1
2 /*
3 * Copyright 2010 The Android Open Source Project
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 "SkStream.h"
13
14 #ifndef SK_ZLIB_INCLUDE
HaveFlate()15 bool SkFlate::HaveFlate() { return false; }
Deflate(SkStream *,SkWStream *)16 bool SkFlate::Deflate(SkStream*, SkWStream*) { return false; }
Deflate(const void *,size_t,SkWStream *)17 bool SkFlate::Deflate(const void*, size_t, SkWStream*) { return false; }
Deflate(const SkData *,SkWStream *)18 bool SkFlate::Deflate(const SkData*, SkWStream*) { return false; }
Inflate(SkStream *,SkWStream *)19 bool SkFlate::Inflate(SkStream*, SkWStream*) { return false; }
20 #else
21
22 // static
HaveFlate()23 bool SkFlate::HaveFlate() {
24 return true;
25 }
26
27 namespace {
28
29 #include SK_ZLIB_INCLUDE
30
31 // static
32 const size_t kBufferSize = 1024;
33
doFlate(bool compress,SkStream * src,SkWStream * dst)34 bool doFlate(bool compress, SkStream* src, SkWStream* dst) {
35 uint8_t inputBuffer[kBufferSize];
36 uint8_t outputBuffer[kBufferSize];
37 z_stream flateData;
38 flateData.zalloc = NULL;
39 flateData.zfree = NULL;
40 flateData.next_in = NULL;
41 flateData.avail_in = 0;
42 flateData.next_out = outputBuffer;
43 flateData.avail_out = kBufferSize;
44 int rc;
45 if (compress)
46 rc = deflateInit(&flateData, Z_DEFAULT_COMPRESSION);
47 else
48 rc = inflateInit(&flateData);
49 if (rc != Z_OK)
50 return false;
51
52 uint8_t* input = (uint8_t*)src->getMemoryBase();
53 size_t inputLength = src->getLength();
54 if (input == NULL || inputLength == 0) {
55 input = NULL;
56 flateData.next_in = inputBuffer;
57 flateData.avail_in = 0;
58 } else {
59 flateData.next_in = input;
60 flateData.avail_in = inputLength;
61 }
62
63 rc = Z_OK;
64 while (true) {
65 if (flateData.avail_out < kBufferSize) {
66 if (!dst->write(outputBuffer, kBufferSize - flateData.avail_out)) {
67 rc = Z_BUF_ERROR;
68 break;
69 }
70 flateData.next_out = outputBuffer;
71 flateData.avail_out = kBufferSize;
72 }
73 if (rc != Z_OK)
74 break;
75 if (flateData.avail_in == 0) {
76 if (input != NULL)
77 break;
78 size_t read = src->read(&inputBuffer, kBufferSize);
79 if (read == 0)
80 break;
81 flateData.next_in = inputBuffer;
82 flateData.avail_in = read;
83 }
84 if (compress)
85 rc = deflate(&flateData, Z_NO_FLUSH);
86 else
87 rc = inflate(&flateData, Z_NO_FLUSH);
88 }
89 while (rc == Z_OK) {
90 if (compress)
91 rc = deflate(&flateData, Z_FINISH);
92 else
93 rc = inflate(&flateData, Z_FINISH);
94 if (flateData.avail_out < kBufferSize) {
95 if (!dst->write(outputBuffer, kBufferSize - flateData.avail_out))
96 return false;
97 flateData.next_out = outputBuffer;
98 flateData.avail_out = kBufferSize;
99 }
100 }
101
102 if (compress)
103 deflateEnd(&flateData);
104 else
105 inflateEnd(&flateData);
106 if (rc == Z_STREAM_END)
107 return true;
108 return false;
109 }
110
111 }
112
113 // static
Deflate(SkStream * src,SkWStream * dst)114 bool SkFlate::Deflate(SkStream* src, SkWStream* dst) {
115 return doFlate(true, src, dst);
116 }
117
Deflate(const void * ptr,size_t len,SkWStream * dst)118 bool SkFlate::Deflate(const void* ptr, size_t len, SkWStream* dst) {
119 SkMemoryStream stream(ptr, len);
120 return doFlate(true, &stream, dst);
121 }
122
Deflate(const SkData * data,SkWStream * dst)123 bool SkFlate::Deflate(const SkData* data, SkWStream* dst) {
124 if (data) {
125 SkMemoryStream stream(data->data(), data->size());
126 return doFlate(true, &stream, dst);
127 }
128 return false;
129 }
130
131 // static
Inflate(SkStream * src,SkWStream * dst)132 bool SkFlate::Inflate(SkStream* src, SkWStream* dst) {
133 return doFlate(false, src, dst);
134 }
135
136 #endif
137
138