Merge pull request #74 from CyberShadow/manual-backtrace

When backtrace() fails, perform a manual backtrace.
dlang · Sep 24, 2011 · 7134f38 · 7134f38
2 parents 9270d5a + 621a2b5
commit 7134f38
Showing 1 changed file with 34 additions and 3 deletions.
diff --git a/src/core/runtime.d b/src/core/runtime.d
@@ -36,6 +36,8 @@ private
     extern (C) void* rt_loadLibrary( in char[] name );
     extern (C) bool  rt_unloadLibrary( void* ptr );
 
+    extern (C) void* rt_stackBottom();
+
     extern (C) string[] rt_args();
 
     version( linux )
@@ -395,8 +397,33 @@ Throwable.TraceInfo defaultTraceHandler( void* ptr = null )
             {
                 static enum MAXFRAMES = 128;
                 void*[MAXFRAMES]  callstack;
-
                 numframes = backtrace( callstack, MAXFRAMES );
+                if (numframes < 2) // backtrace() failed, do it ourselves
+                {
+                    static void** getBasePtr()
+                    {
+                        version( D_InlineAsm_X86 )
+                            asm { naked; mov EAX, EBP; ret; }
+                        else
+                        version( D_InlineAsm_X86_64 )
+                            asm { naked; mov RAX, RBP; ret; }
+                        else
+                            return null;
+                    }
+
+                    void** stackTop = getBasePtr(), stackBottom = cast(void**)rt_stackBottom();
+                    void* dummy;
+                    if (stackTop && &dummy < stackTop && stackTop < stackBottom)
+                    {
+                        void** stackPtr = stackTop;
+                        numframes = 0;
+                        while (stackTop <= stackPtr && stackPtr < stackBottom && numframes < MAXFRAMES)
+                        {
+                            callstack[numframes++] = *(stackPtr+1);
+                            stackPtr = cast(void**)*stackPtr;
+                        }
+                    }
+                }
                 framelist = backtrace_symbols( callstack, numframes );
             }
 
@@ -490,10 +517,14 @@ Throwable.TraceInfo defaultTraceHandler( void* ptr = null )
                 }
                 else version( linux )
                 {
-                    // format is:
-                    // module(_D6module4funcAFZv) [0x00000000]
+                    // format is:  module(_D6module4funcAFZv) [0x00000000]
+                    // or:         module(_D6module4funcAFZv+0x78) [0x00000000]
                     auto bptr = cast(char*) memchr( buf.ptr, '(', buf.length );
                     auto eptr = cast(char*) memchr( buf.ptr, ')', buf.length );
+                    auto pptr = cast(char*) memchr( buf.ptr, '+', buf.length );
+
+                    if (pptr && pptr < eptr)
+                        eptr = pptr;
 
                     if( bptr++ && eptr )
                     {