Re: [GSOC] [QUESTION] ref-filter: can %(raw) implement reuse oi.content?

ZheNing Hu [off-list ref] 于2021年8月18日周三 下午5:07写道：

quoted

I think the 'buf' is not freed in ref-filter logic.

But one thing worth noting is:

parse_object_buffer() may take this buffer away, and store it in
tree->buffer or use set_commit_buffer() to store it in commit_slab.

So in theory, as long as we don’t use parse_object_buffer(), this
dynamically allocated memory can be used freely for us. If we use
parse_object_buffer() and free the buffer, there seems to be a risk,
but it does not appear so far.

When parse_object_buffer() hints that we don’t free the buffer when
eaten == 1, I have a better idea, If the buffer is "eaten", we copy it,
otherwise we use the originally allocated space.

-static void grab_sub_body_contents(struct atom_value *val, int deref,
struct expand_data *data)
+static void grab_sub_body_contents(struct atom_value *val, int deref,
struct expand_data *data, int eaten)
 {
        int i;
        const char *subpos = NULL, *bodypos = NULL, *sigpos = NULL;

@@ -1499,7 +1499,10 @@ static void grab_sub_body_contents(struct

atom_value *val, int deref, struct exp
                        unsigned long buf_size = data->size;

                        if (atom->u.raw_data.option == RAW_BARE) {
-                               v->s = buf;
+                               if (eaten)
+                                       v->s = xmemdupz(buf, buf_size);