image/src/EndianMacros.h
author Ed Morley <emorley@mozilla.com>
Tue, 30 Oct 2012 17:02:31 +0000
changeset 120431 ad1d720d82b7f84d3c7e50f4b02b7c3201662ddb
parent 114251 7d41b1e032716ec8da9cc5afa61c4ce8b2414d1f
child 123540 1326ff4b33980720a09e785ceb1ceb208b77a77f
permissions -rw-r--r--
Backout a145ded68994, e0cf397089ec & 1545e91c658e (bug 798491) for bustage on a CLOSED TREE

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef MOZILLA_IMAGELIB_ENDIAN_H_
#define MOZILLA_IMAGELIB_ENDIAN_H_


#if defined WORDS_BIGENDIAN || defined IS_BIG_ENDIAN
// We must ensure that the entity is unsigned
// otherwise, if it is signed/negative, the MSB will be
// propagated when we shift
#define LITTLE_TO_NATIVE16(x) (((((uint16_t) x) & 0xFF) << 8) | \
                               (((uint16_t) x) >> 8))
#define LITTLE_TO_NATIVE32(x) (((((uint32_t) x) & 0xFF) << 24) | \
                               (((((uint32_t) x) >> 8) & 0xFF) << 16) | \
                               (((((uint32_t) x) >> 16) & 0xFF) << 8) | \
                               (((uint32_t) x) >> 24))
#define NATIVE32_TO_LITTLE LITTLE_TO_NATIVE32
#define NATIVE16_TO_LITTLE LITTLE_TO_NATIVE16
#else
#define LITTLE_TO_NATIVE16(x) x
#define LITTLE_TO_NATIVE32(x) x
#define NATIVE32_TO_LITTLE(x) x
#define NATIVE16_TO_LITTLE(x) x
#endif

#endif