programs/winedbg/stack.c

   1 /*
   2  * Debugger stack handling
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  * Copyright 1996 Eric Youngdale
   6  * Copyright 1999 Ove Kåven
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  21  */
  22
  23 #include "config.h"
  24
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27
  28 #include "debugger.h"
  29 #include "winbase.h"
  30 #include "wine/winbase16.h"
  31 #include "tlhelp32.h"
  32
  33 /***********************************************************************
  34  *           stack_info
  35  *
  36  * Dump the top of the stack
  37  */
  38 void stack_info(void)
  39 {
  40     struct dbg_lvalue lvalue;
  41
  42     lvalue.cookie = 0;
  43     lvalue.type.id = dbg_itype_segptr;
  44     lvalue.type.module = 0;
  45
  46     /* FIXME: we assume stack grows the same way as on i386 */
  47     if (!memory_get_current_stack(&lvalue.addr))
  48         dbg_printf("Bad segment (%d)\n", lvalue.addr.Segment);
  49
  50     dbg_printf("Stack dump:\n");
  51     switch (lvalue.addr.Mode)
  52     {
  53     case AddrModeFlat: /* 32-bit or 64-bit mode */
  54         memory_examine(&lvalue, 24, 'a');
  55         break;
  56     case AddrMode1632: /* 32-bit mode */
  57         memory_examine(&lvalue, 24, 'x');
  58         break;
  59     case AddrModeReal:  /* 16-bit mode */
  60     case AddrMode1616:
  61         memory_examine(&lvalue, 24, 'w');
  62         break;
  63     }
  64 }
  65
  66 static BOOL stack_set_frame_internal(int newframe)
  67 {
  68     if (newframe >= dbg_curr_thread->num_frames)
  69         newframe = dbg_curr_thread->num_frames - 1;
  70     if (newframe < 0)
  71         newframe = 0;
  72
  73     if (dbg_curr_thread->curr_frame != newframe)
  74     {
  75         IMAGEHLP_STACK_FRAME    ihsf;
  76
  77         dbg_curr_thread->curr_frame = newframe;
  78         stack_get_current_frame(&ihsf);
  79         SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
  80     }
  81     return TRUE;
  82 }
  83
  84 static BOOL stack_get_frame(int nf, IMAGEHLP_STACK_FRAME* ihsf)
  85 {
  86     memset(ihsf, 0, sizeof(*ihsf));
  87     ihsf->InstructionOffset = dbg_curr_thread->frames[nf].linear_pc;
  88     /* if we're not the first frame, InstructionOffset is the return address
  89      * after the call instruction (at least on most processors I know of).
  90      * However, there are cases where this address is outside of the current function.
  91      * This happens when the called function is marked <NO RETURN>, in which
  92      * case the compiler can omit the epilog (gcc 4 does it)
  93      * Therefore, we decrement InstructionOffset in order to ensure that
  94      * the considered address is really inside the current function.
  95      */
  96     if (nf) ihsf->InstructionOffset--;
  97     ihsf->FrameOffset = dbg_curr_thread->frames[nf].linear_frame;
  98     ihsf->StackOffset = dbg_curr_thread->frames[nf].linear_stack;
  99     return TRUE;
 100 }
 101
 102 BOOL stack_get_current_frame(IMAGEHLP_STACK_FRAME* ihsf)
 103 {
 104     /*
 105      * If we don't have a valid backtrace, then just return.
 106      */
 107     if (dbg_curr_thread->frames == NULL) return FALSE;
 108     return stack_get_frame(dbg_curr_thread->curr_frame, ihsf);
 109 }
 110
 111 BOOL stack_get_register_current_frame(unsigned regno, DWORD_PTR** pval)
 112 {
 113     enum be_cpu_addr            kind;
 114
 115     if (dbg_curr_thread->frames == NULL) return FALSE;
 116
 117     if (!be_cpu->get_register_info(regno, &kind)) return FALSE;
 118
 119     switch (kind)
 120     {
 121     case be_cpu_addr_pc:
 122         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_pc;
 123         break;
 124     case be_cpu_addr_stack:
 125         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_stack;
 126         break;
 127     case be_cpu_addr_frame:
 128         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_frame;
 129         break;
 130     }
 131     return TRUE;
 132 }
 133
 134 BOOL stack_get_register_frame(const struct dbg_internal_var* div, DWORD_PTR** pval)
 135 {
 136     if (dbg_curr_thread->frames == NULL) return FALSE;
 137     if (dbg_curr_thread->frames[dbg_curr_thread->curr_frame].is_ctx_valid)
 138         *pval = (DWORD_PTR*)((char*)&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].context +
 139                              (DWORD_PTR)div->pval);
 140     else
 141     {
 142         enum be_cpu_addr        kind;
 143
 144         if (!be_cpu->get_register_info(div->val, &kind)) return FALSE;
 145
 146         /* reuse some known registers directly out of stackwalk details */
 147         switch (kind)
 148         {
 149         case be_cpu_addr_pc:
 150             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_pc;
 151             break;
 152         case be_cpu_addr_stack:
 153             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_stack;
 154             break;
 155         case be_cpu_addr_frame:
 156             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_frame;
 157             break;
 158         }
 159     }
 160     return TRUE;
 161 }
 162
 163 BOOL stack_set_frame(int newframe)
 164 {
 165     ADDRESS64   addr;
 166     if (!stack_set_frame_internal(newframe)) return FALSE;
 167     addr.Mode = AddrModeFlat;
 168     addr.Offset = (DWORD_PTR)memory_to_linear_addr(&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].addr_pc);
 169     source_list_from_addr(&addr, 0);
 170     return TRUE;
 171 }
 172
 173 /******************************************************************
 174  *              stack_get_current_symbol
 175  *
 176  * Retrieves the symbol information for the current frame element
 177  */
 178 BOOL stack_get_current_symbol(SYMBOL_INFO* symbol)
 179 {
 180     IMAGEHLP_STACK_FRAME        ihsf;
 181     DWORD64                     disp;
 182
 183     if (!stack_get_current_frame(&ihsf)) return FALSE;
 184     return SymFromAddr(dbg_curr_process->handle, ihsf.InstructionOffset,
 185                        &disp, symbol);
 186 }
 187
 188 static BOOL CALLBACK stack_read_mem(HANDLE hProc, DWORD64 addr,
 189                                     PVOID buffer, DWORD size, PDWORD written)
 190 {
 191     SIZE_T sz;
 192     BOOL ret;
 193
 194     struct dbg_process* pcs = dbg_get_process_h(hProc);
 195     if (!pcs) return FALSE;
 196     ret = pcs->process_io->read(hProc, (const void*)(DWORD_PTR)addr, buffer,
 197                                 size, &sz);
 198     if (written != NULL) *written = sz;
 199     return ret;
 200 }
 201
 202 /******************************************************************
 203  *              stack_fetch_frames
 204  *
 205  * Do a backtrace on the current thread
 206  */
 207 unsigned stack_fetch_frames(const CONTEXT* _ctx)
 208 {
 209     STACKFRAME64 sf;
 210     unsigned     nf = 0;
 211     /* as native stackwalk can modify the context passed to it, simply copy
 212      * it to avoid any damage
 213      */
 214     CONTEXT      ctx = *_ctx, prevctx = ctx;
 215
 216     HeapFree(GetProcessHeap(), 0, dbg_curr_thread->frames);
 217     dbg_curr_thread->frames = NULL;
 218
 219     memset(&sf, 0, sizeof(sf));
 220     memory_get_current_frame(&sf.AddrFrame);
 221     memory_get_current_pc(&sf.AddrPC);
 222     memory_get_current_stack(&sf.AddrStack);
 223
 224     /* don't confuse StackWalk by passing in inconsistent addresses */
 225     if ((sf.AddrPC.Mode == AddrModeFlat) && (sf.AddrFrame.Mode != AddrModeFlat))
 226     {
 227         sf.AddrFrame.Offset = (ULONG_PTR)memory_to_linear_addr(&sf.AddrFrame);
 228         sf.AddrFrame.Mode = AddrModeFlat;
 229     }
 230
 231     while (StackWalk64(be_cpu->machine, dbg_curr_process->handle,
 232                        dbg_curr_thread->handle, &sf, &ctx, stack_read_mem,
 233                        SymFunctionTableAccess64, SymGetModuleBase64, NULL))
 234     {
 235         dbg_curr_thread->frames = dbg_heap_realloc(dbg_curr_thread->frames,
 236                                                    (nf + 1) * sizeof(dbg_curr_thread->frames[0]));
 237
 238         dbg_curr_thread->frames[nf].addr_pc      = sf.AddrPC;
 239         dbg_curr_thread->frames[nf].linear_pc    = (DWORD_PTR)memory_to_linear_addr(&sf.AddrPC);
 240         dbg_curr_thread->frames[nf].addr_frame   = sf.AddrFrame;
 241         dbg_curr_thread->frames[nf].linear_frame = (DWORD_PTR)memory_to_linear_addr(&sf.AddrFrame);
 242         dbg_curr_thread->frames[nf].addr_stack   = sf.AddrStack;
 243         dbg_curr_thread->frames[nf].linear_stack = (DWORD_PTR)memory_to_linear_addr(&sf.AddrStack);
 244         dbg_curr_thread->frames[nf].context      = prevctx;
 245         /* FIXME: can this heuristic be improved: we declare first context always valid, and next ones
 246          * if it has been modified by the call to StackWalk...
 247          */
 248         dbg_curr_thread->frames[nf].is_ctx_valid =
 249             (nf == 0 ||
 250              (dbg_curr_thread->frames[nf - 1].is_ctx_valid &&
 251               memcmp(&dbg_curr_thread->frames[nf - 1].context, &ctx, sizeof(ctx))));
 252         prevctx = ctx;
 253         nf++;
 254         /* we've probably gotten ourselves into an infinite loop so bail */
 255         if (nf > 200) break;
 256     }
 257     dbg_curr_thread->curr_frame = -1;
 258     dbg_curr_thread->num_frames = nf;
 259     stack_set_frame_internal(0);
 260     return nf;
 261 }
 262
 263 struct sym_enum
 264 {
 265     DWORD_PTR   frame;
 266     BOOL        first;
 267 };
 268
 269 static BOOL WINAPI sym_enum_cb(PSYMBOL_INFO sym_info, ULONG size, PVOID user)
 270 {
 271     struct sym_enum*    se = user;
 272
 273     if (sym_info->Flags & SYMFLAG_PARAMETER)
 274     {
 275         if (!se->first) dbg_printf(", "); else se->first = FALSE;
 276         symbol_print_local(sym_info, se->frame, FALSE);
 277     }
 278     return TRUE;
 279 }
 280
 281 static void stack_print_addr_and_args(int nf)
 282 {
 283     char                        buffer[sizeof(SYMBOL_INFO) + 256];
 284     SYMBOL_INFO*                si = (SYMBOL_INFO*)buffer;
 285     IMAGEHLP_STACK_FRAME        ihsf;
 286     IMAGEHLP_LINE64             il;
 287     IMAGEHLP_MODULE             im;
 288     DWORD64                     disp64;
 289
 290     print_bare_address(&dbg_curr_thread->frames[nf].addr_pc);
 291
 292     stack_get_frame(nf, &ihsf);
 293
 294     /* grab module where symbol is. If we don't have a module, we cannot print more */
 295     im.SizeOfStruct = sizeof(im);
 296     if (!SymGetModuleInfo(dbg_curr_process->handle, ihsf.InstructionOffset, &im))
 297         return;
 298
 299     si->SizeOfStruct = sizeof(*si);
 300     si->MaxNameLen   = 256;
 301     if (SymFromAddr(dbg_curr_process->handle, ihsf.InstructionOffset, &disp64, si))
 302     {
 303         struct sym_enum se;
 304         DWORD           disp;
 305
 306         dbg_printf(" %s", si->Name);
 307         if (disp64) dbg_printf("+0x%lx", (DWORD_PTR)disp64);
 308
 309         SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
 310         se.first = TRUE;
 311         se.frame = ihsf.FrameOffset;
 312         dbg_printf("(");
 313         SymEnumSymbols(dbg_curr_process->handle, 0, NULL, sym_enum_cb, &se);
 314         dbg_printf(")");
 315
 316         il.SizeOfStruct = sizeof(il);
 317         if (SymGetLineFromAddr64(dbg_curr_process->handle,
 318                                  ihsf.InstructionOffset, &disp, &il))
 319             dbg_printf(" [%s:%u]", il.FileName, il.LineNumber);
 320         dbg_printf(" in %s", im.ModuleName);
 321     }
 322     else dbg_printf(" in %s (+0x%lx)",
 323                     im.ModuleName, (DWORD_PTR)(ihsf.InstructionOffset - im.BaseOfImage));
 324 }
 325
 326 /******************************************************************
 327  *              backtrace
 328  *
 329  * Do a backtrace on the current thread
 330  */
 331 static void backtrace(void)
 332 {
 333     unsigned                    cf = dbg_curr_thread->curr_frame;
 334     IMAGEHLP_STACK_FRAME        ihsf;
 335
 336     dbg_printf("Backtrace:\n");
 337     for (dbg_curr_thread->curr_frame = 0;
 338          dbg_curr_thread->curr_frame < dbg_curr_thread->num_frames;
 339          dbg_curr_thread->curr_frame++)
 340     {
 341         dbg_printf("%s%d ",
 342                    (cf == dbg_curr_thread->curr_frame ? "=>" : "  "),
 343                    dbg_curr_thread->curr_frame);
 344         stack_print_addr_and_args(dbg_curr_thread->curr_frame);
 345         dbg_printf(" (");
 346         print_bare_address(&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].addr_frame);
 347         dbg_printf(")\n");
 348     }
 349     /* reset context to current stack frame */
 350     dbg_curr_thread->curr_frame = cf;
 351     if (!dbg_curr_thread->frames) return;
 352     stack_get_frame(dbg_curr_thread->curr_frame, &ihsf);
 353     SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
 354 }
 355
 356 /******************************************************************
 357  *              backtrace_tid
 358  *
 359  * Do a backtrace on a thread from its process and its identifier
 360  * (preserves current thread and context information)
 361  */
 362 static void backtrace_tid(struct dbg_process* pcs, DWORD tid)
 363 {
 364     struct dbg_thread*  thread = dbg_curr_thread;
 365
 366     if (!(dbg_curr_thread = dbg_get_thread(pcs, tid)))
 367         dbg_printf("Unknown thread id (%04x) in process (%04x)\n", tid, pcs->pid);
 368     else
 369     {
 370         CONTEXT context;
 371
 372         dbg_curr_tid = dbg_curr_thread->tid;
 373         memset(&context, 0, sizeof(context));
 374         context.ContextFlags = CONTEXT_FULL;
 375         if (SuspendThread(dbg_curr_thread->handle) != -1)
 376         {
 377             if (!GetThreadContext(dbg_curr_thread->handle, &context))
 378             {
 379                 dbg_printf("Can't get context for thread %04x in current process\n",
 380                            tid);
 381             }
 382             else
 383             {
 384                 stack_fetch_frames(&context);
 385                 backtrace();
 386             }
 387             ResumeThread(dbg_curr_thread->handle);
 388         }
 389         else dbg_printf("Can't suspend thread %04x in current process\n", tid);
 390     }
 391     dbg_curr_thread = thread;
 392     dbg_curr_tid = thread ? thread->tid : 0;
 393 }
 394
 395 /******************************************************************
 396  *              backtrace_all
 397  *
 398  * Do a backtrace on every running thread in the system (except the debugger)
 399  * (preserves current process information)
 400  */
 401 static void backtrace_all(void)
 402 {
 403     struct dbg_process* process = dbg_curr_process;
 404     struct dbg_thread*  thread = dbg_curr_thread;
 405     CONTEXT             ctx = dbg_context;
 406     DWORD               cpid = dbg_curr_pid;
 407     THREADENTRY32       entry;
 408     HANDLE              snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
 409
 410     if (snapshot == INVALID_HANDLE_VALUE)
 411     {
 412         dbg_printf("Unable to create toolhelp snapshot\n");
 413         return;
 414     }
 415
 416     entry.dwSize = sizeof(entry);
 417     if (Thread32First(snapshot, &entry))
 418     {
 419         do
 420         {
 421             if (entry.th32OwnerProcessID == GetCurrentProcessId()) continue;
 422             if (dbg_curr_process && dbg_curr_pid != entry.th32OwnerProcessID &&
 423                 cpid != dbg_curr_pid)
 424                 dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 425
 426             if (entry.th32OwnerProcessID == cpid)
 427             {
 428                 dbg_curr_process = process;
 429                 dbg_curr_pid = cpid;
 430             }
 431             else if (entry.th32OwnerProcessID != dbg_curr_pid)
 432             {
 433                 if (!dbg_attach_debuggee(entry.th32OwnerProcessID, FALSE))
 434                 {
 435                     dbg_printf("\nwarning: could not attach to %04x\n",
 436                                entry.th32OwnerProcessID);
 437                     continue;
 438                 }
 439                 dbg_curr_pid = dbg_curr_process->pid;
 440                 dbg_active_wait_for_first_exception();
 441             }
 442
 443             dbg_printf("\nBacktracing for thread %04x in process %04lx (%s):\n",
 444                        entry.th32ThreadID, dbg_curr_pid,
 445                        dbg_W2A(dbg_curr_process->imageName, -1));
 446             backtrace_tid(dbg_curr_process, entry.th32ThreadID);
 447         }
 448         while (Thread32Next(snapshot, &entry));
 449
 450         if (dbg_curr_process && cpid != dbg_curr_pid)
 451             dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 452     }
 453     CloseHandle(snapshot);
 454     dbg_curr_process = process;
 455     dbg_curr_pid = cpid;
 456     dbg_curr_thread = thread;
 457     dbg_curr_tid = thread ? thread->tid : 0;
 458     dbg_context = ctx;
 459 }
 460
 461 void stack_backtrace(DWORD tid)
 462 {
 463     /* backtrace every thread in every process except the debugger itself,
 464      * invoking via "bt all"
 465      */
 466     if (tid == -1) return backtrace_all();
 467
 468     if (!dbg_curr_process)
 469     {
 470         dbg_printf("You must be attached to a process to run this command.\n");
 471         return;
 472     }
 473
 474     if (tid == dbg_curr_tid)
 475     {
 476         backtrace();
 477     }
 478     else
 479     {
 480         backtrace_tid(dbg_curr_process, tid);
 481     }
 482 }