libavformat/http.c

   1 /*
   2  * HTTP protocol for ffmpeg client
   3  * Copyright (c) 2000, 2001 Fabrice Bellard.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21 #include "avformat.h"
  22 #include <unistd.h>
  23 #include "network.h"
  24
  25 #include "base64.h"
  26
  27 /* XXX: POST protocol is not completly implemented because ffmpeg use
  28    only a subset of it */
  29
  30 //#define DEBUG
  31
  32 /* used for protocol handling */
  33 #define BUFFER_SIZE 1024
  34 #define URL_SIZE    4096
  35 #define MAX_REDIRECTS 8
  36
  37 typedef struct {
  38     URLContext *hd;
  39     unsigned char buffer[BUFFER_SIZE], *buf_ptr, *buf_end;
  40     int line_count;
  41     int http_code;
  42     offset_t off, filesize;
  43     char location[URL_SIZE];
  44 } HTTPContext;
  45
  46 static int http_connect(URLContext *h, const char *path, const char *hoststr,
  47                         const char *auth, int *new_location);
  48 static int http_write(URLContext *h, uint8_t *buf, int size);
  49
  50
  51 /* return non zero if error */
  52 static int http_open_cnx(URLContext *h)
  53 {
  54     const char *path, *proxy_path;
  55     char hostname[1024], hoststr[1024];
  56     char auth[1024];
  57     char path1[1024];
  58     char buf[1024];
  59     int port, use_proxy, err, location_changed = 0, redirects = 0;
  60     HTTPContext *s = h->priv_data;
  61     URLContext *hd = NULL;
  62
  63     proxy_path = getenv("http_proxy");
  64     use_proxy = (proxy_path != NULL) && !getenv("no_proxy") &&
  65         strstart(proxy_path, "http://", NULL);
  66
  67     /* fill the dest addr */
  68  redo:
  69     /* needed in any case to build the host string */
  70     url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port,
  71               path1, sizeof(path1), s->location);
  72     if (port > 0) {
  73         snprintf(hoststr, sizeof(hoststr), "%s:%d", hostname, port);
  74     } else {
  75         pstrcpy(hoststr, sizeof(hoststr), hostname);
  76     }
  77
  78     if (use_proxy) {
  79         url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port,
  80                   NULL, 0, proxy_path);
  81         path = s->location;
  82     } else {
  83         if (path1[0] == '\0')
  84             path = "/";
  85         else
  86             path = path1;
  87     }
  88     if (port < 0)
  89         port = 80;
  90
  91     snprintf(buf, sizeof(buf), "tcp://%s:%d", hostname, port);
  92     err = url_open(&hd, buf, URL_RDWR);
  93     if (err < 0)
  94         goto fail;
  95
  96     s->hd = hd;
  97     if (http_connect(h, path, hoststr, auth, &location_changed) < 0)
  98         goto fail;
  99     if ((s->http_code == 302 || s->http_code == 303) && location_changed == 1) {
 100         /* url moved, get next */
 101         url_close(hd);
 102         if (redirects++ >= MAX_REDIRECTS)
 103             return AVERROR_IO;
 104         location_changed = 0;
 105         goto redo;
 106     }
 107     return 0;
 108  fail:
 109     if (hd)
 110         url_close(hd);
 111     return AVERROR_IO;
 112 }
 113
 114 static int http_open(URLContext *h, const char *uri, int flags)
 115 {
 116     HTTPContext *s;
 117     int ret;
 118
 119     h->is_streamed = 1;
 120
 121     s = av_malloc(sizeof(HTTPContext));
 122     if (!s) {
 123         return AVERROR(ENOMEM);
 124     }
 125     h->priv_data = s;
 126     s->filesize = -1;
 127     s->off = 0;
 128     pstrcpy (s->location, URL_SIZE, uri);
 129
 130     ret = http_open_cnx(h);
 131     if (ret != 0)
 132         av_free (s);
 133     return ret;
 134 }
 135 static int http_getc(HTTPContext *s)
 136 {
 137     int len;
 138     if (s->buf_ptr >= s->buf_end) {
 139         len = url_read(s->hd, s->buffer, BUFFER_SIZE);
 140         if (len < 0) {
 141             return AVERROR_IO;
 142         } else if (len == 0) {
 143             return -1;
 144         } else {
 145             s->buf_ptr = s->buffer;
 146             s->buf_end = s->buffer + len;
 147         }
 148     }
 149     return *s->buf_ptr++;
 150 }
 151
 152 static int process_line(URLContext *h, char *line, int line_count,
 153                         int *new_location)
 154 {
 155     HTTPContext *s = h->priv_data;
 156     char *tag, *p;
 157
 158     /* end of header */
 159     if (line[0] == '\0')
 160         return 0;
 161
 162     p = line;
 163     if (line_count == 0) {
 164         while (!isspace(*p) && *p != '\0')
 165             p++;
 166         while (isspace(*p))
 167             p++;
 168         s->http_code = strtol(p, NULL, 10);
 169 #ifdef DEBUG
 170         printf("http_code=%d\n", s->http_code);
 171 #endif
 172         /* error codes are 4xx and 5xx */
 173         if (s->http_code >= 400 && s->http_code < 600)
 174             return -1;
 175     } else {
 176         while (*p != '\0' && *p != ':')
 177             p++;
 178         if (*p != ':')
 179             return 1;
 180
 181         *p = '\0';
 182         tag = line;
 183         p++;
 184         while (isspace(*p))
 185             p++;
 186         if (!strcmp(tag, "Location")) {
 187             strcpy(s->location, p);
 188             *new_location = 1;
 189         } else if (!strcmp (tag, "Content-Length") && s->filesize == -1) {
 190             s->filesize = atoll(p);
 191         } else if (!strcmp (tag, "Content-Range")) {
 192             /* "bytes $from-$to/$document_size" */
 193             const char *slash;
 194             if (!strncmp (p, "bytes ", 6)) {
 195                 p += 6;
 196                 s->off = atoll(p);
 197                 if ((slash = strchr(p, '/')) && strlen(slash) > 0)
 198                     s->filesize = atoll(slash+1);
 199             }
 200             h->is_streamed = 0; /* we _can_ in fact seek */
 201         }
 202     }
 203     return 1;
 204 }
 205
 206 static int http_connect(URLContext *h, const char *path, const char *hoststr,
 207                         const char *auth, int *new_location)
 208 {
 209     HTTPContext *s = h->priv_data;
 210     int post, err, ch;
 211     char line[1024], *q;
 212     char *auth_b64;
 213     offset_t off = s->off;
 214
 215
 216     /* send http header */
 217     post = h->flags & URL_WRONLY;
 218
 219     auth_b64 = av_base64_encode((uint8_t *)auth, strlen(auth));
 220     snprintf(s->buffer, sizeof(s->buffer),
 221              "%s %s HTTP/1.1\r\n"
 222              "User-Agent: %s\r\n"
 223              "Accept: */*\r\n"
 224              "Range: bytes=%"PRId64"-\r\n"
 225              "Host: %s\r\n"
 226              "Authorization: Basic %s\r\n"
 227              "Connection: close\r\n"
 228              "\r\n",
 229              post ? "POST" : "GET",
 230              path,
 231              LIBAVFORMAT_IDENT,
 232              s->off,
 233              hoststr,
 234              auth_b64);
 235
 236     av_freep(&auth_b64);
 237     if (http_write(h, s->buffer, strlen(s->buffer)) < 0)
 238         return AVERROR_IO;
 239
 240     /* init input buffer */
 241     s->buf_ptr = s->buffer;
 242     s->buf_end = s->buffer;
 243     s->line_count = 0;
 244     s->off = 0;
 245     s->filesize = -1;
 246     if (post) {
 247         sleep(1);
 248         return 0;
 249     }
 250
 251     /* wait for header */
 252     q = line;
 253     for(;;) {
 254         ch = http_getc(s);
 255         if (ch < 0)
 256             return AVERROR_IO;
 257         if (ch == '\n') {
 258             /* process line */
 259             if (q > line && q[-1] == '\r')
 260                 q--;
 261             *q = '\0';
 262 #ifdef DEBUG
 263             printf("header='%s'\n", line);
 264 #endif
 265             err = process_line(h, line, s->line_count, new_location);
 266             if (err < 0)
 267                 return err;
 268             if (err == 0)
 269                 break;
 270             s->line_count++;
 271             q = line;
 272         } else {
 273             if ((q - line) < sizeof(line) - 1)
 274                 *q++ = ch;
 275         }
 276     }
 277
 278     return (off == s->off) ? 0 : -1;
 279 }
 280
 281
 282 static int http_read(URLContext *h, uint8_t *buf, int size)
 283 {
 284     HTTPContext *s = h->priv_data;
 285     int len;
 286
 287     /* read bytes from input buffer first */
 288     len = s->buf_end - s->buf_ptr;
 289     if (len > 0) {
 290         if (len > size)
 291             len = size;
 292         memcpy(buf, s->buf_ptr, len);
 293         s->buf_ptr += len;
 294     } else {
 295         len = url_read(s->hd, buf, size);
 296     }
 297     if (len > 0)
 298         s->off += len;
 299     return len;
 300 }
 301
 302 /* used only when posting data */
 303 static int http_write(URLContext *h, uint8_t *buf, int size)
 304 {
 305     HTTPContext *s = h->priv_data;
 306     return url_write(s->hd, buf, size);
 307 }
 308
 309 static int http_close(URLContext *h)
 310 {
 311     HTTPContext *s = h->priv_data;
 312     url_close(s->hd);
 313     av_free(s);
 314     return 0;
 315 }
 316
 317 static offset_t http_seek(URLContext *h, offset_t off, int whence)
 318 {
 319     HTTPContext *s = h->priv_data;
 320     URLContext *old_hd = s->hd;
 321     offset_t old_off = s->off;
 322
 323     if (whence == AVSEEK_SIZE)
 324         return s->filesize;
 325     else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed)
 326         return -1;
 327
 328     /* we save the old context in case the seek fails */
 329     s->hd = NULL;
 330     if (whence == SEEK_CUR)
 331         off += s->off;
 332     else if (whence == SEEK_END)
 333         off += s->filesize;
 334     s->off = off;
 335
 336     /* if it fails, continue on old connection */
 337     if (http_open_cnx(h) < 0) {
 338         s->hd = old_hd;
 339         s->off = old_off;
 340         return -1;
 341     }
 342     url_close(old_hd);
 343     return off;
 344 }
 345
 346 URLProtocol http_protocol = {
 347     "http",
 348     http_open,
 349     http_read,
 350     http_write,
 351     http_seek,
 352     http_close,
 353 };