/* Linux host-specific hook definitions.
- Copyright (C) 2004 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2007, 2008, 2010 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GCC is distributed in the hope that it will be useful, but WITHOUT
License for more details.
You should have received a copy of the GNU General Public License
- along with GCC; see the file COPYING. If not, write to the
- Free Software Foundation, 59 Temple Place - Suite 330, Boston,
- MA 02111-1307, USA. */
+ along with GCC; see the file COPYING3. If not see
+ <http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
-#include <sys/mman.h>
#include "hosthooks.h"
#include "hosthooks-def.h"
#undef HOST_HOOKS_GT_PCH_GET_ADDRESS
#define HOST_HOOKS_GT_PCH_GET_ADDRESS linux_gt_pch_get_address
+#undef HOST_HOOKS_GT_PCH_USE_ADDRESS
+#define HOST_HOOKS_GT_PCH_USE_ADDRESS linux_gt_pch_use_address
+
/* For various ports, try to guess a fixed spot in the vm space
that's probably free. */
#if defined(__alpha)
# define TRY_EMPTY_VM_SPACE 0x8000000000
#elif defined(__s390__)
# define TRY_EMPTY_VM_SPACE 0x60000000
-#elif defined(__hppa__)
-# define TRY_EMPTY_VM_SPACE 0xa0000000
#elif defined(__sparc__) && defined(__LP64__)
# define TRY_EMPTY_VM_SPACE 0x8000000000
#elif defined(__sparc__)
# define TRY_EMPTY_VM_SPACE 0x60000000
+#elif defined(__mc68000__)
+# define TRY_EMPTY_VM_SPACE 0x40000000
#else
# define TRY_EMPTY_VM_SPACE 0
#endif
if (TRY_EMPTY_VM_SPACE && addr == (void *) TRY_EMPTY_VM_SPACE)
return addr;
- /* If we didn't, then we need to look to see if randomization is on. */
- f = fopen ("/proc/sys/kernel/exec-shield-randomize", "r");
+ /* If we didn't, then we need to look to see if virtual address
+ randomization is on. That is recorded in
+ kernel.randomize_va_space. An older implementation used
+ kernel.exec-shield-randomize. */
+ f = fopen ("/proc/sys/kernel/randomize_va_space", "r");
+ if (f == NULL)
+ f = fopen ("/proc/sys/kernel/exec-shield-randomize", "r");
randomize_on = false;
if (f != NULL)
{
return addr;
}
+/* Map SIZE bytes of FD+OFFSET at BASE. Return 1 if we succeeded at
+ mapping the data at BASE, -1 if we couldn't.
+
+ It's not possibly to reliably mmap a file using MAP_PRIVATE to
+ a specific START address on either hpux or linux. First we see
+ if mmap with MAP_PRIVATE works. If it does, we are off to the
+ races. If it doesn't, we try an anonymous private mmap since the
+ kernel is more likely to honor the BASE address in anonymous maps.
+ We then copy the data to the anonymous private map. This assumes
+ of course that we don't need to change the data in the PCH file
+ after it is created.
+
+ This approach obviously causes a performance penalty but there is
+ little else we can do given the current PCH implementation. */
+
+static int
+linux_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
+{
+ void *addr;
+
+ /* We're called with size == 0 if we're not planning to load a PCH
+ file at all. This allows the hook to free any static space that
+ we might have allocated at link time. */
+ if (size == 0)
+ return -1;
+
+ /* Try to map the file with MAP_PRIVATE. */
+ addr = mmap (base, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, offset);
+
+ if (addr == base)
+ return 1;
+
+ if (addr != (void *) MAP_FAILED)
+ munmap (addr, size);
+
+ /* Try to make an anonymous private mmap at the desired location. */
+ addr = mmap (base, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (addr != base)
+ {
+ if (addr != (void *) MAP_FAILED)
+ munmap (addr, size);
+ return -1;
+ }
+
+ if (lseek (fd, offset, SEEK_SET) == (off_t)-1)
+ return -1;
+
+ while (size)
+ {
+ ssize_t nbytes;
+
+ nbytes = read (fd, base, MIN (size, SSIZE_MAX));
+ if (nbytes <= 0)
+ return -1;
+ base = (char *) base + nbytes;
+ size -= nbytes;
+ }
+
+ return 1;
+}
+
\f
const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;
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