Clarify that lj_buf_shrink() does not keep any buffer data.

https://www.freelists.org/post/luajit/lj-buf-shrink-may-truncate-the-data-and-sbw-point-over-the-end-of-the-buffer,1
Thanks to Junlong li.
This commit is contained in:
Mike Pall 2024-07-04 00:03:40 +02:00
parent 747fc02eb9
commit 444c8ff19a

View File

@ -92,10 +92,8 @@ void LJ_FASTCALL lj_buf_shrink(lua_State *L, SBuf *sb)
char *b = sb->b;
MSize osz = (MSize)(sb->e - b);
if (osz > 2*LJ_MIN_SBUF) {
MSize n = (MSize)(sb->w - b);
b = lj_mem_realloc(L, b, osz, (osz >> 1));
sb->b = b;
sb->w = b + n;
sb->w = sb->b = b; /* Not supposed to keep data across shrinks. */
sb->e = b + (osz >> 1);
}
lj_assertG_(G(sbufL(sb)), !sbufisext(sb), "YAGNI shrink SBufExt");