--- /dev/null
+/*-------------------------------------------------------------------------
+ *
+ * win32_crashdump.c
+ * Automatic crash dump creation for PostgreSQL on Windows
+ *
+ * The crashdump feature traps unhandled win32 exceptions produced by the
+ * backend, and tries to produce a Windows MiniDump crash
+ * dump for later debugging and analysis. The machine performing the dump
+ * doesn't need any special debugging tools; the user only needs to send
+ * the dump to somebody who has the same version of PostgreSQL and has debugging
+ * tools.
+ *
+ * crashdump module originally by Craig Ringer <ringerc@ringerc.id.au>
+ *
+ * LIMITATIONS
+ * ===========
+ * This *won't* work in hard OOM situations or stack overflows.
+ *
+ * For those, it'd be necessary to take a much more complicated approach where
+ * the handler switches to a new stack (if it can) and forks a helper process
+ * to debug it self.
+ *
+ * POSSIBLE FUTURE WORK
+ * ====================
+ * For bonus points, the crash dump format permits embedding of user-supplied
+ * data. If there's anything else that should always be supplied with a crash
+ * dump (postgresql.conf? Last few lines of a log file?), it could potentially
+ * be added, though at the cost of a greater chance of the crash dump failing.
+ *
+ *
+ * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/port/win32/crashdump.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <string.h>
+#include <dbghelp.h>
+
+/*
+ * Much of the following code is based on CodeProject and MSDN examples,
+ * particularly
+ * http://www.codeproject.com/KB/debug/postmortemdebug_standalone1.aspx
+ *
+ * Useful MSDN articles:
+ *
+ * http://msdn.microsoft.com/en-us/library/ff805116(v=VS.85).aspx
+ * http://msdn.microsoft.com/en-us/library/ms679294(VS.85).aspx
+ *
+ * Other useful articles on working with minidumps:
+ * http://www.debuginfo.com/articles/effminidumps.html
+ */
+
+typedef BOOL (WINAPI *MINIDUMPWRITEDUMP)(HANDLE hProcess, DWORD dwPid, HANDLE hFile, MINIDUMP_TYPE DumpType,
+ CONST PMINIDUMP_EXCEPTION_INFORMATION ExceptionParam,
+ CONST PMINIDUMP_USER_STREAM_INFORMATION UserStreamParam,
+ CONST PMINIDUMP_CALLBACK_INFORMATION CallbackParam
+ );
+
+
+/*
+ * This function is the exception handler passed to SetUnhandledExceptionFilter.
+ * It's invoked only if there's an unhandled exception. The handler will use
+ * dbghelp.dll to generate a crash dump, then resume the normal unhandled
+ * exception process, which will generally exit with an error message from
+ * the runtime.
+ *
+ * This function is run under the unhandled exception handler, effectively
+ * in a crash context, so it should be careful with memory and avoid using
+ * any PostgreSQL functions.
+ */
+static LONG WINAPI
+crashDumpHandler(struct _EXCEPTION_POINTERS *pExceptionInfo)
+{
+ /*
+ * We only write crash dumps if the "crashdumps" directory within
+ * the postgres data directory exists.
+ */
+ DWORD attribs = GetFileAttributesA("crashdumps");
+ if (attribs != INVALID_FILE_ATTRIBUTES && (attribs & FILE_ATTRIBUTE_DIRECTORY) )
+ {
+ /* 'crashdumps' exists and is a directory. Try to write a dump' */
+ HMODULE hDll = NULL;
+ MINIDUMPWRITEDUMP pDump = NULL;
+ MINIDUMP_TYPE dumpType;
+ char dumpPath[_MAX_PATH];
+ HANDLE selfProcHandle = GetCurrentProcess();
+ DWORD selfPid = GetProcessId(selfProcHandle);
+ HANDLE dumpFile;
+ DWORD systemTicks;
+ struct _MINIDUMP_EXCEPTION_INFORMATION ExInfo;
+
+ ExInfo.ThreadId = GetCurrentThreadId();
+ ExInfo.ExceptionPointers = pExceptionInfo;
+ ExInfo.ClientPointers = FALSE;
+
+ /* Load the dbghelp.dll library and functions */
+ hDll = LoadLibrary("dbghelp.dll");
+ if (hDll == NULL)
+ {
+ write_stderr("could not load dbghelp.dll, cannot write crashdump\n");
+ return EXCEPTION_CONTINUE_SEARCH;
+ }
+
+ pDump = (MINIDUMPWRITEDUMP)GetProcAddress(hDll, "MiniDumpWriteDump");
+
+ if (pDump==NULL)
+ {
+ write_stderr("could not load required functions in dbghelp.dll, cannot write crashdump\n");
+ return EXCEPTION_CONTINUE_SEARCH;
+ }
+
+ /*
+ * Dump as much as we can, except shared memory, code segments,
+ * and memory mapped files.
+ * Exactly what we can dump depends on the version of dbghelp.dll,
+ * see:
+ * http://msdn.microsoft.com/en-us/library/ms680519(v=VS.85).aspx
+ */
+ dumpType = MiniDumpNormal | MiniDumpWithHandleData |
+ MiniDumpWithDataSegs;
+
+ if (GetProcAddress(hDll, "EnumDirTree") != NULL)
+ {
+ /* If this function exists, we have version 5.2 or newer */
+ dumpType |= MiniDumpWithIndirectlyReferencedMemory |
+ MiniDumpWithPrivateReadWriteMemory;
+ }
+ if (GetProcAddress(hDll, "SymFromIndex") != NULL)
+ {
+ /* If this function exists, we have version 6.2 or newer */
+ dumpType |= MiniDumpWithThreadInfo;
+ }
+
+ systemTicks = GetTickCount();
+ snprintf(dumpPath, _MAX_PATH,
+ "crashdumps\\postgres-pid%0i-%0i.mdmp", selfPid, systemTicks);
+ dumpPath[_MAX_PATH-1] = '\0';
+
+ dumpFile = CreateFile(dumpPath, GENERIC_WRITE, FILE_SHARE_WRITE,
+ NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL,
+ NULL);
+ if (dumpFile==INVALID_HANDLE_VALUE)
+ {
+ write_stderr("could not open crash dump file %s for writing: error code %d\n",
+ dumpPath, GetLastError());
+ return EXCEPTION_CONTINUE_SEARCH;
+ }
+
+ if ((*pDump)(selfProcHandle, selfPid, dumpFile, dumpType, &ExInfo,
+ NULL, NULL))
+ write_stderr("wrote crash dump to %s\n", dumpPath);
+ else
+ write_stderr("could not write crash dump to %s: error code %08x\n",
+ dumpPath, GetLastError());
+
+ CloseHandle(dumpFile);
+ }
+
+ return EXCEPTION_CONTINUE_SEARCH;
+}
+
+
+void
+pgwin32_install_crashdump_handler(void)
+{
+ SetUnhandledExceptionFilter(crashDumpHandler);
+}
projects / postgresql / commitdiff