/*
* Open up the reserved area and throw an exception. The reserved area
* should only be needed to create and initialize the exception itself.
*
* If we already opened it and we're continuing to overflow, abort the VM.
*
* We have to leave the "reserved" area open until the "catch" handler has
* finished doing its processing. This is because the catch handler may
* need to resolve classes, which requires calling into the class loader if
* the classes aren't already in the "initiating loader" list.
*/
void dvmHandleStackOverflow(Thread* self)
{
/*
* Can we make the reserved area available?
*/
if (self->stackOverflowed) {
/*
* Already did, nothing to do but bail.
*/
LOGE("DalvikVM: double-overflow of stack in threadid=%d; aborting\n",
self->threadId);
dvmDumpThread(self, false);
dvmAbort();
}
/* open it up to the full range */
LOGI("Stack overflow, expanding (%p to %p)\n", self->interpStackEnd,
self->interpStackStart - self->interpStackSize);
//dvmDumpThread(self, false);
self->interpStackEnd = self->interpStackStart - self->interpStackSize;
self->stackOverflowed = true;
/*
* If we were trying to throw an exception when the stack overflowed,
* we will blow up when doing the class lookup on StackOverflowError
* because of the pending exception. So, we clear it and make it
* the cause of the SOE.
*/
Object* excep = dvmGetException(self);
if (excep != NULL) {
LOGW("Stack overflow while throwing exception\n");
dvmClearException(self);
}
dvmThrowChainedException("Ljava/lang/StackOverflowError;", NULL, excep);
}
/*
* Throw the named exception using the dotted form of the class
* descriptor as the exception message, and with the specified cause.
*/
void dvmThrowChainedExceptionWithClassMessage(const char* exceptionDescriptor,
const char* messageDescriptor, Object* cause)
{
char* message = dvmDescriptorToDot(messageDescriptor);
dvmThrowChainedException(exceptionDescriptor, message, cause);
free(message);
}
/*
* Format the message into a small buffer and pass it along.
*/
void dvmThrowExceptionFmtV(const char* exceptionDescriptor, const char* fmt,
va_list args)
{
char msgBuf[512];
vsnprintf(msgBuf, sizeof(msgBuf), fmt, args);
dvmThrowChainedException(exceptionDescriptor, msgBuf, NULL);
}
/*
* Find a class by name, initializing it if requested.
*/
ClassObject* dvmFindClassByName(StringObject* nameObj, Object* loader,
bool doInit)
{
ClassObject* clazz = NULL;
char* name = NULL;
char* descriptor = NULL;
if (nameObj == NULL) {
dvmThrowException("Ljava/lang/NullPointerException;", NULL);
goto bail;
}
name = dvmCreateCstrFromString(nameObj);
/*
* We need to validate and convert the name (from x.y.z to x/y/z). This
* is especially handy for array types, since we want to avoid
* auto-generating bogus array classes.
*/
if (!validateClassName(name)) {
LOGW("dvmFindClassByName rejecting '%s'\n", name);
dvmThrowException("Ljava/lang/ClassNotFoundException;", name);
goto bail;
}
descriptor = dvmDotToDescriptor(name);
if (descriptor == NULL) {
goto bail;
}
if (doInit)
clazz = dvmFindClass(descriptor, loader);
else
clazz = dvmFindClassNoInit(descriptor, loader);
if (clazz == NULL) {
LOGVV("FAIL: load %s (%d)\n", descriptor, doInit);
Thread* self = dvmThreadSelf();
Object* oldExcep = dvmGetException(self);
dvmAddTrackedAlloc(oldExcep, self); /* don't let this be GCed */
dvmClearException(self);
dvmThrowChainedException("Ljava/lang/ClassNotFoundException;",
name, oldExcep);
dvmReleaseTrackedAlloc(oldExcep, self);
} else {
LOGVV("GOOD: load %s (%d) --> %p ldr=%p\n",
descriptor, doInit, clazz, clazz->classLoader);
}
bail:
free(name);
free(descriptor);
return clazz;
}
/*
* Open up the reserved area and throw an exception. The reserved area
* should only be needed to create and initialize the exception itself.
*
* If we already opened it and we're continuing to overflow, abort the VM.
*
* We have to leave the "reserved" area open until the "catch" handler has
* finished doing its processing. This is because the catch handler may
* need to resolve classes, which requires calling into the class loader if
* the classes aren't already in the "initiating loader" list.
*/
void dvmHandleStackOverflow(Thread* self, const Method* method)
{
/*
* Can we make the reserved area available?
*/
if (self->stackOverflowed) {
/*
* Already did, nothing to do but bail.
*/
ALOGE("DalvikVM: double-overflow of stack in threadid=%d; aborting",
self->threadId);
dvmDumpThread(self, false);
dvmAbort();
}
/* open it up to the full range */
ALOGI("threadid=%d: stack overflow on call to %s.%s:%s",
self->threadId,
method->clazz->descriptor, method->name, method->shorty);
StackSaveArea* saveArea = SAVEAREA_FROM_FP(self->interpSave.curFrame);
ALOGI(" method requires %d+%d+%d=%d bytes, fp is %p (%d left)",
method->registersSize * 4, sizeof(StackSaveArea), method->outsSize * 4,
(method->registersSize + method->outsSize) * 4 + sizeof(StackSaveArea),
saveArea, (u1*) saveArea - self->interpStackEnd);
ALOGI(" expanding stack end (%p to %p)", self->interpStackEnd,
self->interpStackStart - self->interpStackSize);
//dvmDumpThread(self, false);
self->interpStackEnd = self->interpStackStart - self->interpStackSize;
self->stackOverflowed = true;
/*
* If we were trying to throw an exception when the stack overflowed,
* we will blow up when doing the class lookup on StackOverflowError
* because of the pending exception. So, we clear it and make it
* the cause of the SOE.
*/
Object* excep = dvmGetException(self);
if (excep != NULL) {
ALOGW("Stack overflow while throwing exception");
dvmClearException(self);
}
dvmThrowChainedException(gDvm.exStackOverflowError, NULL, excep);
}
/*
* Initialize an exception with an appropriate constructor.
*
* "exception" is the exception object to initialize.
* Either or both of "msg" and "cause" may be null.
* "self" is dvmThreadSelf(), passed in so we don't have to look it up again.
*
* If the process of initializing the exception causes another
* exception (e.g., OutOfMemoryError) to be thrown, return an error
* and leave self->exception intact.
*/
static bool initException(Object* exception, const char* msg, Object* cause,
Thread* self)
{
enum {
kInitUnknown,
kInitNoarg,
kInitMsg,
kInitMsgThrow,
kInitThrow
} initKind = kInitUnknown;
Method* initMethod = NULL;
ClassObject* excepClass = exception->clazz;
StringObject* msgStr = NULL;
bool result = false;
bool needInitCause = false;
assert(self != NULL);
assert(self->exception == NULL);
/* if we have a message, create a String */
if (msg == NULL)
msgStr = NULL;
else {
msgStr = dvmCreateStringFromCstr(msg);
if (msgStr == NULL) {
LOGW("Could not allocate message string \"%s\" while "
"throwing internal exception (%s)\n",
msg, excepClass->descriptor);
goto bail;
}
}
if (cause != NULL) {
if (!dvmInstanceof(cause->clazz, gDvm.classJavaLangThrowable)) {
LOGE("Tried to init exception with cause '%s'\n",
cause->clazz->descriptor);
dvmAbort();
}
}
/*
* The Throwable class has four public constructors:
* (1) Throwable()
* (2) Throwable(String message)
* (3) Throwable(String message, Throwable cause) (added in 1.4)
* (4) Throwable(Throwable cause) (added in 1.4)
*
* The first two are part of the original design, and most exception
* classes should support them. The third prototype was used by
* individual exceptions. e.g. ClassNotFoundException added it in 1.2.
* The general "cause" mechanism was added in 1.4. Some classes,
* such as IllegalArgumentException, initially supported the first
* two, but added the second two in a later release.
*
* Exceptions may be picky about how their "cause" field is initialized.
* If you call ClassNotFoundException(String), it may choose to
* initialize its "cause" field to null. Doing so prevents future
* calls to Throwable.initCause().
*
* So, if "cause" is not NULL, we need to look for a constructor that
* takes a throwable. If we can't find one, we fall back on calling
* #1/#2 and making a separate call to initCause(). Passing a null ref
* for "message" into Throwable(String, Throwable) is allowed, but we
* prefer to use the Throwable-only version because it has different
* behavior.
*
* java.lang.TypeNotPresentException is a strange case -- it has #3 but
* not #2. (Some might argue that the constructor is actually not #3,
* because it doesn't take the message string as an argument, but it
* has the same effect and we can work with it here.)
*
* java.lang.AssertionError is also a strange case -- it has a
* constructor that takes an Object, but not one that takes a String.
* There may be other cases like this, as well, so we generally look
* for an Object-taking constructor if we can't find one that takes
* a String.
*/
if (cause == NULL) {
if (msgStr == NULL) {
initMethod = findExceptionInitMethod(excepClass, false, false);
initKind = kInitNoarg;
} else {
initMethod = findExceptionInitMethod(excepClass, true, false);
if (initMethod != NULL) {
initKind = kInitMsg;
} else {
/* no #2, try #3 */
initMethod = findExceptionInitMethod(excepClass, true, true);
if (initMethod != NULL) {
initKind = kInitMsgThrow;
}
}
}
} else {
if (msgStr == NULL) {
initMethod = findExceptionInitMethod(excepClass, false, true);
if (initMethod != NULL) {
initKind = kInitThrow;
} else {
initMethod = findExceptionInitMethod(excepClass, false, false);
initKind = kInitNoarg;
needInitCause = true;
}
} else {
initMethod = findExceptionInitMethod(excepClass, true, true);
if (initMethod != NULL) {
initKind = kInitMsgThrow;
} else {
initMethod = findExceptionInitMethod(excepClass, true, false);
initKind = kInitMsg;
needInitCause = true;
}
}
}
if (initMethod == NULL) {
/*
* We can't find the desired constructor. This can happen if a
* subclass of java/lang/Throwable doesn't define an expected
* constructor, e.g. it doesn't provide one that takes a string
* when a message has been provided.
*/
LOGW("WARNING: exception class '%s' missing constructor "
"(msg='%s' kind=%d)\n",
excepClass->descriptor, msg, initKind);
assert(strcmp(excepClass->descriptor,
"Ljava/lang/RuntimeException;") != 0);
dvmThrowChainedException("Ljava/lang/RuntimeException;",
"re-throw on exception class missing constructor", NULL);
goto bail;
}
/*
* Call the constructor with the appropriate arguments.
*/
JValue unused;
switch (initKind) {
case kInitNoarg:
LOGVV("+++ exc noarg (ic=%d)\n", needInitCause);
dvmCallMethod(self, initMethod, exception, &unused);
break;
case kInitMsg:
LOGVV("+++ exc msg (ic=%d)\n", needInitCause);
dvmCallMethod(self, initMethod, exception, &unused, msgStr);
break;
case kInitThrow:
LOGVV("+++ exc throw");
assert(!needInitCause);
dvmCallMethod(self, initMethod, exception, &unused, cause);
break;
case kInitMsgThrow:
LOGVV("+++ exc msg+throw");
assert(!needInitCause);
dvmCallMethod(self, initMethod, exception, &unused, msgStr, cause);
break;
default:
assert(false);
goto bail;
}
/*
* It's possible the constructor has thrown an exception. If so, we
* return an error and let our caller deal with it.
*/
if (self->exception != NULL) {
LOGW("Exception thrown (%s) while throwing internal exception (%s)\n",
self->exception->clazz->descriptor, exception->clazz->descriptor);
goto bail;
}
/*
* If this exception was caused by another exception, and we weren't
* able to find a cause-setting constructor, set the "cause" field
* with an explicit call.
*/
if (needInitCause) {
Method* initCause;
initCause = dvmFindVirtualMethodHierByDescriptor(excepClass, "initCause",
"(Ljava/lang/Throwable;)Ljava/lang/Throwable;");
if (initCause != NULL) {
dvmCallMethod(self, initCause, exception, &unused, cause);
if (self->exception != NULL) {
/* initCause() threw an exception; return an error and
* let the caller deal with it.
*/
LOGW("Exception thrown (%s) during initCause() "
"of internal exception (%s)\n",
self->exception->clazz->descriptor,
exception->clazz->descriptor);
goto bail;
}
} else {
LOGW("WARNING: couldn't find initCause in '%s'\n",
excepClass->descriptor);
}
}
result = true;
bail:
dvmReleaseTrackedAlloc((Object*) msgStr, self); // NULL is ok
return result;
}
/*
* Start/continue throwing process now that we have a class reference.
*/
void dvmThrowChainedExceptionByClass(ClassObject* excepClass, const char* msg,
Object* cause)
{
Thread* self = dvmThreadSelf();
Object* exception;
/* make sure the exception is initialized */
if (!dvmIsClassInitialized(excepClass) && !dvmInitClass(excepClass)) {
LOGE("ERROR: unable to initialize exception class '%s'\n",
excepClass->descriptor);
if (strcmp(excepClass->descriptor, "Ljava/lang/InternalError;") == 0)
dvmAbort();
dvmThrowChainedException("Ljava/lang/InternalError;",
"failed to init original exception class", cause);
return;
}
exception = dvmAllocObject(excepClass, ALLOC_DEFAULT);
if (exception == NULL) {
/*
* We're in a lot of trouble. We might be in the process of
* throwing an out-of-memory exception, in which case the
* pre-allocated object will have been thrown when our object alloc
* failed. So long as there's an exception raised, return and
* allow the system to try to recover. If not, something is broken
* and we need to bail out.
*/
if (dvmCheckException(self))
goto bail;
LOGE("FATAL: unable to allocate exception '%s' '%s'\n",
excepClass->descriptor, msg != NULL ? msg : "(no msg)");
dvmAbort();
}
/*
* Init the exception.
*/
if (gDvm.optimizing) {
/* need the exception object, but can't invoke interpreted code */
LOGV("Skipping init of exception %s '%s'\n",
excepClass->descriptor, msg);
} else {
assert(excepClass == exception->clazz);
if (!initException(exception, msg, cause, self)) {
/*
* Whoops. If we can't initialize the exception, we can't use
* it. If there's an exception already set, the constructor
* probably threw an OutOfMemoryError.
*/
if (!dvmCheckException(self)) {
/*
* We're required to throw something, so we just
* throw the pre-constructed internal error.
*/
self->exception = gDvm.internalErrorObj;
}
goto bail;
}
}
self->exception = exception;
bail:
dvmReleaseTrackedAlloc(exception, self);
}
