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