/* Utilities for VFS modules.

   Copyright (C) 1988, 1992 Free Software Foundation
   Copyright (C) 1995, 1996 Miguel de Icaza
   
   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License
   as published by the Free Software Foundation; either version 2 of
   the License, 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 Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include <config.h>
#include <ctype.h>

#include "utilvfs.h"
#include "vfs.h"

/* Extract the hostname and username from the path */
/* path is in the form: [user@]hostname:port/remote-dir, e.g.:
 *
 * ftp://sunsite.unc.edu/pub/linux
 * ftp://miguel@sphinx.nuclecu.unam.mx/c/nc
 * ftp://tsx-11.mit.edu:8192/
 * ftp://joe@foo.edu:11321/private
 * ftp://joe:password@foo.se
 *
 * Returns g_malloc()ed host, user and pass they are present.
 * If the user is empty, e.g. ftp://@roxanne/private, and URL_ALLOW_ANON
 * is not set, then the current login name is supplied.
 *
 * Return value is a g_malloc()ed string with the pathname relative to the
 * host.
 */

#ifdef USE_NETCODE
char *
vfs_split_url (const char *path, char **host, char **user, int *port,
	       char **pass, int default_port, int flags)
{
    struct passwd *passwd_info;
    char *dir, *colon, *inner_colon, *at, *rest;
    char *retval;
    char *pcopy = g_strdup (path);
    char *pend = pcopy + strlen (pcopy);

    if (pass)
	*pass = NULL;
    *port = default_port;
    *user = NULL;
    retval = NULL;

    dir = pcopy;
    if (!(flags & URL_NOSLASH)) {
	/* locate path component */
	while (*dir != PATH_SEP && *dir)
	    dir++;
	if (*dir) {
	    retval = g_strdup (dir);
	    *dir = 0;
	} else
	    retval = g_strdup (PATH_SEP_STR);
    }

    /* search for any possible user */
    at = strchr (pcopy, '@');

    /* We have a username */
    if (at) {
	*at = 0;
	inner_colon = strchr (pcopy, ':');
	if (inner_colon) {
	    *inner_colon = 0;
	    inner_colon++;
	    if (pass)
		*pass = g_strdup (inner_colon);
	}
	if (*pcopy != 0)
	    *user = g_strdup (pcopy);

	if (pend == at + 1)
	    rest = at;
	else
	    rest = at + 1;
    } else
	rest = pcopy;

    if (!*user && !(flags & URL_ALLOW_ANON)) {
	passwd_info = getpwuid (geteuid ());
	if (passwd_info && passwd_info->pw_name)
	    *user = g_strdup (passwd_info->pw_name);
	else {
	    /* This is very unlikely to happen */
	    *user = g_strdup ("anonymous");
	}
	endpwent ();
    }

    /* Check if the host comes with a port spec, if so, chop it */
    colon = strchr (rest, ':');
    if (colon) {
	*colon = 0;
	if (sscanf (colon + 1, "%d", port) == 1) {
	    if (*port <= 0 || *port >= 65536)
		*port = default_port;
	} else {
	    while (*(++colon)) {
		switch (*colon) {
		case 'C':
		    *port = 1;
		    break;
		case 'r':
		    *port = 2;
		    break;
		}
	    }
	}
    }
    if (host)
	*host = g_strdup (rest);

    g_free (pcopy);
    return retval;
}
#endif				/* USE_NETCODE */

/*
 * Look up a user or group name from a uid/gid, maintaining a cache.
 * FIXME, for now it's a one-entry cache.
 * FIXME2, the "-993" is to reduce the chance of a hit on the first lookup.
 * This file should be modified for non-unix systems to do something
 * reasonable.
 */

#ifndef TUNMLEN
#define TUNMLEN 256
#endif
#ifndef TGNMLEN
#define TGNMLEN 256
#endif

#define myuid	( my_uid < 0? (my_uid = getuid()): my_uid )
#define	mygid	( my_gid < 0? (my_gid = getgid()): my_gid )

int
vfs_finduid (char *uname)
{
    static int saveuid = -993;
    static char saveuname[TUNMLEN];
    static int my_uid = -993;

    struct passwd *pw;

    if (uname[0] != saveuname[0]	/* Quick test w/o proc call */
	||0 != strncmp (uname, saveuname, TUNMLEN)) {
	strncpy (saveuname, uname, TUNMLEN);
	pw = getpwnam (uname);
	if (pw) {
	    saveuid = pw->pw_uid;
	} else {
	    saveuid = myuid;
	}
    }
    return saveuid;
}

int
vfs_findgid (char *gname)
{
    static int savegid = -993;
    static char savegname[TGNMLEN];
    static int my_gid = -993;

    struct group *gr;

    if (gname[0] != savegname[0]	/* Quick test w/o proc call */
	||0 != strncmp (gname, savegname, TUNMLEN)) {
	strncpy (savegname, gname, TUNMLEN);
	gr = getgrnam (gname);
	if (gr) {
	    savegid = gr->gr_gid;
	} else {
	    savegid = mygid;
	}
    }
    return savegid;
}

/*
 * Create a temporary file with a name resembling the original.
 * This is needed e.g. for local copies requested by extfs.
 * Some extfs scripts may look at the extension.
 * We also protect stupid scripts agains dangerous names.
 */
int
vfs_mkstemps (char **pname, const char *prefix, const char *basename)
{
    const unsigned char *p;
    char *suffix, *q;
    int shift;
    int fd;

    /* Strip directories */
    p = strrchr (basename, PATH_SEP);
    if (!p)
	p = basename;
    else
	p++;

    /* Protection against very long names */
    shift = strlen (p) - (MC_MAXPATHLEN - 16);
    if (shift > 0)
	p += shift;

    suffix = g_malloc (MC_MAXPATHLEN);

    /* Protection against unusual characters */
    q = suffix;
    while (*p && (*p != '#')) {
	if (strchr (".-_@", *p) || isalnum (*p))
	    *q++ = *p;
	p++;
    }
    *q = 0;

    fd = mc_mkstemps (pname, prefix, suffix);
    g_free (suffix);
    return fd;
}

/* Parsing code is used by ftpfs, fish and extfs */
#define MAXCOLS		30

static char *columns[MAXCOLS];	/* Points to the string in column n */
static int column_ptr[MAXCOLS];	/* Index from 0 to the starting positions of the columns */

int
vfs_split_text (char *p)
{
    char *original = p;
    int numcols;

    memset (columns, 0, sizeof (columns));

    for (numcols = 0; *p && numcols < MAXCOLS; numcols++) {
	while (*p == ' ' || *p == '\r' || *p == '\n') {
	    *p = 0;
	    p++;
	}
	columns[numcols] = p;
	column_ptr[numcols] = p - original;
	while (*p && *p != ' ' && *p != '\r' && *p != '\n')
	    p++;
    }
    return numcols;
}

static int
is_num (int idx)
{
    char *column = columns[idx];

    if (!column || column[0] < '0' || column[0] > '9')
	return 0;

    return 1;
}

/* Return 1 for MM-DD-YY and MM-DD-YYYY */
static int
is_dos_date (const char *str)
{
    int len;

    if (!str)
	return 0;

    len = strlen (str);
    if (len != 8 && len != 10)
	return 0;

    if (str[2] != str[5])
	return 0;

    if (!strchr ("\\-/", (int) str[2]))
	return 0;

    return 1;
}

static int
is_week (const char *str, struct tm *tim)
{
    static const char *week = "SunMonTueWedThuFriSat";
    char *pos;

    if (!str)
	return 0;

    if ((pos = strstr (week, str)) != NULL) {
	if (tim != NULL)
	    tim->tm_wday = (pos - week) / 3;
	return 1;
    }
    return 0;
}

static int
is_month (const char *str, struct tm *tim)
{
    static const char *month = "JanFebMarAprMayJunJulAugSepOctNovDec";
    char *pos;

    if (!str)
	return 0;

    if ((pos = strstr (month, str)) != NULL) {
	if (tim != NULL)
	    tim->tm_mon = (pos - month) / 3;
	return 1;
    }
    return 0;
}

/*
 * Check for possible locale's abbreviated month name (Jan..Dec).
 * Any 3 bytes long string without digit and control characters.
 * isalpha() is locale specific, so it cannot be used if current
 * locale is "C" and ftp server use Cyrillic.
 * TODO: Punctuation characters also cannot be part of month name.
 * NB: It is assumed there are no whitespaces in month.
 */
static int
is_localized_month (const unsigned char *month)
{
    int i = 0;
    while ((i < 3) && *month && !isdigit (*month) && !iscntrl (*month)) {
	i++;
	month++;
    }
    return ((i == 3) && (*month == 0));
}

static int
is_time (const char *str, struct tm *tim)
{
    char *p, *p2;

    if (!str)
	return 0;

    if ((p = strchr (str, ':')) && (p2 = strrchr (str, ':'))) {
	if (p != p2) {
	    if (sscanf
		(str, "%2d:%2d:%2d", &tim->tm_hour, &tim->tm_min,
		 &tim->tm_sec) != 3)
		return 0;
	} else {
	    if (sscanf (str, "%2d:%2d", &tim->tm_hour, &tim->tm_min) != 2)
		return 0;
	}
    } else
	return 0;

    return 1;
}

static int
is_year (char *str, struct tm *tim)
{
    long year;

    if (!str)
	return 0;

    if (strchr (str, ':'))
	return 0;

    if (strlen (str) != 4)
	return 0;

    if (sscanf (str, "%ld", &year) != 1)
	return 0;

    if (year < 1900 || year > 3000)
	return 0;

    tim->tm_year = (int) (year - 1900);

    return 1;
}

/*
 * FIXME: this is broken. Consider following entry:
 * -rwx------   1 root     root            1 Aug 31 10:04 2904 1234
 * where "2904 1234" is filename. Well, this code decodes it as year :-(.
 */

int
vfs_parse_filetype (char c)
{
    switch (c) {
    case 'd':
	return S_IFDIR;
    case 'b':
	return S_IFBLK;
    case 'c':
	return S_IFCHR;
    case 'l':
	return S_IFLNK;
    case 's':			/* Socket */
#ifdef S_IFSOCK
	return S_IFSOCK;
#else
	/* If not supported, we fall through to IFIFO */
	return S_IFIFO;
#endif
    case 'D':			/* Solaris door */
#ifdef S_IFDOOR
	return S_IFDOOR;
#else
	return S_IFIFO;
#endif
    case 'p':
	return S_IFIFO;
    case 'm':
    case 'n':			/* Don't know what these are :-) */
    case '-':
    case '?':
	return S_IFREG;
    default:
	return -1;
    }
}

int
vfs_parse_filemode (const char *p)
{				/* converts rw-rw-rw- into 0666 */
    int res = 0;
    switch (*(p++)) {
    case 'r':
	res |= 0400;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'w':
	res |= 0200;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'x':
	res |= 0100;
	break;
    case 's':
	res |= 0100 | S_ISUID;
	break;
    case 'S':
	res |= S_ISUID;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'r':
	res |= 0040;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'w':
	res |= 0020;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'x':
	res |= 0010;
	break;
    case 's':
	res |= 0010 | S_ISGID;
	break;
    case 'l':			/* Solaris produces these */
    case 'S':
	res |= S_ISGID;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'r':
	res |= 0004;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'w':
	res |= 0002;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    switch (*(p++)) {
    case 'x':
	res |= 0001;
	break;
    case 't':
	res |= 0001 | S_ISVTX;
	break;
    case 'T':
	res |= S_ISVTX;
	break;
    case '-':
	break;
    default:
	return -1;
    }
    return res;
}

/* This function parses from idx in the columns[] array */
int
vfs_parse_filedate (int idx, time_t *t)
{
    char *p;
    struct tm tim;
    int d[3];
    int got_year = 0;
    int l10n = 0;		/* Locale's abbreviated month name */
    time_t current_time;
    struct tm *local_time;

    /* Let's setup default time values */
    current_time = time (NULL);
    local_time = localtime (&current_time);
    tim.tm_mday = local_time->tm_mday;
    tim.tm_mon = local_time->tm_mon;
    tim.tm_year = local_time->tm_year;

    tim.tm_hour = 0;
    tim.tm_min = 0;
    tim.tm_sec = 0;
    tim.tm_isdst = -1;		/* Let mktime() try to guess correct dst offset */

    p = columns[idx++];

    /* We eat weekday name in case of extfs */
    if (is_week (p, &tim))
	p = columns[idx++];

    /* Month name */
    if (is_month (p, &tim)) {
	/* And we expect, it followed by day number */
	if (is_num (idx))
	    tim.tm_mday = (int) atol (columns[idx++]);
	else
	    return 0;		/* No day */

    } else {
	/* We usually expect:
	   Mon DD hh:mm
	   Mon DD  YYYY
	   But in case of extfs we allow these date formats:
	   Mon DD YYYY hh:mm
	   Mon DD hh:mm YYYY
	   Wek Mon DD hh:mm:ss YYYY
	   MM-DD-YY hh:mm
	   where Mon is Jan-Dec, DD, MM, YY two digit day, month, year,
	   YYYY four digit year, hh, mm, ss two digit hour, minute or second. */

	/* Special case with MM-DD-YY or MM-DD-YYYY */
	if (is_dos_date (p)) {
	    p[2] = p[5] = '-';

	    if (sscanf (p, "%2d-%2d-%d", &d[0], &d[1], &d[2]) == 3) {
		/* Months are zero based */
		if (d[0] > 0)
		    d[0]--;

		if (d[2] > 1900) {
		    d[2] -= 1900;
		} else {
		    /* Y2K madness */
		    if (d[2] < 70)
			d[2] += 100;
		}

		tim.tm_mon = d[0];
		tim.tm_mday = d[1];
		tim.tm_year = d[2];
		got_year = 1;
	    } else
		return 0;	/* sscanf failed */
	} else {
	    /* Locale's abbreviated month name followed by day number */
	    if (is_localized_month (p) && (is_num (idx++)))
		l10n = 1;
	    else
		return 0;	/* unsupported format */
	}
    }

    /* Here we expect to find time and/or year */

    if (is_num (idx)) {
	if (is_time (columns[idx], &tim)
	    || (got_year = is_year (columns[idx], &tim))) {
	    idx++;

	    /* This is a special case for ctime() or Mon DD YYYY hh:mm */
	    if (is_num (idx) && (columns[idx + 1][0])) {
		if (got_year) {
		    if (is_time (columns[idx], &tim))
			idx++;	/* time also */
		} else {
		    if ((got_year = is_year (columns[idx], &tim)))
			idx++;	/* year also */
		}
	    }
	}			/* only time or date */
    } else
	return 0;		/* Nor time or date */

    /*
     * If the date is less than 6 months in the past, it is shown without year
     * other dates in the past or future are shown with year but without time
     * This does not check for years before 1900 ... I don't know, how
     * to represent them at all
     */
    if (!got_year && local_time->tm_mon < 6
	&& local_time->tm_mon < tim.tm_mon
	&& tim.tm_mon - local_time->tm_mon >= 6)

	tim.tm_year--;

    if (l10n || (*t = mktime (&tim)) < 0)
	*t = 0;
    return idx;
}

int
vfs_parse_ls_lga (const char *p, struct stat *s, char **filename,
		  char **linkname)
{
    int idx, idx2, num_cols;
    int i;
    char *p_copy = NULL;
    char *t = NULL;
    const char *line = p;

    if (strncmp (p, "total", 5) == 0)
	return 0;

    if ((i = vfs_parse_filetype (*(p++))) == -1)
	goto error;

    s->st_mode = i;
    if (*p == ' ')		/* Notwell 4 */
	p++;
    if (*p == '[') {
	if (strlen (p) <= 8 || p[8] != ']')
	    goto error;
	/* Should parse here the Notwell permissions :) */
	if (S_ISDIR (s->st_mode))
	    s->st_mode |=
		(S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR | S_IXUSR | S_IXGRP
		 | S_IXOTH);
	else
	    s->st_mode |= (S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR);
	p += 9;
    } else {
	if ((i = vfs_parse_filemode (p)) == -1)
	    goto error;
	s->st_mode |= i;
	p += 9;

	/* This is for an extra ACL attribute (HP-UX) */
	if (*p == '+')
	    p++;
    }

    p_copy = g_strdup (p);
    num_cols = vfs_split_text (p_copy);

    s->st_nlink = atol (columns[0]);
    if (s->st_nlink <= 0)
	goto error;

    if (!is_num (1))
	s->st_uid = vfs_finduid (columns[1]);
    else
	s->st_uid = (uid_t) atol (columns[1]);

    /* Mhm, the ls -lg did not produce a group field */
    for (idx = 3; idx <= 5; idx++)
	if (is_month (columns[idx], NULL) || is_week (columns[idx], NULL)
	    || is_dos_date (columns[idx])
	    || is_localized_month (columns[idx]))
	    break;

    if (idx == 6
	|| (idx == 5 && !S_ISCHR (s->st_mode) && !S_ISBLK (s->st_mode)))
	goto error;

    /* We don't have gid */
    if (idx == 3
	|| (idx == 4 && (S_ISCHR (s->st_mode) || S_ISBLK (s->st_mode))))
	idx2 = 2;
    else {
	/* We have gid field */
	if (is_num (2))
	    s->st_gid = (gid_t) atol (columns[2]);
	else
	    s->st_gid = vfs_findgid (columns[2]);
	idx2 = 3;
    }

    /* This is device */
    if (S_ISCHR (s->st_mode) || S_ISBLK (s->st_mode)) {
	int maj, min;

	if (!is_num (idx2) || sscanf (columns[idx2], " %d,", &maj) != 1)
	    goto error;

	if (!is_num (++idx2) || sscanf (columns[idx2], " %d", &min) != 1)
	    goto error;

#ifdef HAVE_STRUCT_STAT_ST_RDEV
	s->st_rdev = ((maj & 0xff) << 8) | (min & 0xffff00ff);
#endif
	s->st_size = 0;

    } else {
	/* Common file size */
	if (!is_num (idx2))
	    goto error;

	s->st_size = (size_t) atol (columns[idx2]);
#ifdef HAVE_STRUCT_STAT_ST_RDEV
	s->st_rdev = 0;
#endif
    }

    idx = vfs_parse_filedate (idx, &s->st_mtime);
    if (!idx)
	goto error;
    /* Use resulting time value */
    s->st_atime = s->st_ctime = s->st_mtime;
    /* s->st_dev and s->st_ino must be initialized by vfs_s_new_inode () */
#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
    s->st_blksize = 512;
#endif
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
    s->st_blocks = (s->st_size + 511) / 512;
#endif

    for (i = idx + 1, idx2 = 0; i < num_cols; i++)
	if (strcmp (columns[i], "->") == 0) {
	    idx2 = i;
	    break;
	}

    if (((S_ISLNK (s->st_mode) || (num_cols == idx + 3 && s->st_nlink > 1)))	/* Maybe a hardlink? (in extfs) */
	&&idx2) {

	if (filename) {
	    *filename =
		g_strndup (p + column_ptr[idx],
			   column_ptr[idx2] - column_ptr[idx] - 1);
	}
	if (linkname) {
	    t = g_strdup (p + column_ptr[idx2 + 1]);
	    *linkname = t;
	}
    } else {
	/* Extract the filename from the string copy, not from the columns
	 * this way we have a chance of entering hidden directories like ". ."
	 */
	if (filename) {
	    /*
	     * filename = g_strdup (columns [idx++]);
	     */

	    t = g_strdup (p + column_ptr[idx]);
	    *filename = t;
	}
	if (linkname)
	    *linkname = NULL;
    }

    if (t) {
	int p = strlen (t);
	if ((--p > 0) && (t[p] == '\r' || t[p] == '\n'))
	    t[p] = 0;
	if ((--p > 0) && (t[p] == '\r' || t[p] == '\n'))
	    t[p] = 0;
    }

    g_free (p_copy);
    return 1;

  error:
    {
	static int errorcount = 0;

	if (++errorcount < 5) {
	    message (1, _("Cannot parse:"),
		     (p_copy && *p_copy) ? p_copy : line);
	} else if (errorcount == 5)
	    message (1, _("Error"),
		     _("More parsing errors will be ignored."));
    }

    g_free (p_copy);
    return 0;
}

void
vfs_die (const char *m)
{
    message (1, _("Internal error:"), m);
    exit (1);
}

char *
vfs_get_password (char *msg)
{
    return (char *) input_dialog (msg, _("Password:"), INPUT_PASSWORD);
}