/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * $Id: MemBufInputSource.hpp 932887 2010-04-11 13:04:59Z borisk $ */ #if !defined(XERCESC_INCLUDE_GUARD_MEMBUFINPUTSOURCE_HPP) #define XERCESC_INCLUDE_GUARD_MEMBUFINPUTSOURCE_HPP #include XERCES_CPP_NAMESPACE_BEGIN class BinInputStream; /** * This class is a derivative of the standard InputSource class. It provides * for the parser access to data stored in a memory buffer. The type of * buffer and its host specific attributes are of little concern here. The * only real requirement is that the memory be readable by the current * process. * * Note that the memory buffer size is expressed in bytes, not in * characters. If you pass it text data, you must account for the bytes * per character when indicating the buffer size. * * As with all InputSource derivatives. The primary objective of an input * source is to create an input stream via which the parser can spool in * data from the referenced source. In this case, there are two options * available. * * The passed buffer can be adopted or merely referenced. If it is adopted, * then it must be dynamically allocated and will be destroyed when the * input source is destroyed (no reference counting!.) If not adopted, the * caller must insure that it remains valid until the input source object * is destroyed. * * The other option indicates whether each stream created for this input * source should get its own copy of the data, or whether it should just * stream the data directly from this object's copy of the data. The same * rules apply here, in that the buffer must either be copied by the * stream or it must remain valid until the stream is destroyed. */ class XMLPARSER_EXPORT MemBufInputSource : public InputSource { public : // ----------------------------------------------------------------------- // Constructors and Destructor // ----------------------------------------------------------------------- /** @name Constructors */ //@{ /** * A memory buffer input source is constructed from a buffer of byte * data, and the count of bytes in that buffer. The parser will parse * from this memory buffer until it has eaten the indicated number of * bytes. * * Note that the system id provided serves two purposes. Firstly it is * going to be displayed in error messages as the source of the error. * And secondly, any entities which are referred to from this entity * via relative paths/URLs will be relative to this fake system id. * * @param srcDocBytes The actual data buffer to be parsed from. * @param byteCount The count of bytes (not characters, bytes!) * in the buffer. * @param bufId A fake system id for the buffer. * @param adoptBuffer Indicates whether this object should adopt * the buffer (i.e. become responsible for * deletion) or just * use it in place. * @param manager Pointer to the memory manager to be used to * allocate objects. */ MemBufInputSource ( const XMLByte* const srcDocBytes , const XMLSize_t byteCount , const XMLCh* const bufId , const bool adoptBuffer = false , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager ); /** * This constructor is identical to the previous one, except that it takes * the fake system id in local code page form and transcodes it internally. */ MemBufInputSource ( const XMLByte* const srcDocBytes , const XMLSize_t byteCount , const char* const bufId , const bool adoptBuffer = false , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager ); //@} /** @name Destructor */ //@{ /** * If the buffer was adopted, the copy made during construction is deleted * at this point. */ ~MemBufInputSource(); //@} // ----------------------------------------------------------------------- // Virtual input source interface // ----------------------------------------------------------------------- /** @name Virtual methods */ //@{ /** * This method will return a binary input stream derivative that will * parse from the memory buffer. If setCopyBufToStream() has been set, * then the stream will make its own copy. Otherwise, it will use the * buffer as is (in which case it must remain valid until the stream * is no longer in use, i.e. the parse completes.) * * @return A dynamically allocated binary input stream derivative that * can parse from the memory buffer. */ BinInputStream* makeStream() const; //@} // ----------------------------------------------------------------------- // Setter methods // ----------------------------------------------------------------------- /** @name Setter methods */ //@{ /** * By default, for safety's sake, each newly created stream from this * input source will make its own copy of the buffer to stream from. This * avoids having to deal with aliasing of the buffer for simple work. But, * for higher performance applications or for large buffers, this is * obviously not optimal. * * In such cases, you can call this method to turn off that default * action. Once turned off, the streams will just get a pointer to the * buffer and parse directly from that. In this case, you must insure that * the buffer remains valid for as long as any parse events are still * using it. * * @param newState The new boolean flag state to set. */ void setCopyBufToStream(const bool newState); /** * This methods allows the MemBufInputSource to be used for more than * one input source, instead of destructing/constructing another * MemBufInputSource. * * @param srcDocBytes The actual data buffer to be parsed from. * @param byteCount The count of bytes (not characters, bytes!) * in the buffer. */ void resetMemBufInputSource(const XMLByte* const srcDocBytes , const XMLSize_t byteCount); //@} private : // ----------------------------------------------------------------------- // Unimplemented constructors and operators // ----------------------------------------------------------------------- MemBufInputSource(const MemBufInputSource&); MemBufInputSource& operator=(const MemBufInputSource&); // ----------------------------------------------------------------------- // Private data members // // fAdopted // Indicates whether the buffer is adopted or not. If so, then it // is destroyed when the input source is destroyed. // // fByteCount // The size of the source document. // // fCopyBufToStream // This defaults to true (the safe option), which causes it to // give a copy of the buffer to any streams it creates. If you set // it to false, it will allow the streams to just reference the // buffer (in which case this input source must stay alive as long // as the buffer is in use by the stream.) // // fSrcBytes // The source memory buffer that is being spooled from. Whether it // belongs to the this input source or not is controlled by the // fAdopted flag. // ----------------------------------------------------------------------- bool fAdopted; XMLSize_t fByteCount; bool fCopyBufToStream; const XMLByte* fSrcBytes; }; inline void MemBufInputSource::setCopyBufToStream(const bool newState) { fCopyBufToStream = newState; } XERCES_CPP_NAMESPACE_END #endif