// Copyright (c) 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// ---
// Author: Sanjay Ghemawat
//
// Routines to extract the current stack trace. These functions are
// thread-safe.
#ifndef GOOGLE_STACKTRACE_H_
#define GOOGLE_STACKTRACE_H_
// Annoying stuff for windows -- makes sure clients can import these functions
#ifndef PERFTOOLS_DLL_DECL
# ifdef _WIN32
# define PERFTOOLS_DLL_DECL __declspec(dllimport)
# else
# define PERFTOOLS_DLL_DECL
# endif
#endif
// Skips the most recent "skip_count" stack frames (also skips the
// frame generated for the "GetStackFrames" routine itself), and then
// records the pc values for up to the next "max_depth" frames in
// "result", and the corresponding stack frame sizes in "sizes".
// Returns the number of values recorded in "result"/"sizes".
//
// Example:
// main() { foo(); }
// foo() { bar(); }
// bar() {
// void* result[10];
// int sizes[10];
// int depth = GetStackFrames(result, sizes, 10, 1);
// }
//
// The GetStackFrames call will skip the frame for "bar". It will
// return 2 and will produce pc values that map to the following
// procedures:
// result[0] foo
// result[1] main
// (Actually, there may be a few more entries after "main" to account for
// startup procedures.)
// And corresponding stack frame sizes will also be recorded:
// sizes[0] 16
// sizes[1] 16
// (Stack frame sizes of 16 above are just for illustration purposes.)
// Stack frame sizes of 0 or less indicate that those frame sizes couldn't
// be identified.
//
// This routine may return fewer stack frame entries than are
// available. Also note that "result" and "sizes" must both be non-NULL.
extern PERFTOOLS_DLL_DECL int GetStackFrames(void** result, int* sizes, int max_depth,
int skip_count);
// Same as above, but to be used from a signal handler. The "uc" parameter
// should be the pointer to ucontext_t which was passed as the 3rd parameter
// to sa_sigaction signal handler. It may help the unwinder to get a
// better stack trace under certain conditions. The "uc" may safely be NULL.
extern PERFTOOLS_DLL_DECL int GetStackFramesWithContext(void** result, int* sizes, int max_depth,
int skip_count, const void *uc);
// This is similar to the GetStackFrames routine, except that it returns
// the stack trace only, and not the stack frame sizes as well.
// Example:
// main() { foo(); }
// foo() { bar(); }
// bar() {
// void* result[10];
// int depth = GetStackTrace(result, 10, 1);
// }
//
// This produces:
// result[0] foo
// result[1] main
// .... ...
//
// "result" must not be NULL.
extern PERFTOOLS_DLL_DECL int GetStackTrace(void** result, int max_depth,
int skip_count);
// Same as above, but to be used from a signal handler. The "uc" parameter
// should be the pointer to ucontext_t which was passed as the 3rd parameter
// to sa_sigaction signal handler. It may help the unwinder to get a
// better stack trace under certain conditions. The "uc" may safely be NULL.
extern PERFTOOLS_DLL_DECL int GetStackTraceWithContext(void** result, int max_depth,
int skip_count, const void *uc);
#endif /* GOOGLE_STACKTRACE_H_ */