Remove the build-time option CLASH_DETECTION

Every platform supports it, and the runtime option `create-lockfiles'
replaces it.

* configure.ac (CLASH_DETECTION): Remove option.

* lisp/files.el (lock-buffer, unlock-buffer, file-locked-p):
Remove fallback aliases, since they are always defined now.

* src/buffer.c (Frestore_buffer_modified_p, Fkill_buffer):
* src/emacs.c (shut_down_emacs):
* src/fileio.c (Finsert_file_contents, write_region):
* src/filelock.c (top-level, syms_of_filelock):
* src/insdel.c (prepare_to_modify_buffer_1):
CLASH_DETECTION is always defined now.

* admin/CPP-DEFINES: Remove CLASH_DETECTION.

1 files changed, 0 insertions, 14 deletions

diff --git a/src/fileio.c b/src/fileio.c
index fb0a33b39db..152b7a8a8ed 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -4079,13 +4079,11 @@ by calling `format-decode', which see.  */)
 
   if (NILP (visit) && total > 0)
     {
-#ifdef CLASH_DETECTION
       if (!NILP (BVAR (current_buffer, file_truename))
           /* Make binding buffer-file-name to nil effective.  */
           && !NILP (BVAR (current_buffer, filename))
           && SAVE_MODIFF >= MODIFF)
         we_locked_file = 1;
-#endif /* CLASH_DETECTION */
       prepare_to_modify_buffer (GPT, GPT, NULL);
     }
 
@@ -4185,10 +4183,8 @@ by calling `format-decode', which see.  */)
 
   if (inserted == 0)
     {
-#ifdef CLASH_DETECTION
       if (we_locked_file)
         unlock_file (BVAR (current_buffer, file_truename));
-#endif
       Vdeactivate_mark = old_Vdeactivate_mark;
     }
   else
@@ -4337,14 +4333,12 @@ by calling `format-decode', which see.  */)
       SAVE_MODIFF = MODIFF;
       BUF_AUTOSAVE_MODIFF (current_buffer) = MODIFF;
       XSETFASTINT (BVAR (current_buffer, save_length), Z - BEG);
-#ifdef CLASH_DETECTION
       if (NILP (handler))
         {
           if (!NILP (BVAR (current_buffer, file_truename)))
             unlock_file (BVAR (current_buffer, file_truename));
           unlock_file (filename);
         }
-#endif /* CLASH_DETECTION */
       if (not_regular)
         xsignal2 (Qfile_error,
                   build_string ("not a regular file"), orig_filename);
@@ -4814,13 +4808,11 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename,
   if (!STRINGP (start) && !NILP (BVAR (current_buffer, selective_display)))
     coding.mode |= CODING_MODE_SELECTIVE_DISPLAY;
 
-#ifdef CLASH_DETECTION
   if (open_and_close_file && !auto_saving)
     {
       lock_file (lockname);
       file_locked = 1;
     }
-#endif /* CLASH_DETECTION */
 
   encoded_filename = ENCODE_FILE (filename);
   fn = SSDATA (encoded_filename);
@@ -4842,10 +4834,8 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename,
       if (desc < 0)
         {
           int open_errno = errno;
-#ifdef CLASH_DETECTION
           if (file_locked)
             unlock_file (lockname);
-#endif /* CLASH_DETECTION */
           UNGCPRO;
           report_file_errno ("Opening output file", filename, open_errno);
         }
@@ -4860,10 +4850,8 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename,
       if (ret < 0)
         {
           int lseek_errno = errno;
-#ifdef CLASH_DETECTION
           if (file_locked)
             unlock_file (lockname);
-#endif /* CLASH_DETECTION */
           UNGCPRO;
           report_file_errno ("Lseek error", filename, lseek_errno);
         }
@@ -5006,10 +4994,8 @@ write_region (Lisp_Object start, Lisp_Object end, Lisp_Object filename,
 
   unbind_to (count, Qnil);
 
-#ifdef CLASH_DETECTION
   if (file_locked)
     unlock_file (lockname);
-#endif /* CLASH_DETECTION */
 
   /* Do this before reporting IO error
      to avoid a "file has changed on disk" warning on