rtsp.c

mplayer播放器的源码

/*
 * This file was ported to MPlayer from xine CVS rtsp.c,v 1.9 2003/04/10 02:30:48
 */

/*
 * Copyright (C) 2000-2002 the xine project
 *
 * This file is part of xine, a free video player.
 *
 * xine is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * xine is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
 *
 *
 * a minimalistic implementation of rtsp protocol,
 * *not* RFC 2326 compilant yet.
 *
 *    2006, Benjamin Zores and Vincent Mussard
 *      fixed a lot of RFC compliance issues.
 */

#include <unistd.h>
#include <stdio.h>
#include <assert.h>
#include "config.h"
#ifndef HAVE_WINSOCK2
#define closesocket close
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#else
#include <winsock2.h>
#endif
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdlib.h>
#include <time.h>
#include <sys/time.h>
#include <sys/types.h>
#include <inttypes.h>

#include "mp_msg.h"
#include "rtsp.h"
#include "rtsp_session.h"
#include "osdep/timer.h"

/*
#define LOG
*/

#define BUF_SIZE 4096
#define HEADER_SIZE 1024
#define MAX_FIELDS 256

struct rtsp_s {

  int           s;

  char         *host;
  int           port;
  char         *path;
  char         *param;
  char         *mrl;
  char         *user_agent;

  char         *server;
  unsigned int  server_state;
  uint32_t      server_caps;
  
  unsigned int  cseq;
  char         *session;

  char        *answers[MAX_FIELDS];   /* data of last message */
  char        *scheduled[MAX_FIELDS]; /* will be sent with next message */
};

/*
 * constants
 */

#define RTSP_PROTOCOL_VERSION "RTSP/1.0"

/* server states */
#define RTSP_CONNECTED 1
#define RTSP_INIT      2
#define RTSP_READY     4
#define RTSP_PLAYING   8
#define RTSP_RECORDING 16

/* server capabilities */
#define RTSP_OPTIONS       0x001
#define RTSP_DESCRIBE      0x002
#define RTSP_ANNOUNCE      0x004
#define RTSP_SETUP         0x008
#define RTSP_GET_PARAMETER 0x010
#define RTSP_SET_PARAMETER 0x020
#define RTSP_TEARDOWN      0x040
#define RTSP_PLAY          0x080
#define RTSP_RECORD        0x100

/*
 * network utilities
 */
 
static int write_stream(int s, const char *buf, int len) {
  int total, timeout;

  total = 0; timeout = 30;
  while (total < len){ 
    int n;

    n = send (s, &buf[total], len - total, 0);

    if (n > 0)
      total += n;
    else if (n < 0) {
#ifndef HAVE_WINSOCK2
      if ((timeout>0) && ((errno == EAGAIN) || (errno == EINPROGRESS))) {
#else
      if ((timeout>0) && ((errno == EAGAIN) || (WSAGetLastError() == WSAEINPROGRESS))) {
#endif
        usec_sleep (1000000); timeout--;
      } else
        return -1;
    }
  }

  return total;
}

static ssize_t read_stream(int fd, void *buf, size_t count) {
  
  ssize_t ret, total;

  total = 0;

  while (total < count) {
  
    ret=recv (fd, ((uint8_t*)buf)+total, count-total, 0);

    if (ret<0) {
      if(errno == EAGAIN) {
        fd_set rset;
        struct timeval timeout;
    
        FD_ZERO (&rset);
        FD_SET  (fd, &rset);
        
        timeout.tv_sec  = 30;
        timeout.tv_usec = 0;
        
        if (select (fd+1, &rset, NULL, NULL, &timeout) <= 0) {
          return -1;
        }
        continue;
      }
      
      mp_msg(MSGT_OPEN, MSGL_ERR, "rtsp: read error.\n");
      return ret;
    } else
      total += ret;
    
    /* end of stream */
    if (!ret) break;
  }

  return total;
}

/*
 * rtsp_get gets a line from stream
 * and returns a null terminated string.
 */
 
static char *rtsp_get(rtsp_t *s) {

  int n=1;
  char *buffer = malloc(BUF_SIZE);
  char *string = NULL;

  read_stream(s->s, buffer, 1);
  while (n<BUF_SIZE) {
    read_stream(s->s, &(buffer[n]), 1);
    if ((buffer[n-1]==0x0d)&&(buffer[n]==0x0a)) break;
    n++;
  }

  if (n>=BUF_SIZE) {
    mp_msg(MSGT_OPEN, MSGL_FATAL, "librtsp: buffer overflow in rtsp_get\n");
    exit(1);
  }
  string=malloc(n);
  memcpy(string,buffer,n-1);
  string[n-1]=0;

#ifdef LOG
  mp_msg(MSGT_OPEN, MSGL_INFO, "librtsp: << '%s'\n", string);
#endif
  

  free(buffer);
  return string;
}

/*
 * rtsp_put puts a line on stream
 */
 
static void rtsp_put(rtsp_t *s, const char *string) {

  int len=strlen(string);
  char *buf=malloc(len+2);

#ifdef LOG
  mp_msg(MSGT_OPEN, MSGL_INFO, "librtsp: >> '%s'", string);
#endif

  memcpy(buf,string,len);
  buf[len]=0x0d;
  buf[len+1]=0x0a;

  write_stream(s->s, buf, len+2);
  
#ifdef LOG
  mp_msg(MSGT_OPEN, MSGL_INFO, " done.\n");
#endif

  free(buf);
}

/*
 * extract server status code
 */

static int rtsp_get_code(const char *string) {

  char buf[4];
  int code=0;
 
  if (!strncmp(string, RTSP_PROTOCOL_VERSION, strlen(RTSP_PROTOCOL_VERSION)))
  {
    memcpy(buf, string+strlen(RTSP_PROTOCOL_VERSION)+1, 3);
    buf[3]=0;
    code=atoi(buf);
  } else if (!strncmp(string, RTSP_METHOD_SET_PARAMETER,8))
  {
    return RTSP_STATUS_SET_PARAMETER;
  }

  if(code != RTSP_STATUS_OK) mp_msg(MSGT_OPEN, MSGL_INFO, "librtsp: server responds: '%s'\n",string);

  return code;
}

/*
 * send a request
 */

static void rtsp_send_request(rtsp_t *s, const char *type, const char *what) {

  char **payload=s->scheduled;
  char *buf;
  
  buf = malloc(strlen(type)+strlen(what)+strlen(RTSP_PROTOCOL_VERSION)+3);
  
  sprintf(buf,"%s %s %s",type, what, RTSP_PROTOCOL_VERSION);
  rtsp_put(s,buf);
  free(buf);
  if (payload)
    while (*payload) {
      rtsp_put(s,*payload);
      payload++;
    }
  rtsp_put(s,"");
  rtsp_unschedule_all(s);
}

/*
 * schedule standard fields
 */

static void rtsp_schedule_standard(rtsp_t *s) {

  char tmp[17];
  
  snprintf(tmp, 17, "CSeq: %u", s->cseq);
  rtsp_schedule_field(s, tmp);
  
  if (s->session) {
    char *buf;
    buf = malloc(strlen(s->session)+15);
    sprintf(buf, "Session: %s", s->session);
    rtsp_schedule_field(s, buf);
    free(buf);
  }
}
/*
 * get the answers, if server responses with something != 200, return NULL
 */
 
static int rtsp_get_answers(rtsp_t *s) {

  char *answer=NULL;
  unsigned int answer_seq;
  char **answer_ptr=s->answers;
  int code;
  int ans_count = 0;
  
  answer=rtsp_get(s);
  if (!answer)
    return 0;
  code=rtsp_get_code(answer);
  free(answer);

  rtsp_free_answers(s);
  
  do { /* while we get answer lines */
  
    answer=rtsp_get(s);
    if (!answer)
      return 0;
    
    if (!strncasecmp(answer,"CSeq:",5)) {
      sscanf(answer,"%*s %u",&answer_seq);
      if (s->cseq != answer_seq) {
#ifdef LOG
        mp_msg(MSGT_OPEN, MSGL_WARN, "librtsp: warning: CSeq mismatch. got %u, assumed %u", answer_seq, s->cseq);
#endif
        s->cseq=answer_seq;
      }
    }
    if (!strncasecmp(answer,"Server:",7)) {
      char *buf = malloc(strlen(answer));
      sscanf(answer,"%*s %s",buf);
      if (s->server) free(s->server);
      s->server=strdup(buf);
      free(buf);
    }
    if (!strncasecmp(answer,"Session:",8)) {
      char *buf = calloc(1, strlen(answer));
      sscanf(answer,"%*s %s",buf);
      if (s->session) {
        if (strcmp(buf, s->session)) {
          mp_msg(MSGT_OPEN, MSGL_WARN, "rtsp: warning: setting NEW session: %s\n", buf);
          free(s->session);
          s->session=strdup(buf);
        }
      } else
      {
#ifdef LOG
        mp_msg(MSGT_OPEN, MSGL_INFO, "rtsp: setting session id to: %s\n", buf);
#endif
        s->session=strdup(buf);
      }
      free(buf);
    }
    *answer_ptr=answer;
    answer_ptr++;
  } while ((strlen(answer)!=0) && (++ans_count < MAX_FIELDS));
  
  s->cseq++;
  
  *answer_ptr=NULL;
  rtsp_schedule_standard(s);
    
  return code;
}

/*
 * send an ok message
 */

int rtsp_send_ok(rtsp_t *s) {
  char cseq[16];
  
  rtsp_put(s, "RTSP/1.0 200 OK");
  sprintf(cseq,"CSeq: %u", s->cseq);
  rtsp_put(s, cseq);
  rtsp_put(s, "");
  return 0;
}

/*
 * implementation of must-have rtsp requests; functions return
 * server status code.
 */

int rtsp_request_options(rtsp_t *s, const char *what) {

  char *buf;