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/* ISC license. */
#include <skalibs/sysdeps.h>
#ifndef SKALIBS_HASSOPEERCRED
#error "The SO_PEERCRED option to getsockopt() is required."
#endif
#include <skalibs/nonposix.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <errno.h>
#include <utmpx.h>
#include <skalibs/allreadwrite.h>
#include <skalibs/strerr.h>
#ifndef UT_NAMESIZE
#define UT_NAMESIZE 32
#endif
#ifndef UT_HOSTSIZE
#define UT_HOSTSIZE 256
#endif
int main (void)
{
struct utmpx *utx ;
struct ucred client ;
socklen_t len = sizeof(client) ;
ssize_t r ;
char c ;
close(1) ;
if (getsockopt(0, SOL_SOCKET, SO_PEERCRED, &client, &len) == -1)
strerr_diefu1sys(111, "getsockopt") ;
/* Only take connections from root. */
if (client.uid) return 1 ;
/* Wait for the client to die. */
r = fd_read(0, &c, 1) ;
if (r < 0) strerr_diefu1sys(111, "read from stdin") ;
if (r) strerr_dief1x(2, "client attempted to write") ;
/* Clean up utmpx record for the client's pid, then exit. */
for (;;)
{
errno = 0 ;
utx = getutxent() ;
if (!utx) break ;
if (utx->ut_pid == client.pid) goto gotit ;
}
if (errno) strerr_diefu1sys(111, "getutxent") ;
return 0 ;
gotit:
utx->ut_type = DEAD_PROCESS ;
memset(utx->ut_user, 0, UT_NAMESIZE) ;
memset(utx->ut_host, 0, UT_HOSTSIZE) ;
utx->ut_tv.tv_sec = 0 ;
utx->ut_tv.tv_usec = 0 ;
setutxent() ;
if (!pututxline(utx)) strerr_diefu1sys(111, "pututxline") ;
return 0 ;
}
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