To: vim-dev@vim.org

To: [email protected]
Subject: patch 5.4p.5
Fcc: outbox
From: Bram Moolenaar <[email protected]>
------------

Another nasty autocommand problem. It appears more people are using
autocommands these days. It requires a radical change to how autocommands are
executed. But not right now.

Patch 5.4p.5
Problem: When changing buffers in a BufDelete autocommand, there could be
ml_line errors and/or a crash. (Schandl) Was caused by deleting
the current buffer.
Solution: When the buffer to be deleted unexpectedly becomes the current
buffer, don't delete it.
Also added a check for this in test13.
Files: src/buffer.c, src/testdir/test13.in, src/testdir/test13.ok

*** ../vim-5.4p/src/buffer.c Mon Jul 19 11:08:56 1999
--- src/buffer.c Tue Jul 20 13:17:13 1999
***************
*** 185,190 ****
--- 185,194 ----
int free_buf;
int del_buf;
{
+ #ifdef AUTOCMD
+ int is_curbuf;
+ #endif
+
if (buf->b_nwindows > 0)
--buf->b_nwindows;
if (buf->b_nwindows == 0 && win != NULL)
***************
*** 218,226 ****
* Free all things allocated for this buffer.
* Also calls the "BufDelete" autocommands when del_buf is TRUE.
*/
buf_freeall(buf, del_buf);
! if (!buf_valid(buf)) /* autocommands may delete the buffer */
return;

/*
* Remove the buffer from the list.
--- 222,242 ----
* Free all things allocated for this buffer.
* Also calls the "BufDelete" autocommands when del_buf is TRUE.
*/
+ #ifdef AUTOCMD
+ is_curbuf = (buf == curbuf);
+ #endif
buf_freeall(buf, del_buf);
! #ifdef AUTOCMD
! /*
! * Autocommands may have deleted the buffer.
! * It's possible that autocommands change curbuf to the one being deleted.
! * This might cause curbuf to be deleted unexpectedly. But in some cases
! * it's OK to delete the curbuf, because a new one is obtained anyway.
! * Therefore only return if curbuf changed to the deleted buffer.
! */
! if (!buf_valid(buf) || (buf == curbuf && !is_curbuf))
return;
+ #endif

/*
* Remove the buffer from the list.
***************
*** 267,276 ****
/*ARGSUSED*/
void
buf_freeall(buf, del_buf)
! BUF *buf;
! int del_buf; /* buffer is going to be deleted */
{
#ifdef AUTOCMD
apply_autocmds(EVENT_BUFUNLOAD, buf->b_fname, buf->b_fname, FALSE, buf);
if (!buf_valid(buf)) /* autocommands may delete the buffer */
return;
--- 283,294 ----
/*ARGSUSED*/
void
buf_freeall(buf, del_buf)
! BUF *buf;
! int del_buf; /* buffer is going to be deleted */
{
#ifdef AUTOCMD
+ int is_curbuf = (buf == curbuf);
+
apply_autocmds(EVENT_BUFUNLOAD, buf->b_fname, buf->b_fname, FALSE, buf);
if (!buf_valid(buf)) /* autocommands may delete the buffer */
return;
***************
*** 280,285 ****
--- 298,311 ----
if (!buf_valid(buf)) /* autocommands may delete the buffer */
return;
}
+ /*
+ * It's possible that autocommands change curbuf to the one being deleted.
+ * This might cause curbuf to be deleted unexpectedly. But in some cases
+ * it's OK to delete the curbuf, because a new one is obtained anyway.
+ * Therefore only return if curbuf changed to the deleted buffer.
+ */
+ if (buf == curbuf && !is_curbuf)
+ return;
#endif
#ifdef HAVE_TCL
tcl_buffer_free(buf);
*** ../vim-5.4p/src/testdir/test13.in Mon Jul 19 11:08:50 1999
--- src/testdir/test13.in Tue Jul 20 13:31:27 1999
***************
*** 7,12 ****
--- 7,15 ----
Also test deleting the buffer on a Unload event. If this goes wrong there
will be the ATTENTION prompt.

+ Also test changing buffers in a BufDel autocommand. If this goes wrong there
+ are ml_line errors and/or a Crash.
+
STARTTEST
:/^start of testfile/,/^end of testfile/w! Xtestje1
:/^start of testfile/,/^end of testfile/w! Xtestje2
***************
*** 36,41 ****
--- 39,51 ----
:e Xtestje2
:sp Xtestje1
:e
+ :w >>test.out
+ :au!
+ :only
+ :e Xtestje1
+ :bdel Xtestje2 Xtestje3 test.out test13.in
+ :au BufDelete Xtestje1 buf Xtestje1
+ :bd
:w >>test.out
:!rm -rf Xtestje*
:qa!
*** ../vim-5.4p/src/testdir/test13.ok Mon Jul 19 11:08:50 1999
--- src/testdir/test13.ok Tue Jul 20 13:35:40 1999
***************
*** 22,24 ****
--- 22,30 ----
contents
contents
end of testfile
+ start of testfile
+ testje1
+ contents
+ contents
+ contents
+ end of testfile

--
hundred-and-one symptoms of being an internet addict:
174. You know what a listserv is.

--/-/---- Bram Moolenaar ---- [email protected] ---- [email protected] ---\-\--
\ \ www.vim.org/iccf www.moolenaar.net www.vim.org / /