ngx_http_chunked_filter_module.c revision e18a033b
1
2/*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8#include <ngx_config.h>
9#include <ngx_core.h>
10#include <ngx_http.h>
11
12
13typedef struct {
14    ngx_chain_t         *free;
15    ngx_chain_t         *busy;
16} ngx_http_chunked_filter_ctx_t;
17
18
19static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf);
20
21
22static ngx_http_module_t  ngx_http_chunked_filter_module_ctx = {
23    NULL,                                  /* preconfiguration */
24    ngx_http_chunked_filter_init,          /* postconfiguration */
25
26    NULL,                                  /* create main configuration */
27    NULL,                                  /* init main configuration */
28
29    NULL,                                  /* create server configuration */
30    NULL,                                  /* merge server configuration */
31
32    NULL,                                  /* create location configuration */
33    NULL                                   /* merge location configuration */
34};
35
36
37ngx_module_t  ngx_http_chunked_filter_module = {
38    NGX_MODULE_V1,
39    &ngx_http_chunked_filter_module_ctx,   /* module context */
40    NULL,                                  /* module directives */
41    NGX_HTTP_MODULE,                       /* module type */
42    NULL,                                  /* init master */
43    NULL,                                  /* init module */
44    NULL,                                  /* init process */
45    NULL,                                  /* init thread */
46    NULL,                                  /* exit thread */
47    NULL,                                  /* exit process */
48    NULL,                                  /* exit master */
49    NGX_MODULE_V1_PADDING
50};
51
52
53static ngx_http_output_header_filter_pt  ngx_http_next_header_filter;
54static ngx_http_output_body_filter_pt    ngx_http_next_body_filter;
55
56
57static ngx_int_t
58ngx_http_chunked_header_filter(ngx_http_request_t *r)
59{
60    ngx_http_core_loc_conf_t       *clcf;
61    ngx_http_chunked_filter_ctx_t  *ctx;
62
63    if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED
64        || r->headers_out.status == NGX_HTTP_NO_CONTENT
65        || r->headers_out.status < NGX_HTTP_OK
66        || r != r->main
67        || r->method == NGX_HTTP_HEAD)
68    {
69        return ngx_http_next_header_filter(r);
70    }
71
72    if (r->headers_out.content_length_n == -1) {
73        if (r->http_version < NGX_HTTP_VERSION_11) {
74            r->keepalive = 0;
75
76        } else {
77            clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
78
79            if (clcf->chunked_transfer_encoding) {
80                r->chunked = 1;
81
82                ctx = ngx_pcalloc(r->pool,
83                                  sizeof(ngx_http_chunked_filter_ctx_t));
84                if (ctx == NULL) {
85                    return NGX_ERROR;
86                }
87
88                ngx_http_set_ctx(r, ctx, ngx_http_chunked_filter_module);
89
90            } else {
91                r->keepalive = 0;
92            }
93        }
94    }
95
96    return ngx_http_next_header_filter(r);
97}
98
99
100static ngx_int_t
101ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
102{
103    u_char                         *chunk;
104    off_t                           size;
105    ngx_int_t                       rc;
106    ngx_buf_t                      *b;
107    ngx_chain_t                    *out, *cl, *tl, **ll;
108    ngx_http_chunked_filter_ctx_t  *ctx;
109
110    if (in == NULL || !r->chunked || r->header_only) {
111        return ngx_http_next_body_filter(r, in);
112    }
113
114    ctx = ngx_http_get_module_ctx(r, ngx_http_chunked_filter_module);
115
116    out = NULL;
117    ll = &out;
118
119    size = 0;
120    cl = in;
121
122    for ( ;; ) {
123        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
124                       "http chunk: %O", ngx_buf_size(cl->buf));
125
126        size += ngx_buf_size(cl->buf);
127
128        if (cl->buf->flush
129            || cl->buf->sync
130            || ngx_buf_in_memory(cl->buf)
131            || cl->buf->in_file)
132        {
133            tl = ngx_alloc_chain_link(r->pool);
134            if (tl == NULL) {
135                return NGX_ERROR;
136            }
137
138            tl->buf = cl->buf;
139            *ll = tl;
140            ll = &tl->next;
141        }
142
143        if (cl->next == NULL) {
144            break;
145        }
146
147        cl = cl->next;
148    }
149
150    if (size) {
151        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
152        if (tl == NULL) {
153            return NGX_ERROR;
154        }
155
156        b = tl->buf;
157        chunk = b->start;
158
159        if (chunk == NULL) {
160            /* the "0000000000000000" is 64-bit hexadecimal string */
161
162            chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1);
163            if (chunk == NULL) {
164                return NGX_ERROR;
165            }
166
167            b->start = chunk;
168            b->end = chunk + sizeof("0000000000000000" CRLF) - 1;
169        }
170
171        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
172        b->memory = 0;
173        b->temporary = 1;
174        b->pos = chunk;
175        b->last = ngx_sprintf(chunk, "%xO" CRLF, size);
176
177        tl->next = out;
178        out = tl;
179    }
180
181    if (cl->buf->last_buf) {
182        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
183        if (tl == NULL) {
184            return NGX_ERROR;
185        }
186
187        b = tl->buf;
188
189        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
190        b->temporary = 0;
191        b->memory = 1;
192        b->last_buf = 1;
193        b->pos = (u_char *) CRLF "0" CRLF CRLF;
194        b->last = b->pos + 7;
195
196        cl->buf->last_buf = 0;
197
198        *ll = tl;
199
200        if (size == 0) {
201            b->pos += 2;
202        }
203
204    } else if (size > 0) {
205        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
206        if (tl == NULL) {
207            return NGX_ERROR;
208        }
209
210        b = tl->buf;
211
212        b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
213        b->temporary = 0;
214        b->memory = 1;
215        b->pos = (u_char *) CRLF;
216        b->last = b->pos + 2;
217
218        *ll = tl;
219
220    } else {
221        *ll = NULL;
222    }
223
224    rc = ngx_http_next_body_filter(r, out);
225
226    ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out,
227                            (ngx_buf_tag_t) &ngx_http_chunked_filter_module);
228
229    return rc;
230}
231
232
233static ngx_int_t
234ngx_http_chunked_filter_init(ngx_conf_t *cf)
235{
236    ngx_http_next_header_filter = ngx_http_top_header_filter;
237    ngx_http_top_header_filter = ngx_http_chunked_header_filter;
238
239    ngx_http_next_body_filter = ngx_http_top_body_filter;
240    ngx_http_top_body_filter = ngx_http_chunked_body_filter;
241
242    return NGX_OK;
243}
244