piece-table: split better

1 files changed, 10 insertions, 6 deletions

diff --git a/src/piece-table.c b/src/piece-table.c
index 5f2b171..e869ae2 100644
--- a/src/piece-table.c
+++ b/src/piece-table.c
@@ -119,17 +119,23 @@ char index_piece_table(piece_table *pt, size_t pos) {
 }
 
 
-static void split_piece(piece *p, size_t pos) {
+static piece *split_piece(piece *p, size_t pos) {
+    /* Returns the first piece */
+    piece *second;
     assert(pos < p->length);
     assert(p->start != NULL); /* Not a sentinel piece */
     assert(p->start != 0);    /* Not an empty piece (they should not exist) */
-    piece *second = make_piece();
+    if ( pos == 0 ) {
+        return p->prev;
+    }
+    second = make_piece();
     second->length = p->length - pos;
     p->length = pos;
     second->next = p->next;
     p->next = second;
     second->prev = p;
     second->start = p->start + pos;
+    return p;
 }
 
 void insert_piece_table(piece_table *pt, char val, size_t pos) {
@@ -149,16 +155,14 @@ void delete_piece_table(piece_table *pt, size_t pos, size_t len) {
         start = pt->sentinel;
     } else {
         find_piece_by_pos(pt, pos);
-        split_piece(pt->cached, pos - pt->cached_offset);
-        start = pt->cached;
+        start = split_piece(pt->cached, pos - pt->cached_offset);
     }
 
     if (pos + len == pt->length) {
         end = pt->sentinel;
     } else {
         find_piece_by_pos(pt, pos + len);
-        split_piece(pt->cached, pos + len - pt->cached_offset);
-        end = pt->cached->next;
+        end = split_piece(pt->cached, pos + len - pt->cached_offset)->next;
     }
 
     /* Free unneeded pieces */