pap2k/tracey

Tracey is a lightweight and simple C++11 memory leak finder with no dependencies.

tracey

• Lightweight and simple memory C++11 leak finder (requires std::mutex, std::thread)
• Easy to integrate. No source modification is required.
• Clean. Macroless and callstack based. No new/delete macro hacks.
• Lazy. Should work out of the box. Plenty configuration options are provided anyways.
• Tiny. One header and one source file.
• Cross-platform. OS dependencies only. No third party dependencies.
• MIT licensed.

Implementation directives (optional)

• kTraceyAlloc(size) defaults to std::malloc(size) if not overriden.
  • All allocations merge to this symbol.
• kTraceyFree(ptr) defaults to std::free(ptr) if not overriden.
  • All deallocations merge to this symbol.
• kTraceyPrint(str) defaults to fprintf(stderr,"%s",str) if not overriden.
  • All warning and reports merge to this symbol.
• kTraceyAssert(expr) defaults to assert(expr) if not overriden.
  • All out-of-memory runtime asserts merge to this symbol.
• kTraceyBadAlloc() defaults to std::bad_alloc() if not overriden.
  • All out-of-memory runtime exceptions merge to this sysmbol.

Configuration directives (optional)

• kTraceyAllocMultiplier defaults to 1.0 if not overriden (should be >= 1.0).
  • Tracey uses this value to increase memory requirements, and to simulate and to debug worse memory conditions.
• kTraceyReportWildPointers defaults to 1 if not overriden (should be 0 or 1).
  • When enabled, Tracey warns about deallocations on pointers that have been not allocated by Tracey (wild pointers).
• kTraceyReportNullPointers defaults to 0 if not overriden (should be 0 or 1).
  • When enabled, Tracey warns about deallocations on null pointers.
• kTraceyEnabledOnStart defaults to 1 if not overriden (should be 0 or 1).
  • When enabled, Tracey starts before application is running.
• kTraceyReportOnExit defaults to 1 if not overriden (should be 0 or 1).
  • When enabled, Tracey shows a report automatically on application exit.
• kTraceyDefineMemoryOperators defaults to 1 if not overriden (should be 0 or 1).
  • When enabled, Tracey implements all new([])/delete([]) operators.
  • When disabled, user must provide de/allocation operators thru runtime API (see below).

Runtime API (optional)

• tracey::watch() tells Tracey to watch a memory address.
• tracey::forget() tells Tracey to forget about a memory address.
• tracey::enable() tells Tracey to enable/disable whole watching system.
• tracey::disable() tells Tracey to disable whole watching system.
• tracey::is_enabled() returns Tracey's working status.
• tracey::invalidate() tells Tracey to forget whole execution.
• tracey::report() tells Tracey to show current report.
• tracey::version() tells Tracey to return current version.

Sample

// tracey is callstack based. no dirty new/delete macro tricks.
// tracey is a static library. requires no source modification. just link it.

void *make_leaks()
{
    return new int [400];
}

int main( int argc, const char **argv )
{
    int *make_leak = new int();
    make_leaks();

    return 0;
}

Possible output

D:\prj\tracey>cl sample.cc tracey.cpp /MD /Zi -DkTraceyReportOnExit=1
D:\prj\tracey>sample
<tracey/tracey.cpp> says: Beginning of report. Error, 2 leaks found; 1604 bytes wasted ('lame' score)
1) Leak 4 bytes [0033F1E8] backtrace 1/2 (50%)
        main (d:\prj\moons\tracey\sample.cc, line 11)
        __tmainCRTStartup (f:\dd\vctools\crt_bld\self_x86\crt\src\crtexe.c, line 536)
        mainCRTStartup (f:\dd\vctools\crt_bld\self_x86\crt\src\crtexe.c, line 377)
        BaseThreadInitThunk
        RtlInitializeExceptionChain
        RtlInitializeExceptionChain
2) Leak 1600 bytes [0035D8E8] backtrace 2/2 (100%)
        make_leaks (d:\prj\moons\tracey\sample.cc, line 6)
        main (d:\prj\moons\tracey\sample.cc, line 14)
        __tmainCRTStartup (f:\dd\vctools\crt_bld\self_x86\crt\src\crtexe.c, line 536)
        mainCRTStartup (f:\dd\vctools\crt_bld\self_x86\crt\src\crtexe.c, line 377)
        BaseThreadInitThunk
        RtlInitializeExceptionChain
        RtlInitializeExceptionChain
<tracey/tracey.cpp> says: End of report. Error, 2 leaks found; 1604 bytes wasted ('lame' score)
D:\prj\tracey>