To: vim-dev@vim.org
Subject: About patch 7.1.130
Fcc: outbox
From: Bram Moolenaar <Bram@moolenaar.net>
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------------
Patch 7.1.130
Problem: Crash with specific order of undo and redo. (A.Politz)
Solution: Clear and adjust pointers properly. Add u_check() for debugging.
Files: src/undo.c, src/structs.h
*** ../vim-7.1.129/src/undo.c Thu May 10 20:01:43 2007
--- src/undo.c Mon Oct 1 22:49:16 2007
***************
*** 76,81 ****
--- 76,87 ----
* buffer is unloaded.
*/
+ /* Uncomment the next line for including the u_check() function. This warns
+ * for errors in the debug information. */
+ /* #define U_DEBUG 1 */
+ #define UH_MAGIC 0x18dade /* value for uh_magic when in use */
+ #define UE_MAGIC 0xabc123 /* value for ue_magic when in use */
+
#include "vim.h"
/* See below: use malloc()/free() for memory management. */
***************
*** 113,118 ****
--- 119,213 ----
*/
static int undo_undoes = FALSE;
+ #ifdef U_DEBUG
+ /*
+ * Check the undo structures for being valid. Print a warning when something
+ * looks wrong.
+ */
+ static int seen_b_u_curhead;
+ static int seen_b_u_newhead;
+ static int header_count;
+
+ static void
+ u_check_tree(u_header_T *uhp,
+ u_header_T *exp_uh_next,
+ u_header_T *exp_uh_alt_prev)
+ {
+ u_entry_T *uep;
+
+ if (uhp == NULL)
+ return;
+ ++header_count;
+ if (uhp == curbuf->b_u_curhead && ++seen_b_u_curhead > 1)
+ {
+ EMSG("b_u_curhead found twice (looping?)");
+ return;
+ }
+ if (uhp == curbuf->b_u_newhead && ++seen_b_u_newhead > 1)
+ {
+ EMSG("b_u_newhead found twice (looping?)");
+ return;
+ }
+
+ if (uhp->uh_magic != UH_MAGIC)
+ EMSG("uh_magic wrong (may be using freed memory)");
+ else
+ {
+ /* Check pointers back are correct. */
+ if (uhp->uh_next != exp_uh_next)
+ {
+ EMSG("uh_next wrong");
+ smsg((char_u *)"expected: 0x%x, actual: 0x%x",
+ exp_uh_next, uhp->uh_next);
+ }
+ if (uhp->uh_alt_prev != exp_uh_alt_prev)
+ {
+ EMSG("uh_alt_prev wrong");
+ smsg((char_u *)"expected: 0x%x, actual: 0x%x",
+ exp_uh_alt_prev, uhp->uh_alt_prev);
+ }
+
+ /* Check the undo tree at this header. */
+ for (uep = uhp->uh_entry; uep != NULL; uep = uep->ue_next)
+ {
+ if (uep->ue_magic != UE_MAGIC)
+ {
+ EMSG("ue_magic wrong (may be using freed memory)");
+ break;
+ }
+ }
+
+ /* Check the next alt tree. */
+ u_check_tree(uhp->uh_alt_next, uhp->uh_next, uhp);
+
+ /* Check the next header in this branch. */
+ u_check_tree(uhp->uh_prev, uhp, NULL);
+ }
+ }
+
+ void
+ u_check(int newhead_may_be_NULL)
+ {
+ seen_b_u_newhead = 0;
+ seen_b_u_curhead = 0;
+ header_count = 0;
+
+ u_check_tree(curbuf->b_u_oldhead, NULL, NULL);
+
+ if (seen_b_u_newhead == 0 && curbuf->b_u_oldhead != NULL
+ && !(newhead_may_be_NULL && curbuf->b_u_newhead == NULL))
+ EMSGN("b_u_newhead invalid: 0x%x", curbuf->b_u_newhead);
+ if (curbuf->b_u_curhead != NULL && seen_b_u_curhead == 0)
+ EMSGN("b_u_curhead invalid: 0x%x", curbuf->b_u_curhead);
+ if (header_count != curbuf->b_u_numhead)
+ {
+ EMSG("b_u_numhead invalid");
+ smsg((char_u *)"expected: %ld, actual: %ld",
+ (long)header_count, (long)curbuf->b_u_numhead);
+ }
+ }
+ #endif
+
/*
* Save the current line for both the "u" and "U" command.
* Returns OK or FAIL.
***************
*** 243,248 ****
--- 338,346 ----
if (!undo_allowed())
return FAIL;
+ #ifdef U_DEBUG
+ u_check(FALSE);
+ #endif
#ifdef FEAT_NETBEANS_INTG
/*
* Netbeans defines areas that cannot be modified. Bail out here when
***************
*** 294,299 ****
--- 392,400 ----
uhp = (u_header_T *)U_ALLOC_LINE((unsigned)sizeof(u_header_T));
if (uhp == NULL)
goto nomem;
+ #ifdef U_DEBUG
+ uhp->uh_magic = UH_MAGIC;
+ #endif
}
else
uhp = NULL;
***************
*** 316,323 ****
{
u_header_T *uhfree = curbuf->b_u_oldhead;
! /* If there is no branch only free one header. */
! if (uhfree->uh_alt_next == NULL)
u_freeheader(curbuf, uhfree, &old_curhead);
else
{
--- 417,427 ----
{
u_header_T *uhfree = curbuf->b_u_oldhead;
! if (uhfree == old_curhead)
! /* Can't reconnect the branch, delete all of it. */
! u_freebranch(curbuf, uhfree, &old_curhead);
! else if (uhfree->uh_alt_next == NULL)
! /* There is no branch, only free one header. */
u_freeheader(curbuf, uhfree, &old_curhead);
else
{
***************
*** 326,331 ****
--- 430,438 ----
uhfree = uhfree->uh_alt_next;
u_freebranch(curbuf, uhfree, &old_curhead);
}
+ #ifdef U_DEBUG
+ u_check(TRUE);
+ #endif
}
if (uhp == NULL) /* no undo at all */
***************
*** 478,483 ****
--- 585,593 ----
uep = (u_entry_T *)U_ALLOC_LINE((unsigned)sizeof(u_entry_T));
if (uep == NULL)
goto nomem;
+ #ifdef U_DEBUG
+ uep->ue_magic = UE_MAGIC;
+ #endif
uep->ue_size = size;
uep->ue_top = top;
***************
*** 525,530 ****
--- 635,643 ----
curbuf->b_u_synced = FALSE;
undo_undoes = FALSE;
+ #ifdef U_DEBUG
+ u_check(FALSE);
+ #endif
return OK;
nomem:
***************
*** 955,960 ****
--- 1068,1076 ----
int empty_buffer; /* buffer became empty */
u_header_T *curhead = curbuf->b_u_curhead;
+ #ifdef U_DEBUG
+ u_check(FALSE);
+ #endif
old_flags = curhead->uh_flags;
new_flags = (curbuf->b_changed ? UH_CHANGED : 0) +
((curbuf->b_ml.ml_flags & ML_EMPTY) ? UH_EMPTYBUF : 0);
***************
*** 1186,1191 ****
--- 1302,1310 ----
/* The timestamp can be the same for multiple changes, just use the one of
* the undone/redone change. */
curbuf->b_u_seq_time = curhead->uh_time;
+ #ifdef U_DEBUG
+ u_check(FALSE);
+ #endif
}
/*
***************
*** 1515,1521 ****
}
/*
! * Free one header and its entry list and adjust the pointers.
*/
static void
u_freeheader(buf, uhp, uhpp)
--- 1634,1640 ----
}
/*
! * Free one header "uhp" and its entry list and adjust the pointers.
*/
static void
u_freeheader(buf, uhp, uhpp)
***************
*** 1523,1528 ****
--- 1642,1649 ----
u_header_T *uhp;
u_header_T **uhpp; /* if not NULL reset when freeing this header */
{
+ u_header_T *uhap;
+
/* When there is an alternate redo list free that branch completely,
* because we can never go there. */
if (uhp->uh_alt_next != NULL)
***************
*** 1540,1546 ****
if (uhp->uh_prev == NULL)
buf->b_u_newhead = uhp->uh_next;
else
! uhp->uh_prev->uh_next = uhp->uh_next;
u_freeentries(buf, uhp, uhpp);
}
--- 1661,1668 ----
if (uhp->uh_prev == NULL)
buf->b_u_newhead = uhp->uh_next;
else
! for (uhap = uhp->uh_prev; uhap != NULL; uhap = uhap->uh_alt_next)
! uhap->uh_next = uhp->uh_next;
u_freeentries(buf, uhp, uhpp);
}
***************
*** 1585,1590 ****
--- 1707,1714 ----
/* Check for pointers to the header that become invalid now. */
if (buf->b_u_curhead == uhp)
buf->b_u_curhead = NULL;
+ if (buf->b_u_newhead == uhp)
+ buf->b_u_newhead = NULL; /* freeing the newest entry */
if (uhpp != NULL && uhp == *uhpp)
*uhpp = NULL;
***************
*** 1594,1599 ****
--- 1718,1726 ----
u_freeentry(uep, uep->ue_size);
}
+ #ifdef U_DEBUG
+ uhp->uh_magic = 0;
+ #endif
U_FREE_LINE((char_u *)uhp);
--buf->b_u_numhead;
}
***************
*** 1609,1614 ****
--- 1736,1744 ----
while (n > 0)
U_FREE_LINE(uep->ue_array[--n]);
U_FREE_LINE((char_u *)uep->ue_array);
+ #ifdef U_DEBUG
+ uep->ue_magic = 0;
+ #endif
U_FREE_LINE((char_u *)uep);
}
*** ../vim-7.1.129/src/structs.h Sun Aug 12 15:50:26 2007
--- src/structs.h Sat Sep 29 15:03:38 2007
***************
*** 278,283 ****
--- 278,286 ----
linenr_T ue_lcount; /* linecount when u_save called */
char_u **ue_array; /* array of lines in undo block */
long ue_size; /* number of lines in ue_array */
+ #ifdef U_DEBUG
+ int ue_magic; /* magic number to check allocation */
+ #endif
};
struct u_header
***************
*** 300,305 ****
--- 303,311 ----
visualinfo_T uh_visual; /* Visual areas before undo/after redo */
#endif
time_t uh_time; /* timestamp when the change was made */
+ #ifdef U_DEBUG
+ int uh_magic; /* magic number to check allocation */
+ #endif
};
/* values for uh_flags */
*** ../vim-7.1.129/src/version.c Mon Oct 1 20:33:45 2007
--- src/version.c Mon Oct 1 22:50:23 2007
***************
*** 668,669 ****
--- 668,671 ----
{ /* Add new patch number below this line */
+ /**/
+ 130,
/**/
--
FIRST SOLDIER: So they wouldn't be able to bring a coconut back anyway.
SECOND SOLDIER: Wait a minute! Suppose two swallows carried it together?
FIRST SOLDIER: No, they'd have to have it on a line.
"Monty Python and the Holy Grail" PYTHON (MONTY) PICTURES LTD
/// Bram Moolenaar -- Bram@Moolenaar.net -- http://www.Moolenaar.net \\\
/// sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ \\\
\\\ download, build and distribute -- http://www.A-A-P.org ///
\\\ help me help AIDS victims -- http://ICCF-Holland.org ///