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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <syslog.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "btime_int.h"
static unsigned int get_btime(void);
int
main(int argc, char **argv)
{
int sd;
char inmsg[BTIME_MSGLEN];
char outmsg[BTIME_MSGLEN];
struct sockaddr_in cli_addr;
int cli_addr_len;
ssize_t nbytes;
openlog("btimed", LOG_PID, LOG_USER);
/* Running out of (x)inetd the socket was duped onto stdin. */
sd = fileno(stdin);
/* We want to exit after 30 seconds of inactivity */
alarm(30);
/* Generate the standard btime message */
memset(outmsg, 0, BTIME_MSGLEN);
sprintf(outmsg, "%u\n", get_btime());
for (;;) {
memset(&cli_addr, 0, sizeof cli_addr);
cli_addr_len = sizeof cli_addr;
nbytes = recvfrom(sd, &inmsg, BTIME_MSGLEN, MSG_WAITALL,
(struct sockaddr *)&cli_addr, &cli_addr_len);
sendto(sd, &outmsg, BTIME_MSGLEN, MSG_DONTWAIT,
(struct sockaddr *)&cli_addr, cli_addr_len);
/* We want to exit after 30 seconds of inactivity */
alarm(30);
}
return 0;
}
/*
*---------------------------------------------------------------------------
*
* get_btime --
*
* Return machine's boot time.
*
* Returns:
* 0 on failure
* non-zero on success.
*
*---------------------------------------------------------------------------
*/
static unsigned int
get_btime(void)
{
FILE *statf;
char line[1024];
unsigned int btime = 0;
if ((statf = fopen("/proc/stat", "r")) == NULL) {
syslog(LOG_ERR, "/proc/stat open failure: %s\n",
strerror(errno));
exit(1);
}
while (fgets(line, 1024, statf) != NULL) {
if (strstr(line, "btime") != NULL) {
sscanf(line, "%*s%u", &btime);
}
}
fclose(statf);
return btime;
}
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