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More ClassLoader fixes for #277
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@Spasi
Spasi committed Feb 16, 2017
1 parent 97604f9 commit 141c75b
Showing 1 changed file with 47 additions and 21 deletions.
68 changes: 47 additions & 21 deletions modules/core/src/main/java/org/lwjgl/system/Library.java
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Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,8 @@ public final class Library {

private static final Pattern NATIVES_JAR = Pattern.compile("/[\\w-]+?-natives-\\w+.jar!/");

private static final SystemLibraryLoader SYSTEM_LIBRARY_LOADER;

static {
if ( DEBUG ) {
apiLog("Version: " + Version.getVersion());
Expand All @@ -50,6 +52,8 @@ public final class Library {
);
}

SYSTEM_LIBRARY_LOADER = getSystemLibraryLoader();

loadSystem(Library.class, JNI_LIBRARY_NAME);
}

Expand Down Expand Up @@ -90,7 +94,7 @@ public static void loadSystem(Class<?> context, String name) throws UnsatisfiedL
// METHOD 2: org.lwjgl.librarypath
URL libURL = context.getResource("/" + libName);
if ( libURL == null ) {
if ( loadSystem(libName, Configuration.LIBRARY_PATH) )
if ( loadSystem(context, libName, Configuration.LIBRARY_PATH) )
return;
} else {
// Always use the SLL if the library is found in the classpath,
Expand All @@ -101,7 +105,7 @@ public static void loadSystem(Class<?> context, String name) throws UnsatisfiedL
apiLog("\tUsing SharedLibraryLoader...");
// Extract from classpath and try org.lwjgl.librarypath
try ( FileChannel ignored = SharedLibraryLoader.load(name, libName, libURL) ) {
if ( loadSystem(libName, Configuration.LIBRARY_PATH) )
if ( loadSystem(context, libName, Configuration.LIBRARY_PATH) )
return;
}
} catch (Exception e) {
Expand All @@ -112,15 +116,15 @@ public static void loadSystem(Class<?> context, String name) throws UnsatisfiedL

// METHOD 3: System.loadLibrary
try {
System.loadLibrary(name);
SYSTEM_LIBRARY_LOADER.loadLibrary(context, name);

// Success, but java.library.path might be still empty, or not include the library.
// In that case, ClassLoader::findLibrary was used to return the library path (e.g. OSGi does this with native libraries in bundles).
String paths = System.getProperty(JAVA_LIBRARY_PATH);
Path libFile = paths == null ? null : findLibrary(paths, libName);
if ( libFile != null ) {
apiLog(String.format("\tLoaded from %s: %s", JAVA_LIBRARY_PATH, libFile));
checkHash(libFile);
checkHash(context, libFile);
} else
apiLog("\tLoaded from a ClassLoader provided path.");
return;
Expand All @@ -132,12 +136,12 @@ public static void loadSystem(Class<?> context, String name) throws UnsatisfiedL
throw new UnsatisfiedLinkError("Failed to locate library: " + libName);
}

private static boolean loadSystem(String libName, Configuration<String> property) {
private static boolean loadSystem(Class<?> context, String libName, Configuration<String> property) {
String paths = property.get();
return paths != null && loadSystem(libName, property.getProperty(), paths);
return paths != null && loadSystem(context, libName, property.getProperty(), paths);
}

private static boolean loadSystem(String libName, String property, String paths) {
private static boolean loadSystem(Class<?> context, String libName, String property, String paths) {
Path libFile = findLibrary(paths, libName);
if ( libFile == null ) {
apiLog(String.format("\t%s not found in %s=%s", libName, property, paths));
Expand All @@ -146,7 +150,7 @@ private static boolean loadSystem(String libName, String property, String paths)

System.load(libFile.toAbsolutePath().toString());
apiLog(String.format("\tLoaded from %s: %s", property, libFile));
checkHash(libFile);
checkHash(context, libFile);
return true;
}

Expand Down Expand Up @@ -203,7 +207,7 @@ public static SharedLibrary loadNative(Class<?> context, String name, boolean bu
// METHOD 2: org.lwjgl.librarypath
URL libURL = context.getResource("/" + libName);
if ( libURL == null ) {
lib = loadNative(libName, Configuration.LIBRARY_PATH);
lib = loadNative(context, libName, Configuration.LIBRARY_PATH);
if ( lib != null )
return lib;
} else {
Expand All @@ -215,7 +219,7 @@ public static SharedLibrary loadNative(Class<?> context, String name, boolean bu
apiLog("\tUsing SharedLibraryLoader...");
// Extract from classpath and try org.lwjgl.librarypath
try ( FileChannel ignored = SharedLibraryLoader.load(name, libName, libURL) ) {
return loadNative(libName, Configuration.LIBRARY_PATH);
return loadNative(context, libName, Configuration.LIBRARY_PATH);
}
} catch (Exception e) {
if ( debugLoader )
Expand Down Expand Up @@ -245,7 +249,7 @@ public static SharedLibrary loadNative(Class<?> context, String name, boolean bu
// Then java.library.path
String paths = System.getProperty(JAVA_LIBRARY_PATH);
if ( paths != null ) {
lib = loadNative(libName, JAVA_LIBRARY_PATH, paths);
lib = loadNative(context, libName, JAVA_LIBRARY_PATH, paths);
if ( lib != null )
return lib;
}
Expand All @@ -264,17 +268,17 @@ public static SharedLibrary loadNative(Class<?> context, String name, boolean bu
throw new UnsatisfiedLinkError("Failed to locate library: " + libName);
}

private static SharedLibrary loadNative(String libName, Configuration<String> property) {
private static SharedLibrary loadNative(Class<?> context, String libName, Configuration<String> property) {
String paths = property.get();
if ( paths != null ) {
SharedLibrary lib = loadNative(libName, property.getProperty(), paths);
SharedLibrary lib = loadNative(context, libName, property.getProperty(), paths);
if ( lib != null )
return lib;
}
return null;
}

private static SharedLibrary loadNative(String libName, String property, String paths) {
private static SharedLibrary loadNative(Class<?> context, String libName, String property, String paths) {
Path libFile = findLibrary(paths, libName);
if ( libFile == null ) {
apiLog(String.format("\t%s not found in %s=%s", libName, property, paths));
Expand All @@ -283,7 +287,7 @@ private static SharedLibrary loadNative(String libName, String property, String

SharedLibrary lib = apiCreateLibrary(libFile.toString());
apiLog(String.format("\tLoaded from %s: %s", property, libFile));
checkHash(libFile);
checkHash(context, libFile);
return lib;
}

Expand Down Expand Up @@ -338,9 +342,9 @@ private static void printError(boolean bundledWithLWJGL) {
DEBUG_STREAM.println(
"[LWJGL] Failed to load a library. Possible solutions:\n" + (bundledWithLWJGL
? "\ta) Add the directory that contains the shared library to -Djava.library.path or -Dorg.lwjgl.librarypath.\n" +
"\tb) Add the JAR that contains the shared library to the classpath."
"\tb) Add the JAR that contains the shared library to the classpath."
: "\ta) Install the library or the driver that provides the library.\n" +
"\tb) Ensure that the library is accessible from the system library paths."
"\tb) Ensure that the library is accessible from the system library paths."
)
);

Expand All @@ -356,17 +360,18 @@ private static void printError(boolean bundledWithLWJGL) {
*
* <p>This check prints a simple warning when there's a hash mismatch, to help diagnose installation/classpath issues. It is not a security feature.</p>
*
* @param context the class to use to discover the shared library hash in the classpath
* @param libFile the library file loaded
*/
private static void checkHash(Path libFile) {
private static void checkHash(Class<?> context, Path libFile) {
if ( !CHECKS )
return;

try {
URL classesURL = null;
URL nativesURL = null;

Enumeration<URL> resources = Library.class.getClassLoader().getResources(libFile.getFileName() + ".sha1");
Enumeration<URL> resources = context.getClassLoader().getResources(libFile.getFileName() + ".sha1");
while ( resources.hasMoreElements() ) {
URL url = resources.nextElement();
if ( NATIVES_JAR.matcher(url.toExternalForm()).find() )
Expand All @@ -384,10 +389,10 @@ private static void checkHash(Path libFile) {

if ( !Arrays.equals(expected, actual) )
DEBUG_STREAM.println("[LWJGL] [WARNING] Mismatch detected between the Java and native libraries.");
} catch (Exception e) {
} catch (Throwable t) {
if ( DEBUG ) {
apiLog("Failed to verify native library.");
e.printStackTrace();
t.printStackTrace();
}
}
}
Expand All @@ -411,4 +416,25 @@ private static byte[] getSHA1(Path libFile) throws NoSuchAlgorithmException, IOE
return digest.digest();
}

private interface SystemLibraryLoader {
void loadLibrary(Class<?> context, String libname) throws Throwable;
}

private static SystemLibraryLoader getSystemLibraryLoader() {
try {
// Try to use Runtime.getRuntime().loadLibrary0 so that the correct ClassLoader is used, based on the class context.
try {
Method loadLibrary0 = Runtime.getRuntime().getClass().getDeclaredMethod("loadLibrary0", Class.class, String.class);
loadLibrary0.setAccessible(true);
return loadLibrary0::invoke;
} catch (NoSuchMethodException ignored) {
Method loadLibrary0 = Runtime.getRuntime().getClass().getDeclaredMethod("loadLibrary0", ClassLoader.class, String.class);
loadLibrary0.setAccessible(true);
return (context, libName) -> loadLibrary0.invoke(context.getClassLoader(), libName);
}
} catch (Exception ignored) {
return (context, libName) -> System.loadLibrary(libName);
}
}

}

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