/* Lock files for editing.
- Copyright (C) 1985-1987, 1993-1994, 1996, 1998-2011
- Free Software Foundation, Inc.
+ Copyright (C) 1985-1987, 1993-1994, 1996, 1998-2013 Free Software
+ Foundation, Inc.
This file is part of GNU Emacs.
#include <sys/stat.h>
#include <signal.h>
#include <stdio.h>
-#include <setjmp.h>
#ifdef HAVE_PWD_H
#include <pwd.h>
#include <errno.h>
#include "lisp.h"
-#include "buffer.h"
#include "character.h"
+#include "buffer.h"
#include "coding.h"
#include "systime.h"
/* Return the time of the last system boot. */
static time_t boot_time;
-static int boot_time_initialized;
+static bool boot_time_initialized;
#ifdef BOOT_TIME
-static void get_boot_time_1 (const char *, int);
+static void get_boot_time_1 (const char *, bool);
#endif
static time_t
{
char cmd_string[sizeof WTMP_FILE ".19.gz"];
Lisp_Object tempname, filename;
- int delete_flag = 0;
+ bool delete_flag = 0;
filename = Qnil;
- sprintf (cmd_string, "%s.%d", WTMP_FILE, counter);
- tempname = build_string (cmd_string);
+ tempname = make_formatted_string
+ (cmd_string, "%s.%d", WTMP_FILE, counter);
if (! NILP (Ffile_exists_p (tempname)))
filename = tempname;
else
{
- sprintf (cmd_string, "%s.%d.gz", WTMP_FILE, counter);
- tempname = build_string (cmd_string);
+ tempname = make_formatted_string (cmd_string, "%s.%d.gz",
+ WTMP_FILE, counter);
if (! NILP (Ffile_exists_p (tempname)))
{
Lisp_Object args[6];
If FILENAME is zero, use the same file as before;
if no FILENAME has ever been specified, this is the utmp file.
- Use the newest reboot record if NEWEST is nonzero,
+ Use the newest reboot record if NEWEST,
the first reboot record otherwise.
Ignore all reboot records on or before BOOT_TIME.
Success is indicated by setting BOOT_TIME to a larger value. */
void
-get_boot_time_1 (const char *filename, int newest)
+get_boot_time_1 (const char *filename, bool newest)
{
struct utmp ut, *utp;
int desc;
trailing period plus one for the digit after it plus one for the
null. */
#define MAKE_LOCK_NAME(lock, file) \
- (lock = (char *) alloca (SBYTES (file) + 2 + 1 + 1 + 1), \
+ (lock = alloca (SBYTES (file) + 2 + 1 + 1 + 1), \
fill_in_lock_file_name (lock, (file)))
static void
fill_in_lock_file_name (register char *lockfile, register Lisp_Object fn)
{
+ ptrdiff_t length = SBYTES (fn);
register char *p;
struct stat st;
int count = 0;
/* Shift the nondirectory part of the file name (including the null)
right two characters. Here is one of the places where we'd have to
do something to support 14-character-max file names. */
- for (p = lockfile + strlen (lockfile); p != lockfile && *p != '/'; p--)
+ for (p = lockfile + length; p != lockfile && *p != '/'; p--)
p[2] = *p;
/* Insert the `.#'. */
p[1] = '.';
p[2] = '#';
- p = p + strlen (p);
+ p = p + length + 2;
while (lstat (lockfile, &st) == 0 && !S_ISLNK (st.st_mode))
{
}
/* Lock the lock file named LFNAME.
- If FORCE is nonzero, we do so even if it is already locked.
- Return 1 if successful, 0 if not. */
+ If FORCE, do so even if it is already locked.
+ Return true if successful. */
-static int
-lock_file_1 (char *lfname, int force)
+static bool
+lock_file_1 (char *lfname, bool force)
{
- register int err;
- printmax_t boot, pid;
- const char *user_name;
- const char *host_name;
- char *lock_info_str;
- ptrdiff_t lock_info_size;
+ int err;
int symlink_errno;
USE_SAFE_ALLOCA;
/* Call this first because it can GC. */
- boot = get_boot_time ();
-
- if (STRINGP (Fuser_login_name (Qnil)))
- user_name = SSDATA (Fuser_login_name (Qnil));
- else
- user_name = "";
- if (STRINGP (Fsystem_name ()))
- host_name = SSDATA (Fsystem_name ());
- else
- host_name = "";
- lock_info_size = (strlen (user_name) + strlen (host_name)
- + 2 * INT_STRLEN_BOUND (printmax_t)
- + sizeof "@.:");
- SAFE_ALLOCA (lock_info_str, char *, lock_info_size);
- pid = getpid ();
+ printmax_t boot = get_boot_time ();
+
+ Lisp_Object luser_name = Fuser_login_name (Qnil);
+ char const *user_name = STRINGP (luser_name) ? SSDATA (luser_name) : "";
+ Lisp_Object lhost_name = Fsystem_name ();
+ char const *host_name = STRINGP (lhost_name) ? SSDATA (lhost_name) : "";
+ ptrdiff_t lock_info_size = (strlen (user_name) + strlen (host_name)
+ + 2 * INT_STRLEN_BOUND (printmax_t)
+ + sizeof "@.:");
+ char *lock_info_str = SAFE_ALLOCA (lock_info_size);
+ printmax_t pid = getpid ();
esprintf (lock_info_str, boot ? "%s@%s.%"pMd":%"pMd : "%s@%s.%"pMd,
user_name, host_name, pid, boot);
return err == 0;
}
-/* Return 1 if times A and B are no more than one second apart. */
+/* Return true if times A and B are no more than one second apart. */
-static int
+static bool
within_one_second (time_t a, time_t b)
{
return (a - b >= -1 && a - b <= 1);
return -1;
}
len = at - lfinfo;
- owner->user = (char *) xmalloc (len + 1);
+ owner->user = xmalloc (len + 1);
memcpy (owner->user, lfinfo, len);
owner->user[len] = 0;
/* The host is everything in between. */
len = dot - at - 1;
- owner->host = (char *) xmalloc (len + 1);
+ owner->host = xmalloc (len + 1);
memcpy (owner->host, at + 1, len);
owner->host[len] = 0;
static int
lock_if_free (lock_info_type *clasher, register char *lfname)
{
- while (lock_file_1 (lfname, 0) == 0)
+ while (! lock_file_1 (lfname, 0))
{
int locker;
struct gcpro gcpro1;
USE_SAFE_ALLOCA;
+ /* Don't do locking if the user has opted out. */
+ if (! create_lockfiles)
+ return;
+
/* Don't do locking while dumping Emacs.
Uncompressing wtmp files uses call-process, which does not work
in an uninitialized Emacs. */
locker_size = (strlen (lock_info.user) + strlen (lock_info.host)
+ INT_STRLEN_BOUND (printmax_t)
+ sizeof "@ (pid )");
- SAFE_ALLOCA (locker, char *, locker_size);
+ locker = SAFE_ALLOCA (locker_size);
pid = lock_info.pid;
esprintf (locker, "%s@%s (pid %"pMd")",
lock_info.user, lock_info.host, pid);
b = XBUFFER (XCDR (XCAR (tail)));
if (STRINGP (BVAR (b, file_truename)) && BUF_SAVE_MODIFF (b) < BUF_MODIFF (b))
{
- unlock_file(BVAR (b, file_truename));
+ unlock_file (BVAR (b, file_truename));
}
}
}
return ret;
}
-\f
-/* Initialization functions. */
-
-void
-init_filelock (void)
-{
- boot_time = 0;
- boot_time_initialized = 0;
-}
#endif /* CLASH_DETECTION */
doc: /* The directory for writing temporary files. */);
Vtemporary_file_directory = Qnil;
+ DEFVAR_BOOL ("create-lockfiles", create_lockfiles,
+ doc: /* Non-nil means use lockfiles to avoid editing collisions. */);
+ create_lockfiles = 1;
+
#ifdef CLASH_DETECTION
defsubr (&Sunlock_buffer);
defsubr (&Slock_buffer);