vmruntime.c

来自「linux下建立JAVA虚拟机的源码KAFFE」· C语言 代码 · 共 103 行

/* src/native/vm/VMRuntime.c - java/lang/VMRuntime

   Copyright (C) 1996-2005 R. Grafl, A. Krall, C. Kruegel, C. Oates,
   R. Obermaisser, M. Platter, M. Probst, S. Ring, E. Steiner,
   C. Thalinger, D. Thuernbeck, P. Tomsich, C. Ullrich, J. Wenninger,
   Institut f. Computersprachen - TU Wien

   Copyright (C) 2005 Dalibor Topic

   This file was taken from CACAO. More information on CACAO project
   is available at http://www.cacaojvm.org

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   This program 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 for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.

   Contact: [e-mail]

   Authors: Roman Obermaiser

   Changes: Joseph Wenninger
            Christian Thalinger
            Dalibor Topic
*/

#include "config.h"

#include <stdlib.h>

#if defined(HAVE_UNISTD_H)
#include <unistd.h>
#endif

#if defined(HAVE_SYS_SYSINFO_H)
#include <sys/sysinfo.h>
#endif

#if defined(HAVE_MACH_MACH_H)
# include <mach/mach.h>
#endif

#include "jni.h"

/*
 * Class:     java_lang_Runtime
 * Method:    availableProcessors
 * Signature: ()I
 */
JNIEXPORT jint JNICALL
Java_java_lang_VMRuntime_availableProcessors(JNIEnv *env UNUSED,
					     jclass clazz UNUSED)
{
#if defined(HAVE_GET_NPROCS_CONF)
	return get_nprocs_conf();
#elif defined(_SC_NPROC_ONLN)
	return (jint) sysconf(_SC_NPROC_ONLN);

#elif defined(_SC_NPROCESSORS_ONLN)
	return (jint) sysconf(_SC_NPROCESSORS_ONLN);

#elif defined(__DARWIN__)
	/* this should work in BSD */
	/*
	int ncpu, mib[2], rc;
	size_t len;

	mib[0] = CTL_HW;
	mib[1] = HW_NCPU;
	len = sizeof(ncpu);
	rc = sysctl(mib, 2, &ncpu, &len, NULL, 0);

	return (jint) ncpu;
	*/

	host_basic_info_data_t hinfo;
	mach_msg_type_number_t hinfo_count = HOST_BASIC_INFO_COUNT;
	kern_return_t rc;

	rc = host_info(mach_host_self(), HOST_BASIC_INFO,
				   (host_info_t) &hinfo, &hinfo_count);
 
	if (rc != KERN_SUCCESS) {
		return -1;
	}

    return (jint) hinfo.avail_cpus;

#else
	return 1;
#endif
}