dll/win32/dbghelp/cpu_i386.c

   1 /*
   2  * File cpu_i386.c
   3  *
   4  * Copyright (C) 2009-2009, Eric Pouech.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include <assert.h>
  22
  23 #include "ntstatus.h"
  24 #define WIN32_NO_STATUS
  25 #include "dbghelp_private.h"
  26 #include "wine/winbase16.h"
  27 #include "winternl.h"
  28 #include "wine/debug.h"
  29
  30 WINE_DEFAULT_DEBUG_CHANNEL(dbghelp);
  31
  32 #define STEP_FLAG 0x00000100 /* single step flag */
  33 #define V86_FLAG  0x00020000
  34
  35 #define IS_VM86_MODE(ctx) (ctx->EFlags & V86_FLAG)
  36
  37 #ifdef __i386__
  38 static ADDRESS_MODE get_selector_type(HANDLE hThread, const CONTEXT* ctx, WORD sel)
  39 {
  40     LDT_ENTRY   le;
  41
  42     if (IS_VM86_MODE(ctx)) return AddrModeReal;
  43     /* null or system selector */
  44     if (!(sel & 4) || ((sel >> 3) < 17)) return AddrModeFlat;
  45     if (hThread && GetThreadSelectorEntry(hThread, sel, &le))
  46         return le.HighWord.Bits.Default_Big ? AddrMode1632 : AddrMode1616;
  47     /* selector doesn't exist */
  48     return -1;
  49 }
  50
  51 static unsigned i386_build_addr(HANDLE hThread, const CONTEXT* ctx, ADDRESS64* addr,
  52                                 unsigned seg, unsigned long offset)
  53 {
  54     addr->Mode    = AddrModeFlat;
  55     addr->Segment = seg;
  56     addr->Offset  = offset;
  57     if (seg)
  58     {
  59         switch (addr->Mode = get_selector_type(hThread, ctx, seg))
  60         {
  61         case AddrModeReal:
  62         case AddrMode1616:
  63             addr->Offset &= 0xffff;
  64             break;
  65         case AddrModeFlat:
  66         case AddrMode1632:
  67             break;
  68         default:
  69             return FALSE;
  70         }
  71     }
  72     return TRUE;
  73 }
  74 #endif
  75
  76 static unsigned i386_get_addr(HANDLE hThread, const CONTEXT* ctx,
  77                               enum cpu_addr ca, ADDRESS64* addr)
  78 {
  79 #ifdef __i386__
  80     switch (ca)
  81     {
  82     case cpu_addr_pc:    return i386_build_addr(hThread, ctx, addr, ctx->SegCs, ctx->Eip);
  83     case cpu_addr_stack: return i386_build_addr(hThread, ctx, addr, ctx->SegSs, ctx->Esp);
  84     case cpu_addr_frame: return i386_build_addr(hThread, ctx, addr, ctx->SegSs, ctx->Ebp);
  85     }
  86 #endif
  87     return FALSE;
  88 }
  89
  90 enum st_mode {stm_start, stm_32bit, stm_16bit, stm_done};
  91
  92 /* indexes in Reserved array */
  93 #define __CurrentMode     0
  94 #define __CurrentSwitch   1
  95 #define __NextSwitch      2
  96
  97 #define curr_mode   (frame->Reserved[__CurrentMode])
  98 #define curr_switch (frame->Reserved[__CurrentSwitch])
  99 #define next_switch (frame->Reserved[__NextSwitch])
 100
 101 static BOOL i386_stack_walk(struct cpu_stack_walk* csw, LPSTACKFRAME64 frame)
 102 {
 103     STACK32FRAME        frame32;
 104     STACK16FRAME        frame16;
 105     char                ch;
 106     ADDRESS64           tmp;
 107     DWORD               p;
 108     WORD                val;
 109     BOOL                do_switch;
 110
 111     /* sanity check */
 112     if (curr_mode >= stm_done) return FALSE;
 113
 114     TRACE("Enter: PC=%s Frame=%s Return=%s Stack=%s Mode=%s cSwitch=%p nSwitch=%p\n",
 115           wine_dbgstr_addr(&frame->AddrPC),
 116           wine_dbgstr_addr(&frame->AddrFrame),
 117           wine_dbgstr_addr(&frame->AddrReturn),
 118           wine_dbgstr_addr(&frame->AddrStack),
 119           curr_mode == stm_start ? "start" : (curr_mode == stm_16bit ? "16bit" : "32bit"),
 120           (void*)(DWORD_PTR)curr_switch, (void*)(DWORD_PTR)next_switch);
 121
 122     if (curr_mode == stm_start)
 123     {
 124         THREAD_BASIC_INFORMATION info;
 125
 126         if ((frame->AddrPC.Mode == AddrModeFlat) &&
 127             (frame->AddrFrame.Mode != AddrModeFlat))
 128         {
 129             WARN("Bad AddrPC.Mode / AddrFrame.Mode combination\n");
 130             goto done_err;
 131         }
 132
 133         /* Init done */
 134         curr_mode = (frame->AddrPC.Mode == AddrModeFlat) ? stm_32bit : stm_16bit;
 135
 136         /* cur_switch holds address of WOW32Reserved field in TEB in debuggee
 137          * address space
 138          */
 139         if (NtQueryInformationThread(csw->hThread, ThreadBasicInformation, &info,
 140                                      sizeof(info), NULL) == STATUS_SUCCESS)
 141         {
 142             curr_switch = (unsigned long)info.TebBaseAddress + FIELD_OFFSET(TEB, WOW32Reserved);
 143             if (!sw_read_mem(csw, curr_switch, &p, sizeof(p)))
 144             {
 145                 WARN("Can't read TEB:WOW32Reserved\n");
 146                 goto done_err;
 147             }
 148             next_switch = p;
 149             if (!next_switch)  /* no 16-bit stack */
 150             {
 151                 curr_switch = 0;
 152             }
 153             else if (curr_mode == stm_16bit)
 154             {
 155                 if (!sw_read_mem(csw, next_switch, &frame32, sizeof(frame32)))
 156                 {
 157                     WARN("Bad stack frame %p\n", (void*)(DWORD_PTR)next_switch);
 158                     goto done_err;
 159                 }
 160                 curr_switch = (DWORD)frame32.frame16;
 161                 tmp.Mode    = AddrMode1616;
 162                 tmp.Segment = SELECTOROF(curr_switch);
 163                 tmp.Offset  = OFFSETOF(curr_switch);
 164                 if (!sw_read_mem(csw, sw_xlat_addr(csw, &tmp), &ch, sizeof(ch)))
 165                     curr_switch = 0xFFFFFFFF;
 166             }
 167             else
 168             {
 169                 tmp.Mode    = AddrMode1616;
 170                 tmp.Segment = SELECTOROF(next_switch);
 171                 tmp.Offset  = OFFSETOF(next_switch);
 172                 p = sw_xlat_addr(csw, &tmp);
 173                 if (!sw_read_mem(csw, p, &frame16, sizeof(frame16)))
 174                 {
 175                     WARN("Bad stack frame 0x%08x\n", p);
 176                     goto done_err;
 177                 }
 178                 curr_switch = (DWORD_PTR)frame16.frame32;
 179
 180                 if (!sw_read_mem(csw, curr_switch, &ch, sizeof(ch)))
 181                     curr_switch = 0xFFFFFFFF;
 182             }
 183         }
 184         else
 185             /* FIXME: this will allow to work when we're not attached to a live target,
 186              * but the 16 <=> 32 switch facility won't be available.
 187              */
 188             curr_switch = 0;
 189         frame->AddrReturn.Mode = frame->AddrStack.Mode = (curr_mode == stm_16bit) ? AddrMode1616 : AddrModeFlat;
 190         /* don't set up AddrStack on first call. Either the caller has set it up, or
 191          * we will get it in the next frame
 192          */
 193         memset(&frame->AddrBStore, 0, sizeof(frame->AddrBStore));
 194     }
 195     else
 196     {
 197         if (frame->AddrFrame.Offset == 0) goto done_err;
 198         if (frame->AddrFrame.Mode == AddrModeFlat)
 199         {
 200             assert(curr_mode == stm_32bit);
 201             do_switch = curr_switch && frame->AddrFrame.Offset >= curr_switch;
 202         }
 203         else
 204         {
 205             assert(curr_mode == stm_16bit);
 206             do_switch = curr_switch &&
 207                 frame->AddrFrame.Segment == SELECTOROF(curr_switch) &&
 208                 frame->AddrFrame.Offset >= OFFSETOF(curr_switch);
 209         }
 210
 211         if (do_switch)
 212         {
 213             if (curr_mode == stm_16bit)
 214             {
 215                 if (!sw_read_mem(csw, next_switch, &frame32, sizeof(frame32)))
 216                 {
 217                     WARN("Bad stack frame %p\n", (void*)(DWORD_PTR)next_switch);
 218                     goto done_err;
 219                 }
 220
 221                 frame->AddrPC.Mode        = AddrModeFlat;
 222                 frame->AddrPC.Segment     = 0;
 223                 frame->AddrPC.Offset      = frame32.retaddr;
 224                 frame->AddrFrame.Mode     = AddrModeFlat;
 225                 frame->AddrFrame.Segment  = 0;
 226                 frame->AddrFrame.Offset   = frame32.ebp;
 227
 228                 frame->AddrStack.Mode     = AddrModeFlat;
 229                 frame->AddrStack.Segment  = 0;
 230                 frame->AddrReturn.Mode    = AddrModeFlat;
 231                 frame->AddrReturn.Segment = 0;
 232
 233                 next_switch = curr_switch;
 234                 tmp.Mode    = AddrMode1616;
 235                 tmp.Segment = SELECTOROF(next_switch);
 236                 tmp.Offset  = OFFSETOF(next_switch);
 237                 p = sw_xlat_addr(csw, &tmp);
 238
 239                 if (!sw_read_mem(csw, p, &frame16, sizeof(frame16)))
 240                 {
 241                     WARN("Bad stack frame 0x%08x\n", p);
 242                     goto done_err;
 243                 }
 244                 curr_switch = (DWORD_PTR)frame16.frame32;
 245                 curr_mode = stm_32bit;
 246                 if (!sw_read_mem(csw, curr_switch, &ch, sizeof(ch)))
 247                     curr_switch = 0;
 248             }
 249             else
 250             {
 251                 tmp.Mode    = AddrMode1616;
 252                 tmp.Segment = SELECTOROF(next_switch);
 253                 tmp.Offset  = OFFSETOF(next_switch);
 254                 p = sw_xlat_addr(csw, &tmp);
 255
 256                 if (!sw_read_mem(csw, p, &frame16, sizeof(frame16)))
 257                 {
 258                     WARN("Bad stack frame 0x%08x\n", p);
 259                     goto done_err;
 260                 }
 261
 262                 TRACE("Got a 16 bit stack switch:"
 263                       "\n\tframe32: %08lx"
 264                       "\n\tedx:%08x ecx:%08x ebp:%08x"
 265                       "\n\tds:%04x es:%04x fs:%04x gs:%04x"
 266                       "\n\tcall_from_ip:%08x module_cs:%04x relay=%08x"
 267                       "\n\tentry_ip:%04x entry_point:%08x"
 268                       "\n\tbp:%04x ip:%04x cs:%04x\n",
 269                       (unsigned long)frame16.frame32,
 270                       frame16.edx, frame16.ecx, frame16.ebp,
 271                       frame16.ds, frame16.es, frame16.fs, frame16.gs,
 272                       frame16.callfrom_ip, frame16.module_cs, frame16.relay,
 273                       frame16.entry_ip, frame16.entry_point,
 274                       frame16.bp, frame16.ip, frame16.cs);
 275
 276                 frame->AddrPC.Mode       = AddrMode1616;
 277                 frame->AddrPC.Segment    = frame16.cs;
 278                 frame->AddrPC.Offset     = frame16.ip;
 279
 280                 frame->AddrFrame.Mode    = AddrMode1616;
 281                 frame->AddrFrame.Segment = SELECTOROF(next_switch);
 282                 frame->AddrFrame.Offset  = frame16.bp;
 283
 284                 frame->AddrStack.Mode    = AddrMode1616;
 285                 frame->AddrStack.Segment = SELECTOROF(next_switch);
 286
 287                 frame->AddrReturn.Mode    = AddrMode1616;
 288                 frame->AddrReturn.Segment = frame16.cs;
 289
 290                 next_switch = curr_switch;
 291                 if (!sw_read_mem(csw, next_switch, &frame32, sizeof(frame32)))
 292                 {
 293                     WARN("Bad stack frame %p\n", (void*)(DWORD_PTR)next_switch);
 294                     goto done_err;
 295                 }
 296                 curr_switch = (DWORD)frame32.frame16;
 297                 tmp.Mode    = AddrMode1616;
 298                 tmp.Segment = SELECTOROF(curr_switch);
 299                 tmp.Offset  = OFFSETOF(curr_switch);
 300
 301                 if (!sw_read_mem(csw, sw_xlat_addr(csw, &tmp), &ch, sizeof(ch)))
 302                     curr_switch = 0;
 303                 curr_mode = stm_16bit;
 304             }
 305         }
 306         else
 307         {
 308             frame->AddrPC = frame->AddrReturn;
 309             if (curr_mode == stm_16bit)
 310             {
 311                 frame->AddrStack.Offset = frame->AddrFrame.Offset + 2 * sizeof(WORD);
 312                 /* "pop up" previous BP value */
 313                 if (!sw_read_mem(csw, sw_xlat_addr(csw, &frame->AddrFrame),
 314                                  &val, sizeof(WORD)))
 315                     goto done_err;
 316                 frame->AddrFrame.Offset = val;
 317             }
 318             else
 319             {
 320                 frame->AddrStack.Offset = frame->AddrFrame.Offset + 2 * sizeof(DWORD);
 321                 /* "pop up" previous EBP value */
 322                 if (!sw_read_mem(csw, frame->AddrFrame.Offset,
 323                                  &frame->AddrFrame.Offset, sizeof(DWORD)))
 324                     goto done_err;
 325             }
 326         }
 327     }
 328
 329     if (curr_mode == stm_16bit)
 330     {
 331         unsigned int     i;
 332
 333         p = sw_xlat_addr(csw, &frame->AddrFrame);
 334         if (!sw_read_mem(csw, p + sizeof(WORD), &val, sizeof(WORD)))
 335             goto done_err;
 336         frame->AddrReturn.Offset = val;
 337         /* get potential cs if a far call was used */
 338         if (!sw_read_mem(csw, p + 2 * sizeof(WORD), &val, sizeof(WORD)))
 339             goto done_err;
 340         if (frame->AddrFrame.Offset & 1)
 341             frame->AddrReturn.Segment = val; /* far call assumed */
 342         else
 343         {
 344             /* not explicitly marked as far call,
 345              * but check whether it could be anyway
 346              */
 347             if ((val & 7) == 7 && val != frame->AddrReturn.Segment)
 348             {
 349                 LDT_ENTRY       le;
 350
 351                 if (GetThreadSelectorEntry(csw->hThread, val, &le) &&
 352                     (le.HighWord.Bits.Type & 0x08)) /* code segment */
 353                 {
 354                     /* it is very uncommon to push a code segment cs as
 355                      * a parameter, so this should work in most cases
 356                      */
 357                     frame->AddrReturn.Segment = val;
 358                 }
 359             }
 360         }
 361         frame->AddrFrame.Offset &= ~1;
 362         /* we "pop" parameters as 16 bit entities... of course, this won't
 363          * work if the parameter is in fact bigger than 16bit, but
 364          * there's no way to know that here
 365          */
 366         for (i = 0; i < sizeof(frame->Params) / sizeof(frame->Params[0]); i++)
 367         {
 368             sw_read_mem(csw, p + (2 + i) * sizeof(WORD), &val, sizeof(val));
 369             frame->Params[i] = val;
 370         }
 371     }
 372     else
 373     {
 374         if (!sw_read_mem(csw, frame->AddrFrame.Offset + sizeof(DWORD),
 375                          &frame->AddrReturn.Offset, sizeof(DWORD)))
 376         {
 377             WARN("Cannot read new frame offset %p\n",
 378                  (void*)(DWORD_PTR)(frame->AddrFrame.Offset + (int)sizeof(DWORD)));
 379             goto done_err;
 380         }
 381         sw_read_mem(csw, frame->AddrFrame.Offset + 2 * sizeof(DWORD),
 382                     frame->Params, sizeof(frame->Params));
 383     }
 384
 385     frame->Far = TRUE;
 386     frame->Virtual = TRUE;
 387     p = sw_xlat_addr(csw, &frame->AddrPC);
 388     if (p && sw_module_base(csw, p))
 389         frame->FuncTableEntry = sw_table_access(csw, p);
 390     else
 391         frame->FuncTableEntry = NULL;
 392
 393     TRACE("Leave: PC=%s Frame=%s Return=%s Stack=%s Mode=%s cSwitch=%p nSwitch=%p FuncTable=%p\n",
 394           wine_dbgstr_addr(&frame->AddrPC),
 395           wine_dbgstr_addr(&frame->AddrFrame),
 396           wine_dbgstr_addr(&frame->AddrReturn),
 397           wine_dbgstr_addr(&frame->AddrStack),
 398           curr_mode == stm_start ? "start" : (curr_mode == stm_16bit ? "16bit" : "32bit"),
 399           (void*)(DWORD_PTR)curr_switch, (void*)(DWORD_PTR)next_switch, frame->FuncTableEntry);
 400
 401     return TRUE;
 402 done_err:
 403     curr_mode = stm_done;
 404     return FALSE;
 405 }
 406
 407 struct cpu cpu_i386 = {
 408     IMAGE_FILE_MACHINE_I386,
 409     4,
 410     i386_get_addr,
 411     i386_stack_walk,
 412 };