/* Return the canonical absolute name of a given file.
- Copyright (C) 1996-2004 Free Software Foundation, Inc.
+ Copyright (C) 1996-2013 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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.
+ the Free Software Foundation; either version 3 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
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; see the file COPYING.
- If not, write to the Free Software Foundation,
- 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#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
+#include <config.h>
-#if HAVE_SYS_PARAM_H
-# include <sys/param.h>
-#endif
-
-#include <sys/stat.h>
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include "canonicalize.h"
#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
-#include "cycle-check.h"
-#include "path-concat.h"
-#include "stat-macros.h"
+#include "areadlink.h"
+#include "file-set.h"
+#include "hash-triple.h"
+#include "pathmax.h"
#include "xalloc.h"
#include "xgetcwd.h"
+#include "dosname.h"
+
+#define MULTIPLE_BITS_SET(i) (((i) & ((i) - 1)) != 0)
-#ifndef __set_errno
-# define __set_errno(Val) errno = (Val)
+/* In this file, we cannot handle file names longer than PATH_MAX.
+ On systems with no file name length limit, use a fallback. */
+#ifndef PATH_MAX
+# define PATH_MAX 8192
#endif
-/* If __PTRDIFF_TYPE__ is
- defined, as with GNU C, use that; that way we don't pollute the
- namespace with <stddef.h>'s symbols. Otherwise, if <stddef.h> is
- available, include it and use ptrdiff_t. In traditional C, long is
- the best that we can do. */
+#ifndef DOUBLE_SLASH_IS_DISTINCT_ROOT
+# define DOUBLE_SLASH_IS_DISTINCT_ROOT 0
+#endif
-#ifdef __PTRDIFF_TYPE__
-# define PTR_INT_TYPE __PTRDIFF_TYPE__
+#if ISSLASH ('\\')
+# define SLASHES "/\\"
#else
-# ifdef HAVE_STDDEF_H
-# include <stddef.h>
-# define PTR_INT_TYPE ptrdiff_t
-# else
-# define PTR_INT_TYPE long
-# endif
+# define SLASHES "/"
#endif
-#include "canonicalize.h"
-#include "pathmax.h"
-#include "stat-macros.h"
-#include "xreadlink.h"
-
-#if !HAVE_CANONICALIZE_FILE_NAME
+#if !((HAVE_CANONICALIZE_FILE_NAME && FUNC_REALPATH_WORKS) \
+ || GNULIB_CANONICALIZE_LGPL)
/* Return the canonical absolute name of file NAME. A canonical name
- does not contain any `.', `..' components nor any repeated path
- separators ('/') or symlinks. All path components must exist.
+ does not contain any ".", ".." components nor any repeated file name
+ separators ('/') or symlinks. All components must exist.
The result is malloc'd. */
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;
- }
-
- /* All known hosts with resolvepath (e.g. Solaris 7) don't turn
- relative names into absolute ones, so prepend the working
- directory if the path is not absolute. */
- if (name[0] != '/')
- {
- char *wd;
-
- if (!(wd = xgetcwd ()))
- return NULL;
-
- extra_buf = path_concat (wd, name, NULL);
- name = extra_buf;
- free (wd);
- }
+ return canonicalize_filename_mode (name, CAN_EXISTING);
+}
+#endif /* !HAVE_CANONICALIZE_FILE_NAME */
- resolved_size = strlen (name);
- while (1)
+/* Return true if we've already seen the triple, <FILENAME, dev, ino>.
+ If *HT is not initialized, initialize it. */
+static bool
+seen_triple (Hash_table **ht, char const *filename, struct stat const *st)
+{
+ if (*ht == NULL)
{
- 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);
+ size_t initial_capacity = 7;
+ *ht = hash_initialize (initial_capacity,
+ NULL,
+ triple_hash,
+ triple_compare_ino_str,
+ triple_free);
+ if (*ht == NULL)
+ xalloc_die ();
}
- free (extra_buf);
-
- /* NUL-terminate the resulting name. */
- resolved[resolved_len] = '\0';
+ if (seen_file (*ht, filename, st))
+ return true;
- return resolved;
-
-# else
-
- return canonicalize_filename_mode (name, CAN_EXISTING);
-
-# endif /* !HAVE_RESOLVEPATH */
+ record_file (*ht, filename, st);
+ return false;
}
-#endif /* !HAVE_CANONICALIZE_FILE_NAME */
-/* Return the canonical absolute name of file NAME. A canonical name
- does not contain any `.', `..' components nor any repeated path
- separators ('/') or symlinks. Whether path components must exist
- or not depends on canonicalize mode. The result is malloc'd. */
+/* Return the canonical absolute name of file NAME, while treating
+ missing elements according to CAN_MODE. A canonical name
+ does not contain any ".", ".." components nor any repeated file name
+ separators ('/') or, depending on other CAN_MODE flags, symlinks.
+ Whether components must exist or not depends on canonicalize mode.
+ The result is malloc'd. */
char *
canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
{
- char *rpath, *dest, *extra_buf = NULL;
- const char *start, *end, *rpath_limit;
+ 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;
+ Hash_table *ht = NULL;
+ int saved_errno;
+ int can_flags = can_mode & ~CAN_MODE_MASK;
+ bool logical = can_flags & CAN_NOLINKS;
+ size_t prefix_len;
+
+ can_mode &= CAN_MODE_MASK;
+
+ if (MULTIPLE_BITS_SET (can_mode))
+ {
+ errno = EINVAL;
+ return NULL;
+ }
if (name == NULL)
{
- __set_errno (EINVAL);
+ errno = EINVAL;
return NULL;
}
if (name[0] == '\0')
{
- __set_errno (ENOENT);
+ errno = ENOENT;
return NULL;
}
- if (name[0] != '/')
+ /* This is always zero for Posix hosts, but can be 2 for MS-Windows
+ and MS-DOS X:/foo/bar file names. */
+ prefix_len = FILE_SYSTEM_PREFIX_LEN (name);
+
+ if (!IS_ABSOLUTE_FILE_NAME (name))
{
- rpath = xgetcwd ();
- if (!rpath)
- return NULL;
- dest = strchr (rpath, '\0');
- if (dest - rpath < PATH_MAX)
- {
- char *p = xrealloc (rpath, PATH_MAX);
- dest = p + (dest - rpath);
- rpath = p;
- rpath_limit = rpath + PATH_MAX;
- }
+ 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
- {
- rpath_limit = dest;
- }
+ {
+ rname_limit = dest;
+ }
+ start = name;
+ prefix_len = FILE_SYSTEM_PREFIX_LEN (rname);
}
else
{
- rpath = xmalloc (PATH_MAX);
- rpath_limit = rpath + PATH_MAX;
- rpath[0] = '/';
- dest = rpath + 1;
+ rname = xmalloc (PATH_MAX);
+ rname_limit = rname + PATH_MAX;
+ dest = rname;
+ if (prefix_len)
+ {
+ memcpy (rname, name, prefix_len);
+ dest += prefix_len;
+ }
+ *dest++ = '/';
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT)
+ {
+ if (ISSLASH (name[1]) && !ISSLASH (name[2]) && !prefix_len)
+ *dest++ = '/';
+ *dest = '\0';
+ }
+ start = name + prefix_len;
}
- cycle_check_init (&cycle_state);
- for (start = end = name; *start; start = end)
+ for ( ; *start; start = end)
{
- /* Skip sequence of multiple path-separators. */
- while (*start == '/')
- ++start;
+ /* Skip sequence of multiple file name separators. */
+ while (ISSLASH (*start))
+ ++start;
- /* Find end of path component. */
- for (end = start; *end && *end != '/'; ++end)
- /* Nothing. */;
+ /* Find end of component. */
+ for (end = start; *end && !ISSLASH (*end); ++end)
+ /* Nothing. */;
if (end - start == 0)
- break;
+ break;
else if (end - start == 1 && start[0] == '.')
- /* nothing */;
+ /* nothing */;
else if (end - start == 2 && start[0] == '.' && start[1] == '.')
- {
- /* Back up to previous component, ignore if at root already. */
- if (dest > rpath + 1)
- while ((--dest)[-1] != '/');
- }
+ {
+ /* Back up to previous component, ignore if at root already. */
+ if (dest > rname + prefix_len + 1)
+ for (--dest; dest > rname && !ISSLASH (dest[-1]); --dest)
+ continue;
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
+ && !prefix_len && ISSLASH (*dest) && !ISSLASH (dest[1]))
+ dest++;
+ }
else
- {
- struct stat st;
-
- if (dest[-1] != '/')
- *dest++ = '/';
-
- if (dest + (end - start) >= rpath_limit)
- {
- PTR_INT_TYPE dest_offset = dest - rpath;
- size_t new_size = rpath_limit - rpath;
-
- if (end - start + 1 > PATH_MAX)
- new_size += end - start + 1;
- else
- new_size += PATH_MAX;
- rpath = xrealloc (rpath, new_size);
- rpath_limit = rpath + new_size;
-
- dest = rpath + dest_offset;
- }
-
- dest = memcpy (dest, start, end - start);
- dest += end - start;
- *dest = '\0';
-
- if (lstat (rpath, &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 (rpath, 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);
- }
-
- /* Careful here, end may be a pointer into extra_buf... */
- memmove (&extra_buf[n], end, len + 1);
- name = end = memcpy (extra_buf, buf, n);
-
- if (buf[0] == '/')
- dest = rpath + 1; /* It's an absolute symlink */
- else
- /* Back up to previous component, ignore if at root already: */
- if (dest > rpath + 1)
- while ((--dest)[-1] != '/');
-
- free (buf);
- }
- else
- {
- if (!S_ISDIR (st.st_mode) && *end && (can_mode != CAN_MISSING))
- {
- errno = ENOTDIR;
- goto error;
- }
- }
- }
+ {
+ struct stat st;
+
+ if (!ISSLASH (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 (logical && (can_mode == CAN_MISSING))
+ {
+ /* Avoid the stat in this case as it's inconsequential.
+ i.e. we're neither resolving symlinks or testing
+ component existence. */
+ st.st_mode = 0;
+ }
+ else if ((logical ? stat (rname, &st) : lstat (rname, &st)) != 0)
+ {
+ saved_errno = errno;
+ if (can_mode == CAN_EXISTING)
+ goto error;
+ if (can_mode == CAN_ALL_BUT_LAST)
+ {
+ if (end[strspn (end, SLASHES)] || saved_errno != ENOENT)
+ goto error;
+ continue;
+ }
+ st.st_mode = 0;
+ }
+
+ if (S_ISLNK (st.st_mode))
+ {
+ char *buf;
+ size_t n, len;
+
+ /* Detect loops. We cannot use the cycle-check module here,
+ since it's actually possible to encounter the same symlink
+ more than once in a given traversal. However, encountering
+ the same symlink,NAME pair twice does indicate a loop. */
+ if (seen_triple (&ht, name, &st))
+ {
+ if (can_mode == CAN_MISSING)
+ continue;
+ saved_errno = ELOOP;
+ goto error;
+ }
+
+ buf = areadlink_with_size (rname, st.st_size);
+ if (!buf)
+ {
+ if (can_mode == CAN_MISSING && errno != ENOMEM)
+ continue;
+ saved_errno = errno;
+ 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);
+ }
+
+ /* Careful here, end may be a pointer into extra_buf... */
+ memmove (&extra_buf[n], end, len + 1);
+ name = end = memcpy (extra_buf, buf, n);
+
+ if (IS_ABSOLUTE_FILE_NAME (buf))
+ {
+ size_t pfxlen = FILE_SYSTEM_PREFIX_LEN (buf);
+
+ if (pfxlen)
+ memcpy (rname, buf, pfxlen);
+ dest = rname + pfxlen;
+ *dest++ = '/'; /* It's an absolute symlink */
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT)
+ {
+ if (ISSLASH (buf[1]) && !ISSLASH (buf[2]) && !pfxlen)
+ *dest++ = '/';
+ *dest = '\0';
+ }
+ /* Install the new prefix to be in effect hereafter. */
+ prefix_len = pfxlen;
+ }
+ else
+ {
+ /* Back up to previous component, ignore if at root
+ already: */
+ if (dest > rname + prefix_len + 1)
+ for (--dest; dest > rname && !ISSLASH (dest[-1]); --dest)
+ continue;
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
+ && ISSLASH (*dest) && !ISSLASH (dest[1]) && !prefix_len)
+ dest++;
+ }
+
+ free (buf);
+ }
+ else
+ {
+ if (!S_ISDIR (st.st_mode) && *end && (can_mode != CAN_MISSING))
+ {
+ saved_errno = ENOTDIR;
+ goto error;
+ }
+ }
+ }
}
- if (dest > rpath + 1 && dest[-1] == '/')
+ if (dest > rname + prefix_len + 1 && ISSLASH (dest[-1]))
--dest;
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1 && !prefix_len
+ && ISSLASH (*dest) && !ISSLASH (dest[1]))
+ dest++;
*dest = '\0';
+ if (rname_limit != dest + 1)
+ rname = xrealloc (rname, dest - rname + 1);
free (extra_buf);
- return rpath;
+ if (ht)
+ hash_free (ht);
+ return rname;
error:
free (extra_buf);
- free (rpath);
+ free (rname);
+ if (ht)
+ hash_free (ht);
+ errno = saved_errno;
return NULL;
}
projects / gnulib.git / blobdiff