1 /*
2     This file is part of libmicrospdy
3     Copyright Copyright (C) 2012 Andrey Uzunov
4 
5     This program is free software: you can redistribute it and/or modify
6     it under the terms of the GNU General Public License as published by
7     the Free Software Foundation, either version 3 of the License, or
8     (at your option) any later version.
9 
10     This program is distributed in the hope that it will be useful,
11     but WITHOUT ANY WARRANTY; without even the implied warranty of
12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13     GNU General Public License for more details.
14 
15     You should have received a copy of the GNU General Public License
16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
17 */
18 
19 /**
20  * @file compression.c
21  * @brief  zlib handling functions
22  * @author Andrey Uzunov
23  */
24 
25 #include "platform.h"
26 #include "structures.h"
27 #include "internal.h"
28 #include "compression.h"
29 
30 /* spdy ver 3 specific dictionary used by zlib */
31 static const unsigned char
32 spdyf_zlib_dictionary[] = {
33 	0x00, 0x00, 0x00, 0x07, 0x6f, 0x70, 0x74, 0x69,   // - - - - o p t i
34 	0x6f, 0x6e, 0x73, 0x00, 0x00, 0x00, 0x04, 0x68,   // o n s - - - - h
35 	0x65, 0x61, 0x64, 0x00, 0x00, 0x00, 0x04, 0x70,   // e a d - - - - p
36 	0x6f, 0x73, 0x74, 0x00, 0x00, 0x00, 0x03, 0x70,   // o s t - - - - p
37 	0x75, 0x74, 0x00, 0x00, 0x00, 0x06, 0x64, 0x65,   // u t - - - - d e
38 	0x6c, 0x65, 0x74, 0x65, 0x00, 0x00, 0x00, 0x05,   // l e t e - - - -
39 	0x74, 0x72, 0x61, 0x63, 0x65, 0x00, 0x00, 0x00,   // t r a c e - - -
40 	0x06, 0x61, 0x63, 0x63, 0x65, 0x70, 0x74, 0x00,   // - a c c e p t -
41 	0x00, 0x00, 0x0e, 0x61, 0x63, 0x63, 0x65, 0x70,   // - - - a c c e p
42 	0x74, 0x2d, 0x63, 0x68, 0x61, 0x72, 0x73, 0x65,   // t - c h a r s e
43 	0x74, 0x00, 0x00, 0x00, 0x0f, 0x61, 0x63, 0x63,   // t - - - - a c c
44 	0x65, 0x70, 0x74, 0x2d, 0x65, 0x6e, 0x63, 0x6f,   // e p t - e n c o
45 	0x64, 0x69, 0x6e, 0x67, 0x00, 0x00, 0x00, 0x0f,   // d i n g - - - -
46 	0x61, 0x63, 0x63, 0x65, 0x70, 0x74, 0x2d, 0x6c,   // a c c e p t - l
47 	0x61, 0x6e, 0x67, 0x75, 0x61, 0x67, 0x65, 0x00,   // a n g u a g e -
48 	0x00, 0x00, 0x0d, 0x61, 0x63, 0x63, 0x65, 0x70,   // - - - a c c e p
49 	0x74, 0x2d, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x73,   // t - r a n g e s
50 	0x00, 0x00, 0x00, 0x03, 0x61, 0x67, 0x65, 0x00,   // - - - - a g e -
51 	0x00, 0x00, 0x05, 0x61, 0x6c, 0x6c, 0x6f, 0x77,   // - - - a l l o w
52 	0x00, 0x00, 0x00, 0x0d, 0x61, 0x75, 0x74, 0x68,   // - - - - a u t h
53 	0x6f, 0x72, 0x69, 0x7a, 0x61, 0x74, 0x69, 0x6f,   // o r i z a t i o
54 	0x6e, 0x00, 0x00, 0x00, 0x0d, 0x63, 0x61, 0x63,   // n - - - - c a c
55 	0x68, 0x65, 0x2d, 0x63, 0x6f, 0x6e, 0x74, 0x72,   // h e - c o n t r
56 	0x6f, 0x6c, 0x00, 0x00, 0x00, 0x0a, 0x63, 0x6f,   // o l - - - - c o
57 	0x6e, 0x6e, 0x65, 0x63, 0x74, 0x69, 0x6f, 0x6e,   // n n e c t i o n
58 	0x00, 0x00, 0x00, 0x0c, 0x63, 0x6f, 0x6e, 0x74,   // - - - - c o n t
59 	0x65, 0x6e, 0x74, 0x2d, 0x62, 0x61, 0x73, 0x65,   // e n t - b a s e
60 	0x00, 0x00, 0x00, 0x10, 0x63, 0x6f, 0x6e, 0x74,   // - - - - c o n t
61 	0x65, 0x6e, 0x74, 0x2d, 0x65, 0x6e, 0x63, 0x6f,   // e n t - e n c o
62 	0x64, 0x69, 0x6e, 0x67, 0x00, 0x00, 0x00, 0x10,   // d i n g - - - -
63 	0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e, 0x74, 0x2d,   // c o n t e n t -
64 	0x6c, 0x61, 0x6e, 0x67, 0x75, 0x61, 0x67, 0x65,   // l a n g u a g e
65 	0x00, 0x00, 0x00, 0x0e, 0x63, 0x6f, 0x6e, 0x74,   // - - - - c o n t
66 	0x65, 0x6e, 0x74, 0x2d, 0x6c, 0x65, 0x6e, 0x67,   // e n t - l e n g
67 	0x74, 0x68, 0x00, 0x00, 0x00, 0x10, 0x63, 0x6f,   // t h - - - - c o
68 	0x6e, 0x74, 0x65, 0x6e, 0x74, 0x2d, 0x6c, 0x6f,   // n t e n t - l o
69 	0x63, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x00, 0x00,   // c a t i o n - -
70 	0x00, 0x0b, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e,   // - - c o n t e n
71 	0x74, 0x2d, 0x6d, 0x64, 0x35, 0x00, 0x00, 0x00,   // t - m d 5 - - -
72 	0x0d, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e, 0x74,   // - c o n t e n t
73 	0x2d, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x00, 0x00,   // - r a n g e - -
74 	0x00, 0x0c, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e,   // - - c o n t e n
75 	0x74, 0x2d, 0x74, 0x79, 0x70, 0x65, 0x00, 0x00,   // t - t y p e - -
76 	0x00, 0x04, 0x64, 0x61, 0x74, 0x65, 0x00, 0x00,   // - - d a t e - -
77 	0x00, 0x04, 0x65, 0x74, 0x61, 0x67, 0x00, 0x00,   // - - e t a g - -
78 	0x00, 0x06, 0x65, 0x78, 0x70, 0x65, 0x63, 0x74,   // - - e x p e c t
79 	0x00, 0x00, 0x00, 0x07, 0x65, 0x78, 0x70, 0x69,   // - - - - e x p i
80 	0x72, 0x65, 0x73, 0x00, 0x00, 0x00, 0x04, 0x66,   // r e s - - - - f
81 	0x72, 0x6f, 0x6d, 0x00, 0x00, 0x00, 0x04, 0x68,   // r o m - - - - h
82 	0x6f, 0x73, 0x74, 0x00, 0x00, 0x00, 0x08, 0x69,   // o s t - - - - i
83 	0x66, 0x2d, 0x6d, 0x61, 0x74, 0x63, 0x68, 0x00,   // f - m a t c h -
84 	0x00, 0x00, 0x11, 0x69, 0x66, 0x2d, 0x6d, 0x6f,   // - - - i f - m o
85 	0x64, 0x69, 0x66, 0x69, 0x65, 0x64, 0x2d, 0x73,   // d i f i e d - s
86 	0x69, 0x6e, 0x63, 0x65, 0x00, 0x00, 0x00, 0x0d,   // i n c e - - - -
87 	0x69, 0x66, 0x2d, 0x6e, 0x6f, 0x6e, 0x65, 0x2d,   // i f - n o n e -
88 	0x6d, 0x61, 0x74, 0x63, 0x68, 0x00, 0x00, 0x00,   // m a t c h - - -
89 	0x08, 0x69, 0x66, 0x2d, 0x72, 0x61, 0x6e, 0x67,   // - i f - r a n g
90 	0x65, 0x00, 0x00, 0x00, 0x13, 0x69, 0x66, 0x2d,   // e - - - - i f -
91 	0x75, 0x6e, 0x6d, 0x6f, 0x64, 0x69, 0x66, 0x69,   // u n m o d i f i
92 	0x65, 0x64, 0x2d, 0x73, 0x69, 0x6e, 0x63, 0x65,   // e d - s i n c e
93 	0x00, 0x00, 0x00, 0x0d, 0x6c, 0x61, 0x73, 0x74,   // - - - - l a s t
94 	0x2d, 0x6d, 0x6f, 0x64, 0x69, 0x66, 0x69, 0x65,   // - m o d i f i e
95 	0x64, 0x00, 0x00, 0x00, 0x08, 0x6c, 0x6f, 0x63,   // d - - - - l o c
96 	0x61, 0x74, 0x69, 0x6f, 0x6e, 0x00, 0x00, 0x00,   // a t i o n - - -
97 	0x0c, 0x6d, 0x61, 0x78, 0x2d, 0x66, 0x6f, 0x72,   // - m a x - f o r
98 	0x77, 0x61, 0x72, 0x64, 0x73, 0x00, 0x00, 0x00,   // w a r d s - - -
99 	0x06, 0x70, 0x72, 0x61, 0x67, 0x6d, 0x61, 0x00,   // - p r a g m a -
100 	0x00, 0x00, 0x12, 0x70, 0x72, 0x6f, 0x78, 0x79,   // - - - p r o x y
101 	0x2d, 0x61, 0x75, 0x74, 0x68, 0x65, 0x6e, 0x74,   // - a u t h e n t
102 	0x69, 0x63, 0x61, 0x74, 0x65, 0x00, 0x00, 0x00,   // i c a t e - - -
103 	0x13, 0x70, 0x72, 0x6f, 0x78, 0x79, 0x2d, 0x61,   // - p r o x y - a
104 	0x75, 0x74, 0x68, 0x6f, 0x72, 0x69, 0x7a, 0x61,   // u t h o r i z a
105 	0x74, 0x69, 0x6f, 0x6e, 0x00, 0x00, 0x00, 0x05,   // t i o n - - - -
106 	0x72, 0x61, 0x6e, 0x67, 0x65, 0x00, 0x00, 0x00,   // r a n g e - - -
107 	0x07, 0x72, 0x65, 0x66, 0x65, 0x72, 0x65, 0x72,   // - r e f e r e r
108 	0x00, 0x00, 0x00, 0x0b, 0x72, 0x65, 0x74, 0x72,   // - - - - r e t r
109 	0x79, 0x2d, 0x61, 0x66, 0x74, 0x65, 0x72, 0x00,   // y - a f t e r -
110 	0x00, 0x00, 0x06, 0x73, 0x65, 0x72, 0x76, 0x65,   // - - - s e r v e
111 	0x72, 0x00, 0x00, 0x00, 0x02, 0x74, 0x65, 0x00,   // r - - - - t e -
112 	0x00, 0x00, 0x07, 0x74, 0x72, 0x61, 0x69, 0x6c,   // - - - t r a i l
113 	0x65, 0x72, 0x00, 0x00, 0x00, 0x11, 0x74, 0x72,   // e r - - - - t r
114 	0x61, 0x6e, 0x73, 0x66, 0x65, 0x72, 0x2d, 0x65,   // a n s f e r - e
115 	0x6e, 0x63, 0x6f, 0x64, 0x69, 0x6e, 0x67, 0x00,   // n c o d i n g -
116 	0x00, 0x00, 0x07, 0x75, 0x70, 0x67, 0x72, 0x61,   // - - - u p g r a
117 	0x64, 0x65, 0x00, 0x00, 0x00, 0x0a, 0x75, 0x73,   // d e - - - - u s
118 	0x65, 0x72, 0x2d, 0x61, 0x67, 0x65, 0x6e, 0x74,   // e r - a g e n t
119 	0x00, 0x00, 0x00, 0x04, 0x76, 0x61, 0x72, 0x79,   // - - - - v a r y
120 	0x00, 0x00, 0x00, 0x03, 0x76, 0x69, 0x61, 0x00,   // - - - - v i a -
121 	0x00, 0x00, 0x07, 0x77, 0x61, 0x72, 0x6e, 0x69,   // - - - w a r n i
122 	0x6e, 0x67, 0x00, 0x00, 0x00, 0x10, 0x77, 0x77,   // n g - - - - w w
123 	0x77, 0x2d, 0x61, 0x75, 0x74, 0x68, 0x65, 0x6e,   // w - a u t h e n
124 	0x74, 0x69, 0x63, 0x61, 0x74, 0x65, 0x00, 0x00,   // t i c a t e - -
125 	0x00, 0x06, 0x6d, 0x65, 0x74, 0x68, 0x6f, 0x64,   // - - m e t h o d
126 	0x00, 0x00, 0x00, 0x03, 0x67, 0x65, 0x74, 0x00,   // - - - - g e t -
127 	0x00, 0x00, 0x06, 0x73, 0x74, 0x61, 0x74, 0x75,   // - - - s t a t u
128 	0x73, 0x00, 0x00, 0x00, 0x06, 0x32, 0x30, 0x30,   // s - - - - 2 0 0
129 	0x20, 0x4f, 0x4b, 0x00, 0x00, 0x00, 0x07, 0x76,   // - O K - - - - v
130 	0x65, 0x72, 0x73, 0x69, 0x6f, 0x6e, 0x00, 0x00,   // e r s i o n - -
131 	0x00, 0x08, 0x48, 0x54, 0x54, 0x50, 0x2f, 0x31,   // - - H T T P - 1
132 	0x2e, 0x31, 0x00, 0x00, 0x00, 0x03, 0x75, 0x72,   // - 1 - - - - u r
133 	0x6c, 0x00, 0x00, 0x00, 0x06, 0x70, 0x75, 0x62,   // l - - - - p u b
134 	0x6c, 0x69, 0x63, 0x00, 0x00, 0x00, 0x0a, 0x73,   // l i c - - - - s
135 	0x65, 0x74, 0x2d, 0x63, 0x6f, 0x6f, 0x6b, 0x69,   // e t - c o o k i
136 	0x65, 0x00, 0x00, 0x00, 0x0a, 0x6b, 0x65, 0x65,   // e - - - - k e e
137 	0x70, 0x2d, 0x61, 0x6c, 0x69, 0x76, 0x65, 0x00,   // p - a l i v e -
138 	0x00, 0x00, 0x06, 0x6f, 0x72, 0x69, 0x67, 0x69,   // - - - o r i g i
139 	0x6e, 0x31, 0x30, 0x30, 0x31, 0x30, 0x31, 0x32,   // n 1 0 0 1 0 1 2
140 	0x30, 0x31, 0x32, 0x30, 0x32, 0x32, 0x30, 0x35,   // 0 1 2 0 2 2 0 5
141 	0x32, 0x30, 0x36, 0x33, 0x30, 0x30, 0x33, 0x30,   // 2 0 6 3 0 0 3 0
142 	0x32, 0x33, 0x30, 0x33, 0x33, 0x30, 0x34, 0x33,   // 2 3 0 3 3 0 4 3
143 	0x30, 0x35, 0x33, 0x30, 0x36, 0x33, 0x30, 0x37,   // 0 5 3 0 6 3 0 7
144 	0x34, 0x30, 0x32, 0x34, 0x30, 0x35, 0x34, 0x30,   // 4 0 2 4 0 5 4 0
145 	0x36, 0x34, 0x30, 0x37, 0x34, 0x30, 0x38, 0x34,   // 6 4 0 7 4 0 8 4
146 	0x30, 0x39, 0x34, 0x31, 0x30, 0x34, 0x31, 0x31,   // 0 9 4 1 0 4 1 1
147 	0x34, 0x31, 0x32, 0x34, 0x31, 0x33, 0x34, 0x31,   // 4 1 2 4 1 3 4 1
148 	0x34, 0x34, 0x31, 0x35, 0x34, 0x31, 0x36, 0x34,   // 4 4 1 5 4 1 6 4
149 	0x31, 0x37, 0x35, 0x30, 0x32, 0x35, 0x30, 0x34,   // 1 7 5 0 2 5 0 4
150 	0x35, 0x30, 0x35, 0x32, 0x30, 0x33, 0x20, 0x4e,   // 5 0 5 2 0 3 - N
151 	0x6f, 0x6e, 0x2d, 0x41, 0x75, 0x74, 0x68, 0x6f,   // o n - A u t h o
152 	0x72, 0x69, 0x74, 0x61, 0x74, 0x69, 0x76, 0x65,   // r i t a t i v e
153 	0x20, 0x49, 0x6e, 0x66, 0x6f, 0x72, 0x6d, 0x61,   // - I n f o r m a
154 	0x74, 0x69, 0x6f, 0x6e, 0x32, 0x30, 0x34, 0x20,   // t i o n 2 0 4 -
155 	0x4e, 0x6f, 0x20, 0x43, 0x6f, 0x6e, 0x74, 0x65,   // N o - C o n t e
156 	0x6e, 0x74, 0x33, 0x30, 0x31, 0x20, 0x4d, 0x6f,   // n t 3 0 1 - M o
157 	0x76, 0x65, 0x64, 0x20, 0x50, 0x65, 0x72, 0x6d,   // v e d - P e r m
158 	0x61, 0x6e, 0x65, 0x6e, 0x74, 0x6c, 0x79, 0x34,   // a n e n t l y 4
159 	0x30, 0x30, 0x20, 0x42, 0x61, 0x64, 0x20, 0x52,   // 0 0 - B a d - R
160 	0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x34, 0x30,   // e q u e s t 4 0
161 	0x31, 0x20, 0x55, 0x6e, 0x61, 0x75, 0x74, 0x68,   // 1 - U n a u t h
162 	0x6f, 0x72, 0x69, 0x7a, 0x65, 0x64, 0x34, 0x30,   // o r i z e d 4 0
163 	0x33, 0x20, 0x46, 0x6f, 0x72, 0x62, 0x69, 0x64,   // 3 - F o r b i d
164 	0x64, 0x65, 0x6e, 0x34, 0x30, 0x34, 0x20, 0x4e,   // d e n 4 0 4 - N
165 	0x6f, 0x74, 0x20, 0x46, 0x6f, 0x75, 0x6e, 0x64,   // o t - F o u n d
166 	0x35, 0x30, 0x30, 0x20, 0x49, 0x6e, 0x74, 0x65,   // 5 0 0 - I n t e
167 	0x72, 0x6e, 0x61, 0x6c, 0x20, 0x53, 0x65, 0x72,   // r n a l - S e r
168 	0x76, 0x65, 0x72, 0x20, 0x45, 0x72, 0x72, 0x6f,   // v e r - E r r o
169 	0x72, 0x35, 0x30, 0x31, 0x20, 0x4e, 0x6f, 0x74,   // r 5 0 1 - N o t
170 	0x20, 0x49, 0x6d, 0x70, 0x6c, 0x65, 0x6d, 0x65,   // - I m p l e m e
171 	0x6e, 0x74, 0x65, 0x64, 0x35, 0x30, 0x33, 0x20,   // n t e d 5 0 3 -
172 	0x53, 0x65, 0x72, 0x76, 0x69, 0x63, 0x65, 0x20,   // S e r v i c e -
173 	0x55, 0x6e, 0x61, 0x76, 0x61, 0x69, 0x6c, 0x61,   // U n a v a i l a
174 	0x62, 0x6c, 0x65, 0x4a, 0x61, 0x6e, 0x20, 0x46,   // b l e J a n - F
175 	0x65, 0x62, 0x20, 0x4d, 0x61, 0x72, 0x20, 0x41,   // e b - M a r - A
176 	0x70, 0x72, 0x20, 0x4d, 0x61, 0x79, 0x20, 0x4a,   // p r - M a y - J
177 	0x75, 0x6e, 0x20, 0x4a, 0x75, 0x6c, 0x20, 0x41,   // u n - J u l - A
178 	0x75, 0x67, 0x20, 0x53, 0x65, 0x70, 0x74, 0x20,   // u g - S e p t -
179 	0x4f, 0x63, 0x74, 0x20, 0x4e, 0x6f, 0x76, 0x20,   // O c t - N o v -
180 	0x44, 0x65, 0x63, 0x20, 0x30, 0x30, 0x3a, 0x30,   // D e c - 0 0 - 0
181 	0x30, 0x3a, 0x30, 0x30, 0x20, 0x4d, 0x6f, 0x6e,   // 0 - 0 0 - M o n
182 	0x2c, 0x20, 0x54, 0x75, 0x65, 0x2c, 0x20, 0x57,   // - - T u e - - W
183 	0x65, 0x64, 0x2c, 0x20, 0x54, 0x68, 0x75, 0x2c,   // e d - - T h u -
184 	0x20, 0x46, 0x72, 0x69, 0x2c, 0x20, 0x53, 0x61,   // - F r i - - S a
185 	0x74, 0x2c, 0x20, 0x53, 0x75, 0x6e, 0x2c, 0x20,   // t - - S u n - -
186 	0x47, 0x4d, 0x54, 0x63, 0x68, 0x75, 0x6e, 0x6b,   // G M T c h u n k
187 	0x65, 0x64, 0x2c, 0x74, 0x65, 0x78, 0x74, 0x2f,   // e d - t e x t -
188 	0x68, 0x74, 0x6d, 0x6c, 0x2c, 0x69, 0x6d, 0x61,   // h t m l - i m a
189 	0x67, 0x65, 0x2f, 0x70, 0x6e, 0x67, 0x2c, 0x69,   // g e - p n g - i
190 	0x6d, 0x61, 0x67, 0x65, 0x2f, 0x6a, 0x70, 0x67,   // m a g e - j p g
191 	0x2c, 0x69, 0x6d, 0x61, 0x67, 0x65, 0x2f, 0x67,   // - i m a g e - g
192 	0x69, 0x66, 0x2c, 0x61, 0x70, 0x70, 0x6c, 0x69,   // i f - a p p l i
193 	0x63, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x2f, 0x78,   // c a t i o n - x
194 	0x6d, 0x6c, 0x2c, 0x61, 0x70, 0x70, 0x6c, 0x69,   // m l - a p p l i
195 	0x63, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x2f, 0x78,   // c a t i o n - x
196 	0x68, 0x74, 0x6d, 0x6c, 0x2b, 0x78, 0x6d, 0x6c,   // h t m l - x m l
197 	0x2c, 0x74, 0x65, 0x78, 0x74, 0x2f, 0x70, 0x6c,   // - t e x t - p l
198 	0x61, 0x69, 0x6e, 0x2c, 0x74, 0x65, 0x78, 0x74,   // a i n - t e x t
199 	0x2f, 0x6a, 0x61, 0x76, 0x61, 0x73, 0x63, 0x72,   // - j a v a s c r
200 	0x69, 0x70, 0x74, 0x2c, 0x70, 0x75, 0x62, 0x6c,   // i p t - p u b l
201 	0x69, 0x63, 0x70, 0x72, 0x69, 0x76, 0x61, 0x74,   // i c p r i v a t
202 	0x65, 0x6d, 0x61, 0x78, 0x2d, 0x61, 0x67, 0x65,   // e m a x - a g e
203 	0x3d, 0x67, 0x7a, 0x69, 0x70, 0x2c, 0x64, 0x65,   // - g z i p - d e
204 	0x66, 0x6c, 0x61, 0x74, 0x65, 0x2c, 0x73, 0x64,   // f l a t e - s d
205 	0x63, 0x68, 0x63, 0x68, 0x61, 0x72, 0x73, 0x65,   // c h c h a r s e
206 	0x74, 0x3d, 0x75, 0x74, 0x66, 0x2d, 0x38, 0x63,   // t - u t f - 8 c
207 	0x68, 0x61, 0x72, 0x73, 0x65, 0x74, 0x3d, 0x69,   // h a r s e t - i
208 	0x73, 0x6f, 0x2d, 0x38, 0x38, 0x35, 0x39, 0x2d,   // s o - 8 8 5 9 -
209 	0x31, 0x2c, 0x75, 0x74, 0x66, 0x2d, 0x2c, 0x2a,   // 1 - u t f - - -
210 	0x2c, 0x65, 0x6e, 0x71, 0x3d, 0x30, 0x2e          // - e n q - 0 -
211 };
212 
213 
214 int
SPDYF_zlib_deflate_init(z_stream * strm)215 SPDYF_zlib_deflate_init(z_stream *strm)
216 {
217 	int ret;
218 
219 	strm->zalloc = Z_NULL;
220 	strm->zfree = Z_NULL;
221 	strm->opaque = Z_NULL;
222 	//the second argument is "level of compression"
223 	//use 0 for no compression; 9 for best compression
224 	ret = deflateInit(strm, Z_DEFAULT_COMPRESSION);
225 	if(ret != Z_OK)
226 	{
227 		SPDYF_DEBUG("deflate init");
228 		return SPDY_NO;
229 	}
230 	ret = deflateSetDictionary(strm,
231 				   spdyf_zlib_dictionary,
232 				   sizeof(spdyf_zlib_dictionary));
233 	if(ret != Z_OK)
234 	{
235 		SPDYF_DEBUG("deflate set dict");
236 		deflateEnd(strm);
237 		return SPDY_NO;
238 	}
239 	return SPDY_YES;
240 }
241 
242 
243 void
SPDYF_zlib_deflate_end(z_stream * strm)244 SPDYF_zlib_deflate_end(z_stream *strm)
245 {
246 	deflateEnd(strm);
247 }
248 
249 int
SPDYF_zlib_deflate(z_stream * strm,const void * src,size_t src_size,size_t * data_used,void ** dest,size_t * dest_size)250 SPDYF_zlib_deflate(z_stream *strm,
251 					const void *src,
252 					size_t src_size,
253 					size_t *data_used,
254 					void **dest,
255 					size_t *dest_size)
256 {
257 	int ret;
258 	int flush;
259 	unsigned int have;
260 	Bytef out[SPDYF_ZLIB_CHUNK];
261 
262 	*dest = NULL;
263 	*dest_size = 0;
264 
265 	do
266 	{
267 		/* check for big data bigger than the buffer used */
268 		if(src_size > SPDYF_ZLIB_CHUNK)
269 		{
270 			strm->avail_in = SPDYF_ZLIB_CHUNK;
271 			src_size -= SPDYF_ZLIB_CHUNK;
272 			/* flush is used for the loop to detect if we still
273 			 * need to supply additional
274 			 * data to the stream via avail_in and next_in. */
275 			flush = Z_NO_FLUSH;
276 		}
277 		else
278 		{
279 			strm->avail_in = src_size;
280 			flush = Z_SYNC_FLUSH;
281 		}
282 		*data_used += strm->avail_in;
283 
284 		strm->next_in = (Bytef *)src;
285 
286 		/* Loop while output data is available */
287 		do
288 		{
289 			strm->avail_out = SPDYF_ZLIB_CHUNK;
290 			strm->next_out = out;
291 
292 			/* No need to check return value of deflate.
293 			* (See zlib documentation at http://www.zlib.net/zlib_how.html */
294 			ret = deflate(strm, flush);
295 			have = SPDYF_ZLIB_CHUNK - strm->avail_out;
296 
297 			/* (Re)allocate memory for dest and keep track of it's size. */
298 			*dest_size += have;
299 			*dest = realloc(*dest, *dest_size);
300 			if(!*dest)
301 			{
302 				SPDYF_DEBUG("realloc data for result");
303 				deflateEnd(strm);
304 				return SPDY_NO;
305 			}
306 			memcpy((*dest) + ((*dest_size) - have), out, have);
307 		}
308 		while(strm->avail_out == 0);
309 		/* At this point, all of the input data should already
310 		* have been used. */
311 		SPDYF_ASSERT(strm->avail_in == 0,"compressing bug");
312 	}
313 	while(flush != Z_SYNC_FLUSH);
314 
315 	return Z_OK == ret ? SPDY_YES : SPDY_NO;
316 }
317 
318 
319 int
SPDYF_zlib_inflate_init(z_stream * strm)320 SPDYF_zlib_inflate_init(z_stream *strm)
321 {
322 	int ret;
323 
324 	strm->zalloc = Z_NULL;
325 	strm->zfree = Z_NULL;
326 	strm->opaque = Z_NULL;
327 	strm->avail_in = 0;
328 	strm->next_in = Z_NULL;
329 	//change 15 to lower value for performance and benchmark
330 	//"The windowBits parameter is the base two logarithm of the
331 	// maximum window size (the size of the history buffer)."
332 	ret = inflateInit2(strm, 15);
333 	if(ret != Z_OK)
334 	{
335 		SPDYF_DEBUG("Cannot inflateInit2 the stream");
336 		return SPDY_NO;
337 	}
338 	return SPDY_YES;
339 }
340 
341 
342 void
SPDYF_zlib_inflate_end(z_stream * strm)343 SPDYF_zlib_inflate_end(z_stream *strm)
344 {
345 	inflateEnd(strm);
346 }
347 
348 
349 int
SPDYF_zlib_inflate(z_stream * strm,const void * src,size_t src_size,void ** dest,size_t * dest_size)350 SPDYF_zlib_inflate(z_stream *strm,
351 					const void *src,
352 					size_t src_size,
353 					void **dest,
354 					size_t *dest_size)
355 {
356 	int ret = Z_OK;
357 	uint32_t have;
358 	Bytef out[SPDYF_ZLIB_CHUNK];
359 
360 	*dest = NULL;
361 	*dest_size = 0;
362 
363 	/* decompress until deflate stream ends or end of file */
364 	do
365 	{
366 		if(src_size > SPDYF_ZLIB_CHUNK)
367 		{
368 			strm->avail_in = SPDYF_ZLIB_CHUNK;
369 			src_size -= SPDYF_ZLIB_CHUNK;
370 		}
371 		else
372 		{
373 			strm->avail_in = src_size;
374 			src_size = 0;
375 		}
376 
377 		if(strm->avail_in == 0){
378 			//the loop breaks always here as the stream never ends
379 			break;
380 		}
381 
382 		strm->next_in = (Bytef *) src;
383 		/* run inflate() on input until output buffer not full */
384 		do {
385 			strm->avail_out = SPDYF_ZLIB_CHUNK;
386 			strm->next_out = out;
387 			ret = inflate(strm, Z_SYNC_FLUSH);
388 
389 			switch (ret)
390 			{
391 				case Z_STREAM_ERROR:
392 					SPDYF_DEBUG("Error on inflate");
393 					//no inflateEnd here, same in zlib example
394 					return SPDY_NO;
395 
396 				case Z_NEED_DICT:
397 					ret = inflateSetDictionary(strm,
398 										   spdyf_zlib_dictionary,
399 										   sizeof(spdyf_zlib_dictionary));
400 					if(ret != Z_OK)
401 					{
402 						SPDYF_DEBUG("Error on inflateSetDictionary");
403 						inflateEnd(strm);
404 						return SPDY_NO;
405 					}
406 					ret = inflate(strm, Z_SYNC_FLUSH);
407 					if(Z_STREAM_ERROR == ret)
408 					{
409 						SPDYF_DEBUG("Error on inflate");
410 						return SPDY_NO;
411 					}
412 					break;
413 
414 				case Z_DATA_ERROR:
415 					SPDYF_DEBUG("Z_DATA_ERROR");
416 					inflateEnd(strm);
417 					return SPDY_NO;
418 
419 				case Z_MEM_ERROR:
420 					SPDYF_DEBUG("Z_MEM_ERROR");
421 					inflateEnd(strm);
422 					return SPDY_NO;
423 			}
424 			have = SPDYF_ZLIB_CHUNK - strm->avail_out;
425 			*dest_size += have;
426 			/* (re)alloc memory for the output buffer */
427 			*dest = realloc(*dest, *dest_size);
428 			if(!*dest)
429 			{
430 				SPDYF_DEBUG("Cannot realloc memory");
431 				inflateEnd(strm);
432 				return SPDY_NO;
433 			}
434 			memcpy((*dest) + ((*dest_size) - have), out, have);
435 		}
436 		while (0 == strm->avail_out);
437 	}
438 	while (Z_STREAM_END != ret);
439 
440 	return Z_OK == ret || Z_STREAM_END == ret ? SPDY_YES : SPDY_NO;
441 }
442