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#include "filelock.h"
#include "mio.h"
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_SYS_FILE_H
#include <sys/file.h>
#endif
#include <errno.h>
#include "liblock/config.h"
#include "liblock/liblock.h"
void FileLock::cleanup()
{
UnLock();
}
void FileLock::forked()
{
UnLock();
}
FileLock::FileLock() : fd(-1)
{
}
FileLock::~FileLock()
{
UnLock();
}
void FileLock::Lock(const char *filename)
{
UnLock();
if ((fd=mopen(filename, O_CREAT | O_WRONLY, 0600)) < 0)
throw "Unable to create flock file.";
do_filelock(fd);
}
void FileLock::do_filelock(int fd)
{
int flockrc;
while ((flockrc=ll_lock_ex(fd)) < 0 && errno == EINTR)
;
if (flockrc < 0)
{
struct stat stat_buf;
// FreeBSD has problems locking /dev/null. Presume that if
// you're writing to a device file, you know what you're doing.
if (fstat(fd, &stat_buf) >= 0 && (
S_ISREG(stat_buf.st_mode) || S_ISDIR(stat_buf.st_mode)))
{
return;
}
throw "flock() failed.";
}
}
void FileLock::UnLock()
{
if (fd >= 0)
{
mclose(fd);
fd= -1;
}
}
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