michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "JSStreamWriter.h"
michael@0: 
michael@0: #include "mozilla/ArrayUtils.h" // for ArrayLength
michael@0: #include "nsDataHashtable.h"
michael@0: #include "nsString.h"
michael@0: #include "nsTArray.h"
michael@0: #include "nsUTF8Utils.h"
michael@0: 
michael@0: #if _MSC_VER
michael@0:  #define snprintf _snprintf
michael@0: #endif
michael@0: 
michael@0: #define ARRAY (void*)1
michael@0: #define OBJECT (void*)2
michael@0: 
michael@0: // Escape a UTF8 string to a stream. When an illegal encoding
michael@0: // is found it will insert "INVALID" and the function will return.
michael@0: static void EscapeToStream(std::ostream& stream, const char* str) {
michael@0:   stream << "\"";
michael@0: 
michael@0:   size_t len = strlen(str);
michael@0:   const char* end = &str[len];
michael@0:   while (str < end) {
michael@0:     bool err;
michael@0:     const char* utf8CharStart = str;
michael@0:     uint32_t ucs4Char = UTF8CharEnumerator::NextChar(&str, end, &err);
michael@0: 
michael@0:     if (err) {
michael@0:       // Encoding error
michael@0:       stream << "INVALID\"";
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // See http://www.ietf.org/rfc/rfc4627.txt?number=4627
michael@0:     // characters that must be escaped: quotation mark,
michael@0:     // reverse solidus, and the control characters
michael@0:     // (U+0000 through U+001F).
michael@0:     if (ucs4Char == '\"') {
michael@0:       stream << "\\\"";
michael@0:     } else if (ucs4Char == '\\') {
michael@0:       stream << "\\\\";
michael@0:     } else if (ucs4Char > 0xFF) {
michael@0:       char16_t chr[2];
michael@0:       ConvertUTF8toUTF16 encoder(chr);
michael@0:       encoder.write(utf8CharStart, uint32_t(str-utf8CharStart));
michael@0:       char escChar[13];
michael@0:       snprintf(escChar, mozilla::ArrayLength(escChar), "\\u%04X\\u%04X", chr[0], chr[1]);
michael@0:       stream << escChar;
michael@0:     } else if (ucs4Char < 0x1F || ucs4Char > 0xFF) {
michael@0:       char escChar[7];
michael@0:       snprintf(escChar, mozilla::ArrayLength(escChar), "\\u%04X", ucs4Char);
michael@0:       stream << escChar;
michael@0:     } else {
michael@0:       stream << char(ucs4Char);
michael@0:     }
michael@0:   }
michael@0:   stream << "\"";
michael@0: }
michael@0: 
michael@0: JSStreamWriter::JSStreamWriter(std::ostream& aStream)
michael@0:   : mStream(aStream)
michael@0:   , mNeedsComma(false)
michael@0:   , mNeedsName(false)
michael@0: { }
michael@0: 
michael@0: JSStreamWriter::~JSStreamWriter()
michael@0: {
michael@0:   MOZ_ASSERT(mStack.GetSize() == 0);
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::BeginObject()
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == ARRAY) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   mStream << "{";
michael@0:   mNeedsComma = false;
michael@0:   mNeedsName = true;
michael@0:   mStack.Push(OBJECT);
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::EndObject()
michael@0: {
michael@0:   MOZ_ASSERT(mStack.Peek() == OBJECT);
michael@0:   mStream << "}";
michael@0:   mNeedsComma = true;
michael@0:   mNeedsName = false;
michael@0:   mStack.Pop();
michael@0:   if (mStack.GetSize() > 0 && mStack.Peek() == OBJECT) {
michael@0:     mNeedsName = true;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::BeginArray()
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == ARRAY) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   mStream << "[";
michael@0:   mNeedsComma = false;
michael@0:   mStack.Push(ARRAY);
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::EndArray()
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   MOZ_ASSERT(mStack.Peek() == ARRAY);
michael@0:   mStream << "]";
michael@0:   mNeedsComma = true;
michael@0:   mStack.Pop();
michael@0:   if (mStack.GetSize() > 0 && mStack.Peek() == OBJECT) {
michael@0:     mNeedsName = true;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::Name(const char *aName)
michael@0: {
michael@0:   MOZ_ASSERT(mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == OBJECT) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   EscapeToStream(mStream, aName);
michael@0:   mStream << ":";
michael@0:   mNeedsName = false;
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::Value(int aValue)
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == ARRAY) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   mStream << aValue;
michael@0:   mNeedsComma = true;
michael@0:   if (mStack.Peek() == OBJECT) {
michael@0:     mNeedsName = true;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::Value(double aValue)
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == ARRAY) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   mStream.precision(18);
michael@0:   mStream << aValue;
michael@0:   mNeedsComma = true;
michael@0:   if (mStack.Peek() == OBJECT) {
michael@0:     mNeedsName = true;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: JSStreamWriter::Value(const char *aValue)
michael@0: {
michael@0:   MOZ_ASSERT(!mNeedsName);
michael@0:   if (mNeedsComma && mStack.Peek() == ARRAY) {
michael@0:     mStream << ",";
michael@0:   }
michael@0:   EscapeToStream(mStream, aValue);
michael@0:   mNeedsComma = true;
michael@0:   if (mStack.Peek() == OBJECT) {
michael@0:     mNeedsName = true;
michael@0:   }
michael@0: }