* prefix.c: (update_path): Strip ".." components when prior dir

[pf3gnuchains/gcc-fork.git] / gcc / prefix.c

diff --git a/gcc/prefix.c b/gcc/prefix.c
index 8890673..c8f0b98 100644 (file)
--- a/gcc/prefix.c
+++ b/gcc/prefix.c
@@ -1,5 +1,6 @@
 /* Utility to update paths from internal to external forms.
-   Copyright (C) 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+   Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002
+   Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -42,7 +43,7 @@ Boston, MA 02111-1307, USA.  */
    be considered a "key" and looked up as follows:
 
    -- If this is a Win32 OS, then the Registry will be examined for
-      an entry of "key" in 
+      an entry of "key" in
 
       HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<KEY>
 
@@ -58,7 +59,7 @@ Boston, MA 02111-1307, USA.  */
    as an environment variable, whose value will be returned.
 
    Once all this is done, any '/' will be converted to DIR_SEPARATOR,
-   if they are different. 
+   if they are different.
 
    NOTE:  using resolve_keyed_path under Win32 requires linking with
    advapi32.dll.  */
@@ -149,10 +150,10 @@ lookup_key (key)
                             KEY_READ, &reg_key);
 
       if (res != ERROR_SUCCESS)
-        {
-          reg_key = (HKEY) INVALID_HANDLE_VALUE;
-          return 0;
-        }
+       {
+         reg_key = (HKEY) INVALID_HANDLE_VALUE;
+         return 0;
+       }
     }
 
   size = 32;
@@ -251,7 +252,7 @@ update_path (path, key)
   const char *path;
   const char *key;
 {
-  char *result;
+  char *result, *p;
 
   if (! strncmp (path, std_prefix, strlen (std_prefix)) && key != 0)
     {
@@ -271,9 +272,70 @@ update_path (path, key)
   else
     result = xstrdup (path);
 
+#ifndef ALWAYS_STRIP_DOTDOT
+#define ALWAYS_STRIP_DOTDOT 0
+#endif
+
+  p = result;
+  while (1)
+    {
+      char *src, *dest;
+
+      p = strchr (p, '.');
+      if (p == NULL)
+       break;
+      /* Get rid of a leading `./' and replace `/./' with `/'.  */
+      if (IS_DIR_SEPARATOR (p[1])
+         && (p == result || IS_DIR_SEPARATOR (p[-1])))
+       {
+         src = p + 2;
+         /* Be careful about .//foo  */
+         while (IS_DIR_SEPARATOR (*src))
+           ++src;
+         dest = p;
+         while ((*dest++ = *src++) != 0)
+           ;
+       }
+      /* Look for `/../'  */
+      else if (p[1] == '.'
+              && IS_DIR_SEPARATOR (p[2])
+              && (p != result && IS_DIR_SEPARATOR (p[-1])))
+       {
+         *p = 0;
+         if (!ALWAYS_STRIP_DOTDOT && access (result, X_OK) == 0)
+           {
+             *p = '.';
+             p += 3;
+           }
+         else
+           {
+             /* We can't access the dir, so we won't be able to
+                access dir/.. either.  Strip out dir/..  We know dir
+                isn't `.' because we've rid ourselves of `.' path
+                components above.  */
+             dest = p - 1;
+             while (dest != result && IS_DIR_SEPARATOR (*dest))
+               --dest;
+             while (dest != result && IS_DIR_SEPARATOR (dest[-1]))
+               --dest;
+             /* Don't strip leading `/'.  */
+             while (IS_DIR_SEPARATOR (*dest))
+               ++dest;
+             src = p + 3;
+             while (IS_DIR_SEPARATOR (*src))
+               ++src;
+             p = dest;
+             while ((*dest++ = *src++) != 0)
+               ;
+           }
+       }
+      else
+       ++p;
+    }
+
 #ifdef UPDATE_PATH_HOST_CANONICALIZE
   /* Perform host dependent canonicalization when needed.  */
-  UPDATE_PATH_HOST_CANONICALIZE (path);
+  UPDATE_PATH_HOST_CANONICALIZE (result);
 #endif
 
 #ifdef DIR_SEPARATOR_2