fix revision management for edit buffers

Two bugs are now gone.  When undoing, the current revision
number was not properly reset to the previous one.  Revisions
corresponding to new modifications need new numbers, so we
keep a static variable 'grev' to generate fresh revision
numbers.

1 files changed, 6 insertions, 2 deletions

diff --git a/edit.c b/edit.c
index c5a19dd..8376e35 100644
--- a/edit.c
+++ b/edit.c
@@ -90,8 +90,10 @@ log_revision(Log *l)
 void
 log_commit(Log *l, unsigned rev)
 {
+	static unsigned grev = 1;
+
 	if (!rev)
-		rev = log_revision(l) + 1;
+		rev = ++grev;
 	pushlog(l, Commit);
 	l->p0 = rev;
 }
@@ -139,10 +141,12 @@ log_undo(Log *l, Buf *b, Log *redo, unsigned *pp)
 		l = n;
 	}
 
+	p0 = top->p0;
+	top->p0 = l->p0;
 	top->next = l->next;
 	free(l);
 	if (redo)
-		log_commit(redo, top->p0);
+		log_commit(redo, p0);
 }
 
 Log *