* lib/canonicalize.h: (canonicalize_mode_t, CAN_EXISTING):

[gnulib.git] / lib / pagealign_alloc.c

diff --git a/lib/pagealign_alloc.c b/lib/pagealign_alloc.c
index 6e07a3a..521bde5 100644 (file)
--- a/lib/pagealign_alloc.c
+++ b/lib/pagealign_alloc.c
@@ -1,6 +1,6 @@
 /* Memory allocation aligned to system page boundaries.
 
-   Copyright (C) 2005 Free Software Foundation, Inc.
+   Copyright (C) 2005, 2006 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
@@ -14,27 +14,20 @@
 
    You should have received a copy of the GNU General Public
    License along with this program; if not, write to the Free Software
-   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
    USA.  */
 
 /* Written by Derek R. Price <derek@ximbiot.com>.  */
 
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
 
 #include "pagealign_alloc.h"
 
 #include <errno.h>
 #include <stdlib.h>
 
-#if HAVE_FCNTL_H
-# include <fcntl.h>
-#endif
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <fcntl.h>
+#include <unistd.h>
 
 #if HAVE_MMAP
 # include <sys/mman.h>
@@ -48,6 +41,17 @@
 
 #define _(str) gettext (str)
 
+#if HAVE_MMAP
+/* Define MAP_FILE when it isn't otherwise.  */
+# ifndef MAP_FILE
+#  define MAP_FILE 0
+# endif
+/* Define MAP_FAILED for old systems which neglect to.  */
+# ifndef MAP_FAILED
+#  define MAP_FAILED ((void *)-1)
+# endif
+#endif
+
 
 #if HAVE_MMAP || ! HAVE_POSIX_MEMALIGN
 
@@ -119,15 +123,14 @@ pagealign_alloc (size_t size)
 {
   void *ret;
 #if HAVE_MMAP
-  int flags;
 # ifdef HAVE_MAP_ANONYMOUS
   const int fd = -1;
-  flags = MAP_ANONYMOUS | MAP_PRIVATE;
+  const int flags = MAP_ANONYMOUS | MAP_PRIVATE;
 # else /* !HAVE_MAP_ANONYMOUS */
   static int fd = -1;  /* Only open /dev/zero once in order to avoid limiting
                          the amount of memory we may allocate based on the
                          number of open file descriptors.  */
-  flags = MAP_FILE | MAP_PRIVATE;
+  const int flags = MAP_FILE | MAP_PRIVATE;
   if (fd == -1)
     {
       fd = open ("/dev/zero", O_RDONLY, 0666);
@@ -136,18 +139,26 @@ pagealign_alloc (size_t size)
     }
 # endif /* HAVE_MAP_ANONYMOUS */
   ret = mmap (NULL, size, PROT_READ | PROT_WRITE, flags, fd, 0);
-  if (!ret)
+  if (ret == MAP_FAILED)
     return NULL;
   new_memnode (ret, size);
 #elif HAVE_POSIX_MEMALIGN
   int status = posix_memalign (&ret, getpagesize (), size);
   if (status)
-    return NULL;
+    {
+      errno = status;
+      return NULL;
+    }
 #else /* !HAVE_MMAP && !HAVE_POSIX_MEMALIGN */
   size_t pagesize = getpagesize ();
   void *unaligned_ptr = malloc (size + pagesize - 1);
   if (unaligned_ptr == NULL)
-    return NULL;
+    {
+      /* Set errno.  We don't know whether malloc already set errno: some
+        implementations of malloc do, some don't.  */
+      errno = ENOMEM;
+      return NULL;
+    }
   ret = (char *) unaligned_ptr
         + ((- (unsigned long) unaligned_ptr) & (pagesize - 1));
   new_memnode (ret, unaligned_ptr);
@@ -172,7 +183,8 @@ void
 pagealign_free (void *aligned_ptr)
 {
 #if HAVE_MMAP
-  munmap (aligned_ptr, get_memnode (aligned_ptr));
+  if (munmap (aligned_ptr, get_memnode (aligned_ptr)) < 0)
+    error (EXIT_FAILURE, errno, "Failed to unmap memory");
 #elif HAVE_POSIX_MEMALIGN
   free (aligned_ptr);
 #else