PrettyStackTrace.cpp revision 195098
1//===- PrettyStackTrace.cpp - Pretty Crash Handling -----------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines some helpful functions for dealing with the possibility of 11// Unix signals occuring while your program is running. 12// 13//===----------------------------------------------------------------------===// 14 15#include "llvm/Support/PrettyStackTrace.h" 16#include "llvm/Support/raw_ostream.h" 17#include "llvm/System/Signals.h" 18#include "llvm/System/ThreadLocal.h" 19#include "llvm/ADT/SmallString.h" 20using namespace llvm; 21 22// FIXME: This should be thread local when llvm supports threads. 23static sys::ThreadLocal<const PrettyStackTraceEntry> PrettyStackTraceHead; 24 25static unsigned PrintStack(const PrettyStackTraceEntry *Entry, raw_ostream &OS){ 26 unsigned NextID = 0; 27 if (Entry->getNextEntry()) 28 NextID = PrintStack(Entry->getNextEntry(), OS); 29 OS << NextID << ".\t"; 30 Entry->print(OS); 31 32 return NextID+1; 33} 34 35/// PrintCurStackTrace - Print the current stack trace to the specified stream. 36static void PrintCurStackTrace(raw_ostream &OS) { 37 // Don't print an empty trace. 38 if (PrettyStackTraceHead.get() == 0) return; 39 40 // If there are pretty stack frames registered, walk and emit them. 41 OS << "Stack dump:\n"; 42 43 PrintStack(PrettyStackTraceHead.get(), OS); 44 OS.flush(); 45} 46 47// Integrate with crash reporter. 48#ifdef __APPLE__ 49extern "C" const char *__crashreporter_info__; 50const char *__crashreporter_info__ = 0; 51#endif 52 53 54/// CrashHandler - This callback is run if a fatal signal is delivered to the 55/// process, it prints the pretty stack trace. 56static void CrashHandler(void *Cookie) { 57#ifndef __APPLE__ 58 // On non-apple systems, just emit the crash stack trace to stderr. 59 PrintCurStackTrace(errs()); 60#else 61 // Otherwise, emit to a smallvector of chars, send *that* to stderr, but also 62 // put it into __crashreporter_info__. 63 SmallString<2048> TmpStr; 64 { 65 raw_svector_ostream Stream(TmpStr); 66 PrintCurStackTrace(Stream); 67 } 68 69 if (!TmpStr.empty()) { 70 __crashreporter_info__ = strdup(TmpStr.c_str()); 71 errs() << __crashreporter_info__; 72 } 73 74#endif 75} 76 77static bool RegisterCrashPrinter() { 78 sys::AddSignalHandler(CrashHandler, 0); 79 return false; 80} 81 82PrettyStackTraceEntry::PrettyStackTraceEntry() { 83 // The first time this is called, we register the crash printer. 84 static bool HandlerRegistered = RegisterCrashPrinter(); 85 HandlerRegistered = HandlerRegistered; 86 87 // Link ourselves. 88 NextEntry = PrettyStackTraceHead.get(); 89 PrettyStackTraceHead.set(this); 90} 91 92PrettyStackTraceEntry::~PrettyStackTraceEntry() { 93 assert(PrettyStackTraceHead.get() == this && 94 "Pretty stack trace entry destruction is out of order"); 95 PrettyStackTraceHead.set(getNextEntry()); 96} 97 98void PrettyStackTraceString::print(raw_ostream &OS) const { 99 OS << Str << "\n"; 100} 101 102void PrettyStackTraceProgram::print(raw_ostream &OS) const { 103 OS << "Program arguments: "; 104 // Print the argument list. 105 for (unsigned i = 0, e = ArgC; i != e; ++i) 106 OS << ArgV[i] << ' '; 107 OS << '\n'; 108} 109 110