1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23#include "setup.h"
24
25#ifndef CURL_DISABLE_RTSP
26
27#include "urldata.h"
28#include <curl/curl.h>
29#include "transfer.h"
30#include "sendf.h"
31#include "multiif.h"
32#include "http.h"
33#include "url.h"
34#include "progress.h"
35#include "rtsp.h"
36#include "rawstr.h"
37#include "curl_memory.h"
38#include "select.h"
39#include "connect.h"
40
41#define _MPRINTF_REPLACE /* use our functions only */
42#include <curl/mprintf.h>
43
44/* The last #include file should be: */
45#include "memdebug.h"
46
47/*
48 * TODO (general)
49 *  -incoming server requests
50 *      -server CSeq counter
51 *  -digest authentication
52 *  -connect thru proxy
53 *  -pipelining?
54 */
55
56
57#define RTP_PKT_CHANNEL(p)   ((int)((unsigned char)((p)[1])))
58
59#define RTP_PKT_LENGTH(p)  ((((int)((unsigned char)((p)[2]))) << 8) | \
60                             ((int)((unsigned char)((p)[3]))))
61
62/* protocol-specific functions set up to be called by the main engine */
63static CURLcode rtsp_do(struct connectdata *conn, bool *done);
64static CURLcode rtsp_done(struct connectdata *conn, CURLcode, bool premature);
65static CURLcode rtsp_connect(struct connectdata *conn, bool *done);
66static CURLcode rtsp_disconnect(struct connectdata *conn, bool dead);
67
68static int rtsp_getsock_do(struct connectdata *conn,
69                           curl_socket_t *socks,
70                           int numsocks);
71
72/*
73 * Parse and write out any available RTP data.
74 *
75 * nread: amount of data left after k->str. will be modified if RTP
76 *        data is parsed and k->str is moved up
77 * readmore: whether or not the RTP parser needs more data right away
78 */
79static CURLcode rtsp_rtp_readwrite(struct SessionHandle *data,
80                                   struct connectdata *conn,
81                                   ssize_t *nread,
82                                   bool *readmore);
83
84
85/* this returns the socket to wait for in the DO and DOING state for the multi
86   interface and then we're always _sending_ a request and thus we wait for
87   the single socket to become writable only */
88static int rtsp_getsock_do(struct connectdata *conn,
89                           curl_socket_t *socks,
90                           int numsocks)
91{
92  /* write mode */
93  (void)numsocks; /* unused, we trust it to be at least 1 */
94  socks[0] = conn->sock[FIRSTSOCKET];
95  return GETSOCK_WRITESOCK(0);
96}
97
98static
99CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len);
100
101
102/*
103 * RTSP handler interface.
104 */
105const struct Curl_handler Curl_handler_rtsp = {
106  "RTSP",                               /* scheme */
107  ZERO_NULL,                            /* setup_connection */
108  rtsp_do,                              /* do_it */
109  rtsp_done,                            /* done */
110  ZERO_NULL,                            /* do_more */
111  rtsp_connect,                         /* connect_it */
112  ZERO_NULL,                            /* connecting */
113  ZERO_NULL,                            /* doing */
114  ZERO_NULL,                            /* proto_getsock */
115  rtsp_getsock_do,                      /* doing_getsock */
116  ZERO_NULL,                            /* perform_getsock */
117  rtsp_disconnect,                      /* disconnect */
118  rtsp_rtp_readwrite,                   /* readwrite */
119  PORT_RTSP,                            /* defport */
120  CURLPROTO_RTSP,                       /* protocol */
121  PROTOPT_NONE                          /* flags */
122};
123
124/*
125 * The server may send us RTP data at any point, and RTSPREQ_RECEIVE does not
126 * want to block the application forever while receiving a stream. Therefore,
127 * we cannot assume that an RTSP socket is dead just because it is readable.
128 *
129 * Instead, if it is readable, run Curl_getconnectinfo() to peek at the socket
130 * and distinguish between closed and data.
131 */
132bool Curl_rtsp_connisdead(struct connectdata *check)
133{
134  int sval;
135  bool ret_val = TRUE;
136
137  sval = Curl_socket_ready(check->sock[FIRSTSOCKET], CURL_SOCKET_BAD, 0);
138  if(sval == 0) {
139    /* timeout */
140    ret_val = FALSE;
141  }
142  else if(sval & CURL_CSELECT_ERR) {
143    /* socket is in an error state */
144    ret_val = TRUE;
145  }
146  else if((sval & CURL_CSELECT_IN) && check->data) {
147    /* readable with no error. could be closed or could be alive but we can
148       only check if we have a proper SessionHandle for the connection */
149    curl_socket_t connectinfo = Curl_getconnectinfo(check->data, &check);
150    if(connectinfo != CURL_SOCKET_BAD)
151      ret_val = FALSE;
152  }
153
154  return ret_val;
155}
156
157static CURLcode rtsp_connect(struct connectdata *conn, bool *done)
158{
159  CURLcode httpStatus;
160  struct SessionHandle *data = conn->data;
161
162  httpStatus = Curl_http_connect(conn, done);
163
164  /* Initialize the CSeq if not already done */
165  if(data->state.rtsp_next_client_CSeq == 0)
166    data->state.rtsp_next_client_CSeq = 1;
167  if(data->state.rtsp_next_server_CSeq == 0)
168    data->state.rtsp_next_server_CSeq = 1;
169
170  conn->proto.rtspc.rtp_channel = -1;
171
172  return httpStatus;
173}
174
175static CURLcode rtsp_disconnect(struct connectdata *conn, bool dead)
176{
177  (void) dead;
178  Curl_safefree(conn->proto.rtspc.rtp_buf);
179  return CURLE_OK;
180}
181
182
183static CURLcode rtsp_done(struct connectdata *conn,
184                          CURLcode status, bool premature)
185{
186  struct SessionHandle *data = conn->data;
187  struct RTSP *rtsp = data->state.proto.rtsp;
188  CURLcode httpStatus;
189  long CSeq_sent;
190  long CSeq_recv;
191
192  /* Bypass HTTP empty-reply checks on receive */
193  if(data->set.rtspreq == RTSPREQ_RECEIVE)
194    premature = TRUE;
195
196  httpStatus = Curl_http_done(conn, status, premature);
197
198  if(rtsp) {
199    /* Check the sequence numbers */
200    CSeq_sent = rtsp->CSeq_sent;
201    CSeq_recv = rtsp->CSeq_recv;
202    if((data->set.rtspreq != RTSPREQ_RECEIVE) && (CSeq_sent != CSeq_recv)) {
203      failf(data,
204            "The CSeq of this request %ld did not match the response %ld",
205            CSeq_sent, CSeq_recv);
206      return CURLE_RTSP_CSEQ_ERROR;
207    }
208    else if(data->set.rtspreq == RTSPREQ_RECEIVE &&
209            (conn->proto.rtspc.rtp_channel == -1)) {
210      infof(data, "Got an RTP Receive with a CSeq of %ld\n", CSeq_recv);
211      /* TODO CPC: Server -> Client logic here */
212    }
213  }
214
215  return httpStatus;
216}
217
218static CURLcode rtsp_do(struct connectdata *conn, bool *done)
219{
220  struct SessionHandle *data = conn->data;
221  CURLcode result=CURLE_OK;
222  Curl_RtspReq rtspreq = data->set.rtspreq;
223  struct RTSP *rtsp;
224  struct HTTP *http;
225  Curl_send_buffer *req_buffer;
226  curl_off_t postsize = 0; /* for ANNOUNCE and SET_PARAMETER */
227  curl_off_t putsize = 0; /* for ANNOUNCE and SET_PARAMETER */
228
229  const char *p_request = NULL;
230  const char *p_session_id = NULL;
231  const char *p_accept = NULL;
232  const char *p_accept_encoding = NULL;
233  const char *p_range = NULL;
234  const char *p_referrer = NULL;
235  const char *p_stream_uri = NULL;
236  const char *p_transport = NULL;
237  const char *p_uagent = NULL;
238
239  *done = TRUE;
240
241  Curl_reset_reqproto(conn);
242
243  if(!data->state.proto.rtsp) {
244    /* Only allocate this struct if we don't already have it! */
245
246    rtsp = calloc(1, sizeof(struct RTSP));
247    if(!rtsp)
248      return CURLE_OUT_OF_MEMORY;
249    data->state.proto.rtsp = rtsp;
250  }
251  else {
252    rtsp = data->state.proto.rtsp;
253  }
254
255  http = &(rtsp->http_wrapper);
256  /* Assert that no one has changed the RTSP struct in an evil way */
257  DEBUGASSERT((void *)http == (void *)rtsp);
258
259  rtsp->CSeq_sent = data->state.rtsp_next_client_CSeq;
260  rtsp->CSeq_recv = 0;
261
262  /* Setup the 'p_request' pointer to the proper p_request string
263   * Since all RTSP requests are included here, there is no need to
264   * support custom requests like HTTP.
265   **/
266  DEBUGASSERT((rtspreq > RTSPREQ_NONE && rtspreq < RTSPREQ_LAST));
267  data->set.opt_no_body = TRUE; /* most requests don't contain a body */
268  switch(rtspreq) {
269  case RTSPREQ_NONE:
270    failf(data, "Got invalid RTSP request: RTSPREQ_NONE");
271    return CURLE_BAD_FUNCTION_ARGUMENT;
272  case RTSPREQ_OPTIONS:
273    p_request = "OPTIONS";
274    break;
275  case RTSPREQ_DESCRIBE:
276    p_request = "DESCRIBE";
277    data->set.opt_no_body = FALSE;
278    break;
279  case RTSPREQ_ANNOUNCE:
280    p_request = "ANNOUNCE";
281    break;
282  case RTSPREQ_SETUP:
283    p_request = "SETUP";
284    break;
285  case RTSPREQ_PLAY:
286    p_request = "PLAY";
287    break;
288  case RTSPREQ_PAUSE:
289    p_request = "PAUSE";
290    break;
291  case RTSPREQ_TEARDOWN:
292    p_request = "TEARDOWN";
293    break;
294  case RTSPREQ_GET_PARAMETER:
295    /* GET_PARAMETER's no_body status is determined later */
296    p_request = "GET_PARAMETER";
297    break;
298  case RTSPREQ_SET_PARAMETER:
299    p_request = "SET_PARAMETER";
300    break;
301  case RTSPREQ_RECORD:
302    p_request = "RECORD";
303    break;
304  case RTSPREQ_RECEIVE:
305    p_request = "";
306    /* Treat interleaved RTP as body*/
307    data->set.opt_no_body = FALSE;
308    break;
309  case RTSPREQ_LAST:
310    failf(data, "Got invalid RTSP request: RTSPREQ_LAST");
311    return CURLE_BAD_FUNCTION_ARGUMENT;
312  }
313
314  if(rtspreq == RTSPREQ_RECEIVE) {
315    Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE,
316                        &http->readbytecount, -1, NULL);
317
318    return result;
319  }
320
321  p_session_id = data->set.str[STRING_RTSP_SESSION_ID];
322  if(!p_session_id &&
323     (rtspreq & ~(RTSPREQ_OPTIONS | RTSPREQ_DESCRIBE | RTSPREQ_SETUP))) {
324    failf(data, "Refusing to issue an RTSP request [%s] without a session ID.",
325          p_request ? p_request : "");
326    return CURLE_BAD_FUNCTION_ARGUMENT;
327  }
328
329  /* TODO: auth? */
330  /* TODO: proxy? */
331
332  /* Stream URI. Default to server '*' if not specified */
333  if(data->set.str[STRING_RTSP_STREAM_URI]) {
334    p_stream_uri = data->set.str[STRING_RTSP_STREAM_URI];
335  }
336  else {
337    p_stream_uri = "*";
338  }
339
340  /* Transport Header for SETUP requests */
341  p_transport = Curl_checkheaders(data, "Transport:");
342  if(rtspreq == RTSPREQ_SETUP && !p_transport) {
343    /* New Transport: setting? */
344    if(data->set.str[STRING_RTSP_TRANSPORT]) {
345      Curl_safefree(conn->allocptr.rtsp_transport);
346
347      conn->allocptr.rtsp_transport =
348        aprintf("Transport: %s\r\n",
349                data->set.str[STRING_RTSP_TRANSPORT]);
350      if(!conn->allocptr.rtsp_transport)
351        return CURLE_OUT_OF_MEMORY;
352    }
353    else {
354      failf(data,
355            "Refusing to issue an RTSP SETUP without a Transport: header.");
356      return CURLE_BAD_FUNCTION_ARGUMENT;
357    }
358
359    p_transport = conn->allocptr.rtsp_transport;
360  }
361
362  /* Accept Headers for DESCRIBE requests */
363  if(rtspreq == RTSPREQ_DESCRIBE) {
364    /* Accept Header */
365    p_accept = Curl_checkheaders(data, "Accept:")?
366      NULL:"Accept: application/sdp\r\n";
367
368    /* Accept-Encoding header */
369    if(!Curl_checkheaders(data, "Accept-Encoding:") &&
370       data->set.str[STRING_ENCODING]) {
371      Curl_safefree(conn->allocptr.accept_encoding);
372      conn->allocptr.accept_encoding =
373        aprintf("Accept-Encoding: %s\r\n", data->set.str[STRING_ENCODING]);
374
375      if(!conn->allocptr.accept_encoding)
376        return CURLE_OUT_OF_MEMORY;
377
378      p_accept_encoding = conn->allocptr.accept_encoding;
379    }
380  }
381
382  /* The User-Agent string might have been allocated in url.c already, because
383     it might have been used in the proxy connect, but if we have got a header
384     with the user-agent string specified, we erase the previously made string
385     here. */
386  if(Curl_checkheaders(data, "User-Agent:") && conn->allocptr.uagent) {
387    Curl_safefree(conn->allocptr.uagent);
388    conn->allocptr.uagent = NULL;
389  }
390  else if(!Curl_checkheaders(data, "User-Agent:") &&
391          data->set.str[STRING_USERAGENT]) {
392    p_uagent = conn->allocptr.uagent;
393  }
394
395  /* Referrer */
396  Curl_safefree(conn->allocptr.ref);
397  if(data->change.referer && !Curl_checkheaders(data, "Referer:"))
398    conn->allocptr.ref = aprintf("Referer: %s\r\n", data->change.referer);
399  else
400    conn->allocptr.ref = NULL;
401
402  p_referrer = conn->allocptr.ref;
403
404  /*
405   * Range Header
406   * Only applies to PLAY, PAUSE, RECORD
407   *
408   * Go ahead and use the Range stuff supplied for HTTP
409   */
410  if(data->state.use_range &&
411     (rtspreq  & (RTSPREQ_PLAY | RTSPREQ_PAUSE | RTSPREQ_RECORD))) {
412
413    /* Check to see if there is a range set in the custom headers */
414    if(!Curl_checkheaders(data, "Range:") && data->state.range) {
415      Curl_safefree(conn->allocptr.rangeline);
416      conn->allocptr.rangeline = aprintf("Range: %s\r\n", data->state.range);
417      p_range = conn->allocptr.rangeline;
418    }
419  }
420
421  /*
422   * Sanity check the custom headers
423   */
424  if(Curl_checkheaders(data, "CSeq:")) {
425    failf(data, "CSeq cannot be set as a custom header.");
426    return CURLE_RTSP_CSEQ_ERROR;
427  }
428  if(Curl_checkheaders(data, "Session:")) {
429    failf(data, "Session ID cannot be set as a custom header.");
430    return CURLE_BAD_FUNCTION_ARGUMENT;
431  }
432
433  /* Initialize a dynamic send buffer */
434  req_buffer = Curl_add_buffer_init();
435
436  if(!req_buffer)
437    return CURLE_OUT_OF_MEMORY;
438
439  result =
440    Curl_add_bufferf(req_buffer,
441                     "%s %s RTSP/1.0\r\n" /* Request Stream-URI RTSP/1.0 */
442                     "CSeq: %ld\r\n", /* CSeq */
443                     (p_request ? p_request : ""), p_stream_uri,
444                     rtsp->CSeq_sent);
445  if(result)
446    return result;
447
448  /*
449   * Rather than do a normal alloc line, keep the session_id unformatted
450   * to make comparison easier
451   */
452  if(p_session_id) {
453    result = Curl_add_bufferf(req_buffer, "Session: %s\r\n", p_session_id);
454    if(result)
455      return result;
456  }
457
458  /*
459   * Shared HTTP-like options
460   */
461  result = Curl_add_bufferf(req_buffer,
462                            "%s" /* transport */
463                            "%s" /* accept */
464                            "%s" /* accept-encoding */
465                            "%s" /* range */
466                            "%s" /* referrer */
467                            "%s" /* user-agent */
468                            ,
469                            p_transport ? p_transport : "",
470                            p_accept ? p_accept : "",
471                            p_accept_encoding ? p_accept_encoding : "",
472                            p_range ? p_range : "",
473                            p_referrer ? p_referrer : "",
474                            p_uagent ? p_uagent : "");
475  if(result)
476    return result;
477
478  if((rtspreq == RTSPREQ_SETUP) || (rtspreq == RTSPREQ_DESCRIBE)) {
479    result = Curl_add_timecondition(data, req_buffer);
480    if(result)
481      return result;
482  }
483
484  result = Curl_add_custom_headers(conn, req_buffer);
485  if(result)
486    return result;
487
488  if(rtspreq == RTSPREQ_ANNOUNCE ||
489     rtspreq == RTSPREQ_SET_PARAMETER ||
490     rtspreq == RTSPREQ_GET_PARAMETER) {
491
492    if(data->set.upload) {
493      putsize = data->set.infilesize;
494      data->set.httpreq = HTTPREQ_PUT;
495
496    }
497    else {
498      postsize = (data->set.postfieldsize != -1)?
499        data->set.postfieldsize:
500        (data->set.postfields? (curl_off_t)strlen(data->set.postfields):0);
501      data->set.httpreq = HTTPREQ_POST;
502    }
503
504    if(putsize > 0 || postsize > 0) {
505      /* As stated in the http comments, it is probably not wise to
506       * actually set a custom Content-Length in the headers */
507      if(!Curl_checkheaders(data, "Content-Length:")) {
508        result = Curl_add_bufferf(req_buffer,
509            "Content-Length: %" FORMAT_OFF_T"\r\n",
510            (data->set.upload ? putsize : postsize));
511        if(result)
512          return result;
513      }
514
515      if(rtspreq == RTSPREQ_SET_PARAMETER ||
516         rtspreq == RTSPREQ_GET_PARAMETER) {
517        if(!Curl_checkheaders(data, "Content-Type:")) {
518          result = Curl_add_bufferf(req_buffer,
519              "Content-Type: text/parameters\r\n");
520          if(result)
521            return result;
522        }
523      }
524
525      if(rtspreq == RTSPREQ_ANNOUNCE) {
526        if(!Curl_checkheaders(data, "Content-Type:")) {
527          result = Curl_add_bufferf(req_buffer,
528              "Content-Type: application/sdp\r\n");
529          if(result)
530            return result;
531        }
532      }
533
534      data->state.expect100header = FALSE; /* RTSP posts are simple/small */
535    }
536    else if(rtspreq == RTSPREQ_GET_PARAMETER) {
537      /* Check for an empty GET_PARAMETER (heartbeat) request */
538      data->set.httpreq = HTTPREQ_HEAD;
539      data->set.opt_no_body = TRUE;
540    }
541  }
542
543  /* RTSP never allows chunked transfer */
544  data->req.forbidchunk = TRUE;
545  /* Finish the request buffer */
546  result = Curl_add_buffer(req_buffer, "\r\n", 2);
547  if(result)
548    return result;
549
550  if(postsize > 0) {
551    result = Curl_add_buffer(req_buffer, data->set.postfields,
552                             (size_t)postsize);
553    if(result)
554      return result;
555  }
556
557  /* issue the request */
558  result = Curl_add_buffer_send(req_buffer, conn,
559                                &data->info.request_size, 0, FIRSTSOCKET);
560  if(result) {
561    failf(data, "Failed sending RTSP request");
562    return result;
563  }
564
565  Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE, &http->readbytecount,
566                      putsize?FIRSTSOCKET:-1,
567                      putsize?&http->writebytecount:NULL);
568
569  /* Increment the CSeq on success */
570  data->state.rtsp_next_client_CSeq++;
571
572  if(http->writebytecount) {
573    /* if a request-body has been sent off, we make sure this progress is
574       noted properly */
575    Curl_pgrsSetUploadCounter(data, http->writebytecount);
576    if(Curl_pgrsUpdate(conn))
577      result = CURLE_ABORTED_BY_CALLBACK;
578  }
579
580  return result;
581}
582
583
584static CURLcode rtsp_rtp_readwrite(struct SessionHandle *data,
585                                   struct connectdata *conn,
586                                   ssize_t *nread,
587                                   bool *readmore) {
588  struct SingleRequest *k = &data->req;
589  struct rtsp_conn *rtspc = &(conn->proto.rtspc);
590
591  char *rtp; /* moving pointer to rtp data */
592  ssize_t rtp_dataleft; /* how much data left to parse in this round */
593  char *scratch;
594  CURLcode result;
595
596  if(rtspc->rtp_buf) {
597    /* There was some leftover data the last time. Merge buffers */
598    char *newptr = realloc(rtspc->rtp_buf, rtspc->rtp_bufsize + *nread);
599    if(!newptr) {
600      Curl_safefree(rtspc->rtp_buf);
601      rtspc->rtp_buf = NULL;
602      rtspc->rtp_bufsize = 0;
603      return CURLE_OUT_OF_MEMORY;
604    }
605    rtspc->rtp_buf = newptr;
606    memcpy(rtspc->rtp_buf + rtspc->rtp_bufsize, k->str, *nread);
607    rtspc->rtp_bufsize += *nread;
608    rtp = rtspc->rtp_buf;
609    rtp_dataleft = rtspc->rtp_bufsize;
610  }
611  else {
612    /* Just parse the request buffer directly */
613    rtp = k->str;
614    rtp_dataleft = *nread;
615  }
616
617  while((rtp_dataleft > 0) &&
618        (rtp[0] == '$')) {
619    if(rtp_dataleft > 4) {
620      int rtp_length;
621
622      /* Parse the header */
623      /* The channel identifier immediately follows and is 1 byte */
624      rtspc->rtp_channel = RTP_PKT_CHANNEL(rtp);
625
626      /* The length is two bytes */
627      rtp_length = RTP_PKT_LENGTH(rtp);
628
629      if(rtp_dataleft < rtp_length + 4) {
630        /* Need more - incomplete payload*/
631        *readmore = TRUE;
632        break;
633      }
634      else {
635        /* We have the full RTP interleaved packet
636         * Write out the header including the leading '$' */
637        DEBUGF(infof(data, "RTP write channel %d rtp_length %d\n",
638              rtspc->rtp_channel, rtp_length));
639        result = rtp_client_write(conn, &rtp[0], rtp_length + 4);
640        if(result) {
641          failf(data, "Got an error writing an RTP packet");
642          *readmore = FALSE;
643          Curl_safefree(rtspc->rtp_buf);
644          rtspc->rtp_buf = NULL;
645          rtspc->rtp_bufsize = 0;
646          return result;
647        }
648
649        /* Move forward in the buffer */
650        rtp_dataleft -= rtp_length + 4;
651        rtp += rtp_length + 4;
652
653        if(data->set.rtspreq == RTSPREQ_RECEIVE) {
654          /* If we are in a passive receive, give control back
655           * to the app as often as we can.
656           */
657          k->keepon &= ~KEEP_RECV;
658        }
659      }
660    }
661    else {
662      /* Need more - incomplete header */
663      *readmore = TRUE;
664      break;
665    }
666  }
667
668  if(rtp_dataleft != 0 && rtp[0] == '$') {
669    DEBUGF(infof(data, "RTP Rewinding %zu %s\n", rtp_dataleft,
670          *readmore ? "(READMORE)" : ""));
671
672    /* Store the incomplete RTP packet for a "rewind" */
673    scratch = malloc(rtp_dataleft);
674    if(!scratch) {
675      Curl_safefree(rtspc->rtp_buf);
676      rtspc->rtp_buf = NULL;
677      rtspc->rtp_bufsize = 0;
678      return CURLE_OUT_OF_MEMORY;
679    }
680    memcpy(scratch, rtp, rtp_dataleft);
681    Curl_safefree(rtspc->rtp_buf);
682    rtspc->rtp_buf = scratch;
683    rtspc->rtp_bufsize = rtp_dataleft;
684
685    /* As far as the transfer is concerned, this data is consumed */
686    *nread = 0;
687    return CURLE_OK;
688  }
689  else {
690    /* Fix up k->str to point just after the last RTP packet */
691    k->str += *nread - rtp_dataleft;
692
693    /* either all of the data has been read or...
694     * rtp now points at the next byte to parse
695     */
696    if(rtp_dataleft > 0)
697      DEBUGASSERT(k->str[0] == rtp[0]);
698
699    DEBUGASSERT(rtp_dataleft <= *nread); /* sanity check */
700
701    *nread = rtp_dataleft;
702  }
703
704  /* If we get here, we have finished with the leftover/merge buffer */
705  Curl_safefree(rtspc->rtp_buf);
706  rtspc->rtp_buf = NULL;
707  rtspc->rtp_bufsize = 0;
708
709  return CURLE_OK;
710}
711
712static
713CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len)
714{
715  struct SessionHandle *data = conn->data;
716  size_t wrote;
717  curl_write_callback writeit;
718
719  if(len == 0) {
720    failf (data, "Cannot write a 0 size RTP packet.");
721    return CURLE_WRITE_ERROR;
722  }
723
724  writeit = data->set.fwrite_rtp?data->set.fwrite_rtp:data->set.fwrite_func;
725  wrote = writeit(ptr, 1, len, data->set.rtp_out);
726
727  if(CURL_WRITEFUNC_PAUSE == wrote) {
728    failf (data, "Cannot pause RTP");
729    return CURLE_WRITE_ERROR;
730  }
731
732  if(wrote != len) {
733    failf (data, "Failed writing RTP data");
734    return CURLE_WRITE_ERROR;
735  }
736
737  return CURLE_OK;
738}
739
740CURLcode Curl_rtsp_parseheader(struct connectdata *conn,
741                               char *header)
742{
743  struct SessionHandle *data = conn->data;
744  long CSeq = 0;
745
746  if(checkprefix("CSeq:", header)) {
747    /* Store the received CSeq. Match is verified in rtsp_done */
748    int nc;
749    char *temp = strdup(header);
750    if(!temp)
751      return CURLE_OUT_OF_MEMORY;
752    Curl_strntoupper(temp, temp, sizeof(temp));
753    nc = sscanf(temp, "CSEQ: %ld", &CSeq);
754    free(temp);
755    if(nc == 1) {
756      data->state.proto.rtsp->CSeq_recv = CSeq; /* mark the request */
757      data->state.rtsp_CSeq_recv = CSeq; /* update the handle */
758    }
759    else {
760      failf(data, "Unable to read the CSeq header: [%s]", header);
761      return CURLE_RTSP_CSEQ_ERROR;
762    }
763  }
764  else if(checkprefix("Session:", header)) {
765    char *start;
766
767    /* Find the first non-space letter */
768    start = header + 9;
769    while(*start && ISSPACE(*start))
770      start++;
771
772    if(!*start) {
773      failf(data, "Got a blank Session ID");
774    }
775    else if(data->set.str[STRING_RTSP_SESSION_ID]) {
776      /* If the Session ID is set, then compare */
777      if(strncmp(start, data->set.str[STRING_RTSP_SESSION_ID],
778                 strlen(data->set.str[STRING_RTSP_SESSION_ID]))  != 0) {
779        failf(data, "Got RTSP Session ID Line [%s], but wanted ID [%s]",
780              start, data->set.str[STRING_RTSP_SESSION_ID]);
781        return CURLE_RTSP_SESSION_ERROR;
782      }
783    }
784    else {
785      /* If the Session ID is not set, and we find it in a response, then
786         set it */
787
788      /* The session ID can be an alphanumeric or a 'safe' character
789       *
790       * RFC 2326 15.1 Base Syntax:
791       * safe =  "\$" | "-" | "_" | "." | "+"
792       * */
793      char *end = start;
794      while(*end &&
795            (ISALNUM(*end) || *end == '-' || *end == '_' || *end == '.' ||
796             *end == '+' ||
797             (*end == '\\' && *(end + 1) && *(end + 1) == '$' && (++end, 1))))
798        end++;
799
800      /* Copy the id substring into a new buffer */
801      data->set.str[STRING_RTSP_SESSION_ID] = malloc(end - start + 1);
802      if(data->set.str[STRING_RTSP_SESSION_ID] == NULL)
803        return CURLE_OUT_OF_MEMORY;
804      memcpy(data->set.str[STRING_RTSP_SESSION_ID], start, end - start);
805      (data->set.str[STRING_RTSP_SESSION_ID])[end - start] = '\0';
806    }
807  }
808  return CURLE_OK;
809}
810
811#endif /* CURL_DISABLE_RTSP */
812