update copyright for 2014 year bump

[gnulib.git] / lib / renameat.c

diff --git a/lib/renameat.c b/lib/renameat.c
index 244ee38..8d26971 100644 (file)
--- a/lib/renameat.c
+++ b/lib/renameat.c
@@ -1,5 +1,5 @@
 /* Rename a file relative to open directories.
-   Copyright (C) 2009 Free Software Foundation, Inc.
+   Copyright (C) 2009-2014 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
@@ -20,7 +20,127 @@
 
 #include <stdio.h>
 
-#include "openat-priv.h"
+#if HAVE_RENAMEAT
+
+# include <errno.h>
+# include <stdbool.h>
+# include <stdlib.h>
+# include <string.h>
+# include <sys/stat.h>
+
+# include "dirname.h"
+# include "openat.h"
+
+# undef renameat
+
+/* renameat does not honor trailing / on Solaris 10.  Solve it in a
+   similar manner to rename.  No need to worry about bugs not present
+   on Solaris, since all other systems either lack renameat or honor
+   trailing slash correctly.  */
+
+int
+rpl_renameat (int fd1, char const *src, int fd2, char const *dst)
+{
+  size_t src_len = strlen (src);
+  size_t dst_len = strlen (dst);
+  char *src_temp = (char *) src;
+  char *dst_temp = (char *) dst;
+  bool src_slash;
+  bool dst_slash;
+  int ret_val = -1;
+  int rename_errno = ENOTDIR;
+  struct stat src_st;
+  struct stat dst_st;
+
+  /* Let strace see any ENOENT failure.  */
+  if (!src_len || !dst_len)
+    return renameat (fd1, src, fd2, dst);
+
+  src_slash = src[src_len - 1] == '/';
+  dst_slash = dst[dst_len - 1] == '/';
+  if (!src_slash && !dst_slash)
+    return renameat (fd1, src, fd2, dst);
+
+  /* Presence of a trailing slash requires directory semantics.  If
+     the source does not exist, or if the destination cannot be turned
+     into a directory, give up now.  Otherwise, strip trailing slashes
+     before calling rename.  */
+  if (lstatat (fd1, src, &src_st))
+    return -1;
+  if (lstatat (fd2, dst, &dst_st))
+    {
+      if (errno != ENOENT || !S_ISDIR (src_st.st_mode))
+        return -1;
+    }
+  else if (!S_ISDIR (dst_st.st_mode))
+    {
+      errno = ENOTDIR;
+      return -1;
+    }
+  else if (!S_ISDIR (src_st.st_mode))
+    {
+      errno = EISDIR;
+      return -1;
+    }
+
+# if RENAME_TRAILING_SLASH_SOURCE_BUG
+  /* See the lengthy comment in rename.c why Solaris 9 is forced to
+     GNU behavior, while Solaris 10 is left with POSIX behavior,
+     regarding symlinks with trailing slash.  */
+  if (src_slash)
+    {
+      src_temp = strdup (src);
+      if (!src_temp)
+        {
+          /* Rather than rely on strdup-posix, we set errno ourselves.  */
+          rename_errno = ENOMEM;
+          goto out;
+        }
+      strip_trailing_slashes (src_temp);
+      if (lstatat (fd1, src_temp, &src_st))
+        {
+          rename_errno = errno;
+          goto out;
+        }
+      if (S_ISLNK (src_st.st_mode))
+        goto out;
+    }
+  if (dst_slash)
+    {
+      dst_temp = strdup (dst);
+      if (!dst_temp)
+        {
+          rename_errno = ENOMEM;
+          goto out;
+        }
+      strip_trailing_slashes (dst_temp);
+      if (lstatat (fd2, dst_temp, &dst_st))
+        {
+          if (errno != ENOENT)
+            {
+              rename_errno = errno;
+              goto out;
+            }
+        }
+      else if (S_ISLNK (dst_st.st_mode))
+        goto out;
+    }
+# endif /* RENAME_TRAILING_SLASH_SOURCE_BUG */
+
+  ret_val = renameat (fd1, src_temp, fd2, dst_temp);
+  rename_errno = errno;
+ out:
+  if (src_temp != src)
+    free (src_temp);
+  if (dst_temp != dst)
+    free (dst_temp);
+  errno = rename_errno;
+  return ret_val;
+}
+
+#else /* !HAVE_RENAMEAT */
+
+# include "openat-priv.h"
 
 /* Rename FILE1, in the directory open on descriptor FD1, to FILE2, in
    the directory open on descriptor FD2.  If possible, do it without
@@ -33,3 +153,5 @@ renameat (int fd1, char const *file1, int fd2, char const *file2)
 {
   return at_func2 (fd1, file1, fd2, file2, rename);
 }
+
+#endif /* !HAVE_RENAMEAT */