// Copyright 2010 Google Inc.
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//
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// modification, are permitted provided that the following conditions are
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//
// * Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
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//   may be used to endorse or promote products derived from this software
//   without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include "utils/process/status.hpp"

extern "C" {
#include <sys/resource.h>
#include <sys/wait.h>

#include <signal.h>
#include <unistd.h>
}

#include <cstdlib>

#include <atf-c++.hpp>

using utils::process::status;


namespace {


/// Body of a subprocess that exits with a particular exit status.
///
/// \tparam ExitStatus The status to exit with.
template< int ExitStatus >
void child_exit(void)
{
    std::exit(ExitStatus);
}


/// Body of a subprocess that sends a particular signal to itself.
///
/// \tparam Signo The signal to send to self.
template< int Signo >
void child_signal(void)
{
    ::kill(::getpid(), Signo);
}


/// Spawns a process and waits for completion.
///
/// \param hook The function to run within the child.  Should not return.
///
/// \return The termination status of the spawned subprocess.
status
fork_and_wait(void (*hook)(void))
{
    pid_t pid = ::fork();
    ATF_REQUIRE(pid != -1);
    if (pid == 0) {
        hook();
        std::abort();
    } else {
        int stat_loc;
        ATF_REQUIRE(::waitpid(pid, &stat_loc, 0) != -1);
        const status s = status(pid, stat_loc);
        ATF_REQUIRE_EQ(pid, s.dead_pid());
        return s;
    }
}


}  // anonymous namespace


ATF_TEST_CASE_WITHOUT_HEAD(fake_exited)
ATF_TEST_CASE_BODY(fake_exited)
{
    const status fake = status::fake_exited(123);
    ATF_REQUIRE_EQ(-1, fake.dead_pid());
    ATF_REQUIRE(fake.exited());
    ATF_REQUIRE_EQ(123, fake.exitstatus());
    ATF_REQUIRE(!fake.signaled());
}


ATF_TEST_CASE_WITHOUT_HEAD(fake_signaled)
ATF_TEST_CASE_BODY(fake_signaled)
{
    const status fake = status::fake_signaled(567, true);
    ATF_REQUIRE_EQ(-1, fake.dead_pid());
    ATF_REQUIRE(!fake.exited());
    ATF_REQUIRE(fake.signaled());
    ATF_REQUIRE_EQ(567, fake.termsig());
    ATF_REQUIRE(fake.coredump());
}


ATF_TEST_CASE_WITHOUT_HEAD(integration__exited);
ATF_TEST_CASE_BODY(integration__exited)
{
    const status exit_success = fork_and_wait(child_exit< EXIT_SUCCESS >);
    ATF_REQUIRE(exit_success.exited());
    ATF_REQUIRE_EQ(EXIT_SUCCESS, exit_success.exitstatus());
    ATF_REQUIRE(!exit_success.signaled());

    const status exit_failure = fork_and_wait(child_exit< EXIT_FAILURE >);
    ATF_REQUIRE(exit_failure.exited());
    ATF_REQUIRE_EQ(EXIT_FAILURE, exit_failure.exitstatus());
    ATF_REQUIRE(!exit_failure.signaled());
}


ATF_TEST_CASE_WITHOUT_HEAD(integration__signaled);
ATF_TEST_CASE_BODY(integration__signaled)
{
    const status sigterm = fork_and_wait(child_signal< SIGTERM >);
    ATF_REQUIRE(!sigterm.exited());
    ATF_REQUIRE(sigterm.signaled());
    ATF_REQUIRE_EQ(SIGTERM, sigterm.termsig());
    ATF_REQUIRE(!sigterm.coredump());

    const status sigkill = fork_and_wait(child_signal< SIGKILL >);
    ATF_REQUIRE(!sigkill.exited());
    ATF_REQUIRE(sigkill.signaled());
    ATF_REQUIRE_EQ(SIGKILL, sigkill.termsig());
    ATF_REQUIRE(!sigkill.coredump());
}


ATF_TEST_CASE_WITHOUT_HEAD(integration__coredump);
ATF_TEST_CASE_BODY(integration__coredump)
{
    struct rlimit rl;
    rl.rlim_cur = RLIM_INFINITY;
    rl.rlim_max = RLIM_INFINITY;
    if (::setrlimit(RLIMIT_CORE, &rl) == -1)
        skip("Cannot unlimit the core file size; check limits manually");

    const status coredump = fork_and_wait(child_signal< SIGQUIT >);
    ATF_REQUIRE(!coredump.exited());
    ATF_REQUIRE(coredump.signaled());
    ATF_REQUIRE_EQ(SIGQUIT, coredump.termsig());
#if !defined(WCOREDUMP)
    expect_fail("Platform does not support checking for coredump");
#endif
    ATF_REQUIRE(coredump.coredump());
}


ATF_INIT_TEST_CASES(tcs)
{
    ATF_ADD_TEST_CASE(tcs, fake_exited);
    ATF_ADD_TEST_CASE(tcs, fake_signaled);

    ATF_ADD_TEST_CASE(tcs, integration__exited);
    ATF_ADD_TEST_CASE(tcs, integration__signaled);
    ATF_ADD_TEST_CASE(tcs, integration__coredump);
}