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#ifndef SkPDFStream_DEFINED
11#define SkPDFStream_DEFINED
12
13#include "SkPDFTypes.h"
14#include "SkRefCnt.h"
15#include "SkStream.h"
16#include "SkTemplates.h"
17
18class SkPDFCatalog;
19
20/** \class SkPDFStream
21
22    A stream object in a PDF.  Note, all streams must be indirect objects (via
23    SkObjRef).
24    TODO(vandebo): SkStream should be replaced by SkStreamRewindable when that
25    is feasible.
26*/
27class SkPDFStream : public SkPDFDict {
28    SK_DECLARE_INST_COUNT(SkPDFStream)
29public:
30    /** Create a PDF stream. A Length entry is automatically added to the
31     *  stream dictionary. The stream may be retained (stream->ref() may be
32     *  called) so its contents must not be changed after calling this.
33     *  @param data  The data part of the stream.
34     */
35    explicit SkPDFStream(SkData* data);
36    /** Deprecated constructor. */
37    explicit SkPDFStream(SkStream* stream);
38    /** Create a PDF stream with the same content and dictionary entries
39     *  as the passed one.
40     */
41    explicit SkPDFStream(const SkPDFStream& pdfStream);
42    virtual ~SkPDFStream();
43
44    // The SkPDFObject interface.
45    virtual void emitObject(SkWStream* stream, SkPDFCatalog* catalog,
46                            bool indirect);
47    virtual size_t getOutputSize(SkPDFCatalog* catalog, bool indirect);
48
49protected:
50    enum State {
51        kUnused_State,         //!< The stream hasn't been requested yet.
52        kNoCompression_State,  //!< The stream's been requested in an
53                               //   uncompressed form.
54        kCompressed_State,     //!< The stream's already been compressed.
55    };
56
57    /* Create a PDF stream with no data.  The setData method must be called to
58     * set the data.
59     */
60    SkPDFStream();
61
62    // Populate the stream dictionary.  This method returns false if
63    // fSubstitute should be used.
64    virtual bool populate(SkPDFCatalog* catalog);
65
66    void setSubstitute(SkPDFStream* stream) {
67        fSubstitute.reset(stream);
68    }
69
70    SkPDFStream* getSubstitute() {
71        return fSubstitute.get();
72    }
73
74    void setData(SkData* data);
75    void setData(SkStream* stream);
76
77    SkStream* getData() {
78        return fData.get();
79    }
80
81    void setState(State state) {
82        fState = state;
83    }
84
85    State getState() {
86        return fState;
87    }
88
89private:
90    // Indicates what form (or if) the stream has been requested.
91    State fState;
92
93    // TODO(vandebo): Use SkData (after removing deprecated constructor).
94    SkAutoTUnref<SkStream> fData;
95    SkAutoTUnref<SkPDFStream> fSubstitute;
96
97    typedef SkPDFDict INHERITED;
98};
99
100#endif
101