boost/stacktrace/detail/libbacktrace_impls.hpp
// Copyright Antony Polukhin, 2016-2017.
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_STACKTRACE_DETAIL_LIBBACKTRACE_IMPLS_HPP
#define BOOST_STACKTRACE_DETAIL_LIBBACKTRACE_IMPLS_HPP
#include <boost/config.hpp>
#ifdef BOOST_HAS_PRAGMA_ONCE
# pragma once
#endif
#include <boost/stacktrace/detail/to_hex_array.hpp>
#include <boost/core/demangle.hpp>
#include <boost/lexical_cast.hpp>
#include <backtrace.h>
namespace boost { namespace stacktrace { namespace detail {
struct pc_data {
std::string* function;
std::string* filename;
std::size_t line;
};
inline int libbacktrace_full_callback(void *data, uintptr_t /*pc*/, const char *filename, int lineno, const char *function) {
pc_data& d = *static_cast<pc_data*>(data);
if (d.filename && filename) {
*d.filename = filename;
}
if (d.function && function) {
*d.function = function;
}
d.line = lineno;
return 0;
}
inline void libbacktrace_error_callback(void* /*data*/, const char* /*msg*/, int /*errnum*/) BOOST_NOEXCEPT {
// Do nothing, just return.
}
extern inline ::backtrace_state* construct_state() BOOST_NOEXCEPT {
return ::backtrace_create_state(
0, 0 /*thread-safe*/, boost::stacktrace::detail::libbacktrace_error_callback, 0
);
// TODO: this does not seem to work well when this function is in .so:
// Not async-signal-safe, so this method is not called from async-safe functions.
//
// This function is not async signal safe because:
// * Dynamic initialization of a block-scope variable with static storage duration could lock a mutex
// * No guarantees on `backtrace_create_state` function.
// [dcl.inline]: A static local variable in an inline function with external linkage always refers to the same object.
/*
static ::backtrace_state* state = ::backtrace_create_state(
0, 1 , boost::stacktrace::detail::libbacktrace_error_callback, 0
);
return state;
*/
}
struct to_string_using_backtrace {
std::string res;
::backtrace_state* state;
std::string filename;
std::size_t line;
void prepare_function_name(const void* addr) {
boost::stacktrace::detail::pc_data data = {&res, &filename, 0};
if (state) {
::backtrace_pcinfo(
state,
reinterpret_cast<uintptr_t>(addr),
boost::stacktrace::detail::libbacktrace_full_callback,
boost::stacktrace::detail::libbacktrace_error_callback,
&data
);
}
line = data.line;
}
bool prepare_source_location(const void* /*addr*/) {
if (filename.empty() || !line) {
return false;
}
res += " at ";
res += filename;
res += ':';
res += boost::lexical_cast<boost::array<char, 40> >(line).data();
return true;
}
to_string_using_backtrace() BOOST_NOEXCEPT {
state = boost::stacktrace::detail::construct_state();
}
};
template <class Base> class to_string_impl_base;
typedef to_string_impl_base<to_string_using_backtrace> to_string_impl;
inline std::string name_impl(const void* addr) {
std::string res;
::backtrace_state* state = boost::stacktrace::detail::construct_state();
boost::stacktrace::detail::pc_data data = {&res, 0, 0};
if (state) {
::backtrace_pcinfo(
state,
reinterpret_cast<uintptr_t>(addr),
boost::stacktrace::detail::libbacktrace_full_callback,
boost::stacktrace::detail::libbacktrace_error_callback,
&data
);
}
if (!res.empty()) {
res = boost::core::demangle(res.c_str());
}
return res;
}
} // namespace detail
std::string frame::source_file() const {
std::string res;
::backtrace_state* state = boost::stacktrace::detail::construct_state();
boost::stacktrace::detail::pc_data data = {0, &res, 0};
if (state) {
::backtrace_pcinfo(
state,
reinterpret_cast<uintptr_t>(addr_),
boost::stacktrace::detail::libbacktrace_full_callback,
boost::stacktrace::detail::libbacktrace_error_callback,
&data
);
}
return res;
}
std::size_t frame::source_line() const {
::backtrace_state* state = boost::stacktrace::detail::construct_state();
boost::stacktrace::detail::pc_data data = {0, 0, 0};
if (state) {
::backtrace_pcinfo(
state,
reinterpret_cast<uintptr_t>(addr_),
boost::stacktrace::detail::libbacktrace_full_callback,
boost::stacktrace::detail::libbacktrace_error_callback,
&data
);
}
return data.line;
}
}} // namespace boost::stacktrace
#endif // BOOST_STACKTRACE_DETAIL_LIBBACKTRACE_IMPLS_HPP