1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/*
* QEMU VNC display driver: zlib encoding
*
* Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>
* Copyright (C) 2006 Fabrice Bellard
* Copyright (C) 2009 Red Hat, Inc
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "vnc.h"
#define ZALLOC_ALIGNMENT 16
static void *zalloc(void *x, unsigned items, unsigned size)
{
void *p;
size *= items;
size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
p = qemu_mallocz(size);
return (p);
}
static void zfree(void *x, void *addr)
{
qemu_free(addr);
}
static void vnc_zlib_start(VncState *vs)
{
buffer_reset(&vs->zlib);
// make the output buffer be the zlib buffer, so we can compress it later
vs->zlib_tmp = vs->output;
vs->output = vs->zlib;
}
static int vnc_zlib_stop(VncState *vs)
{
z_streamp zstream = &vs->zlib_stream;
int previous_out;
// switch back to normal output/zlib buffers
vs->zlib = vs->output;
vs->output = vs->zlib_tmp;
// compress the zlib buffer
// initialize the stream
// XXX need one stream per session
if (zstream->opaque != vs) {
int err;
VNC_DEBUG("VNC: initializing zlib stream\n");
VNC_DEBUG("VNC: opaque = %p | vs = %p\n", zstream->opaque, vs);
zstream->zalloc = zalloc;
zstream->zfree = zfree;
err = deflateInit2(zstream, vs->tight_compression, Z_DEFLATED, MAX_WBITS,
MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
if (err != Z_OK) {
fprintf(stderr, "VNC: error initializing zlib\n");
return -1;
}
vs->zlib_level = vs->tight_compression;
zstream->opaque = vs;
}
if (vs->tight_compression != vs->zlib_level) {
if (deflateParams(zstream, vs->tight_compression,
Z_DEFAULT_STRATEGY) != Z_OK) {
return -1;
}
vs->zlib_level = vs->tight_compression;
}
// reserve memory in output buffer
buffer_reserve(&vs->output, vs->zlib.offset + 64);
// set pointers
zstream->next_in = vs->zlib.buffer;
zstream->avail_in = vs->zlib.offset;
zstream->next_out = vs->output.buffer + vs->output.offset;
zstream->avail_out = vs->output.capacity - vs->output.offset;
zstream->data_type = Z_BINARY;
previous_out = zstream->total_out;
// start encoding
if (deflate(zstream, Z_SYNC_FLUSH) != Z_OK) {
fprintf(stderr, "VNC: error during zlib compression\n");
return -1;
}
vs->output.offset = vs->output.capacity - zstream->avail_out;
return zstream->total_out - previous_out;
}
int vnc_zlib_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
{
int old_offset, new_offset, bytes_written;
vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_ZLIB);
// remember where we put in the follow-up size
old_offset = vs->output.offset;
vnc_write_s32(vs, 0);
// compress the stream
vnc_zlib_start(vs);
vnc_raw_send_framebuffer_update(vs, x, y, w, h);
bytes_written = vnc_zlib_stop(vs);
if (bytes_written == -1)
return 0;
// hack in the size
new_offset = vs->output.offset;
vs->output.offset = old_offset;
vnc_write_u32(vs, bytes_written);
vs->output.offset = new_offset;
return 1;
}
void vnc_zlib_clear(VncState *vs)
{
if (vs->zlib_stream.opaque) {
deflateEnd(&vs->zlib_stream);
}
buffer_free(&vs->zlib);
}
|
