Mercurial > hg > nginx
annotate src/http/modules/ngx_http_empty_gif_module.c @ 8078:5244d3b165ff
SSL: single allocation in session cache on 32-bit platforms.
Given the present typical SSL session sizes, on 32-bit platforms it is
now beneficial to store all data in a single allocation, since rbtree
node + session id + ASN1 representation of a session takes 256 bytes of
shared memory (36 + 32 + 150 = about 218 bytes plus SNI server name).
Storing all data in a single allocation is beneficial for SNI names up to
about 40 characters long and makes it possible to store about 4000 sessions
in one megabyte (instead of about 3000 sessions now). This also slightly
simplifies the code.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 12 Oct 2022 20:14:40 +0300 |
parents | d620f497c50f |
children |
rev | line source |
---|---|
577 | 1 |
2 /* | |
3 * Copyright (C) Igor Sysoev | |
4412 | 4 * Copyright (C) Nginx, Inc. |
577 | 5 */ |
6 | |
7 #include <ngx_config.h> | |
8 #include <ngx_core.h> | |
9 #include <ngx_http.h> | |
10 | |
11 | |
12 static char *ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t *cmd, | |
13 void *conf); | |
14 | |
15 static ngx_command_t ngx_http_empty_gif_commands[] = { | |
16 | |
17 { ngx_string("empty_gif"), | |
18 NGX_HTTP_LOC_CONF|NGX_CONF_NOARGS, | |
19 ngx_http_empty_gif, | |
20 0, | |
21 0, | |
22 NULL }, | |
23 | |
24 ngx_null_command | |
25 }; | |
26 | |
27 | |
28 /* the minimal single pixel transparent GIF, 43 bytes */ | |
29 | |
30 static u_char ngx_empty_gif[] = { | |
31 | |
581 | 32 'G', 'I', 'F', '8', '9', 'a', /* header */ |
577 | 33 |
581 | 34 /* logical screen descriptor */ |
35 0x01, 0x00, /* logical screen width */ | |
36 0x01, 0x00, /* logical screen height */ | |
37 0x80, /* global 1-bit color table */ | |
38 0x01, /* background color #1 */ | |
39 0x00, /* no aspect ratio */ | |
577 | 40 |
581 | 41 /* global color table */ |
42 0x00, 0x00, 0x00, /* #0: black */ | |
43 0xff, 0xff, 0xff, /* #1: white */ | |
577 | 44 |
581 | 45 /* graphic control extension */ |
46 0x21, /* extension introducer */ | |
47 0xf9, /* graphic control label */ | |
48 0x04, /* block size */ | |
49 0x01, /* transparent color is given, */ | |
50 /* no disposal specified, */ | |
51 /* user input is not expected */ | |
52 0x00, 0x00, /* delay time */ | |
53 0x01, /* transparent color #1 */ | |
54 0x00, /* block terminator */ | |
577 | 55 |
581 | 56 /* image descriptor */ |
57 0x2c, /* image separator */ | |
58 0x00, 0x00, /* image left position */ | |
59 0x00, 0x00, /* image top position */ | |
60 0x01, 0x00, /* image width */ | |
61 0x01, 0x00, /* image height */ | |
62 0x00, /* no local color table, no interlaced */ | |
577 | 63 |
581 | 64 /* table based image data */ |
65 0x02, /* LZW minimum code size, */ | |
66 /* must be at least 2-bit */ | |
67 0x02, /* block size */ | |
577 | 68 0x4c, 0x01, /* compressed bytes 01_001_100, 0000000_1 */ |
581 | 69 /* 100: clear code */ |
70 /* 001: 1 */ | |
71 /* 101: end of information code */ | |
72 0x00, /* block terminator */ | |
577 | 73 |
581 | 74 0x3B /* trailer */ |
577 | 75 }; |
76 | |
77 | |
667 | 78 static ngx_http_module_t ngx_http_empty_gif_module_ctx = { |
577 | 79 NULL, /* preconfiguration */ |
80 NULL, /* postconfiguration */ | |
81 | |
82 NULL, /* create main configuration */ | |
83 NULL, /* init main configuration */ | |
84 | |
85 NULL, /* create server configuration */ | |
86 NULL, /* merge server configuration */ | |
87 | |
88 NULL, /* create location configuration */ | |
89 NULL /* merge location configuration */ | |
90 }; | |
91 | |
92 | |
93 ngx_module_t ngx_http_empty_gif_module = { | |
94 NGX_MODULE_V1, | |
95 &ngx_http_empty_gif_module_ctx, /* module context */ | |
96 ngx_http_empty_gif_commands, /* module directives */ | |
97 NGX_HTTP_MODULE, /* module type */ | |
98 NULL, /* init master */ | |
99 NULL, /* init module */ | |
100 NULL, /* init process */ | |
101 NULL, /* init thread */ | |
102 NULL, /* exit thread */ | |
103 NULL, /* exit process */ | |
104 NULL, /* exit master */ | |
105 NGX_MODULE_V1_PADDING | |
106 }; | |
107 | |
108 | |
3635
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
109 static ngx_str_t ngx_http_gif_type = ngx_string("image/gif"); |
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
110 |
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
111 |
577 | 112 static ngx_int_t |
113 ngx_http_empty_gif_handler(ngx_http_request_t *r) | |
114 { | |
3635
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
115 ngx_http_complex_value_t cv; |
577 | 116 |
645 | 117 if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) { |
577 | 118 return NGX_HTTP_NOT_ALLOWED; |
119 } | |
120 | |
3635
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
121 ngx_memzero(&cv, sizeof(ngx_http_complex_value_t)); |
577 | 122 |
3635
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
123 cv.value.len = sizeof(ngx_empty_gif); |
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
124 cv.value.data = ngx_empty_gif; |
577 | 125 r->headers_out.last_modified_time = 23349600; |
126 | |
3635
c0113b6648de
use ngx_http_send_response() in empty_gif
Igor Sysoev <igor@sysoev.ru>
parents:
3516
diff
changeset
|
127 return ngx_http_send_response(r, NGX_HTTP_OK, &ngx_http_gif_type, &cv); |
577 | 128 } |
129 | |
130 | |
131 static char * | |
132 ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) | |
133 { | |
134 ngx_http_core_loc_conf_t *clcf; | |
135 | |
136 clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module); | |
137 clcf->handler = ngx_http_empty_gif_handler; | |
138 | |
139 return NGX_CONF_OK; | |
140 } |