Changeset 165 for Evidence

Timestamp:

02/09/10 06:49:45 (15 years ago)

Author:

ogrimm

Message:

Improved C++ unhandled exception handling

Location:

Evidence

Files:

• Evidence.cc (modified) (4 diffs)
• Evidence.h (modified) (2 diffs)

Evidence/Evidence.cc

@@ -15 +15 @@
   - The static method ToString() converts the contents of a
     DIMInfo service into text
-        
+  - A terminate-handler is installed for catching unhandled C++ exceptions.
+  
   All memory allocated by the non-static methods will be freed by the
   class destructor.
   
-  Oliver Grimm, December 2009
+  Oliver Grimm, February 2009
  
 \********************************************************************/
@@ -51 +52 @@
   
   // Start server
-  static char Init[] = "Server started (" EVIDENCE_REVISION "  Compiled "__DATE__ __TIME__ ")";
-  Status = new DimService((string(Name) + "/Status").c_str(), (char *) "C", Init, sizeof(Init));
+  string Rev(EVIDENCE_REVISION);
+  Rev = Rev.substr(1, Rev.size()-3);
+  if (asprintf(&InitMsg, "Server started (%s, compiled %s)", Rev.c_str(),__TIMESTAMP__) == -1) InitMsg = NULL;
+  
+  Status = new DimService((string(Name) + "/Status").c_str(), (char *) "C", InitMsg, strlen(InitMsg)+1);
 
   start(Name);
@@ -61 +65 @@
 EvidenceServer::~EvidenceServer() {
 
+  free(InitMsg);
   State(INFO, "Server stopped");
   
@@ -182 +187 @@
 }
 
-// C++ exception handler
+// C++ exception handler (derived from gcc __verbose_terminate_handler())
 void EvidenceServer::Terminate() {
 
-  string Msg = string(ThisServer->Status->getName()) + ": Caught unhandled exception";
-
-  printf("%s\n", Msg.c_str());
-  DimClient::sendCommand("DColl/Log", Msg.c_str());
-  
-  abort();
+  static char Msg[STATUS_SIZE];
+  static bool Terminating = false;
+
+  if (Terminating) {
+        snprintf(Msg, sizeof(Msg), "%s: Terminate() called recursively, calling abort()", ThisServer->Status->getName());
+        printf("%s\n", Msg);
+        DimClient::sendCommandNB("DColl/Log", Msg);
+        abort();
+  }
+  else {
+        Terminating = true;
+
+        // Make sure there was an exception; terminate is also called for an
+        // attempt to rethrow when there is no suitable exception.
+        type_info *Type = abi::__cxa_current_exception_type();
+        if (Type != NULL) {
+          int Status = -1;
+          char *Demangled = NULL;
+
+          Demangled = abi::__cxa_demangle(Type->name(), 0, 0, &Status);
+          snprintf(Msg, sizeof(Msg), "%s: Terminate() called after throwing an instance of '%s'", ThisServer->Status->getName(), Status==0 ? Demangled : Type->name());
+          free(Demangled);
+
+          // If exception derived from std::exception, more information.
+          try { __throw_exception_again; }
+          catch (exception &E) {
+                snprintf(Msg+strlen(Msg), sizeof(Msg)-strlen(Msg), " (what(): %s)", E.what());    
+          }
+          catch (...) { }
+        }
+        else snprintf(Msg, sizeof(Msg), "%s: Terminate() called without an active exception", ThisServer->Status->getName());
+  }
+
+  ThisServer->State(FATAL, Msg);
 }
 

Evidence/Evidence.h

@@ -6 +6 @@
 #include <string>
 #include <errno.h>
+#include <vector>
 #include <exception>
-#include <vector>
- 
+#include <cxxabi.h>
+
 #include "dis.hxx"
 #include "dic.hxx"
@@ -28 +29 @@
 
     DimService *Status;
+        char *InitMsg;
 
     static void SignalHandler(int); // static for signal()