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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.datastax.oss.driver.internal.core.os;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/** A gateway to perform system calls. */
public class Native {
private static final Logger LOG = LoggerFactory.getLogger(Native.class);
private static class LibcLoader {
/* These values come from Graal's imageinfo API which aims to offer the ability to detect
* when we're in the Graal build/run time via system props. The maintainers of Graal have
* agreed that this API will not change over time. We reference these props as literals
* to avoid introducing a dependency on Graal code for non-Graal users here. */
private static final String GRAAL_STATUS_PROP = "org.graalvm.nativeimage.imagecode";
private static final String GRAAL_BUILDTIME_STATUS = "buildtime";
private static final String GRAAL_RUNTIME_STATUS = "runtime";
public Libc load() {
try {
if (isGraal()) {
LOG.info("Using Graal-specific native functions");
return new GraalLibc();
}
return new JnrLibc();
} catch (Throwable t) {
LOG.info(
"Unable to load JNR native implementation. This could be normal if JNR is excluded from the classpath",
t);
return new EmptyLibc();
}
}
private boolean isGraal() {
String val = System.getProperty(GRAAL_STATUS_PROP);
return val != null
&& (val.equals(GRAAL_RUNTIME_STATUS) || val.equalsIgnoreCase(GRAAL_BUILDTIME_STATUS));
}
}
private static final Libc LIBC = new LibcLoader().load();
private static final CpuInfo.Cpu CPU = CpuInfo.determineCpu();
private static final String NATIVE_CALL_ERR_MSG = "Native call failed or was not available";
/** Whether {@link Native#currentTimeMicros()} is available on this system. */
public static boolean isCurrentTimeMicrosAvailable() {
return LIBC.available();
}
/**
* The current time in microseconds, as returned by libc.gettimeofday(); can only be used if
* {@link #isCurrentTimeMicrosAvailable()} is true.
*/
public static long currentTimeMicros() {
return LIBC.gettimeofday().orElseThrow(() -> new IllegalStateException(NATIVE_CALL_ERR_MSG));
}
public static boolean isGetProcessIdAvailable() {
return LIBC.available();
}
public static int getProcessId() {
return LIBC.getpid().orElseThrow(() -> new IllegalStateException(NATIVE_CALL_ERR_MSG));
}
/**
* Returns the current processor architecture the JVM is running on. This value should match up to
* what's returned by jnr-ffi's Platform.getCPU() method.
*
* @return the current processor architecture.
*/
public static String getCpu() {
return CPU.toString();
}
}