Adding upstream version 14.5.upstream/14.5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 183 insertions, 0 deletions

diff --git a/src/backend/port/win32/crashdump.c b/src/backend/port/win32/crashdump.c
new file mode 100644
index 0000000..45b6696
--- /dev/null
+++ b/src/backend/port/win32/crashdump.c
@@ -0,0 +1,183 @@
+/*-------------------------------------------------------------------------
+ *
+ * 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) 1996-2021, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/backend/port/win32/crashdump.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#define WIN32_LEAN_AND_MEAN
+
+/*
+ * Some versions of the MS SDK contain "typedef enum { ... } ;" which the MS
+ * compiler quite sanely complains about. Well done, Microsoft.
+ * This pragma disables the warning just while we include the header.
+ * The pragma is known to work with all (as at the time of writing) supported
+ * versions of MSVC.
+ */
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4091)
+#endif
+#include <dbghelp.h>
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+/*
+ * 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 crash dump\n");
+			return EXCEPTION_CONTINUE_SEARCH;
+		}
+
+		pDump = (MINIDUMPWRITEDUMP) (pg_funcptr_t) GetProcAddress(hDll, "MiniDumpWriteDump");
+
+		if (pDump == NULL)
+		{
+			write_stderr("could not load required functions in dbghelp.dll, cannot write crash dump\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;
+		}
+
+		systemTicks = GetTickCount();
+		snprintf(dumpPath, _MAX_PATH,
+				 "crashdumps\\postgres-pid%0i-%0i.mdmp",
+				 (int) selfPid, (int) 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 %lu\n",
+						 dumpPath, GetLastError());
+			return EXCEPTION_CONTINUE_SEARCH;
+		}
+
+		if ((*pDump) (selfProcHandle, selfPid, dumpFile, dumpType, &ExInfo,
+					  NULL, NULL))
+			write_stderr("wrote crash dump to file \"%s\"\n", dumpPath);
+		else
+			write_stderr("could not write crash dump to file \"%s\": error code %lu\n",
+						 dumpPath, GetLastError());
+
+		CloseHandle(dumpFile);
+	}
+
+	return EXCEPTION_CONTINUE_SEARCH;
+}
+
+
+void
+pgwin32_install_crashdump_handler(void)
+{
+	SetUnhandledExceptionFilter(crashDumpHandler);
+}