gecko-dev/dom/base/nsJSUtils.h

156 lines
4.5 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/. */
#ifndef nsJSUtils_h__
#define nsJSUtils_h__
/**
* This is not a generated file. It contains common utility functions
* invoked from the JavaScript code generated from IDL interfaces.
* The goal of the utility functions is to cut down on the size of
* the generated code itself.
*/
#include "mozilla/Assertions.h"
#include "jsapi.h"
#include "nsString.h"
class nsIScriptContext;
class nsIScriptGlobalObject;
class nsJSUtils
{
public:
static bool GetCallingLocation(JSContext* aContext, const char* *aFilename,
uint32_t* aLineno);
static nsIScriptGlobalObject *GetStaticScriptGlobal(JSObject* aObj);
static nsIScriptContext *GetStaticScriptContext(JSObject* aObj);
static nsIScriptGlobalObject *GetDynamicScriptGlobal(JSContext *aContext);
static nsIScriptContext *GetDynamicScriptContext(JSContext *aContext);
/**
* Retrieve the inner window ID based on the given JSContext.
*
* @param JSContext aContext
* The JSContext from which you want to find the inner window ID.
*
* @returns uint64_t the inner window ID.
*/
static uint64_t GetCurrentlyRunningCodeInnerWindowID(JSContext *aContext);
/**
* Report a pending exception on aContext, if any. Note that this
* can be called when the context has a JS stack. If that's the
* case, the stack will be set aside before reporting the exception.
*/
static void ReportPendingException(JSContext *aContext);
static nsresult CompileFunction(JSContext* aCx,
JS::HandleObject aTarget,
JS::CompileOptions& aOptions,
const nsACString& aName,
uint32_t aArgCount,
const char** aArgArray,
const nsAString& aBody,
JSObject** aFunctionObject);
struct EvaluateOptions {
bool coerceToString;
bool reportUncaught;
explicit EvaluateOptions() : coerceToString(false)
, reportUncaught(true)
{}
EvaluateOptions& setCoerceToString(bool aCoerce) {
coerceToString = aCoerce;
return *this;
}
EvaluateOptions& setReportUncaught(bool aReport) {
reportUncaught = aReport;
return *this;
}
};
static nsresult EvaluateString(JSContext* aCx,
const nsAString& aScript,
JS::Handle<JSObject*> aScopeObject,
JS::CompileOptions &aCompileOptions,
EvaluateOptions& aEvaluateOptions,
JS::Value* aRetValue,
void **aOffThreadToken = nullptr);
};
class nsDependentJSString : public nsDependentString
{
public:
/**
* In the case of string ids, getting the string's chars is infallible, so
* the dependent string can be constructed directly.
*/
explicit nsDependentJSString(JS::Handle<jsid> id)
: nsDependentString(JS_GetInternedStringChars(JSID_TO_STRING(id)),
JS_GetStringLength(JSID_TO_STRING(id)))
{
}
/**
* Ditto for flat strings.
*/
explicit nsDependentJSString(JSFlatString* fstr)
: nsDependentString(JS_GetFlatStringChars(fstr),
JS_GetStringLength(JS_FORGET_STRING_FLATNESS(fstr)))
{
}
/**
* For all other strings, the nsDependentJSString object should be default
* constructed, which leaves it empty (this->IsEmpty()), and initialized with
* one of the init() methods below.
*/
nsDependentJSString()
{
}
bool init(JSContext* aContext, JSString* str)
{
size_t length;
const jschar* chars = JS_GetStringCharsZAndLength(aContext, str, &length);
if (!chars)
return false;
NS_ASSERTION(IsEmpty(), "init() on initialized string");
nsDependentString* base = this;
new(base) nsDependentString(chars, length);
return true;
}
bool init(JSContext* aContext, const JS::Value &v)
{
return init(aContext, JSVAL_TO_STRING(v));
}
void init(JSFlatString* fstr)
{
MOZ_ASSERT(IsEmpty(), "init() on initialized string");
new(this) nsDependentJSString(fstr);
}
~nsDependentJSString()
{
}
};
#endif /* nsJSUtils_h__ */