1 //===- llvm/Support/PrettyStackTrace.h - Pretty Crash Handling --*- C++ -*-===// 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 the PrettyStackTraceEntry class, which is used to make 11 // crashes give more contextual information about what the program was doing 12 // when it crashed. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_SUPPORT_PRETTYSTACKTRACE_H 17 #define LLVM_SUPPORT_PRETTYSTACKTRACE_H 18 19 #include "llvm/Support/Compiler.h" 20 21 namespace llvm { 22 class raw_ostream; 23 24 void EnablePrettyStackTrace(); 25 26 /// PrettyStackTraceEntry - This class is used to represent a frame of the 27 /// "pretty" stack trace that is dumped when a program crashes. You can define 28 /// subclasses of this and declare them on the program stack: when they are 29 /// constructed and destructed, they will add their symbolic frames to a 30 /// virtual stack trace. This gets dumped out if the program crashes. 31 class PrettyStackTraceEntry { 32 const PrettyStackTraceEntry *NextEntry; 33 PrettyStackTraceEntry(const PrettyStackTraceEntry &) = delete; 34 void operator=(const PrettyStackTraceEntry&) = delete; 35 public: 36 PrettyStackTraceEntry(); 37 virtual ~PrettyStackTraceEntry(); 38 39 /// print - Emit information about this stack frame to OS. 40 virtual void print(raw_ostream &OS) const = 0; 41 42 /// getNextEntry - Return the next entry in the list of frames. 43 const PrettyStackTraceEntry *getNextEntry() const { return NextEntry; } 44 }; 45 46 /// PrettyStackTraceString - This object prints a specified string (which 47 /// should not contain newlines) to the stream as the stack trace when a crash 48 /// occurs. 49 class PrettyStackTraceString : public PrettyStackTraceEntry { 50 const char *Str; 51 public: 52 PrettyStackTraceString(const char *str) : Str(str) {} 53 void print(raw_ostream &OS) const override; 54 }; 55 56 /// PrettyStackTraceProgram - This object prints a specified program arguments 57 /// to the stream as the stack trace when a crash occurs. 58 class PrettyStackTraceProgram : public PrettyStackTraceEntry { 59 int ArgC; 60 const char *const *ArgV; 61 public: 62 PrettyStackTraceProgram(int argc, const char * const*argv) 63 : ArgC(argc), ArgV(argv) { 64 EnablePrettyStackTrace(); 65 } 66 void print(raw_ostream &OS) const override; 67 }; 68 69 /// Returns the topmost element of the "pretty" stack state. 70 const void* SavePrettyStackState(); 71 72 /// Restores the topmost element of the "pretty" stack state to State, which 73 /// should come from a previous call to SavePrettyStackState(). This is 74 /// useful when using a CrashRecoveryContext in code that also uses 75 /// PrettyStackTraceEntries, to make sure the stack that's printed if a crash 76 /// happens after a crash that's been recovered by CrashRecoveryContext 77 /// doesn't have frames on it that were added in code unwound by the 78 /// CrashRecoveryContext. 79 void RestorePrettyStackState(const void* State); 80 81 } // end namespace llvm 82 83 #endif 84
