_file(filename, tp);

	if (start_time == 0) {
		if (stat(filename, &statbuf) < 0
		 || (start_time = statbuf.st_mtime) == 0) {
			_nc_syserr_abort("error obtaining time from %s/%s",
				_nc_tic_dir(0), filename);
		}
	}
	while (*other_names != '\0') {
		ptr = other_names++;
		while (*other_names != '|'  &&	*other_names != '\0')
			other_names++;

		if (*other_names != '\0')
			*(other_names++) = '\0';

		if (strlen(ptr) > sizeof(linkname)-3) {
			_nc_warning("terminal alias %s too long.", ptr);
			continue;
		}
		if (strchr(ptr, '/') != 0) {
			_nc_warning("cannot link alias %s.", ptr);
			continue;
		}

		check_writeable(ptr[0]);
		sprintf(linkname, "%c/%s", ptr[0], ptr);

		if (strcmp(filename, linkname) == 0) {
			_nc_warning("self-synonym ignored");
		}
		else if (stat(linkname, &statbuf) >= 0	&&
						statbuf.st_mtime < start_time)
		{
			_nc_warning("alias %s multiply defined.", ptr);
		}
		else if (_nc_access(linkname, W_OK) == 0)
#if HAVE_LINK
		{
			int code;
#if USE_SYMLINKS
			strcpy(symlinkname, "../");
			strncat(symlinkname, filename, sizeof(symlinkname) - 4);
			symlinkname[sizeof(symlinkname) - 1] = '\0';
#endif /* USE_SYMLINKS */
#if HAVE_REMOVE
			code = remove(linkname);
#else
			code = unlink(linkname);
#endif
			if (code != 0 && errno == ENOENT)
				code = 0;
#if USE_SYMLINKS
			if (symlink(symlinkname, linkname) < 0)
#else
			if (link(filename, linkname) < 0)
#endif /* USE_SYMLINKS */
			{
			    /*
			     * If there wasn't anything there, and we cannot
			     * link to the target because it is the same as the
			     * target, then the source must be on a filesystem
			     * that uses caseless filenames, such as Win32, etc.
			     */
			    if (code == 0 && errno == EEXIST)
				_nc_warning("can't link %s to %s", filename, linkname);
			    else if (code == 0 && errno == EPERM)
				write_file(linkname, tp);
			    else
				_nc_syserr_abort("can't link %s to %s", filename, linkname);
			}
			else
			{
			    DEBUG(1, ("Linked %s", linkname));
			}
		}
#else /* just make copies */
		write_file(linkname, tp);
#endif /* HAVE_LINK */
	}
}

#undef LITTLE_ENDIAN	/* BSD/OS defines this as a feature macro */
#define HI(x)			((x) / 256)
#define LO(x)			((x) % 256)
#define LITTLE_ENDIAN(p, x)	(p)[0] = LO(x), (p)[1] = HI(x)

#define WRITE_STRING(str) (fwrite(str, sizeof(char), strlen(str) + 1, fp) == strlen(str) + 1)

static int compute_offsets(char **Strings, int strmax, short *offsets)
{
    size_t nextfree = 0;
    int i;

    for (i = 0; i < strmax; i++) {
	if (Strings[i] == ABSENT_STRING) {
	    offsets[i] = -1;
	} else if (Strings[i] == CANCELLED_STRING) {
	    offsets[i] = -2;
	} else {
	    offsets[i] = nextfree;
	    nextfree += strlen(Strings[i]) + 1;
	    TRACE_OUT(("put Strings[%d]=%s(%d)", i, _nc_visbuf(Strings[i]), nextfree));
	}
    }
    return nextfree;
}

static void convert_shorts(unsigned char *buf, short *Numbers, int count)
{
    int i;
    for (i = 0; i < count; i++) {
	if (Numbers[i] == -1) {		/* HI/LO won't work */
	    buf[2*i] = buf[2*i + 1] = 0377;
	} else if (Numbers[i] == -2) {	/* HI/LO won't work */
	    buf[2*i] = 0376;
	    buf[2*i + 1] = 0377;
	} else {
	    LITTLE_ENDIAN(buf + 2*i, Numbers[i]);
	    TRACE_OUT(("put Numbers[%d]=%d", i, Numbers[i]));
	}
    }
}

#define even_boundary(value) \
	    ((value) % 2 != 0 && fwrite(&zero, sizeof(char), 1, fp) != 1)

static int write_object(FILE *fp, TERMTYPE *tp)
{
char		*namelist;
size_t		namelen, boolmax, nummax, strmax;
char		zero = '\0';
size_t		i;
short		nextfree;
short		offsets[MAX_ENTRY_SIZE/2];
unsigned char	buf[MAX_ENTRY_SIZE];

	namelist = tp->term_names;
	namelen = strlen(namelist) + 1;

	/*
	 * BOOLWRITE, etc., are less than BOOLCOUNT because we store some
	 * values internally.
	 */
	boolmax = 0;
	for (i = 0; i < BOOLWRITE; i++) {
	    if (tp->Booleans[i])
		boolmax = i+1;
	}

	nummax = 0;
	for (i = 0; i < NUMWRITE; i++) {
	    if (tp->Numbers[i] != ABSENT_NUMERIC)
		nummax = i+1;
	}

	strmax = 0;
	for (i = 0; i < STRWRITE; i++) {
	    if (tp->Strings[i] != ABSENT_STRING)
		strmax = i+1;
	}

	nextfree = compute_offsets(tp->Strings, strmax, offsets);

	/* fill in the header */
	LITTLE_ENDIAN(buf,    MAGIC);
	LITTLE_ENDIAN(buf+2,  min(namelen, MAX_NAME_SIZE + 1));
	LITTLE_ENDIAN(buf+4,  boolmax);
	LITTLE_ENDIAN(buf+6,  nummax);
	LITTLE_ENDIAN(buf+8,  strmax);
	LITTLE_ENDIAN(buf+10, nextfree);

	/* write out the header */
	TRACE_OUT(("Header of %s @%ld", namelist, ftell(fp)));
	if (fwrite(buf, 12, 1, fp) != 1
	    ||  fwrite(namelist, sizeof(char), namelen, fp) != namelen
	    ||  fwrite(tp->Booleans, sizeof(char), boolmax, fp) != boolmax)
	    return(ERR);

	if (even_boundary(namelen+boolmax))
	    return(ERR);

	TRACE_OUT(("Numerics begin at %04lx", ftell(fp)));

	/* the numerics */
	convert_shorts(buf, tp->Numbers, nummax);
	if (fwrite(buf, 2, nummax, fp) != nummax)
	    return(ERR);

	TRACE_OUT(("String offsets begin at %04lx", ftell(fp)));

	/* the string offsets */
	convert_shorts(buf, offsets, strmax);
	if (fwrite(buf, 2, strmax, fp) != strmax)
	    return(ERR);

	TRACE_OUT(("String table begins at %04lx", ftell(fp)));

	/* the strings */
	for (i = 0; i < strmax; i++)
	    if (VALID_STRING(tp->Strings[i]))
		if (!WRITE_STRING(tp->Strings[i]))
		    return(ERR);

#if NCURSES_XNAMES
	if (NUM_EXT_NAMES(tp)) {
	    unsigned extcnt = NUM_EXT_NAMES(tp);

	    if (even_boundary(nextfree))
		return(ERR);

	    nextfree = compute_offsets(tp->Strings + STRCOUNT, tp->ext_Strings, offsets);
	    TRACE_OUT(("after extended string capabilities, nextfree=%d", nextfree));
	    nextfree += compute_offsets(tp->ext_Names, extcnt, offsets + tp->ext_Strings);
	    TRACE_OUT(("after extended capnames, nextfree=%d", nextfree));
	    strmax = tp->ext_Strings + extcnt;

	    /*
	     * Write the extended header
	     */
	    LITTLE_ENDIAN(buf+0, tp->ext_Booleans);
	    LITTLE_ENDIAN(buf+2, tp->ext_Numbers);
	    LITTLE_ENDIAN(buf+4, tp->ext_Strings);
	    LITTLE_ENDIAN(buf+6, strmax);
	    LITTLE_ENDIAN(buf+8, nextfree);
	    TRACE_OUT(("WRITE extended-header @%ld", ftell(fp)));
	    if (fwrite(buf, 10, 1, fp) != 1)
		return(ERR);

	    TRACE_OUT(("WRITE %d booleans @%ld", tp->ext_Booleans, ftell(fp)));
	    if (tp->ext_Booleans
	     && fwrite(tp->Booleans + BOOLCOUNT, sizeof(char), tp->ext_Booleans, fp) != tp->ext_Booleans)
		return(ERR);

	    if (even_boundary(tp->ext_Booleans))
		return(ERR);

	    TRACE_OUT(("WRITE %d numbers @%ld", tp->ext_Numbers, ftell(fp)));
	    if (tp->ext_Numbers) {
		convert_shorts(buf, tp->Numbers + NUMCOUNT, tp->ext_Numbers);
		if (fwrite(buf, 2, tp->ext_Numbers, fp) != tp->ext_Numbers)
		    return(ERR);
	    }

	    /*
	     * Convert the offsets for the ext_Strings and ext_Names tables,
	     * in that order.
	     */
	    convert_shorts(buf, offsets, strmax);
	    TRACE_OUT(("WRITE offsets @%ld", ftell(fp)));
	    if (fwrite(buf, 2, strmax, fp) != strmax)
		return(ERR);

	    /*
	     * Write the string table after the offset tables so we do not
	     * have to do anything about alignment.
	     */
	    for (i = 0; i < tp->ext_Strings; i++) {
		if (VALID_STRING(tp->Strings[i+STRCOUNT])) {
		    TRACE_OUT(("WRITE ext_Strings[%d]=%s", i, _nc_visbuf(tp->Strings[i+STRCOUNT])));
		    if (!WRITE_STRING(tp->Strings[i+STRCOUNT]))
			return(ERR);
		}
	    }

	    /*
	     * Write the extended names
	     */
	    for (i = 0; i < extcnt; i++) {
		TRACE_OUT(("WRITE ext_Names[%d]=%s", i, tp->ext_Names[i]));
		if (!WRITE_STRING(tp->ext_Names[i]))
		    return(ERR);
	    }

	}
#endif /* NCURSES_XNAMES */

	total_written++;
	return(OK);
}

/*
 * Returns the total number of entries written by this process
 */
int _nc_tic_written(void)
{
	return total_written;
}
