1 //===- llvm/Support/PrettyStackTrace.h - Pretty Crash Handling --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the PrettyStackTraceEntry class, which is used to make
11 // crashes give more contextual information about what the program was doing
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_SUPPORT_PRETTYSTACKTRACE_H
17 #define LLVM_SUPPORT_PRETTYSTACKTRACE_H
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/Support/Compiler.h"
25 void EnablePrettyStackTrace();
27 /// PrettyStackTraceEntry - This class is used to represent a frame of the
28 /// "pretty" stack trace that is dumped when a program crashes. You can define
29 /// subclasses of this and declare them on the program stack: when they are
30 /// constructed and destructed, they will add their symbolic frames to a
31 /// virtual stack trace. This gets dumped out if the program crashes.
32 class PrettyStackTraceEntry {
33 friend PrettyStackTraceEntry *ReverseStackTrace(PrettyStackTraceEntry *);
35 PrettyStackTraceEntry *NextEntry;
36 PrettyStackTraceEntry(const PrettyStackTraceEntry &) = delete;
37 void operator=(const PrettyStackTraceEntry &) = delete;
39 PrettyStackTraceEntry();
40 virtual ~PrettyStackTraceEntry();
42 /// print - Emit information about this stack frame to OS.
43 virtual void print(raw_ostream &OS) const = 0;
45 /// getNextEntry - Return the next entry in the list of frames.
46 const PrettyStackTraceEntry *getNextEntry() const { return NextEntry; }
49 /// PrettyStackTraceString - This object prints a specified string (which
50 /// should not contain newlines) to the stream as the stack trace when a crash
52 class PrettyStackTraceString : public PrettyStackTraceEntry {
55 PrettyStackTraceString(const char *str) : Str(str) {}
56 void print(raw_ostream &OS) const override;
59 /// PrettyStackTraceFormat - This object prints a string (which may use
60 /// printf-style formatting but should not contain newlines) to the stream
61 /// as the stack trace when a crash occurs.
62 class PrettyStackTraceFormat : public PrettyStackTraceEntry {
63 llvm::SmallVector<char, 32> Str;
65 PrettyStackTraceFormat(const char *Format, ...);
66 void print(raw_ostream &OS) const override;
69 /// PrettyStackTraceProgram - This object prints a specified program arguments
70 /// to the stream as the stack trace when a crash occurs.
71 class PrettyStackTraceProgram : public PrettyStackTraceEntry {
73 const char *const *ArgV;
75 PrettyStackTraceProgram(int argc, const char * const*argv)
76 : ArgC(argc), ArgV(argv) {
77 EnablePrettyStackTrace();
79 void print(raw_ostream &OS) const override;
82 /// Returns the topmost element of the "pretty" stack state.
83 const void *SavePrettyStackState();
85 /// Restores the topmost element of the "pretty" stack state to State, which
86 /// should come from a previous call to SavePrettyStackState(). This is
87 /// useful when using a CrashRecoveryContext in code that also uses
88 /// PrettyStackTraceEntries, to make sure the stack that's printed if a crash
89 /// happens after a crash that's been recovered by CrashRecoveryContext
90 /// doesn't have frames on it that were added in code unwound by the
91 /// CrashRecoveryContext.
92 void RestorePrettyStackState(const void *State);
94 } // end namespace llvm