/src/libreoffice/sax/source/tools/CachedOutputStream.hxx
Line | Count | Source |
1 | | /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ |
2 | | /* |
3 | | * This file is part of the LibreOffice project. |
4 | | * |
5 | | * This Source Code Form is subject to the terms of the Mozilla Public |
6 | | * License, v. 2.0. If a copy of the MPL was not distributed with this |
7 | | * file, You can obtain one at http://mozilla.org/MPL/2.0/. |
8 | | */ |
9 | | |
10 | | #pragma once |
11 | | |
12 | | #include <sal/types.h> |
13 | | #include <rtl/byteseq.hxx> |
14 | | |
15 | | #include <com/sun/star/io/XOutputStream.hpp> |
16 | | #include <com/sun/star/uno/Sequence.hxx> |
17 | | |
18 | | #include <cstring> |
19 | | #include <memory> |
20 | | |
21 | | namespace sax_fastparser { |
22 | | |
23 | | typedef rtl::ByteSequence Int8Sequence; |
24 | | |
25 | | class ForMergeBase |
26 | | { |
27 | | public: |
28 | 0 | virtual ~ForMergeBase() {} |
29 | | virtual void append( const Int8Sequence& rWhat ) = 0; |
30 | | }; |
31 | | |
32 | | class CachedOutputStream |
33 | | { |
34 | | /// When buffer hits this size, it's written to mxOutputStream |
35 | | static const sal_Int32 mnMaximumSize = 0x100000; // 1Mbyte |
36 | | |
37 | | /// ForMerge structure is used for sorting elements in Writer |
38 | | std::shared_ptr< ForMergeBase > mpForMerge; |
39 | | const Int8Sequence maCache; |
40 | | /// Output stream, usually writing data into files. |
41 | | css::uno::Reference< css::io::XOutputStream > mxOutputStream; |
42 | | uno_Sequence *pSeq; |
43 | | sal_Int32 mnCacheWrittenSize; |
44 | | bool mbWriteToOutStream; |
45 | | |
46 | | public: |
47 | 0 | CachedOutputStream() : maCache(mnMaximumSize, rtl::BYTESEQ_NODEFAULT) |
48 | 0 | , pSeq(maCache.get()) |
49 | 0 | , mnCacheWrittenSize(0) |
50 | 0 | , mbWriteToOutStream(true) |
51 | 0 | {} |
52 | | |
53 | | const css::uno::Reference< css::io::XOutputStream >& getOutputStream() const |
54 | 0 | { |
55 | 0 | return mxOutputStream; |
56 | 0 | } |
57 | | |
58 | | void setOutputStream( const css::uno::Reference< css::io::XOutputStream >& xOutputStream ) |
59 | 0 | { |
60 | 0 | mxOutputStream = xOutputStream; |
61 | 0 | } |
62 | | |
63 | | void setOutput(const std::shared_ptr<ForMergeBase>& pForMerge) |
64 | 0 | { |
65 | 0 | flush(); |
66 | 0 | mbWriteToOutStream = false; |
67 | 0 | mpForMerge = pForMerge; |
68 | 0 | } |
69 | | |
70 | | void resetOutputToStream() |
71 | 0 | { |
72 | 0 | flush(); |
73 | 0 | mbWriteToOutStream = true; |
74 | 0 | mpForMerge.reset(); |
75 | 0 | } |
76 | | |
77 | | /// cache string and if limit is hit, flush |
78 | | void writeBytes( const sal_Int8* pStr, sal_Int32 nLen ) |
79 | 0 | { |
80 | | // Write when the buffer gets big enough |
81 | 0 | if (mnCacheWrittenSize + nLen > mnMaximumSize) |
82 | 0 | { |
83 | 0 | flush(); |
84 | | |
85 | | // Writer does some elements sorting, so it can accumulate |
86 | | // pretty big strings in FastSaxSerializer::ForMerge. |
87 | | // In that case, just flush data and write immediately. |
88 | 0 | if (nLen > mnMaximumSize) |
89 | 0 | { |
90 | 0 | if (mbWriteToOutStream) |
91 | 0 | mxOutputStream->writeBytes( css::uno::Sequence<sal_Int8>(pStr, nLen) ); |
92 | 0 | else |
93 | 0 | mpForMerge->append( Int8Sequence(pStr, nLen) ); |
94 | 0 | return; |
95 | 0 | } |
96 | 0 | } |
97 | | |
98 | 0 | memcpy(pSeq->elements + mnCacheWrittenSize, pStr, nLen); |
99 | 0 | mnCacheWrittenSize += nLen; |
100 | 0 | } |
101 | | |
102 | | /// immediately write buffer into mxOutputStream and clear |
103 | | void flush() |
104 | 0 | { |
105 | | // resize the Sequence to written size |
106 | 0 | pSeq->nElements = mnCacheWrittenSize; |
107 | 0 | if (mbWriteToOutStream) |
108 | 0 | mxOutputStream->writeBytes( css::uno::toUnoSequence(maCache) ); |
109 | 0 | else |
110 | 0 | mpForMerge->append( maCache ); |
111 | | // and next time write to the beginning |
112 | 0 | mnCacheWrittenSize = 0; |
113 | 0 | } |
114 | | }; |
115 | | |
116 | | } |
117 | | |
118 | | /* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |