1 /*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "windows.h"
9 #include "win_dbghelp.h"
10
11 #include <process.h>
12 #include <string.h>
13 #include <stdlib.h>
14 #include <stdio.h>
15
16 // Remove prefix addresses. 18 = 2 * (8 digit hexa + 1 space).
17 // e.g. "abcd1234 abcd1234 render_pdf!processInput
18 #define CDB_CALLSTACK_PREFIX (18)
19
20 // CDB.EXE prints a lot of garbage and there is no argument to pass which
21 // would remove all that noise.
22 // Using eval feature that evaluates a number in hex and prints it to stdout
23 // to mark where the callstack is printed.
24 // For example, each thread's callstack will be marked with "12340000" at
25 // the beginning and "12340001" at the end.
26 // We just made up these numbers; they could be anything, as long as they
27 // match up with their decimal equivalents.
28
29 #define MARKER_THREAD_CALLSTACK_START_NUMBER "12340000"
30 #define MARKER_THREAD_CALLSTACK_START "Evaluate expression: 305397760 = 12340000"
31
32 #define MARKER_THREAD_CALLSTACK_STOP_NUMBER "12340001"
33 #define MARKER_THREAD_CALLSTACK_STOP "Evaluate expression: 305397761 = 12340001"
34
35 #define MARKER_EXCEPTION_CALLSTACK_START_NUMBER "12340002"
36 #define MARKER_EXCEPTION_CALLSTACK_START "Evaluate expression: 305397762 = 12340002"
37
38 #define MARKER_EXCEPTION_CALLSTACK_STOP_NUMBER "12340003"
39 #define MARKER_EXCEPTION_CALLSTACK_STOP "Evaluate expression: 305397763 = 12340003"
40
41 // k - print stack
42 // ? val - evaluate expression. Used to mark the log file.
43 // .ecxr - load exception, if exception was thrown.
44 // k - print the resolved stack by .ecxr
45 // q - quit cdb.exe
46 #define CDB_PRINT_CALLSTACK_CURRENT_THREAD "? " MARKER_THREAD_CALLSTACK_START_NUMBER "; k; ? " MARKER_THREAD_CALLSTACK_STOP_NUMBER "; .ecxr; ? " MARKER_EXCEPTION_CALLSTACK_START_NUMBER "; k; ? " MARKER_EXCEPTION_CALLSTACK_STOP_NUMBER "; q"
47
strncpyOrSetBlank(char * dest,const char * src,size_t len)48 static void strncpyOrSetBlank(char* dest, const char* src, size_t len) {
49 const char* srcOrEmptyString = (nullptr == src) ? "" : src;
50 strncpy(dest, srcOrEmptyString, len);
51 }
52
53 char debug_app_name[MAX_PATH] = "";
setAppName(const char * app_name)54 void setAppName(const char* app_name) {
55 strncpyOrSetBlank(debug_app_name, app_name, sizeof(debug_app_name));
56 }
57
getAppName()58 const char* getAppName() {
59 return debug_app_name;
60 }
61
62 char debug_binaries_path[MAX_PATH] = "";
setBinariesPath(const char * binaries_path)63 void setBinariesPath(const char* binaries_path) {
64 strncpyOrSetBlank(debug_binaries_path, binaries_path,
65 sizeof(debug_binaries_path));
66 }
67
getBinariesPath()68 const char* getBinariesPath() {
69 return debug_binaries_path;
70 }
71
72 char debug_app_version[100] = "";
setAppVersion(const char * version)73 void setAppVersion(const char* version) {
74 strncpyOrSetBlank(debug_app_version, version, sizeof(debug_app_version));
75 }
76
getAppVersion()77 const char* getAppVersion() {
78 return debug_app_version;
79 }
80
81 char debug_cdb_path[MAX_PATH] = "";
setCdbPath(const char * path)82 void setCdbPath(const char* path) {
83 strncpyOrSetBlank(debug_cdb_path, path, sizeof(debug_cdb_path));
84 }
85
getCdbPath()86 const char* getCdbPath() {
87 return debug_cdb_path;
88 }
89
90 /** Print all the lines of a CDB k command whicha are callstacks.
91 * Callstack lines are marked by start and stop markers and they are prefixed
92 * byt 2 hex adresses, which will not be reported.
93 */
printCallstack(const char * filename,const char * start,const char * stop)94 static void printCallstack(const char* filename,
95 const char* start,
96 const char* stop) {
97 FILE* file = fopen(filename, "rt");
98 char line[1000];
99 bool started = false;
100 // Not the most performant code, but this will be used only to collect
101 // the callstack from a log files, only when the application had failed.
102 while (fgets(line, sizeof(line), file)) {
103 if (!started && strncmp(start, line, strlen(start)) == 0) {
104 started = true;
105 } else if (started && strncmp(stop, line, strlen(stop)) == 0) {
106 break;
107 } else if (started) {
108 // Filter messages. Calstack lines contain "exe/dll!function"
109 if (strchr(line, '!') != nullptr && strlen(line) > CDB_CALLSTACK_PREFIX) {
110 printf("%s", line + CDB_CALLSTACK_PREFIX); // fgets includes \n already.
111 }
112 }
113 }
114 fclose(file);
115 }
116
117 #define BUILD_UNIQUE_FILENAME(var, ext, szPath, szAppName, szVersion, stLocalTime) \
118 sprintf(szFileName, "%s%s\\%s-%04d%02d%02d-%02d%02d%02d-%ld-%ld" ext, \
119 szPath, szAppName, szVersion, \
120 stLocalTime.wYear, stLocalTime.wMonth, stLocalTime.wDay, \
121 stLocalTime.wHour, stLocalTime.wMinute, stLocalTime.wSecond, \
122 GetCurrentProcessId(), GetCurrentThreadId());
123
124 // Exception execution handler. Exception is recognized. Transfer control to
125 // the exception handler by executing the __except compound statement,
126 // then continue execution after the __except block.
GenerateDumpAndPrintCallstack(EXCEPTION_POINTERS * pExceptionPointers)127 int GenerateDumpAndPrintCallstack(EXCEPTION_POINTERS* pExceptionPointers) {
128 BOOL bMiniDumpSuccessful;
129 char szPath[MAX_PATH];
130 char szFileName[MAX_PATH];
131 char szFileNameOutput[MAX_PATH];
132 const char* szAppName = getAppName();
133 const char* szVersion = getAppVersion();
134 DWORD dwBufferSize = MAX_PATH;
135 HANDLE hDumpFile;
136 SYSTEMTIME stLocalTime;
137 MINIDUMP_EXCEPTION_INFORMATION ExpParam;
138
139 GetLocalTime( &stLocalTime );
140 GetTempPath( dwBufferSize, szPath );
141
142 sprintf( szFileName, "%s%s", szPath, szAppName );
143 CreateDirectory( szFileName, nullptr );
144
145 BUILD_UNIQUE_FILENAME(szFileName, ".dmp", szPath, szAppName, szVersion, stLocalTime);
146 BUILD_UNIQUE_FILENAME(szFileNameOutput, ".out", szPath, szAppName, szVersion, stLocalTime);
147
148 hDumpFile = CreateFile(szFileName,
149 GENERIC_READ|GENERIC_WRITE,
150 FILE_SHARE_WRITE|FILE_SHARE_READ,
151 0,
152 CREATE_ALWAYS,
153 0,
154 0);
155
156 ExpParam.ThreadId = GetCurrentThreadId();
157 ExpParam.ExceptionPointers = pExceptionPointers;
158 ExpParam.ClientPointers = TRUE;
159
160 bMiniDumpSuccessful = MiniDumpWriteDump(GetCurrentProcess(),
161 GetCurrentProcessId(),
162 hDumpFile,
163 MiniDumpWithDataSegs,
164 &ExpParam,
165 nullptr,
166 nullptr);
167
168 printf("MiniDump file: %s\n", szFileName);
169 printf("App exe and pdb: %s\n", getBinariesPath());
170
171 const char* cdbExePath = getCdbPath();
172 if (cdbExePath && *cdbExePath != '\0') {
173 printf("Cdb exe: %s\n", cdbExePath);
174
175 char command[MAX_PATH * 4];
176 sprintf(command, "%s -y \"%s\" -i \"%s\" -z \"%s\" -c \"%s\" -kqm >\"%s\"",
177 cdbExePath,
178 getBinariesPath(),
179 getBinariesPath(),
180 szFileName,
181 CDB_PRINT_CALLSTACK_CURRENT_THREAD,
182 szFileNameOutput);
183 system(command);
184
185 printf("\nThread Callstack:\n");
186 printCallstack(szFileNameOutput,
187 MARKER_THREAD_CALLSTACK_START,
188 MARKER_THREAD_CALLSTACK_STOP);
189
190 printf("\nException Callstack:\n");
191 printCallstack(szFileNameOutput,
192 MARKER_EXCEPTION_CALLSTACK_START,
193 MARKER_EXCEPTION_CALLSTACK_STOP);
194 } else {
195 printf("Warning: CDB path not set up.\n");
196 }
197
198 return EXCEPTION_EXECUTE_HANDLER;
199 }
200
201 /** Sets the debugging variables. Input parameter is app location.
202 * e.g out\Debug\render_pdfs.exe
203 * This function expects the .pdb file to be in the same directory.
204 */
setUpDebuggingFromArgs(const char * vargs0)205 void setUpDebuggingFromArgs(const char* vargs0) {
206 size_t i = strlen(vargs0);
207
208 if (i >= 4 && _stricmp(vargs0 - 4, ".exe") == 0) {
209 // Ignore .exe
210 i -= 4;
211 }
212
213 size_t pos_period = i;
214
215 // Find last \ in path - this is Windows!
216 while (i >= 0 && vargs0[i] != '\\') {
217 i--;
218 }
219
220 size_t pos_last_slash = i;
221
222 char app_name[MAX_PATH];
223 strncpy(app_name, vargs0 + pos_last_slash + 1, pos_period - pos_last_slash - 1);
224 app_name[pos_period - pos_last_slash] = '\0';
225 setAppName(app_name);
226
227 char binaries_path[MAX_PATH];
228 strncpy(binaries_path, vargs0, pos_last_slash);
229 binaries_path[pos_last_slash] = '\0';
230 setBinariesPath(binaries_path);
231
232 setAppVersion("1.0"); // Dummy for now, but use revision instead if we use
233 // the minidump for anything else other than
234 // collecting the callstack.
235
236 // cdb.exe is the app used to load the minidump which prints the callstack.
237 char cdbExePath[MAX_PATH];
238 #ifdef _WIN64
239 sprintf(cdbExePath, "%s\\x64\\cdb.exe", SK_CDB_PATH);
240 #else
241 sprintf(cdbExePath, "%s\\cdb.exe", SK_CDB_PATH);
242 #endif
243 setCdbPath(cdbExePath);
244 }
245