X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fcanonicalize.c;h=4f348398fd69ae516396313d18ac294a4ca3dde3;hb=d5ac73d5b20cff8aacc9a1bce8f558415a71b9e1;hp=822fe6f75ae6640d81b40eda02ba3791d031d6b6;hpb=e7dff5cd0a07f0aa94761f9823d0bd9939da0d03;p=gnulib.git

diff --git a/lib/canonicalize.c b/lib/canonicalize.c
index 822fe6f75..4f348398f 100644
--- a/lib/canonicalize.c
+++ b/lib/canonicalize.c
@@ -1,10 +1,10 @@
 /* Return the canonical absolute name of a given file.
-   Copyright (C) 1996-2005 Free Software Foundation, Inc.
+   Copyright (C) 1996-2008 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
@@ -12,27 +12,14 @@
    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,
-   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
 
 #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
+#include <stdlib.h>
+#include <string.h>
 
 #if HAVE_SYS_PARAM_H
 # include <sys/param.h>
@@ -40,30 +27,31 @@ void free ();
 
 #include <sys/stat.h>
 
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <unistd.h>
 
 #include <errno.h>
 #include <stddef.h>
 
-#include "cycle-check.h"
-#include "path-concat.h"
-#include "stat-macros.h"
+#include "file-set.h"
+#include "filenamecat.h"
+#include "hash-triple.h"
 #include "xalloc.h"
 #include "xgetcwd.h"
 
+#ifndef ELOOP
+# define ELOOP 0
+#endif
 #ifndef __set_errno
 # define __set_errno(Val) errno = (Val)
 #endif
 
 #include "pathmax.h"
-#include "xreadlink.h"
+#include "areadlink.h"
 
-#if !HAVE_CANONICALIZE_FILE_NAME
+#if !(HAVE_CANONICALIZE_FILE_NAME || 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 *
@@ -89,7 +77,7 @@ canonicalize_file_name (const char *name)
 
   /* 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.  */
+     directory if the file name is not absolute.  */
   if (name[0] != '/')
     {
       char *wd;
@@ -97,7 +85,7 @@ canonicalize_file_name (const char *name)
       if (!(wd = xgetcwd ()))
 	return NULL;
 
-      extra_buf = path_concat (wd, name, NULL);
+      extra_buf = file_name_concat (wd, name, NULL);
       name = extra_buf;
       free (wd);
     }
@@ -134,18 +122,44 @@ canonicalize_file_name (const char *name)
 }
 #endif /* !HAVE_CANONICALIZE_FILE_NAME */
 
+/* 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)
+    {
+      size_t initial_capacity = 7;
+      *ht = hash_initialize (initial_capacity,
+			    NULL,
+			    triple_hash,
+			    triple_compare_ino_str,
+			    triple_free);
+      if (*ht == NULL)
+	xalloc_die ();
+    }
+
+  if (seen_file (*ht, filename, st))
+    return true;
+
+  record_file (*ht, filename, st);
+  return false;
+}
+
 /* 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
+   does not contain any `.', `..' components nor any repeated file name
+   separators ('/') or 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;
 
   if (name == NULL)
     {
@@ -161,38 +175,37 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 
   if (name[0] != '/')
     {
-      rpath = xgetcwd ();
-      if (!rpath)
+      rname = xgetcwd ();
+      if (!rname)
 	return NULL;
-      dest = strchr (rpath, '\0');
-      if (dest - rpath < PATH_MAX)
+      dest = strchr (rname, '\0');
+      if (dest - rname < PATH_MAX)
 	{
-	  char *p = xrealloc (rpath, PATH_MAX);
-	  dest = p + (dest - rpath);
-	  rpath = p;
-	  rpath_limit = rpath + 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;
 	}
     }
   else
     {
-      rpath = xmalloc (PATH_MAX);
-      rpath_limit = rpath + PATH_MAX;
-      rpath[0] = '/';
-      dest = rpath + 1;
+      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)
     {
-      /* Skip sequence of multiple path-separators.  */
+      /* Skip sequence of multiple file name separators.  */
       while (*start == '/')
 	++start;
 
-      /* Find end of path component.  */
+      /* Find end of component.  */
       for (end = start; *end && *end != '/'; ++end)
 	/* Nothing.  */;
 
@@ -203,7 +216,7 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
       else if (end - start == 2 && start[0] == '.' && start[1] == '.')
 	{
 	  /* Back up to previous component, ignore if at root already.  */
-	  if (dest > rpath + 1)
+	  if (dest > rname + 1)
 	    while ((--dest)[-1] != '/');
 	}
       else
@@ -213,26 +226,26 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	  if (dest[-1] != '/')
 	    *dest++ = '/';
 
-	  if (dest + (end - start) >= rpath_limit)
+	  if (dest + (end - start) >= rname_limit)
 	    {
-	      ptrdiff_t dest_offset = dest - rpath;
-	      size_t new_size = rpath_limit - rpath;
+	      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;
-	      rpath = xrealloc (rpath, new_size);
-	      rpath_limit = rpath + new_size;
+	      rname = xrealloc (rname, new_size);
+	      rname_limit = rname + new_size;
 
-	      dest = rpath + dest_offset;
+	      dest = rname + dest_offset;
 	    }
 
 	  dest = memcpy (dest, start, end - start);
 	  dest += end - start;
 	  *dest = '\0';
 
-	  if (lstat (rpath, &st) < 0)
+	  if (lstat (rname, &st) != 0)
 	    {
 	      if (can_mode == CAN_EXISTING)
 		goto error;
@@ -246,7 +259,11 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	      char *buf;
 	      size_t n, len;
 
-	      if (cycle_check (&cycle_state, &st))
+	      /* 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))
 		{
 		  __set_errno (ELOOP);
 		  if (can_mode == CAN_MISSING)
@@ -255,10 +272,10 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 		    goto error;
 		}
 
-	      buf = xreadlink (rpath, st.st_size);
+	      buf = areadlink_with_size (rname, st.st_size);
 	      if (!buf)
 		{
-		  if (can_mode == CAN_MISSING)
+		  if (can_mode == CAN_MISSING && errno != ENOMEM)
 		    continue;
 		  else
 		    goto error;
@@ -284,10 +301,10 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	      name = end = memcpy (extra_buf, buf, n);
 
 	      if (buf[0] == '/')
-		dest = rpath + 1;	/* It's an absolute symlink */
+		dest = rname + 1;	/* It's an absolute symlink */
 	      else
 		/* Back up to previous component, ignore if at root already: */
-		if (dest > rpath + 1)
+		if (dest > rname + 1)
 		  while ((--dest)[-1] != '/');
 
 	      free (buf);
@@ -302,15 +319,19 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	    }
 	}
     }
-  if (dest > rpath + 1 && dest[-1] == '/')
+  if (dest > rname + 1 && dest[-1] == '/')
     --dest;
   *dest = '\0';
 
   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);
   return NULL;
 }