/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   file Copyright.txt or https://cmake.org/licensing for details.  */
#pragma once
#include "cmConfigure.h"  // IWYU pragma: keep

#include "cm_uv.h"

#if defined(CMAKE_USE_SYSTEM_LIBUV) && !defined(_WIN32) &&                     \
    UV_VERSION_MAJOR == 1 && UV_VERSION_MINOR < 19
#    define CMAKE_UV_SIGNAL_HACK
#    include "cmUVHandlePtr.h"
/*
   libuv does not use SA_RESTART on its signal handler, but C++ streams
   depend on it for reliable i/o operations.  This RAII helper convinces
   libuv to install its handler, and then revises the handler to add the
   SA_RESTART flag.  We use a distinct uv loop that never runs to avoid
   ever really getting a callback.  libuv may fill the hack loop's signal
   pipe and then stop writing, but that won't break any real loops.
 */
class cmUVSignalHackRAII
{
    uv_loop_t         HackLoop;
    cm::uv_signal_ptr HackSignal;
    static void       HackCB(uv_signal_t*, int) {}

public:
    cmUVSignalHackRAII()
    {
        uv_loop_init(&this->HackLoop);
        this->HackSignal.init(this->HackLoop);
        this->HackSignal.start(HackCB, SIGCHLD);
        struct sigaction hack_sa;
        sigaction(SIGCHLD, nullptr, &hack_sa);
        if(!(hack_sa.sa_flags & SA_RESTART))
        {
            hack_sa.sa_flags |= SA_RESTART;
            sigaction(SIGCHLD, &hack_sa, nullptr);
        }
    }
    ~cmUVSignalHackRAII()
    {
        this->HackSignal.stop();
        uv_loop_close(&this->HackLoop);
    }
};
#endif
