canonicalize: avoid uninitialized memory use

[gnulib.git] / lib / canonicalize.c

diff --git a/lib/canonicalize.c b/lib/canonicalize.c
index e5b69d9..583c1a4 100644 (file)
--- a/lib/canonicalize.c
+++ b/lib/canonicalize.c
@@ -1,5 +1,5 @@
 /* Return the canonical absolute name of a given file.
-   Copyright (C) 1996-2011 Free Software Foundation, Inc.
+   Copyright (C) 1996-2012 Free Software Foundation, Inc.
 
    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
@@ -46,7 +46,7 @@
 #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 file name
+   does not contain any ".", ".." components nor any repeated file name
    separators ('/') or symlinks.  All components must exist.
    The result is malloc'd.  */
 
@@ -83,8 +83,8 @@ seen_triple (Hash_table **ht, char const *filename, struct stat const *st)
 
 /* 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, depdending on other CAN_MODE flags, symlinks.
+   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.  */
 
@@ -145,8 +145,12 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
       rname_limit = rname + PATH_MAX;
       rname[0] = '/';
       dest = rname + 1;
-      if (DOUBLE_SLASH_IS_DISTINCT_ROOT && name[1] == '/')
-        *dest++ = '/';
+      if (DOUBLE_SLASH_IS_DISTINCT_ROOT)
+        {
+          if (name[1] == '/' && name[2] != '/')
+            *dest++ = '/';
+          *dest = '\0';
+        }
     }
 
   for (start = name; *start; start = end)
@@ -169,7 +173,7 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
           if (dest > rname + 1)
             while ((--dest)[-1] != '/');
           if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
-              && *dest == '/')
+              && *dest == '/' && dest[1] != '/')
             dest++;
         }
       else
@@ -267,8 +271,12 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
               if (buf[0] == '/')
                 {
                   dest = rname + 1;     /* It's an absolute symlink */
-                  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && buf[1] == '/')
-                    *dest++ = '/';
+                  if (DOUBLE_SLASH_IS_DISTINCT_ROOT)
+                    {
+                      if (buf[1] == '/' && buf[2] != '/')
+                        *dest++ = '/';
+                      *dest = '\0';
+                    }
                 }
               else
                 {
@@ -277,7 +285,7 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
                   if (dest > rname + 1)
                     while ((--dest)[-1] != '/');
                   if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
-                      && *dest == '/')
+                      && *dest == '/' && dest[1] != '/')
                     dest++;
                 }
 
@@ -295,7 +303,8 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
     }
   if (dest > rname + 1 && dest[-1] == '/')
     --dest;
-  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1 && *dest == '/')
+  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
+      && *dest == '/' && dest[1] != '/')
     dest++;
   *dest = '\0';
   if (rname_limit != dest + 1)