1
2 /*
3 * Copyright 2010 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10 #include "SkData.h"
11 #include "SkFlate.h"
12 #include "SkPDFCatalog.h"
13 #include "SkPDFStream.h"
14 #include "SkStream.h"
15
skip_compression(SkPDFCatalog * catalog)16 static bool skip_compression(SkPDFCatalog* catalog) {
17 return catalog->getDocumentFlags() & SkPDFDocument::kNoCompression_Flag;
18 }
19
SkPDFStream(SkStream * stream)20 SkPDFStream::SkPDFStream(SkStream* stream)
21 : fState(kUnused_State),
22 fData(stream) {
23 }
24
SkPDFStream(SkData * data)25 SkPDFStream::SkPDFStream(SkData* data) : fState(kUnused_State) {
26 SkMemoryStream* stream = new SkMemoryStream;
27 stream->setData(data);
28 fData = stream;
29 fData->unref(); // SkRefPtr and new both took a reference.
30 }
31
SkPDFStream(const SkPDFStream & pdfStream)32 SkPDFStream::SkPDFStream(const SkPDFStream& pdfStream)
33 : SkPDFDict(),
34 fState(kUnused_State),
35 fData(pdfStream.fData) {
36 bool removeLength = true;
37 // Don't uncompress an already compressed stream, but we could.
38 if (pdfStream.fState == kCompressed_State) {
39 fState = kCompressed_State;
40 removeLength = false;
41 }
42 SkPDFDict::Iter dict(pdfStream);
43 SkPDFName* key;
44 SkPDFObject* value;
45 SkPDFName lengthName("Length");
46 for (key = dict.next(&value); key != NULL; key = dict.next(&value)) {
47 if (removeLength && *key == lengthName) {
48 continue;
49 }
50 this->insert(key, value);
51 }
52 }
53
~SkPDFStream()54 SkPDFStream::~SkPDFStream() {}
55
emitObject(SkWStream * stream,SkPDFCatalog * catalog,bool indirect)56 void SkPDFStream::emitObject(SkWStream* stream, SkPDFCatalog* catalog,
57 bool indirect) {
58 if (indirect) {
59 return emitIndirectObject(stream, catalog);
60 }
61 if (!this->populate(catalog)) {
62 return fSubstitute->emitObject(stream, catalog, indirect);
63 }
64
65 this->INHERITED::emitObject(stream, catalog, false);
66 stream->writeText(" stream\n");
67 stream->write(fData->getMemoryBase(), fData->getLength());
68 stream->writeText("\nendstream");
69 }
70
getOutputSize(SkPDFCatalog * catalog,bool indirect)71 size_t SkPDFStream::getOutputSize(SkPDFCatalog* catalog, bool indirect) {
72 if (indirect) {
73 return getIndirectOutputSize(catalog);
74 }
75 if (!this->populate(catalog)) {
76 return fSubstitute->getOutputSize(catalog, indirect);
77 }
78
79 return this->INHERITED::getOutputSize(catalog, false) +
80 strlen(" stream\n\nendstream") + fData->getLength();
81 }
82
SkPDFStream()83 SkPDFStream::SkPDFStream() : fState(kUnused_State) {}
84
setData(SkStream * stream)85 void SkPDFStream::setData(SkStream* stream) {
86 fData = stream;
87 }
88
populate(SkPDFCatalog * catalog)89 bool SkPDFStream::populate(SkPDFCatalog* catalog) {
90 if (fState == kUnused_State) {
91 if (!skip_compression(catalog) && SkFlate::HaveFlate()) {
92 SkDynamicMemoryWStream compressedData;
93
94 SkAssertResult(SkFlate::Deflate(fData.get(), &compressedData));
95 if (compressedData.getOffset() < fData->getLength()) {
96 SkMemoryStream* stream = new SkMemoryStream;
97 stream->setData(compressedData.copyToData());
98 fData = stream;
99 fData->unref(); // SkRefPtr and new both took a reference.
100 insertName("Filter", "FlateDecode");
101 }
102 fState = kCompressed_State;
103 } else {
104 fState = kNoCompression_State;
105 }
106 insertInt("Length", fData->getLength());
107 } else if (fState == kNoCompression_State && !skip_compression(catalog) &&
108 SkFlate::HaveFlate()) {
109 if (!fSubstitute.get()) {
110 fSubstitute = new SkPDFStream(*this);
111 fSubstitute->unref(); // SkRefPtr and new both took a reference.
112 catalog->setSubstitute(this, fSubstitute.get());
113 }
114 return false;
115 }
116 return true;
117 }
118