gdb/wince-stub.c

   1 /* wince-stub.c -- debugging stub for a Windows CE device
   2
   3    Copyright 1999, 2000 Free Software Foundation, Inc.
   4    Contributed by Cygnus Solutions, A Red Hat Company.
   5
   6    This file is part of GDB.
   7
   8    This program 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 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without eve nthe implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.
  22  */
  23
  24 /* by Christopher Faylor (cgf@cygnus.com) */
  25
  26 #include <stdarg.h>
  27 #include <windows.h>
  28 #include <winsock.h>
  29 #include "wince-stub.h"
  30
  31 #define MALLOC(n) (void *) LocalAlloc (LMEM_MOVEABLE | LMEM_ZEROINIT, (UINT)(n))
  32 #define REALLOC(s, n) (void *) LocalReAlloc ((HLOCAL)(s), (UINT)(n), LMEM_MOVEABLE)
  33 #define FREE(s) LocalFree ((HLOCAL)(s))
  34
  35 static int skip_next_id = 0;    /* Don't read next API code from socket */
  36
  37 /* v-style interface for handling varying argument list error messages.
  38    Displays the error message in a dialog box and exits when user clicks
  39    on OK. */
  40 static void
  41 vstub_error (LPCWSTR fmt, va_list args)
  42 {
  43   WCHAR buf[4096];
  44   wvsprintfW (buf, fmt, args);
  45
  46   MessageBoxW (NULL, buf, L"GDB", MB_ICONERROR);
  47   WSACleanup ();
  48   ExitThread (1);
  49 }
  50
  51 /* The standard way to display an error message and exit. */
  52 static void
  53 stub_error (LPCWSTR fmt, ...)
  54 {
  55   va_list args;
  56   va_start (args, fmt);
  57   vstub_error (fmt, args);
  58 }
  59
  60 /* Allocate a limited pool of memory, reallocating over unused
  61    buffers.  This assumes that there will never be more than four
  62    "buffers" required which, so far, is a safe assumption. */
  63 static LPVOID
  64 mempool (unsigned int len)
  65 {
  66   static int outn = -1;
  67   static LPWSTR outs[4] = {NULL, NULL, NULL, NULL};
  68
  69   if (++outn >= (sizeof (outs) / sizeof (outs[0])))
  70     outn = 0;
  71
  72   /* Allocate space for the converted string, reusing any previously allocated
  73      space, if applicable. */
  74   if (outs[outn])
  75     FREE (outs[outn]);
  76   outs[outn] = (LPWSTR) MALLOC (len);
  77
  78   return outs[outn];
  79 }
  80
  81 /* Standard "oh well" can't communicate error.  Someday this might attempt
  82    synchronization. */
  83 static void
  84 attempt_resync (LPCWSTR huh, int s)
  85 {
  86   stub_error (L"lost synchronization with host attempting %s.  Error %d", huh, WSAGetLastError ());
  87 }
  88
  89 /* Read arbitrary stuff from a socket. */
  90 static int
  91 sockread (LPCWSTR huh, int s, void *str, size_t n)
  92 {
  93   for (;;)
  94     {
  95       if (recv (s, str, n, 0) == (int) n)
  96         return n;
  97       attempt_resync (huh, s);
  98     }
  99 }
 100
 101 /* Write arbitrary stuff to a socket. */
 102 static int
 103 sockwrite (LPCWSTR huh, int s, const void *str, size_t n)
 104 {
 105   for (;;)
 106     {
 107       if (send (s, str, n, 0) == (int) n)
 108         return n;
 109       attempt_resync (huh, s);
 110     }
 111 }
 112
 113 /* Get a an ID (possibly) and a DWORD from the host gdb.
 114    Don't bother with the id if the main loop has already
 115    read it. */
 116 static DWORD
 117 getdword (LPCWSTR huh, int s, gdb_wince_id what_this)
 118 {
 119   DWORD n;
 120   gdb_wince_id what;
 121
 122   if (skip_next_id)
 123     skip_next_id = 0;
 124   else
 125     do
 126       if (sockread (huh, s, &what, sizeof (what)) != sizeof (what))
 127         stub_error (L"error getting record type from host - %s.", huh);
 128     while (what_this != what);
 129
 130   if (sockread (huh, s, &n, sizeof (n)) != sizeof (n))
 131     stub_error (L"error getting %s from host.", huh);
 132
 133   return n;
 134 }
 135
 136 /* Get a an ID (possibly) and a WORD from the host gdb.
 137    Don't bother with the id if the main loop has already
 138    read it. */
 139 static WORD
 140 getword (LPCWSTR huh, int s, gdb_wince_id what_this)
 141 {
 142   WORD n;
 143   gdb_wince_id what;
 144
 145   if (skip_next_id)
 146     skip_next_id = 0;
 147   else
 148     do
 149       if (sockread (huh, s, &what, sizeof (what)) != sizeof (what))
 150         stub_error (L"error getting record type from host - %s.", huh);
 151     while (what_this != what);
 152
 153   if (sockread (huh, s, &n, sizeof (n)) != sizeof (n))
 154     stub_error (L"error getting %s from host.", huh);
 155
 156   return n;
 157 }
 158
 159 /* Handy defines for getting various types of values. */
 160 #define gethandle(huh, s, what) (HANDLE) getdword ((huh), (s), (what))
 161 #define getpvoid(huh, s, what) (LPVOID) getdword ((huh), (s), (what))
 162 #define getlen(huh, s, what) (gdb_wince_len) getword ((huh), (s), (what))
 163
 164 /* Get an arbitrary block of memory from the gdb host.  This comes in
 165    two chunks an id/dword representing the length and the stream of memory
 166    itself. Returns a pointer, allocated via mempool, to a memory buffer. */
 167 static LPWSTR
 168 getmemory (LPCWSTR huh, int s, gdb_wince_id what, gdb_wince_len *inlen)
 169 {
 170   LPVOID p;
 171   gdb_wince_len dummy;
 172
 173   if (!inlen)
 174     inlen = &dummy;
 175
 176   *inlen = getlen (huh, s, what);
 177
 178   p = mempool ((unsigned int) *inlen);  /* FIXME: check for error */
 179
 180   if ((gdb_wince_len) sockread (huh, s, p, *inlen) != *inlen)
 181     stub_error (L"error getting string from host.");
 182
 183   return p;
 184 }
 185
 186 /* Output an id/dword to the host */
 187 static void
 188 putdword (LPCWSTR huh, int s, gdb_wince_id what, DWORD n)
 189 {
 190   if (sockwrite (huh, s, &what, sizeof (what)) != sizeof (what))
 191     stub_error (L"error writing record id for %s to host.", huh);
 192   if (sockwrite (huh, s, &n, sizeof (n)) != sizeof (n))
 193     stub_error (L"error writing %s to host.", huh);
 194 }
 195
 196 /* Output an id/word to the host */
 197 static void
 198 putword (LPCWSTR huh, int s, gdb_wince_id what, WORD n)
 199 {
 200   if (sockwrite (huh, s, &what, sizeof (what)) != sizeof (what))
 201     stub_error (L"error writing record id for %s to host.", huh);
 202   if (sockwrite (huh, s, &n, sizeof (n)) != sizeof (n))
 203     stub_error (L"error writing %s to host.", huh);
 204 }
 205
 206 /* Convenience define for outputting a "gdb_wince_len" type. */
 207 #define putlen(huh, s, what, n) putword ((huh), (s), (what), (gdb_wince_len) (n))
 208
 209 /* Put an arbitrary block of memory to the gdb host.  This comes in
 210    two chunks an id/dword representing the length and the stream of memory
 211    itself. */
 212 static void
 213 putmemory (LPCWSTR huh, int s, gdb_wince_id what, const void *mem, gdb_wince_len len)
 214 {
 215   putlen (huh, s, what, len);
 216   if (((short) len > 0) && (gdb_wince_len) sockwrite (huh, s, mem, len) != len)
 217     stub_error (L"error writing memory to host.");
 218 }
 219
 220 /* Output the result of an operation to the host.  If res != 0, sends a block of
 221    memory starting at mem of len bytes.  If res == 0, sends -GetLastError () and
 222    avoids sending the mem. */
 223 static void
 224 putresult (LPCWSTR huh, gdb_wince_result res, int s, gdb_wince_id what, const void *mem, gdb_wince_len len)
 225 {
 226   if (!res)
 227     len = -(int) GetLastError ();
 228   putmemory (huh, s, what, mem, len);
 229 }
 230
 231 static HANDLE curproc;          /* Currently unused, but nice for debugging */
 232
 233 /* Emulate CreateProcess.  Returns &pi if no error. */
 234 static void
 235 create_process (int s)
 236 {
 237   LPWSTR exec_file = getmemory (L"CreateProcess exec_file", s, GDB_CREATEPROCESS, NULL);
 238   LPWSTR args = getmemory (L"CreateProcess args", s, GDB_CREATEPROCESS, NULL);
 239   DWORD flags = getdword (L"CreateProcess flags", s, GDB_CREATEPROCESS);
 240   PROCESS_INFORMATION pi;
 241   gdb_wince_result res;
 242
 243   res = CreateProcessW (exec_file,
 244                         args,   /* command line */
 245                         NULL,   /* Security */
 246                         NULL,   /* thread */
 247                         FALSE,  /* inherit handles */
 248                         flags,  /* start flags */
 249                         NULL,
 250                         NULL,   /* current directory */
 251                         NULL,
 252                         &pi);
 253   putresult (L"CreateProcess", res, s, GDB_CREATEPROCESS, &pi, sizeof (pi));
 254   curproc = pi.hProcess;
 255 }
 256
 257 /* Emulate TerminateProcess.  Returns return value of TerminateProcess if
 258    no error.
 259    *** NOTE:  For some unknown reason, TerminateProcess seems to always return
 260    an ACCESS_DENIED (on Windows CE???) error.  So, force a TRUE value for now. */
 261 static void
 262 terminate_process (int s)
 263 {
 264   gdb_wince_result res;
 265   HANDLE h = gethandle (L"TerminateProcess handle", s, GDB_TERMINATEPROCESS);
 266
 267   res = TerminateProcess (h, 0) || 1;   /* Doesn't seem to work on SH so default to TRUE */
 268   putresult (L"Terminate process result", res, s, GDB_TERMINATEPROCESS,
 269              &res, sizeof (res));
 270 }
 271
 272 static int stepped = 0;
 273 /* Handle single step instruction.  FIXME: unneded? */
 274 static void
 275 flag_single_step (int s)
 276 {
 277   stepped = 1;
 278   skip_next_id = 0;
 279 }
 280
 281 struct skipper
 282 {
 283   wchar_t *s;
 284   int nskip;
 285 } skippy[] =
 286 {
 287   {L"Undefined Instruction:", 1},
 288   {L"Data Abort:", 2},
 289   {NULL, 0}
 290 };
 291
 292 static int
 293 skip_message (DEBUG_EVENT *ev)
 294 {
 295   char s[80];
 296   DWORD nread;
 297   struct skipper *skp;
 298   int nbytes = ev->u.DebugString.nDebugStringLength;
 299
 300   if (nbytes > sizeof(s))
 301     nbytes = sizeof(s);
 302
 303   memset (s, 0, sizeof (s));
 304   if (!ReadProcessMemory (curproc, ev->u.DebugString.lpDebugStringData,
 305                           s, nbytes, &nread))
 306     return 0;
 307
 308   for (skp = skippy; skp->s != NULL; skp++)
 309     if (wcsncmp ((wchar_t *) s, skp->s, wcslen (skp->s)) == 0)
 310       return skp->nskip;
 311
 312   return 0;
 313 }
 314
 315 /* Emulate WaitForDebugEvent.  Returns the debug event on success. */
 316 static void
 317 wait_for_debug_event (int s)
 318 {
 319   DWORD ms = getdword (L"WaitForDebugEvent ms", s, GDB_WAITFORDEBUGEVENT);
 320   gdb_wince_result res;
 321   DEBUG_EVENT ev;
 322   static int skip_next = 0;
 323
 324   for (;;)
 325     {
 326       res = WaitForDebugEvent (&ev, ms);
 327
 328       if (ev.dwDebugEventCode == OUTPUT_DEBUG_STRING_EVENT)
 329         {
 330           if (skip_next)
 331             {
 332               skip_next--;
 333               goto ignore;
 334             }
 335           if (skip_next = skip_message (&ev))
 336             goto ignore;
 337         }
 338
 339       putresult (L"WaitForDebugEvent event", res, s, GDB_WAITFORDEBUGEVENT,
 340                  &ev, sizeof (ev));
 341       break;
 342
 343     ignore:
 344       ContinueDebugEvent (ev.dwProcessId, ev.dwThreadId, DBG_CONTINUE);
 345     }
 346
 347   return;
 348 }
 349
 350 /* Emulate GetThreadContext.  Returns CONTEXT structure on success. */
 351 static void
 352 get_thread_context (int s)
 353 {
 354   CONTEXT c;
 355   HANDLE h = gethandle (L"GetThreadContext handle", s, GDB_GETTHREADCONTEXT);
 356   gdb_wince_result res;
 357
 358   memset (&c, 0, sizeof (c));
 359   c.ContextFlags = getdword (L"GetThreadContext flags", s, GDB_GETTHREADCONTEXT);
 360
 361   res = (gdb_wince_result) GetThreadContext (h, &c);
 362   putresult (L"GetThreadContext data", res, s, GDB_GETTHREADCONTEXT,
 363              &c, sizeof (c));
 364 }
 365
 366 /* Emulate GetThreadContext.  Returns success of SetThreadContext. */
 367 static void
 368 set_thread_context (int s)
 369 {
 370   gdb_wince_result res;
 371   HANDLE h = gethandle (L"SetThreadContext handle", s, GDB_SETTHREADCONTEXT);
 372   LPCONTEXT pc = (LPCONTEXT) getmemory (L"SetThreadContext context", s,
 373                                         GDB_SETTHREADCONTEXT, NULL);
 374
 375   res = SetThreadContext (h, pc);
 376   putresult (L"SetThreadContext result", res, s, GDB_SETTHREADCONTEXT,
 377              &res, sizeof (res));
 378 }
 379
 380 /* Emulate ReadProcessMemory.  Returns memory read on success. */
 381 static void
 382 read_process_memory (int s)
 383 {
 384   HANDLE h = gethandle (L"ReadProcessMemory handle", s, GDB_READPROCESSMEMORY);
 385   LPVOID p = getpvoid (L"ReadProcessMemory base", s, GDB_READPROCESSMEMORY);
 386   gdb_wince_len len = getlen (L"ReadProcessMemory size", s, GDB_READPROCESSMEMORY);
 387   LPVOID buf = mempool ((unsigned int) len);
 388   DWORD outlen;
 389   gdb_wince_result res;
 390
 391   outlen = 0;
 392   res = (gdb_wince_result) ReadProcessMemory (h, p, buf, len, &outlen);
 393   putresult (L"ReadProcessMemory data", res, s, GDB_READPROCESSMEMORY,
 394              buf, (gdb_wince_len) outlen);
 395 }
 396
 397 /* Emulate WriteProcessMemory.  Returns WriteProcessMemory success. */
 398 static void
 399 write_process_memory (int s)
 400 {
 401   HANDLE h = gethandle (L"WriteProcessMemory handle", s, GDB_WRITEPROCESSMEMORY);
 402   LPVOID p = getpvoid (L"WriteProcessMemory base", s, GDB_WRITEPROCESSMEMORY);
 403   gdb_wince_len len;
 404   LPVOID buf = getmemory (L"WriteProcessMemory buf", s, GDB_WRITEPROCESSMEMORY, &len);
 405   DWORD outlen;
 406   gdb_wince_result res;
 407
 408   outlen = 0;
 409   res = WriteProcessMemory (h, p, buf, (DWORD) len, &outlen);
 410   putresult (L"WriteProcessMemory data", res, s, GDB_WRITEPROCESSMEMORY,
 411              (gdb_wince_len *) & outlen, sizeof (gdb_wince_len));
 412 }
 413
 414 /* Return non-zero to gdb host if given thread is alive. */
 415 static void
 416 thread_alive (int s)
 417 {
 418   HANDLE h = gethandle (L"ThreadAlive handle", s, GDB_THREADALIVE);
 419   gdb_wince_result res;
 420
 421   res = WaitForSingleObject (h, 0) == WAIT_OBJECT_0 ? 1 : 0;
 422   putresult (L"WriteProcessMemory data", res, s, GDB_THREADALIVE,
 423              &res, sizeof (res));
 424 }
 425
 426 /* Emulate SuspendThread.  Returns value returned from SuspendThread. */
 427 static void
 428 suspend_thread (int s)
 429 {
 430   DWORD res;
 431   HANDLE h = gethandle (L"SuspendThread handle", s, GDB_SUSPENDTHREAD);
 432   res = SuspendThread (h);
 433   putdword (L"SuspendThread result", s, GDB_SUSPENDTHREAD, res);
 434 }
 435
 436 /* Emulate ResumeThread.  Returns value returned from ResumeThread. */
 437 static void
 438 resume_thread (int s)
 439 {
 440   DWORD res;
 441   HANDLE h = gethandle (L"ResumeThread handle", s, GDB_RESUMETHREAD);
 442   res = ResumeThread (h);
 443   putdword (L"ResumeThread result", s, GDB_RESUMETHREAD, res);
 444 }
 445
 446 /* Emulate ContinueDebugEvent.  Returns ContinueDebugEvent success. */
 447 static void
 448 continue_debug_event (int s)
 449 {
 450   gdb_wince_result res;
 451   DWORD pid = getdword (L"ContinueDebugEvent pid", s, GDB_CONTINUEDEBUGEVENT);
 452   DWORD tid = getdword (L"ContinueDebugEvent tid", s, GDB_CONTINUEDEBUGEVENT);
 453   DWORD status = getdword (L"ContinueDebugEvent status", s, GDB_CONTINUEDEBUGEVENT);
 454   res = (gdb_wince_result) ContinueDebugEvent (pid, tid, status);
 455   putresult (L"ContinueDebugEvent result", res, s, GDB_CONTINUEDEBUGEVENT, &res, sizeof (res));
 456 }
 457
 458 /* Emulate CloseHandle.  Returns CloseHandle success. */
 459 static void
 460 close_handle (int s)
 461 {
 462   gdb_wince_result res;
 463   HANDLE h = gethandle (L"CloseHandle handle", s, GDB_CLOSEHANDLE);
 464   res = (gdb_wince_result) CloseHandle (h);
 465   putresult (L"CloseHandle result", res, s, GDB_CLOSEHANDLE, &res, sizeof (res));
 466 }
 467
 468 /* Main loop for reading requests from gdb host on the socket. */
 469 static void
 470 dispatch (int s)
 471 {
 472   gdb_wince_id id;
 473
 474   /* Continue reading from socket until receive a GDB_STOPSUB. */
 475   while (sockread (L"Dispatch", s, &id, sizeof (id)) > 0)
 476     {
 477       skip_next_id = 1;
 478       switch (id)
 479         {
 480         case GDB_CREATEPROCESS:
 481           create_process (s);
 482           break;
 483         case GDB_TERMINATEPROCESS:
 484           terminate_process (s);
 485           break;
 486         case GDB_WAITFORDEBUGEVENT:
 487           wait_for_debug_event (s);
 488           break;
 489         case GDB_GETTHREADCONTEXT:
 490           get_thread_context (s);
 491           break;
 492         case GDB_SETTHREADCONTEXT:
 493           set_thread_context (s);
 494           break;
 495         case GDB_READPROCESSMEMORY:
 496           read_process_memory (s);
 497           break;
 498         case GDB_WRITEPROCESSMEMORY:
 499           write_process_memory (s);
 500           break;
 501         case GDB_THREADALIVE:
 502           thread_alive (s);
 503           break;
 504         case GDB_SUSPENDTHREAD:
 505           suspend_thread (s);
 506           break;
 507         case GDB_RESUMETHREAD:
 508           resume_thread (s);
 509           break;
 510         case GDB_CONTINUEDEBUGEVENT:
 511           continue_debug_event (s);
 512           break;
 513         case GDB_CLOSEHANDLE:
 514           close_handle (s);
 515           break;
 516         case GDB_STOPSTUB:
 517           terminate_process (s);
 518           return;
 519         case GDB_SINGLESTEP:
 520           flag_single_step (s);
 521           break;
 522         default:
 523           {
 524             WCHAR buf[80];
 525             wsprintfW (buf, L"Invalid command id received: %d", id);
 526             MessageBoxW (NULL, buf, L"GDB", MB_ICONERROR);
 527             skip_next_id = 0;
 528           }
 529         }
 530     }
 531 }
 532
 533 /* The Windows Main entry point */
 534 int WINAPI
 535 WinMain (HINSTANCE hi, HINSTANCE hp, LPWSTR cmd, int show)
 536 {
 537   struct hostent *h;
 538   int s;
 539   struct WSAData wd;
 540   struct sockaddr_in sin;
 541   int tmp;
 542   LPWSTR whost;
 543   char host[80];
 544
 545   whost = wcschr (cmd, L' ');   /* Look for argument. */
 546
 547   /* If no host is specified, just use default */
 548   if (whost)
 549     {
 550       /* Eat any spaces. */
 551       while (*whost == L' ' || *whost == L'\t')
 552         whost++;
 553
 554       wcstombs (host, whost, 80);       /* Convert from UNICODE to ascii */
 555     }
 556
 557   /* Winsock initialization. */
 558   if (WSAStartup (MAKEWORD (1, 1), &wd))
 559     stub_error (L"Couldn't initialize WINSOCK.");
 560
 561   /* If whost was specified, first try it.  If it was not specified or the
 562      host lookup failed, try the Windows CE magic ppp_peer lookup.  ppp_peer
 563      is supposed to be the Windows host sitting on the other end of the
 564      serial cable. */
 565   if (whost && *whost && (h = gethostbyname (host)) != NULL)
 566     /* nothing to do */ ;
 567   else if ((h = gethostbyname ("ppp_peer")) == NULL)
 568     stub_error (L"Couldn't get IP address of host system.  Error %d", WSAGetLastError ());
 569
 570   /* Get a socket. */
 571   if ((s = socket (AF_INET, SOCK_STREAM, 0)) < 0)
 572     stub_error (L"Couldn't connect to host system. Error %d", WSAGetLastError ());
 573
 574   /* Allow rapid reuse of the port. */
 575   tmp = 1;
 576   setsockopt (s, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp, sizeof (tmp));
 577
 578   /* Set up the information for connecting to the host gdb process. */
 579   memset (&sin, 0, sizeof (sin));
 580   sin.sin_family = h->h_addrtype;
 581   memcpy (&sin.sin_addr, h->h_addr, h->h_length);
 582   sin.sin_port = htons (7000);  /* FIXME: This should be configurable */
 583
 584   /* Connect to host */
 585   if (connect (s, (struct sockaddr *) &sin, sizeof (sin)) < 0)
 586     stub_error (L"Couldn't connect to host gdb.");
 587
 588   /* Read from socket until told to exit. */
 589   dispatch (s);
 590   WSACleanup ();
 591   return 0;
 592 }