gecko/dom/plugins/base/nsJSNPRuntime.cpp
Luke Wagner ce71e55555 Bug 625199 - s/JSAutoEnterCompartment/JSAutoCompartment/ and make it infallible (r=bholley)
--HG--
extra : rebase_source : 12acf2288285f5caefd7fecea8207de3a47eab5b
2012-08-21 18:42:53 -07:00

2324 lines
60 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "base/basictypes.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "jswrapper.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsJSNPRuntime.h"
#include "nsNPAPIPlugin.h"
#include "nsNPAPIPluginInstance.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptContext.h"
#include "nsDOMJSUtils.h"
#include "nsIDocument.h"
#include "nsIJSRuntimeService.h"
#include "nsIJSContextStack.h"
#include "nsIXPConnect.h"
#include "nsIDOMElement.h"
#include "prmem.h"
#include "nsIContent.h"
#include "nsIPluginInstanceOwner.h"
#include "mozilla/HashFunctions.h"
#define NPRUNTIME_JSCLASS_NAME "NPObject JS wrapper class"
using namespace mozilla::plugins::parent;
using namespace mozilla;
#include "mozilla/plugins/PluginScriptableObjectParent.h"
using mozilla::plugins::PluginScriptableObjectParent;
using mozilla::plugins::ParentNPObject;
// Hash of JSObject wrappers that wraps JSObjects as NPObjects. There
// will be one wrapper per JSObject per plugin instance, i.e. if two
// plugins access the JSObject x, two wrappers for x will be
// created. This is needed to be able to properly drop the wrappers
// when a plugin is torn down in case there's a leak in the plugin (we
// don't want to leak the world just because a plugin leaks an
// NPObject).
static PLDHashTable sJSObjWrappers;
// Hash of NPObject wrappers that wrap NPObjects as JSObjects.
static PLDHashTable sNPObjWrappers;
// Global wrapper count. This includes JSObject wrappers *and*
// NPObject wrappers. When this count goes to zero, there are no more
// wrappers and we can kill off hash tables etc.
static int32_t sWrapperCount;
// The JSRuntime. Used to unroot JSObjects when no JSContext is
// reachable.
static JSRuntime *sJSRuntime;
// The JS context stack, we use this to push a plugin's JSContext onto
// while executing JS on the context.
static nsIJSContextStack *sContextStack;
static nsTArray<NPObject*>* sDelayedReleases;
namespace {
inline bool
NPObjectIsOutOfProcessProxy(NPObject *obj)
{
return obj->_class == PluginScriptableObjectParent::GetClass();
}
} // anonymous namespace
// Helper class that reports any JS exceptions that were thrown while
// the plugin executed JS.
class AutoJSExceptionReporter
{
public:
AutoJSExceptionReporter(JSContext *cx)
: mCx(cx)
{
}
~AutoJSExceptionReporter()
{
JS_ReportPendingException(mCx);
}
protected:
JSContext *mCx;
};
NPClass nsJSObjWrapper::sJSObjWrapperNPClass =
{
NP_CLASS_STRUCT_VERSION,
nsJSObjWrapper::NP_Allocate,
nsJSObjWrapper::NP_Deallocate,
nsJSObjWrapper::NP_Invalidate,
nsJSObjWrapper::NP_HasMethod,
nsJSObjWrapper::NP_Invoke,
nsJSObjWrapper::NP_InvokeDefault,
nsJSObjWrapper::NP_HasProperty,
nsJSObjWrapper::NP_GetProperty,
nsJSObjWrapper::NP_SetProperty,
nsJSObjWrapper::NP_RemoveProperty,
nsJSObjWrapper::NP_Enumerate,
nsJSObjWrapper::NP_Construct
};
static JSBool
NPObjWrapper_AddProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp);
static JSBool
NPObjWrapper_DelProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp);
static JSBool
NPObjWrapper_SetProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSBool strict,
JSMutableHandleValue vp);
static JSBool
NPObjWrapper_GetProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp);
static JSBool
NPObjWrapper_newEnumerate(JSContext *cx, JSHandleObject obj, JSIterateOp enum_op,
jsval *statep, jsid *idp);
static JSBool
NPObjWrapper_NewResolve(JSContext *cx, JSHandleObject obj, JSHandleId id, unsigned flags,
JSMutableHandleObject objp);
static JSBool
NPObjWrapper_Convert(JSContext *cx, JSHandleObject obj, JSType type, JSMutableHandleValue vp);
static void
NPObjWrapper_Finalize(JSFreeOp *fop, JSObject *obj);
static JSBool
NPObjWrapper_Call(JSContext *cx, unsigned argc, jsval *vp);
static JSBool
NPObjWrapper_Construct(JSContext *cx, unsigned argc, jsval *vp);
static JSBool
CreateNPObjectMember(NPP npp, JSContext *cx, JSObject *obj, NPObject *npobj,
jsid id, NPVariant* getPropertyResult, jsval *vp);
static JSClass sNPObjectJSWrapperClass =
{
NPRUNTIME_JSCLASS_NAME,
JSCLASS_HAS_PRIVATE | JSCLASS_IMPLEMENTS_BARRIERS | JSCLASS_NEW_RESOLVE | JSCLASS_NEW_ENUMERATE,
NPObjWrapper_AddProperty,
NPObjWrapper_DelProperty,
NPObjWrapper_GetProperty,
NPObjWrapper_SetProperty,
(JSEnumerateOp)NPObjWrapper_newEnumerate,
(JSResolveOp)NPObjWrapper_NewResolve,
NPObjWrapper_Convert,
NPObjWrapper_Finalize,
nullptr, /* checkAccess */
NPObjWrapper_Call,
nullptr, /* hasInstance */
NPObjWrapper_Construct
};
typedef struct NPObjectMemberPrivate {
JSObject *npobjWrapper;
jsval fieldValue;
NPIdentifier methodName;
NPP npp;
} NPObjectMemberPrivate;
static JSBool
NPObjectMember_Convert(JSContext *cx, JSHandleObject obj, JSType type, JSMutableHandleValue vp);
static void
NPObjectMember_Finalize(JSFreeOp *fop, JSObject *obj);
static JSBool
NPObjectMember_Call(JSContext *cx, unsigned argc, jsval *vp);
static void
NPObjectMember_Trace(JSTracer *trc, JSObject *obj);
static JSClass sNPObjectMemberClass =
{
"NPObject Ambiguous Member class", JSCLASS_HAS_PRIVATE | JSCLASS_IMPLEMENTS_BARRIERS,
JS_PropertyStub, JS_PropertyStub,
JS_PropertyStub, JS_StrictPropertyStub, JS_EnumerateStub,
JS_ResolveStub, NPObjectMember_Convert,
NPObjectMember_Finalize, nullptr, NPObjectMember_Call,
nullptr, nullptr, NPObjectMember_Trace
};
static void
OnWrapperDestroyed();
static void
DelayedReleaseGCCallback(JSRuntime* rt, JSGCStatus status)
{
if (JSGC_END == status) {
// Take ownership of sDelayedReleases and null it out now. The
// _releaseobject call below can reenter GC and double-free these objects.
nsAutoPtr<nsTArray<NPObject*> > delayedReleases(sDelayedReleases);
sDelayedReleases = nullptr;
if (delayedReleases) {
for (uint32_t i = 0; i < delayedReleases->Length(); ++i) {
NPObject* obj = (*delayedReleases)[i];
if (obj)
_releaseobject(obj);
OnWrapperDestroyed();
}
}
}
}
static void
OnWrapperCreated()
{
if (sWrapperCount++ == 0) {
static const char rtsvc_id[] = "@mozilla.org/js/xpc/RuntimeService;1";
nsCOMPtr<nsIJSRuntimeService> rtsvc(do_GetService(rtsvc_id));
if (!rtsvc)
return;
rtsvc->GetRuntime(&sJSRuntime);
NS_ASSERTION(sJSRuntime != nullptr, "no JSRuntime?!");
// Register our GC callback to perform delayed destruction of finalized
// NPObjects. Leave this callback around and don't ever unregister it.
rtsvc->RegisterGCCallback(DelayedReleaseGCCallback);
CallGetService("@mozilla.org/js/xpc/ContextStack;1", &sContextStack);
}
}
static void
OnWrapperDestroyed()
{
NS_ASSERTION(sWrapperCount, "Whaaa, unbalanced created/destroyed calls!");
if (--sWrapperCount == 0) {
if (sJSObjWrappers.ops) {
NS_ASSERTION(sJSObjWrappers.entryCount == 0, "Uh, hash not empty?");
// No more wrappers, and our hash was initialized. Finish the
// hash to prevent leaking it.
PL_DHashTableFinish(&sJSObjWrappers);
sJSObjWrappers.ops = nullptr;
}
if (sNPObjWrappers.ops) {
NS_ASSERTION(sNPObjWrappers.entryCount == 0, "Uh, hash not empty?");
// No more wrappers, and our hash was initialized. Finish the
// hash to prevent leaking it.
PL_DHashTableFinish(&sNPObjWrappers);
sNPObjWrappers.ops = nullptr;
}
// No more need for this.
sJSRuntime = nullptr;
NS_IF_RELEASE(sContextStack);
}
}
struct AutoCXPusher
{
AutoCXPusher(JSContext *cx)
{
// Precondition explaining why we don't need to worry about errors
// in OnWrapperCreated.
NS_PRECONDITION(sWrapperCount > 0,
"must have live wrappers when using AutoCXPusher");
// Call OnWrapperCreated and OnWrapperDestroyed to ensure that the
// last OnWrapperDestroyed doesn't happen while we're on the stack
// and null out sContextStack.
OnWrapperCreated();
sContextStack->Push(cx);
}
~AutoCXPusher()
{
JSContext *cx = nullptr;
sContextStack->Pop(&cx);
JSContext *currentCx = nullptr;
sContextStack->Peek(&currentCx);
if (!currentCx) {
// No JS is running, tell the context we're done executing
// script.
nsIScriptContext *scx = GetScriptContextFromJSContext(cx);
if (scx) {
scx->ScriptEvaluated(true);
}
}
OnWrapperDestroyed();
}
};
namespace mozilla {
namespace plugins {
namespace parent {
JSContext *
GetJSContext(NPP npp)
{
NS_ENSURE_TRUE(npp, nullptr);
nsNPAPIPluginInstance *inst = (nsNPAPIPluginInstance *)npp->ndata;
NS_ENSURE_TRUE(inst, nullptr);
nsCOMPtr<nsIPluginInstanceOwner> owner;
inst->GetOwner(getter_AddRefs(owner));
NS_ENSURE_TRUE(owner, nullptr);
nsCOMPtr<nsIDocument> doc;
owner->GetDocument(getter_AddRefs(doc));
NS_ENSURE_TRUE(doc, nullptr);
nsCOMPtr<nsISupports> documentContainer = doc->GetContainer();
nsCOMPtr<nsIScriptGlobalObject> sgo(do_GetInterface(documentContainer));
NS_ENSURE_TRUE(sgo, nullptr);
nsIScriptContext *scx = sgo->GetContext();
NS_ENSURE_TRUE(scx, nullptr);
return scx->GetNativeContext();
}
}
}
}
static NPP
LookupNPP(NPObject *npobj);
static jsval
NPVariantToJSVal(NPP npp, JSContext *cx, const NPVariant *variant)
{
switch (variant->type) {
case NPVariantType_Void :
return JSVAL_VOID;
case NPVariantType_Null :
return JSVAL_NULL;
case NPVariantType_Bool :
return BOOLEAN_TO_JSVAL(NPVARIANT_TO_BOOLEAN(*variant));
case NPVariantType_Int32 :
{
// Don't use INT_TO_JSVAL directly to prevent bugs when dealing
// with ints larger than what fits in a integer jsval.
return ::JS_NumberValue(NPVARIANT_TO_INT32(*variant));
}
case NPVariantType_Double :
{
return ::JS_NumberValue(NPVARIANT_TO_DOUBLE(*variant));
}
case NPVariantType_String :
{
const NPString *s = &NPVARIANT_TO_STRING(*variant);
NS_ConvertUTF8toUTF16 utf16String(s->UTF8Characters, s->UTF8Length);
JSString *str =
::JS_NewUCStringCopyN(cx, reinterpret_cast<const jschar*>
(utf16String.get()),
utf16String.Length());
if (str) {
return STRING_TO_JSVAL(str);
}
break;
}
case NPVariantType_Object:
{
if (npp) {
JSObject *obj =
nsNPObjWrapper::GetNewOrUsed(npp, cx, NPVARIANT_TO_OBJECT(*variant));
if (obj) {
return OBJECT_TO_JSVAL(obj);
}
}
NS_ERROR("Error wrapping NPObject!");
break;
}
default:
NS_ERROR("Unknown NPVariant type!");
}
NS_ERROR("Unable to convert NPVariant to jsval!");
return JSVAL_VOID;
}
bool
JSValToNPVariant(NPP npp, JSContext *cx, jsval val, NPVariant *variant)
{
NS_ASSERTION(npp, "Must have an NPP to wrap a jsval!");
if (JSVAL_IS_PRIMITIVE(val)) {
if (val == JSVAL_VOID) {
VOID_TO_NPVARIANT(*variant);
} else if (JSVAL_IS_NULL(val)) {
NULL_TO_NPVARIANT(*variant);
} else if (JSVAL_IS_BOOLEAN(val)) {
BOOLEAN_TO_NPVARIANT(JSVAL_TO_BOOLEAN(val), *variant);
} else if (JSVAL_IS_INT(val)) {
INT32_TO_NPVARIANT(JSVAL_TO_INT(val), *variant);
} else if (JSVAL_IS_DOUBLE(val)) {
double d = JSVAL_TO_DOUBLE(val);
int i;
if (JS_DoubleIsInt32(d, &i)) {
INT32_TO_NPVARIANT(i, *variant);
} else {
DOUBLE_TO_NPVARIANT(d, *variant);
}
} else if (JSVAL_IS_STRING(val)) {
JSString *jsstr = JSVAL_TO_STRING(val);
size_t length;
const jschar *chars = ::JS_GetStringCharsZAndLength(cx, jsstr, &length);
if (!chars) {
return false;
}
nsDependentString str(chars, length);
uint32_t len;
char *p = ToNewUTF8String(str, &len);
if (!p) {
return false;
}
STRINGN_TO_NPVARIANT(p, len, *variant);
} else {
NS_ERROR("Unknown primitive type!");
return false;
}
return true;
}
// The reflected plugin object may be in another compartment if the plugin
// element has since been adopted into a new document. We don't bother
// transplanting the plugin objects, and just do a unwrap with security
// checks if we encounter one of them as an argument. If the unwrap fails,
// we clear the pending exception and just run with the original wrapped object,
// since sometimes there are legitimate cases where a security wrapper ends
// up here (for example, Location objects, which are _always_ behind security
// wrappers).
//
// NB: In addition to clearing the pending exception, we also have to temporarily
// disable the error reporter, because SpiderMonkey calls it directly if there's
// no JS code on the stack, which might be the case here.
JSObject *obj = JSVAL_TO_OBJECT(val);
JSErrorReporter reporter = JS_SetErrorReporter(cx, NULL);
obj = js::UnwrapObjectChecked(cx, obj);
JS_SetErrorReporter(cx, reporter);
if (!obj) {
JS_ClearPendingException(cx);
obj = JSVAL_TO_OBJECT(val);
}
NPObject *npobj = nsJSObjWrapper::GetNewOrUsed(npp, cx, obj);
if (!npobj) {
return false;
}
// Pass over ownership of npobj to *variant
OBJECT_TO_NPVARIANT(npobj, *variant);
return true;
}
static void
ThrowJSException(JSContext *cx, const char *message)
{
const char *ex = PeekException();
if (ex) {
nsAutoString ucex;
if (message) {
AppendASCIItoUTF16(message, ucex);
AppendASCIItoUTF16(" [plugin exception: ", ucex);
}
AppendUTF8toUTF16(ex, ucex);
if (message) {
AppendASCIItoUTF16("].", ucex);
}
JSString *str = ::JS_NewUCStringCopyN(cx, (jschar *)ucex.get(),
ucex.Length());
if (str) {
::JS_SetPendingException(cx, STRING_TO_JSVAL(str));
}
PopException();
} else {
::JS_ReportError(cx, message);
}
}
static JSBool
ReportExceptionIfPending(JSContext *cx)
{
const char *ex = PeekException();
if (!ex) {
return JS_TRUE;
}
ThrowJSException(cx, nullptr);
return JS_FALSE;
}
nsJSObjWrapper::nsJSObjWrapper(NPP npp)
: nsJSObjWrapperKey(nullptr, npp)
{
MOZ_COUNT_CTOR(nsJSObjWrapper);
OnWrapperCreated();
}
nsJSObjWrapper::~nsJSObjWrapper()
{
MOZ_COUNT_DTOR(nsJSObjWrapper);
// Invalidate first, since it relies on sJSRuntime and sJSObjWrappers.
NP_Invalidate(this);
OnWrapperDestroyed();
}
// static
NPObject *
nsJSObjWrapper::NP_Allocate(NPP npp, NPClass *aClass)
{
NS_ASSERTION(aClass == &sJSObjWrapperNPClass,
"Huh, wrong class passed to NP_Allocate()!!!");
return new nsJSObjWrapper(npp);
}
// static
void
nsJSObjWrapper::NP_Deallocate(NPObject *npobj)
{
// nsJSObjWrapper::~nsJSObjWrapper() will call NP_Invalidate().
delete (nsJSObjWrapper *)npobj;
}
// static
void
nsJSObjWrapper::NP_Invalidate(NPObject *npobj)
{
nsJSObjWrapper *jsnpobj = (nsJSObjWrapper *)npobj;
if (jsnpobj && jsnpobj->mJSObj) {
// Unroot the object's JSObject
js_RemoveRoot(sJSRuntime, &jsnpobj->mJSObj);
if (sJSObjWrappers.ops) {
// Remove the wrapper from the hash
nsJSObjWrapperKey key(jsnpobj->mJSObj, jsnpobj->mNpp);
PL_DHashTableOperate(&sJSObjWrappers, &key, PL_DHASH_REMOVE);
}
// Forget our reference to the JSObject.
jsnpobj->mJSObj = nullptr;
}
}
static JSBool
GetProperty(JSContext *cx, JSObject *obj, NPIdentifier id, jsval *rval)
{
NS_ASSERTION(NPIdentifierIsInt(id) || NPIdentifierIsString(id),
"id must be either string or int!\n");
return ::JS_GetPropertyById(cx, obj, NPIdentifierToJSId(id), rval);
}
// static
bool
nsJSObjWrapper::NP_HasMethod(NPObject *npobj, NPIdentifier id)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_HasMethod!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
AutoJSExceptionReporter reporter(cx);
jsval v;
JSBool ok = GetProperty(cx, npjsobj->mJSObj, id, &v);
return ok && !JSVAL_IS_PRIMITIVE(v) &&
::JS_ObjectIsFunction(cx, JSVAL_TO_OBJECT(v));
}
static bool
doInvoke(NPObject *npobj, NPIdentifier method, const NPVariant *args,
uint32_t argCount, bool ctorCall, NPVariant *result)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj || !result) {
ThrowJSException(cx, "Null npobj, or result in doInvoke!");
return false;
}
// Initialize *result
VOID_TO_NPVARIANT(*result);
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
jsval fv;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
AutoJSExceptionReporter reporter(cx);
if (method != NPIdentifier_VOID) {
if (!GetProperty(cx, npjsobj->mJSObj, method, &fv) ||
::JS_TypeOfValue(cx, fv) != JSTYPE_FUNCTION) {
return false;
}
} else {
fv = OBJECT_TO_JSVAL(npjsobj->mJSObj);
}
jsval jsargs_buf[8];
jsval *jsargs = jsargs_buf;
if (argCount > (sizeof(jsargs_buf) / sizeof(jsval))) {
// Our stack buffer isn't large enough to hold all arguments,
// malloc a buffer.
jsargs = (jsval *)PR_Malloc(argCount * sizeof(jsval));
if (!jsargs) {
::JS_ReportOutOfMemory(cx);
return false;
}
}
jsval v;
JSBool ok;
{
JS::AutoArrayRooter tvr(cx, 0, jsargs);
// Convert args
for (uint32_t i = 0; i < argCount; ++i) {
jsargs[i] = NPVariantToJSVal(npp, cx, args + i);
tvr.changeLength(i + 1);
}
if (ctorCall) {
JSObject *newObj =
::JS_New(cx, npjsobj->mJSObj, argCount, jsargs);
if (newObj) {
v = OBJECT_TO_JSVAL(newObj);
ok = JS_TRUE;
} else {
ok = JS_FALSE;
}
} else {
ok = ::JS_CallFunctionValue(cx, npjsobj->mJSObj, fv, argCount, jsargs, &v);
}
}
if (jsargs != jsargs_buf)
PR_Free(jsargs);
if (ok)
ok = JSValToNPVariant(npp, cx, v, result);
// return ok == JS_TRUE to quiet down compiler warning, even if
// return ok is what we really want.
return ok == JS_TRUE;
}
// static
bool
nsJSObjWrapper::NP_Invoke(NPObject *npobj, NPIdentifier method,
const NPVariant *args, uint32_t argCount,
NPVariant *result)
{
if (method == NPIdentifier_VOID) {
return false;
}
return doInvoke(npobj, method, args, argCount, false, result);
}
// static
bool
nsJSObjWrapper::NP_InvokeDefault(NPObject *npobj, const NPVariant *args,
uint32_t argCount, NPVariant *result)
{
return doInvoke(npobj, NPIdentifier_VOID, args, argCount, false,
result);
}
// static
bool
nsJSObjWrapper::NP_HasProperty(NPObject *npobj, NPIdentifier id)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_HasProperty!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
JSBool found, ok = JS_FALSE;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
AutoJSExceptionReporter reporter(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
NS_ASSERTION(NPIdentifierIsInt(id) || NPIdentifierIsString(id),
"id must be either string or int!\n");
ok = ::JS_HasPropertyById(cx, npjsobj->mJSObj, NPIdentifierToJSId(id), &found);
return ok && found;
}
// static
bool
nsJSObjWrapper::NP_GetProperty(NPObject *npobj, NPIdentifier id,
NPVariant *result)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_GetProperty!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
AutoJSExceptionReporter reporter(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
jsval v;
return (GetProperty(cx, npjsobj->mJSObj, id, &v) &&
JSValToNPVariant(npp, cx, v, result));
}
// static
bool
nsJSObjWrapper::NP_SetProperty(NPObject *npobj, NPIdentifier id,
const NPVariant *value)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_SetProperty!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
JSBool ok = JS_FALSE;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
AutoJSExceptionReporter reporter(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
jsval v = NPVariantToJSVal(npp, cx, value);
JS::AutoValueRooter tvr(cx, v);
NS_ASSERTION(NPIdentifierIsInt(id) || NPIdentifierIsString(id),
"id must be either string or int!\n");
ok = ::JS_SetPropertyById(cx, npjsobj->mJSObj, NPIdentifierToJSId(id), &v);
// return ok == JS_TRUE to quiet down compiler warning, even if
// return ok is what we really want.
return ok == JS_TRUE;
}
// static
bool
nsJSObjWrapper::NP_RemoveProperty(NPObject *npobj, NPIdentifier id)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_RemoveProperty!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
JSBool ok = JS_FALSE;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
AutoJSExceptionReporter reporter(cx);
jsval deleted = JSVAL_FALSE;
JSAutoCompartment ac(cx, npjsobj->mJSObj);
NS_ASSERTION(NPIdentifierIsInt(id) || NPIdentifierIsString(id),
"id must be either string or int!\n");
ok = ::JS_DeletePropertyById2(cx, npjsobj->mJSObj, NPIdentifierToJSId(id), &deleted);
if (ok && deleted == JSVAL_TRUE) {
// FIXME: See bug 425823, we shouldn't need to do this, and once
// that bug is fixed we can remove this code.
JSBool hasProp;
ok = ::JS_HasPropertyById(cx, npjsobj->mJSObj, NPIdentifierToJSId(id), &hasProp);
if (ok && hasProp) {
// The property might have been deleted, but it got
// re-resolved, so no, it's not really deleted.
deleted = JSVAL_FALSE;
}
}
// return ok == JS_TRUE to quiet down compiler warning, even if
// return ok is what we really want.
return ok == JS_TRUE && deleted == JSVAL_TRUE;
}
//static
bool
nsJSObjWrapper::NP_Enumerate(NPObject *npobj, NPIdentifier **idarray,
uint32_t *count)
{
NPP npp = NPPStack::Peek();
JSContext *cx = GetJSContext(npp);
*idarray = 0;
*count = 0;
if (!cx) {
return false;
}
if (!npobj) {
ThrowJSException(cx,
"Null npobj in nsJSObjWrapper::NP_Enumerate!");
return false;
}
nsJSObjWrapper *npjsobj = (nsJSObjWrapper *)npobj;
AutoCXPusher pusher(cx);
JSAutoRequest ar(cx);
AutoJSExceptionReporter reporter(cx);
JSAutoCompartment ac(cx, npjsobj->mJSObj);
JS::AutoIdArray ida(cx, JS_Enumerate(cx, npjsobj->mJSObj));
if (!ida) {
return false;
}
*count = ida.length();
*idarray = (NPIdentifier *)PR_Malloc(*count * sizeof(NPIdentifier));
if (!*idarray) {
ThrowJSException(cx, "Memory allocation failed for NPIdentifier!");
return false;
}
for (uint32_t i = 0; i < *count; i++) {
jsval v;
if (!JS_IdToValue(cx, ida[i], &v)) {
PR_Free(*idarray);
return false;
}
NPIdentifier id;
if (JSVAL_IS_STRING(v)) {
JSString *str = JS_InternJSString(cx, JSVAL_TO_STRING(v));
if (!str) {
PR_Free(*idarray);
return false;
}
id = StringToNPIdentifier(cx, str);
} else {
NS_ASSERTION(JSVAL_IS_INT(v),
"The element in ida must be either string or int!\n");
id = IntToNPIdentifier(JSVAL_TO_INT(v));
}
(*idarray)[i] = id;
}
return true;
}
//static
bool
nsJSObjWrapper::NP_Construct(NPObject *npobj, const NPVariant *args,
uint32_t argCount, NPVariant *result)
{
return doInvoke(npobj, NPIdentifier_VOID, args, argCount, true, result);
}
class JSObjWrapperHashEntry : public PLDHashEntryHdr
{
public:
nsJSObjWrapper *mJSObjWrapper;
};
static PLDHashNumber
JSObjWrapperHash(PLDHashTable *table, const void *key)
{
const nsJSObjWrapperKey *e = static_cast<const nsJSObjWrapperKey *>(key);
return HashGeneric(e->mJSObj, e->mNpp);
}
static bool
JSObjWrapperHashMatchEntry(PLDHashTable *table, const PLDHashEntryHdr *entry,
const void *key)
{
const nsJSObjWrapperKey *objWrapperKey =
static_cast<const nsJSObjWrapperKey *>(key);
const JSObjWrapperHashEntry *e =
static_cast<const JSObjWrapperHashEntry *>(entry);
return (e->mJSObjWrapper->mJSObj == objWrapperKey->mJSObj &&
e->mJSObjWrapper->mNpp == objWrapperKey->mNpp);
}
// Look up or create an NPObject that wraps the JSObject obj.
// static
NPObject *
nsJSObjWrapper::GetNewOrUsed(NPP npp, JSContext *cx, JSObject *obj)
{
if (!npp) {
NS_ERROR("Null NPP passed to nsJSObjWrapper::GetNewOrUsed()!");
return nullptr;
}
if (!cx) {
cx = GetJSContext(npp);
if (!cx) {
NS_ERROR("Unable to find a JSContext in nsJSObjWrapper::GetNewOrUsed()!");
return nullptr;
}
}
// No need to enter the right compartment here as we only get the
// class and private from the JSObject, neither of which cares about
// compartments.
JSClass *clazz = JS_GetClass(obj);
if (clazz == &sNPObjectJSWrapperClass) {
// obj is one of our own, its private data is the NPObject we're
// looking for.
NPObject *npobj = (NPObject *)::JS_GetPrivate(obj);
// If the private is null, that means that the object has already been torn
// down, possible because the owning plugin was destroyed (there can be
// multiple plugins, so the fact that it was destroyed does not prevent one
// of its dead JS objects from being passed to another plugin). There's not
// much use in wrapping such a dead object, so we just return null, causing
// us to throw.
if (!npobj)
return nullptr;
if (LookupNPP(npobj) == npp)
return _retainobject(npobj);
}
if (!sJSObjWrappers.ops) {
// No hash yet (or any more), initialize it.
static PLDHashTableOps ops =
{
PL_DHashAllocTable,
PL_DHashFreeTable,
JSObjWrapperHash,
JSObjWrapperHashMatchEntry,
PL_DHashMoveEntryStub,
PL_DHashClearEntryStub,
PL_DHashFinalizeStub
};
if (!PL_DHashTableInit(&sJSObjWrappers, &ops, nullptr,
sizeof(JSObjWrapperHashEntry), 16)) {
NS_ERROR("Error initializing PLDHashTable!");
return nullptr;
}
}
nsJSObjWrapperKey key(obj, npp);
JSObjWrapperHashEntry *entry = static_cast<JSObjWrapperHashEntry *>
(PL_DHashTableOperate(&sJSObjWrappers, &key, PL_DHASH_ADD));
if (!entry) {
// Out of memory.
return nullptr;
}
if (PL_DHASH_ENTRY_IS_BUSY(entry) && entry->mJSObjWrapper) {
// Found a live nsJSObjWrapper, return it.
return _retainobject(entry->mJSObjWrapper);
}
// No existing nsJSObjWrapper, create one.
nsJSObjWrapper *wrapper =
(nsJSObjWrapper *)_createobject(npp, &sJSObjWrapperNPClass);
if (!wrapper) {
// OOM? Remove the stale entry from the hash.
PL_DHashTableRawRemove(&sJSObjWrappers, entry);
return nullptr;
}
wrapper->mJSObj = obj;
entry->mJSObjWrapper = wrapper;
NS_ASSERTION(wrapper->mNpp == npp, "nsJSObjWrapper::mNpp not initialized!");
JSAutoRequest ar(cx);
// Root the JSObject, its lifetime is now tied to that of the
// NPObject.
if (!::JS_AddNamedObjectRoot(cx, &wrapper->mJSObj, "nsJSObjWrapper::mJSObject")) {
NS_ERROR("Failed to root JSObject!");
_releaseobject(wrapper);
PL_DHashTableRawRemove(&sJSObjWrappers, entry);
return nullptr;
}
return wrapper;
}
// Climb the prototype chain, unwrapping as necessary until we find an NP object
// wrapper.
//
// Because this function unwraps, its return value must be wrapped for the cx
// compartment for callers that plan to hold onto the result or do anything
// substantial with it.
static JSObject *
GetNPObjectWrapper(JSContext *cx, JSObject *obj, bool wrapResult = true)
{
while (obj && (obj = js::UnwrapObjectChecked(cx, obj))) {
if (JS_GetClass(obj) == &sNPObjectJSWrapperClass) {
if (wrapResult && !JS_WrapObject(cx, &obj)) {
return NULL;
}
return obj;
}
obj = ::JS_GetPrototype(obj);
}
return NULL;
}
static NPObject *
GetNPObject(JSContext *cx, JSObject *obj)
{
obj = GetNPObjectWrapper(cx, obj, /* wrapResult = */ false);
if (!obj) {
return nullptr;
}
return (NPObject *)::JS_GetPrivate(obj);
}
// Does not actually add a property because this is always followed by a
// SetProperty call.
static JSBool
NPObjWrapper_AddProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class || !npobj->_class->hasProperty ||
!npobj->_class->hasMethod) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
if (NPObjectIsOutOfProcessProxy(npobj)) {
return JS_TRUE;
}
PluginDestructionGuard pdg(LookupNPP(npobj));
NPIdentifier identifier = JSIdToNPIdentifier(id);
JSBool hasProperty = npobj->_class->hasProperty(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (hasProperty)
return JS_TRUE;
// We must permit methods here since JS_DefineUCFunction() will add
// the function as a property
JSBool hasMethod = npobj->_class->hasMethod(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (!hasMethod) {
ThrowJSException(cx, "Trying to add unsupported property on NPObject!");
return JS_FALSE;
}
return JS_TRUE;
}
static JSBool
NPObjWrapper_DelProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class || !npobj->_class->hasProperty ||
!npobj->_class->removeProperty) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
PluginDestructionGuard pdg(LookupNPP(npobj));
NPIdentifier identifier = JSIdToNPIdentifier(id);
if (!NPObjectIsOutOfProcessProxy(npobj)) {
JSBool hasProperty = npobj->_class->hasProperty(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (!hasProperty)
return JS_TRUE;
}
if (!npobj->_class->removeProperty(npobj, identifier))
vp.set(JSVAL_FALSE);
return ReportExceptionIfPending(cx);
}
static JSBool
NPObjWrapper_SetProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSBool strict,
JSMutableHandleValue vp)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class || !npobj->_class->hasProperty ||
!npobj->_class->setProperty) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
// Find out what plugin (NPP) is the owner of the object we're
// manipulating, and make it own any JSObject wrappers created here.
NPP npp = LookupNPP(npobj);
if (!npp) {
ThrowJSException(cx, "No NPP found for NPObject!");
return JS_FALSE;
}
PluginDestructionGuard pdg(npp);
NPIdentifier identifier = JSIdToNPIdentifier(id);
if (!NPObjectIsOutOfProcessProxy(npobj)) {
JSBool hasProperty = npobj->_class->hasProperty(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (!hasProperty) {
ThrowJSException(cx, "Trying to set unsupported property on NPObject!");
return JS_FALSE;
}
}
NPVariant npv;
if (!JSValToNPVariant(npp, cx, vp, &npv)) {
ThrowJSException(cx, "Error converting jsval to NPVariant!");
return JS_FALSE;
}
JSBool ok = npobj->_class->setProperty(npobj, identifier, &npv);
_releasevariantvalue(&npv); // Release the variant
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (!ok) {
ThrowJSException(cx, "Error setting property on NPObject!");
return JS_FALSE;
}
return JS_TRUE;
}
static JSBool
NPObjWrapper_GetProperty(JSContext *cx, JSHandleObject obj, JSHandleId id, JSMutableHandleValue vp)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class || !npobj->_class->hasProperty ||
!npobj->_class->hasMethod || !npobj->_class->getProperty) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
// Find out what plugin (NPP) is the owner of the object we're
// manipulating, and make it own any JSObject wrappers created here.
NPP npp = LookupNPP(npobj);
if (!npp) {
ThrowJSException(cx, "No NPP found for NPObject!");
return JS_FALSE;
}
PluginDestructionGuard pdg(npp);
bool hasProperty, hasMethod;
NPVariant npv;
VOID_TO_NPVARIANT(npv);
NPIdentifier identifier = JSIdToNPIdentifier(id);
if (NPObjectIsOutOfProcessProxy(npobj)) {
PluginScriptableObjectParent* actor =
static_cast<ParentNPObject*>(npobj)->parent;
// actor may be null if the plugin crashed.
if (!actor)
return JS_FALSE;
JSBool success = actor->GetPropertyHelper(identifier, &hasProperty,
&hasMethod, &npv);
if (!ReportExceptionIfPending(cx)) {
if (success)
_releasevariantvalue(&npv);
return JS_FALSE;
}
if (success) {
// We return NPObject Member class here to support ambiguous members.
if (hasProperty && hasMethod)
return CreateNPObjectMember(npp, cx, obj, npobj, id, &npv, vp.address());
if (hasProperty) {
vp.set(NPVariantToJSVal(npp, cx, &npv));
_releasevariantvalue(&npv);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
}
}
return JS_TRUE;
}
hasProperty = npobj->_class->hasProperty(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
hasMethod = npobj->_class->hasMethod(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
// We return NPObject Member class here to support ambiguous members.
if (hasProperty && hasMethod)
return CreateNPObjectMember(npp, cx, obj, npobj, id, nullptr, vp.address());
if (hasProperty) {
if (npobj->_class->getProperty(npobj, identifier, &npv))
vp.set(NPVariantToJSVal(npp, cx, &npv));
_releasevariantvalue(&npv);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
}
return JS_TRUE;
}
static JSBool
CallNPMethodInternal(JSContext *cx, JSObject *obj, unsigned argc, jsval *argv,
jsval *rval, bool ctorCall)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
// Find out what plugin (NPP) is the owner of the object we're
// manipulating, and make it own any JSObject wrappers created here.
NPP npp = LookupNPP(npobj);
if (!npp) {
ThrowJSException(cx, "Error finding NPP for NPObject!");
return JS_FALSE;
}
PluginDestructionGuard pdg(npp);
NPVariant npargs_buf[8];
NPVariant *npargs = npargs_buf;
if (argc > (sizeof(npargs_buf) / sizeof(NPVariant))) {
// Our stack buffer isn't large enough to hold all arguments,
// malloc a buffer.
npargs = (NPVariant *)PR_Malloc(argc * sizeof(NPVariant));
if (!npargs) {
ThrowJSException(cx, "Out of memory!");
return JS_FALSE;
}
}
// Convert arguments
uint32_t i;
for (i = 0; i < argc; ++i) {
if (!JSValToNPVariant(npp, cx, argv[i], npargs + i)) {
ThrowJSException(cx, "Error converting jsvals to NPVariants!");
if (npargs != npargs_buf) {
PR_Free(npargs);
}
return JS_FALSE;
}
}
NPVariant v;
VOID_TO_NPVARIANT(v);
JSObject *funobj = JSVAL_TO_OBJECT(argv[-2]);
JSBool ok;
const char *msg = "Error calling method on NPObject!";
if (ctorCall) {
// construct a new NPObject based on the NPClass in npobj. Fail if
// no construct method is available.
if (NP_CLASS_STRUCT_VERSION_HAS_CTOR(npobj->_class) &&
npobj->_class->construct) {
ok = npobj->_class->construct(npobj, npargs, argc, &v);
} else {
ok = JS_FALSE;
msg = "Attempt to construct object from class with no constructor.";
}
} else if (funobj != obj) {
// A obj.function() style call is made, get the method name from
// the function object.
if (npobj->_class->invoke) {
JSFunction *fun = ::JS_GetObjectFunction(funobj);
JSString *name = ::JS_InternJSString(cx, ::JS_GetFunctionId(fun));
NPIdentifier id = StringToNPIdentifier(cx, name);
ok = npobj->_class->invoke(npobj, id, npargs, argc, &v);
} else {
ok = JS_FALSE;
msg = "Attempt to call a method on object with no invoke method.";
}
} else {
if (npobj->_class->invokeDefault) {
// obj is a callable object that is being called, no method name
// available then. Invoke the default method.
ok = npobj->_class->invokeDefault(npobj, npargs, argc, &v);
} else {
ok = JS_FALSE;
msg = "Attempt to call a default method on object with no "
"invokeDefault method.";
}
}
// Release arguments.
for (i = 0; i < argc; ++i) {
_releasevariantvalue(npargs + i);
}
if (npargs != npargs_buf) {
PR_Free(npargs);
}
if (!ok) {
// ReportExceptionIfPending returns a return value, which is JS_TRUE
// if no exception was thrown. In that case, throw our own.
if (ReportExceptionIfPending(cx))
ThrowJSException(cx, msg);
return JS_FALSE;
}
*rval = NPVariantToJSVal(npp, cx, &v);
// *rval now owns the value, release our reference.
_releasevariantvalue(&v);
return ReportExceptionIfPending(cx);
}
static JSBool
CallNPMethod(JSContext *cx, unsigned argc, jsval *vp)
{
JSObject *obj = JS_THIS_OBJECT(cx, vp);
if (!obj)
return JS_FALSE;
return CallNPMethodInternal(cx, obj, argc, JS_ARGV(cx, vp), vp, false);
}
struct NPObjectEnumerateState {
uint32_t index;
uint32_t length;
NPIdentifier *value;
};
static JSBool
NPObjWrapper_newEnumerate(JSContext *cx, JSHandleObject obj, JSIterateOp enum_op,
jsval *statep, jsid *idp)
{
NPObject *npobj = GetNPObject(cx, obj);
NPIdentifier *enum_value;
uint32_t length;
NPObjectEnumerateState *state;
if (!npobj || !npobj->_class) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
PluginDestructionGuard pdg(LookupNPP(npobj));
NS_ASSERTION(statep, "Must have a statep to enumerate!");
switch(enum_op) {
case JSENUMERATE_INIT:
case JSENUMERATE_INIT_ALL:
state = new NPObjectEnumerateState();
if (!state) {
ThrowJSException(cx, "Memory allocation failed for "
"NPObjectEnumerateState!");
return JS_FALSE;
}
if (!NP_CLASS_STRUCT_VERSION_HAS_ENUM(npobj->_class) ||
!npobj->_class->enumerate) {
enum_value = 0;
length = 0;
} else if (!npobj->_class->enumerate(npobj, &enum_value, &length)) {
delete state;
if (ReportExceptionIfPending(cx)) {
// ReportExceptionIfPending returns a return value, which is JS_TRUE
// if no exception was thrown. In that case, throw our own.
ThrowJSException(cx, "Error enumerating properties on scriptable "
"plugin object");
}
return JS_FALSE;
}
state->value = enum_value;
state->length = length;
state->index = 0;
*statep = PRIVATE_TO_JSVAL(state);
if (idp) {
*idp = INT_TO_JSID(length);
}
break;
case JSENUMERATE_NEXT:
state = (NPObjectEnumerateState *)JSVAL_TO_PRIVATE(*statep);
enum_value = state->value;
length = state->length;
if (state->index != length) {
*idp = NPIdentifierToJSId(enum_value[state->index++]);
return JS_TRUE;
}
// FALL THROUGH
case JSENUMERATE_DESTROY:
state = (NPObjectEnumerateState *)JSVAL_TO_PRIVATE(*statep);
if (state->value)
PR_Free(state->value);
delete state;
*statep = JSVAL_NULL;
break;
}
return JS_TRUE;
}
static JSBool
NPObjWrapper_NewResolve(JSContext *cx, JSHandleObject obj, JSHandleId id, unsigned flags,
JSMutableHandleObject objp)
{
NPObject *npobj = GetNPObject(cx, obj);
if (!npobj || !npobj->_class || !npobj->_class->hasProperty ||
!npobj->_class->hasMethod) {
ThrowJSException(cx, "Bad NPObject as private data!");
return JS_FALSE;
}
PluginDestructionGuard pdg(LookupNPP(npobj));
NPIdentifier identifier = JSIdToNPIdentifier(id);
bool hasProperty = npobj->_class->hasProperty(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (hasProperty) {
NS_ASSERTION(JSID_IS_STRING(id) || JSID_IS_INT(id),
"id must be either string or int!\n");
if (!::JS_DefinePropertyById(cx, obj, id, JSVAL_VOID, nullptr,
nullptr, JSPROP_ENUMERATE)) {
return JS_FALSE;
}
objp.set(obj);
return JS_TRUE;
}
bool hasMethod = npobj->_class->hasMethod(npobj, identifier);
if (!ReportExceptionIfPending(cx))
return JS_FALSE;
if (hasMethod) {
NS_ASSERTION(JSID_IS_STRING(id) || JSID_IS_INT(id),
"id must be either string or int!\n");
JSFunction *fnc = ::JS_DefineFunctionById(cx, obj, id, CallNPMethod, 0,
JSPROP_ENUMERATE);
objp.set(obj);
return fnc != nullptr;
}
// no property or method
return JS_TRUE;
}
static JSBool
NPObjWrapper_Convert(JSContext *cx, JSHandleObject obj, JSType hint, JSMutableHandleValue vp)
{
JS_ASSERT(hint == JSTYPE_NUMBER || hint == JSTYPE_STRING || hint == JSTYPE_VOID);
// Plugins do not simply use JS_ConvertStub, and the default [[DefaultValue]]
// behavior, because that behavior involves calling toString or valueOf on
// objects which weren't designed to accommodate this. Usually this wouldn't
// be a problem, because the absence of either property, or the presence of
// either property with a value that isn't callable, will cause that property
// to simply be ignored. But there is a problem in one specific case: Java,
// specifically java.lang.Integer. The Integer class has static valueOf
// methods, none of which are nullary, so the JS-reflected method will behave
// poorly when called with no arguments. We work around this problem by
// giving plugins a [[DefaultValue]] which uses only toString and not valueOf.
jsval v = JSVAL_VOID;
if (!JS_GetProperty(cx, obj, "toString", &v))
return false;
if (!JSVAL_IS_PRIMITIVE(v) && JS_ObjectIsCallable(cx, JSVAL_TO_OBJECT(v))) {
if (!JS_CallFunctionValue(cx, obj, v, 0, NULL, vp.address()))
return false;
if (JSVAL_IS_PRIMITIVE(vp))
return true;
}
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_CANT_CONVERT_TO,
JS_GetClass(obj)->name,
hint == JSTYPE_VOID
? "primitive type"
: hint == JSTYPE_NUMBER
? "number"
: "string");
return false;
}
static void
NPObjWrapper_Finalize(JSFreeOp *fop, JSObject *obj)
{
NPObject *npobj = (NPObject *)::JS_GetPrivate(obj);
if (npobj) {
if (sNPObjWrappers.ops) {
PL_DHashTableOperate(&sNPObjWrappers, npobj, PL_DHASH_REMOVE);
}
}
if (!sDelayedReleases)
sDelayedReleases = new nsTArray<NPObject*>;
sDelayedReleases->AppendElement(npobj);
}
static JSBool
NPObjWrapper_Call(JSContext *cx, unsigned argc, jsval *vp)
{
return CallNPMethodInternal(cx, JSVAL_TO_OBJECT(JS_CALLEE(cx, vp)), argc,
JS_ARGV(cx, vp), vp, false);
}
static JSBool
NPObjWrapper_Construct(JSContext *cx, unsigned argc, jsval *vp)
{
return CallNPMethodInternal(cx, JSVAL_TO_OBJECT(JS_CALLEE(cx, vp)), argc,
JS_ARGV(cx, vp), vp, true);
}
class NPObjWrapperHashEntry : public PLDHashEntryHdr
{
public:
NPObject *mNPObj; // Must be the first member for the PLDHash stubs to work
JSObject *mJSObj;
NPP mNpp;
};
// An NPObject is going away, make sure we null out the JS object's
// private data in case this is an NPObject that came from a plugin
// and it's destroyed prematurely.
// static
void
nsNPObjWrapper::OnDestroy(NPObject *npobj)
{
if (!npobj) {
return;
}
if (npobj->_class == &nsJSObjWrapper::sJSObjWrapperNPClass) {
// npobj is one of our own, no private data to clean up here.
return;
}
if (!sNPObjWrappers.ops) {
// No hash yet (or any more), no used wrappers available.
return;
}
NPObjWrapperHashEntry *entry = static_cast<NPObjWrapperHashEntry *>
(PL_DHashTableOperate(&sNPObjWrappers, npobj, PL_DHASH_LOOKUP));
if (PL_DHASH_ENTRY_IS_BUSY(entry) && entry->mJSObj) {
// Found a live NPObject wrapper, null out its JSObjects' private
// data.
::JS_SetPrivate(entry->mJSObj, nullptr);
// Remove the npobj from the hash now that it went away.
PL_DHashTableRawRemove(&sNPObjWrappers, entry);
// The finalize hook will call OnWrapperDestroyed().
}
}
// Look up or create a JSObject that wraps the NPObject npobj.
// static
JSObject *
nsNPObjWrapper::GetNewOrUsed(NPP npp, JSContext *cx, NPObject *npobj)
{
if (!npobj) {
NS_ERROR("Null NPObject passed to nsNPObjWrapper::GetNewOrUsed()!");
return nullptr;
}
if (npobj->_class == &nsJSObjWrapper::sJSObjWrapperNPClass) {
// npobj is one of our own, return its existing JSObject.
JSObject *obj = ((nsJSObjWrapper *)npobj)->mJSObj;
if (!JS_WrapObject(cx, &obj)) {
return NULL;
}
return obj;
}
if (!npp) {
NS_ERROR("No npp passed to nsNPObjWrapper::GetNewOrUsed()!");
return nullptr;
}
if (!sNPObjWrappers.ops) {
// No hash yet (or any more), initialize it.
if (!PL_DHashTableInit(&sNPObjWrappers, PL_DHashGetStubOps(), nullptr,
sizeof(NPObjWrapperHashEntry), 16)) {
NS_ERROR("Error initializing PLDHashTable!");
return nullptr;
}
}
NPObjWrapperHashEntry *entry = static_cast<NPObjWrapperHashEntry *>
(PL_DHashTableOperate(&sNPObjWrappers, npobj, PL_DHASH_ADD));
if (!entry) {
// Out of memory
JS_ReportOutOfMemory(cx);
return nullptr;
}
if (PL_DHASH_ENTRY_IS_BUSY(entry) && entry->mJSObj) {
// Found a live NPObject wrapper. It may not be in the same compartment
// as cx, so we need to wrap it before returning it.
JSObject *obj = entry->mJSObj;
if (!JS_WrapObject(cx, &obj)) {
return NULL;
}
return obj;
}
entry->mNPObj = npobj;
entry->mNpp = npp;
JSAutoRequest ar(cx);
uint32_t generation = sNPObjWrappers.generation;
// No existing JSObject, create one.
JSObject *obj = ::JS_NewObject(cx, &sNPObjectJSWrapperClass, nullptr, nullptr);
if (generation != sNPObjWrappers.generation) {
// Reload entry if the JS_NewObject call caused a GC and reallocated
// the table (see bug 445229). This is guaranteed to succeed.
entry = static_cast<NPObjWrapperHashEntry *>
(PL_DHashTableOperate(&sNPObjWrappers, npobj, PL_DHASH_LOOKUP));
NS_ASSERTION(entry && PL_DHASH_ENTRY_IS_BUSY(entry),
"Hashtable didn't find what we just added?");
}
if (!obj) {
// OOM? Remove the stale entry from the hash.
PL_DHashTableRawRemove(&sNPObjWrappers, entry);
return nullptr;
}
OnWrapperCreated();
entry->mJSObj = obj;
::JS_SetPrivate(obj, npobj);
// The new JSObject now holds on to npobj
_retainobject(npobj);
return obj;
}
// PLDHashTable enumeration callbacks for destruction code.
static PLDHashOperator
JSObjWrapperPluginDestroyedCallback(PLDHashTable *table, PLDHashEntryHdr *hdr,
uint32_t number, void *arg)
{
JSObjWrapperHashEntry *entry = (JSObjWrapperHashEntry *)hdr;
nsJSObjWrapper *npobj = entry->mJSObjWrapper;
if (npobj->mNpp == arg) {
// Prevent invalidate() and _releaseobject() from touching the hash
// we're enumerating.
const PLDHashTableOps *ops = table->ops;
table->ops = nullptr;
if (npobj->_class && npobj->_class->invalidate) {
npobj->_class->invalidate(npobj);
}
_releaseobject(npobj);
table->ops = ops;
return PL_DHASH_REMOVE;
}
return PL_DHASH_NEXT;
}
// Struct for passing an NPP and a JSContext to
// NPObjWrapperPluginDestroyedCallback
struct NppAndCx
{
NPP npp;
JSContext *cx;
};
static PLDHashOperator
NPObjWrapperPluginDestroyedCallback(PLDHashTable *table, PLDHashEntryHdr *hdr,
uint32_t number, void *arg)
{
NPObjWrapperHashEntry *entry = (NPObjWrapperHashEntry *)hdr;
NppAndCx *nppcx = reinterpret_cast<NppAndCx *>(arg);
if (entry->mNpp == nppcx->npp) {
// Prevent invalidate() and deallocate() from touching the hash
// we're enumerating.
const PLDHashTableOps *ops = table->ops;
table->ops = nullptr;
NPObject *npobj = entry->mNPObj;
if (npobj->_class && npobj->_class->invalidate) {
npobj->_class->invalidate(npobj);
}
#ifdef NS_BUILD_REFCNT_LOGGING
{
int32_t refCnt = npobj->referenceCount;
while (refCnt) {
--refCnt;
NS_LOG_RELEASE(npobj, refCnt, "BrowserNPObject");
}
}
#endif
// Force deallocation of plugin objects since the plugin they came
// from is being torn down.
if (npobj->_class && npobj->_class->deallocate) {
npobj->_class->deallocate(npobj);
} else {
PR_Free(npobj);
}
::JS_SetPrivate(entry->mJSObj, nullptr);
table->ops = ops;
return PL_DHASH_REMOVE;
}
return PL_DHASH_NEXT;
}
// static
void
nsJSNPRuntime::OnPluginDestroy(NPP npp)
{
if (sJSObjWrappers.ops) {
PL_DHashTableEnumerate(&sJSObjWrappers,
JSObjWrapperPluginDestroyedCallback, npp);
}
// Use the safe JSContext here as we're not always able to find the
// JSContext associated with the NPP any more.
nsCOMPtr<nsIThreadJSContextStack> stack =
do_GetService("@mozilla.org/js/xpc/ContextStack;1");
if (!stack) {
NS_ERROR("No context stack available!");
return;
}
JSContext* cx = stack->GetSafeJSContext();
if (!cx) {
NS_ERROR("No safe JS context available!");
return;
}
JSAutoRequest ar(cx);
if (sNPObjWrappers.ops) {
NppAndCx nppcx = { npp, cx };
PL_DHashTableEnumerate(&sNPObjWrappers,
NPObjWrapperPluginDestroyedCallback, &nppcx);
}
// If this plugin was scripted from a webpage, the plugin's
// scriptable object will be on the DOM element's prototype
// chain. Now that the plugin is being destroyed we need to pull the
// plugin's scriptable object out of that prototype chain.
if (!npp) {
return;
}
// Find the plugin instance so that we can (eventually) get to the
// DOM element
nsNPAPIPluginInstance *inst = (nsNPAPIPluginInstance *)npp->ndata;
if (!inst)
return;
nsCOMPtr<nsIDOMElement> element;
inst->GetDOMElement(getter_AddRefs(element));
if (!element)
return;
// Get the DOM element's JS object.
nsCOMPtr<nsIXPConnect> xpc(do_GetService(nsIXPConnect::GetCID()));
if (!xpc)
return;
// OK. Now we have to get our hands on the right scope object, since
// GetWrappedNativeOfNativeObject doesn't call PreCreate and hence won't get
// the right scope if we pass in something bogus. The right scope lives on
// the script global of the element's document.
// XXXbz we MUST have a better way of doing this... perhaps
// GetWrappedNativeOfNativeObject _should_ call preCreate?
nsCOMPtr<nsIContent> content(do_QueryInterface(element));
if (!content) {
return;
}
nsIDocument* doc = content->OwnerDoc();
nsIScriptGlobalObject* sgo = doc->GetScriptGlobalObject();
if (!sgo) {
return;
}
nsCOMPtr<nsIXPConnectWrappedNative> holder;
xpc->GetWrappedNativeOfNativeObject(cx, sgo->GetGlobalJSObject(), content,
NS_GET_IID(nsISupports),
getter_AddRefs(holder));
if (!holder) {
return;
}
JSObject *obj, *proto;
holder->GetJSObject(&obj);
Maybe<JSAutoCompartment> ac;
if (obj) {
ac.construct(cx, obj);
}
// Loop over the DOM element's JS object prototype chain and remove
// all JS objects of the class sNPObjectJSWrapperClass (there should
// be only one, but remove all instances found in case the page put
// more than one of the plugin's scriptable objects on the prototype
// chain).
while (obj && (proto = ::JS_GetPrototype(obj))) {
// Unwrap while checking the jsclass - if the prototype is a wrapper for
// an NP object, that counts too.
if (JS_GetClass(js::UnwrapObject(proto)) == &sNPObjectJSWrapperClass) {
// We found an NPObject on the proto chain, get its prototype...
proto = ::JS_GetPrototype(proto);
// ... and pull it out of the chain.
::JS_SetPrototype(cx, obj, proto);
}
obj = proto;
}
}
// Find the NPP for a NPObject.
static NPP
LookupNPP(NPObject *npobj)
{
if (npobj->_class == &nsJSObjWrapper::sJSObjWrapperNPClass) {
nsJSObjWrapper* o = static_cast<nsJSObjWrapper*>(npobj);
return o->mNpp;
}
NPObjWrapperHashEntry *entry = static_cast<NPObjWrapperHashEntry *>
(PL_DHashTableOperate(&sNPObjWrappers, npobj, PL_DHASH_ADD));
if (PL_DHASH_ENTRY_IS_FREE(entry)) {
return nullptr;
}
NS_ASSERTION(entry->mNpp, "Live NPObject entry w/o an NPP!");
return entry->mNpp;
}
JSBool
CreateNPObjectMember(NPP npp, JSContext *cx, JSObject *obj, NPObject* npobj,
jsid id, NPVariant* getPropertyResult, jsval *vp)
{
NS_ENSURE_TRUE(vp, JS_FALSE);
if (!npobj || !npobj->_class || !npobj->_class->getProperty ||
!npobj->_class->invoke) {
ThrowJSException(cx, "Bad NPObject");
return JS_FALSE;
}
NPObjectMemberPrivate *memberPrivate =
(NPObjectMemberPrivate *)PR_Malloc(sizeof(NPObjectMemberPrivate));
if (!memberPrivate)
return JS_FALSE;
// Make sure to clear all members in case something fails here
// during initialization.
memset(memberPrivate, 0, sizeof(NPObjectMemberPrivate));
JSObject *memobj = ::JS_NewObject(cx, &sNPObjectMemberClass, nullptr, nullptr);
if (!memobj) {
PR_Free(memberPrivate);
return JS_FALSE;
}
*vp = OBJECT_TO_JSVAL(memobj);
::JS_AddValueRoot(cx, vp);
::JS_SetPrivate(memobj, (void *)memberPrivate);
NPIdentifier identifier = JSIdToNPIdentifier(id);
jsval fieldValue;
NPVariant npv;
if (getPropertyResult) {
// Plugin has already handed us the value we want here.
npv = *getPropertyResult;
}
else {
VOID_TO_NPVARIANT(npv);
NPBool hasProperty = npobj->_class->getProperty(npobj, identifier,
&npv);
if (!ReportExceptionIfPending(cx)) {
::JS_RemoveValueRoot(cx, vp);
return JS_FALSE;
}
if (!hasProperty) {
::JS_RemoveValueRoot(cx, vp);
return JS_FALSE;
}
}
fieldValue = NPVariantToJSVal(npp, cx, &npv);
// npobjWrapper is the JSObject through which we make sure we don't
// outlive the underlying NPObject, so make sure it points to the
// real JSObject wrapper for the NPObject.
obj = GetNPObjectWrapper(cx, obj);
memberPrivate->npobjWrapper = obj;
memberPrivate->fieldValue = fieldValue;
memberPrivate->methodName = identifier;
memberPrivate->npp = npp;
::JS_RemoveValueRoot(cx, vp);
return JS_TRUE;
}
static JSBool
NPObjectMember_Convert(JSContext *cx, JSHandleObject obj, JSType type, JSMutableHandleValue vp)
{
NPObjectMemberPrivate *memberPrivate =
(NPObjectMemberPrivate *)::JS_GetInstancePrivate(cx, obj,
&sNPObjectMemberClass,
nullptr);
if (!memberPrivate) {
NS_ERROR("no Ambiguous Member Private data!");
return JS_FALSE;
}
switch (type) {
case JSTYPE_VOID:
case JSTYPE_STRING:
case JSTYPE_NUMBER:
vp.set(memberPrivate->fieldValue);
if (!JSVAL_IS_PRIMITIVE(vp)) {
return JS_DefaultValue(cx, JSVAL_TO_OBJECT(vp), type, vp.address());
}
return JS_TRUE;
case JSTYPE_BOOLEAN:
case JSTYPE_OBJECT:
vp.set(memberPrivate->fieldValue);
return JS_TRUE;
case JSTYPE_FUNCTION:
// Leave this to NPObjectMember_Call.
return JS_TRUE;
default:
NS_ERROR("illegal operation on JSObject prototype object");
return JS_FALSE;
}
}
static void
NPObjectMember_Finalize(JSFreeOp *fop, JSObject *obj)
{
NPObjectMemberPrivate *memberPrivate;
memberPrivate = (NPObjectMemberPrivate *)::JS_GetPrivate(obj);
if (!memberPrivate)
return;
PR_Free(memberPrivate);
}
static JSBool
NPObjectMember_Call(JSContext *cx, unsigned argc, jsval *vp)
{
JSObject *memobj = JSVAL_TO_OBJECT(JS_CALLEE(cx, vp));
NS_ENSURE_TRUE(memobj, JS_FALSE);
NPObjectMemberPrivate *memberPrivate =
(NPObjectMemberPrivate *)::JS_GetInstancePrivate(cx, memobj,
&sNPObjectMemberClass,
JS_ARGV(cx, vp));
if (!memberPrivate || !memberPrivate->npobjWrapper)
return JS_FALSE;
NPObject *npobj = GetNPObject(cx, memberPrivate->npobjWrapper);
if (!npobj) {
ThrowJSException(cx, "Call on invalid member object");
return JS_FALSE;
}
NPVariant npargs_buf[8];
NPVariant *npargs = npargs_buf;
if (argc > (sizeof(npargs_buf) / sizeof(NPVariant))) {
// Our stack buffer isn't large enough to hold all arguments,
// malloc a buffer.
npargs = (NPVariant *)PR_Malloc(argc * sizeof(NPVariant));
if (!npargs) {
ThrowJSException(cx, "Out of memory!");
return JS_FALSE;
}
}
// Convert arguments
uint32_t i;
jsval *argv = JS_ARGV(cx, vp);
for (i = 0; i < argc; ++i) {
if (!JSValToNPVariant(memberPrivate->npp, cx, argv[i], npargs + i)) {
ThrowJSException(cx, "Error converting jsvals to NPVariants!");
if (npargs != npargs_buf) {
PR_Free(npargs);
}
return JS_FALSE;
}
}
NPVariant npv;
JSBool ok;
ok = npobj->_class->invoke(npobj, memberPrivate->methodName,
npargs, argc, &npv);
// Release arguments.
for (i = 0; i < argc; ++i) {
_releasevariantvalue(npargs + i);
}
if (npargs != npargs_buf) {
PR_Free(npargs);
}
if (!ok) {
// ReportExceptionIfPending returns a return value, which is JS_TRUE
// if no exception was thrown. In that case, throw our own.
if (ReportExceptionIfPending(cx))
ThrowJSException(cx, "Error calling method on NPObject!");
return JS_FALSE;
}
JS_SET_RVAL(cx, vp, NPVariantToJSVal(memberPrivate->npp, cx, &npv));
// *vp now owns the value, release our reference.
_releasevariantvalue(&npv);
return ReportExceptionIfPending(cx);
}
static void
NPObjectMember_Trace(JSTracer *trc, JSObject *obj)
{
NPObjectMemberPrivate *memberPrivate =
(NPObjectMemberPrivate *)::JS_GetPrivate(obj);
if (!memberPrivate)
return;
// Our NPIdentifier is not always interned, so we must root it explicitly.
jsid id = NPIdentifierToJSId(memberPrivate->methodName);
if (JSID_IS_STRING(id))
JS_CALL_STRING_TRACER(trc, JSID_TO_STRING(id), "NPObjectMemberPrivate.methodName");
if (!JSVAL_IS_PRIMITIVE(memberPrivate->fieldValue)) {
JS_CALL_VALUE_TRACER(trc, memberPrivate->fieldValue,
"NPObject Member => fieldValue");
}
// There's no strong reference from our private data to the
// NPObject, so make sure to mark the NPObject wrapper to keep the
// NPObject alive as long as this NPObjectMember is alive.
if (memberPrivate->npobjWrapper) {
JS_CALL_OBJECT_TRACER(trc, memberPrivate->npobjWrapper,
"NPObject Member => npobjWrapper");
}
}