src: piece-table: optimize when adding to a piece in the end of the bufferHEADmaster

1 files changed, 14 insertions, 0 deletions

diff --git a/src/piece-table.c b/src/piece-table.c
index a41cf00..d77ffa0 100644
--- a/src/piece-table.c
+++ b/src/piece-table.c
@@ -153,6 +153,8 @@ void insert_piece_table(piece_table *pt, size_t pos, char *in, size_t in_len) {
         start = pt->sentinel;
     } else if ( pos == pt->length ) {
         start = pt->sentinel->prev;
+        pt->cached_offset = pt->length - start->length;
+        pt->cached = start;
     } else {
         find_piece_by_pos(pt, pos);
         start = split_piece(pt->cached, pos - pt->cached_offset);
@@ -168,6 +170,18 @@ void insert_piece_table(piece_table *pt, size_t pos, char *in, size_t in_len) {
         pt->cached_offset -= pt->cached->length;
     }
 
+    /* Optimization!
+     * Add in the end of the buffer, and the end of the piece: enlarge
+     */
+    if ( pt->add.used != 0 &&
+         pt->cached_offset + start->length == pos &&
+         pt->add.content + pt->add.used ==
+            start->start + start->length + in_len ) {
+        pt->length += in_len;
+        start->length += in_len;
+        return;
+    }
+    /* Make a new piece and insert it */
     new = make_piece();
     new->start = pt->add.content + pt->add.used - in_len;
     new->length = in_len;