(make_path): Chdir to `/' before starting if necessary.

Call save_cwd before while loop rather than from first iteration inside it.

diff --git a/lib/makepath.c b/lib/makepath.c
index 17844318a51e653d19e8626c7ebc0be8ab8fa6fc..4218e90c6035f0350e6984ab3911b8b1a71d2805 100644 (file)
--- a/lib/makepath.c
+++ b/lib/makepath.c
@@ -87,7 +87,7 @@ void strip_trailing_slashes ();
     {                                                  \
       /* We're done operating on basename_dir.         \
         Restore working directory.  */                 \
-      if (saved_cwd)                                   \
+      if (do_chdir)                                    \
        {                                               \
          int fail = restore_cwd (&cwd, NULL, NULL);    \
          free_cwd (&cwd);                              \
@@ -159,10 +159,9 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
        struct ptr_list *next;
       };
       struct ptr_list *p, *leading_dirs = NULL;
-      int saved_cwd = 0;
+      int do_chdir;            /* Whether to chdir before each mkdir.  */
       struct saved_cwd cwd;
       char *basename_dir;
-      int first_subdir = 1;
       char *dirpath;
 
       /* Temporarily relax umask in case it's overly restrictive.  */
@@ -189,6 +188,16 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
          re_protect = 0;
        }
 
+      /* If we can record the current working directory, we may be able
+        to do the chdir optimization.  */
+      do_chdir = !save_cwd (&cwd);
+
+      /* If we've saved the cwd and DIRPATH is an absolute pathname,
+        we must chdir to `/' in order to enable the chdir optimization.
+         So if chdir ("/") fails, turn off the optimization.  */
+      if (do_chdir && *dirpath == '/' && chdir ("/") < 0)
+       do_chdir = 0;
+
       slash = dirpath;
 
       /* Skip over leading slashes.  */
@@ -204,16 +213,9 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
          if (slash == NULL)
            break;
 
-         if (first_subdir)
-           {
-             first_subdir = 0;
-             saved_cwd = !save_cwd (&cwd);
-           }
-
-         /* If save_cwd could not record the current directory, then don't
-            do the chdir optimization and resort to using full pathnames.  */
-
-         if (!saved_cwd)
+         /* If we're *not* doing chdir before each mkdir, then we have to refer
+            to the target using the full (multi-component) directory name.  */
+         if (!do_chdir)
            basename_dir = dirpath;
 
          *slash = '\0';
@@ -265,7 +267,7 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
             then we can use chdir to change into each directory before
             creating an entry in that directory.  This avoids making
             stat and mkdir process O(n^2) file name components.  */
-         if (saved_cwd && chdir (basename_dir) < 0)
+         if (do_chdir && chdir (basename_dir) < 0)
            {
              error (0, errno, "cannot chdir to directory, %s", dirpath);
              CLEANUP;
@@ -280,7 +282,7 @@ make_path (argpath, mode, parent_mode, owner, group, preserve_existing,
            slash++;
        }
 
-      if (!saved_cwd)
+      if (!do_chdir)
        basename_dir = dirpath;
 
       /* We're done making leading directories.