DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Implementation

Mercurial (c68fe15a81fc)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* APIs for getting a stack trace of the current thread */

#ifndef mozilla_StackWalk_h
#define mozilla_StackWalk_h

#include "mozilla/Types.h"
#include <stdint.h>

/**
 * The callback for MozStackWalk and MozStackWalkThread.
 *
 * @param aFrameNumber  The frame number (starts at 1, not 0).
 * @param aPC           The program counter value.
 * @param aSP           The best approximation possible of what the stack
 *                      pointer will be pointing to when the execution returns
 *                      to executing that at aPC. If no approximation can
 *                      be made it will be nullptr.
 * @param aClosure      Extra data passed in from MozStackWalk() or
 *                      MozStackWalkThread().
 */
typedef void (*MozWalkStackCallback)(uint32_t aFrameNumber, void* aPC,
                                     void* aSP, void* aClosure);

/**
 * Call aCallback for each stack frame on the current thread, from
 * the caller of MozStackWalk to main (or above).
 *
 * @param aCallback    Callback function, called once per frame.
 * @param aSkipFrames  Number of initial frames to skip.  0 means that
 *                     the first callback will be for the caller of
 *                     MozStackWalk.
 * @param aMaxFrames   Maximum number of frames to trace.  0 means no limit.
 * @param aClosure     Caller-supplied data passed through to aCallback.
 *
 * May skip some stack frames due to compiler optimizations or code
 * generation.
 */
MFBT_API void MozStackWalk(MozWalkStackCallback aCallback, uint32_t aSkipFrames,
                           uint32_t aMaxFrames, void* aClosure);

#if defined(_WIN32) && (defined(_M_IX86) || defined(_M_AMD64) || \
                        defined(_M_IA64) || defined(_M_ARM64))

#  include <windows.h>

#  define MOZ_STACKWALK_SUPPORTS_WINDOWS 1

/**
 * Like MozStackWalk, but walks the stack for another thread.
 * Call aCallback for each stack frame on the current thread, from
 * the caller of MozStackWalk to main (or above).
 *
 * @param aCallback    Same as for MozStackWalk().
 * @param aSkipFrames  Same as for MozStackWalk().
 * @param aMaxFrames   Same as for MozStackWalk().
 * @param aClosure     Same as for MozStackWalk().
 * @param aThread      The handle of the thread whose stack is to be walked.
 *                     If 0, walks the current thread.
 * @param aContext     A CONTEXT, presumably obtained with GetThreadContext()
 *                     after suspending the thread with SuspendThread(). If
 *                     null, the CONTEXT will be re-obtained.
 */
MFBT_API void MozStackWalkThread(MozWalkStackCallback aCallback,
                                 uint32_t aSkipFrames, uint32_t aMaxFrames,
                                 void* aClosure, HANDLE aThread,
                                 CONTEXT* aContext);

#else

#  define MOZ_STACKWALK_SUPPORTS_WINDOWS 0

#endif

typedef struct {
  /*
   * The name of the shared library or executable containing an
   * address and the address's offset within that library, or empty
   * string and zero if unknown.
   */
  char library[256];
  ptrdiff_t loffset;
  /*
   * The name of the file name and line number of the code
   * corresponding to the address, or empty string and zero if
   * unknown.
   */
  char filename[256];
  unsigned long lineno;
  /*
   * The name of the function containing an address and the address's
   * offset within that function, or empty string and zero if unknown.
   */
  char function[256];
  ptrdiff_t foffset;
} MozCodeAddressDetails;

/**
 * For a given pointer to code, fill in the pieces of information used
 * when printing a stack trace.
 *
 * @param aPC         The code address.
 * @param aDetails    A structure to be filled in with the result.
 */
MFBT_API bool MozDescribeCodeAddress(void* aPC,
                                     MozCodeAddressDetails* aDetails);

/**
 * Format the information about a code address in a format suitable for
 * stack traces on the current platform.  When available, this string
 * should contain the function name, source file, and line number.  When
 * these are not available, library and offset should be reported, if
 * possible.
 *
 * Note that this output is parsed by several scripts including the fix*.py and
 * make-tree.pl scripts in tools/rb/. It should only be change with care, and
 * in conjunction with those scripts.
 *
 * @param aBuffer      A string to be filled in with the description.
 *                     The string will always be null-terminated.
 * @param aBufferSize  The size, in bytes, of aBuffer, including
 *                     room for the terminating null.  If the information
 *                     to be printed would be larger than aBuffer, it
 *                     will be truncated so that aBuffer[aBufferSize-1]
 *                     is the terminating null.
 * @param aFrameNumber The frame number.
 * @param aPC          The code address.
 * @param aFunction    The function name. Possibly null or the empty string.
 * @param aLibrary     The library name. Possibly null or the empty string.
 * @param aLOffset     The library offset.
 * @param aFileName    The filename. Possibly null or the empty string.
 * @param aLineNo      The line number. Possibly zero.
 */
MFBT_API void MozFormatCodeAddress(char* aBuffer, uint32_t aBufferSize,
                                   uint32_t aFrameNumber, const void* aPC,
                                   const char* aFunction, const char* aLibrary,
                                   ptrdiff_t aLOffset, const char* aFileName,
                                   uint32_t aLineNo);

/**
 * Format the information about a code address in the same fashion as
 * MozFormatCodeAddress.
 *
 * @param aBuffer      A string to be filled in with the description.
 *                     The string will always be null-terminated.
 * @param aBufferSize  The size, in bytes, of aBuffer, including
 *                     room for the terminating null.  If the information
 *                     to be printed would be larger than aBuffer, it
 *                     will be truncated so that aBuffer[aBufferSize-1]
 *                     is the terminating null.
 * @param aFrameNumber The frame number.
 * @param aPC          The code address.
 * @param aDetails     The value filled in by MozDescribeCodeAddress(aPC).
 */
MFBT_API void MozFormatCodeAddressDetails(
    char* aBuffer, uint32_t aBufferSize, uint32_t aFrameNumber, void* aPC,
    const MozCodeAddressDetails* aDetails);

namespace mozilla {

MFBT_API void FramePointerStackWalk(MozWalkStackCallback aCallback,
                                    uint32_t aSkipFrames, uint32_t aMaxFrames,
                                    void* aClosure, void** aBp,
                                    void* aStackEnd);

#if defined(XP_LINUX) || defined(XP_FREEBSD)
MFBT_API void DemangleSymbol(const char* aSymbol, char* aBuffer, int aBufLen);
#endif

}  // namespace mozilla

#endif