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. If len <= 0, a default length is used.
  37  */
  38 void stack_info(int len)
  39 {
  40     struct dbg_lvalue lvalue;
  41
  42     if(len <= 0)
  43         len = 24;
  44
  45     lvalue.cookie = 0;
  46     lvalue.type.id = dbg_itype_segptr;
  47     lvalue.type.module = 0;
  48
  49     /* FIXME: we assume stack grows the same way as on i386 */
  50     if (!memory_get_current_stack(&lvalue.addr))
  51         dbg_printf("Bad segment (%d)\n", lvalue.addr.Segment);
  52
  53     dbg_printf("Stack dump:\n");
  54     switch (lvalue.addr.Mode)
  55     {
  56     case AddrModeFlat: /* 32-bit or 64-bit mode */
  57         memory_examine(&lvalue, len, 'a');
  58         break;
  59     case AddrMode1632: /* 32-bit mode */
  60         memory_examine(&lvalue, len, 'x');
  61         break;
  62     case AddrModeReal:  /* 16-bit mode */
  63     case AddrMode1616:
  64         memory_examine(&lvalue, len, 'w');
  65         break;
  66     }
  67 }
  68
  69 static BOOL stack_set_frame_internal(int newframe)
  70 {
  71     if (newframe >= dbg_curr_thread->num_frames)
  72         newframe = dbg_curr_thread->num_frames - 1;
  73     if (newframe < 0)
  74         newframe = 0;
  75
  76     if (dbg_curr_thread->curr_frame != newframe)
  77     {
  78         IMAGEHLP_STACK_FRAME    ihsf;
  79
  80         dbg_curr_thread->curr_frame = newframe;
  81         stack_get_current_frame(&ihsf);
  82         SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
  83     }
  84     return TRUE;
  85 }
  86
  87 static BOOL stack_get_frame(int nf, IMAGEHLP_STACK_FRAME* ihsf)
  88 {
  89     memset(ihsf, 0, sizeof(*ihsf));
  90     ihsf->InstructionOffset = dbg_curr_thread->frames[nf].linear_pc;
  91     /* if we're not the first frame, InstructionOffset is the return address
  92      * after the call instruction (at least on most processors I know of).
  93      * However, there are cases where this address is outside of the current function.
  94      * This happens when the called function is marked <NO RETURN>, in which
  95      * case the compiler can omit the epilog (gcc 4 does it)
  96      * Therefore, we decrement InstructionOffset in order to ensure that
  97      * the considered address is really inside the current function.
  98      */
  99     if (nf) ihsf->InstructionOffset--;
 100     ihsf->FrameOffset = dbg_curr_thread->frames[nf].linear_frame;
 101     ihsf->StackOffset = dbg_curr_thread->frames[nf].linear_stack;
 102     return TRUE;
 103 }
 104
 105 BOOL stack_get_current_frame(IMAGEHLP_STACK_FRAME* ihsf)
 106 {
 107     /*
 108      * If we don't have a valid backtrace, then just return.
 109      */
 110     if (dbg_curr_thread->frames == NULL) return FALSE;
 111     return stack_get_frame(dbg_curr_thread->curr_frame, ihsf);
 112 }
 113
 114 BOOL stack_get_register_current_frame(unsigned regno, DWORD_PTR** pval)
 115 {
 116     enum be_cpu_addr            kind;
 117
 118     if (dbg_curr_thread->frames == NULL) return FALSE;
 119
 120     if (!be_cpu->get_register_info(regno, &kind)) return FALSE;
 121
 122     switch (kind)
 123     {
 124     case be_cpu_addr_pc:
 125         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_pc;
 126         break;
 127     case be_cpu_addr_stack:
 128         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_stack;
 129         break;
 130     case be_cpu_addr_frame:
 131         *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_frame;
 132         break;
 133     }
 134     return TRUE;
 135 }
 136
 137 BOOL stack_get_register_frame(const struct dbg_internal_var* div, DWORD_PTR** pval)
 138 {
 139     if (dbg_curr_thread->frames == NULL) return FALSE;
 140     if (dbg_curr_thread->frames[dbg_curr_thread->curr_frame].is_ctx_valid)
 141         *pval = (DWORD_PTR*)((char*)&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].context +
 142                              (DWORD_PTR)div->pval);
 143     else
 144     {
 145         enum be_cpu_addr        kind;
 146
 147         if (!be_cpu->get_register_info(div->val, &kind)) return FALSE;
 148
 149         /* reuse some known registers directly out of stackwalk details */
 150         switch (kind)
 151         {
 152         case be_cpu_addr_pc:
 153             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_pc;
 154             break;
 155         case be_cpu_addr_stack:
 156             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_stack;
 157             break;
 158         case be_cpu_addr_frame:
 159             *pval = &dbg_curr_thread->frames[dbg_curr_thread->curr_frame].linear_frame;
 160             break;
 161         }
 162     }
 163     return TRUE;
 164 }
 165
 166 BOOL stack_set_frame(int newframe)
 167 {
 168     ADDRESS64   addr;
 169     if (!stack_set_frame_internal(newframe)) return FALSE;
 170     addr.Mode = AddrModeFlat;
 171     addr.Offset = (DWORD_PTR)memory_to_linear_addr(&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].addr_pc);
 172     source_list_from_addr(&addr, 0);
 173     return TRUE;
 174 }
 175
 176 /******************************************************************
 177  *              stack_get_current_symbol
 178  *
 179  * Retrieves the symbol information for the current frame element
 180  */
 181 BOOL stack_get_current_symbol(SYMBOL_INFO* symbol)
 182 {
 183     IMAGEHLP_STACK_FRAME        ihsf;
 184     DWORD64                     disp;
 185
 186     if (!stack_get_current_frame(&ihsf)) return FALSE;
 187     return SymFromAddr(dbg_curr_process->handle, ihsf.InstructionOffset,
 188                        &disp, symbol);
 189 }
 190
 191 static BOOL CALLBACK stack_read_mem(HANDLE hProc, DWORD64 addr,
 192                                     PVOID buffer, DWORD size, PDWORD written)
 193 {
 194     SIZE_T sz;
 195     BOOL ret;
 196
 197     struct dbg_process* pcs = dbg_get_process_h(hProc);
 198     if (!pcs) return FALSE;
 199     ret = pcs->process_io->read(hProc, (const void*)(DWORD_PTR)addr, buffer,
 200                                 size, &sz);
 201     if (written != NULL) *written = sz;
 202     return ret;
 203 }
 204
 205 /******************************************************************
 206  *              stack_fetch_frames
 207  *
 208  * Do a backtrace on the current thread
 209  */
 210 unsigned stack_fetch_frames(const CONTEXT* _ctx)
 211 {
 212     STACKFRAME64 sf;
 213     unsigned     nf = 0;
 214     /* as native stackwalk can modify the context passed to it, simply copy
 215      * it to avoid any damage
 216      */
 217     CONTEXT      ctx = *_ctx, prevctx = ctx;
 218
 219     HeapFree(GetProcessHeap(), 0, dbg_curr_thread->frames);
 220     dbg_curr_thread->frames = NULL;
 221
 222     memset(&sf, 0, sizeof(sf));
 223     memory_get_current_frame(&sf.AddrFrame);
 224     memory_get_current_pc(&sf.AddrPC);
 225     memory_get_current_stack(&sf.AddrStack);
 226
 227     /* don't confuse StackWalk by passing in inconsistent addresses */
 228     if ((sf.AddrPC.Mode == AddrModeFlat) && (sf.AddrFrame.Mode != AddrModeFlat))
 229     {
 230         sf.AddrFrame.Offset = (ULONG_PTR)memory_to_linear_addr(&sf.AddrFrame);
 231         sf.AddrFrame.Mode = AddrModeFlat;
 232     }
 233
 234     while (StackWalk64(be_cpu->machine, dbg_curr_process->handle,
 235                        dbg_curr_thread->handle, &sf, &ctx, stack_read_mem,
 236                        SymFunctionTableAccess64, SymGetModuleBase64, NULL))
 237     {
 238         dbg_curr_thread->frames = dbg_heap_realloc(dbg_curr_thread->frames,
 239                                                    (nf + 1) * sizeof(dbg_curr_thread->frames[0]));
 240
 241         dbg_curr_thread->frames[nf].addr_pc      = sf.AddrPC;
 242         dbg_curr_thread->frames[nf].linear_pc    = (DWORD_PTR)memory_to_linear_addr(&sf.AddrPC);
 243         dbg_curr_thread->frames[nf].addr_frame   = sf.AddrFrame;
 244         dbg_curr_thread->frames[nf].linear_frame = (DWORD_PTR)memory_to_linear_addr(&sf.AddrFrame);
 245         dbg_curr_thread->frames[nf].addr_stack   = sf.AddrStack;
 246         dbg_curr_thread->frames[nf].linear_stack = (DWORD_PTR)memory_to_linear_addr(&sf.AddrStack);
 247         dbg_curr_thread->frames[nf].context      = prevctx;
 248         /* FIXME: can this heuristic be improved: we declare first context always valid, and next ones
 249          * if it has been modified by the call to StackWalk...
 250          */
 251         dbg_curr_thread->frames[nf].is_ctx_valid =
 252             (nf == 0 ||
 253              (dbg_curr_thread->frames[nf - 1].is_ctx_valid &&
 254               memcmp(&dbg_curr_thread->frames[nf - 1].context, &ctx, sizeof(ctx))));
 255         prevctx = ctx;
 256         nf++;
 257         /* we've probably gotten ourselves into an infinite loop so bail */
 258         if (nf > 200) break;
 259     }
 260     dbg_curr_thread->curr_frame = -1;
 261     dbg_curr_thread->num_frames = nf;
 262     stack_set_frame_internal(0);
 263     return nf;
 264 }
 265
 266 struct sym_enum
 267 {
 268     DWORD_PTR   frame;
 269     BOOL        first;
 270 };
 271
 272 static BOOL WINAPI sym_enum_cb(PSYMBOL_INFO sym_info, ULONG size, PVOID user)
 273 {
 274     struct sym_enum*    se = user;
 275
 276     if (sym_info->Flags & SYMFLAG_PARAMETER)
 277     {
 278         if (!se->first) dbg_printf(", "); else se->first = FALSE;
 279         symbol_print_local(sym_info, se->frame, FALSE);
 280     }
 281     return TRUE;
 282 }
 283
 284 static void stack_print_addr_and_args(int nf)
 285 {
 286     char                        buffer[sizeof(SYMBOL_INFO) + 256];
 287     SYMBOL_INFO*                si = (SYMBOL_INFO*)buffer;
 288     IMAGEHLP_STACK_FRAME        ihsf;
 289     IMAGEHLP_LINE64             il;
 290     IMAGEHLP_MODULE             im;
 291     DWORD64                     disp64;
 292
 293     print_bare_address(&dbg_curr_thread->frames[nf].addr_pc);
 294
 295     stack_get_frame(nf, &ihsf);
 296
 297     /* grab module where symbol is. If we don't have a module, we cannot print more */
 298     im.SizeOfStruct = sizeof(im);
 299     if (!SymGetModuleInfo(dbg_curr_process->handle, ihsf.InstructionOffset, &im))
 300         return;
 301
 302     si->SizeOfStruct = sizeof(*si);
 303     si->MaxNameLen   = 256;
 304     if (SymFromAddr(dbg_curr_process->handle, ihsf.InstructionOffset, &disp64, si))
 305     {
 306         struct sym_enum se;
 307         DWORD           disp;
 308
 309         dbg_printf(" %s", si->Name);
 310         if (disp64) dbg_printf("+0x%lx", (DWORD_PTR)disp64);
 311
 312         SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
 313         se.first = TRUE;
 314         se.frame = ihsf.FrameOffset;
 315         dbg_printf("(");
 316         SymEnumSymbols(dbg_curr_process->handle, 0, NULL, sym_enum_cb, &se);
 317         dbg_printf(")");
 318
 319         il.SizeOfStruct = sizeof(il);
 320         if (SymGetLineFromAddr64(dbg_curr_process->handle,
 321                                  ihsf.InstructionOffset, &disp, &il))
 322             dbg_printf(" [%s:%u]", il.FileName, il.LineNumber);
 323         dbg_printf(" in %s", im.ModuleName);
 324     }
 325     else dbg_printf(" in %s (+0x%lx)",
 326                     im.ModuleName, (DWORD_PTR)(ihsf.InstructionOffset - im.BaseOfImage));
 327 }
 328
 329 /******************************************************************
 330  *              backtrace
 331  *
 332  * Do a backtrace on the current thread
 333  */
 334 static void backtrace(void)
 335 {
 336     unsigned                    cf = dbg_curr_thread->curr_frame;
 337     IMAGEHLP_STACK_FRAME        ihsf;
 338
 339     dbg_printf("Backtrace:\n");
 340     for (dbg_curr_thread->curr_frame = 0;
 341          dbg_curr_thread->curr_frame < dbg_curr_thread->num_frames;
 342          dbg_curr_thread->curr_frame++)
 343     {
 344         dbg_printf("%s%d ",
 345                    (cf == dbg_curr_thread->curr_frame ? "=>" : "  "),
 346                    dbg_curr_thread->curr_frame);
 347         stack_print_addr_and_args(dbg_curr_thread->curr_frame);
 348         dbg_printf(" (");
 349         print_bare_address(&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].addr_frame);
 350         dbg_printf(")\n");
 351     }
 352     /* reset context to current stack frame */
 353     dbg_curr_thread->curr_frame = cf;
 354     if (!dbg_curr_thread->frames) return;
 355     stack_get_frame(dbg_curr_thread->curr_frame, &ihsf);
 356     SymSetContext(dbg_curr_process->handle, &ihsf, NULL);
 357 }
 358
 359 /******************************************************************
 360  *              backtrace_tid
 361  *
 362  * Do a backtrace on a thread from its process and its identifier
 363  * (preserves current thread and context information)
 364  */
 365 static void backtrace_tid(struct dbg_process* pcs, DWORD tid)
 366 {
 367     struct dbg_thread*  thread = dbg_curr_thread;
 368
 369     if (!(dbg_curr_thread = dbg_get_thread(pcs, tid)))
 370         dbg_printf("Unknown thread id (%04x) in process (%04x)\n", tid, pcs->pid);
 371     else
 372     {
 373         CONTEXT context;
 374
 375         dbg_curr_tid = dbg_curr_thread->tid;
 376         memset(&context, 0, sizeof(context));
 377         context.ContextFlags = CONTEXT_FULL;
 378         if (SuspendThread(dbg_curr_thread->handle) != -1)
 379         {
 380             if (!GetThreadContext(dbg_curr_thread->handle, &context))
 381             {
 382                 dbg_printf("Can't get context for thread %04x in current process\n",
 383                            tid);
 384             }
 385             else
 386             {
 387                 stack_fetch_frames(&context);
 388                 backtrace();
 389             }
 390             ResumeThread(dbg_curr_thread->handle);
 391         }
 392         else dbg_printf("Can't suspend thread %04x in current process\n", tid);
 393     }
 394     dbg_curr_thread = thread;
 395     dbg_curr_tid = thread ? thread->tid : 0;
 396 }
 397
 398 /******************************************************************
 399  *              backtrace_all
 400  *
 401  * Do a backtrace on every running thread in the system (except the debugger)
 402  * (preserves current process information)
 403  */
 404 static void backtrace_all(void)
 405 {
 406     struct dbg_process* process = dbg_curr_process;
 407     struct dbg_thread*  thread = dbg_curr_thread;
 408     CONTEXT             ctx = dbg_context;
 409     DWORD               cpid = dbg_curr_pid;
 410     THREADENTRY32       entry;
 411     HANDLE              snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
 412
 413     if (snapshot == INVALID_HANDLE_VALUE)
 414     {
 415         dbg_printf("Unable to create toolhelp snapshot\n");
 416         return;
 417     }
 418
 419     entry.dwSize = sizeof(entry);
 420     if (Thread32First(snapshot, &entry))
 421     {
 422         do
 423         {
 424             if (entry.th32OwnerProcessID == GetCurrentProcessId()) continue;
 425             if (dbg_curr_process && dbg_curr_pid != entry.th32OwnerProcessID &&
 426                 cpid != dbg_curr_pid)
 427                 dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 428
 429             if (entry.th32OwnerProcessID == cpid)
 430             {
 431                 dbg_curr_process = process;
 432                 dbg_curr_pid = cpid;
 433             }
 434             else if (entry.th32OwnerProcessID != dbg_curr_pid)
 435             {
 436                 if (!dbg_attach_debuggee(entry.th32OwnerProcessID, FALSE))
 437                 {
 438                     dbg_printf("\nwarning: could not attach to %04x\n",
 439                                entry.th32OwnerProcessID);
 440                     continue;
 441                 }
 442                 dbg_curr_pid = dbg_curr_process->pid;
 443                 dbg_active_wait_for_first_exception();
 444             }
 445
 446             dbg_printf("\nBacktracing for thread %04x in process %04lx (%s):\n",
 447                        entry.th32ThreadID, dbg_curr_pid,
 448                        dbg_W2A(dbg_curr_process->imageName, -1));
 449             backtrace_tid(dbg_curr_process, entry.th32ThreadID);
 450         }
 451         while (Thread32Next(snapshot, &entry));
 452
 453         if (dbg_curr_process && cpid != dbg_curr_pid)
 454             dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 455     }
 456     CloseHandle(snapshot);
 457     dbg_curr_process = process;
 458     dbg_curr_pid = cpid;
 459     dbg_curr_thread = thread;
 460     dbg_curr_tid = thread ? thread->tid : 0;
 461     dbg_context = ctx;
 462 }
 463
 464 void stack_backtrace(DWORD tid)
 465 {
 466     /* backtrace every thread in every process except the debugger itself,
 467      * invoking via "bt all"
 468      */
 469     if (tid == -1) return backtrace_all();
 470
 471     if (!dbg_curr_process)
 472     {
 473         dbg_printf("You must be attached to a process to run this command.\n");
 474         return;
 475     }
 476
 477     if (tid == dbg_curr_tid)
 478     {
 479         backtrace();
 480     }
 481     else
 482     {
 483         backtrace_tid(dbg_curr_process, tid);
 484     }
 485 }