X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/73964e0702f4c60d487bad44f6be8fd472680485..ac080087b39ef79ff497d3992ff04b3e20fe40b2:/src/bindings/java/org/simgrid/NativeLib.java

diff --git a/src/bindings/java/org/simgrid/NativeLib.java b/src/bindings/java/org/simgrid/NativeLib.java
index 130c904f6c..a338cc3e93 100644
--- a/src/bindings/java/org/simgrid/NativeLib.java
+++ b/src/bindings/java/org/simgrid/NativeLib.java
@@ -1,112 +1,176 @@
+/* Copyright (c) 2014-2019. The SimGrid Team. All rights reserved.          */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
 package org.simgrid;
 
 import java.io.FileOutputStream;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.OutputStream;
 import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.stream.Stream;
 
+/** Helper class loading the native functions of SimGrid that we use for downcalls
+ *
+ * Almost all org.simgrid.msg.* classes contain a static bloc (thus executed when the class is loaded)
+ * containing a call to this.
+ */
 public final class NativeLib {
+	private static boolean isNativeInited = false;
+	private static Path tempDir = null; // where the embeeded libraries are unpacked before loading them
 
-    public static String getPath() {
-        String prefix = "NATIVE";
-        String os = System.getProperty("os.name");
-        String arch = System.getProperty("os.arch");
-
-        if (os.toLowerCase().startsWith("^win"))
-            os = "Windows";
-        else if (os.contains("OS X"))
-            os = "Darwin";
-
-        if (arch.matches("^i[3-6]86$"))
-            arch = "x86";
-        else if (arch.equalsIgnoreCase("amd64"))
-            arch = "x86_64";
-
-        os = os.replace(' ', '_');
-        arch = arch.replace(' ', '_');
-
-        return prefix + "/" + os + "/" + arch + "/";
-    }
-    public static void nativeInit(String name) {
-        try {
-            /* prefer the version on disk, if existing */
-            System.loadLibrary(name);
-        } catch (UnsatisfiedLinkError e) {
-            /* If not found, unpack the one bundled into the jar file and use it */
-            loadLib(name);
-        }
-    }
-
-    private static void loadLib (String name) {
-        String Path = NativeLib.getPath();
-
-        String filename=name;
-        InputStream in = NativeLib.class.getClassLoader().getResourceAsStream(Path+filename);
-		
-        if (in == null) {
-	    filename = "lib"+name+".so";
-            in = NativeLib.class.getClassLoader().getResourceAsStream(Path+filename);
-        } 
-	if (in == null) {
-	    filename = name+".dll";
-	    in =  NativeLib.class.getClassLoader().getResourceAsStream(Path+filename);
-	}  
-	if (in == null) {
-	    filename = "lib"+name+".dll";
-	    in =  NativeLib.class.getClassLoader().getResourceAsStream(Path+filename);
-	}  
-	if (in == null) {
-	    filename = "lib"+name+".dylib";
-	    in =  NativeLib.class.getClassLoader().getResourceAsStream(Path+filename);
-	}  
-	if (in == null) {
-	    throw new RuntimeException("Cannot find library "+name+" in path "+Path+". Sorry, but this jar does not seem to be usable on your machine.");
+	/** A static-only "class" don't need no constructor */
+	private NativeLib() {
+		throw new IllegalAccessError("Utility class");
+	}
+
+	/** Hidden debug main() function
+	 *
+	 * It is not the Main-Class defined in src/bindings/java/MANIFEST.in (org.simgrid.msg.Msg is),
+	 * so it won't get executed by default. But that's helpful to debug linkage errors, if you
+	 * know that it exists. It's used by cmake during the configure, to inform the user.
+	 */
+	public static void main(String[] args) {
+		System.out.println("This jarfile searches the native code under: " +getPath());
 	}
-	try {
-	    // We must write the lib onto the disk before loading it -- stupid operating systems
-	    File fileOut = new File(filename);
-	    fileOut = File.createTempFile(name+"-", ".tmp");
-	    // don't leak the file on disk, but remove it on JVM shutdown
-	    Runtime.getRuntime().addShutdownHook(new Thread(new FileCleaner(fileOut.getAbsolutePath())));
-	    OutputStream out = new FileOutputStream(fileOut);
-			
-	    /* copy the library in position */  
-	    byte[] buffer = new byte[4096]; 
-	    int bytes_read; 
-	    while ((bytes_read = in.read(buffer)) != -1)     // Read until EOF
-		    out.write(buffer, 0, bytes_read); 
-		      
-	    /* close all file descriptors, and load that shit */
-	    in.close();
-	    out.close();
-	    System.load(fileOut.getAbsolutePath());
-
-	} catch (Exception e) {
-	    System.err.println("Cannot load the bindings to the "+name+" library: ");
-	    e.printStackTrace();
-	    System.err.println("This jar file does not seem to fit your system, sorry");
-	    System.exit(1);
+	
+	/** Main function loading all the native classes that we need */
+	public static void nativeInit() {
+		if (isNativeInited)
+			return;
+
+		if (System.getProperty("os.name").toLowerCase().startsWith("win"))
+			NativeLib.nativeInit("winpthread-1");
+
+		NativeLib.nativeInit("simgrid");
+		NativeLib.nativeInit("simgrid-java");
+		isNativeInited = true;
 	}
-    }
-    
-	/* A hackish mechanism used to remove the file containing our library when the JVM shuts down */
-	private static class FileCleaner implements Runnable {
-		private String target;
-		public FileCleaner(String name) {
-			target = name;
+
+	/** Helper function trying to load one requested library */
+	public static void nativeInit(String name) {
+		Throwable cause = null;
+		try {
+			/* Prefer the version of the library bundled into the jar file and use it */
+			if (loadLibAsStream(name))
+				return;
+		} catch (UnsatisfiedLinkError|SecurityException|IOException e) {
+			cause = e;
 		}
-        public void run() {
-            try {
-                new File(target).delete();
-            } catch(Exception e) {
-                System.out.println("Unable to clean temporary file "+target+" during shutdown.");
-                e.printStackTrace();
-            }
-        }    
+		
+		/* If not found, try to see if we can find a version on disk */
+		try {
+			System.loadLibrary(name);
+			return;
+		} catch (UnsatisfiedLinkError systemException) { /* don't care */ }
+		
+		System.err.println("\nCannot load the bindings to the "+name+" library in path "+getPath()+" and no usable SimGrid installation found on disk.");
+		if (cause != null) {
+			if (cause.getMessage().contains("libcgraph.so"))
+				System.err.println("HINT: Try to install the libcgraph package (sudo apt-get install libcgraph).");
+			else if (cause.getMessage().contains("libboost_context.so"))
+				System.err.println("HINT: Try to install the boost-context package (sudo apt-get install libboost-context-dev).");
+			else
+				System.err.println("Try to install the missing dependencies, if any. Read carefully the following error message.");
+
+			System.err.println();
+			cause.printStackTrace();
+		} else {
+			System.err.println("This jar file does not seem to fit your system, and no usable SimGrid installation found on disk for "+name+".");
+		}
+		System.exit(1);
 	}
 
+	/** Try to extract the library from the jarfile before loading it */
+	private static boolean loadLibAsStream (String name) throws IOException, UnsatisfiedLinkError {
+		String path = NativeLib.getPath();
+		
+		// We must write the lib onto the disk before loading it -- stupid operating systems
+		if (tempDir == null) {
+			tempDir = Files.createTempDirectory("simgrid-java-");
+			// don't leak the files on disk, but remove it on JVM shutdown
+			Runtime.getRuntime().addShutdownHook(new Thread(new FileCleaner(tempDir.toFile())));
+		}
+		
+		/* For each possible filename of the given library on all possible OSes, try it */
+		for (String filename : new String[]
+		   { name,
+		     "lib"+name+".so",               /* linux */
+		     name+".dll", "lib"+name+".dll", /* windows (pure and mingw) */
+		     "lib"+name+".dylib"             /* macOS */}) {
+						
+			File fileOut = new File(tempDir.toFile().getAbsolutePath() + File.separator + filename);
+			boolean done = false;
+			try ( // Try-with-resources. These stream will be autoclosed when needed.
+				InputStream in = NativeLib.class.getClassLoader().getResourceAsStream(path+filename);
+				OutputStream out = new FileOutputStream(fileOut);
+			) {
+				if (in != null) {
+					/* copy the library in position */
+					byte[] buffer = new byte[4096];
+					int bytesRead;
+					while ((bytesRead = in.read(buffer)) != -1)     // Read until EOF
+						out.write(buffer, 0, bytesRead);
+					done = true;
+				}
+			}
+			if (done) {
+				/* load that library */
+				System.load(fileOut.getAbsolutePath());
+
+				/* It loaded! we're good */
+				return true;
+			}
+		}
+		
+		/* No suitable name found */
+		return false;
+	}
+
+	/** Find where to search for the library in the jar -- keep it aligned with where cmake puts it! */
+	private static String getPath() {
+		// Inspiration: https://github.com/xerial/snappy-java/blob/develop/src/main/java/org/xerial/snappy/OSInfo.java
+		String prefix = "NATIVE";
+		String os = System.getProperty("os.name");
+		String arch = System.getProperty("os.arch");
+
+		if (arch.matches("^i[3-6]86$"))
+			arch = "x86";
+		else if ("x86_64".equalsIgnoreCase(arch) || "AMD64".equalsIgnoreCase(arch))
+			arch = "amd64";
 
-    public static void main(String[] args) {
-        System.out.println(getPath());
-    }
+		if (os.toLowerCase().startsWith("win")) {
+			os = "Windows";
+		} else if (os.contains("OS X")) {
+			os = "Darwin";
+		}
+		os = os.replace(' ', '_');
+		arch = arch.replace(' ', '_');
+
+		return prefix + "/" + os + "/" + arch + "/";
+	}
+	
+	/** A hackish mechanism used to remove the file containing our library when the JVM shuts down */
+	private static class FileCleaner implements Runnable {
+		private File dir;
+		public FileCleaner(File dir) {
+			this.dir = dir;
+		}
+		@Override
+		public void run() {
+                        try (Stream<Path> paths = Files.walk(dir.toPath())) {
+                                paths.sorted(java.util.Comparator.reverseOrder())
+                                     .map(java.nio.file.Path::toFile)
+                                     //.peek(System.out::println) // Prints what gets removed
+                                     .forEach(java.io.File::delete);
+			} catch(Exception e) {
+				System.out.println("Error while cleaning temporary file "+dir.getAbsolutePath()+" during shutdown: "+e.getCause());
+				e.printStackTrace();
+                        }
+		}
+	}
 }