diff options
Diffstat (limited to 'src/rtime.c')
-rw-r--r-- | src/rtime.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/src/rtime.c b/src/rtime.c new file mode 100644 index 0000000..29fbf0a --- /dev/null +++ b/src/rtime.c @@ -0,0 +1,157 @@ +/* + * Copyright (c) 2009, Sun Microsystems, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * - Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * - Neither the name of Sun Microsystems, Inc. nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * Copyright (c) 1988 by Sun Microsystems, Inc. + + */ + +/* + * rtime - get time from remote machine + * + * gets time, obtaining value from host + * on the udp/time socket. Since timeserver returns + * with time of day in seconds since Jan 1, 1900, must + * subtract seconds before Jan 1, 1970 to get + * what unix uses. + */ +#include <pthread.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/poll.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <netinet/in.h> +#include <stdio.h> +#include <netdb.h> +#include <sys/select.h> + +extern int _rpc_dtablesize( void ); + +#define NYEARS (unsigned long)(1970 - 1900) +#define TOFFSET (unsigned long)(60*60*24*(365*NYEARS + (NYEARS/4))) + +static void do_close( int ); + +int +rtime(addrp, timep, timeout) + struct sockaddr_in *addrp; + struct timeval *timep; + struct timeval *timeout; +{ + int s; + struct pollfd fd; + int milliseconds; + int res; + unsigned long thetime; + struct sockaddr_in from; + socklen_t fromlen; + int type; + struct servent *serv; + + if (timeout == NULL) { + type = SOCK_STREAM; + } else { + type = SOCK_DGRAM; + } + s = socket(AF_INET, type, 0); + if (s < 0) { + return(-1); + } + addrp->sin_family = AF_INET; + + /* TCP and UDP port are the same in this case */ + if ((serv = getservbyname("time", "tcp")) == NULL) { + do_close(s); + return(-1); + } + + addrp->sin_port = serv->s_port; + + if (type == SOCK_DGRAM) { + res = sendto(s, (char *)&thetime, sizeof(thetime), 0, + (struct sockaddr *)addrp, sizeof(*addrp)); + if (res < 0) { + do_close(s); + return(-1); + } + + milliseconds = (timeout->tv_sec * 1000) + (timeout->tv_usec / 1000); + fd.fd = s; + fd.events = POLLIN; + do + res = poll (&fd, 1, milliseconds); + while (res < 0 && errno == EINTR); + if (res <= 0) { + if (res == 0) { + errno = ETIMEDOUT; + } + do_close(s); + return(-1); + } + fromlen = sizeof(from); + res = recvfrom(s, (char *)&thetime, sizeof(thetime), 0, + (struct sockaddr *)&from, &fromlen); + do_close(s); + if (res < 0) { + return(-1); + } + } else { + if (connect(s, (struct sockaddr *)addrp, sizeof(*addrp)) < 0) { + do_close(s); + return(-1); + } + res = read(s, (char *)&thetime, sizeof(thetime)); + do_close(s); + if (res < 0) { + return(-1); + } + } + if (res != sizeof(thetime)) { + errno = EIO; + return(-1); + } + thetime = ntohl(thetime); + timep->tv_sec = thetime - TOFFSET; + timep->tv_usec = 0; + return(0); +} + +static void +do_close(s) + int s; +{ + int save; + + save = errno; + (void)close(s); + errno = save; +} |