#ifndef V8_BASE_DEBUG_STACK_TRACE_H_

#define V8_BASE_DEBUG_STACK_TRACE_H_

#include <stddef.h>

#include <iosfwd>

#include <string>

#include "src/base/base-export.h"

#include "src/base/build_config.h"

#if V8_OS_POSIX

#include <unistd.h>

#endif

#if V8_OS_WIN

struct _EXCEPTION_POINTERS;

struct _CONTEXT;

#endif

namespace v8 {

namespace base {

namespace debug {

V8_BASE_EXPORT bool EnableInProcessStackDumping();

V8_BASE_EXPORT void DisableSignalStackDump();

class V8_BASE_EXPORT StackTrace {

public:

// Creates a stacktrace from the current location.

StackTrace();

// Creates a stacktrace from an existing array of instruction

// pointers (such as returned by Addresses()). |count| will be

// trimmed to |kMaxTraces|.

StackTrace(const void* const* trace, size_t count);

#if V8_OS_WIN

// Creates a stacktrace for an exception.

// Note: this function will throw an import not found (StackWalk64) exception

// on system without dbghelp 5.1.

explicit StackTrace(_EXCEPTION_POINTERS* exception_pointers);

explicit StackTrace(const _CONTEXT* context);

#endif

// Copying and assignment are allowed with the default functions.

~StackTrace();

// Gets an array of instruction pointer values. |*count| will be set to the

// number of elements in the returned array.

const void* const* Addresses(size_t* count) const;

// Prints the stack trace to stderr.

void Print() const;

// Resolves backtrace to symbols and write to stream.

void OutputToStream(std::ostream* os) const;

// Resolves backtrace to symbols and returns as string.

std::string ToString() const;

private:

#if V8_OS_WIN

void InitTrace(const _CONTEXT* context_record);

#endif

// From http://msdn.microsoft.com/en-us/library/bb204633.aspx,

// the sum of FramesToSkip and FramesToCapture must be less than 63,

// so set it to 62. Even if on POSIX it could be a larger value, it usually

// doesn't give much more information.

static const int kMaxTraces = 62;

void* trace_[kMaxTraces];

// The number of valid frames in |trace_|.

size_t count_;

};

} // namespace debug

} // namespace base

} // namespace v8

#endif // V8_BASE_DEBUG_STACK_TRACE_H_