patch 8.0.0551: the typeahead buffer is reallocated too often
Problem: The typeahead buffer is reallocated too often.
Solution: Re-use the existing buffer if possible.
diff --git a/src/getchar.c b/src/getchar.c
index c057861..18af2a3 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -920,7 +920,7 @@
typebuf.tb_noremap = noremapbuf_init;
typebuf.tb_buflen = TYPELEN_INIT;
typebuf.tb_len = 0;
- typebuf.tb_off = 0;
+ typebuf.tb_off = MAXMAPLEN + 4;
typebuf.tb_change_cnt = 1;
}
}
@@ -974,11 +974,21 @@
typebuf.tb_off -= addlen;
mch_memmove(typebuf.tb_buf + typebuf.tb_off, str, (size_t)addlen);
}
+ else if (typebuf.tb_len == 0 && typebuf.tb_buflen
+ >= addlen + 3 * (MAXMAPLEN + 4))
+ {
+ /*
+ * Buffer is empty and string fits in the existing buffer.
+ * Leave some space before and after, if possible.
+ */
+ typebuf.tb_off = (typebuf.tb_buflen - addlen - 3 * (MAXMAPLEN + 4)) / 2;
+ mch_memmove(typebuf.tb_buf + typebuf.tb_off, str, (size_t)addlen);
+ }
else
{
/*
* Need to allocate a new buffer.
- * In typebuf.tb_buf there must always be room for 3 * MAXMAPLEN + 4
+ * In typebuf.tb_buf there must always be room for 3 * (MAXMAPLEN + 4)
* characters. We add some extra room to avoid having to allocate too
* often.
*/
@@ -1291,7 +1301,7 @@
return FAIL;
}
typebuf.tb_buflen = TYPELEN_INIT;
- typebuf.tb_off = 0;
+ typebuf.tb_off = MAXMAPLEN + 4; /* can insert without realloc */
typebuf.tb_len = 0;
typebuf.tb_maplen = 0;
typebuf.tb_silent = 0;