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                         line_len++;
  87                 }
  88
  89                 *newline = 0;
  90                 if (newline == buf) {
  91                         r->header_cb = NULL;
  92                         if (r->header_end)
  93                                 r->header_end(r);
  94                         break;
  95                 }
  96
  97                 val = uh_split_header(buf);
  98                 if (!val) {
  99                         relay_error(r);
 100                         return;
 101                 }
 102
 103                 r->header_cb(r, buf, val);
 104                 ustream_consume(s, line_len);
 105         }
 106 }
 107
 108 static void relay_read_cb(struct ustream *s, int bytes)
 109 {
 110         struct relay *r = container_of(s, struct relay, sfd.stream);
 111         struct client *cl = r->cl;
 112         struct ustream *us = cl->us;
 113         char *buf;
 114         int len;
 115
 116         relay_process_headers(r);
 117
 118         if (r->header_cb) {
 119                 /*
 120                  * if eof, ensure that remaining data is discarded, so the
 121                  * state change cb will tear down the stream
 122                  */
 123                 if (s->eof)
 124                         relay_error(r);
 125                 return;
 126         }
 127
 128         if (!s->eof && ustream_pending_data(us, true)) {
 129                 ustream_set_read_blocked(s, true);
 130                 return;
 131         }
 132
 133         buf = ustream_get_read_buf(s, &len);
 134         uh_chunk_write(cl, buf, len);
 135         ustream_consume(s, len);
 136 }
 137
 138 static void relay_close_if_done(struct relay *r)
 139 {
 140         struct ustream *s = &r->sfd.stream;
 141
 142         if (!s->eof || ustream_pending_data(s, false))
 143                 return;
 144
 145         uh_relay_close(r, r->ret);
 146 }
 147
 148 static void relay_state_cb(struct ustream *s)
 149 {
 150         struct relay *r = container_of(s, struct relay, sfd.stream);
 151
 152         if (r->process_done)
 153                 relay_close_if_done(r);
 154 }
 155
 156 static void relay_proc_cb(struct uloop_process *proc, int ret)
 157 {
 158         struct relay *r = container_of(proc, struct relay, proc);
 159
 160         r->process_done = true;
 161         r->ret = ret;
 162         relay_close_if_done(r);
 163 }
 164
 165 void uh_relay_open(struct client *cl, struct relay *r, int fd, int pid)
 166 {
 167         struct ustream *us = &r->sfd.stream;
 168
 169         r->cl = cl;
 170         ustream_fd_init(&r->sfd, fd);
 171         us->notify_read = relay_read_cb;
 172         us->notify_state = relay_state_cb;
 173         us->string_data = true;
 174
 175         r->proc.pid = pid;
 176         r->proc.cb = relay_proc_cb;
 177         uloop_process_add(&r->proc);
 178 }