1 /* simulate sbrk() with an array in .bss, for unexec() support for Cygwin;
2 complete rewrite of xemacs Cygwin unexec() code
4 Copyright (C) 2004, 2005 Free Software Foundation, Inc.
6 This file is part of GNU Emacs.
8 GNU Emacs is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GNU Emacs is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU Emacs; see the file COPYING. If not, write to
20 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
30 #define STATIC_HEAP_SIZE (7 * 1024 * 1024)
32 #define STATIC_HEAP_SIZE (7 * 1024 * 1024)
37 #define BLOCKSIZE 4096
39 char bss_sbrk_buffer
[STATIC_HEAP_SIZE
];
41 int bss_sbrk_did_unexec
;
44 bss_sbrk (ptrdiff_t request_size
)
48 bss_sbrk_ptr
= bss_sbrk_buffer
;
50 sbrk (BLOCKSIZE
); /* force space for fork to work */
54 if (!(int) request_size
)
56 return (bss_sbrk_ptr
);
58 else if (bss_sbrk_ptr
+ (int) request_size
< bss_sbrk_buffer
)
61 ("attempt to free too much: avail %d used %d failed request %d\n",
62 STATIC_HEAP_SIZE
, bss_sbrk_ptr
- bss_sbrk_buffer
,
67 else if (bss_sbrk_ptr
+ (int) request_size
>
68 bss_sbrk_buffer
+ STATIC_HEAP_SIZE
)
70 printf ("static heap exhausted: avail %d used %d failed request %d\n",
72 bss_sbrk_ptr
- bss_sbrk_buffer
, (int) request_size
);
76 else if ((int) request_size
< 0)
78 bss_sbrk_ptr
+= (int) request_size
;
80 printf ("freed size %d\n", request_size
);
85 char *ret
= bss_sbrk_ptr
;
87 printf ("allocated 0x%08x size %d\n", ret
, request_size
);
88 bss_sbrk_ptr
+= (int) request_size
;
94 report_sheap_usage (int die_if_pure_storage_exceeded
)
97 sprintf (buf
, "Static heap usage: %d of %d bytes",
98 bss_sbrk_ptr
- bss_sbrk_buffer
, STATIC_HEAP_SIZE
);
102 /* arch-tag: 1bc386e8-71c2-4da4-b8b5-c1674a9cf926
103 (do not change this comment) */