Move read_mms_packet() code to be inlined in the calling function.
[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 } MMSContext;
128
129 /** Create MMST command packet header */
130 static void start_command_packet(MMSContext *mms, MMSCSPacketType packet_type)
131 {
132     mms->write_out_ptr = mms->out_buffer;
133
134     bytestream_put_le32(&mms->write_out_ptr, 1); // start sequence
135     bytestream_put_le32(&mms->write_out_ptr, 0xb00bface);
136     bytestream_put_le32(&mms->write_out_ptr, 0); // Length starts from after the protocol type bytes
137     bytestream_put_le32(&mms->write_out_ptr, MKTAG('M','M','S',' '));
138     bytestream_put_le32(&mms->write_out_ptr, 0);
139     bytestream_put_le32(&mms->write_out_ptr, mms->outgoing_packet_seq++);
140     bytestream_put_le64(&mms->write_out_ptr, 0); // timestamp
141     bytestream_put_le32(&mms->write_out_ptr, 0);
142     bytestream_put_le16(&mms->write_out_ptr, packet_type);
143     bytestream_put_le16(&mms->write_out_ptr, 3); // direction to server
144 }
145
146 /** Add prefixes to MMST command packet. */
147 static void insert_command_prefixes(MMSContext *mms,
148         uint32_t prefix1, uint32_t prefix2)
149 {
150     bytestream_put_le32(&mms->write_out_ptr, prefix1); // first prefix
151     bytestream_put_le32(&mms->write_out_ptr, prefix2); // second prefix
152 }
153
154 /** Send a prepared MMST command packet. */
155 static int send_command_packet(MMSContext *mms)
156 {
157     int len= mms->write_out_ptr - mms->out_buffer;
158     int exact_length = (len + 7) & ~7;
159     int first_length= exact_length - 16;
160     int len8= first_length/8;
161     int write_result;
162
163     // update packet length fields.
164     AV_WL32(mms->out_buffer + 8, first_length);
165     AV_WL32(mms->out_buffer + 16, len8);
166     AV_WL32(mms->out_buffer + 32, len8-2);
167     memset(mms->write_out_ptr, 0, exact_length - len);
168
169     // write it out.
170     write_result= url_write(mms->mms_hd, mms->out_buffer, exact_length);
171     if(write_result != exact_length) {
172         av_log(NULL, AV_LOG_ERROR,
173                "Failed to write data of length %d: %d (%s)\n",
174                exact_length, write_result,
175                write_result < 0 ? strerror(write_result) :
176                    "The server closed the connection");
177         return AVERROR_IO;
178     }
179
180     return 0;
181 }
182
183 static void mms_put_utf16(MMSContext *mms, uint8_t *src)
184 {
185     ByteIOContext bic;
186     int size = mms->write_out_ptr - mms->out_buffer;
187     int len;
188     init_put_byte(&bic, mms->write_out_ptr,
189             sizeof(mms->out_buffer) - size, 1, NULL, NULL, NULL, NULL);
190
191     len = ff_put_str16_nolen(&bic, src);
192     mms->write_out_ptr += len;
193 }
194
195 static int send_time_test_data(MMSContext *mms)
196 {
197     start_command_packet(mms, CS_PKT_TIMING_DATA_REQUEST);
198     insert_command_prefixes(mms, 0xf0f0f0f1, 0x0004000b);
199     return send_command_packet(mms);
200 }
201
202 static int send_protocol_select(MMSContext *mms)
203 {
204     char data_string[256];
205
206     start_command_packet(mms, CS_PKT_PROTOCOL_SELECT);
207     insert_command_prefixes(mms, 0, 0xffffffff);
208     bytestream_put_le32(&mms->write_out_ptr, 0);          // maxFunnelBytes
209     bytestream_put_le32(&mms->write_out_ptr, 0x00989680); // maxbitRate
210     bytestream_put_le32(&mms->write_out_ptr, 2);          // funnelMode
211     snprintf(data_string, sizeof(data_string), "\\\\%d.%d.%d.%d\\%s\\%d",
212             (LOCAL_ADDRESS>>24)&0xff,
213             (LOCAL_ADDRESS>>16)&0xff,
214             (LOCAL_ADDRESS>>8)&0xff,
215             LOCAL_ADDRESS&0xff,
216             "TCP",                                        // or UDP
217             LOCAL_PORT);
218
219     mms_put_utf16(mms, data_string);
220     return send_command_packet(mms);
221 }
222
223 static int send_media_file_request(MMSContext *mms)
224 {
225     start_command_packet(mms, CS_PKT_MEDIA_FILE_REQUEST);
226     insert_command_prefixes(mms, 1, 0xffffffff);
227     bytestream_put_le32(&mms->write_out_ptr, 0);
228     bytestream_put_le32(&mms->write_out_ptr, 0);
229     mms_put_utf16(mms, mms->path + 1); // +1 for skip "/"
230
231     return send_command_packet(mms);
232 }
233
234 static void handle_packet_stream_changing_type(MMSContext *mms)
235 {
236     dprintf(NULL, "Stream changing!\n");
237
238     // 40 is the packet header size, 7 is the prefix size.
239     mms->header_packet_id= AV_RL32(mms->in_buffer + 40 + 7);
240     dprintf(NULL, "Changed header prefix to 0x%x", mms->header_packet_id);
241 }
242
243 static int send_keepalive_packet(MMSContext *mms)
244 {
245     // respond to a keepalive with a keepalive...
246     start_command_packet(mms, CS_PKT_KEEPALIVE);
247     insert_command_prefixes(mms, 1, 0x100FFFF);
248     return send_command_packet(mms);
249 }
250
251 /** Pad media packets smaller than max_packet_size and/or adjust read position
252   * after a seek. */
253 static void pad_media_packet(MMSContext *mms)
254 {
255     if(mms->remaining_in_len<mms->asf_packet_len) {
256         int padding_size = mms->asf_packet_len - mms->remaining_in_len;
257         memset(mms->in_buffer + mms->remaining_in_len, 0, padding_size);
258         mms->remaining_in_len += padding_size;
259     }
260 }
261
262 /** Read incoming MMST media, header or command packet. */
263 static MMSSCPacketType get_tcp_server_response(MMSContext *mms)
264 {
265     int read_result;
266     MMSSCPacketType packet_type= -1;
267
268     for(;;) {
269         read_result = url_read_complete(mms->mms_hd, mms->in_buffer, 8);
270         if (read_result != 8) {
271             if(read_result < 0) {
272                 av_log(NULL, AV_LOG_ERROR,
273                        "Error reading packet header: %d (%s)\n",
274                        read_result, strerror(read_result));
275                 packet_type = SC_PKT_CANCEL;
276             } else {
277                 av_log(NULL, AV_LOG_ERROR,
278                        "The server closed the connection\n");
279                 packet_type = SC_PKT_NO_DATA;
280             }
281             return packet_type;
282         }
283
284         // handle command packet.
285         if(AV_RL32(mms->in_buffer + 4)==0xb00bface) {
286             int length_remaining, hr;
287
288             mms->incoming_flags= mms->in_buffer[3];
289             read_result= url_read_complete(mms->mms_hd, mms->in_buffer+8, 4);
290             if(read_result != 4) {
291                 av_log(NULL, AV_LOG_ERROR,
292                        "Reading command packet length failed: %d (%s)\n",
293                        read_result,
294                        read_result < 0 ? strerror(read_result) :
295                            "The server closed the connection");
296                 return read_result < 0 ? read_result : AVERROR_IO;
297             }
298
299             length_remaining= AV_RL32(mms->in_buffer+8) + 4;
300             dprintf(NULL, "Length remaining is %d\n", length_remaining);
301             // read the rest of the packet.
302             if (length_remaining < 0
303                 || length_remaining > sizeof(mms->in_buffer) - 12) {
304                 av_log(NULL, AV_LOG_ERROR,
305                        "Incoming packet length %d exceeds bufsize %zu\n",
306                        length_remaining, sizeof(mms->in_buffer) - 12);
307                 return AVERROR_INVALIDDATA;
308             }
309             read_result = url_read_complete(mms->mms_hd, mms->in_buffer + 12,
310                                             length_remaining) ;
311             if (read_result != length_remaining) {
312                 av_log(NULL, AV_LOG_ERROR,
313                        "Reading pkt data (length=%d) failed: %d (%s)\n",
314                        length_remaining, read_result,
315                        read_result < 0 ? strerror(read_result) :
316                            "The server closed the connection");
317                 return read_result < 0 ? read_result : AVERROR_IO;
318             }
319             packet_type= AV_RL16(mms->in_buffer+36);
320             hr = AV_RL32(mms->in_buffer + 40);
321             if (hr) {
322                 av_log(NULL, AV_LOG_ERROR,
323                        "Server sent an error status code: 0x%08x\n", hr);
324                 return AVERROR_UNKNOWN;
325             }
326         } else {
327             int length_remaining;
328             int packet_id_type;
329             int tmp;
330
331             // note we cache the first 8 bytes,
332             // then fill up the buffer with the others
333             tmp                       = AV_RL16(mms->in_buffer + 6);
334             length_remaining          = (tmp - 8) & 0xffff;
335             mms->incoming_packet_seq  = AV_RL32(mms->in_buffer);
336             packet_id_type            = mms->in_buffer[4];
337             mms->incoming_flags       = mms->in_buffer[5];
338
339             if (length_remaining < 0
340                 || length_remaining > sizeof(mms->in_buffer) - 8) {
341                 av_log(NULL, AV_LOG_ERROR,
342                        "Data length %d is invalid or too large (max=%zu)\n",
343                        length_remaining, sizeof(mms->in_buffer));
344                 return AVERROR_INVALIDDATA;
345             }
346             mms->remaining_in_len    = length_remaining;
347             mms->read_in_ptr         = mms->in_buffer;
348             read_result= url_read_complete(mms->mms_hd, mms->in_buffer, length_remaining);
349             if(read_result != length_remaining) {
350                 av_log(NULL, AV_LOG_ERROR,
351                        "Failed to read packet data of size %d: %d (%s)\n",
352                        length_remaining, read_result,
353                        read_result < 0 ? strerror(read_result) :
354                            "The server closed the connection");
355                 return read_result < 0 ? read_result : AVERROR_IO;
356             }
357
358             // if we successfully read everything.
359             if(packet_id_type == mms->header_packet_id) {
360                 packet_type = SC_PKT_ASF_HEADER;
361                 // Store the asf header
362                 if(!mms->header_parsed) {
363                     void *p = av_realloc(mms->asf_header,
364                                   mms->asf_header_size + mms->remaining_in_len);
365                     if (!p) {
366                         av_freep(&mms->asf_header);
367                         return AVERROR(ENOMEM);
368                     }
369                     mms->asf_header = p;
370                     memcpy(mms->asf_header + mms->asf_header_size,
371                            mms->read_in_ptr, mms->remaining_in_len);
372                     mms->asf_header_size += mms->remaining_in_len;
373                 }
374                 // 0x04 means asf header is sent in multiple packets.
375                 if (mms->incoming_flags == 0x04)
376                     continue;
377             } else if(packet_id_type == mms->packet_id) {
378                 packet_type = SC_PKT_ASF_MEDIA;
379             } else {
380                 dprintf(NULL, "packet id type %d is old.", packet_id_type);
381                 continue;
382             }
383         }
384
385         // preprocess some packet type
386         if(packet_type == SC_PKT_KEEPALIVE) {
387             send_keepalive_packet(mms);
388             continue;
389         } else if(packet_type == SC_PKT_STREAM_CHANGING) {
390             handle_packet_stream_changing_type(mms);
391         } else if(packet_type == SC_PKT_ASF_MEDIA) {
392             pad_media_packet(mms);
393         }
394         return packet_type;
395     }
396 }
397
398 static int mms_safe_send_recv(MMSContext *mms,
399                               int (*send_fun)(MMSContext *mms),
400                               const MMSSCPacketType expect_type)
401 {
402     MMSSCPacketType type;
403     if(send_fun) {
404         int ret = send_fun(mms);
405         if (ret < 0) {
406             dprintf(NULL, "Send Packet error before expecting recv packet %d\n", expect_type);
407             return ret;
408         }
409     }
410
411     if ((type = get_tcp_server_response(mms)) != expect_type) {
412         av_log(NULL, AV_LOG_ERROR,
413                "Corrupt stream (unexpected packet type 0x%x, expected 0x%x)\n",
414                type, expect_type);
415         return AVERROR_INVALIDDATA;
416     } else {
417         return 0;
418     }
419 }
420
421 static int send_media_header_request(MMSContext *mms)
422 {
423     start_command_packet(mms, CS_PKT_MEDIA_HEADER_REQUEST);
424     insert_command_prefixes(mms, 1, 0);
425     bytestream_put_le32(&mms->write_out_ptr, 0);
426     bytestream_put_le32(&mms->write_out_ptr, 0x00800000);
427     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff);
428     bytestream_put_le32(&mms->write_out_ptr, 0);
429     bytestream_put_le32(&mms->write_out_ptr, 0);
430     bytestream_put_le32(&mms->write_out_ptr, 0);
431
432     // the media preroll value in milliseconds?
433     bytestream_put_le32(&mms->write_out_ptr, 0);
434     bytestream_put_le32(&mms->write_out_ptr, 0x40AC2000);
435     bytestream_put_le32(&mms->write_out_ptr, 2);
436     bytestream_put_le32(&mms->write_out_ptr, 0);
437
438     return send_command_packet(mms);
439 }
440
441 /** Send the initial handshake. */
442 static int send_startup_packet(MMSContext *mms)
443 {
444     char data_string[256];
445     // SubscriberName is defined in MS specification linked below.
446     // The guid value can be any valid value.
447     // http://download.microsoft.com/
448     // download/9/5/E/95EF66AF-9026-4BB0-A41D-A4F81802D92C/%5BMS-WMSP%5D.pdf
449     snprintf(data_string, sizeof(data_string),
450             "NSPlayer/7.0.0.1956; {%s}; Host: %s",
451             "7E667F5D-A661-495E-A512-F55686DDA178", mms->host);
452
453     start_command_packet(mms, CS_PKT_INITIAL);
454     insert_command_prefixes(mms, 0, 0x0004000b);
455     bytestream_put_le32(&mms->write_out_ptr, 0x0003001c);
456     mms_put_utf16(mms, data_string);
457     return send_command_packet(mms);
458 }
459
460 static int asf_header_parser(MMSContext *mms)
461 {
462     uint8_t *p = mms->asf_header;
463     uint8_t *end;
464     int flags, stream_id;
465     mms->stream_num = 0;
466
467     if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 ||
468         memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
469         av_log(NULL, AV_LOG_ERROR,
470                "Corrupt stream (invalid ASF header, size=%d)\n",
471                mms->asf_header_size);
472         return AVERROR_INVALIDDATA;
473     }
474
475     end = mms->asf_header + mms->asf_header_size;
476
477     p += sizeof(ff_asf_guid) + 14;
478     while(end - p >= sizeof(ff_asf_guid) + 8) {
479         uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
480         if (!chunksize || chunksize > end - p) {
481             av_log(NULL, AV_LOG_ERROR,
482                    "Corrupt stream (header chunksize %"PRId64" is invalid)\n",
483                    chunksize);
484             return AVERROR_INVALIDDATA;
485         }
486         if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
487             /* read packet size */
488             if (end - p > sizeof(ff_asf_guid) * 2 + 68) {
489                 mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64);
490                 if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) {
491                     av_log(NULL, AV_LOG_ERROR,
492                            "Corrupt stream (too large pkt_len %d)\n",
493                            mms->asf_packet_len);
494                     return AVERROR_INVALIDDATA;
495                 }
496             }
497         } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) {
498             flags     = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
499             stream_id = flags & 0x7F;
500             //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
501             //we can calcuate the packet size by stream_num.
502             //Please see function send_stream_selection_request().
503             if (mms->stream_num < MAX_STREAMS &&
504                     46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
505                 mms->streams[mms->stream_num].id = stream_id;
506                 mms->stream_num++;
507             } else {
508                 av_log(NULL, AV_LOG_ERROR,
509                        "Corrupt stream (too many A/V streams)\n");
510                 return AVERROR_INVALIDDATA;
511             }
512         } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
513             chunksize = 46; // see references [2] section 3.4. This should be set 46.
514         }
515         p += chunksize;
516     }
517
518     return 0;
519 }
520
521 /** Send MMST stream selection command based on the AVStream->discard values. */
522 static int send_stream_selection_request(MMSContext *mms)
523 {
524     int i;
525
526     //  send the streams we want back...
527     start_command_packet(mms, CS_PKT_STREAM_ID_REQUEST);
528     bytestream_put_le32(&mms->write_out_ptr, mms->stream_num);         // stream nums
529     for(i= 0; i<mms->stream_num; i++) {
530         bytestream_put_le16(&mms->write_out_ptr, 0xffff);              // flags
531         bytestream_put_le16(&mms->write_out_ptr, mms->streams[i].id);  // stream id
532         bytestream_put_le16(&mms->write_out_ptr, 0);                   // selection
533     }
534     return send_command_packet(mms);
535 }
536
537 static int read_data(MMSContext *mms, uint8_t *buf, const int buf_size)
538 {
539     int read_size;
540     read_size = FFMIN(buf_size, mms->remaining_in_len);
541     memcpy(buf, mms->read_in_ptr, read_size);
542     mms->remaining_in_len -= read_size;
543     mms->read_in_ptr      += read_size;
544     return read_size;
545 }
546
547 static int send_close_packet(MMSContext *mms)
548 {
549     start_command_packet(mms, CS_PKT_STREAM_CLOSE);
550     insert_command_prefixes(mms, 1, 1);
551
552     return send_command_packet(mms);
553 }
554
555 /** Close the MMSH/MMST connection */
556 static int mms_close(URLContext *h)
557 {
558     MMSContext *mms = (MMSContext *)h->priv_data;
559
560     if(mms->mms_hd) {
561         send_close_packet(mms);
562         url_close(mms->mms_hd);
563     }
564
565     /* free all separately allocated pointers in mms */
566     av_free(mms->asf_header);
567     av_freep(&h->priv_data);
568
569     return 0;
570 }
571
572 static int send_media_packet_request(MMSContext *mms)
573 {
574     start_command_packet(mms, CS_PKT_START_FROM_PKT_ID);
575     insert_command_prefixes(mms, 1, 0x0001FFFF);
576     bytestream_put_le64(&mms->write_out_ptr, 0);          // seek timestamp
577     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // unknown
578     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // packet offset
579     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
580     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
581     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
582     bytestream_put_byte(&mms->write_out_ptr, 0x00);       // stream time limit flag
583
584     mms->packet_id++;                                     // new packet_id
585     bytestream_put_le32(&mms->write_out_ptr, mms->packet_id);
586     return send_command_packet(mms);
587 }
588
589
590 static void clear_stream_buffers(MMSContext *mms)
591 {
592     mms->remaining_in_len = 0;
593     mms->read_in_ptr      = mms->in_buffer;
594 }
595
596 static int mms_open(URLContext *h, const char *uri, int flags)
597 {
598     MMSContext *mms;
599     int port, err;
600     char tcpname[256];
601
602     h->is_streamed = 1;
603     mms = h->priv_data = av_mallocz(sizeof(MMSContext));
604     if (!h->priv_data)
605         return AVERROR(ENOMEM);
606
607     // only for MMS over TCP, so set proto = NULL
608     av_url_split(NULL, 0, NULL, 0,
609             mms->host, sizeof(mms->host), &port, mms->path,
610             sizeof(mms->path), uri);
611
612     if(port<0)
613         port = 1755; // defaut mms protocol port
614
615     // establish tcp connection.
616     ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, mms->host, port, NULL);
617     err = url_open(&mms->mms_hd, tcpname, URL_RDWR);
618     if (err)
619         goto fail;
620
621     mms->packet_id        = 3;          // default, initial value.
622     mms->header_packet_id = 2;          // default, initial value.
623     err = mms_safe_send_recv(mms, send_startup_packet, SC_PKT_CLIENT_ACCEPTED);
624     if (err)
625         goto fail;
626     err = mms_safe_send_recv(mms, send_time_test_data, SC_PKT_TIMING_TEST_REPLY);
627     if (err)
628         goto fail;
629     err = mms_safe_send_recv(mms, send_protocol_select, SC_PKT_PROTOCOL_ACCEPTED);
630     if (err)
631         goto fail;
632     err = mms_safe_send_recv(mms, send_media_file_request, SC_PKT_MEDIA_FILE_DETAILS);
633     if (err)
634         goto fail;
635     err = mms_safe_send_recv(mms, send_media_header_request, SC_PKT_HEADER_REQUEST_ACCEPTED);
636     if (err)
637         goto fail;
638     err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_HEADER);
639     if (err)
640         goto fail;
641     if((mms->incoming_flags != 0X08) && (mms->incoming_flags != 0X0C))
642         goto fail;
643     err = asf_header_parser(mms);
644     if (err) {
645         dprintf(NULL, "asf header parsed failed!\n");
646         goto fail;
647     }
648     mms->header_parsed = 1;
649
650     if (!mms->asf_packet_len || !mms->stream_num)
651         goto fail;
652
653     clear_stream_buffers(mms);
654     err = mms_safe_send_recv(mms, send_stream_selection_request, SC_PKT_STREAM_ID_ACCEPTED);
655     if (err)
656         goto fail;
657     // send media packet request
658     err = mms_safe_send_recv(mms, send_media_packet_request, SC_PKT_MEDIA_PKT_FOLLOWS);
659     if (err) {
660         goto fail;
661     }
662     dprintf(NULL, "Leaving open (success)\n");
663     return 0;
664 fail:
665     mms_close(h);
666     dprintf(NULL, "Leaving open (failure: %d)\n", err);
667     return err;
668 }
669
670 /** Read ASF data through the protocol. */
671 static int mms_read(URLContext *h, uint8_t *buf, int size)
672 {
673     /* TODO: see tcp.c:tcp_read() about a possible timeout scheme */
674     MMSContext *mms = h->priv_data;
675     int result = 0;
676     int size_to_copy;
677
678     do {
679         if(mms->asf_header_read_size < mms->asf_header_size) {
680             /* Read from ASF header buffer */
681             size_to_copy= FFMIN(size,
682                                 mms->asf_header_size - mms->asf_header_read_size);
683             memcpy(buf, mms->asf_header + mms->asf_header_read_size, size_to_copy);
684             mms->asf_header_read_size += size_to_copy;
685             result += size_to_copy;
686             dprintf(NULL, "Copied %d bytes from stored header. left: %d\n",
687                    size_to_copy, mms->asf_header_size - mms->asf_header_read_size);
688             if (mms->asf_header_size == mms->asf_header_read_size) {
689                 av_freep(&mms->asf_header);
690             }
691         } else if(mms->remaining_in_len) {
692             /* Read remaining packet data to buffer.
693              * the result can not be zero because remaining_in_len is positive.*/
694             result = read_data(mms, buf, size);
695         } else {
696             /* Read from network */
697             int err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_MEDIA);
698             if (err == 0) {
699                 if(mms->remaining_in_len>mms->asf_packet_len) {
700                     av_log(NULL, AV_LOG_ERROR,
701                            "Incoming pktlen %d is larger than ASF pktsize %d\n",
702                            mms->remaining_in_len, mms->asf_packet_len);
703                     result= AVERROR_IO;
704                 } else {
705                     // copy the data to the packet buffer.
706                     result = read_data(mms, buf, size);
707                     if (result == 0) {
708                         dprintf(NULL, "read asf media paket size is zero!\n");
709                         break;
710                     }
711                 }
712             } else {
713                 dprintf(NULL, "read packet error!\n");
714                 break;
715             }
716         }
717     } while(!result); // only return one packet.
718     return result;
719 }
720
721 URLProtocol mmst_protocol = {
722     "mmst",
723     mms_open,
724     mms_read,
725     NULL, // write
726     NULL, // seek
727     mms_close,
728 };