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 <stdlib.h>
  24 #include <stdio.h>
  25
  26 #include "debugger.h"
  27 #include "winbase.h"
  28 #include "wine/winbase16.h"
  29 #include "tlhelp32.h"
  30
  31 /***********************************************************************
  32  *           stack_info
  33  *
  34  * Dump the top of the stack. If len <= 0, a default length is used.
  35  */
  36 void stack_info(int len)
  37 {
  38     struct dbg_lvalue lvalue;
  39
  40     if(len <= 0)
  41         len = 24;
  42     init_lvalue(&lvalue, TRUE, 0);
  43     lvalue.type.id = dbg_itype_segptr;
  44
  45     /* FIXME: we assume stack grows the same way as on i386 */
  46     if (!memory_get_current_stack(&lvalue.addr))
  47         dbg_printf("Bad segment (%d)\n", lvalue.addr.Segment);
  48
  49     dbg_printf("Stack dump:\n");
  50     switch (lvalue.addr.Mode)
  51     {
  52     case AddrModeFlat: /* 32-bit or 64-bit mode */
  53         memory_examine(&lvalue, len, 'a');
  54         break;
  55     case AddrMode1632: /* 32-bit mode */
  56         memory_examine(&lvalue, len, 'x');
  57         break;
  58     case AddrModeReal:  /* 16-bit mode */
  59     case AddrMode1616:
  60         memory_examine(&lvalue, len, 'w');
  61         break;
  62     }
  63 }
  64
  65 static BOOL stack_set_local_scope(void)
  66 {
  67     struct dbg_frame* frm = stack_get_thread_frame(dbg_curr_thread, dbg_curr_thread->curr_frame);
  68
  69     if (!frm) return FALSE;
  70     /* if we're not the first frame, linear_pc is the return address
  71      * after the call instruction (at least on most processors I know of).
  72      * However, there are cases where this address is outside of the
  73      * current function or inline site.
  74      * This happens when the called function is marked <NO RETURN>, in which
  75      * case the compiler can omit the epilog (gcc 4 does it).
  76      * This happens also for inline sites, where the epilog (of the inline
  77      * site) isn't present.
  78      * Therefore, we decrement linear_pc in order to ensure that
  79      * the considered address is really inside the current function or inline site.
  80      */
  81     return SymSetScopeFromInlineContext(dbg_curr_process->handle,
  82                                         (dbg_curr_thread->curr_frame) ? frm->linear_pc - 1 : frm->linear_pc,
  83                                         frm->inline_ctx);
  84 }
  85
  86 static BOOL stack_set_frame_internal(int newframe)
  87 {
  88     if (newframe >= dbg_curr_thread->num_frames)
  89         newframe = dbg_curr_thread->num_frames - 1;
  90     if (newframe < 0)
  91         newframe = 0;
  92
  93     if (dbg_curr_thread->curr_frame != newframe)
  94     {
  95         dbg_curr_thread->curr_frame = newframe;
  96         stack_set_local_scope();
  97     }
  98     return TRUE;
  99 }
 100
 101 BOOL stack_get_register_frame(const struct dbg_internal_var* div, struct dbg_lvalue* lvalue)
 102 {
 103     struct dbg_frame* currfrm = stack_get_curr_frame();
 104     if (currfrm == NULL) return FALSE;
 105     if (currfrm->is_ctx_valid)
 106         init_lvalue_in_debugger(lvalue, 0, div->typeid,
 107                                 (char*)&currfrm->context + (DWORD_PTR)div->pval);
 108     else
 109     {
 110         enum be_cpu_addr        kind;
 111         DWORD                   itype = ADDRSIZE == 4 ? dbg_itype_unsigned_long32 : dbg_itype_unsigned_long64;
 112
 113         if (!dbg_curr_process->be_cpu->get_register_info(div->val, &kind)) return FALSE;
 114
 115         /* reuse some known registers directly out of stackwalk details */
 116         switch (kind)
 117         {
 118         case be_cpu_addr_pc:
 119             init_lvalue_in_debugger(lvalue, 0, itype, &currfrm->linear_pc);
 120             break;
 121         case be_cpu_addr_stack:
 122             init_lvalue_in_debugger(lvalue, 0, itype, &currfrm->linear_stack);
 123             break;
 124         case be_cpu_addr_frame:
 125             init_lvalue_in_debugger(lvalue, 0, itype, &currfrm->linear_frame);
 126             break;
 127         }
 128     }
 129     return TRUE;
 130 }
 131
 132 BOOL stack_set_frame(int newframe)
 133 {
 134     ADDRESS64   addr;
 135     if (!stack_set_frame_internal(newframe)) return FALSE;
 136     addr.Mode = AddrModeFlat;
 137     addr.Offset = (DWORD_PTR)memory_to_linear_addr(&stack_get_curr_frame()->addr_pc);
 138     source_list_from_addr(&addr, 0);
 139     return TRUE;
 140 }
 141
 142 /******************************************************************
 143  *              stack_get_current_symbol
 144  *
 145  * Retrieves the symbol information for the current frame element
 146  */
 147 BOOL stack_get_current_symbol(SYMBOL_INFO* symbol)
 148 {
 149     DWORD64                     disp;
 150     struct dbg_frame*           frm = stack_get_curr_frame();
 151
 152     if (frm == NULL) return FALSE;
 153     return SymFromInlineContext(dbg_curr_process->handle, frm->linear_pc, frm->inline_ctx, &disp, symbol);
 154 }
 155
 156 static BOOL CALLBACK stack_read_mem(HANDLE hProc, DWORD64 addr,
 157                                     PVOID buffer, DWORD size, PDWORD written)
 158 {
 159     SIZE_T sz;
 160     BOOL ret;
 161
 162     struct dbg_process* pcs = dbg_get_process_h(hProc);
 163     if (!pcs) return FALSE;
 164     ret = pcs->process_io->read(hProc, (const void*)(DWORD_PTR)addr, buffer,
 165                                 size, &sz);
 166     if (written != NULL) *written = sz;
 167     return ret;
 168 }
 169
 170 /******************************************************************
 171  *              stack_fetch_frames
 172  *
 173  * Do a backtrace on the current thread
 174  */
 175 unsigned stack_fetch_frames(const dbg_ctx_t* _ctx)
 176 {
 177     STACKFRAME_EX sf;
 178     unsigned      nf = 0;
 179     /* as native stackwalk can modify the context passed to it, simply copy
 180      * it to avoid any damage
 181      */
 182     dbg_ctx_t     ctx = *_ctx;
 183     BOOL          ret;
 184
 185     free(dbg_curr_thread->frames);
 186     dbg_curr_thread->frames = NULL;
 187
 188     memset(&sf, 0, sizeof(sf));
 189     sf.StackFrameSize = sizeof(sf);
 190     dbg_curr_process->be_cpu->get_addr(dbg_curr_thread->handle, &ctx, be_cpu_addr_frame, &sf.AddrFrame);
 191     dbg_curr_process->be_cpu->get_addr(dbg_curr_thread->handle, &ctx, be_cpu_addr_pc, &sf.AddrPC);
 192     dbg_curr_process->be_cpu->get_addr(dbg_curr_thread->handle, &ctx, be_cpu_addr_stack, &sf.AddrStack);
 193     sf.InlineFrameContext = INLINE_FRAME_CONTEXT_INIT;
 194
 195     /* don't confuse StackWalk by passing in inconsistent addresses */
 196     if ((sf.AddrPC.Mode == AddrModeFlat) && (sf.AddrFrame.Mode != AddrModeFlat))
 197     {
 198         sf.AddrFrame.Offset = (ULONG_PTR)memory_to_linear_addr(&sf.AddrFrame);
 199         sf.AddrFrame.Mode = AddrModeFlat;
 200     }
 201
 202     while ((ret = StackWalkEx(dbg_curr_process->be_cpu->machine, dbg_curr_process->handle,
 203                               dbg_curr_thread->handle, &sf, &ctx, stack_read_mem,
 204                               SymFunctionTableAccess64, SymGetModuleBase64, NULL, SYM_STKWALK_DEFAULT)) ||
 205            nf == 0) /* we always register first frame information */
 206     {
 207         struct dbg_frame* new = realloc(dbg_curr_thread->frames,
 208                                         (nf + 1) * sizeof(dbg_curr_thread->frames[0]));
 209         if (!new) break;
 210         dbg_curr_thread->frames = new;
 211
 212         dbg_curr_thread->frames[nf].addr_pc      = sf.AddrPC;
 213         dbg_curr_thread->frames[nf].linear_pc    = (DWORD_PTR)memory_to_linear_addr(&sf.AddrPC);
 214         dbg_curr_thread->frames[nf].addr_frame   = sf.AddrFrame;
 215         dbg_curr_thread->frames[nf].linear_frame = (DWORD_PTR)memory_to_linear_addr(&sf.AddrFrame);
 216         dbg_curr_thread->frames[nf].addr_stack   = sf.AddrStack;
 217         dbg_curr_thread->frames[nf].linear_stack = (DWORD_PTR)memory_to_linear_addr(&sf.AddrStack);
 218         dbg_curr_thread->frames[nf].context      = ctx;
 219         dbg_curr_thread->frames[nf].inline_ctx   = sf.InlineFrameContext;
 220         /* FIXME: can this heuristic be improved: we declare first context always valid, and next ones
 221          * if it has been modified by the call to StackWalk...
 222          */
 223         dbg_curr_thread->frames[nf].is_ctx_valid =
 224             (nf == 0 ||
 225              (dbg_curr_thread->frames[nf - 1].is_ctx_valid &&
 226               memcmp(&dbg_curr_thread->frames[nf - 1].context, &ctx, sizeof(ctx))));
 227         nf++;
 228         /* bail if:
 229          * - we've (probably) gotten ourselves into an infinite loop,
 230          * - or StackWalk failed on first frame
 231          */
 232         if (nf > 200 || !ret) break;
 233     }
 234     dbg_curr_thread->curr_frame = -1;
 235     dbg_curr_thread->num_frames = nf;
 236     stack_set_frame_internal(0);
 237     return nf;
 238 }
 239
 240 struct sym_enum
 241 {
 242     DWORD_PTR   frame;
 243     BOOL        first;
 244 };
 245
 246 static BOOL WINAPI sym_enum_cb(PSYMBOL_INFO sym_info, ULONG size, PVOID user)
 247 {
 248     struct sym_enum*    se = user;
 249
 250     if (sym_info->Flags & SYMFLAG_PARAMETER)
 251     {
 252         if (!se->first) dbg_printf(", "); else se->first = FALSE;
 253         dbg_printf("%s=", sym_info->Name);
 254         symbol_print_localvalue(sym_info, se->frame, FALSE);
 255     }
 256     return TRUE;
 257 }
 258
 259 static void stack_print_addr_and_args(void)
 260 {
 261     char                        buffer[sizeof(SYMBOL_INFO) + 256];
 262     SYMBOL_INFO*                si = (SYMBOL_INFO*)buffer;
 263     IMAGEHLP_LINE64             il;
 264     IMAGEHLP_MODULE             im;
 265     DWORD64                     disp64;
 266     struct dbg_frame*           frm = stack_get_curr_frame();
 267
 268     if (!frm) return;
 269     print_bare_address(&frm->addr_pc);
 270
 271     /* grab module where symbol is. If we don't have a module, we cannot print more */
 272     im.SizeOfStruct = sizeof(im);
 273     if (!SymGetModuleInfo(dbg_curr_process->handle, frm->linear_pc, &im))
 274         return;
 275
 276     si->SizeOfStruct = sizeof(*si);
 277     si->MaxNameLen   = 256;
 278     if (SymFromInlineContext(dbg_curr_process->handle, frm->linear_pc, frm->inline_ctx, &disp64, si))
 279     {
 280         struct sym_enum se;
 281         DWORD           disp;
 282
 283         dbg_printf(" %s", si->Name);
 284         if (disp64) dbg_printf("+0x%I64x", disp64);
 285
 286         stack_set_local_scope();
 287         se.first = TRUE;
 288         se.frame = frm->linear_frame;
 289         dbg_printf("(");
 290         SymEnumSymbols(dbg_curr_process->handle, 0, NULL, sym_enum_cb, &se);
 291         dbg_printf(")");
 292
 293         il.SizeOfStruct = sizeof(il);
 294         if (SymGetLineFromInlineContext(dbg_curr_process->handle, frm->linear_pc, frm->inline_ctx,
 295                                         0, &disp, &il))
 296             dbg_printf(" [%s:%lu]", il.FileName, il.LineNumber);
 297         dbg_printf(" in %s", im.ModuleName);
 298     }
 299     else dbg_printf(" in %s (+0x%Ix)", im.ModuleName, frm->linear_pc - (DWORD_PTR)im.BaseOfImage);
 300 }
 301
 302 /******************************************************************
 303  *              backtrace
 304  *
 305  * Do a backtrace on the current thread
 306  */
 307 static void backtrace(void)
 308 {
 309     unsigned                    cf = dbg_curr_thread->curr_frame;
 310
 311     dbg_printf("Backtrace:\n");
 312     for (dbg_curr_thread->curr_frame = 0;
 313          dbg_curr_thread->curr_frame < dbg_curr_thread->num_frames;
 314          dbg_curr_thread->curr_frame++)
 315     {
 316         dbg_printf("%s%d ",
 317                    (cf == dbg_curr_thread->curr_frame ? "=>" : "  "),
 318                    dbg_curr_thread->curr_frame);
 319         stack_print_addr_and_args();
 320         dbg_printf(" (");
 321         print_bare_address(&dbg_curr_thread->frames[dbg_curr_thread->curr_frame].addr_frame);
 322         dbg_printf(")\n");
 323     }
 324     /* reset context to current stack frame */
 325     dbg_curr_thread->curr_frame = cf;
 326     if (!dbg_curr_thread->frames) return;
 327     stack_set_local_scope();
 328 }
 329
 330 /******************************************************************
 331  *              backtrace_tid
 332  *
 333  * Do a backtrace on a thread from its process and its identifier
 334  * (preserves current thread and context information)
 335  */
 336 static void backtrace_tid(struct dbg_process* pcs, DWORD tid)
 337 {
 338     struct dbg_thread*  thread = dbg_curr_thread;
 339
 340     if (!(dbg_curr_thread = dbg_get_thread(pcs, tid)))
 341         dbg_printf("Unknown thread id (%04lx) in process (%04lx)\n", tid, pcs->pid);
 342     else
 343     {
 344         dbg_ctx_t ctx = {{0}};
 345
 346         dbg_curr_tid = dbg_curr_thread->tid;
 347         if (SuspendThread(dbg_curr_thread->handle) != -1)
 348         {
 349             if (!pcs->be_cpu->get_context(dbg_curr_thread->handle, &ctx))
 350             {
 351                 dbg_printf("Can't get context for thread %04lx in current process\n",
 352                            tid);
 353             }
 354             else
 355             {
 356                 stack_fetch_frames(&ctx);
 357                 backtrace();
 358             }
 359             ResumeThread(dbg_curr_thread->handle);
 360         }
 361         else dbg_printf("Can't suspend thread %04lx in current process\n", tid);
 362     }
 363     dbg_curr_thread = thread;
 364     dbg_curr_tid = thread ? thread->tid : 0;
 365 }
 366
 367 /******************************************************************
 368  *              backtrace_all
 369  *
 370  * Do a backtrace on every running thread in the system (except the debugger)
 371  * (preserves current process information)
 372  */
 373 static void backtrace_all(void)
 374 {
 375     struct dbg_process* process = dbg_curr_process;
 376     struct dbg_thread*  thread = dbg_curr_thread;
 377     dbg_ctx_t ctx = dbg_context;
 378     DWORD               cpid = dbg_curr_pid;
 379     THREADENTRY32       entry;
 380     HANDLE              snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
 381
 382     if (snapshot == INVALID_HANDLE_VALUE)
 383     {
 384         dbg_printf("Unable to create toolhelp snapshot\n");
 385         return;
 386     }
 387
 388     entry.dwSize = sizeof(entry);
 389     if (Thread32First(snapshot, &entry))
 390     {
 391         do
 392         {
 393             if (entry.th32OwnerProcessID == GetCurrentProcessId()) continue;
 394             if (dbg_curr_process && dbg_curr_pid != entry.th32OwnerProcessID &&
 395                 cpid != dbg_curr_pid)
 396                 dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 397
 398             if (entry.th32OwnerProcessID == cpid)
 399             {
 400                 dbg_curr_process = process;
 401                 dbg_curr_pid = cpid;
 402             }
 403             else if (entry.th32OwnerProcessID != dbg_curr_pid)
 404             {
 405                 if (!dbg_attach_debuggee(entry.th32OwnerProcessID))
 406                 {
 407                     dbg_printf("\nwarning: could not attach to %04lx\n",
 408                                entry.th32OwnerProcessID);
 409                     continue;
 410                 }
 411                 dbg_curr_pid = dbg_curr_process->pid;
 412                 dbg_active_wait_for_first_exception();
 413             }
 414
 415             dbg_printf("\nBacktracing for thread %04lx in process %04lx (%ls):\n",
 416                        entry.th32ThreadID, dbg_curr_pid, dbg_curr_process->imageName);
 417             backtrace_tid(dbg_curr_process, entry.th32ThreadID);
 418         }
 419         while (Thread32Next(snapshot, &entry));
 420
 421         if (dbg_curr_process && cpid != dbg_curr_pid)
 422             dbg_curr_process->process_io->close_process(dbg_curr_process, FALSE);
 423     }
 424     CloseHandle(snapshot);
 425     dbg_curr_process = process;
 426     dbg_curr_pid = cpid;
 427     dbg_curr_thread = thread;
 428     dbg_curr_tid = thread ? thread->tid : 0;
 429     dbg_context = ctx;
 430 }
 431
 432 void stack_backtrace(DWORD tid)
 433 {
 434     /* backtrace every thread in every process except the debugger itself,
 435      * invoking via "bt all"
 436      */
 437     if (tid == -1)
 438     {
 439         backtrace_all();
 440         return;
 441     }
 442
 443     if (!dbg_curr_process)
 444     {
 445         dbg_printf("You must be attached to a process to run this command.\n");
 446         return;
 447     }
 448
 449     if (tid == dbg_curr_tid)
 450     {
 451         backtrace();
 452     }
 453     else
 454     {
 455         backtrace_tid(dbg_curr_process, tid);
 456     }
 457 }