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

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