1 files changed, 122 insertions, 0 deletions
diff --git a/util/signal_handlers.cpp b/util/signal_handlers.cpp
new file mode 100644
index 0000000..0e9ec7a
--- /dev/null
+++ b/util/signal_handlers.cpp
@@ -0,0 +1,122 @@
+// signal_handlers.cpp
+
+/**
+*    Copyright (C) 2010 10gen Inc.
+*
+*    This program is free software: you can redistribute it and/or  modify
+*    it under the terms of the GNU Affero General Public License, version 3,
+*    as published by the Free Software Foundation.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU Affero General Public License for more details.
+*
+*    You should have received a copy of the GNU Affero General Public License
+*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "pch.h"
+
+#include <cstdarg>
+#include <cstdio>
+#include <cstdlib>
+
+#if !defined(_WIN32)  // TODO: windows support
+#include <unistd.h>
+#endif
+
+#if !defined(_WIN32) && !defined(NOEXECINFO)
+#include <execinfo.h>
+#endif
+
+#include "log.h"
+#include "signal_handlers.h"
+
+namespace mongo {
+
+    /*
+     * WARNING: PLEASE READ BEFORE CHANGING THIS MODULE
+     *
+     * All code in this module should be singal-friendly. Before adding any system
+     * call or other dependency, please make sure the latter still holds.
+     *
+     */
+
+    static int rawWrite( int fd , char* c , int size ) {
+#if !defined(_WIN32)
+
+        int toWrite = size;
+        int writePos = 0;
+        int wrote;
+        while ( toWrite > 0 ) {
+            wrote = write( fd , &c[writePos] , toWrite );
+            if ( wrote < 1 ) break;
+            toWrite -= wrote;
+            writePos += wrote;
+        }
+        return writePos;
+
+#else
+
+        return -1;
+
+#endif
+    }
+
+    static int formattedWrite( int fd , const char* format, ... ) {
+        const int MAX_ENTRY = 256;
+        static char entryBuf[MAX_ENTRY];
+
+        va_list ap;
+        va_start( ap , format );
+        int entrySize = vsnprintf( entryBuf , MAX_ENTRY-1 , format , ap );
+        if ( entrySize < 0 ) {
+            return -1;
+        }
+
+        if ( rawWrite( fd , entryBuf , entrySize ) < 0 ) {
+            return -1;
+        }
+
+        return 0;
+    }
+
+    static void formattedBacktrace( int fd ) {
+
+#if !defined(_WIN32) && !defined(NOEXECINFO)
+
+        int numFrames;
+        const int MAX_DEPTH = 20;
+        void* stackFrames[MAX_DEPTH];
+
+        numFrames = backtrace( stackFrames , 20 );
+        for ( int i = 0; i < numFrames; i++ ) {
+            formattedWrite( fd , "%p " , stackFrames[i] );
+        }
+        formattedWrite( fd , "\n" );
+
+        backtrace_symbols_fd( stackFrames , numFrames , fd );
+
+#else
+
+        formattedWrite( fd, "backtracing not implemented for this platform yet\n" );
+
+#endif
+
+    }
+
+    void printStackAndExit( int signalNum ) {
+        int fd = Logstream::getLogDesc();
+
+        if ( fd >= 0 ) {
+            formattedWrite( fd , "Received signal %d\n" , signalNum );
+            formattedWrite( fd , "Backtrace: " );
+            formattedBacktrace( fd );
+            formattedWrite( fd , "===\n" );
+        }
+
+        ::exit( EXIT_ABRUPT );
+    }
+
+} // namespace mongo