/*
* Copyright 2017-2018 Uber Technologies, Inc.
*
* 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 com.uber.h3core;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
/**
* Extracts the native H3 core library to the local filesystem and loads it.
*/
public final class H3CoreLoader {
private H3CoreLoader() {
// Prevent instantiation
}
// Supported H3 architectures
static final String ARCH_X64 = "x64";
static final String ARCH_X86 = "x86";
static final String ARCH_ARM64 = "arm64";
private static volatile File libraryFile = null;
/**
* Read all bytes from <code>in</code> and write them to <code>out</code>.
*/
private static void copyStream(InputStream in, OutputStream out) throws IOException {
byte[] buf = new byte[4096];
int read;
while ((read = in.read(buf)) != -1) {
out.write(buf, 0, read);
}
}
/**
* Copy the resource at the given path to the file. File will be made readable,
* writable, and executable.
*
* @param resourcePath Resource to copy
* @param newH3LibFile File to write
* @throws UnsatisfiedLinkError The resource path does not exist
*/
static void copyResource(String resourcePath, File newH3LibFile) throws IOException {
// Set the permissions
newH3LibFile.setReadable(true);
newH3LibFile.setWritable(true, true);
newH3LibFile.setExecutable(true, true);
// Shove the resource into the file and close it
try (InputStream resource = H3CoreLoader.class.getResourceAsStream(resourcePath)) {
if (resource == null) {
throw new UnsatisfiedLinkError(String.format("No native resource found at %s", resourcePath));
}
try (FileOutputStream outFile = new FileOutputStream(newH3LibFile)) {
copyStream(resource, outFile);
}
}
}
/**
* For use when the H3 library should be unpacked from the JAR and loaded.
*
* @throws SecurityException Loading the library was not allowed by the
* SecurityManager.
* @throws UnsatisfiedLinkError The library could not be loaded
* @throws IOException Failed to unpack the library
*/
public static NativeMethods loadNatives() throws IOException {
final OperatingSystem os = detectOs(System.getProperty("java.vendor"), System.getProperty("os.name"));
final String arch = detectArch(System.getProperty("os.arch"));
return loadNatives(os, arch);
}
/**
* For use when the H3 library should be unpacked from the JAR and loaded.
* The native library for the specified operating system and architecture
* will be extract.
*
* <p>H3 will only successfully extract the library once, even if different
* operating system and architecture are specified, or if {@link #loadNatives()}
* was used instead.
*
* @throws SecurityException Loading the library was not allowed by the
* SecurityManager.
* @throws UnsatisfiedLinkError The library could not be loaded
* @throws IOException Failed to unpack the library
* @param os Operating system whose lobrary should be used
* @param arch Architecture name, as packaged in the H3 library
*/
public synchronized static NativeMethods loadNatives(OperatingSystem os, String arch) throws IOException {
// This is synchronized because if multiple threads were writing and
// loading the shared object at the same time, bad things could happen.
if (libraryFile == null) {
final String dirName = String.format("%s-%s", os.getDirName(), arch);
final String libName = String.format("libh3-java%s", os.getSuffix());
final File newLibraryFile = File.createTempFile("libh3-java", os.getSuffix());
newLibraryFile.deleteOnExit();
copyResource(String.format("/%s/%s", dirName, libName), newLibraryFile);
System.load(newLibraryFile.getCanonicalPath());
libraryFile = newLibraryFile;
}
return new NativeMethods();
}
/**
* For use when the H3 library is installed system-wide and Java is able to locate it.
*
* @throws SecurityException Loading the library was not allowed by the
* SecurityManager.
* @throws UnsatisfiedLinkError The library could not be loaded
*/
public static NativeMethods loadSystemNatives() {
System.loadLibrary("h3-java");
return new NativeMethods();
}
/**
* Operating systems supported by H3-Java.
*/
public enum OperatingSystem {
ANDROID(".so"),
DARWIN(".dylib"),
WINDOWS(".dll"),
LINUX(".so");
private final String suffix;
OperatingSystem(String suffix) {
this.suffix = suffix;
}
/**
* Suffix for native libraries.
*/
public String getSuffix() {
return suffix;
}
/**
* How this operating system's name is rendered when extracting the native library.
*/
public String getDirName() {
return name().toLowerCase();
}
}
/**
* Detect the current operating system.
*
* @param javaVendor Value of system property "java.vendor"
* @param osName Value of system property "os.name"
*/
static final OperatingSystem detectOs(String javaVendor, String osName) {
// Detecting Android using the properties from:
// https://developer.android.com/reference/java/lang/System.html
if (javaVendor.toLowerCase().contains("android")) {
return OperatingSystem.ANDROID;
}
String javaOs = osName.toLowerCase();
if (javaOs.contains("mac")) {
return OperatingSystem.DARWIN;
} else if (javaOs.contains("win")) {
return OperatingSystem.WINDOWS;
} else {
// Only other supported platform
return OperatingSystem.LINUX;
}
}
/**
* Detect the system architecture.
*
* @param osArch Value of system property "os.arch"
*/
static final String detectArch(String osArch) {
if (osArch.equals("amd64") || osArch.equals("x86_64")) {
return ARCH_X64;
} else if (osArch.equals("i386") ||
osArch.equals("i486") ||
osArch.equals("i586") ||
osArch.equals("i686") ||
osArch.equals("i786") ||
osArch.equals("i886")) {
return ARCH_X86;
} else if (osArch.equals("aarch64")) {
return ARCH_ARM64;
} else {
return osArch;
}
}
}
