#include <mango/status.h>
#include <xpc/buffer.h>
#include <xpc/msg.h>

kern_status_t xpc_buffer_read(
	const xpc_buffer_t *buf,
	void *out,
	size_t max,
	size_t *nr_read)
{
	if ((buf->buf_flags & (XPC_BUFFER_F_IN | XPC_BUFFER_F_REMOTE))
	    != (XPC_BUFFER_F_IN | XPC_BUFFER_F_REMOTE)) {
		return KERN_BAD_STATE;
	}

	size_t to_read = max;
	if (to_read > buf->buf_len) {
		to_read = buf->buf_len;
	}

	kern_status_t status
		= xpc_msg_read(buf->buf_origin, buf->buf_offset, out, to_read);
	if (status != KERN_OK) {
		return status;
	}

	/* TODO */
	*nr_read = to_read;

	return KERN_OK;
}

kern_status_t xpc_buffer_write(
	xpc_buffer_t *buf,
	const void *in,
	size_t len,
	size_t *nr_written)
{
	if ((buf->buf_flags & (XPC_BUFFER_F_OUT | XPC_BUFFER_F_REMOTE))
	    != (XPC_BUFFER_F_OUT | XPC_BUFFER_F_REMOTE)) {
		return KERN_BAD_STATE;
	}

	size_t to_write = len;
	if (to_write > buf->buf_max) {
		to_write = buf->buf_max;
	}

	kern_status_t status
		= xpc_msg_write(buf->buf_origin, buf->buf_offset, in, to_write);
	if (status != KERN_OK) {
		return status;
	}

	/* TODO */
	*nr_written = to_write;

	return KERN_OK;
}