glibc/elf/sln.c

218 lines
4.4 KiB
C

/* `sln' program to create symbolic links between files.
Copyright (C) 1998-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <error.h>
#include <errno.h>
#include <libintl.h>
#include <locale.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include "../version.h"
#define PACKAGE _libc_intl_domainname
#if !defined S_ISDIR && defined S_IFDIR
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif
static int makesymlink (const char *src, const char *dest);
static int makesymlinks (const char *file);
static void usage (void);
int
main (int argc, char **argv)
{
/* Set locale via LC_ALL. */
setlocale (LC_ALL, "");
/* Set the text message domain. */
textdomain (PACKAGE);
switch (argc)
{
case 2:
if (strcmp (argv[1], "--version") == 0) {
printf ("sln %s%s\n", PKGVERSION, VERSION);
return 0;
} else if (strcmp (argv[1], "--help") == 0) {
usage ();
return 0;
}
return makesymlinks (argv [1]);
break;
case 3:
return makesymlink (argv [1], argv [2]);
break;
default:
usage ();
return 1;
break;
}
}
static void
usage (void)
{
printf (_("Usage: sln src dest|file\n\n"));
printf (_("For bug reporting instructions, please see:\n\
%s.\n"), REPORT_BUGS_TO);
}
static int
makesymlinks (const char *file)
{
#ifndef PATH_MAX
#define PATH_MAX 4095
#endif
char *buffer = NULL;
size_t bufferlen = 0;
int ret;
int lineno;
FILE *fp;
if (strcmp (file, "-") == 0)
fp = stdin;
else
{
fp = fopen (file, "r");
if (fp == NULL)
{
fprintf (stderr, _("%s: file open error: %m\n"), file);
return 1;
}
}
ret = 0;
lineno = 0;
while (!feof_unlocked (fp))
{
ssize_t n = getline (&buffer, &bufferlen, fp);
char *src;
char *dest;
char *cp = buffer;
if (n < 0)
break;
if (buffer[n - 1] == '\n')
buffer[n - 1] = '\0';
++lineno;
while (isspace (*cp))
++cp;
if (*cp == '\0')
/* Ignore empty lines. */
continue;
src = cp;
do
++cp;
while (*cp != '\0' && ! isspace (*cp));
if (*cp != '\0')
*cp++ = '\0';
while (isspace (*cp))
++cp;
if (*cp == '\0')
{
fprintf (stderr, _("No target in line %d\n"), lineno);
ret = 1;
continue;
}
dest = cp;
do
++cp;
while (*cp != '\0' && ! isspace (*cp));
if (*cp != '\0')
*cp++ = '\0';
ret |= makesymlink (src, dest);
}
fclose (fp);
return ret;
}
static int
makesymlink (const char *src, const char *dest)
{
struct stat stats;
const char *error;
/* Destination must not be a directory. */
if (lstat (dest, &stats) == 0)
{
if (S_ISDIR (stats.st_mode))
{
fprintf (stderr, _("%s: destination must not be a directory\n"),
dest);
return 1;
}
else if (unlink (dest) && errno != ENOENT)
{
fprintf (stderr, _("%s: failed to remove the old destination\n"),
dest);
return 1;
}
}
else if (errno != ENOENT)
{
error = strerror (errno);
fprintf (stderr, _("%s: invalid destination: %s\n"), dest, error);
return -1;
}
#ifdef S_ISLNK
if (symlink (src, dest) == 0)
#else
if (link (src, dest) == 0)
#endif
{
/* Destination must exist by now. */
if (access (dest, F_OK))
{
error = strerror (errno);
unlink (dest);
fprintf (stderr, _("Invalid link from \"%s\" to \"%s\": %s\n"),
src, dest, error);
return 1;
}
return 0;
}
else
{
error = strerror (errno);
fprintf (stderr, _("Invalid link from \"%s\" to \"%s\": %s\n"),
src, dest, error);
return 1;
}
}