These accessors will not allocate, and are mainly here to assist in building low-cost syscall wrappers.

One must be careful to avoid writing out of the limits (between lo_min and hi_max) of the buf. Doing so would violate the invariants of the parent Iobuf.

These setters directly set fields in t without checking any invariants.

to_bigstring_shared t and to_iobuf_shared t allocate new wrappers around the storage of buf t, relative to t's current bounds.

These operations allow access outside the bounds and limits of t, and without respect to its read/write access. Be careful not to violate t's invariants.

reinitialize_of_bigstring t bigstring reinitializes t with backing bigstring, and the window and limits specified starting at pos and of length len.

As reinitialize_of_bigstring but without checking, and requires explicit specification of bounds.

These versions of set_bounds_and_buffer allow ~src to be read-only. ~dst will be writable through ~src aliases even though the type does not reflect this!

Similar to protect_window_bounds_and_buffer, but does not save/restore the buffer or bounds. Mixing this with functions like set_bounds_and_buffer or narrow is unsafe; you should not modify anyything but the window inside f.

Computes the position within buf for pos relative to our window. Checks len bytes are available.

As buf_pos_exn without checks.