(Syntax Table Functions):
[emacs.git] / src / sheap.c
blob635c3dc0144ee8ec6cc742a4ab364a6f71d69113
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)
11 any later version.
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. */
23 #include <config.h>
24 #include <stdio.h>
25 #include "lisp.h"
27 #include <unistd.h>
29 #ifdef HAVE_X_WINDOWS
30 #define STATIC_HEAP_SIZE (7 * 1024 * 1024)
31 #else
32 #define STATIC_HEAP_SIZE (7 * 1024 * 1024)
33 #endif
35 int debug_sheap = 0;
37 #define BLOCKSIZE 4096
39 char bss_sbrk_buffer[STATIC_HEAP_SIZE];
40 char *bss_sbrk_ptr;
41 int bss_sbrk_did_unexec;
43 void *
44 bss_sbrk (ptrdiff_t request_size)
46 if (!bss_sbrk_ptr)
48 bss_sbrk_ptr = bss_sbrk_buffer;
49 #ifdef CYGWIN
50 sbrk (BLOCKSIZE); /* force space for fork to work */
51 #endif
54 if (!(int) request_size)
56 return (bss_sbrk_ptr);
58 else if (bss_sbrk_ptr + (int) request_size < bss_sbrk_buffer)
60 printf
61 ("attempt to free too much: avail %d used %d failed request %d\n",
62 STATIC_HEAP_SIZE, bss_sbrk_ptr - bss_sbrk_buffer,
63 (int) request_size);
64 exit (-1);
65 return 0;
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",
71 STATIC_HEAP_SIZE,
72 bss_sbrk_ptr - bss_sbrk_buffer, (int) request_size);
73 exit (-1);
74 return 0;
76 else if ((int) request_size < 0)
78 bss_sbrk_ptr += (int) request_size;
79 if (debug_sheap)
80 printf ("freed size %d\n", request_size);
81 return bss_sbrk_ptr;
83 else
85 char *ret = bss_sbrk_ptr;
86 if (debug_sheap)
87 printf ("allocated 0x%08x size %d\n", ret, request_size);
88 bss_sbrk_ptr += (int) request_size;
89 return ret;
93 void
94 report_sheap_usage (int die_if_pure_storage_exceeded)
96 char buf[200];
97 sprintf (buf, "Static heap usage: %d of %d bytes",
98 bss_sbrk_ptr - bss_sbrk_buffer, STATIC_HEAP_SIZE);
99 message ("%s", buf);
102 /* arch-tag: 1bc386e8-71c2-4da4-b8b5-c1674a9cf926
103 (do not change this comment) */