void
lock_file (Lisp_Object fn)
{
register Lisp_Object attack, orig_fn, encoded_fn;
register char *lfname, *locker;
lock_info_type lock_info;
struct gcpro gcpro1;
/* Don't do locking while dumping Emacs.
Uncompressing wtmp files uses call-process, which does not work
in an uninitialized Emacs. */
if (! NILP (Vpurify_flag))
return;
orig_fn = fn;
GCPRO1 (fn);
fn = Fexpand_file_name (fn, Qnil);
encoded_fn = ENCODE_FILE (fn);
/* Create the name of the lock-file for file fn */
MAKE_LOCK_NAME (lfname, encoded_fn);
/* See if this file is visited and has changed on disk since it was
visited. */
{
register Lisp_Object subject_buf;
subject_buf = get_truename_buffer (orig_fn);
if (!NILP (subject_buf)
&& NILP (Fverify_visited_file_modtime (subject_buf))
&& !NILP (Ffile_exists_p (fn)))
call1 (intern ("ask-user-about-supersession-threat"), fn);
}
UNGCPRO;
/* Try to lock the lock. */
if (lock_if_free (&lock_info, lfname) <= 0)
/* Return now if we have locked it, or if lock creation failed */
return;
/* Else consider breaking the lock */
locker = (char *) alloca (strlen (lock_info.user) + strlen (lock_info.host)
+ LOCK_PID_MAX + 9);
sprintf (locker, "%s@%s (pid %lu)", lock_info.user, lock_info.host,
lock_info.pid);
FREE_LOCK_INFO (lock_info);
attack = call2 (intern ("ask-user-about-lock"), fn, build_string (locker));
if (!NILP (attack))
/* User says take the lock */
{
lock_file_1 (lfname, 1);
return;
}
/* User says ignore the lock */
}
static time_t
get_boot_time (void)
{
#if defined (BOOT_TIME)
int counter;
#endif
if (boot_time_initialized)
return boot_time;
boot_time_initialized = 1;
#if defined (CTL_KERN) && defined (KERN_BOOTTIME)
{
int mib[2];
size_t size;
struct timeval boottime_val;
mib[0] = CTL_KERN;
mib[1] = KERN_BOOTTIME;
size = sizeof (boottime_val);
if (sysctl (mib, 2, &boottime_val, &size, NULL, 0) >= 0)
{
boot_time = boottime_val.tv_sec;
return boot_time;
}
}
#endif /* defined (CTL_KERN) && defined (KERN_BOOTTIME) */
if (BOOT_TIME_FILE)
{
struct stat st;
if (stat (BOOT_TIME_FILE, &st) == 0)
{
boot_time = st.st_mtime;
return boot_time;
}
}
#if defined (BOOT_TIME)
#ifndef CANNOT_DUMP
/* The utmp routines maintain static state.
Don't touch that state unless we are initialized,
since it might not survive dumping. */
if (! initialized)
return boot_time;
#endif /* not CANNOT_DUMP */
/* Try to get boot time from utmp before wtmp,
since utmp is typically much smaller than wtmp.
Passing a null pointer causes get_boot_time_1
to inspect the default file, namely utmp. */
get_boot_time_1 (0, 0);
if (boot_time)
return boot_time;
/* Try to get boot time from the current wtmp file. */
get_boot_time_1 (WTMP_FILE, 1);
/* If we did not find a boot time in wtmp, look at wtmp, and so on. */
for (counter = 0; counter < 20 && ! boot_time; counter++)
{
char cmd_string[sizeof WTMP_FILE ".19.gz"];
Lisp_Object tempname, filename;
bool delete_flag = 0;
filename = Qnil;
tempname = make_formatted_string
(cmd_string, "%s.%d", WTMP_FILE, counter);
if (! NILP (Ffile_exists_p (tempname)))
filename = tempname;
else
{
tempname = make_formatted_string (cmd_string, "%s.%d.gz",
WTMP_FILE, counter);
if (! NILP (Ffile_exists_p (tempname)))
{
Lisp_Object args[6];
/* The utmp functions on mescaline.gnu.org accept only
file names up to 8 characters long. Choose a 2
character long prefix, and call make_temp_file with
second arg non-zero, so that it will add not more
than 6 characters to the prefix. */
filename = Fexpand_file_name (build_string ("wt"),
Vtemporary_file_directory);
filename = make_temp_name (filename, 1);
args[0] = build_string ("gzip");
args[1] = Qnil;
args[2] = list2 (QCfile, filename);
args[3] = Qnil;
args[4] = build_string ("-cd");
args[5] = tempname;
Fcall_process (6, args);
delete_flag = 1;
}
}
if (! NILP (filename))
{
get_boot_time_1 (SSDATA (filename), 1);
if (delete_flag)
unlink (SSDATA (filename));
}
}
return boot_time;
#else
return 0;
#endif
}
