io.questdb.jar.jni.JarJniLoader Maven / Gradle / Ivy
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/*******************************************************************************
* ___ _ ____ ____
* / _ \ _ _ ___ ___| |_| _ \| __ )
* | | | | | | |/ _ \/ __| __| | | | _ \
* | |_| | |_| | __/\__ \ |_| |_| | |_) |
* \__\_\\__,_|\___||___/\__|____/|____/
*
* Copyright (c) 2014-2019 Appsicle
* Copyright (c) 2019-2023 QuestDB
*
* Licensed 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 io.questdb.jar.jni;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
/**
* Loads native libraries from JAR files.
*/
public interface JarJniLoader {
/**
* Loads a native library from a JAR file.
*
* @param cls The class to use for loading the library.
* @param jarPathPrefix The path prefix to the library in the JAR file.
* @param name The name of the library, sans "lib" prefix and ".so|.dll|.dylib" suffix.
* @param platformDir The platform-specific subdirectory (inside jarPathPrefix) to load the library from,
* or null to search for the dynamic library directly within jarPathPrefix.
*/
static void loadLib(Class cls, String jarPathPrefix, String name, String platformDir) {
final String sep = jarPathPrefix.endsWith("/") ? "" : "/";
String pathInJar = jarPathPrefix + sep;
if (platformDir != null) {
pathInJar += platformDir + "/";
}
pathInJar += PlatformConventions.LIB_PREFIX + name + PlatformConventions.LIB_SUFFIX;
final InputStream is = cls.getResourceAsStream(pathInJar);
if (is == null) {
throw new LoadException("Internal error: cannot find " + pathInJar + ", broken package?");
}
try {
File tempLib = null;
try {
final int dot = pathInJar.indexOf('.');
tempLib = File.createTempFile(pathInJar.substring(0, dot), pathInJar.substring(dot));
// copy to tempLib
try (FileOutputStream out = new FileOutputStream(tempLib)) {
StreamTransfer.copyToStream(is, out);
} finally {
tempLib.deleteOnExit();
}
System.load(tempLib.getAbsolutePath());
} catch (IOException e) {
throw new LoadException("Internal error: cannot unpack " + tempLib, e);
}
} finally {
try {
is.close();
} catch (IOException e) {
// ignore
}
}
}
/**
* Loads a native library from a JAR file.
*
* The library is loaded from the platform-specific subdirectory of the jarPathPrefix.
*
* The platform-specific subdirectory derived from the current platform and
* the architecture of the JVM as determined by {@link Platform#RESOURCE_PREFIX}.
*
* For example if executing, JarJniLoader.loadLib(MyClass.class, "/native", "mylib");
* on a 64-bit x86 Linux system, the library will be loaded from "/native/linux-amd64/libmylib.so"
* from the same JAR file that contains MyClass.class.
* If executing on an Apple Silicon Macbook, the library will be loaded from
* "/native/mac_os_x-arm64/libmylib.dylib".
* From Windows 11, the library will be loaded from "/native/windows-amd64/mylib.dll" (note, no "lib" prefix).
*
* @param cls The class to use for loading the library.
* @param jarPathPrefix The path prefix to the library in the JAR file.
* @param name The name of the library, sans "lib" prefix and ".so|.dll|.dylib" suffix.
*/
static void loadLib(Class cls, String jarPathPrefix, String name) {
loadLib(cls, jarPathPrefix, name, Platform.RESOURCE_PREFIX);
}
}