1 /**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28 /**
29 * @file
30 * Symbol lookup.
31 *
32 * @author Jose Fonseca <jfonseca@vmware.com>
33 */
34
35 #include "pipe/p_compiler.h"
36 #include "os/os_thread.h"
37 #include "u_string.h"
38
39 #include "u_debug.h"
40 #include "u_debug_symbol.h"
41 #include "u_hash_table.h"
42
43
44 #if defined(PIPE_OS_WINDOWS)
45
46 #include <windows.h>
47 #include <stddef.h>
48
49 #include "dbghelp.h"
50
51
52 /**
53 * SymInitialize() must be called once for each process (in this case, the
54 * current process), before any of the other functions can be called.
55 */
56 static BOOL g_bSymInitialized = FALSE;
57
58
59 /**
60 * Lookup the address of a DbgHelp function.
61 */
62 static FARPROC WINAPI
getDbgHelpProcAddress(LPCSTR lpProcName)63 getDbgHelpProcAddress(LPCSTR lpProcName)
64 {
65 static HMODULE hModule = NULL;
66
67 if (!hModule) {
68 static boolean bail = FALSE;
69
70 if (bail) {
71 return NULL;
72 }
73
74 #ifdef PIPE_CC_GCC
75 /*
76 * DbgHelp does not understand the debug information generated by MinGW toolchain.
77 *
78 * mgwhelp.dll is a dbghelp.dll look-alike replacement, which is able to
79 * understand MinGW symbols, including on 64-bit builds.
80 */
81 if (!hModule) {
82 hModule = LoadLibraryA("mgwhelp.dll");
83 if (!hModule) {
84 _debug_printf("warning: mgwhelp.dll not found: symbol names will not be resolved\n"
85 "warning: download it from https://github.com/jrfonseca/drmingw/#mgwhelp\n");
86 }
87 }
88 #endif
89
90 /*
91 * Fallback to the real DbgHelp.
92 */
93 if (!hModule) {
94 hModule = LoadLibraryA("dbghelp.dll");
95 }
96
97 if (!hModule) {
98 bail = TRUE;
99 return NULL;
100 }
101 }
102
103 return GetProcAddress(hModule, lpProcName);
104 }
105
106
107 /**
108 * Generic macro to dispatch a DbgHelp functions.
109 */
110 #define DBGHELP_DISPATCH(_name, _ret_type, _ret_default, _arg_types, _arg_names) \
111 static _ret_type WINAPI \
112 j_##_name _arg_types \
113 { \
114 typedef BOOL (WINAPI *PFN) _arg_types; \
115 static PFN pfn = NULL; \
116 if (!pfn) { \
117 pfn = (PFN) getDbgHelpProcAddress(#_name); \
118 if (!pfn) { \
119 return _ret_default; \
120 } \
121 } \
122 return pfn _arg_names; \
123 }
124
125 DBGHELP_DISPATCH(SymInitialize,
126 BOOL, 0,
127 (HANDLE hProcess, PSTR UserSearchPath, BOOL fInvadeProcess),
128 (hProcess, UserSearchPath, fInvadeProcess))
129
130 DBGHELP_DISPATCH(SymSetOptions,
131 DWORD, FALSE,
132 (DWORD SymOptions),
133 (SymOptions))
134
135 DBGHELP_DISPATCH(SymFromAddr,
136 BOOL, FALSE,
137 (HANDLE hProcess, DWORD64 Address, PDWORD64 Displacement, PSYMBOL_INFO Symbol),
138 (hProcess, Address, Displacement, Symbol))
139
140 DBGHELP_DISPATCH(SymGetLineFromAddr64,
141 BOOL, FALSE,
142 (HANDLE hProcess, DWORD64 dwAddr, PDWORD pdwDisplacement, PIMAGEHLP_LINE64 Line),
143 (hProcess, dwAddr, pdwDisplacement, Line))
144
145
146 #undef DBGHELP_DISPATCH
147
148
149 static inline boolean
debug_symbol_name_dbghelp(const void * addr,char * buf,unsigned size)150 debug_symbol_name_dbghelp(const void *addr, char* buf, unsigned size)
151 {
152 DWORD64 dwAddr = (DWORD64)(uintptr_t)addr;
153 HANDLE hProcess = GetCurrentProcess();
154
155 /* General purpose buffer, to back pSymbol and other temporary stuff.
156 * Must not be too memory hungry here to avoid stack overflows.
157 */
158 CHAR buffer[512];
159
160 PSYMBOL_INFO pSymbol = (PSYMBOL_INFO) buffer;
161 DWORD64 dwDisplacement = 0; /* Displacement of the input address, relative to the start of the symbol */
162 DWORD dwLineDisplacement = 0;
163 IMAGEHLP_LINE64 Line;
164
165 memset(pSymbol, 0, sizeof *pSymbol);
166 pSymbol->SizeOfStruct = sizeof buffer;
167 pSymbol->MaxNameLen = sizeof buffer - offsetof(SYMBOL_INFO, Name);
168
169 if (!g_bSymInitialized) {
170 j_SymSetOptions(/* SYMOPT_UNDNAME | */ SYMOPT_LOAD_LINES);
171 if (j_SymInitialize(hProcess, NULL, TRUE)) {
172 g_bSymInitialized = TRUE;
173 }
174 }
175
176 /* Lookup symbol name */
177 if (!g_bSymInitialized ||
178 !j_SymFromAddr(hProcess, dwAddr, &dwDisplacement, pSymbol)) {
179 /*
180 * We couldn't obtain symbol information. At least tell which module the address belongs.
181 */
182
183 HMODULE hModule = NULL;
184
185 if (!GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
186 (LPCTSTR)addr,
187 &hModule)) {
188 return FALSE;
189 }
190
191 if (GetModuleFileNameA(hModule, buffer, sizeof buffer) == sizeof buffer) {
192 return FALSE;
193 }
194 util_snprintf(buf, size, "%p at %s+0x%lx",
195 addr, buffer,
196 (unsigned long)((uintptr_t)addr - (uintptr_t)hModule));
197
198 return TRUE;
199 }
200
201 /*
202 * Try to get filename and line number.
203 */
204 memset(&Line, 0, sizeof Line);
205 Line.SizeOfStruct = sizeof Line;
206 if (!j_SymGetLineFromAddr64(hProcess, dwAddr, &dwLineDisplacement, &Line)) {
207 Line.FileName = NULL;
208 }
209
210 if (Line.FileName) {
211 util_snprintf(buf, size, "%s at %s:%lu", pSymbol->Name, Line.FileName, Line.LineNumber);
212 } else {
213 util_snprintf(buf, size, "%s", pSymbol->Name);
214 }
215
216 return TRUE;
217 }
218
219 #endif /* PIPE_OS_WINDOWS */
220
221
222 #if defined(__GLIBC__) && !defined(__UCLIBC__)
223
224 #include <execinfo.h>
225
226 /* This can only provide dynamic symbols, or binary offsets into a file.
227 *
228 * To fix this, post-process the output with tools/addr2line.sh
229 */
230 static inline boolean
debug_symbol_name_glibc(const void * addr,char * buf,unsigned size)231 debug_symbol_name_glibc(const void *addr, char* buf, unsigned size)
232 {
233 char** syms = backtrace_symbols((void**)&addr, 1);
234 if (!syms) {
235 return FALSE;
236 }
237 strncpy(buf, syms[0], size);
238 buf[size - 1] = 0;
239 free(syms);
240 return TRUE;
241 }
242
243 #endif /* defined(__GLIBC__) && !defined(__UCLIBC__) */
244
245
246 void
debug_symbol_name(const void * addr,char * buf,unsigned size)247 debug_symbol_name(const void *addr, char* buf, unsigned size)
248 {
249 #if defined(PIPE_OS_WINDOWS)
250 if (debug_symbol_name_dbghelp(addr, buf, size)) {
251 return;
252 }
253 #endif
254
255 #if defined(__GLIBC__) && !defined(__UCLIBC__)
256 if (debug_symbol_name_glibc(addr, buf, size)) {
257 return;
258 }
259 #endif
260
261 util_snprintf(buf, size, "%p", addr);
262 buf[size - 1] = 0;
263 }
264
265 void
debug_symbol_print(const void * addr)266 debug_symbol_print(const void *addr)
267 {
268 char buf[1024];
269 debug_symbol_name(addr, buf, sizeof(buf));
270 debug_printf("\t%s\n", buf);
271 }
272
273 struct util_hash_table* symbols_hash;
274 pipe_static_mutex(symbols_mutex);
275
hash_ptr(void * p)276 static unsigned hash_ptr(void* p)
277 {
278 return (unsigned)(uintptr_t)p;
279 }
280
compare_ptr(void * a,void * b)281 static int compare_ptr(void* a, void* b)
282 {
283 if(a == b)
284 return 0;
285 else if(a < b)
286 return -1;
287 else
288 return 1;
289 }
290
291 const char*
debug_symbol_name_cached(const void * addr)292 debug_symbol_name_cached(const void *addr)
293 {
294 const char* name;
295 #ifdef PIPE_SUBSYSTEM_WINDOWS_USER
296 static boolean first = TRUE;
297
298 if (first) {
299 pipe_mutex_init(symbols_mutex);
300 first = FALSE;
301 }
302 #endif
303
304 pipe_mutex_lock(symbols_mutex);
305 if(!symbols_hash)
306 symbols_hash = util_hash_table_create(hash_ptr, compare_ptr);
307 name = util_hash_table_get(symbols_hash, (void*)addr);
308 if(!name)
309 {
310 char buf[1024];
311 debug_symbol_name(addr, buf, sizeof(buf));
312 name = strdup(buf);
313
314 util_hash_table_set(symbols_hash, (void*)addr, (void*)name);
315 }
316 pipe_mutex_unlock(symbols_mutex);
317 return name;
318 }
319