*** empty log message ***

[gnu-emacs] / src / filelock.c

diff --git a/src/filelock.c b/src/filelock.c
index 6882443c1e578bcd07b580eec3fea8558ccef43b..44db9722f91048c165114f79b72731eb2b60b6c4 100644 (file)
--- a/src/filelock.c
+++ b/src/filelock.c
@@ -1,5 +1,6 @@
 /* Lock files for editing.
-   Copyright (C) 1985, 86, 87, 93, 94, 96, 98, 1999 Free Software Foundation, Inc.
+   Copyright (C) 1985, 86, 87, 93, 94, 96, 98, 1999, 2000
+   Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
@@ -19,14 +20,11 @@ the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 Boston, MA 02111-1307, USA.  */
 
 
+#include <config.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <signal.h>
-#include <config.h>
 #include <stdio.h>
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
 
 #ifdef VMS
 #include "vms-pwd.h"
@@ -35,33 +33,32 @@ Boston, MA 02111-1307, USA.  */
 #endif /* not VMS */
 
 #include <sys/file.h>
-#ifdef USG
+#ifdef HAVE_FCNTL_H
 #include <fcntl.h>
+#endif
+#ifdef HAVE_STRING_H
 #include <string.h>
-#endif /* USG */
+#endif
 
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 
 #ifdef __FreeBSD__
-#include <sys/time.h>
-#include <sys/types.h>
 #include <sys/sysctl.h>
 #endif /* __FreeBSD__ */
 
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+
 #include "lisp.h"
 #include "buffer.h"
 #include "charset.h"
 #include "coding.h"
 #include "systime.h"
 
-#include <time.h>
-#include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
-
 /* The directory for writing temporary files.  */
 
 Lisp_Object Vtemporary_file_directory;
@@ -123,6 +120,10 @@ static int boot_time_initialized;
 
 extern Lisp_Object Vshell_file_name;
 
+#ifdef BOOT_TIME
+static void get_boot_time_1 P_ ((char *, int));
+#endif
+
 static time_t
 get_boot_time ()
 {
@@ -202,9 +203,15 @@ get_boot_time ()
          if (! NILP (Ffile_exists_p (tempname)))
            {
              Lisp_Object args[6];
-             tempname = Fexpand_file_name (build_string ("wtmp"),
+
+             /* 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.  */
+             tempname = Fexpand_file_name (build_string ("wt"),
                                            Vtemporary_file_directory);
-             tempname = Fmake_temp_name (tempname);
+             tempname = make_temp_name (tempname, 1);
              args[0] = Vshell_file_name;
              args[1] = Qnil;
              args[2] = Qnil;
@@ -244,6 +251,7 @@ get_boot_time ()
    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 (filename, newest)
      char *filename;
      int newest;
@@ -255,11 +263,11 @@ get_boot_time_1 (filename, newest)
     {
       /* On some versions of IRIX, opening a nonexistent file name
         is likely to crash in the utmp routines.  */
-      desc = open (filename, O_RDONLY);
+      desc = emacs_open (filename, O_RDONLY, 0);
       if (desc < 0)
        return;
 
-      close (desc);
+      emacs_close (desc);
 
       utmpname (filename);
     }
@@ -309,9 +317,11 @@ typedef struct
 
 
 /* Write the name of the lock file for FN into LFNAME.  Length will be
-   that of FN plus two more for the leading `.#' plus one for the null.  */
+   that of FN plus two more for the leading `.#' plus 1 for the
+   trailing period plus one for the digit after it plus one for the
+   null.  */
 #define MAKE_LOCK_NAME(lock, file) \
-  (lock = (char *) alloca (STRING_BYTES (XSTRING (file)) + 2 + 1), \
+  (lock = (char *) alloca (STRING_BYTES (XSTRING (file)) + 2 + 1 + 1 + 1), \
    fill_in_lock_file_name (lock, (file)))
 
 static void
@@ -320,6 +330,8 @@ fill_in_lock_file_name (lockfile, fn)
      register Lisp_Object fn;
 {
   register char *p;
+  struct stat st;
+  int count = 0;
 
   strcpy (lockfile, XSTRING (fn)->data);
 
@@ -332,6 +344,18 @@ fill_in_lock_file_name (lockfile, fn)
   /* Insert the `.#'.  */
   p[1] = '.';
   p[2] = '#';
+
+  p = p + strlen (p);
+
+  while (lstat (lockfile, &st) == 0 && !S_ISLNK (st.st_mode))
+    {
+      if (count > 9)
+       {
+         *p = '\0';
+         return;
+       }
+      sprintf (p, ".%d", count++);
+    }
 }
 
 /* Lock the lock file named LFNAME.
@@ -558,6 +582,7 @@ lock_file (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
@@ -577,7 +602,6 @@ lock_file (fn)
      visited.  */
   {
     register Lisp_Object subject_buf;
-    struct gcpro gcpro1;
 
     subject_buf = get_truename_buffer (orig_fn);
 
@@ -637,12 +661,7 @@ unlock_all_files ()
       b = XBUFFER (XCDR (XCAR (tail)));
       if (STRINGP (b->file_truename) && BUF_SAVE_MODIFF (b) < BUF_MODIFF (b))
        {
-         register char *lfname;
-
-         MAKE_LOCK_NAME (lfname, b->file_truename);
-
-         if (current_lock_owner (0, lfname) == 2)
-           unlink (lfname);
+         unlock_file(b->file_truename);
        }
     }
 }
@@ -688,7 +707,7 @@ unlock_buffer (buffer)
     unlock_file (buffer->file_truename);
 }
 
-DEFUN ("file-locked-p", Ffile_locked_p, Sfile_locked_p, 0, 1, 0,
+DEFUN ("file-locked-p", Ffile_locked_p, Sfile_locked_p, 1, 1, 0,
   "Return nil if the FILENAME is not locked,\n\
 t if it is locked by you, else a string of the name of the locker.")
   (filename)