| 1 | /* Heap management routines for GNU Emacs on the Microsoft W32 API. |
| 2 | Copyright (C) 1994 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GNU Emacs. |
| 5 | |
| 6 | GNU Emacs is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GNU Emacs is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GNU Emacs; see the file COPYING. If not, write to |
| 18 | the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. |
| 20 | |
| 21 | Geoff Voelker (voelker@cs.washington.edu) 7-29-94 |
| 22 | */ |
| 23 | |
| 24 | #ifdef HAVE_CONFIG_H |
| 25 | #include <config.h> |
| 26 | #endif |
| 27 | |
| 28 | #include <stdlib.h> |
| 29 | #include <stdio.h> |
| 30 | |
| 31 | #include "w32heap.h" |
| 32 | #include "lisp.h" /* for VALMASK */ |
| 33 | |
| 34 | #undef RVA_TO_PTR |
| 35 | #define RVA_TO_PTR(rva) ((unsigned char *)((DWORD)(rva) + (DWORD)GetModuleHandle (NULL))) |
| 36 | |
| 37 | /* This gives us the page size and the size of the allocation unit on NT. */ |
| 38 | SYSTEM_INFO sysinfo_cache; |
| 39 | |
| 40 | /* This gives us version, build, and platform identification. */ |
| 41 | OSVERSIONINFO osinfo_cache; |
| 42 | |
| 43 | unsigned long syspage_mask = 0; |
| 44 | |
| 45 | /* These are defined to get Emacs to compile, but are not used. */ |
| 46 | int edata; |
| 47 | int etext; |
| 48 | |
| 49 | /* The major and minor versions of NT. */ |
| 50 | int w32_major_version; |
| 51 | int w32_minor_version; |
| 52 | int w32_build_number; |
| 53 | |
| 54 | /* Distinguish between Windows NT and Windows 95. */ |
| 55 | int os_subtype; |
| 56 | |
| 57 | /* Cache information describing the NT system for later use. */ |
| 58 | void |
| 59 | cache_system_info (void) |
| 60 | { |
| 61 | union |
| 62 | { |
| 63 | struct info |
| 64 | { |
| 65 | char major; |
| 66 | char minor; |
| 67 | short platform; |
| 68 | } info; |
| 69 | DWORD data; |
| 70 | } version; |
| 71 | |
| 72 | /* Cache the version of the operating system. */ |
| 73 | version.data = GetVersion (); |
| 74 | w32_major_version = version.info.major; |
| 75 | w32_minor_version = version.info.minor; |
| 76 | |
| 77 | if (version.info.platform & 0x8000) |
| 78 | os_subtype = OS_WIN95; |
| 79 | else |
| 80 | os_subtype = OS_NT; |
| 81 | |
| 82 | /* Cache page size, allocation unit, processor type, etc. */ |
| 83 | GetSystemInfo (&sysinfo_cache); |
| 84 | syspage_mask = sysinfo_cache.dwPageSize - 1; |
| 85 | |
| 86 | /* Cache os info. */ |
| 87 | osinfo_cache.dwOSVersionInfoSize = sizeof (OSVERSIONINFO); |
| 88 | GetVersionEx (&osinfo_cache); |
| 89 | |
| 90 | w32_build_number = osinfo_cache.dwBuildNumber; |
| 91 | if (os_subtype == OS_WIN95) |
| 92 | w32_build_number &= 0xffff; |
| 93 | } |
| 94 | |
| 95 | /* Emulate getpagesize. */ |
| 96 | int |
| 97 | getpagesize (void) |
| 98 | { |
| 99 | return sysinfo_cache.dwPageSize; |
| 100 | } |
| 101 | |
| 102 | /* Info for managing our preload heap, which is essentially a fixed size |
| 103 | data area in the executable. */ |
| 104 | PIMAGE_SECTION_HEADER preload_heap_section; |
| 105 | |
| 106 | /* Info for keeping track of our heap. */ |
| 107 | unsigned char *data_region_base = NULL; |
| 108 | unsigned char *data_region_end = NULL; |
| 109 | unsigned char *real_data_region_end = NULL; |
| 110 | unsigned long reserved_heap_size = 0; |
| 111 | |
| 112 | /* The start of the data segment. */ |
| 113 | unsigned char * |
| 114 | get_data_start (void) |
| 115 | { |
| 116 | return data_region_base; |
| 117 | } |
| 118 | |
| 119 | /* The end of the data segment. */ |
| 120 | unsigned char * |
| 121 | get_data_end (void) |
| 122 | { |
| 123 | return data_region_end; |
| 124 | } |
| 125 | |
| 126 | static char * |
| 127 | allocate_heap (void) |
| 128 | { |
| 129 | /* Try to get as much as possible of the address range from the end of |
| 130 | the preload heap section up to the usable address limit. Since GNU |
| 131 | malloc can handle gaps in the memory it gets from sbrk, we can |
| 132 | simply set the sbrk pointer to the base of the new heap region. */ |
| 133 | unsigned long base = |
| 134 | ROUND_UP ((RVA_TO_PTR (preload_heap_section->VirtualAddress) |
| 135 | + preload_heap_section->Misc.VirtualSize), |
| 136 | get_allocation_unit ()); |
| 137 | unsigned long end = 1 << VALBITS; /* 256MB */ |
| 138 | void *ptr = NULL; |
| 139 | |
| 140 | while (!ptr && (base < end)) |
| 141 | { |
| 142 | reserved_heap_size = end - base; |
| 143 | ptr = VirtualAlloc ((void *) base, |
| 144 | get_reserved_heap_size (), |
| 145 | MEM_RESERVE, |
| 146 | PAGE_NOACCESS); |
| 147 | base += 0x00100000; /* 1MB increment */ |
| 148 | } |
| 149 | |
| 150 | return ptr; |
| 151 | } |
| 152 | |
| 153 | |
| 154 | /* Emulate Unix sbrk. */ |
| 155 | void * |
| 156 | sbrk (unsigned long increment) |
| 157 | { |
| 158 | void *result; |
| 159 | long size = (long) increment; |
| 160 | |
| 161 | result = data_region_end; |
| 162 | |
| 163 | /* If size is negative, shrink the heap by decommitting pages. */ |
| 164 | if (size < 0) |
| 165 | { |
| 166 | int new_size; |
| 167 | unsigned char *new_data_region_end; |
| 168 | |
| 169 | size = -size; |
| 170 | |
| 171 | /* Sanity checks. */ |
| 172 | if ((data_region_end - size) < data_region_base) |
| 173 | return NULL; |
| 174 | |
| 175 | /* We can only decommit full pages, so allow for |
| 176 | partial deallocation [cga]. */ |
| 177 | new_data_region_end = (data_region_end - size); |
| 178 | new_data_region_end = (unsigned char *) |
| 179 | ((long) (new_data_region_end + syspage_mask) & ~syspage_mask); |
| 180 | new_size = real_data_region_end - new_data_region_end; |
| 181 | real_data_region_end = new_data_region_end; |
| 182 | if (new_size > 0) |
| 183 | { |
| 184 | /* Decommit size bytes from the end of the heap. */ |
| 185 | if (using_dynamic_heap |
| 186 | && !VirtualFree (real_data_region_end, new_size, MEM_DECOMMIT)) |
| 187 | return NULL; |
| 188 | } |
| 189 | |
| 190 | data_region_end -= size; |
| 191 | } |
| 192 | /* If size is positive, grow the heap by committing reserved pages. */ |
| 193 | else if (size > 0) |
| 194 | { |
| 195 | /* Sanity checks. */ |
| 196 | if ((data_region_end + size) > |
| 197 | (data_region_base + get_reserved_heap_size ())) |
| 198 | return NULL; |
| 199 | |
| 200 | /* Commit more of our heap. */ |
| 201 | if (using_dynamic_heap |
| 202 | && VirtualAlloc (data_region_end, size, MEM_COMMIT, |
| 203 | PAGE_READWRITE) == NULL) |
| 204 | return NULL; |
| 205 | data_region_end += size; |
| 206 | |
| 207 | /* We really only commit full pages, so record where |
| 208 | the real end of committed memory is [cga]. */ |
| 209 | real_data_region_end = (unsigned char *) |
| 210 | ((long) (data_region_end + syspage_mask) & ~syspage_mask); |
| 211 | } |
| 212 | |
| 213 | return result; |
| 214 | } |
| 215 | |
| 216 | /* Initialize the internal heap variables used by sbrk. When running in |
| 217 | preload phase (ie. in the undumped executable), we rely entirely on a |
| 218 | fixed size heap section included in the .exe itself; this is |
| 219 | preserved during dumping, and truncated to the size actually used. |
| 220 | |
| 221 | When running in the dumped executable, we reserve as much as possible |
| 222 | of the address range that is addressable by Lisp object pointers, to |
| 223 | supplement what is left of the preload heap. Although we cannot rely |
| 224 | on the dynamically allocated arena being contiguous with the static |
| 225 | heap area, it is not a problem because sbrk can pretend that the gap |
| 226 | was allocated by something else; GNU malloc detects when there is a |
| 227 | jump in the sbrk values, and starts a new heap block. */ |
| 228 | void |
| 229 | init_heap () |
| 230 | { |
| 231 | PIMAGE_DOS_HEADER dos_header; |
| 232 | PIMAGE_NT_HEADERS nt_header; |
| 233 | |
| 234 | dos_header = (PIMAGE_DOS_HEADER) RVA_TO_PTR (0); |
| 235 | nt_header = (PIMAGE_NT_HEADERS) (((unsigned long) dos_header) + |
| 236 | dos_header->e_lfanew); |
| 237 | preload_heap_section = find_section ("EMHEAP", nt_header); |
| 238 | |
| 239 | if (using_dynamic_heap) |
| 240 | { |
| 241 | data_region_base = allocate_heap (); |
| 242 | if (!data_region_base) |
| 243 | { |
| 244 | printf ("Error: Could not reserve dynamic heap area.\n"); |
| 245 | exit (1); |
| 246 | } |
| 247 | |
| 248 | #if defined (NO_UNION_TYPE) && !defined (USE_LSB_TAG) |
| 249 | /* Ensure that the addresses don't use the upper tag bits since |
| 250 | the Lisp type goes there. */ |
| 251 | if (((unsigned long) data_region_base & ~VALMASK) != 0) |
| 252 | { |
| 253 | printf ("Error: The heap was allocated in upper memory.\n"); |
| 254 | exit (1); |
| 255 | } |
| 256 | #endif |
| 257 | data_region_end = data_region_base; |
| 258 | real_data_region_end = data_region_end; |
| 259 | } |
| 260 | else |
| 261 | { |
| 262 | data_region_base = RVA_TO_PTR (preload_heap_section->VirtualAddress); |
| 263 | data_region_end = data_region_base; |
| 264 | real_data_region_end = data_region_end; |
| 265 | reserved_heap_size = preload_heap_section->Misc.VirtualSize; |
| 266 | } |
| 267 | |
| 268 | /* Update system version information to match current system. */ |
| 269 | cache_system_info (); |
| 270 | } |
| 271 | |
| 272 | /* Round the heap up to the given alignment. */ |
| 273 | void |
| 274 | round_heap (unsigned long align) |
| 275 | { |
| 276 | unsigned long needs_to_be; |
| 277 | unsigned long need_to_alloc; |
| 278 | |
| 279 | needs_to_be = (unsigned long) ROUND_UP (get_heap_end (), align); |
| 280 | need_to_alloc = needs_to_be - (unsigned long) get_heap_end (); |
| 281 | |
| 282 | if (need_to_alloc) |
| 283 | sbrk (need_to_alloc); |
| 284 | } |
| 285 | |
| 286 | #if (_MSC_VER >= 1000 && _MSC_VER < 1300 && !defined(USE_CRT_DLL)) |
| 287 | |
| 288 | /* MSVC 4.2 invokes these functions from mainCRTStartup to initialize |
| 289 | a heap via HeapCreate. They are normally defined by the runtime, |
| 290 | but we override them here so that the unnecessary HeapCreate call |
| 291 | is not performed. */ |
| 292 | |
| 293 | int __cdecl |
| 294 | _heap_init (void) |
| 295 | { |
| 296 | /* Stepping through the assembly indicates that mainCRTStartup is |
| 297 | expecting a nonzero success return value. */ |
| 298 | return 1; |
| 299 | } |
| 300 | |
| 301 | void __cdecl |
| 302 | _heap_term (void) |
| 303 | { |
| 304 | return; |
| 305 | } |
| 306 | |
| 307 | #endif |
| 308 | |
| 309 | /* arch-tag: 9a6a9860-040d-422d-8905-450dd535cd9c |
| 310 | (do not change this comment) */ |