Java example source code file (jvm_windows.cpp)

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Java - Java tags/keywords

ill, int, jvm_end, jvm_entry_no_env, jvm_leaf, jvm_raisesignal, reducesignalusage, segv, shutdown1_signal, shutdown2_signal, sigabrt, sigbreak, sigfpe, sigint

The jvm_windows.cpp Java example source code

/*
 * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "prims/jvm.h"
#include "runtime/interfaceSupport.hpp"
#include "runtime/osThread.hpp"

#include <signal.h>

JVM_LEAF(void*, JVM_GetThreadInterruptEvent())
  return Thread::current()->osthread()->interrupt_event();
JVM_END

// sun.misc.Signal ///////////////////////////////////////////////////////////
// Signal code is mostly copied from classic vm, signals_md.c   1.4 98/08/23
/*
 * This function is included primarily as a debugging aid. If Java is
 * running in a console window, then pressing <CTRL-BREAK> will cause
 * the current state of all active threads and monitors to be written
 * to the console window.
 */

JVM_ENTRY_NO_ENV(void*, JVM_RegisterSignal(jint sig, void* handler))
  // Copied from classic vm
  // signals_md.c       1.4 98/08/23
  void* newHandler = handler == (void *)2
                   ? os::user_handler()
                   : handler;
  switch (sig) {
   case SIGFPE:
     return (void *)-1; /* already used by VM */
   case SIGBREAK:
     if (!ReduceSignalUsage) return (void *)-1;

    /* The following signals are used for Shutdown Hooks support. However, if
       ReduceSignalUsage (-Xrs) is set, Shutdown Hooks must be invoked via
       System.exit(), Java is not allowed to use these signals, and the the
       user is allowed to set his own _native_ handler for these signals and
       invoke System.exit() as needed. Terminator.setup() is avoiding
       registration of these signals when -Xrs is present. */
   case SHUTDOWN1_SIGNAL:
   case SHUTDOWN2_SIGNAL:
     if (ReduceSignalUsage) return (void*)-1;
  }

  void* oldHandler = os::signal(sig, newHandler);
  if (oldHandler == os::user_handler()) {
      return (void *)2;
  } else {
      return oldHandler;
  }
JVM_END


JVM_ENTRY_NO_ENV(jboolean, JVM_RaiseSignal(jint sig))
  if (ReduceSignalUsage) {
    // do not allow SHUTDOWN1_SIGNAL,SHUTDOWN2_SIGNAL,BREAK_SIGNAL
    // to be raised when ReduceSignalUsage is set, since no handler
    // for them is actually registered in JVM or via JVM_RegisterSignal.
    if (sig == SHUTDOWN1_SIGNAL || sig == SHUTDOWN2_SIGNAL ||
        sig == SIGBREAK) {
      return JNI_FALSE;
    }
  }
  os::signal_raise(sig);
  return JNI_TRUE;
JVM_END


/*
  All the defined signal names for Windows.

  NOTE that not all of these names are accepted by FindSignal!

  For various reasons some of these may be rejected at runtime.

  Here are the names currently accepted by a user of sun.misc.Signal with
  1.4.1 (ignoring potential interaction with use of chaining, etc):

     (LIST TBD)

*/
struct siglabel {
  char *name;
  int   number;
};

struct siglabel siglabels[] =
  /* derived from version 6.0 VC98/include/signal.h */
  {"ABRT",      SIGABRT,        /* abnormal termination triggered by abort cl */
  "FPE",        SIGFPE,         /* floating point exception */
  "SEGV",       SIGSEGV,        /* segment violation */
  "INT",        SIGINT,         /* interrupt */
  "TERM",       SIGTERM,        /* software term signal from kill */
  "BREAK",      SIGBREAK,       /* Ctrl-Break sequence */
  "ILL",        SIGILL};        /* illegal instruction */

JVM_ENTRY_NO_ENV(jint, JVM_FindSignal(const char *name))
  /* find and return the named signal's number */

  for(int i=0;i<sizeof(siglabels)/sizeof(struct siglabel);i++)
    if(!strcmp(name, siglabels[i].name))
      return siglabels[i].number;
  return -1;
JVM_END