Merge branch 'dev-signals'

include/internal/catch_fatal_condition.hpp

@@ -12,25 +12,76 @@
 
 namespace Catch {
 
-    // Report the error condition then exit the process
-    inline void fatal( std::string const& message, int exitCode ) {
+    // Report the error condition
+    inline void reportFatal( std::string const& message, int exitCode ) {
         IContext& context = Catch::getCurrentContext();
         IResultCapture* resultCapture = context.getResultCapture();
         resultCapture->handleFatalErrorCondition( message );
-
-		if( Catch::alwaysTrue() ) // avoids "no return" warnings
-            exit( exitCode );
     }
 
 } // namespace Catch
 
 #if defined ( CATCH_PLATFORM_WINDOWS ) /////////////////////////////////////////
 
+#define NOMINMAX
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#undef WIN32_LEAN_AND_MEAN
+#undef NOMINMAX
+
+
 namespace Catch {
 
+    struct SignalDefs { DWORD id; const char* name; };
+    extern SignalDefs signalDefs[];
+    // There is no 1-1 mapping between signals and windows exceptions.
+    // Windows can easily distinguish between SO and SigSegV,
+    // but SigInt, SigTerm, etc are handled differently.
+    SignalDefs signalDefs[] = {
+        { EXCEPTION_ILLEGAL_INSTRUCTION,  "SIGILL - Illegal instruction signal" },
+        { EXCEPTION_STACK_OVERFLOW, "SIGSEGV - Stack overflow" },
+        { EXCEPTION_ACCESS_VIOLATION, "SIGSEGV - Segmentation violation signal" },
+        { EXCEPTION_INT_DIVIDE_BY_ZERO, "Divide by zero error" },
+    };
+
     struct FatalConditionHandler {
-		void reset() {}
-	};
+
+        static LONG CALLBACK handleVectoredException(PEXCEPTION_POINTERS ExceptionInfo) {
+            for (int i = 0; i < sizeof(signalDefs) / sizeof(SignalDefs); ++i) {
+                if (ExceptionInfo->ExceptionRecord->ExceptionCode == signalDefs[i].id) {
+                    reportFatal(signalDefs[i].name, -i);
+                }
+            }
+            // If its not an exception we care about, pass it along.
+            // This stops us from eating debugger breaks etc.
+            return EXCEPTION_CONTINUE_SEARCH;
+        }
+
+        // 32k seems enough for Catch to handle stack overflow,
+        // but the value was found experimentally, so there is no strong guarantee
+        FatalConditionHandler():m_isSet(true), m_guaranteeSize(32 * 1024) {
+            // Register as first handler in current chain
+            AddVectoredExceptionHandler(1, handleVectoredException);
+            // Pass in guarantee size to be filled
+            SetThreadStackGuarantee(&m_guaranteeSize);
+        }
+
+        void reset() {
+            if (m_isSet) {
+                // Unregister handler and restore the old guarantee
+                RemoveVectoredExceptionHandler(handleVectoredException);
+                SetThreadStackGuarantee(&m_guaranteeSize);
+                m_isSet = false;
+            }
+        }
+
+        ~FatalConditionHandler() {
+            reset();
+        }
+    private:
+        bool m_isSet;
+        ULONG m_guaranteeSize;
+    };
 
 } // namespace Catch
 
@@ -40,7 +91,10 @@ namespace Catch {
 
 namespace Catch {
 
-    struct SignalDefs { int id; const char* name; };
+    struct SignalDefs {
+        int id;
+        const char* name;
+    };
     extern SignalDefs signalDefs[];
     SignalDefs signalDefs[] = {
             { SIGINT,  "SIGINT - Terminal interrupt signal" },
@@ -49,34 +103,67 @@ namespace Catch {
             { SIGSEGV, "SIGSEGV - Segmentation violation signal" },
             { SIGTERM, "SIGTERM - Termination request signal" },
             { SIGABRT, "SIGABRT - Abort (abnormal termination) signal" }
-        };
+    };
 
     struct FatalConditionHandler {
 
+        static bool isSet;
+        static struct sigaction oldSigActions [sizeof(signalDefs)/sizeof(SignalDefs)];
+        static stack_t oldSigStack;
+        static char altStackMem[SIGSTKSZ];
+    
         static void handleSignal( int sig ) {
-            for( std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i )
-                if( sig == signalDefs[i].id )
-                    fatal( signalDefs[i].name, -sig );
-            fatal( "<unknown signal>", -sig );
+            std::string name = "<unknown signal>";
+            for (std::size_t i = 0; i < sizeof(signalDefs) / sizeof(SignalDefs); ++i) {
+                SignalDefs &def = signalDefs[i];
+                if (sig == def.id) {
+                    name = def.name;
+                    break;
+                }
+            }
+            reset();
+            reportFatal(name, -sig);
+            raise( sig );
         }
 
-        FatalConditionHandler() : m_isSet( true ) {
-            for( std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i )
-                signal( signalDefs[i].id, handleSignal );
+        FatalConditionHandler() {
+            isSet = true;
+            stack_t sigStack;
+            sigStack.ss_sp = altStackMem;
+            sigStack.ss_size = SIGSTKSZ;
+            sigStack.ss_flags = 0;
+            sigaltstack(&sigStack, &oldSigStack);
+            struct sigaction sa = { 0 };
+
+            sa.sa_handler = handleSignal;
+            sa.sa_flags = SA_ONSTACK;
+            for (std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i) {
+                sigaction(signalDefs[i].id, &sa, &oldSigActions[i]);
+            }
         }
+                
+                
         ~FatalConditionHandler() {
             reset();
         }
-        void reset() {
-            if( m_isSet ) {
-                for( std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i )
-                    signal( signalDefs[i].id, SIG_DFL );
-                m_isSet = false;
+        static void reset() {
+            if( isSet ) {
+                // Set signals back to previous values -- hopefully nobody overwrote them in the meantime
+                for( std::size_t i = 0; i < sizeof(signalDefs)/sizeof(SignalDefs); ++i ) {
+                    sigaction(signalDefs[i].id, &oldSigActions[i], CATCH_NULL);
+                }
+                // Return the old stack
+                sigaltstack(&oldSigStack, CATCH_NULL);
+                isSet = false;
             }
         }
-
-        bool m_isSet;
     };
+    
+    bool FatalConditionHandler::isSet = false;
+    struct sigaction FatalConditionHandler::oldSigActions[sizeof(signalDefs)/sizeof(SignalDefs)] = {};
+    stack_t FatalConditionHandler::oldSigStack = {};
+    char FatalConditionHandler::altStackMem[SIGSTKSZ] = {};
+    
 
 } // namespace Catch