xnu-7195.81.3.tar.gz

[apple/xnu.git] / libsyscall / wrappers / skywalk / cpu_copy_in_cksum.s

/*
 * Copyright (c) 2017 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
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 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
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 * The Original Code and all software distributed under the License are
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/*
 *  extern int cpu_copy_in_cksum(const void *src, void *dst, uint32_t len,
 *	uint32_t initial_sum);
 *
 *  input :
 *      src : source starting address
 *      dst : destination starting address
 *      len : byte stream length
 *      initial_sum : 32bit sum
 *
 *  output :
 *      the source byte stream is copied into the destination buffer
 *      the function returns the final 16bit checksum
 */