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