Ticket #18549: test-signal.cpp

/*
    Signals test program.
    
    This program spawns a subprocess which will use abort() to end. It is
    expected that this parent will then be able to capture that signal as part
    of why it is killed.
*/

#include <cstdlib>
#include <iostream>

#include <signal.h>
#include <spawn.h>
#include <sys/wait.h>


int
main(int argc, char** argv)
{
    // Check if we are the child process; this is the case we have arguments.
    if (argc > 1)
        std::abort();

    // Main process: set up a child process and capture on which signal it terminated
    pid_t childPid;
    char* childArgv[] = {argv[0], "abort", nullptr};
    if (auto status = posix_spawn(&childPid, argv[0], nullptr, nullptr, childArgv, nullptr);
            status != 0)
    {
        std::cerr << "Error spawning process: " << strerror(status) << std::endl;
        return status;
    }

    int childStatus;
    auto returnPid = waitpid(childPid, &childStatus, 0);
    if (returnPid != childPid) {
        std::cerr << "waitpid() did not return the requested pid" << std::endl;
        return -1;
    }
    if (!WIFSIGNALED(childStatus) != 0) {
        std::cerr << "waidpid(): the child process was expected to stop due to an uncaught signal"
            << std::endl;
        return -1;
    }
    if (auto signal = WTERMSIG(childStatus); signal != SIGABRT) {
        std::cerr << "the child process ended with signal " << signal << " instead of SIGABRT"
            << std::endl;
        return -1;
    }
    
    std::cout << "Test succeeded: child signal SIGABRT was transmitted correctly" << std::endl;
    return 0;
}