#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "canonicalize.h"
#ifdef STDC_HEADERS
# include <stdlib.h>
#else
void free ();
#endif
#if defined STDC_HEADERS || defined HAVE_STRING_H
# include <string.h>
#else
# include <strings.h>
#endif
#if HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#include <sys/stat.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <errno.h>
#include <stddef.h>
#include "cycle-check.h"
#include "filenamecat.h"
#include "stat-macros.h"
#include "xalloc.h"
#include "xgetcwd.h"
#ifndef __set_errno
# define __set_errno(Val) errno = (Val)
#endif
#include "pathmax.h"
#include "xreadlink.h"
#if !HAVE_CANONICALIZE_FILE_NAME
char *
canonicalize_file_name (const char *name)
{
# if HAVE_RESOLVEPATH
char *resolved, *extra_buf = NULL;
size_t resolved_size;
ssize_t resolved_len;
if (name == NULL)
{
__set_errno (EINVAL);
return NULL;
}
if (name[0] == '\0')
{
__set_errno (ENOENT);
return NULL;
}
if (name[0] != '/')
{
char *wd;
if (!(wd = xgetcwd ()))
return NULL;
extra_buf = file_name_concat (wd, name, NULL);
name = extra_buf;
free (wd);
}
resolved_size = strlen (name);
while (1)
{
resolved_size = 2 * resolved_size + 1;
resolved = xmalloc (resolved_size);
resolved_len = resolvepath (name, resolved, resolved_size);
if (resolved_len < 0)
{
free (resolved);
free (extra_buf);
return NULL;
}
if (resolved_len < resolved_size)
break;
free (resolved);
}
free (extra_buf);
resolved[resolved_len] = '\0';
return resolved;
# else
return canonicalize_filename_mode (name, CAN_EXISTING);
# endif
}
#endif
char *
canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
{
char *rname, *dest, *extra_buf = NULL;
char const *start;
char const *end;
char const *rname_limit;
size_t extra_len = 0;
struct cycle_check_state cycle_state;
if (name == NULL)
{
__set_errno (EINVAL);
return NULL;
}
if (name[0] == '\0')
{
__set_errno (ENOENT);
return NULL;
}
if (name[0] != '/')
{
rname = xgetcwd ();
if (!rname)
return NULL;
dest = strchr (rname, '\0');
if (dest - rname < PATH_MAX)
{
char *p = xrealloc (rname, PATH_MAX);
dest = p + (dest - rname);
rname = p;
rname_limit = rname + PATH_MAX;
}
else
{
rname_limit = dest;
}
}
else
{
rname = xmalloc (PATH_MAX);
rname_limit = rname + PATH_MAX;
rname[0] = '/';
dest = rname + 1;
}
cycle_check_init (&cycle_state);
for (start = end = name; *start; start = end)
{
while (*start == '/')
++start;
for (end = start; *end && *end != '/'; ++end)
;
if (end - start == 0)
break;
else if (end - start == 1 && start[0] == '.')
;
else if (end - start == 2 && start[0] == '.' && start[1] == '.')
{
if (dest > rname + 1)
while ((--dest)[-1] != '/');
}
else
{
struct stat st;
if (dest[-1] != '/')
*dest++ = '/';
if (dest + (end - start) >= rname_limit)
{
ptrdiff_t dest_offset = dest - rname;
size_t new_size = rname_limit - rname;
if (end - start + 1 > PATH_MAX)
new_size += end - start + 1;
else
new_size += PATH_MAX;
rname = xrealloc (rname, new_size);
rname_limit = rname + new_size;
dest = rname + dest_offset;
}
dest = memcpy (dest, start, end - start);
dest += end - start;
*dest = '\0';
if (lstat (rname, &st) != 0)
{
if (can_mode == CAN_EXISTING)
goto error;
if (can_mode == CAN_ALL_BUT_LAST && *end)
goto error;
st.st_mode = 0;
}
if (S_ISLNK (st.st_mode))
{
char *buf;
size_t n, len;
if (cycle_check (&cycle_state, &st))
{
__set_errno (ELOOP);
if (can_mode == CAN_MISSING)
continue;
else
goto error;
}
buf = xreadlink (rname, st.st_size);
if (!buf)
{
if (can_mode == CAN_MISSING)
continue;
else
goto error;
}
n = strlen (buf);
len = strlen (end);
if (!extra_len)
{
extra_len =
((n + len + 1) > PATH_MAX) ? (n + len + 1) : PATH_MAX;
extra_buf = xmalloc (extra_len);
}
else if ((n + len + 1) > extra_len)
{
extra_len = n + len + 1;
extra_buf = xrealloc (extra_buf, extra_len);
}
memmove (&extra_buf[n], end, len + 1);
name = end = memcpy (extra_buf, buf, n);
if (buf[0] == '/')
dest = rname + 1;
else
if (dest > rname + 1)
while ((--dest)[-1] != '/');
free (buf);
}
else
{
if (!S_ISDIR (st.st_mode) && *end && (can_mode != CAN_MISSING))
{
errno = ENOTDIR;
goto error;
}
}
}
}
if (dest > rname + 1 && dest[-1] == '/')
--dest;
*dest = '\0';
free (extra_buf);
return rname;
error:
free (extra_buf);
free (rname);
return NULL;
}