The generic swap() is not able to swap a NonnullRefPtr with itself,
due to its use of a temporary and NonnullRefPtr asserting when trying
to move() from an already move()'d instance.
Given the following situation:
struct Object : public RefCounted<Object> {
RefPtr<Object> parent;
}
NonnullRefPtr<Object> object = get_some_object();
object = *object->parent;
We would previously crash if 'object' was the only strongly referencing
pointer to 'parent'. This happened because NonnullRefPtr would unref
the outgoing pointee before reffing the incoming pointee.
This patch fixes that by implementing NonnullRefPtr assignments using
pointer swaps, just like RefPtr already did.
As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.
Let's just not support building that way, so String.h can have an
objectively nicer name. :^)