59cdaa5904883d7db93a1b2ac64628110bfaaabb
[project/uhttpd.git] / relay.c
1 /*
2  * uhttpd - Tiny single-threaded httpd
3  *
4  *   Copyright (C) 2010-2012 Jo-Philipp Wich <xm@subsignal.org>
5  *   Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
6  *
7  *  Licensed under the Apache License, Version 2.0 (the "License");
8  *  you may not use this file except in compliance with the License.
9  *  You may obtain a copy of the License at
10  *
11  *      http://www.apache.org/licenses/LICENSE-2.0
12  *
13  *  Unless required by applicable law or agreed to in writing, software
14  *  distributed under the License is distributed on an "AS IS" BASIS,
15  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  *  See the License for the specific language governing permissions and
17  *  limitations under the License.
18  */
19
20 #include <signal.h>
21 #include "uhttpd.h"
22
23 void uh_relay_free(struct relay *r)
24 {
25         if (!r->cl)
26                 return;
27
28         if (r->proc.pending)
29                 kill(r->proc.pid, SIGKILL);
30
31         uloop_process_delete(&r->proc);
32         ustream_free(&r->sfd.stream);
33         close(r->sfd.fd.fd);
34
35         r->cl = NULL;
36 }
37
38 void uh_relay_close(struct relay *r, int ret)
39 {
40         struct ustream *us = &r->sfd.stream;
41
42         if (!us->notify_read)
43                 return;
44
45         us->notify_read = NULL;
46         us->notify_write = NULL;
47         us->notify_state = NULL;
48
49         if (r->close)
50                 r->close(r, ret);
51 }
52
53 static void relay_error(struct relay *r)
54 {
55         struct ustream *s = &r->sfd.stream;
56         int len;
57
58         s->eof = true;
59         ustream_get_read_buf(s, &len);
60         if (len)
61                 ustream_consume(s, len);
62         ustream_state_change(s);
63 }
64
65 static void relay_process_headers(struct relay *r)
66 {
67         struct ustream *s = &r->sfd.stream;
68         char *buf, *newline;
69         int len;
70
71         if (!r->header_cb)
72                 return;
73
74         while (r->header_cb) {
75                 int line_len;
76                 char *val;
77
78                 buf = ustream_get_read_buf(s, &len);
79                 newline = strchr(buf, '\n');
80                 if (!newline)
81                         break;
82
83                 line_len = newline + 1 - buf;
84                 if (newline > buf && newline[-1] == '\r')
85                         newline--;
86
87                 *newline = 0;
88                 if (newline == buf) {
89                         r->header_cb = NULL;
90                         if (r->header_end)
91                                 r->header_end(r);
92                         break;
93                 }
94
95                 val = uh_split_header(buf);
96                 if (!val) {
97                         relay_error(r);
98                         return;
99                 }
100
101                 r->header_cb(r, buf, val);
102                 ustream_consume(s, line_len);
103         }
104 }
105
106 static void relay_read_cb(struct ustream *s, int bytes)
107 {
108         struct relay *r = container_of(s, struct relay, sfd.stream);
109         struct client *cl = r->cl;
110         struct ustream *us = cl->us;
111         char *buf;
112         int len;
113
114         relay_process_headers(r);
115
116         if (r->header_cb) {
117                 /*
118                  * if eof, ensure that remaining data is discarded, so the
119                  * state change cb will tear down the stream
120                  */
121                 if (s->eof)
122                         relay_error(r);
123                 return;
124         }
125
126         if (!s->eof && ustream_pending_data(us, true)) {
127                 ustream_set_read_blocked(s, true);
128                 return;
129         }
130
131         buf = ustream_get_read_buf(s, &len);
132         uh_chunk_write(cl, buf, len);
133         ustream_consume(s, len);
134 }
135
136 static void relay_close_if_done(struct relay *r)
137 {
138         struct ustream *s = &r->sfd.stream;
139
140         if (!s->eof || ustream_pending_data(s, false))
141                 return;
142
143         uh_relay_close(r, r->ret);
144 }
145
146 static void relay_state_cb(struct ustream *s)
147 {
148         struct relay *r = container_of(s, struct relay, sfd.stream);
149
150         if (r->process_done)
151                 relay_close_if_done(r);
152 }
153
154 static void relay_proc_cb(struct uloop_process *proc, int ret)
155 {
156         struct relay *r = container_of(proc, struct relay, proc);
157
158         r->process_done = true;
159         r->ret = ret;
160         relay_close_if_done(r);
161 }
162
163 void uh_relay_open(struct client *cl, struct relay *r, int fd, int pid)
164 {
165         struct ustream *us = &r->sfd.stream;
166
167         r->cl = cl;
168         ustream_fd_init(&r->sfd, fd);
169         us->notify_read = relay_read_cb;
170         us->notify_state = relay_state_cb;
171         us->string_data = true;
172
173         r->proc.pid = pid;
174         r->proc.cb = relay_proc_cb;
175         uloop_process_add(&r->proc);
176 }