synsyncrecv.c

来自「linux环境下用纯c写的RTP协议的通用开发库」· C语言 代码 · 共 49 行

/*-------------------------------------------------------------------------
 * synsyncrecv.c - synsyncrecv
 *-------------------------------------------------------------------------
 */

#include <syn.h>
#include <unistd.h>
#include <util.h>

#ifdef RTPLIB_SYNCHRONIZE
/*-----------------------------------------------------------------------
 * synsyncrecv - receive and process an incoming synch request from 
 * the synchronization layer of another session. 
 * Synchronization is experimental and not well-tested.
 *-----------------------------------------------------------------------
 */
int
synsyncrecv(struct synsession *pssn, int fd)
{

	struct synsyncargs    ssa;
	int			rv, i;
	struct cnamelist	*pcnl;

	if (read(fd, (char *) &ssa, sizeof(struct synsyncargs)) < 0)
		return ERROR;
  
	if (pthread_mutex_lock(&pssn->ssn_session->sn_cnamemutex) != 0)
		return ERROR;

	pcnl = (struct cnamelist *) htget(pssn->ssn_session->sn_cnames, (unsigned int) ssa.sa_cname);
  
	rv = synsyncto(pssn, pcnl, &ssa.sa_ntp, &ssa.sa_localtime);

	if (rv == SYN_ADJUSTED) {
		for (i = 0; i < SYN_FDCNT; i++) {
			if (fd != pssn->ssn_syncfds[i] && pssn->ssn_syncfds[i] != SYN_BADFD)
				write(pssn->ssn_syncfds[i], (char *) &ssa, sizeof(struct synsyncargs));
		}
	}
	else
		if (rv == SYN_EXTERNALAHEAD)
			write(fd, (char *) &ssa, sizeof(struct synsyncargs));
  
	pthread_mutex_unlock(&pssn->ssn_session->sn_cnamemutex);
	return OK;
}
#endif /* RTPLIB_SYNCHRONIZE */