e046c56eee
2006-06-16 Andrew Haley <aph@redhat.com> * class.c (make_class_data): When using flag_indirect_classes, don't initialize the vtable of Class instances. 2006-06-16 Andrew Haley <aph@redhat.com> * java/lang/natClassLoader.cc (_Jv_NewClassFromInitializer): Don't copy the whole Class instance from the initializer: instead, copy everything but the first word (the vtable pointer). Change prototype to (const char* class_initializer). (_Jv_RegisterNewClasses): Change prototype to (const char**). * java/lang/Class.h (_Jv_RegisterNewClasses): Change prototype to (const char**). From-SVN: r114714
616 lines
17 KiB
C++
616 lines
17 KiB
C++
// natClassLoader.cc - Implementation of java.lang.ClassLoader native methods.
|
||
|
||
/* Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation
|
||
|
||
This file is part of libgcj.
|
||
|
||
This software is copyrighted work licensed under the terms of the
|
||
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
|
||
details. */
|
||
|
||
/* Author: Kresten Krab Thorup <krab@gnu.org> */
|
||
|
||
#include <config.h>
|
||
|
||
#include <stdlib.h>
|
||
#include <stdio.h>
|
||
#include <string.h>
|
||
|
||
#include <gcj/cni.h>
|
||
#include <jvm.h>
|
||
#include <execution.h>
|
||
|
||
#include <java-threads.h>
|
||
#include <java-interp.h>
|
||
|
||
#include <java/lang/Character.h>
|
||
#include <java/lang/Thread.h>
|
||
#include <java/lang/ClassLoader.h>
|
||
#include <java/lang/InternalError.h>
|
||
#include <java/lang/IllegalAccessError.h>
|
||
#include <java/lang/LinkageError.h>
|
||
#include <java/lang/NoClassDefFoundError.h>
|
||
#include <java/lang/ClassNotFoundException.h>
|
||
#include <java/lang/ClassCircularityError.h>
|
||
#include <java/lang/IncompatibleClassChangeError.h>
|
||
#include <java/lang/ClassFormatError.h>
|
||
#include <java/lang/VirtualMachineError.h>
|
||
#include <java/lang/VMClassLoader.h>
|
||
#include <java/lang/reflect/Modifier.h>
|
||
#include <java/lang/Runtime.h>
|
||
#include <java/lang/StringBuffer.h>
|
||
#include <java/io/Serializable.h>
|
||
#include <java/lang/Cloneable.h>
|
||
#include <java/util/HashMap.h>
|
||
#include <gnu/gcj/runtime/BootClassLoader.h>
|
||
#include <gnu/gcj/runtime/SystemClassLoader.h>
|
||
|
||
// Size of local hash table.
|
||
#define HASH_LEN 1013
|
||
|
||
// Hash function for Utf8Consts.
|
||
#define HASH_UTF(Utf) ((Utf)->hash16() % HASH_LEN)
|
||
|
||
// This records classes which will be registered with the system class
|
||
// loader when it is initialized.
|
||
static jclass system_class_list;
|
||
|
||
// This is used as the value of system_class_list after we have
|
||
// initialized the system class loader; it lets us know that we should
|
||
// no longer pay attention to the system abi flag.
|
||
#define SYSTEM_LOADER_INITIALIZED ((jclass) -1)
|
||
|
||
static jclass loaded_classes[HASH_LEN];
|
||
|
||
// This is the root of a linked list of classes
|
||
static jclass stack_head;
|
||
|
||
// While bootstrapping we keep a list of classes we found, so that we
|
||
// can register their packages. There aren't many of these so we
|
||
// just keep a small buffer here and abort if we overflow.
|
||
#define BOOTSTRAP_CLASS_LIST_SIZE 20
|
||
static jclass bootstrap_class_list[BOOTSTRAP_CLASS_LIST_SIZE];
|
||
static int bootstrap_index;
|
||
|
||
|
||
|
||
|
||
jclass
|
||
java::lang::ClassLoader::loadClassFromSig(jstring name)
|
||
{
|
||
int len = _Jv_GetStringUTFLength (name);
|
||
char sig[len + 1];
|
||
_Jv_GetStringUTFRegion (name, 0, name->length(), sig);
|
||
jclass result = _Jv_FindClassFromSignature(sig, this);
|
||
if (result == NULL)
|
||
throw new ClassNotFoundException(name);
|
||
return result;
|
||
}
|
||
|
||
|
||
|
||
// This tries to find a class in our built-in cache. This cache is
|
||
// used only for classes which are linked in to the executable or
|
||
// loaded via dlopen().
|
||
jclass
|
||
_Jv_FindClassInCache (_Jv_Utf8Const *name)
|
||
{
|
||
JvSynchronize sync (&java::lang::Class::class$);
|
||
jint hash = HASH_UTF (name);
|
||
|
||
jclass klass;
|
||
for (klass = loaded_classes[hash]; klass; klass = klass->next_or_version)
|
||
{
|
||
if (_Jv_equalUtf8Consts (name, klass->name))
|
||
break;
|
||
}
|
||
|
||
return klass;
|
||
}
|
||
|
||
void
|
||
_Jv_UnregisterClass (jclass the_class)
|
||
{
|
||
// This can happen if the class could not be defined properly.
|
||
if (! the_class->name)
|
||
return;
|
||
|
||
JvSynchronize sync (&java::lang::Class::class$);
|
||
jint hash = HASH_UTF(the_class->name);
|
||
|
||
jclass *klass = &(loaded_classes[hash]);
|
||
for ( ; *klass; klass = &((*klass)->next_or_version))
|
||
{
|
||
if (*klass == the_class)
|
||
{
|
||
*klass = (*klass)->next_or_version;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
// Register an initiating class loader for a given class.
|
||
void
|
||
_Jv_RegisterInitiatingLoader (jclass klass, java::lang::ClassLoader *loader)
|
||
{
|
||
if (! loader)
|
||
loader = java::lang::VMClassLoader::bootLoader;
|
||
if (! loader)
|
||
{
|
||
// Very early in the bootstrap process, the Bootstrap classloader may
|
||
// not exist yet.
|
||
// FIXME: We could maintain a list of these and come back and register
|
||
// them later.
|
||
return;
|
||
}
|
||
loader->loadedClasses->put(klass->name->toString(), klass);
|
||
}
|
||
|
||
// If we found an error while defining an interpreted class, we must
|
||
// go back and unregister it.
|
||
void
|
||
_Jv_UnregisterInitiatingLoader (jclass klass, java::lang::ClassLoader *loader)
|
||
{
|
||
if (! loader)
|
||
loader = java::lang::VMClassLoader::bootLoader;
|
||
loader->loadedClasses->remove(klass->name->toString());
|
||
}
|
||
|
||
|
||
// Class registration.
|
||
//
|
||
// There are two kinds of functions that register classes.
|
||
//
|
||
// Type 1:
|
||
//
|
||
// These take the address of a class that is in an object file.
|
||
// Because these classes are not allocated on the heap, It is also
|
||
// necessary to register the address of the object for garbage
|
||
// collection. This is used with the "old" C++ ABI and with
|
||
// -findirect-dispatch -fno-indirect-classes.
|
||
//
|
||
// Type 2:
|
||
//
|
||
// These take an initializer struct, create the class, and return the
|
||
// address of the newly created class to their caller. These are used
|
||
// with -findirect-dispatch.
|
||
//
|
||
// _Jv_RegisterClasses() and _Jv_RegisterClasses_Counted() are
|
||
// functions of Type 1, and _Jv_NewClassFromInitializer() and
|
||
// _Jv_RegisterNewClasses() are of Type 2.
|
||
|
||
|
||
// This function is called many times during startup, before main() is
|
||
// run. At that point in time we know for certain we are running
|
||
// single-threaded, so we don't need to lock when adding classes to the
|
||
// class chain. At all other times, the caller should synchronize on
|
||
// Class::class$.
|
||
void
|
||
_Jv_RegisterClasses (const jclass *classes)
|
||
{
|
||
_Jv_RegisterLibForGc (classes);
|
||
|
||
for (; *classes; ++classes)
|
||
{
|
||
jclass klass = *classes;
|
||
|
||
if (_Jv_CheckABIVersion ((unsigned long) klass->next_or_version))
|
||
(*_Jv_RegisterClassHook) (klass);
|
||
}
|
||
}
|
||
|
||
// This is a version of _Jv_RegisterClasses that takes a count.
|
||
void
|
||
_Jv_RegisterClasses_Counted (const jclass * classes, size_t count)
|
||
{
|
||
size_t i;
|
||
|
||
_Jv_RegisterLibForGc (classes);
|
||
|
||
for (i = 0; i < count; i++)
|
||
{
|
||
jclass klass = classes[i];
|
||
|
||
if (_Jv_CheckABIVersion ((unsigned long) klass->next_or_version))
|
||
(*_Jv_RegisterClassHook) (klass);
|
||
}
|
||
}
|
||
|
||
// Create a class on the heap from an initializer struct.
|
||
jclass
|
||
_Jv_NewClassFromInitializer (const char *class_initializer)
|
||
{
|
||
/* We create an instance of java::lang::Class and copy all of its
|
||
fields except the first word (the vtable pointer) from
|
||
CLASS_INITIALIZER. This first word is pre-initialized by
|
||
_Jv_AllocObj, and we don't want to overwrite it. */
|
||
|
||
jclass new_class
|
||
= (jclass)_Jv_AllocObj (sizeof (java::lang::Class),
|
||
&java::lang::Class::class$);
|
||
const char *src = class_initializer + sizeof (void*);
|
||
char *dst = (char*)new_class + sizeof (void*);
|
||
size_t len = sizeof (*new_class) - sizeof (void*);
|
||
memcpy (dst, src, len);
|
||
|
||
new_class->engine = &_Jv_soleIndirectCompiledEngine;
|
||
|
||
if (_Jv_CheckABIVersion ((unsigned long) new_class->next_or_version))
|
||
(*_Jv_RegisterClassHook) (new_class);
|
||
|
||
return new_class;
|
||
}
|
||
|
||
// Called by compiler-generated code at DSO initialization. CLASSES
|
||
// is an array of pairs: the first item of each pair is a pointer to
|
||
// the initialized data that is a class initializer in a DSO, and the
|
||
// second is a pointer to a class reference.
|
||
// _Jv_NewClassFromInitializer() creates the new class (on the Java
|
||
// heap) and we write the address of the new class into the address
|
||
// pointed to by the second word.
|
||
void
|
||
_Jv_RegisterNewClasses (char **classes)
|
||
{
|
||
_Jv_InitGC ();
|
||
|
||
const char *initializer;
|
||
|
||
while ((initializer = *classes++))
|
||
{
|
||
jclass *class_ptr = (jclass *)*classes++;
|
||
*class_ptr = _Jv_NewClassFromInitializer (initializer);
|
||
}
|
||
}
|
||
|
||
void
|
||
_Jv_RegisterClassHookDefault (jclass klass)
|
||
{
|
||
// This is bogus, but there doesn't seem to be a better place to do
|
||
// it.
|
||
if (! klass->engine)
|
||
klass->engine = &_Jv_soleCompiledEngine;
|
||
|
||
if (system_class_list != SYSTEM_LOADER_INITIALIZED)
|
||
{
|
||
unsigned long abi = (unsigned long) klass->next_or_version;
|
||
if (! _Jv_ClassForBootstrapLoader (abi))
|
||
{
|
||
klass->next_or_version = system_class_list;
|
||
system_class_list = klass;
|
||
return;
|
||
}
|
||
}
|
||
|
||
jint hash = HASH_UTF (klass->name);
|
||
|
||
// If the class is already registered, don't re-register it.
|
||
for (jclass check_class = loaded_classes[hash];
|
||
check_class != NULL;
|
||
check_class = check_class->next_or_version)
|
||
{
|
||
if (check_class == klass)
|
||
{
|
||
// If you get this, it means you have the same class in two
|
||
// different libraries.
|
||
#define TEXT "Duplicate class registration: "
|
||
// We size-limit MESSAGE so that you can't trash the stack.
|
||
char message[200];
|
||
strcpy (message, TEXT);
|
||
strncpy (message + sizeof (TEXT) - 1, klass->name->chars(),
|
||
sizeof (message) - sizeof (TEXT));
|
||
message[sizeof (message) - 1] = '\0';
|
||
if (! gcj::runtimeInitialized)
|
||
JvFail (message);
|
||
else
|
||
{
|
||
java::lang::String *str = JvNewStringLatin1 (message);
|
||
throw new java::lang::VirtualMachineError (str);
|
||
}
|
||
}
|
||
}
|
||
|
||
klass->next_or_version = loaded_classes[hash];
|
||
loaded_classes[hash] = klass;
|
||
}
|
||
|
||
// A pointer to a function that actually registers a class.
|
||
// Normally _Jv_RegisterClassHookDefault, but could be some other function
|
||
// that registers the class in e.g. a ClassLoader-local table.
|
||
// Should synchronize on Class:class$ while setting/restore this variable.
|
||
|
||
void (*_Jv_RegisterClassHook) (jclass cl) = _Jv_RegisterClassHookDefault;
|
||
|
||
void
|
||
_Jv_RegisterClass (jclass klass)
|
||
{
|
||
jclass classes[2];
|
||
classes[0] = klass;
|
||
classes[1] = NULL;
|
||
_Jv_RegisterClasses (classes);
|
||
}
|
||
|
||
// This is used during initialization to register all compiled-in
|
||
// classes that are not part of the core with the system class loader.
|
||
void
|
||
_Jv_CopyClassesToSystemLoader (gnu::gcj::runtime::SystemClassLoader *loader)
|
||
{
|
||
for (jclass klass = system_class_list;
|
||
klass;
|
||
klass = klass->next_or_version)
|
||
{
|
||
klass->loader = loader;
|
||
loader->addClass(klass);
|
||
}
|
||
system_class_list = SYSTEM_LOADER_INITIALIZED;
|
||
}
|
||
|
||
// An internal variant of _Jv_FindClass which simply swallows a
|
||
// NoClassDefFoundError or a ClassNotFoundException. This gives the
|
||
// caller a chance to evaluate the situation and behave accordingly.
|
||
jclass
|
||
_Jv_FindClassNoException (_Jv_Utf8Const *name, java::lang::ClassLoader *loader)
|
||
{
|
||
jclass klass;
|
||
|
||
try
|
||
{
|
||
klass = _Jv_FindClass(name, loader);
|
||
}
|
||
catch ( java::lang::NoClassDefFoundError *ncdfe )
|
||
{
|
||
return NULL;
|
||
}
|
||
catch ( java::lang::ClassNotFoundException *cnfe )
|
||
{
|
||
return NULL;
|
||
}
|
||
|
||
return klass;
|
||
}
|
||
|
||
jclass
|
||
_Jv_FindClass (_Jv_Utf8Const *name, java::lang::ClassLoader *loader)
|
||
{
|
||
// See if the class was already loaded by this loader. This handles
|
||
// initiating loader checks, as we register classes with their
|
||
// initiating loaders.
|
||
|
||
java::lang::ClassLoader *boot = java::lang::VMClassLoader::bootLoader;
|
||
java::lang::ClassLoader *real = loader;
|
||
if (! real)
|
||
real = boot;
|
||
jstring sname = name->toString();
|
||
// We might still be bootstrapping the VM, in which case there
|
||
// won't be a bootstrap class loader yet.
|
||
jclass klass = real ? real->findLoadedClass (sname) : NULL;
|
||
|
||
if (! klass)
|
||
{
|
||
if (loader)
|
||
{
|
||
// Load using a user-defined loader, jvmspec 5.3.2.
|
||
// Note that we explicitly must call the single-argument form.
|
||
klass = loader->loadClass(sname);
|
||
|
||
// If "loader" delegated the loadClass operation to another
|
||
// loader, explicitly register that it is also an initiating
|
||
// loader of the given class.
|
||
java::lang::ClassLoader *delegate = (loader == boot
|
||
? NULL
|
||
: loader);
|
||
if (klass && klass->getClassLoaderInternal () != delegate)
|
||
_Jv_RegisterInitiatingLoader (klass, loader);
|
||
}
|
||
else if (boot)
|
||
{
|
||
// Load using the bootstrap loader jvmspec 5.3.1.
|
||
klass = java::lang::VMClassLoader::loadClass (sname, false);
|
||
|
||
// Register that we're an initiating loader.
|
||
if (klass)
|
||
_Jv_RegisterInitiatingLoader (klass, 0);
|
||
}
|
||
else
|
||
{
|
||
// Not even a bootstrap loader, try the built-in cache.
|
||
klass = _Jv_FindClassInCache (name);
|
||
|
||
if (klass)
|
||
{
|
||
bool found = false;
|
||
for (int i = 0; i < bootstrap_index; ++i)
|
||
{
|
||
if (bootstrap_class_list[i] == klass)
|
||
{
|
||
found = true;
|
||
break;
|
||
}
|
||
}
|
||
if (! found)
|
||
{
|
||
if (bootstrap_index == BOOTSTRAP_CLASS_LIST_SIZE)
|
||
abort ();
|
||
bootstrap_class_list[bootstrap_index++] = klass;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
return klass;
|
||
}
|
||
|
||
void
|
||
_Jv_RegisterBootstrapPackages ()
|
||
{
|
||
for (int i = 0; i < bootstrap_index; ++i)
|
||
java::lang::VMClassLoader::definePackageForNative(bootstrap_class_list[i]->getName());
|
||
}
|
||
|
||
jclass
|
||
_Jv_NewClass (_Jv_Utf8Const *name, jclass superclass,
|
||
java::lang::ClassLoader *loader)
|
||
{
|
||
jclass ret = (jclass) _Jv_AllocObject (&java::lang::Class::class$);
|
||
ret->name = name;
|
||
ret->superclass = superclass;
|
||
ret->loader = loader;
|
||
|
||
_Jv_RegisterInitiatingLoader (ret, loader);
|
||
|
||
return ret;
|
||
}
|
||
|
||
static _Jv_IDispatchTable *array_idt = NULL;
|
||
static jshort array_depth = 0;
|
||
static jclass *array_ancestors = NULL;
|
||
|
||
static jclass interfaces[] =
|
||
{
|
||
&java::lang::Cloneable::class$,
|
||
&java::io::Serializable::class$
|
||
};
|
||
|
||
// Create a class representing an array of ELEMENT and store a pointer to it
|
||
// in element->arrayclass. LOADER is the ClassLoader which _initiated_ the
|
||
// instantiation of this array. ARRAY_VTABLE is the vtable to use for the new
|
||
// array class. This parameter is optional.
|
||
void
|
||
_Jv_NewArrayClass (jclass element, java::lang::ClassLoader *loader,
|
||
_Jv_VTable *array_vtable)
|
||
{
|
||
JvSynchronize sync (element);
|
||
|
||
_Jv_Utf8Const *array_name;
|
||
int len;
|
||
|
||
if (element->arrayclass)
|
||
return;
|
||
|
||
if (element->isPrimitive())
|
||
{
|
||
if (element == JvPrimClass (void))
|
||
throw new java::lang::ClassNotFoundException ();
|
||
len = 3;
|
||
}
|
||
else
|
||
len = element->name->len() + 5;
|
||
|
||
{
|
||
char signature[len];
|
||
int index = 0;
|
||
signature[index++] = '[';
|
||
// Compute name of array class.
|
||
if (element->isPrimitive())
|
||
{
|
||
signature[index++] = (char) element->method_count;
|
||
}
|
||
else
|
||
{
|
||
size_t length = element->name->len();
|
||
const char *const name = element->name->chars();
|
||
if (name[0] != '[')
|
||
signature[index++] = 'L';
|
||
memcpy (&signature[index], name, length);
|
||
index += length;
|
||
if (name[0] != '[')
|
||
signature[index++] = ';';
|
||
}
|
||
array_name = _Jv_makeUtf8Const (signature, index);
|
||
}
|
||
|
||
// Create new array class.
|
||
jclass array_class = _Jv_NewClass (array_name, &java::lang::Object::class$,
|
||
element->loader);
|
||
|
||
// Note that `vtable_method_count' doesn't include the initial
|
||
// gc_descr slot.
|
||
int dm_count = java::lang::Object::class$.vtable_method_count;
|
||
|
||
// Create a new vtable by copying Object's vtable.
|
||
_Jv_VTable *vtable;
|
||
if (array_vtable)
|
||
vtable = array_vtable;
|
||
else
|
||
vtable = _Jv_VTable::new_vtable (dm_count);
|
||
vtable->clas = array_class;
|
||
vtable->gc_descr = java::lang::Object::class$.vtable->gc_descr;
|
||
for (int i = 0; i < dm_count; ++i)
|
||
vtable->set_method (i, java::lang::Object::class$.vtable->get_method (i));
|
||
|
||
array_class->vtable = vtable;
|
||
array_class->vtable_method_count
|
||
= java::lang::Object::class$.vtable_method_count;
|
||
|
||
// Stash the pointer to the element type.
|
||
array_class->element_type = element;
|
||
|
||
// Register our interfaces.
|
||
array_class->interfaces = interfaces;
|
||
array_class->interface_count = sizeof interfaces / sizeof interfaces[0];
|
||
|
||
// Since all array classes have the same interface dispatch table, we can
|
||
// cache one and reuse it. It is not necessary to synchronize this.
|
||
if (!array_idt)
|
||
{
|
||
_Jv_Linker::wait_for_state(array_class, JV_STATE_PREPARED);
|
||
array_idt = array_class->idt;
|
||
array_depth = array_class->depth;
|
||
array_ancestors = array_class->ancestors;
|
||
}
|
||
else
|
||
{
|
||
array_class->idt = array_idt;
|
||
array_class->depth = array_depth;
|
||
array_class->ancestors = array_ancestors;
|
||
}
|
||
|
||
using namespace java::lang::reflect;
|
||
{
|
||
// Array classes are "abstract final" and inherit accessibility
|
||
// from element type, per vmspec 5.3.3.2
|
||
_Jv_ushort accflags = (Modifier::FINAL | Modifier::ABSTRACT
|
||
| (element->accflags
|
||
& (Modifier::PUBLIC | Modifier::PROTECTED
|
||
| Modifier::PRIVATE)));
|
||
array_class->accflags = accflags;
|
||
}
|
||
|
||
// An array class has no visible instance fields. "length" is invisible to
|
||
// reflection.
|
||
|
||
// Say this class is initialized and ready to go!
|
||
array_class->state = JV_STATE_DONE;
|
||
|
||
// vmspec, section 5.3.3 describes this
|
||
if (element->loader != loader)
|
||
_Jv_RegisterInitiatingLoader (array_class, loader);
|
||
|
||
element->arrayclass = array_class;
|
||
}
|
||
|
||
// These two functions form a stack of classes. When a class is loaded
|
||
// it is pushed onto the stack by the class loader; this is so that
|
||
// StackTrace can quickly determine which classes have been loaded.
|
||
|
||
jclass
|
||
_Jv_PopClass (void)
|
||
{
|
||
JvSynchronize sync (&java::lang::Class::class$);
|
||
if (stack_head)
|
||
{
|
||
jclass tmp = stack_head;
|
||
stack_head = tmp->chain;
|
||
return tmp;
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
void
|
||
_Jv_PushClass (jclass k)
|
||
{
|
||
JvSynchronize sync (&java::lang::Class::class$);
|
||
jclass tmp = stack_head;
|
||
stack_head = k;
|
||
k->chain = tmp;
|
||
}
|