The Tor Browser: js/src/jsonparser.h@6474c204b198 (annotated)

js/src/jsonparser.h@6474c204b198 (annotated)

js/src/jsonparser.h

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * vim: set ts=8 sts=4 et sw=4 tw=99:
  * 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 jsonparser_h
 #define jsonparser_h
 #include "mozilla/Attributes.h"
 #include "ds/IdValuePair.h"
 #include "vm/String.h"
 namespace js {
 class MOZ_STACK_CLASS JSONParser : private AutoGCRooter
 {
   public:
     enum ErrorHandling { RaiseError, NoError };
   private:
     /* Data members */
     JSContext * const cx;
     JS::ConstTwoByteChars current;
     const JS::ConstTwoByteChars begin, end;
     Value v;
     const ErrorHandling errorHandling;
     enum Token { String, Number, True, False, Null,
                  ArrayOpen, ArrayClose,
                  ObjectOpen, ObjectClose,
                  Colon, Comma,
                  OOM, Error };
     // State related to the parser's current position. At all points in the
     // parse this keeps track of the stack of arrays and objects which have
     // been started but not finished yet. The actual JS object is not
     // allocated until the literal is closed, so that the result can be sized
     // according to its contents and have its type and shape filled in using
     // caches.
     // State for an array that is currently being parsed. This includes all
     // elements that have been seen so far.
     typedef Vector<Value, 20> ElementVector;
     // State for an object that is currently being parsed. This includes all
     // the key/value pairs that have been seen so far.
     typedef Vector<IdValuePair, 10> PropertyVector;
     // Possible states the parser can be in between values.
     enum ParserState {
         // An array element has just being parsed.
         FinishArrayElement,
         // An object property has just been parsed.
         FinishObjectMember,
         // At the start of the parse, before any values have been processed.
         JSONValue
     };
     // Stack element for an in progress array or object.
     struct StackEntry {
         ElementVector &elements() {
             JS_ASSERT(state == FinishArrayElement);
             return * static_cast<ElementVector *>(vector);
         }
         PropertyVector &properties() {
             JS_ASSERT(state == FinishObjectMember);
             return * static_cast<PropertyVector *>(vector);
         }
         StackEntry(ElementVector *elements)
           : state(FinishArrayElement), vector(elements)
         {}
         StackEntry(PropertyVector *properties)
           : state(FinishObjectMember), vector(properties)
         {}
         ParserState state;
       private:
         void *vector;
     };
     // All in progress arrays and objects being parsed, in order from outermost
     // to innermost.
     Vector<StackEntry, 10> stack;
     // Unused element and property vectors for previous in progress arrays and
     // objects. These vectors are not freed until the end of the parse to avoid
     // unnecessary freeing and allocation.
     Vector<ElementVector*, 5> freeElements;
     Vector<PropertyVector*, 5> freeProperties;
 #ifdef DEBUG
     Token lastToken;
 #endif
   public:
     /* Public API */
     /* Create a parser for the provided JSON data. */
     JSONParser(JSContext *cx, JS::ConstTwoByteChars data, size_t length,
                ErrorHandling errorHandling = RaiseError)
       : AutoGCRooter(cx, JSONPARSER),
         cx(cx),
         current(data),
         begin(data),
         end((data + length).get(), data.get(), length),
         errorHandling(errorHandling),
         stack(cx),
         freeElements(cx),
         freeProperties(cx)
 #ifdef DEBUG
       , lastToken(Error)
 #endif
     {
         JS_ASSERT(current <= end);
     }
     ~JSONParser();
     /*
      * Parse the JSON data specified at construction time.  If it parses
      * successfully, store the prescribed value in *vp and return true.  If an
      * internal error (e.g. OOM) occurs during parsing, return false.
      * Otherwise, if invalid input was specifed but no internal error occurred,
      * behavior depends upon the error handling specified at construction: if
      * error handling is RaiseError then throw a SyntaxError and return false,
      * otherwise return true and set *vp to |undefined|.  (JSON syntax can't
      * represent |undefined|, so the JSON data couldn't have specified it.)
      */
     bool parse(MutableHandleValue vp);
   private:
     Value numberValue() const {
         JS_ASSERT(lastToken == Number);
         JS_ASSERT(v.isNumber());
         return v;
     }
     Value stringValue() const {
         JS_ASSERT(lastToken == String);
         JS_ASSERT(v.isString());
         return v;
     }
     JSAtom *atomValue() const {
         Value strval = stringValue();
         return &strval.toString()->asAtom();
     }
     Token token(Token t) {
         JS_ASSERT(t != String);
         JS_ASSERT(t != Number);
 #ifdef DEBUG
         lastToken = t;
 #endif
         return t;
     }
     Token stringToken(JSString *str) {
         this->v = StringValue(str);
 #ifdef DEBUG
         lastToken = String;
 #endif
         return String;
     }
     Token numberToken(double d) {
         this->v = NumberValue(d);
 #ifdef DEBUG
         lastToken = Number;
 #endif
         return Number;
     }
     enum StringType { PropertyName, LiteralValue };
     template<StringType ST> Token readString();
     Token readNumber();
     Token advance();
     Token advancePropertyName();
     Token advancePropertyColon();
     Token advanceAfterProperty();
     Token advanceAfterObjectOpen();
     Token advanceAfterArrayElement();
     void error(const char *msg);
     bool errorReturn();
     JSObject *createFinishedObject(PropertyVector &properties);
     bool finishObject(MutableHandleValue vp, PropertyVector &properties);
     bool finishArray(MutableHandleValue vp, ElementVector &elements);
     void getTextPosition(uint32_t *column, uint32_t *line);
     friend void AutoGCRooter::trace(JSTracer *trc);
     void trace(JSTracer *trc);
   private:
     JSONParser(const JSONParser &other) MOZ_DELETE;
     void operator=(const JSONParser &other) MOZ_DELETE;
 };
 } /* namespace js */
 #endif /* jsonparser_h */

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js/src/jsonparser.h@6474c204b198 (annotated)

js/src/jsonparser.h