Logo AND Algorithmique Numérique Distribuée

Public GIT Repository
7929fc7dbf76857490c5710fc11453d133ae6c7b
[simgrid.git] / src / bindings / java / org / simgrid / NativeLib.java
1 /* Copyright (c) 2014-2016. The SimGrid Team. All rights reserved.          */
2
3 /* This program is free software; you can redistribute it and/or modify it
4  * under the terms of the license (GNU LGPL) which comes with this package. */
5
6 package org.simgrid;
7
8 import java.io.FileOutputStream;
9 import java.io.InputStream;
10 import java.io.IOException;
11 import java.io.OutputStream;
12 import java.io.File;
13 import java.nio.file.Files;
14 import java.nio.file.Path;
15
16 /** Helper class loading the native functions of SimGrid that we use for downcalls 
17  * 
18  * Almost all org.simgrid.msg.* classes contain a static bloc (thus executed when the class is loaded) 
19  * containing a call to this.
20  */
21 public final class NativeLib {
22         private static boolean isNativeInited = false;
23         static Path tempDir = null; // where the embeeded libraries are unpacked before loading them
24
25         /** A static-only "class" don't need no constructor */
26         private NativeLib() {
27                 throw new IllegalAccessError("Utility class");
28         }
29
30         /** Hidden debug main() function 
31          * 
32          * It is not the Main-Class defined in src/bindings/java/MANIFEST.in (org.simgrid.msg.Msg is),
33          * so it won't get executed by default. But that's helpful to debug linkage errors, if you
34          * know that it exists. It's used by cmake during the configure, to inform the user.
35          */
36         public static void main(String[] args) {
37                 System.out.println("This jarfile searches the native code under: " +getPath());
38         }
39         
40         /** Main function loading all the native classes that we need */
41         public static void nativeInit() {
42                 if (isNativeInited)
43                         return;
44
45                 if (System.getProperty("os.name").toLowerCase().startsWith("win"))
46                         NativeLib.nativeInit("winpthread-1");
47
48                 NativeLib.nativeInit("simgrid");
49                 NativeLib.nativeInit("simgrid-java");
50                 isNativeInited = true;
51         }
52
53         /** Helper function trying to load one requested library */
54         public static void nativeInit(String name) {
55                 Throwable cause = null;
56                 try {
57                         /* Prefer the version of the library bundled into the jar file and use it */
58                         if (loadLibAsStream(name))
59                                 return;
60                 } catch (UnsatisfiedLinkError|SecurityException|IOException e) {
61                         cause = e;
62                 }
63                 
64                 /* If not found, try to see if we can find a version on disk */
65                 try {
66                         System.loadLibrary(name);
67                         return;
68                 } catch (UnsatisfiedLinkError systemException) { /* don't care */ }
69                 
70                 System.err.println("\nCannot load the bindings to the "+name+" library in path "+getPath()+" and no usable SimGrid installation found on disk.");
71                 if (cause != null) {
72                         if (cause.getMessage().matches(".*libcgraph.so.*"))
73                                 System.err.println("HINT: Try to install the libcgraph package (sudo apt-get install libcgraph).");
74                         else if (cause.getMessage().matches(".*libboost_context.so.*"))
75                                 System.err.println("HINT: Try to install the boost-context package (sudo apt-get install libboost-context-dev).");
76                         else
77                                 System.err.println("Try to install the missing dependencies, if any. Read carefully the following error message.");
78
79                         System.err.println();
80                         cause.printStackTrace();
81                 } else {
82                         System.err.println("This jar file does not seem to fit your system, and no usable SimGrid installation found on disk.");
83                 }
84                 System.exit(1);
85         }
86
87         /** Try to extract the library from the jarfile before loading it */
88         private static boolean loadLibAsStream (String name) throws IOException, UnsatisfiedLinkError {
89                 String path = NativeLib.getPath();
90                 
91                 // We must write the lib onto the disk before loading it -- stupid operating systems
92                 if (tempDir == null) {
93                         tempDir = Files.createTempDirectory("simgrid-java-");
94                         // don't leak the files on disk, but remove it on JVM shutdown
95                         Runtime.getRuntime().addShutdownHook(new Thread(new FileCleaner(tempDir.toFile())));
96                 }
97                 
98                 /* For each possible filename of the given library on all possible OSes, try it */
99                 for (String filename : new String[] 
100                    { name, 
101                      "lib"+name+".so",               /* linux */
102                      name+".dll", "lib"+name+".dll", /* windows (pure and mingw) */
103                      "lib"+name+".dylib"             /* mac osx */}) {
104                                                 
105                         File fileOut = new File(tempDir.toFile().getAbsolutePath() + File.separator + filename);
106                         try ( // Try-with-resources. These stream will be autoclosed when needed.
107                                 InputStream in = NativeLib.class.getClassLoader().getResourceAsStream(path+filename);
108                                 OutputStream out = new FileOutputStream(fileOut);
109                         ) {
110                                 if (in == null)
111                                         continue; // Try the next name: no such file found
112                                 
113                                 /* copy the library in position */  
114                                 byte[] buffer = new byte[4096]; 
115                                 int bytesRead; 
116                                 while ((bytesRead = in.read(buffer)) != -1)     // Read until EOF
117                                         out.write(buffer, 0, bytesRead); 
118                                 
119                                 out.close(); // Windows cannot open it twice, so close it first. Shame.
120                                 
121                                 /* load that shit */
122                                 System.load(fileOut.getAbsolutePath());
123                                 
124                                 /* It loaded! we're good */
125                                 return true;
126                                 
127                         }
128                 }
129                 
130                 /* No suitable name found */
131                 return false;
132         }
133
134         /** Find where to search for the library in the jar -- keep it aligned with where cmake puts it! */
135         private static String getPath() {
136                 // Inspiration: https://github.com/xerial/snappy-java/blob/develop/src/main/java/org/xerial/snappy/OSInfo.java
137                 String prefix = "NATIVE";
138                 String os = System.getProperty("os.name");
139                 String arch = System.getProperty("os.arch");
140
141                 if (arch.matches("^i[3-6]86$"))
142                         arch = "x86";
143                 else if ("x86_64".equalsIgnoreCase(arch) || "AMD64".equalsIgnoreCase(arch))
144                         arch = "amd64";
145
146                 if (os.toLowerCase().startsWith("win")){
147                         os = "Windows";
148                 } else if (os.contains("OS X"))
149                         os = "Darwin";
150
151                 os = os.replace(' ', '_');
152                 arch = arch.replace(' ', '_');
153
154                 return prefix + "/" + os + "/" + arch + "/";
155         }
156         
157         /** A hackish mechanism used to remove the file containing our library when the JVM shuts down */
158         private static class FileCleaner implements Runnable {
159                 private File dir;
160                 public FileCleaner(File dir) {
161                         this.dir = dir;
162                 }
163                 @Override
164                 public void run() {
165                         try {
166                                 for (File f : dir.listFiles())
167                                         if (! f.delete() )
168                                                 System.out.println("Unable to clean temporary file "+f.getAbsolutePath()+" during shutdown.");
169                                 if (! dir.delete() )
170                                         System.out.println("Unable to clean temporary file "+dir.getAbsolutePath()+" during shutdown.");                                
171                         } catch(Exception e) {
172                                 System.out.println("Unable to clean temporary file "+dir.getAbsolutePath()+" during shutdown: "+e.getCause());
173                                 e.printStackTrace();
174                         }
175                 }
176         }
177 }