test/hotspot/gtest/runtime/test_signals.cpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "precompiled.hpp"
#ifndef _WIN32
#include "runtime/os.hpp"
#include "utilities/ostream.hpp"
#include "unittest.hpp"

#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <sys/ucontext.h>
#include <string.h>

extern "C" {
  static void sig_handler(int sig) {
    printf( " HANDLER (1) " );
  }
}

class PosixSignalTest : public ::testing::Test {
  public:

  static void check_handlers() {
    struct sigaction act, old_SIGFPE_act, old_SIGILL_act;
    act.sa_handler = sig_handler;
    sigemptyset(&act.sa_mask);
    act.sa_flags = 0;
    ASSERT_NE(sigaction(SIGFPE, &act, &old_SIGFPE_act), -1) << "Setting SIGFPE handler failed: " << os::strerror(errno) << " (" << errno << ")";
    ASSERT_NE(sigaction(SIGILL, &act, &old_SIGILL_act), -1) << "Setting SIGILL handler failed: " <<  os::strerror(errno) << " (" << errno << ")";

    // Use local stringStream to capture output from run_periodic_checks() calls to
    // print_signal_handlers().
    stringStream st;
    os::run_periodic_checks(&st);
    char* res = (char *)st.base(); // res can't be const because some strstr()'s have non-const first args.

    // Restore signal handlers.
    ASSERT_NE(sigaction(SIGFPE, &act, &old_SIGFPE_act), -1) << "Restoring SIGFPE handler failed: " << os::strerror(errno) << " (" << errno << ")";
    ASSERT_NE(sigaction(SIGILL, &act, &old_SIGILL_act), -1) << "Restoring SIGILL handler failed: " << os::strerror(errno) << " (" << errno << ")";

    // Check that "Handler was modified" occurs exactly twice in the tty output.
    char* modified = strstr(res, "Handler was modified!");
    ASSERT_NE(modified, nullptr) << "No message found";

    modified = strstr(modified + 1, "Handler was modified!");
    ASSERT_NE(modified, nullptr) << "Only one message found";
    ASSERT_EQ(strstr(modified + 1, "Handler was modified!"), nullptr) << "Too many messages found";
  }
};

// This tests the fix for JDK-8285792.
TEST_OTHER_VM(PosixSignalTest, check_handlers) {
  PosixSignalTest::check_handlers();
}

#endif