1169689Skan/* Cygwin host-specific hook definitions.
2169689Skan Copyright (C) 2004 Free Software Foundation, Inc.
3169689Skan
4169689Skan This file is part of GCC.
5169689Skan
6169689Skan GCC is free software; you can redistribute it and/or modify it
7169689Skan under the terms of the GNU General Public License as published
8169689Skan by the Free Software Foundation; either version 2, or (at your
9169689Skan option) any later version.
10169689Skan
11169689Skan GCC is distributed in the hope that it will be useful, but WITHOUT
12169689Skan ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13169689Skan or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14169689Skan License for more details.
15169689Skan
16169689Skan You should have received a copy of the GNU General Public License
17169689Skan along with GCC; see the file COPYING. If not, write to the
18169689Skan Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
19169689Skan MA 02110-1301, USA. */
20169689Skan
21169689Skan#include "config.h"
22169689Skan#include "system.h"
23169689Skan#include "coretypes.h"
24169689Skan#include <sys/mman.h>
25169689Skan#include "hosthooks.h"
26169689Skan#include "hosthooks-def.h"
27169689Skan#include "toplev.h"
28169689Skan#include "diagnostic.h"
29169689Skan
30169689Skanstatic void * cygwin_gt_pch_get_address (size_t, int fd);
31169689Skanstatic size_t cygwin_gt_pch_alloc_granularity (void);
32169689Skan
33169689Skan#undef HOST_HOOKS_GT_PCH_GET_ADDRESS
34169689Skan#define HOST_HOOKS_GT_PCH_GET_ADDRESS cygwin_gt_pch_get_address
35169689Skan#undef HOST_HOOKS_GT_PCH_ALLOC_GRANULARITY
36169689Skan#define HOST_HOOKS_GT_PCH_ALLOC_GRANULARITY cygwin_gt_pch_alloc_granularity
37169689Skan
38169689Skan/* Granularity for reserving address space.  */
39169689Skanstatic const size_t va_granularity = 0x10000;
40169689Skan
41169689Skan/*  Return the alignment required for allocating virtual memory. */
42169689Skanstatic size_t
43169689Skancygwin_gt_pch_alloc_granularity (void)
44169689Skan{
45169689Skan  return va_granularity;
46169689Skan}
47169689Skan
48169689Skan/* Identify an address that's likely to be free in a subsequent invocation
49169689Skan   of the compiler.  The area should be able to hold SIZE bytes.  FD is an
50169689Skan   open file descriptor if the host would like to probe with mmap.  */
51169689Skanstatic void *
52169689Skancygwin_gt_pch_get_address (size_t sz, int fd)
53169689Skan{
54169689Skan  void *base;
55169689Skan  off_t p = lseek(fd, 0, SEEK_CUR);
56169689Skan
57169689Skan  if (p == (off_t) -1)
58169689Skan    fatal_error ("can't get position in PCH file: %m");
59169689Skan
60169689Skan   /* Cygwin requires that the underlying file be at least
61169689Skan      as large as the requested mapping.  */
62169689Skan  if ((size_t) p < sz)
63169689Skan  {
64169689Skan    if ( ftruncate (fd, sz) == -1 )
65169689Skan      fatal_error ("can't extend PCH file: %m");
66169689Skan  }
67169689Skan
68169689Skan  base = mmap (NULL, sz, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
69169689Skan
70169689Skan  if (base == MAP_FAILED)
71169689Skan    base = NULL;
72169689Skan  else
73169689Skan    munmap (base, sz);
74169689Skan
75169689Skan  if (lseek (fd, p, SEEK_SET) == (off_t) -1 )
76169689Skan    fatal_error ("can't set position in PCH file: %m");
77169689Skan
78169689Skan  return base;
79169689Skan}
80169689Skan
81169689Skanconst struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER;
82