Fennel: AutoBacktrace Class Reference

List of all members.


Static Public Member Functions
static void	install (bool includeSegFault=true)
	Installs backtrace on error; default output is to stderr.
static void	setOutputStream (std::ostream &outStream)
	Sets an ostream to which the backtrace is written.
static void	setOutputStream ()
	Unsets a target stream for backtrace.
static void	setTraceTarget (SharedTraceTarget pTraceTarget=SharedTraceTarget())
	Sets a TraceTarget to which the backtrace is written, independent of setOutputStream.
Private Member Functions
	AutoBacktrace ()
Static Private Member Functions
static void	signal_handler (int signum)
static void	installSignal (int signum)
Static Private Attributes
static std::ostream *	pstream
static SharedTraceTarget	ptrace
static struct sigaction	nextAction [BACKTRACE_SIG_MAX]

Detailed Description

The backtrace handler has global scope. Fatal errors include abort(), assert(), fennel permAssert(), and runaway C++ exceptions.

Constructor & Destructor Documentation

AutoBacktrace::AutoBacktrace ( ) [inline, private]

Definition at line 132 of file Backtrace.h.

00133     {
00134     }

Member Function Documentation

void AutoBacktrace::signal_handler ( int signum ) [static, private]

Definition at line 198 of file Backtrace.cpp.

References TRACE_SEVERE.

Referenced by installSignal().

00199 {
00200 #ifndef __MSVC__
00201     Backtrace bt;
00202     if (ptrace) {
00203         std::ostringstream oss;
00204         oss <<
00205             "*** CAUGHT SIGNAL " << signum << "; BACKTRACE:" << std::endl;
00206         oss << bt;
00207         std::string msg = oss.str();
00208         if (pstream) {
00209             *pstream << msg;
00210         }
00211         ptrace->notifyTrace("backtrace", TRACE_SEVERE, msg);
00212     } else if (pstream) {
00213         *pstream <<
00214             "*** CAUGHT SIGNAL " << signum << "; BACKTRACE:" << std::endl;
00215         *pstream << bt;
00216     }
00217 
00218     // invoke next handler: never coming back, so reset the signal handler
00219     sigaction(signum, &(nextAction[signum]), NULL);
00220     raise(signum);
00221 #endif
00222 }

void AutoBacktrace::installSignal ( int signum ) [static, private]

Definition at line 256 of file Backtrace.cpp.

References nextAction, and signal_handler().

Referenced by install().

00257 {
00258 #ifndef __MSVC__
00259     permAssert(signum < BACKTRACE_SIG_MAX);
00260     struct sigaction act;
00261     struct sigaction old_act;
00262     act.sa_handler = signal_handler;
00263     sigemptyset (&act.sa_mask);
00264     act.sa_flags = 0;
00265     int rc = sigaction(signum, &act, &old_act);
00266     if (rc) {
00267         return;                         // failed
00268     }
00269     if (old_act.sa_handler != signal_handler) {
00270         // installed for the first time
00271         nextAction[signum] = old_act;
00272     }
00273 #endif
00274 }

void AutoBacktrace::install ( bool includeSegFault = true ) [static]

Installs backtrace on error; default output is to stderr.

NOTE jvs 25-Dec-2005: for more flexibility, we could allow the caller to specify a sigset_t.

Parameters:

includeSegFault

if true, SIGSEGV is included in the set of signals causing a backtrace; if false, it is omitted (required in environments such as a Java VM where spurious segfaults may be signalled but handled as part of normal operation)

Definition at line 239 of file Backtrace.cpp.

References installSignal().

Referenced by TestBase::beforeTestCase(), and JniUtil::init().

00240 {
00241     // Traps SIGABRT: this handles assert(); unless NDEBUG, permAssert() =>
00242     // assert(), so that's covered. std::terminate() also => abort().  TODO:
00243     // trap permAssert() directly.
00244 #ifndef __MSVC__
00245     installSignal(SIGILL);
00246     installSignal(SIGABRT);
00247 
00248     if (includeSegFault) {
00249         installSignal(SIGSEGV);
00250     }
00251 
00252     installSignal(SIGBUS);
00253 #endif
00254 }