michael@0: 
michael@0: /*
michael@0:  * Copyright 2010 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkData.h"
michael@0: #include "SkFlate.h"
michael@0: #include "SkPDFCatalog.h"
michael@0: #include "SkPDFStream.h"
michael@0: #include "SkStream.h"
michael@0: 
michael@0: static bool skip_compression(SkPDFCatalog* catalog) {
michael@0:     return SkToBool(catalog->getDocumentFlags() &
michael@0:                     SkPDFDocument::kFavorSpeedOverSize_Flags);
michael@0: }
michael@0: 
michael@0: SkPDFStream::SkPDFStream(SkStream* stream) : fState(kUnused_State) {
michael@0:     setData(stream);
michael@0: }
michael@0: 
michael@0: SkPDFStream::SkPDFStream(SkData* data) : fState(kUnused_State) {
michael@0:     setData(data);
michael@0: }
michael@0: 
michael@0: SkPDFStream::SkPDFStream(const SkPDFStream& pdfStream)
michael@0:         : SkPDFDict(),
michael@0:           fState(kUnused_State) {
michael@0:     setData(pdfStream.fData.get());
michael@0:     bool removeLength = true;
michael@0:     // Don't uncompress an already compressed stream, but we could.
michael@0:     if (pdfStream.fState == kCompressed_State) {
michael@0:         fState = kCompressed_State;
michael@0:         removeLength = false;
michael@0:     }
michael@0:     SkPDFDict::Iter dict(pdfStream);
michael@0:     SkPDFName* key;
michael@0:     SkPDFObject* value;
michael@0:     SkPDFName lengthName("Length");
michael@0:     for (key = dict.next(&value); key != NULL; key = dict.next(&value)) {
michael@0:         if (removeLength && *key == lengthName) {
michael@0:             continue;
michael@0:         }
michael@0:         this->insert(key, value);
michael@0:     }
michael@0: }
michael@0: 
michael@0: SkPDFStream::~SkPDFStream() {}
michael@0: 
michael@0: void SkPDFStream::emitObject(SkWStream* stream, SkPDFCatalog* catalog,
michael@0:                              bool indirect) {
michael@0:     if (indirect) {
michael@0:         return emitIndirectObject(stream, catalog);
michael@0:     }
michael@0:     if (!this->populate(catalog)) {
michael@0:         return fSubstitute->emitObject(stream, catalog, indirect);
michael@0:     }
michael@0: 
michael@0:     this->INHERITED::emitObject(stream, catalog, false);
michael@0:     stream->writeText(" stream\n");
michael@0:     stream->writeStream(fData.get(), fData->getLength());
michael@0:     fData->rewind();
michael@0:     stream->writeText("\nendstream");
michael@0: }
michael@0: 
michael@0: size_t SkPDFStream::getOutputSize(SkPDFCatalog* catalog, bool indirect) {
michael@0:     if (indirect) {
michael@0:         return getIndirectOutputSize(catalog);
michael@0:     }
michael@0:     if (!this->populate(catalog)) {
michael@0:         return fSubstitute->getOutputSize(catalog, indirect);
michael@0:     }
michael@0: 
michael@0:     return this->INHERITED::getOutputSize(catalog, false) +
michael@0:         strlen(" stream\n\nendstream") + fData->getLength();
michael@0: }
michael@0: 
michael@0: SkPDFStream::SkPDFStream() : fState(kUnused_State) {}
michael@0: 
michael@0: void SkPDFStream::setData(SkData* data) {
michael@0:     SkMemoryStream* stream = new SkMemoryStream;
michael@0:     stream->setData(data);
michael@0:     fData.reset(stream);  // Transfer ownership.
michael@0: }
michael@0: 
michael@0: void SkPDFStream::setData(SkStream* stream) {
michael@0:     // Code assumes that the stream starts at the beginning and is rewindable.
michael@0:     if (stream) {
michael@0:         SkASSERT(stream->getPosition() == 0);
michael@0:         SkASSERT(stream->rewind());
michael@0:     }
michael@0:     fData.reset(stream);
michael@0:     SkSafeRef(stream);
michael@0: }
michael@0: 
michael@0: bool SkPDFStream::populate(SkPDFCatalog* catalog) {
michael@0:     if (fState == kUnused_State) {
michael@0:         if (!skip_compression(catalog) && SkFlate::HaveFlate()) {
michael@0:             SkDynamicMemoryWStream compressedData;
michael@0: 
michael@0:             SkAssertResult(SkFlate::Deflate(fData.get(), &compressedData));
michael@0:             if (compressedData.getOffset() < fData->getLength()) {
michael@0:                 SkMemoryStream* stream = new SkMemoryStream;
michael@0:                 stream->setData(compressedData.copyToData())->unref();
michael@0:                 fData.reset(stream);  // Transfer ownership.
michael@0:                 insertName("Filter", "FlateDecode");
michael@0:             }
michael@0:             fState = kCompressed_State;
michael@0:         } else {
michael@0:             fState = kNoCompression_State;
michael@0:         }
michael@0:         insertInt("Length", fData->getLength());
michael@0:     } else if (fState == kNoCompression_State && !skip_compression(catalog) &&
michael@0:                SkFlate::HaveFlate()) {
michael@0:         if (!fSubstitute.get()) {
michael@0:             fSubstitute.reset(new SkPDFStream(*this));
michael@0:             catalog->setSubstitute(this, fSubstitute.get());
michael@0:         }
michael@0:         return false;
michael@0:     }
michael@0:     return true;
michael@0: }