Function BOOST_CATCH

include/boost/stacktrace/stacktrace.hpp:74–134

/// @tparam Allocator Allocator to use during stack capture.
template <class Allocator>
class basic_stacktrace {
    std::vector<boost::stacktrace::frame, Allocator> impl_;
    typedef boost::stacktrace::detail::native_frame_ptr_t native_frame_ptr_t;

    /// @cond
    void fill(native_frame_ptr_t* begin, std::size_t size) {
        if (!size) {
            return;
        }

        impl_.reserve(static_cast<std::size_t>(size));
        for (std::size_t i = 0; i < size; ++i) {
            if (!begin[i]) {
                return;
            }
            impl_.push_back(
                frame(begin[i])
            );
        }
    }

    static std::size_t frames_count_from_buffer_size(std::size_t buffer_size) noexcept {
        const std::size_t ret = (buffer_size > sizeof(native_frame_ptr_t) ? buffer_size / sizeof(native_frame_ptr_t) : 0);
        return (ret > 1024 ? 1024 : ret); // Dealing with suspiciously big sizes
    }

    BOOST_NOINLINE void init(std::size_t frames_to_skip, std::size_t max_depth) {
        constexpr std::size_t buffer_size = 128;
        if (!max_depth) {
            return;
        }

        BOOST_TRY {
            {   // Fast path without additional allocations
                native_frame_ptr_t buffer[buffer_size];
                const std::size_t frames_count = boost::stacktrace::detail::this_thread_frames::collect(buffer, buffer_size < max_depth ? buffer_size : max_depth, frames_to_skip + 1);
                if (buffer_size > frames_count || frames_count == max_depth) {
                    fill(buffer, frames_count);
                    return;
                }
            }

            // Failed to fit in `buffer_size`. Allocating memory:
#ifdef BOOST_NO_CXX11_ALLOCATOR
            typedef typename Allocator::template rebind<native_frame_ptr_t>::other allocator_void_t;
#else
            typedef typename std::allocator_traits<Allocator>::template rebind_alloc<native_frame_ptr_t> allocator_void_t;
#endif
            std::vector<native_frame_ptr_t, allocator_void_t> buf(buffer_size * 2, 0, impl_.get_allocator());
            do {
                const std::size_t frames_count = boost::stacktrace::detail::this_thread_frames::collect(&buf[0], buf.size() < max_depth ? buf.size() : max_depth, frames_to_skip + 1);
                if (buf.size() > frames_count || frames_count == max_depth) {
                    fill(&buf[0], frames_count);
                    return;
                }

                buf.resize(buf.size() * 2);
            } while (buf.size() < buf.max_size()); // close to `true`, but suppresses `C4127: conditional expression is constant`.