rtpsend.c

RTP 实现的工具

/*
* Send RTP packet stream with configurable parameters.
* Intended to test RTP features.
* Reads RTP/RTCP headers from ASCII file, possibly generated by rtpdump.
* Format (in any order, without white space around =, lines continued
*    with initial white space, comment lines start with #, strings
*    enclosed in quotation marks):
* <time> RTP v=<version> m=<marker> pt=<payload type> ts=<time stamp>
*    seq=<sequence number> cc=<CSRC count> data=<hex payload>
* <time> RTCP (SDES v=<version> 
*               (src=<source> cname="..." name="...")
*               (src=<source> ...)
*             )
*             (RR v=<version>
*             )
*
*
* (c) 1995 Henning Schulzrinne, GMD Fokus
*/

#include <stdio.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/time.h>    /* gettimeofday() */
#include <sys/socket.h>  /* struct sockaddr */
#include <netinet/in.h>
#include <arpa/inet.h>   /* inet_ntoa() */
#include <time.h>
#include <stdio.h>       /* stderr, printf() */
#include <string.h>
#include <stdlib.h>      /* perror(), calloc() */
#include <unistd.h>      /* write() */
#include "notify.h"      /* notify_start(), ... */
#include "rtp.h"         /* RTP headers */
#include "multimer.h"    /* timer_set() */
#include "ansi.h"

static char rcsid[] = "$Id$";
static int verbose = 0;
static FILE *in = stdin;
static int sock[2];  /* output sockets */


/*
* Node either has a parameter or a non-zero pointer to list.
*/
typedef struct node {
  struct node *next, *list;  /* parameter in list, level down */ 
  char *type;    /* parameter type */
  int num;       /* numeric value */
  char *string;  /* string value */
} node_t;


static void usage(char *argv0)
{
  fprintf(stderr, "Usage: %s [-l] [-f file] destination/port/ttl\n",
    argv0);
  exit(1);
} /* usage */


/*
* Convert hexadecimal numbers in 'text' to binary in 'buffer'.
* Ignore embedded whitespace.
* Return length in bytes.
*/
static int hex(char *text, char *buffer)
{
  char *s;
  char byte[3];
  int nibble = 0;
  int len = 0;

  byte[2] = '\0';
  for (s = text; *s; s++) {
    if (isspace(*s)) continue;
    else {
      byte[nibble++] = *s;
      if (nibble == 2) {
        nibble = 0;
        buffer[len++] = strtol(byte, (char **)NULL, 16);
      }
    }
  }
  return len;
} /* hex */


/*
* Convert textual description into parse tree.
* (SDES (ssrc=<ssrc> cname=<cname> ...) (ssrc=<ssrc> ...))
* Return pointer to first node.
*/
static node_t *parse(char *text)
{
  int string = 0;
  int level = 0;
  char tmp[1024];
  int c = 0;
  node_t *n;
  node_t *first = (node_t *)NULL, *last = (node_t *)NULL;
  char *s;

  /* convert to tree */
  for (s = text; *s; s++) {
    if (string) {
      tmp[c++] = *s;
      if (*s == '"') string = 0;
    }
    else if (*s == '(') {
      if (level > 0) tmp[c++] = *s;
      else c = 0;
      level++;
    }
    else if (*s == ')') {
      level--;
      if (level == 0) {
        n = calloc(1, sizeof(node_t));
        /* append node to list */
        if (!first) first = n;
        if (last) last->next = n;
        last = n;
        tmp[c] = 0;
        c = 0;
        /* attach list */
        n->list = parse(tmp);
      }
      else {
        tmp[c++] = *s;
      }
    }
    else if (*s == '"') {
      tmp[c++] = *s;
      string = 1;
    }
    else if (level >= 1) {
      tmp[c++] = *s;
    }
    /* end of parameter/value pair */
    else if (isspace(*s)) {
      char *e;

      tmp[c] = '\0';
      if (c > 0) {
        c = 0;
        n = calloc(1, sizeof(node_t));
        if (!first) first = n;
        if (last) last->next = n;
        last = n;
        e = strchr(tmp, '=');
        if (e) {
          char *v = e+1;

          *e = '\0';
          if (isdigit(*v)) n->num = strtol(v, (char **)NULL, 0);
          else {
            n->string = malloc(strlen(v+1) + 1);
            /* strip quotation marks */
            v[strlen(v)-1] = '\0';
            strcpy(n->string, v+1);
          }
        }
        n->type = malloc(strlen(tmp) + 1);
        strcpy(n->type, tmp);      
      }
    }
    /* parameters, separated by white space */
    else {
      tmp[c++] = *s;
    }
  } 

  return first;
} /* parse */


/*
* Parse parameter=value. Return value, word becomes parameter.
* Value must be integer.
*/
static u_int32 parse_int(char *word)
{
  char *s;
  u_int32 value;

  if ((s = strchr(word, '='))) {
    value = strtol(s+1, (char **)NULL, 0);    
    *s = '\0';
  }
  else {
    *word = '\0';
  }
  return value;
} /* parse_int */


/*
* Free nodes recursively.
*/
static void node_free(node_t *list)
{
  node_t *n, *n_next;

  for (n = list; n; n = n_next) {
    if (n->type) {
      free(n->type);
      n->type = 0;
    }
    if (n->string) {
      free(n->string);
      n->string = 0;
    }
    n->num = 0;
    if (n->list) node_free(n->list);
    n_next = n->next;
    free(n);
  }
} /* node_free */


static int rtcp_sdes_item(char *type, char *string, char *packet)
{
  struct {
    char *name;
    rtcp_sdes_type_t type; 
  } map[] = {
    {"end",   RTCP_SDES_END},
    {"cname", RTCP_SDES_CNAME},
    {"name",  RTCP_SDES_NAME},
    {"email", RTCP_SDES_EMAIL},
    {"phone", RTCP_SDES_PHONE},
    {"loc",   RTCP_SDES_LOC},
    {"tool",  RTCP_SDES_TOOL},
    {"note",  RTCP_SDES_NOTE}, 
    {"priv",  RTCP_SDES_PRIV}, 
    {0,0}
  };
  int i;
  rtcp_sdes_item_t *item = (rtcp_sdes_item_t *)packet;

  for (i = 0; map[i].name; i++) {
    if (strcasecmp(type, map[i].name) == 0) break;
  }

  item->type = map[i].type;
  item->length = strlen(string);
  strcpy(item->data, string);

  return item->length + 2;
} /* rtcp_sdes_item */


/*
* Create SDES entries for single source.
* Return length.
*/
static int rtcp_sdes(node_t *list, char *packet)
{
  node_t *n;
  int len = 0, total = 4;
  struct rtcp_sdes *sdes = (struct rtcp_sdes *)packet;

  packet += 4; /* skip SRC */
  for (n = list; n; n = n->next) {
    if (n->type) {
      if (strcmp(n->type, "src") == 0) {
        sdes->src = n->num;
      }
      else {
        len = rtcp_sdes_item(n->type, n->string, packet);
        packet += len;
        total += len;
      }
    }
  }
  /* end marker */
  *packet = RTCP_SDES_END;
  total++;

  /* pad length to next multiple of 32 bits */
  len = (total + 3) & 0xfffc;
  memset(packet, 0, len - total);

  return len;
} /* rtcp_sdes */


static int rtcp_sr(node_t *n, char *packet)
{
  int length = 0;

  return length;
} /* rtcp_sr */


static int rtcp_rr(node_t *n, char *packet)
{
  int length = 0;

  return length;
} /* rtcp_rr */


static int rtcp_bye(node_t *n, char *packet)
{
  int length = 0;

  return length;
} /* rtcp_bye */


/*
* Based on list of parameters in 'n', assemble RTCP packet.
*/
static int rtcp_packet(node_t *list, char *packet)
{
  node_t *n;
  int len = 0, total = 4, count = 0;
  rtcp_t *r = (rtcp_t *)packet;
  int (*f)(node_t *list, char *packet);
  
  r->common.length  = 0;
  r->common.count   = 0;
  r->common.version = RTP_VERSION;
  r->common.p       = 0;
  packet += 4; /* skip common header */
  for (n = list; n; n = n->next) {
    if (n->type) {
      if (strcmp(n->type, "SDES") == 0) {
        f = rtcp_sdes;
        r->common.pt = RTCP_SDES;
      }
      else if (strcmp(n->type, "RR") == 0) {
        f = rtcp_rr;
        r->common.pt = RTCP_RR;
      }
      else if (strcmp(n->type, "SR") == 0) {
        f = rtcp_sr;
        r->common.pt = RTCP_SR;
      }
      else if (strcmp(n->type, "BYE") == 0) {
        f = rtcp_bye;
        r->common.pt = RTCP_BYE;
      }
      else if (strcmp(n->type, "pt") == 0) {
        r->common.pt = n->num;
      }
      else if (strcmp(n->type, "v") == 0) {
        r->common.version = n->num;
      }
      else if (strcmp(n->type, "p") == 0) {
        r->common.p = n->num;
      }
      else if (strcmp(n->type, "count") == 0) {
        r->common.count = n->num;
      }
      else if (strcmp(n->type, "len") == 0) {
        r->common.length = n->num;
      }
    }
    /* list: type-specific parts */
    else {
      len = (*f)(n->list, packet);
      packet += len;
      total += len;
      count++;
    }
  }
  /* if no length or count given, fill in */
  if (r->common.length == 0) {
    r->common.length = (total - 4) / 4;
  }
  if (r->common.count == 0) r->common.count = count;

  return total;
} /* rtcp_packet */


/*
* Generate RTCP packet based on textual description.
*/
static int rtcp(char *text, char *packet)
{
  node_t *node_list, *n;
  int len;
  int total = 0;

  node_list = parse(text);

  for (n = node_list; n; n = n->next) {
    if (n->list) {
      len = rtcp_packet(n->list, packet);
      packet += len;
      total += len;
    }
  } 
  node_free(node_list);

  return total;
} /* rtcp */


/*
* Generate RTP data packet.
*/
static int rtp(char *text, char *packet)
{
  char *word;
  int pl = 0;  /* payload length */
  int wc = 0;
  int cc = 0;
  int pad = 0;
  rtp_hdr_t *h = (rtp_hdr_t *)packet;
  int length = 0;
  u_int32 value;

  /* defaults */
  memset(packet, 0, sizeof(rtp_hdr_t));
  h->version = RTP_VERSION;

  while ((word = strtok(wc ? 0 : text, " "))) {
    value = parse_int(word);
    if (strcmp(word, "ts") == 0) {
      h->ts = htonl(value);
    }
    else if (strcmp(word, "seq") == 0) {
      h->seq = htonl(value);
    }
    else if (strcmp(word, "pt") == 0) {
      h->pt = value;
    }
    else if (strcmp(word, "ssrc") == 0) {
      h->ssrc = htonl(value);
    }
    else if (strcmp(word, "p") == 0) {
      h->p = (value != 0);
      pad = value;
    }
    else if (strcmp(word, "m") == 0) {
      h->m = value;
    }
    else if (strcmp(word, "v") == 0) {
      h->version = value;
    }
    else if (strcmp(word, "cc") == 0) {
      h->cc = value;
    }
    else if (strncmp(word, "csrc", 4) == 0) {
      int k = atoi(&word[5]);
      h->csrc[k] = value;
      if (k > cc) cc = k;
    } 
    /* data is in hex; words may be separated by spaces */
    else if (strcmp(word, "data") == 0) {
      pl = hex(&word[5], packet + 12 + h->cc*4);
    }
    else if (strcmp(word, "len") == 0) {
      length = value;
    }
    wc++;
  }
  /* fill in default values if not set */
  if (h->cc == 0) h->cc = cc;
  if (length == 0) length = 12 + h->cc * 4 + pl;

  /* insert padding */

  return length;
} /* rtp */


/*
* Generate a packet based on description in 'text'. Return length.
* Set generation time.
*/
static int generate(char *text, char *data, double *time, int *type)
{
  int length;
  char type_name[100];

  if (verbose) printf("%s", text);
  sscanf(text, "%lf %s", time, type_name);
  if (strcmp(type_name, "RTP") == 0) {
    length = rtp(strstr(text, "RTP") + 3, data);
    *type = 0;
  }
  else if (strcmp(type_name, "RTCP") == 0) {
    length = rtcp(strstr(text, "RTCP") + 4, data);
    *type = 1;
  }
  return length;
} /* generate */


/*
* Timer handler; sends any pending packets and parses next one.
* First packet is played out immediately.
*/
static Notify_value send_handler(Notify_client client)
{
  static struct {
    int length;
    double time;
    int type;
    char data[1024]; 
  } packet = { 0, -1, 0};
  FILE *in = (FILE *)client;
  static char line[2048];       /* last line read (may be next packet) */
  char text[2048];
  double this;                  /* time this packet is being sent */
  struct timeval delta;         /* next packet generation time */
  char *s;

  /* send any pending packet */
  if (packet.length && write(sock[packet.type], packet.data, packet.length) < 0) {
    perror("write");
  } 

  /* read line; continuation lines start with white space */
  if (feof(in)) {
    notify_stop();
    exit(0);
    return NOTIFY_DONE;
  }
  s = text;
  if (line[0]) {
    strcpy(text, line);
    s += strlen(text);
  }
  while (fgets(line, sizeof(line), in)) {
    if (line[0] == '#') continue;
    else if (s != text && !isspace(line[0])) break;
    else {
      strcpy(s, line);
      s += strlen(line);
    }
  }
  this = packet.time;
  packet.length = generate(text, packet.data, &packet.time, &packet.type);
  /* very first packet: send immediately */
  if (this < 0.) this = packet.time;
  else if (this > packet.time) {
    fprintf(stderr, "Non-monotonic time %f - sent immediately.\n", packet.time);
    this = packet.time;
  }

  /* compute next playout time */
  delta.tv_sec = packet.time - this;
  delta.tv_usec = ((packet.time - this) - delta.tv_sec) * 1e6;

  timer_set(&delta, send_handler, (Notify_client)in, 1);
  return NOTIFY_DONE;
} /* send_handler */


int main(int argc, char *argv[])
{
  char ttl = 16;
  static struct sockaddr_in sin;
  int i;
  int c;
  int loop = 0;   /* play file indefinitely */
  char *filename = 0;
  extern char *optarg;
  extern int optind;
  extern int hpt(char *h, struct sockaddr *sa, unsigned char *ttl);

  /* parse command line arguments */
  while ((c = getopt(argc, argv, "f:lt:v")) != EOF) {
    switch(c) {
    case 'f':
      filename = optarg;
      break;
    case 'l':
      loop = 1;
      break;
    case 'v':
      verbose = 1;
      break;
    case '?':
    case 'h':
      usage(argv[0]);
      break;
    }
  }

  if (filename) {
    in = fopen(filename, "r");
    if (!in) {
      perror(filename);
      exit(1);
    }
  }
  else {
    in = stdin;
    loop = 0;
  }

  if (optind < argc) {
    if (hpt(argv[optind], (struct sockaddr *)&sin, &ttl) < 0) usage(argv[0]);
  }

  /* create/connect sockets */
  for (i = 0; i < 2; i++) {
    sock[i] = socket(PF_INET, SOCK_DGRAM, 0);
    if (sock[i] < 0) {
      perror("socket");
      exit(1);
    }
    sin.sin_port = htons(ntohs(sin.sin_port) + i);

    if (connect(sock[i], (struct sockaddr *)&sin, sizeof(sin)) < 0) {
      perror("connect");
      exit(1);
    }

    if (IN_CLASSD(sin.sin_addr.s_addr) && 
        (setsockopt(sock[i], IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
                   sizeof(ttl)) < 0)) {
      perror("IP_MULTICAST_TTL");
      exit(1);
    }
  }

  send_handler((Notify_client)in);
  notify_start();
  return 0;
} /* main */