Use av_log(.., AV_LOG_ERROR) instead of dprintf() for logging errors. This
[ffmpeg.git] / libavformat / mmst.c
1 /*
2  * MMS protocol over TCP
3  * Copyright (c) 2006,2007 Ryan Martell
4  * Copyright (c) 2007 Bj√∂rn Axelsson
5  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23
24 /* References
25  * MMS protocol specification:
26  *  [1]http://msdn.microsoft.com/en-us/library/cc234711(PROT.10).aspx
27  * ASF specification. Revision 01.20.03.
28  *  [2]http://msdn.microsoft.com/en-us/library/bb643323.aspx
29  */
30
31 #include "avformat.h"
32 #include "internal.h"
33 #include "libavutil/intreadwrite.h"
34 #include "libavcodec/bytestream.h"
35 #include "network.h"
36 #include "asf.h"
37
38 #define LOCAL_ADDRESS 0xc0a80081    // FIXME get and use correct local ip address.
39 #define LOCAL_PORT    1037          // as above.
40 /** Client to server packet types. */
41 typedef enum {
42     CS_PKT_INITIAL                  = 0x01,
43     CS_PKT_PROTOCOL_SELECT          = 0x02,
44     CS_PKT_MEDIA_FILE_REQUEST       = 0x05,
45     CS_PKT_START_FROM_PKT_ID        = 0x07,
46     CS_PKT_STREAM_PAUSE             = 0x09,
47     CS_PKT_STREAM_CLOSE             = 0x0d,
48     CS_PKT_MEDIA_HEADER_REQUEST     = 0x15,
49     CS_PKT_TIMING_DATA_REQUEST      = 0x18,
50     CS_PKT_USER_PASSWORD            = 0x1a,
51     CS_PKT_KEEPALIVE                = 0x1b,
52     CS_PKT_STREAM_ID_REQUEST        = 0x33,
53 } MMSCSPacketType;
54
55 /** Server to client packet types. */
56 typedef enum {
57     /** Control packets. */
58     /*@{*/
59     SC_PKT_CLIENT_ACCEPTED          = 0x01,
60     SC_PKT_PROTOCOL_ACCEPTED        = 0x02,
61     SC_PKT_PROTOCOL_FAILED          = 0x03,
62     SC_PKT_MEDIA_PKT_FOLLOWS        = 0x05,
63     SC_PKT_MEDIA_FILE_DETAILS       = 0x06,
64     SC_PKT_HEADER_REQUEST_ACCEPTED  = 0x11,
65     SC_PKT_TIMING_TEST_REPLY        = 0x15,
66     SC_PKT_PASSWORD_REQUIRED        = 0x1a,
67     SC_PKT_KEEPALIVE                = 0x1b,
68     SC_PKT_STREAM_STOPPED           = 0x1e,
69     SC_PKT_STREAM_CHANGING          = 0x20,
70     SC_PKT_STREAM_ID_ACCEPTED       = 0x21,
71     /*@}*/
72
73     /** Pseudo packets. */
74     /*@{*/
75     SC_PKT_CANCEL                   = -1,
76     SC_PKT_NO_DATA                  = -2,
77     /*@}*/
78
79     /** Data packets. */
80     /*@{*/
81     SC_PKT_ASF_HEADER               = 0x010000,// make it bigger than 0xFF in case of
82     SC_PKT_ASF_MEDIA                = 0x010001,// receiving false data packets.
83     /*@}*/
84 } MMSSCPacketType;
85
86 typedef struct {
87     int id;
88 }MMSStream;
89
90 typedef struct {
91     int outgoing_packet_seq;             ///< Outgoing packet sequence number.
92     char path[256];                      ///< Path of the resource being asked for.
93     char host[128];                      ///< Host of the resources.
94
95     URLContext *mms_hd;                  ///< TCP connection handle
96     MMSStream streams[MAX_STREAMS];
97
98     /** Buffer for outgoing packets. */
99     /*@{*/
100     uint8_t *write_out_ptr;              ///< Pointer for writting the buffer.
101     uint8_t out_buffer[512];             ///< Buffer for outgoing packet.
102     /*@}*/
103
104     /** Buffer for incoming packets. */
105     /*@{*/
106     uint8_t in_buffer[8192];             ///< Buffer for incoming packets.
107     uint8_t *read_in_ptr;                ///< Pointer for reading from incoming buffer.
108     int remaining_in_len;                ///< Reading length from incoming buffer.
109     /*@}*/
110
111     int incoming_packet_seq;             ///< Incoming packet sequence number.
112     int incoming_flags;                  ///< Incoming packet flags.
113
114     int packet_id;                       ///< Identifier for packets in the current stream.
115     unsigned int header_packet_id;       ///< default is 2.
116
117     /** Internal handling of the ASF header */
118     /*@{*/
119     uint8_t *asf_header;                 ///< Stored ASF header.
120     int asf_header_size;                 ///< Size of stored ASF header.
121     int header_parsed;                   ///< The header has been received and parsed.
122     int asf_packet_len;
123     int asf_header_read_size;
124     /*@}*/
125
126     int stream_num;                      ///< stream numbers.
127     int is_playing;
128 } MMSContext;
129
130 /** Create MMST command packet header */
131 static void start_command_packet(MMSContext *mms, MMSCSPacketType packet_type)
132 {
133     mms->write_out_ptr = mms->out_buffer;
134
135     bytestream_put_le32(&mms->write_out_ptr, 1); // start sequence
136     bytestream_put_le32(&mms->write_out_ptr, 0xb00bface);
137     bytestream_put_le32(&mms->write_out_ptr, 0); // Length starts from after the protocol type bytes
138     bytestream_put_le32(&mms->write_out_ptr, MKTAG('M','M','S',' '));
139     bytestream_put_le32(&mms->write_out_ptr, 0);
140     bytestream_put_le32(&mms->write_out_ptr, mms->outgoing_packet_seq++);
141     bytestream_put_le64(&mms->write_out_ptr, 0); // timestamp
142     bytestream_put_le32(&mms->write_out_ptr, 0);
143     bytestream_put_le16(&mms->write_out_ptr, packet_type);
144     bytestream_put_le16(&mms->write_out_ptr, 3); // direction to server
145 }
146
147 /** Add prefixes to MMST command packet. */
148 static void insert_command_prefixes(MMSContext *mms,
149         uint32_t prefix1, uint32_t prefix2)
150 {
151     bytestream_put_le32(&mms->write_out_ptr, prefix1); // first prefix
152     bytestream_put_le32(&mms->write_out_ptr, prefix2); // second prefix
153 }
154
155 /** Send a prepared MMST command packet. */
156 static int send_command_packet(MMSContext *mms)
157 {
158     int len= mms->write_out_ptr - mms->out_buffer;
159     int exact_length = (len + 7) & ~7;
160     int first_length= exact_length - 16;
161     int len8= first_length/8;
162     int write_result;
163
164     // update packet length fields.
165     AV_WL32(mms->out_buffer + 8, first_length);
166     AV_WL32(mms->out_buffer + 16, len8);
167     AV_WL32(mms->out_buffer + 32, len8-2);
168     memset(mms->write_out_ptr, 0, exact_length - len);
169
170     // write it out.
171     write_result= url_write(mms->mms_hd, mms->out_buffer, exact_length);
172     if(write_result != exact_length) {
173         av_log(NULL, AV_LOG_ERROR,
174                "Failed to write data of length %d: %d (%s)\n",
175                exact_length, write_result,
176                write_result < 0 ? strerror(write_result) :
177                    "The server closed the connection");
178         return AVERROR_IO;
179     }
180
181     return 0;
182 }
183
184 static void mms_put_utf16(MMSContext *mms, uint8_t *src)
185 {
186     ByteIOContext bic;
187     int size = mms->write_out_ptr - mms->out_buffer;
188     int len;
189     init_put_byte(&bic, mms->write_out_ptr,
190             sizeof(mms->out_buffer) - size, 1, NULL, NULL, NULL, NULL);
191
192     len = ff_put_str16_nolen(&bic, src);
193     mms->write_out_ptr += len;
194 }
195
196 static int send_time_test_data(MMSContext *mms)
197 {
198     start_command_packet(mms, CS_PKT_TIMING_DATA_REQUEST);
199     insert_command_prefixes(mms, 0xf0f0f0f1, 0x0004000b);
200     return send_command_packet(mms);
201 }
202
203 static int send_protocol_select(MMSContext *mms)
204 {
205     char data_string[256];
206
207     start_command_packet(mms, CS_PKT_PROTOCOL_SELECT);
208     insert_command_prefixes(mms, 0, 0xffffffff);
209     bytestream_put_le32(&mms->write_out_ptr, 0);          // maxFunnelBytes
210     bytestream_put_le32(&mms->write_out_ptr, 0x00989680); // maxbitRate
211     bytestream_put_le32(&mms->write_out_ptr, 2);          // funnelMode
212     snprintf(data_string, sizeof(data_string), "\\\\%d.%d.%d.%d\\%s\\%d",
213             (LOCAL_ADDRESS>>24)&0xff,
214             (LOCAL_ADDRESS>>16)&0xff,
215             (LOCAL_ADDRESS>>8)&0xff,
216             LOCAL_ADDRESS&0xff,
217             "TCP",                                        // or UDP
218             LOCAL_PORT);
219
220     mms_put_utf16(mms, data_string);
221     return send_command_packet(mms);
222 }
223
224 static int send_media_file_request(MMSContext *mms)
225 {
226     start_command_packet(mms, CS_PKT_MEDIA_FILE_REQUEST);
227     insert_command_prefixes(mms, 1, 0xffffffff);
228     bytestream_put_le32(&mms->write_out_ptr, 0);
229     bytestream_put_le32(&mms->write_out_ptr, 0);
230     mms_put_utf16(mms, mms->path + 1); // +1 for skip "/"
231
232     return send_command_packet(mms);
233 }
234
235 static void handle_packet_stream_changing_type(MMSContext *mms)
236 {
237     dprintf(NULL, "Stream changing!\n");
238
239     // 40 is the packet header size, 7 is the prefix size.
240     mms->header_packet_id= AV_RL32(mms->in_buffer + 40 + 7);
241     dprintf(NULL, "Changed header prefix to 0x%x", mms->header_packet_id);
242 }
243
244 static int send_keepalive_packet(MMSContext *mms)
245 {
246     // respond to a keepalive with a keepalive...
247     start_command_packet(mms, CS_PKT_KEEPALIVE);
248     insert_command_prefixes(mms, 1, 0x100FFFF);
249     return send_command_packet(mms);
250 }
251
252 /** Pad media packets smaller than max_packet_size and/or adjust read position
253   * after a seek. */
254 static void pad_media_packet(MMSContext *mms)
255 {
256     if(mms->remaining_in_len<mms->asf_packet_len) {
257         int padding_size = mms->asf_packet_len - mms->remaining_in_len;
258         memset(mms->in_buffer + mms->remaining_in_len, 0, padding_size);
259         mms->remaining_in_len += padding_size;
260     }
261 }
262
263 /** Read incoming MMST media, header or command packet. */
264 static MMSSCPacketType get_tcp_server_response(MMSContext *mms)
265 {
266     int read_result;
267     MMSSCPacketType packet_type= -1;
268
269     for(;;) {
270         if((read_result= url_read_complete(mms->mms_hd, mms->in_buffer, 8))==8) {
271             // handle command packet.
272             if(AV_RL32(mms->in_buffer + 4)==0xb00bface) {
273                 mms->incoming_flags= mms->in_buffer[3];
274                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer+8, 4);
275                 if(read_result == 4) {
276                     int length_remaining= AV_RL32(mms->in_buffer+8) + 4;
277                     int hr;
278
279                     dprintf(NULL, "Length remaining is %d\n", length_remaining);
280                     // read the rest of the packet.
281                     if (length_remaining < 0
282                         || length_remaining > sizeof(mms->in_buffer) - 12) {
283                         av_log(NULL, AV_LOG_ERROR,
284                                "Incoming packet length %d exceeds bufsize %zu\n",
285                                length_remaining, sizeof(mms->in_buffer) - 12);
286                         return AVERROR_INVALIDDATA;
287                     }
288                     read_result = url_read_complete(mms->mms_hd, mms->in_buffer + 12,
289                                                   length_remaining) ;
290                     if (read_result == length_remaining) {
291                         packet_type= AV_RL16(mms->in_buffer+36);
292                     } else {
293                         av_log(NULL, AV_LOG_ERROR,
294                                "Reading pkt data (length=%d) failed: %d (%s)\n",
295                                length_remaining, read_result,
296                                read_result < 0 ? strerror(read_result) :
297                                    "The server closed the connection");
298                         return read_result < 0 ? read_result : AVERROR_IO;
299                     }
300                     hr = AV_RL32(mms->in_buffer + 40);
301                     if (hr) {
302                         av_log(NULL, AV_LOG_ERROR,
303                                "Server sent an error status code: 0x%08x\n",
304                                hr);
305                         return AVERROR_UNKNOWN;
306                     }
307                 } else {
308                     av_log(NULL, AV_LOG_ERROR,
309                            "Reading command packet length failed: %d (%s)\n",
310                            read_result,
311                            read_result < 0 ? strerror(read_result) :
312                                "The server closed the connection");
313                     return read_result < 0 ? read_result : AVERROR_IO;
314                 }
315             } else {
316                 int length_remaining;
317                 int packet_id_type;
318                 int tmp;
319
320                 // note we cache the first 8 bytes,
321                 // then fill up the buffer with the others
322                 tmp                       = AV_RL16(mms->in_buffer + 6);
323                 length_remaining          = (tmp - 8) & 0xffff;
324                 mms->incoming_packet_seq  = AV_RL32(mms->in_buffer);
325                 packet_id_type            = mms->in_buffer[4];
326                 mms->incoming_flags       = mms->in_buffer[5];
327
328                 if (length_remaining < 0
329                         || length_remaining > sizeof(mms->in_buffer) - 8) {
330                     av_log(NULL, AV_LOG_ERROR,
331                            "Data length %d is invalid or too large (max=%zu)\n",
332                            length_remaining, sizeof(mms->in_buffer));
333                     return AVERROR_INVALIDDATA;
334                 }
335                 mms->remaining_in_len    = length_remaining;
336                 mms->read_in_ptr         = mms->in_buffer;
337                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer, length_remaining);
338                 if(read_result != length_remaining) {
339                     av_log(NULL, AV_LOG_ERROR,
340                            "Failed to read packet data of size %d: %d (%s)\n",
341                            length_remaining, read_result,
342                            read_result < 0 ? strerror(read_result) :
343                                "The server closed the connection");
344                     return read_result < 0 ? read_result : AVERROR_IO;
345                 } else {
346                     // if we successfully read everything.
347                     if(packet_id_type == mms->header_packet_id) {
348                         packet_type = SC_PKT_ASF_HEADER;
349                         // Store the asf header
350                         if(!mms->header_parsed) {
351                             void *p = av_realloc(mms->asf_header,
352                                               mms->asf_header_size
353                                               + mms->remaining_in_len);
354                             if (!p) {
355                                 av_freep(&mms->asf_header);
356                                 return AVERROR(ENOMEM);
357                             }
358                             mms->asf_header = p;
359                             memcpy(mms->asf_header + mms->asf_header_size,
360                                                  mms->read_in_ptr,
361                                                  mms->remaining_in_len);
362                             mms->asf_header_size += mms->remaining_in_len;
363                         }
364                         // 0x04 means asf header is sent in multiple packets.
365                         if (mms->incoming_flags == 0x04)
366                             continue;
367                     } else if(packet_id_type == mms->packet_id) {
368                         packet_type = SC_PKT_ASF_MEDIA;
369                     } else {
370                         dprintf(NULL, "packet id type %d is old.", packet_id_type);
371                         continue;
372                     }
373                 }
374             }
375
376             // preprocess some packet type
377             if(packet_type == SC_PKT_KEEPALIVE) {
378                 send_keepalive_packet(mms);
379                 continue;
380             } else if(packet_type == SC_PKT_STREAM_CHANGING) {
381                 handle_packet_stream_changing_type(mms);
382             } else if(packet_type == SC_PKT_ASF_MEDIA) {
383                 pad_media_packet(mms);
384             }
385             return packet_type;
386         } else {
387             if(read_result<0) {
388                 av_log(NULL, AV_LOG_ERROR,
389                        "Error reading packet header: %d (%s)\n",
390                        read_result, strerror(read_result));
391                 packet_type = SC_PKT_CANCEL;
392             } else {
393                 av_log(NULL, AV_LOG_ERROR,
394                        "The server closed the connection\n");
395                 packet_type = SC_PKT_NO_DATA;
396             }
397             return packet_type;
398         }
399     }
400 }
401
402 static int mms_safe_send_recv(MMSContext *mms,
403                               int (*send_fun)(MMSContext *mms),
404                               const MMSSCPacketType expect_type)
405 {
406     MMSSCPacketType type;
407     if(send_fun) {
408         int ret = send_fun(mms);
409         if (ret < 0) {
410             dprintf(NULL, "Send Packet error before expecting recv packet %d\n", expect_type);
411             return ret;
412         }
413     }
414
415     if ((type = get_tcp_server_response(mms)) != expect_type) {
416         av_log(NULL, AV_LOG_ERROR,
417                "Corrupt stream (unexpected packet type 0x%x, expected 0x%x)\n",
418                type, expect_type);
419         return AVERROR_INVALIDDATA;
420     } else {
421         return 0;
422     }
423 }
424
425 static int send_media_header_request(MMSContext *mms)
426 {
427     start_command_packet(mms, CS_PKT_MEDIA_HEADER_REQUEST);
428     insert_command_prefixes(mms, 1, 0);
429     bytestream_put_le32(&mms->write_out_ptr, 0);
430     bytestream_put_le32(&mms->write_out_ptr, 0x00800000);
431     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff);
432     bytestream_put_le32(&mms->write_out_ptr, 0);
433     bytestream_put_le32(&mms->write_out_ptr, 0);
434     bytestream_put_le32(&mms->write_out_ptr, 0);
435
436     // the media preroll value in milliseconds?
437     bytestream_put_le32(&mms->write_out_ptr, 0);
438     bytestream_put_le32(&mms->write_out_ptr, 0x40AC2000);
439     bytestream_put_le32(&mms->write_out_ptr, 2);
440     bytestream_put_le32(&mms->write_out_ptr, 0);
441
442     return send_command_packet(mms);
443 }
444
445 /** Send the initial handshake. */
446 static int send_startup_packet(MMSContext *mms)
447 {
448     char data_string[256];
449     // SubscriberName is defined in MS specification linked below.
450     // The guid value can be any valid value.
451     // http://download.microsoft.com/
452     // download/9/5/E/95EF66AF-9026-4BB0-A41D-A4F81802D92C/%5BMS-WMSP%5D.pdf
453     snprintf(data_string, sizeof(data_string),
454             "NSPlayer/7.0.0.1956; {%s}; Host: %s",
455             "7E667F5D-A661-495E-A512-F55686DDA178", mms->host);
456
457     start_command_packet(mms, CS_PKT_INITIAL);
458     insert_command_prefixes(mms, 0, 0x0004000b);
459     bytestream_put_le32(&mms->write_out_ptr, 0x0003001c);
460     mms_put_utf16(mms, data_string);
461     return send_command_packet(mms);
462 }
463
464 static int asf_header_parser(MMSContext *mms)
465 {
466     uint8_t *p = mms->asf_header;
467     uint8_t *end;
468     int flags, stream_id;
469     mms->stream_num = 0;
470
471     if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 ||
472         memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
473         av_log(NULL, AV_LOG_ERROR,
474                "Corrupt stream (invalid ASF header, size=%d)\n",
475                mms->asf_header_size);
476         return AVERROR_INVALIDDATA;
477     }
478
479     end = mms->asf_header + mms->asf_header_size;
480
481     p += sizeof(ff_asf_guid) + 14;
482     while(end - p >= sizeof(ff_asf_guid) + 8) {
483         uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
484         if (!chunksize || chunksize > end - p) {
485             av_log(NULL, AV_LOG_ERROR,
486                    "Corrupt stream (header chunksize %"PRId64" is invalid)\n",
487                    chunksize);
488             return AVERROR_INVALIDDATA;
489         }
490         if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
491             /* read packet size */
492             if (end - p > sizeof(ff_asf_guid) * 2 + 68) {
493                 mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64);
494                 if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) {
495                     av_log(NULL, AV_LOG_ERROR,
496                            "Corrupt stream (too large pkt_len %d)\n",
497                            mms->asf_packet_len);
498                     return AVERROR_INVALIDDATA;
499                 }
500             }
501         } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) {
502             flags     = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
503             stream_id = flags & 0x7F;
504             //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
505             //we can calcuate the packet size by stream_num.
506             //Please see function send_stream_selection_request().
507             if (mms->stream_num < MAX_STREAMS &&
508                     46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
509                 mms->streams[mms->stream_num].id = stream_id;
510                 mms->stream_num++;
511             } else {
512                 av_log(NULL, AV_LOG_ERROR,
513                        "Corrupt stream (too many A/V streams)\n");
514                 return AVERROR_INVALIDDATA;
515             }
516         } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
517             chunksize = 46; // see references [2] section 3.4. This should be set 46.
518         }
519         p += chunksize;
520     }
521
522     return 0;
523 }
524
525 /** Send MMST stream selection command based on the AVStream->discard values. */
526 static int send_stream_selection_request(MMSContext *mms)
527 {
528     int i;
529
530     //  send the streams we want back...
531     start_command_packet(mms, CS_PKT_STREAM_ID_REQUEST);
532     bytestream_put_le32(&mms->write_out_ptr, mms->stream_num);         // stream nums
533     for(i= 0; i<mms->stream_num; i++) {
534         bytestream_put_le16(&mms->write_out_ptr, 0xffff);              // flags
535         bytestream_put_le16(&mms->write_out_ptr, mms->streams[i].id);  // stream id
536         bytestream_put_le16(&mms->write_out_ptr, 0);                   // selection
537     }
538     return send_command_packet(mms);
539 }
540
541 static int read_data(MMSContext *mms, uint8_t *buf, const int buf_size)
542 {
543     int read_size;
544     read_size = FFMIN(buf_size, mms->remaining_in_len);
545     memcpy(buf, mms->read_in_ptr, read_size);
546     mms->remaining_in_len -= read_size;
547     mms->read_in_ptr      += read_size;
548     return read_size;
549 }
550
551 /** Read at most one media packet (or a whole header). */
552 static int read_mms_packet(MMSContext *mms, uint8_t *buf, int buf_size)
553 {
554     int result = 0;
555     int size_to_copy;
556
557     do {
558         if(mms->asf_header_read_size < mms->asf_header_size && !mms->is_playing) {
559             /* Read from ASF header buffer */
560             size_to_copy= FFMIN(buf_size,
561                                 mms->asf_header_size - mms->asf_header_read_size);
562             memcpy(buf, mms->asf_header + mms->asf_header_read_size, size_to_copy);
563             mms->asf_header_read_size += size_to_copy;
564             result += size_to_copy;
565             dprintf(NULL, "Copied %d bytes from stored header. left: %d\n",
566                    size_to_copy, mms->asf_header_size - mms->asf_header_read_size);
567             if (mms->asf_header_size == mms->asf_header_read_size) {
568                 av_freep(&mms->asf_header);
569                 mms->is_playing = 1;
570             }
571         } else if(mms->remaining_in_len) {
572             /* Read remaining packet data to buffer.
573              * the result can not be zero because remaining_in_len is positive.*/
574             result = read_data(mms, buf, buf_size);
575         } else {
576             /* Read from network */
577             int err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_MEDIA);
578             if (err == 0) {
579                 if(mms->remaining_in_len>mms->asf_packet_len) {
580                     av_log(NULL, AV_LOG_ERROR,
581                            "Incoming pktlen %d is larger than ASF pktsize %d\n",
582                            mms->remaining_in_len, mms->asf_packet_len);
583                     result= AVERROR_IO;
584                 } else {
585                     // copy the data to the packet buffer.
586                     result = read_data(mms, buf, buf_size);
587                     if (result == 0) {
588                         dprintf(NULL, "read asf media paket size is zero!\n");
589                         break;
590                     }
591                 }
592             } else {
593                 dprintf(NULL, "read packet error!\n");
594                 break;
595             }
596         }
597     } while(!result); // only return one packet.
598     return result;
599 }
600
601 static int send_close_packet(MMSContext *mms)
602 {
603     start_command_packet(mms, CS_PKT_STREAM_CLOSE);
604     insert_command_prefixes(mms, 1, 1);
605
606     return send_command_packet(mms);
607 }
608
609 /** Close the MMSH/MMST connection */
610 static int mms_close(URLContext *h)
611 {
612     MMSContext *mms = (MMSContext *)h->priv_data;
613
614     if(mms->mms_hd) {
615         send_close_packet(mms);
616         url_close(mms->mms_hd);
617     }
618
619     /* free all separately allocated pointers in mms */
620     av_free(mms->asf_header);
621     av_freep(&h->priv_data);
622
623     return 0;
624 }
625
626 static int mms_open(URLContext *h, const char *uri, int flags)
627 {
628     MMSContext *mms;
629     int port, err;
630     char tcpname[256];
631
632     h->is_streamed = 1;
633     mms = h->priv_data = av_mallocz(sizeof(MMSContext));
634     if (!h->priv_data)
635         return AVERROR(ENOMEM);
636
637     // only for MMS over TCP, so set proto = NULL
638     av_url_split(NULL, 0, NULL, 0,
639             mms->host, sizeof(mms->host), &port, mms->path,
640             sizeof(mms->path), uri);
641
642     if(port<0)
643         port = 1755; // defaut mms protocol port
644
645     // establish tcp connection.
646     ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, mms->host, port, NULL);
647     err = url_open(&mms->mms_hd, tcpname, URL_RDWR);
648     if (err)
649         goto fail;
650
651     mms->packet_id        = 3;          // default, initial value.
652     mms->header_packet_id = 2;          // default, initial value.
653     err = mms_safe_send_recv(mms, send_startup_packet, SC_PKT_CLIENT_ACCEPTED);
654     if (err)
655         goto fail;
656     err = mms_safe_send_recv(mms, send_time_test_data, SC_PKT_TIMING_TEST_REPLY);
657     if (err)
658         goto fail;
659     err = mms_safe_send_recv(mms, send_protocol_select, SC_PKT_PROTOCOL_ACCEPTED);
660     if (err)
661         goto fail;
662     err = mms_safe_send_recv(mms, send_media_file_request, SC_PKT_MEDIA_FILE_DETAILS);
663     if (err)
664         goto fail;
665     err = mms_safe_send_recv(mms, send_media_header_request, SC_PKT_HEADER_REQUEST_ACCEPTED);
666     if (err)
667         goto fail;
668     err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_HEADER);
669     if (err)
670         goto fail;
671     if((mms->incoming_flags != 0X08) && (mms->incoming_flags != 0X0C))
672         goto fail;
673     err = asf_header_parser(mms);
674     if (err) {
675         dprintf(NULL, "asf header parsed failed!\n");
676         goto fail;
677     }
678     mms->header_parsed = 1;
679
680     if (!mms->asf_packet_len || !mms->stream_num)
681         goto fail;
682
683     dprintf(NULL, "Leaving open (success)\n");
684     return 0;
685 fail:
686     mms_close(h);
687     dprintf(NULL, "Leaving open (failure: %d)\n", err);
688     return err;
689 }
690
691 static int send_media_packet_request(MMSContext *mms)
692 {
693     start_command_packet(mms, CS_PKT_START_FROM_PKT_ID);
694     insert_command_prefixes(mms, 1, 0x0001FFFF);
695     bytestream_put_le64(&mms->write_out_ptr, 0);          // seek timestamp
696     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // unknown
697     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // packet offset
698     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
699     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
700     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
701     bytestream_put_byte(&mms->write_out_ptr, 0x00);       // stream time limit flag
702
703     mms->packet_id++;                                     // new packet_id
704     bytestream_put_le32(&mms->write_out_ptr, mms->packet_id);
705     return send_command_packet(mms);
706 }
707
708
709 static void clear_stream_buffers(MMSContext *mms)
710 {
711     mms->remaining_in_len = 0;
712     mms->read_in_ptr      = mms->in_buffer;
713 }
714
715 /** Read ASF data through the protocol. */
716 static int mms_read(URLContext *h, uint8_t *buf, int size)
717 {
718     /* TODO: see tcp.c:tcp_read() about a possible timeout scheme */
719     MMSContext *mms = h->priv_data;
720     int result = 0;
721
722     /* Since we read the header at open(), this shouldn't be possible */
723     assert(mms->header_parsed);
724
725     if (!mms->is_playing) {
726         dprintf(NULL, "mms_read() before play().\n");
727         clear_stream_buffers(mms);
728         result = mms_safe_send_recv(mms, send_stream_selection_request, SC_PKT_STREAM_ID_ACCEPTED);
729         if (result)
730             return result;
731         // send media packet request
732         result = mms_safe_send_recv(mms, send_media_packet_request, SC_PKT_MEDIA_PKT_FOLLOWS);
733         if (result) {
734             return result;
735         }
736     }
737     return read_mms_packet(mms, buf, size);
738 }
739
740 URLProtocol mmst_protocol = {
741     "mmst",
742     mms_open,
743     mms_read,
744     NULL, // write
745     NULL, // seek
746     mms_close,
747 };