001// --- BEGIN LICENSE BLOCK ---
002/* 
003 * Copyright (c) 2009, Mikio L. Braun
004 * All rights reserved.
005 * 
006 * Redistribution and use in source and binary forms, with or without
007 * modification, are permitted provided that the following conditions are
008 * met:
009 * 
010 *     * Redistributions of source code must retain the above copyright
011 *       notice, this list of conditions and the following disclaimer.
012 * 
013 *     * Redistributions in binary form must reproduce the above
014 *       copyright notice, this list of conditions and the following
015 *       disclaimer in the documentation and/or other materials provided
016 *       with the distribution.
017 * 
018 *     * Neither the name of the Technische Universit?t Berlin nor the
019 *       names of its contributors may be used to endorse or promote
020 *       products derived from this software without specific prior
021 *       written permission.
022 * 
023 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
024 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
025 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
026 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
027 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
028 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
029 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
030 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
031 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
032 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
033 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
034 */
035// --- END LICENSE BLOCK ---
036package org.jblas.util;
037
038import java.io.*;
039
040/**
041 * Class which allows to load a dynamic file as resource (for example, from a 
042 * jar-file)
043 */
044public class LibraryLoader {
045
046    private Logger logger;
047    private String libpath;
048    
049    public LibraryLoader() {
050        logger = Logger.getLogger();
051        libpath = null;
052    }
053
054    /**
055     * <p>Find the library <tt>libname</tt> as a resource, copy it to a tempfile
056     * and load it using System.load(). The name of the library has to be the
057     * base name, it is mapped to the corresponding system name using
058     * System.mapLibraryName(). For example, the library "foo" is called "libfoo.so"
059     * under Linux and "foo.dll" under Windows, but you just have to pass "foo"
060     * the loadLibrary().</p>
061     *
062     * <p>I'm not quite sure if this doesn't open all kinds of security holes. Any ideas?</p>
063     *
064     * <p>This function reports some more information to the "org.jblas" logger at
065     * the FINE level.</p>
066     *
067     * @param libname basename of the library
068     * @throws UnsatisfiedLinkError if library cannot be founds
069     */
070    public void loadLibrary(String libname, boolean withFlavor) {
071        // preload flavor libraries
072        String flavor = null;
073        if (withFlavor) {
074            logger.debug("Preloading ArchFlavor library.");
075            flavor = ArchFlavor.archFlavor();
076        }
077
078        libname = System.mapLibraryName(libname);
079        logger.debug("Attempting to load \"" + libname + "\".");
080
081        String[] paths = {
082            "/",
083            "/bin/",
084            fatJarLibraryPath("static", flavor),
085            fatJarLibraryPathNonUnified("static", flavor),
086            fatJarLibraryPath("dynamic", flavor),
087            fatJarLibraryPathNonUnified("dynamic", flavor),
088        };
089
090        InputStream is = findLibrary(paths, libname);
091
092        // Oh man, have to get out of here!
093        if (is == null) {
094            throw new UnsatisfiedLinkError("Couldn't find the resource " + libname + ".");
095        }
096
097        logger.config("Loading " + libname + " from " + libpath + ".");
098        loadLibraryFromStream(libname, is);
099    }
100
101    private InputStream findLibrary(String[] paths, String libname) {
102        InputStream is = null;
103        for (String path: paths) {
104            is = tryPath(path + libname);
105            if (is != null) {
106                libpath = path;
107                break;
108            }
109        }
110        return is;
111    }
112
113    /** Translate all those Windows to "Windows". ("Windows XP", "Windows Vista", "Windows 7", etc.) */
114    private String unifyOSName(String osname) {
115        if (osname.startsWith("Windows")) {
116            return "Windows";
117        }
118        return osname;
119    }
120
121    /** Compute the path to the library. The path is basically
122    "/" + os.name + "/" + os.arch + "/" + libname. */
123    private String fatJarLibraryPath(String linkage, String flavor) {
124        String sep = "/"; //System.getProperty("file.separator");
125        String os_name = unifyOSName(System.getProperty("os.name"));
126        String os_arch = System.getProperty("os.arch");
127        String path = sep + "lib" + sep + linkage + sep + os_name + sep + os_arch + sep;
128        if (null != flavor)
129            path += flavor + sep;
130        return path;
131    }
132
133    /** Full path without the OS name non-unified. */
134    private String fatJarLibraryPathNonUnified(String linkage, String flavor) {
135        String sep = "/"; //System.getProperty("file.separator");
136        String os_name = System.getProperty("os.name");
137        String os_arch = System.getProperty("os.arch");
138        String path = sep + "lib" + sep + linkage + sep + os_name + sep + os_arch + sep;
139        if (null != flavor)
140            path += flavor + sep;
141        return path;
142    }
143
144    /** Try to open a file at the given position. */
145    private InputStream tryPath(String path) {
146        Logger.getLogger().debug("Trying path \"" + path + "\".");
147        return getClass().getResourceAsStream(path);
148    }
149
150    /** Load a system library from a stream. Copies the library to a temp file
151     * and loads from there.
152     */
153    private void loadLibraryFromStream(String libname, InputStream is) {
154        try {
155            File tempfile = File.createTempFile("jblas", libname);
156            tempfile.deleteOnExit();
157            OutputStream os = new FileOutputStream(tempfile);
158
159            logger.debug("tempfile.getPath() = " + tempfile.getPath());
160
161            long savedTime = System.currentTimeMillis();
162
163            byte buf[] = new byte[1024];
164            int len;
165            while ((len = is.read(buf)) > 0) {
166                os.write(buf, 0, len);
167            }
168
169            double seconds = (double) (System.currentTimeMillis() - savedTime) / 1e3;
170            logger.debug("Copying took " + seconds + " seconds.");
171
172            os.close();
173
174            System.load(tempfile.getPath());
175        } catch (IOException io) {
176            logger.error("Could not create the temp file: " + io.toString() + ".\n");
177        } catch (UnsatisfiedLinkError ule) {
178            logger.error("Couldn't load copied link file: " + ule.toString() + ".\n");
179        }
180    }
181}