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/* ISC license. */
#include <skalibs/nonposix.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/socket.h>
#include <skalibs/djbunix.h>
#include <skalibs/socket.h>
int ipc_bind_reuse_lock (int s, char const *p, int *fdlock)
{
unsigned int opt = 1 ;
size_t len = strlen(p) ;
int fd ;
int r ;
char lockname[len + 6] ;
memcpy(lockname, p, len) ;
memcpy(lockname + len, ".lock", 6) ;
fd = open3(lockname, O_WRONLY | O_NONBLOCK | O_CREAT | O_CLOEXEC, 0600) ;
if (fd < 0) return -1 ;
r = fd_lock(fd, 1, 1) ;
if (r < 0) return -1 ;
if (!r) return (errno = EBUSY, -1) ;
r = errno ;
setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt) ;
errno = r ;
unlink_void(p) ;
if (ipc_bind(s, p) < 0) return -1 ;
*fdlock = fd ;
return 0 ;
}
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