Changeset bffcd66

Timestamp:

Dec 16, 2019, 2:31:10 PM (5 years ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

6f9cc13

Parents:

07de76b

Message:

harmonize signal handling in main.cc with interpose.cfa, consider refactoring all signal code into a separate module

File:

• src/main.cc (modified) (11 diffs)

src/main.cc

@@ -10 +10 @@
 // Created On       : Fri May 15 23:12:02 2015
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Fri Aug 23 06:50:08 2019
-// Update Count     : 607
+// Last Modified On : Fri Dec 13 23:47:06 2019
+// Update Count     : 626
 //
 
@@ -20 +20 @@
 #include <cstdio>                           // for fopen, FILE, fclose, stdin
 #include <cstdlib>                          // for exit, free, abort, EXIT_F...
-#include <csignal>                         // for signal, SIGABRT, SIGSEGV
+#include <csignal>                          // for signal, SIGABRT, SIGSEGV
 #include <cstring>                          // for index
 #include <fstream>                          // for ofstream
@@ -28 +28 @@
 #include <list>                             // for list
 #include <string>                           // for char_traits, operator<<
+
+using namespace std;
+
 
 #include "CompilationState.h"
@@ -53 +56 @@
 #include "InitTweak/GenInit.h"              // for genInit
 #include "MakeLibCfa.h"                     // for makeLibCfa
-#include "Parser/LinkageSpec.h"             // for Spec, Cforall, Intrinsic
 #include "Parser/ParseNode.h"               // for DeclarationNode, buildList
 #include "Parser/TypedefTable.h"            // for TypedefTable
@@ -59 +61 @@
 #include "ResolvExpr/Resolver.h"            // for resolve
 #include "SymTab/Validate.h"                // for validate
+#include "SynTree/LinkageSpec.h"            // for Spec, Cforall, Intrinsic
 #include "SynTree/Declaration.h"            // for Declaration
 #include "SynTree/Visitor.h"                // for acceptAll
@@ -64 +67 @@
 #include "Virtual/ExpandCasts.h"            // for expandCasts
 
-
-using namespace std;
 
 static void NewPass( const char * const name ) {
@@ -97 +98 @@
 static bool waiting_for_gdb = false;                                    // flag to set cfa-cpp to wait for gdb on start
 
-static std::string PreludeDirector = "";
+static string PreludeDirector = "";
 
 static void parse_cmdline( int argc, char *argv[] );
@@ -153 +154 @@
 } // backtrace
 
-static void sigSegvBusHandler( int sig_num ) {
-        cerr << "*CFA runtime error* program cfa-cpp terminated with "
-                 <<     (sig_num == SIGSEGV ? "segment fault" : "bus error")
-                 << "." << endl;
+#define SIGPARMS int sig __attribute__(( unused )), siginfo_t * sfp __attribute__(( unused )), ucontext_t * cxt __attribute__(( unused ))
+
+static void Signal( int sig, void (*handler)(SIGPARMS), int flags ) {
+        struct sigaction act;
+
+        act.sa_sigaction = (void (*)(int, siginfo_t *, void *))handler;
+        sigemptyset( &act.sa_mask );
+        sigaddset( &act.sa_mask, SIGALRM );                                     // disabled during signal handler
+        sigaddset( &act.sa_mask, SIGUSR1 );
+        act.sa_flags = flags;
+
+        if ( sigaction( sig, &act, nullptr ) == -1 ) {
+            cerr << "*CFA runtime error* problem installing signal handler, error(" << errno << ") " << strerror( errno ) << endl;
+            _exit( EXIT_FAILURE );
+        } // if
+} // Signal
+
+static void sigSegvBusHandler( SIGPARMS ) {
+        if ( sfp->si_addr == nullptr ) {
+                cerr << "Null pointer (nullptr) dereference." << endl;
+        } else {
+                cerr << (sig == SIGSEGV ? "Segment fault" : "Bus error") << " at memory location " << sfp->si_addr << "." << endl
+                         << "Possible cause is reading outside the address space or writing to a protected area within the address space with an invalid pointer or subscript." << endl;
+        } // if
         backtrace( 2 );                                                                         // skip first 2 stack frames
-        //_exit( EXIT_FAILURE );
         abort();                                                                                        // cause core dump for debugging
 } // sigSegvBusHandler
 
-static void sigAbortHandler( __attribute__((unused)) int sig_num ) {
+static void sigAbortHandler( SIGPARMS ) {
         backtrace( 6 );                                                                         // skip first 6 stack frames
-        signal( SIGABRT, SIG_DFL);                                                      // reset default signal handler
+        Signal( SIGABRT, (void (*)(SIGPARMS))SIG_DFL, SA_SIGINFO );     // reset default signal handler
         raise( SIGABRT );                                                                       // reraise SIGABRT
 } // sigAbortHandler
@@ -173 +193 @@
         list< Declaration * > translationUnit;
 
-        signal( SIGSEGV, sigSegvBusHandler );
-        signal( SIGBUS, sigSegvBusHandler );
-        signal( SIGABRT, sigAbortHandler );
-
-        // std::cout << "main" << std::endl;
+        Signal( SIGSEGV, sigSegvBusHandler, SA_SIGINFO );
+        Signal( SIGBUS, sigSegvBusHandler, SA_SIGINFO );
+        Signal( SIGABRT, sigAbortHandler, SA_SIGINFO );
+
+        // cout << "main" << endl;
         // for ( int i = 0; i < argc; i += 1 ) {
-        //      std::cout << '\t' << argv[i] << std::endl;
+        //      cout << '\t' << argv[i] << endl;
         // } // for
 
@@ -186 +206 @@
 
         if ( waiting_for_gdb ) {
-                std::cerr << "Waiting for gdb" << std::endl;
-                std::cerr << "run :" << std::endl;
-                std::cerr << "  gdb attach " << getpid() << std::endl;
+                cerr << "Waiting for gdb" << endl;
+                cerr << "run :" << endl;
+                cerr << "  gdb attach " << getpid() << endl;
                 raise(SIGSTOP);
         } // if
@@ -388 +408 @@
                 return EXIT_FAILURE;
         } catch ( ... ) {
-                std::exception_ptr eptr = std::current_exception();
+                exception_ptr eptr = current_exception();
                 try {
                         if (eptr) {
-                                std::rethrow_exception(eptr);
+                                rethrow_exception(eptr);
                         } else {
-                                std::cerr << "Exception Uncaught and Unknown" << std::endl;
-                        } // if
-                } catch(const std::exception& e) {
-                        std::cerr << "Uncaught Exception \"" << e.what() << "\"\n";
+                                cerr << "Exception Uncaught and Unknown" << endl;
+                        } // if
+                } catch(const exception& e) {
+                        cerr << "Uncaught Exception \"" << e.what() << "\"\n";
                 } // try
                 return EXIT_FAILURE;