This is the core of the Wine debugger. The reverse assember was stolen from Mach more or less intact. It turns out that there are two variables that are set differently if you are reverse assembling 16 bit code, and on the whole it seems to work. NEWS: The internal debugger has *tons* more capability than it did before. I have enclosed some examples that show usage at the end of this file. New features include: 1) Ability of debugger to read debug information from wine executable *and* from Win32 executables. Local variable and line number information is also read and processed. 2) The internal debugger is capable of 'stepping' to the next line number, just like gdb. Examples of the commands are: step stepi si step 3 si 5 next nexti cont 4 finish All of these should be exactly like how gdb does things. 3) The internal debugger now has a sense of what source file and line number a given PC is at. New commands to support this are just like gdb, and include: list dir show dir there are a variety of formats of arguments for the list command. All permutations supported by gdb should also be supported. 4) The internal debugger knows about datatypes of various objects, for both Win32 *and* the debugging information in the wine executable itself. I have enclosed an example of how this works at the end. 5) There are more ways the 'b' command can be used to set breakpoints. Examples are: b *0x8190000 b 1100 b Usage b I don't think this covers all of the permutations that gdb accepts (this should be cleaned up someday so that all possibilities are acceptable). 6) The 'print' and 'x' commands should behave more or less exactly as they do under gdb. The difference is that the way the data is presented will be slightly different, but the content should be fundamentally the same. 7) The internal debugger now supports conditional breakpoints, and automatic display expressions. An example is at the end of this file. The syntax and usage should be identical to that of gdb. 8) Type casts can be made from within the debugger, but they currently don't work with typedef'ed types. They only work with builtin types and named structures unions, etc. The problem is that internally we don't always record the typedefed names of structures, so we have no guarantee that we would know what each type is. This can be fixed, of course - it just takes more memory. Note that in some cases, typedefed structures could be cast using '(struct typedfname)' instead of '(typedfname)'. Technically this isn't quite correct, but if and when the rest of this stuff gets fixed, this would need to get corrected too. NOTES: If it weren't for the fact that gdb doesn't grok the Win32 debug information, you could just use gdb. The internal debugger should be able to read and use debugging information for both Win32 and also for the Wine executable, making it possible to debug the combination of the two together as if it were one large (very large) entity. LIMITATIONS AND DIFFERENCES FROM GDB: You cannot set a breakpoint by file and line number as you can with gdb. Adding support for this wouldn't be all that tough, I guess, but it would be a nuisance. You can set a breakpoint given a function and line number, however. An example would be 'b main:2993'. It turns out that the way the internal data structures are arranged it is a whole lot easier to do things in this way than it would be to try and get the source:line type of breakpoint working, but it would probably be worth it to try. Getting stack traces through Wine itself can be a bit tricky. This is because by default the thing is built with optimization enabled, and as a result sometimes functions don't get frames, and lots of variables are optimized into registers. You can turn off optimization for a few key source files if it will help you. Memory consumption is getting to be a real problem. I think 32Mb is no longer sufficient to debug wine - 48 or 64 is probably a whole lot better. Unfortunately I cannot shut down X to save memory :-). ************************************************************************* EXAMPLES: Here is an example of how I tracked down a bug in Wine. The program is something that just maps and dumps the contents of a Win32 executable. It was dying for some reason. Start the first time through. bash$ ls -l dumpexe.exe -rw-rw-r-- 1 eric devel 168448 Jan 4 13:51 dumpexe.exe bash$ ./wine -debug './dumpexe.exe -symbol ./dumpexe.exe' Warning: invalid dir 'e:\test' in path, deleting it. Win32 task 'W32SXXXX': Breakpoint 1 at 0x081a3450 Loading symbols from ELF file ./wine... Loading symbols from ELF file /usr/X11R6/lib/libXpm.so.4.6... Loading symbols from ELF file /usr/X11R6/lib/libSM.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libICE.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libXext.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libX11.so.6.0... Loading symbols from ELF file /lib/libm.so.5.0.5... Loading symbols from ELF file /lib/libc.so.5.2.18... Loading symbols from ELF file /lib/ld-linux.so.1... Loading symbols from Win32 file ./dumpexe.exe... Stopped on breakpoint 1 at 0x081a3450 (_mainCRTStartup) In 32 bit mode. *** Invalid address 0x414c5ff8 (KERNEL32_NULL_THUNK_DATA+0x3930ee6c) 0x081a3450 (_mainCRTStartup): movl %fs:0,%eax Wine-dbg>b DumpFile Breakpoint 2 at 0x081a0078 (DumpFile+0x9 [dumpexe.c:2723]) Wine-dbg>c Dump File: ./dumpexe.exe Stopped on breakpoint 2 at 0x081a0078 (DumpFile+0x9 [dumpexe.c:2723]) Enter path to file dumpexe.c: ../de 2723 HANDLE hFile = NULL; 0x081a0078 (DumpFile+0x9 [dumpexe.c:2723]): movl $0x0,0xfffffff4(%ebp) Wine-dbg>list 2723 HANDLE hFile = NULL; 2724 HANDLE hMap = NULL; 2725 PSTR lpMap = NULL; 2726 DWORD dwFileSize = 0; 2727 DWORD dwFileSizeHigh = 0; 2728 2729 PIMAGE_DOS_HEADER lpImageDOS = NULL; 2730 PIMAGE_FILE_HEADER lpImageFile = NULL; 2731 PIMAGE_NT_HEADERS lpImageNT = NULL; 2732 2733 /* Wine-dbg>n 10 2747 dwFileSize = GetFileSize(hFile, &dwFileSizeHigh); 0x081a00ea (DumpFile+0x7b [dumpexe.c:2747]): leal 0xfffffff0(%ebp),%eax Wine-dbg>n 2749 && (GetLastError() != NO_ERROR) ) 0x081a00fb (DumpFile+0x8c [dumpexe.c:2749]): cmpl $-1,0xffffffe8(%ebp) Wine-dbg>x/d dwFileSize x/d dwFileSize 168448 Wine-dbg>n 2758 PAGE_READONLY, 0, 0, (LPSTR) NULL); 0x081a0124 (DumpFile+0xb5 [dumpexe.c:2758]): pushl $0x0 Wine-dbg>list 2750 list 2750 2750 { 2751 Fatal("Cannot get size of file %s", lpFileName); 2752 } 2753 2754 /* 2755 * map the file 2756 */ 2757 hMap = CreateFileMapping(hFile, (LPSECURITY_ATTRIBUTES) NULL, 2758 PAGE_READONLY, 0, 0, (LPSTR) NULL); 2759 if( hMap == NULL ) 2760 { Wine-dbg>n 2759 if( hMap == NULL ) 0x081a013b (DumpFile+0xcc [dumpexe.c:2759]): cmpl $0,0xfffffffc(%ebp) Wine-dbg>x hMap 08e48c30 Wine-dbg>n 2767 lpMap = (LPSTR) MapViewOfFile(hMap, FILE_MAP_READ, 0, 0, 0); 0x081a0156 (DumpFile+0xe7 [dumpexe.c:2767]): pushl $0x0 Wine-dbg>n 2768 if( lpMap == NULL ) 0x081a016b (DumpFile+0xfc [dumpexe.c:2768]): cmpl $0,0xffffffe0(%ebp) Wine-dbg>print lpMap 0x414c5f40 Wine-dbg>x lpMap 40007000 Wine-dbg> x/10x 0x40007000 x/10x 0x40007000 0x40007000 (KERNEL32_NULL_THUNK_DATA+0x37e4fe74): *** Invalid address 0x40007000 (KERNEL32_NULL_THUNK_DATA+0x37e4fe74) Wine-dbg>quit $ ******************************************************************* The first time through, we find that MapViewOfFile isn't mapping the file correctly into the virtual address space. Try running again, and step into MapViewOfFile to figure out what went wrong. ******************************************************************* bash$ ./wine -debug './dumpexe.exe -symbol ./dumpexe.exe' Warning: invalid dir 'e:\test' in path, deleting it. Win32 task 'W32SXXXX': Breakpoint 1 at 0x081a3450 Loading symbols from ELF file ./wine... Loading symbols from ELF file /usr/X11R6/lib/libXpm.so.4.6... Loading symbols from ELF file /usr/X11R6/lib/libSM.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libICE.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libXext.so.6.0... Loading symbols from ELF file /usr/X11R6/lib/libX11.so.6.0... Loading symbols from ELF file /lib/libm.so.5.0.5... Loading symbols from ELF file /lib/libc.so.5.2.18... Loading symbols from ELF file /lib/ld-linux.so.1... Loading symbols from Win32 file ./dumpexe.exe... Stopped on breakpoint 1 at 0x081a3450 (_mainCRTStartup) In 32 bit mode. *** Invalid address 0x414c5ff8 (KERNEL32_NULL_THUNK_DATA+0x3930ee6c) 0x081a3450 (_mainCRTStartup): movl %fs:0,%eax Wine-dbg>b DumpFile:2767 Breakpoint 2 at 0x081a0156 (DumpFile+0xe7 [dumpexe.c:2767]) Wine-dbg>c Dump File: ./dumpexe.exe Stopped on breakpoint 2 at 0x081a0156 (DumpFile+0xe7 [dumpexe.c:2767]) Enter path to file dumpexe.c: ../de 2767 lpMap = (LPSTR) MapViewOfFile(hMap, FILE_MAP_READ, 0, 0, 0); 0x081a0156 (DumpFile+0xe7 [dumpexe.c:2767]): pushl $0x0 Wine-dbg>step 390 0385 stdcall MapViewOfFile(long long long long long) MapViewOfFile 0x080d793c (KERNEL32_385 [kernel32.spec:390]): pushl %ebp Wine-dbg>step 223 if (!debugging_relay) return; 0x080c83dc (RELAY_DebugCallFrom32+0xc [relay.c:223]): cmpw $0,0x644a Wine-dbg> 244 } 0x080c848e (RELAY_DebugCallFrom32+0xbe [relay.c:244]): leal 0xfffffff4(%ebp),%esp Wine-dbg> 103 return MapViewOfFileEx(handle,access,offhi,offlo,size,0); 0x080911a4 (MapViewOfFile+0x14 [file.c:103]): pushl $0x0 Wine-dbg> 113 FILEMAP_OBJECT *fmap = (FILEMAP_OBJECT*)handle; 0x080911cf (MapViewOfFileEx+0xf [file.c:113]): movl 0x8(%ebp),%esi Wine-dbg>n 115 if (!size) size = fmap->size; 0x080911d2 (MapViewOfFileEx+0x12 [file.c:115]): testl %ebx,%ebx Wine-dbg>list list 115 if (!size) size = fmap->size; 116 if (!size) size = 1; 117 return mmap ((caddr_t)st, size, fmap->prot, 118 MAP_ANON|MAP_PRIVATE, 119 FILE_GetUnixHandle(fmap->hfile), 120 offlo); 121 } 122 123 /*********************************************************************** 124 * UnmapViewOfFile (KERNEL32.385) 125 */ Wine-dbg>x size 00000000 Wine-dbg>n 116 if (!size) size = 1; 0x080911d9 (MapViewOfFileEx+0x19 [file.c:116]): testl %ebx,%ebx Wine-dbg>x size 00000000 Wine-dbg>n 117 return mmap ((caddr_t)st, size, fmap->prot, 0x080911e2 (MapViewOfFileEx+0x22 [file.c:117]): pushl %eax Wine-dbg>x size 00000000 Wine-dbg>info local MapViewOfFileEx:handle == 0x08e48c90 MapViewOfFileEx:access == 0x00000004 MapViewOfFileEx:offhi == 0x00000000 MapViewOfFileEx:offlo == 0x00000000 MapViewOfFileEx:size == 0x00000000 MapViewOfFileEx:st == 0x00000000 MapViewOfFileEx:offlo optimized into register $eax MapViewOfFileEx:size optimized into register $ebx MapViewOfFileEx:st optimized into register $edi MapViewOfFileEx:fmap optimized into register $esi Wine-dbg>print $ebx 0x0001 Wine-dbg>bt bt Backtrace: =>0 0x080911e2 (MapViewOfFileEx+0x22 [file.c:117]) 1 0x080911b0 (MapViewOfFile+0x20(handle=0x8e48c90, access=0x4, offhi=0x0, offlo=0x0, size=0x0) [file.c:104]) 2 0x08104ab5 (CallFrom32_stdcall_5+0x25 [callfrom32.s]) 3 0x081a0168 (DumpFile+0xf9(lpFileName=0x414c61ed) [dumpexe.c:2767]) 4 0x081a0c35 (main+0x410(argc=0x3, argv=0x414c61cc) [dumpexe.c:3078]) 5 0x081a3514 (_mainCRTStartup+0xc4) 6 0x0810549f (Code_Start+0x13 [callto32.s]) 7 0x0802fdac (TASK_CallToStart+0x8c [task.c:373]) Wine-dbg> ******************************************************************* Notice that you can step through the thunks into our own transfer routines. You will notice that the source line displays as something like: 390 0385 stdcall MapViewOfFile(long long long long long) MapViewOfFile This is just the source line from the spec file that caused the transfer routine to be generated. From this you can step again, and you step into the relay logging code - keep stepping and you eventually step into the actual function that does the dirty work. At this point an examination of the source to the Win32 program and an examination of the source to win32/file.s showed where the problem was. When you specify 0 for the size of the object in CreateFileMapping, it is supposed to use the entire size of the file as the size of the object. Instead we were just blindly copying the number over. ******************************************************************* Wine-dbg>b main Breakpoint 1 at 0x080108c0 (main [dbgmain.c:213]) Wine-dbg>print breakpoints[1] {addr={type=0x08043000, seg=0, off=134285504}, addrlen=' ', opcode='U', enabled=1, skipcount=0, in_use=1} Wine-dbg> print breakpoints[1].enabled 1 Wine-dbg>set breakpoints[0].enabled = 0 Wine-dbg>print breakpoints[0].enabled 0 Wine-dbg>print type_hash_table[1]->type STRUCT Wine-dbg>print type_hash_table[1] 0x08072020 Wine-dbg>print *type_hash_table[1] print *type_hash_table[1] {type=STRUCT, next=0x00000000, name="LOGPALETTE", un={basic={basic_type=8, output_format="�V�M", basic_size=-128, b_signed=0}, bitfield={bitoff=8, nbits=0, basetype=0x081d56c0}, pointer={pointsto=0x00000008}, funct={rettype=0x00000008}, array={start=8, end=136140480, basictype=0x08043e80}, structure={size=8, members=0x081d56c0}, enumeration={members=0x00000008}}} Wine-dbg> ******************************************************************* This example shows how you can print out various data structures. Note that enumerated types are displayed in the symbolic form, and strings are displayed in the expected manner. You can use the set command to set more or less anything. Note however that you cannot use enumerated types on the RHS of the expression. ******************************************************************* Wine-dbg>list 2986 if( argc <= 1 ) 2987 { 2988 Usage(argv[0]); 2989 } 2990 2991 for( i = 1; i < argc; i++ ) 2992 { 2993 if( strncmp(argv[i], "-dos", sizeof("-dos") - 1) == 0 ) 2994 { 2995 DmpCtrl.bDumpDOSHeader = TRUE; 2996 } Wine-dbg>b 2993 Breakpoint 3 at 0x081a8861 (main+0x3c [dumpexe.c:2993]) Wine-dbg>condition 3 i == 2 Wine-dbg>c Stopped on breakpoint 3 at 0x081a8861 (main+0x3c [dumpexe.c:2993]) 2993 if( strncmp(argv[i], "-dos", sizeof("-dos") - 1) == 0 ) 0x081a8861 (main+0x3c [dumpexe.c:2993]): pushl $0x4 Wine-dbg>print i 2 Wine-dbg>print argv[i] "./dumpexe.exe" ******************************************************************* This example shows how to use conditional breakpoints. Here is another one that demonstrates another cool feature conditional breakpoints that involve a function call: condition 3 strcmp(argv[i], "./dumpexe.exe") == 0 ******************************************************************* Wine-dbg>list 2986 if( argc <= 1 ) 2987 { 2988 Usage(argv[0]); 2989 } 2990 2991 for( i = 1; i < argc; i++ ) 2992 { 2993 if( strncmp(argv[i], "-dos", sizeof("-dos") - 1) == 0 ) 2994 { 2995 DmpCtrl.bDumpDOSHeader = TRUE; 2996 } Wine-dbg>b 2993 Breakpoint 3 at 0x081a8861 (main+0x3c [dumpexe.c:2993]) Wine-dbg>condition 3 strcmp(argv[i], "./dumpexe.exe") == 0 Wine-dbg>info break Breakpoints: 1: y 0x081ab450 (_mainCRTStartup) 2: y 0x081a882e (main+0x9 [dumpexe.c:2986]) 3: y 0x081a8861 (main+0x3c [dumpexe.c:2993]) stop when ( strcmp(( argv[i] ), "./dumpexe.exe") == 0 ) Wine-dbg>c Stopped on breakpoint 3 at 0x081a8861 (main+0x3c [dumpexe.c:2993]) 2993 if( strncmp(argv[i], "-dos", sizeof("-dos") - 1) == 0 ) 0x081a8861 (main+0x3c [dumpexe.c:2993]): pushl $0x4 Wine-dbg>print i 2 Wine-dbg>print argv[i] "./dumpexe.exe" Wine-dbg>