org.jikesrvm.runtime
Class DynamicLibrary

java.lang.Object
  org.jikesrvm.runtime.DynamicLibrary

public final class DynamicLibrary
extends Object

Interface to the dynamic libraries of our underlying operating system.

dynamicLibraries

private static final ImmutableEntryHashMapRVM<String,DynamicLibrary> dynamicLibraries

Currently loaded dynamic libraries.

libName

private final String libName

The name of the library

libHandler

private final Address libHandler

Value returned from dlopen

jniOnLoad

private final Address jniOnLoad

Address of JNI_OnLoad method

jniOnUnload

private final Address jniOnUnload

Address of JNI_OnUnLoad

DynamicLibrary

private DynamicLibrary(String libraryName)

Load a dynamic library and maintain it in this object.

Parameters:

libraryName - library name

boot

public static void boot()

Add symbol for the boot image runner to find symbols within it.

getJNI_OnLoad

private Address getJNI_OnLoad()

Get the unique JNI_OnLoad symbol associated with this library

Returns:

JNI_OnLoad address or zero if not present

getJNI_OnUnload

private Address getJNI_OnUnload()

Get the unique JNI_OnUnload symbol associated with this library

Returns:

JNI_OnUnload address or zero if not present

callOnLoad

private void callOnLoad()

Called after we've successfully loaded the shared library

runJNI_OnLoad

private static int runJNI_OnLoad(Address JNI_OnLoadAddress)

Method call to run the onload method. Performed as a native method as the JNI_OnLoad method may contain JNI calls and we need the RVMThread of the JNIEnv to be correctly populated (this wouldn't happen with a SysCall)

Parameters:

JNI_OnLoadAddress - address of JNI_OnLoad function

Returns:

the JNI version returned by the JNI_OnLoad function

checkJNIVersion

private static void checkJNIVersion(int version)

Check JNI version is ≤ 1.4 and if not throw an UnsatisfiedLinkError

Parameters:

version - to check

getLibName

public String getLibName()

Returns:

the true name of the dynamic library

getSymbol

public Address getSymbol(String symbolName)

look up this dynamic library for a symbol

Parameters:

symbolName - symbol name

Returns:

The Address of the symbol system handler (actually an address to an AixLinkage triplet). (-1: not found or couldn't be created)

unload

public void unload()

unload a dynamic library

clean

public void clean()

Tell the operating system to remove the dynamic library from the system space.

toString

public String toString()

Overrides:

toString in class Object

load

public static int load(String libname)

Load a dynamic library

Parameters:

libname - the name of the library to load.

Returns:

0 on failure, 1 on success

resolveSymbol

public static Address resolveSymbol(String symbol)

Resolve a symbol to an address in a currently loaded dynamic library.

Returns:

the address of the symbol of Address.zero() if it cannot be resolved