2 * winmisc.c: miscellaneous Windows-specific things
9 OSVERSIONINFO osVersion;
11 char *platform_get_x_display(void) {
12 /* We may as well check for DISPLAY in case it's useful. */
13 return dupstr(getenv("DISPLAY"));
16 Filename filename_from_str(const char *str)
19 strncpy(ret.path, str, sizeof(ret.path));
20 ret.path[sizeof(ret.path)-1] = '\0';
24 const char *filename_to_str(const Filename *fn)
29 int filename_equal(Filename f1, Filename f2)
31 return !strcmp(f1.path, f2.path);
34 int filename_is_null(Filename fn)
39 char *get_username(void)
45 if (GetUserName(NULL, &namelen) == FALSE) {
47 * Apparently this doesn't work at least on Windows XP SP2.
48 * Thus assume a maximum of 256. It will fail again if it
54 user = snewn(namelen, char);
55 GetUserName(user, &namelen);
60 BOOL init_winver(void)
62 ZeroMemory(&osVersion, sizeof(osVersion));
63 osVersion.dwOSVersionInfoSize = sizeof (OSVERSIONINFO);
64 return GetVersionEx ( (OSVERSIONINFO *) &osVersion);
68 static FILE *debug_fp = NULL;
69 static HANDLE debug_hdl = INVALID_HANDLE_VALUE;
70 static int debug_got_console = 0;
76 if (!debug_got_console) {
78 debug_got_console = 1;
79 debug_hdl = GetStdHandle(STD_OUTPUT_HANDLE);
83 debug_fp = fopen("debug.log", "w");
86 if (debug_hdl != INVALID_HANDLE_VALUE) {
87 WriteFile(debug_hdl, buf, strlen(buf), &dw, NULL);
96 * Minefield - a Windows equivalent for Electric Fence
104 * We start by reserving as much virtual address space as Windows
105 * will sensibly (or not sensibly) let us have. We flag it all as
108 * Any allocation attempt is satisfied by committing one or more
109 * pages, with an uncommitted page on either side. The returned
110 * memory region is jammed up against the _end_ of the pages.
112 * Freeing anything causes instantaneous decommitment of the pages
113 * involved, so stale pointers are caught as soon as possible.
116 static int minefield_initialised = 0;
117 static void *minefield_region = NULL;
118 static long minefield_size = 0;
119 static long minefield_npages = 0;
120 static long minefield_curpos = 0;
121 static unsigned short *minefield_admin = NULL;
122 static void *minefield_pages = NULL;
124 static void minefield_admin_hide(int hide)
126 int access = hide ? PAGE_NOACCESS : PAGE_READWRITE;
127 VirtualProtect(minefield_admin, minefield_npages * 2, access, NULL);
130 static void minefield_init(void)
136 for (size = 0x40000000; size > 0; size = ((size >> 3) * 7) & ~0xFFF) {
137 minefield_region = VirtualAlloc(NULL, size,
138 MEM_RESERVE, PAGE_NOACCESS);
139 if (minefield_region)
142 minefield_size = size;
145 * Firstly, allocate a section of that to be the admin block.
146 * We'll need a two-byte field for each page.
148 minefield_admin = minefield_region;
149 minefield_npages = minefield_size / PAGESIZE;
150 admin_size = (minefield_npages * 2 + PAGESIZE - 1) & ~(PAGESIZE - 1);
151 minefield_npages = (minefield_size - admin_size) / PAGESIZE;
152 minefield_pages = (char *) minefield_region + admin_size;
155 * Commit the admin region.
157 VirtualAlloc(minefield_admin, minefield_npages * 2,
158 MEM_COMMIT, PAGE_READWRITE);
161 * Mark all pages as unused (0xFFFF).
163 for (i = 0; i < minefield_npages; i++)
164 minefield_admin[i] = 0xFFFF;
167 * Hide the admin region.
169 minefield_admin_hide(1);
171 minefield_initialised = 1;
174 static void minefield_bomb(void)
176 div(1, *(int *) minefield_pages);
179 static void *minefield_alloc(int size)
182 int pos, lim, region_end, region_start;
186 npages = (size + PAGESIZE - 1) / PAGESIZE;
188 minefield_admin_hide(0);
191 * Search from current position until we find a contiguous
192 * bunch of npages+2 unused pages.
194 pos = minefield_curpos;
195 lim = minefield_npages;
197 /* Skip over used pages. */
198 while (pos < lim && minefield_admin[pos] != 0xFFFF)
200 /* Count unused pages. */
202 while (pos < lim && pos - start < npages + 2 &&
203 minefield_admin[pos] == 0xFFFF)
205 if (pos - start == npages + 2)
207 /* If we've reached the limit, reset the limit or stop. */
209 if (lim == minefield_npages) {
210 /* go round and start again at zero */
211 lim = minefield_curpos;
214 minefield_admin_hide(1);
220 minefield_curpos = pos - 1;
223 * We have npages+2 unused pages starting at start. We leave
224 * the first and last of these alone and use the rest.
226 region_end = (start + npages + 1) * PAGESIZE;
227 region_start = region_end - size;
228 /* FIXME: could align here if we wanted */
231 * Update the admin region.
233 for (i = start + 2; i < start + npages + 1; i++)
234 minefield_admin[i] = 0xFFFE; /* used but no region starts here */
235 minefield_admin[start + 1] = region_start % PAGESIZE;
237 minefield_admin_hide(1);
239 VirtualAlloc((char *) minefield_pages + region_start, size,
240 MEM_COMMIT, PAGE_READWRITE);
241 return (char *) minefield_pages + region_start;
244 static void minefield_free(void *ptr)
246 int region_start, i, j;
248 minefield_admin_hide(0);
250 region_start = (char *) ptr - (char *) minefield_pages;
251 i = region_start / PAGESIZE;
252 if (i < 0 || i >= minefield_npages ||
253 minefield_admin[i] != region_start % PAGESIZE)
255 for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++) {
256 minefield_admin[j] = 0xFFFF;
259 VirtualFree(ptr, j * PAGESIZE - region_start, MEM_DECOMMIT);
261 minefield_admin_hide(1);
264 static int minefield_get_size(void *ptr)
266 int region_start, i, j;
268 minefield_admin_hide(0);
270 region_start = (char *) ptr - (char *) minefield_pages;
271 i = region_start / PAGESIZE;
272 if (i < 0 || i >= minefield_npages ||
273 minefield_admin[i] != region_start % PAGESIZE)
275 for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++);
277 minefield_admin_hide(1);
279 return j * PAGESIZE - region_start;
282 void *minefield_c_malloc(size_t size)
284 if (!minefield_initialised)
286 return minefield_alloc(size);
289 void minefield_c_free(void *p)
291 if (!minefield_initialised)
297 * realloc _always_ moves the chunk, for rapid detection of code
298 * that assumes it won't.
300 void *minefield_c_realloc(void *p, size_t size)
304 if (!minefield_initialised)
306 q = minefield_alloc(size);
307 oldsize = minefield_get_size(p);
308 memcpy(q, p, (oldsize < size ? oldsize : size));
313 #endif /* MINEFIELD */