git.distorted.org.uk Git - u/mdw/putty/blob - winmisc.c

   1 /*
   2  * winmisc.c: miscellaneous Windows-specific things
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include "putty.h"
   8
   9 OSVERSIONINFO osVersion;
  10
  11 void platform_get_x11_auth(char *display, int *proto,
  12                            unsigned char *data, int *datalen)
  13 {
  14     /* We don't support this at all under Windows. */
  15 }
  16
  17 const char platform_x11_best_transport[] = "localhost";
  18
  19 char *platform_get_x_display(void) {
  20     /* We may as well check for DISPLAY in case it's useful. */
  21     return dupstr(getenv("DISPLAY"));
  22 }
  23
  24 Filename filename_from_str(const char *str)
  25 {
  26     Filename ret;
  27     strncpy(ret.path, str, sizeof(ret.path));
  28     ret.path[sizeof(ret.path)-1] = '\0';
  29     return ret;
  30 }
  31
  32 const char *filename_to_str(const Filename *fn)
  33 {
  34     return fn->path;
  35 }
  36
  37 int filename_equal(Filename f1, Filename f2)
  38 {
  39     return !strcmp(f1.path, f2.path);
  40 }
  41
  42 int filename_is_null(Filename fn)
  43 {
  44     return !*fn.path;
  45 }
  46
  47 char *get_username(void)
  48 {
  49     DWORD namelen;
  50     char *user;
  51
  52     namelen = 0;
  53     if (GetUserName(NULL, &namelen) == FALSE)
  54         return NULL;
  55
  56     user = snewn(namelen, char);
  57     GetUserName(user, &namelen);
  58
  59     return user;
  60 }
  61
  62 int SaneDialogBox(HINSTANCE hinst,
  63                   LPCTSTR tmpl,
  64                   HWND hwndparent,
  65                   DLGPROC lpDialogFunc)
  66 {
  67     WNDCLASS wc;
  68     HWND hwnd;
  69     MSG msg;
  70     int flags;
  71     int ret;
  72     int gm;
  73
  74     wc.style = CS_DBLCLKS | CS_SAVEBITS | CS_BYTEALIGNWINDOW;
  75     wc.lpfnWndProc = DefDlgProc;
  76     wc.cbClsExtra = 0;
  77     wc.cbWndExtra = DLGWINDOWEXTRA + 8;
  78     wc.hInstance = hinst;
  79     wc.hIcon = NULL;
  80     wc.hCursor = LoadCursor(NULL, IDC_ARROW);
  81     wc.hbrBackground = (HBRUSH) (COLOR_BACKGROUND +1);
  82     wc.lpszMenuName = NULL;
  83     wc.lpszClassName = "PuTTYConfigBox";
  84     RegisterClass(&wc);
  85
  86     hwnd = CreateDialog(hinst, tmpl, hwndparent, lpDialogFunc);
  87
  88     SetWindowLong(hwnd, BOXFLAGS, 0); /* flags */
  89     SetWindowLong(hwnd, BOXRESULT, 0); /* result from SaneEndDialog */
  90
  91     while ((gm=GetMessage(&msg, NULL, 0, 0)) > 0) {
  92         flags=GetWindowLong(hwnd, BOXFLAGS);
  93         if (!(flags & DF_END) && !IsDialogMessage(hwnd, &msg))
  94             DispatchMessage(&msg);
  95         if (flags & DF_END)
  96             break;
  97     }
  98
  99     if (gm == 0)
 100         PostQuitMessage(msg.wParam); /* We got a WM_QUIT, pass it on */
 101
 102     ret=GetWindowLong(hwnd, BOXRESULT);
 103     DestroyWindow(hwnd);
 104     return ret;
 105 }
 106
 107 void SaneEndDialog(HWND hwnd, int ret)
 108 {
 109     SetWindowLong(hwnd, BOXRESULT, ret);
 110     SetWindowLong(hwnd, BOXFLAGS, DF_END);
 111 }
 112
 113 BOOL init_winver(void)
 114 {
 115     ZeroMemory(&osVersion, sizeof(osVersion));
 116     osVersion.dwOSVersionInfoSize = sizeof (OSVERSIONINFO);
 117     return GetVersionEx ( (OSVERSIONINFO *) &osVersion);
 118 }
 119
 120 #ifdef DEBUG
 121 static FILE *debug_fp = NULL;
 122 static HANDLE debug_hdl = INVALID_HANDLE_VALUE;
 123 static int debug_got_console = 0;
 124
 125 void dputs(char *buf)
 126 {
 127     DWORD dw;
 128
 129     if (!debug_got_console) {
 130         if (AllocConsole()) {
 131             debug_got_console = 1;
 132             debug_hdl = GetStdHandle(STD_OUTPUT_HANDLE);
 133         }
 134     }
 135     if (!debug_fp) {
 136         debug_fp = fopen("debug.log", "w");
 137     }
 138
 139     if (debug_hdl != INVALID_HANDLE_VALUE) {
 140         WriteFile(debug_hdl, buf, strlen(buf), &dw, NULL);
 141     }
 142     fputs(buf, debug_fp);
 143     fflush(debug_fp);
 144 }
 145 #endif
 146
 147 #ifdef MINEFIELD
 148 /*
 149  * Minefield - a Windows equivalent for Electric Fence
 150  */
 151
 152 #define PAGESIZE 4096
 153
 154 /*
 155  * Design:
 156  *
 157  * We start by reserving as much virtual address space as Windows
 158  * will sensibly (or not sensibly) let us have. We flag it all as
 159  * invalid memory.
 160  *
 161  * Any allocation attempt is satisfied by committing one or more
 162  * pages, with an uncommitted page on either side. The returned
 163  * memory region is jammed up against the _end_ of the pages.
 164  *
 165  * Freeing anything causes instantaneous decommitment of the pages
 166  * involved, so stale pointers are caught as soon as possible.
 167  */
 168
 169 static int minefield_initialised = 0;
 170 static void *minefield_region = NULL;
 171 static long minefield_size = 0;
 172 static long minefield_npages = 0;
 173 static long minefield_curpos = 0;
 174 static unsigned short *minefield_admin = NULL;
 175 static void *minefield_pages = NULL;
 176
 177 static void minefield_admin_hide(int hide)
 178 {
 179     int access = hide ? PAGE_NOACCESS : PAGE_READWRITE;
 180     VirtualProtect(minefield_admin, minefield_npages * 2, access, NULL);
 181 }
 182
 183 static void minefield_init(void)
 184 {
 185     int size;
 186     int admin_size;
 187     int i;
 188
 189     for (size = 0x40000000; size > 0; size = ((size >> 3) * 7) & ~0xFFF) {
 190         minefield_region = VirtualAlloc(NULL, size,
 191                                         MEM_RESERVE, PAGE_NOACCESS);
 192         if (minefield_region)
 193             break;
 194     }
 195     minefield_size = size;
 196
 197     /*
 198      * Firstly, allocate a section of that to be the admin block.
 199      * We'll need a two-byte field for each page.
 200      */
 201     minefield_admin = minefield_region;
 202     minefield_npages = minefield_size / PAGESIZE;
 203     admin_size = (minefield_npages * 2 + PAGESIZE - 1) & ~(PAGESIZE - 1);
 204     minefield_npages = (minefield_size - admin_size) / PAGESIZE;
 205     minefield_pages = (char *) minefield_region + admin_size;
 206
 207     /*
 208      * Commit the admin region.
 209      */
 210     VirtualAlloc(minefield_admin, minefield_npages * 2,
 211                  MEM_COMMIT, PAGE_READWRITE);
 212
 213     /*
 214      * Mark all pages as unused (0xFFFF).
 215      */
 216     for (i = 0; i < minefield_npages; i++)
 217         minefield_admin[i] = 0xFFFF;
 218
 219     /*
 220      * Hide the admin region.
 221      */
 222     minefield_admin_hide(1);
 223
 224     minefield_initialised = 1;
 225 }
 226
 227 static void minefield_bomb(void)
 228 {
 229     div(1, *(int *) minefield_pages);
 230 }
 231
 232 static void *minefield_alloc(int size)
 233 {
 234     int npages;
 235     int pos, lim, region_end, region_start;
 236     int start;
 237     int i;
 238
 239     npages = (size + PAGESIZE - 1) / PAGESIZE;
 240
 241     minefield_admin_hide(0);
 242
 243     /*
 244      * Search from current position until we find a contiguous
 245      * bunch of npages+2 unused pages.
 246      */
 247     pos = minefield_curpos;
 248     lim = minefield_npages;
 249     while (1) {
 250         /* Skip over used pages. */
 251         while (pos < lim && minefield_admin[pos] != 0xFFFF)
 252             pos++;
 253         /* Count unused pages. */
 254         start = pos;
 255         while (pos < lim && pos - start < npages + 2 &&
 256                minefield_admin[pos] == 0xFFFF)
 257             pos++;
 258         if (pos - start == npages + 2)
 259             break;
 260         /* If we've reached the limit, reset the limit or stop. */
 261         if (pos >= lim) {
 262             if (lim == minefield_npages) {
 263                 /* go round and start again at zero */
 264                 lim = minefield_curpos;
 265                 pos = 0;
 266             } else {
 267                 minefield_admin_hide(1);
 268                 return NULL;
 269             }
 270         }
 271     }
 272
 273     minefield_curpos = pos - 1;
 274
 275     /*
 276      * We have npages+2 unused pages starting at start. We leave
 277      * the first and last of these alone and use the rest.
 278      */
 279     region_end = (start + npages + 1) * PAGESIZE;
 280     region_start = region_end - size;
 281     /* FIXME: could align here if we wanted */
 282
 283     /*
 284      * Update the admin region.
 285      */
 286     for (i = start + 2; i < start + npages + 1; i++)
 287         minefield_admin[i] = 0xFFFE;   /* used but no region starts here */
 288     minefield_admin[start + 1] = region_start % PAGESIZE;
 289
 290     minefield_admin_hide(1);
 291
 292     VirtualAlloc((char *) minefield_pages + region_start, size,
 293                  MEM_COMMIT, PAGE_READWRITE);
 294     return (char *) minefield_pages + region_start;
 295 }
 296
 297 static void minefield_free(void *ptr)
 298 {
 299     int region_start, i, j;
 300
 301     minefield_admin_hide(0);
 302
 303     region_start = (char *) ptr - (char *) minefield_pages;
 304     i = region_start / PAGESIZE;
 305     if (i < 0 || i >= minefield_npages ||
 306         minefield_admin[i] != region_start % PAGESIZE)
 307         minefield_bomb();
 308     for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++) {
 309         minefield_admin[j] = 0xFFFF;
 310     }
 311
 312     VirtualFree(ptr, j * PAGESIZE - region_start, MEM_DECOMMIT);
 313
 314     minefield_admin_hide(1);
 315 }
 316
 317 static int minefield_get_size(void *ptr)
 318 {
 319     int region_start, i, j;
 320
 321     minefield_admin_hide(0);
 322
 323     region_start = (char *) ptr - (char *) minefield_pages;
 324     i = region_start / PAGESIZE;
 325     if (i < 0 || i >= minefield_npages ||
 326         minefield_admin[i] != region_start % PAGESIZE)
 327         minefield_bomb();
 328     for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++);
 329
 330     minefield_admin_hide(1);
 331
 332     return j * PAGESIZE - region_start;
 333 }
 334
 335 void *minefield_c_malloc(size_t size)
 336 {
 337     if (!minefield_initialised)
 338         minefield_init();
 339     return minefield_alloc(size);
 340 }
 341
 342 void minefield_c_free(void *p)
 343 {
 344     if (!minefield_initialised)
 345         minefield_init();
 346     minefield_free(p);
 347 }
 348
 349 /*
 350  * realloc _always_ moves the chunk, for rapid detection of code
 351  * that assumes it won't.
 352  */
 353 void *minefield_c_realloc(void *p, size_t size)
 354 {
 355     size_t oldsize;
 356     void *q;
 357     if (!minefield_initialised)
 358         minefield_init();
 359     q = minefield_alloc(size);
 360     oldsize = minefield_get_size(p);
 361     memcpy(q, p, (oldsize < size ? oldsize : size));
 362     minefield_free(p);
 363     return q;
 364 }
 365
 366 #endif                          /* MINEFIELD */