tar: prefer openat-style functions

[chaz/tar] / src / compare.c

diff --git a/src/compare.c b/src/compare.c
index 7df3d9853d9dc7ed4b0f15308213e84c8e26ab42..1ee9bcb19d9f7e3d33ccc783f5b64cfba0cd6955 100644 (file)
--- a/src/compare.c
+++ b/src/compare.c
@@ -1,13 +1,13 @@
 /* Diff files from a tar archive.
 
    Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1999, 2000, 2001,
-   2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+   2003, 2004, 2005, 2006, 2007, 2009, 2010 Free Software Foundation, Inc.
 
    Written by John Gilmore, on 1987-04-30.
 
    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
+   Free Software Foundation; either version 3, or (at your option) any later
    version.
 
    This program is distributed in the hope that it will be useful, but
@@ -66,8 +66,7 @@ report_difference (struct tar_stat_info *st, const char *fmt, ...)
       fprintf (stdlis, "\n");
     }
 
-  if (exit_status == TAREXIT_SUCCESS)
-    exit_status = TAREXIT_DIFFERS;
+  set_exit_status (TAREXIT_DIFFERS);
 }
 
 /* Take a buffer returned by read_and_process and do nothing with it.  */
@@ -123,7 +122,7 @@ read_and_process (struct tar_stat_info *st, int (*processor) (size_t, char *))
   size_t data_size;
   off_t size = st->stat.st_size;
 
-  mv_begin (st);
+  mv_begin_read (st);
   while (size)
     {
       data_block = find_next_block ();
@@ -223,7 +222,9 @@ diff_file (void)
             ? O_NOATIME
             : 0);
 
-         diff_handle = open (file_name, O_RDONLY | O_BINARY | atime_flag);
+         diff_handle = openat (chdir_fd, file_name,
+                               (O_RDONLY | O_BINARY | O_CLOEXEC | O_NOCTTY
+                                | O_NONBLOCK | atime_flag));
 
          if (diff_handle < 0)
            {
@@ -242,10 +243,10 @@ diff_file (void)
 
              if (atime_preserve_option == replace_atime_preserve)
                {
-                 struct timespec ts[2];
-                 ts[0] = get_stat_atime (&stat_data);
-                 ts[1] = get_stat_mtime (&stat_data);
-                 if (set_file_atime (diff_handle, file_name, ts) != 0)
+                 struct timespec atime = get_stat_atime (&stat_data);
+                 if (set_file_atime (diff_handle, chdir_fd, file_name,
+                                     atime, 0)
+                     != 0)
                    utime_error (file_name);
                }
 
@@ -278,7 +279,8 @@ diff_symlink (void)
   size_t len = strlen (current_stat_info.link_name);
   char *linkbuf = alloca (len + 1);
 
-  int status = readlink (current_stat_info.file_name, linkbuf, len + 1);
+  int status = readlinkat (chdir_fd, current_stat_info.file_name,
+                          linkbuf, len + 1);
 
   if (status < 0)
     {
@@ -332,7 +334,7 @@ static int
 dumpdir_cmp (const char *a, const char *b)
 {
   size_t len;
-  
+
   while (*a)
     switch (*a)
       {
@@ -346,7 +348,7 @@ dumpdir_cmp (const char *a, const char *b)
        a += len;
        b += len;
        break;
-       
+
       case 'D':
        if (strcmp(a, b))
          return 1;
@@ -354,7 +356,7 @@ dumpdir_cmp (const char *a, const char *b)
        a += len;
        b += len;
        break;
-       
+
       case 'R':
       case 'T':
       case 'X':
@@ -366,11 +368,11 @@ dumpdir_cmp (const char *a, const char *b)
 static void
 diff_dumpdir (void)
 {
-  char *dumpdir_buffer;
+  const char *dumpdir_buffer;
   dev_t dev = 0;
-  struct stat stat;
+  struct stat stat_data;
 
-  if (deref_stat (true, current_stat_info.file_name, &stat))
+  if (deref_stat (true, current_stat_info.file_name, &stat_data))
     {
       if (errno == ENOENT)
        stat_warn (current_stat_info.file_name);
@@ -378,9 +380,9 @@ diff_dumpdir (void)
        stat_error (current_stat_info.file_name);
     }
   else
-    dev = stat.st_dev;
+    dev = stat_data.st_dev;
 
-  dumpdir_buffer = get_directory_contents (current_stat_info.file_name, dev);
+  dumpdir_buffer = directory_contents (scan_directory (&current_stat_info));
 
   if (dumpdir_buffer)
     {
@@ -397,6 +399,10 @@ diff_multivol (void)
   struct stat stat_data;
   int fd, status;
   off_t offset;
+  int atime_flag =
+    (atime_preserve_option == system_atime_preserve
+     ? O_NOATIME
+     : 0);
 
   if (current_stat_info.had_trailing_slash)
     {
@@ -422,7 +428,10 @@ diff_multivol (void)
       return;
     }
 
-  fd = open (current_stat_info.file_name, O_RDONLY | O_BINARY);
+
+  fd = openat (chdir_fd, current_stat_info.file_name,
+              (O_RDONLY | O_BINARY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK
+               | atime_flag));
 
   if (fd < 0)
     {
@@ -452,7 +461,6 @@ diff_archive (void)
 {
 
   set_next_block_after (current_header);
-  decode_header (current_header, &current_stat_info, &current_format, 1);
 
   /* Print the block from current_header and current_stat_info.  */
 
@@ -460,7 +468,7 @@ diff_archive (void)
     {
       if (now_verifying)
        fprintf (stdlis, _("Verify "));
-      print_header (&current_stat_info, -1);
+      print_header (&current_stat_info, current_header, -1);
     }
 
   switch (current_header->header.typeflag)
@@ -578,7 +586,9 @@ verify_volume (void)
   flush_read ();
   while (1)
     {
-      enum read_header status = read_header (false);
+      enum read_header status = read_header (&current_header,
+                                             &current_stat_info,
+                                             read_header_auto);
 
       if (status == HEADER_FAILURE)
        {
@@ -588,7 +598,8 @@ verify_volume (void)
            {
              counter++;
              set_next_block_after (current_header);
-             status = read_header (false);
+             status = read_header (&current_header, &current_stat_info,
+                                   read_header_auto);
            }
          while (status == HEADER_FAILURE);
 
@@ -597,8 +608,24 @@ verify_volume (void)
                            "VERIFY FAILURE: %d invalid headers detected",
                            counter), counter));
        }
-      if (status == HEADER_ZERO_BLOCK || status == HEADER_END_OF_FILE)
+      if (status == HEADER_END_OF_FILE)
        break;
+      if (status == HEADER_ZERO_BLOCK)
+       {
+         set_next_block_after (current_header);
+          if (!ignore_zeros_option)
+            {
+             char buf[UINTMAX_STRSIZE_BOUND];
+
+             status = read_header (&current_header, &current_stat_info,
+                                   read_header_auto);
+             if (status == HEADER_ZERO_BLOCK)
+               break;
+             WARNOPT (WARN_ALONE_ZERO_BLOCK,
+                      (0, 0, _("A lone zero block at %s"),
+                       STRINGIFY_BIGINT (current_block_ordinal (), buf)));
+            }
+       }
 
       diff_archive ();
       tar_stat_destroy (&current_stat_info);