From f089257d7b573dcff409a5fb0b140fa5c6e4ca84 Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Sat, 1 Nov 2014 14:04:17 +0100 Subject: shared: add helpers for unaligend BE read/write --- src/shared/unaligned.h | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 src/shared/unaligned.h (limited to 'src/shared/unaligned.h') diff --git a/src/shared/unaligned.h b/src/shared/unaligned.h new file mode 100644 index 0000000000..b194d71017 --- /dev/null +++ b/src/shared/unaligned.h @@ -0,0 +1,56 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +#pragma once + +/*** + This file is part of systemd. + + Copyright 2014 Tom Gundersen + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include + +#include "sparse-endian.h" + +static inline uint16_t unaligned_read_be16(const be16_t *u) { + return (((uint16_t) ((uint8_t*) u)[0]) << 8) | + ((uint16_t) ((uint8_t*) u)[1]); +} + +static inline uint32_t unaligned_read_be32(const be32_t *u) { + return (((uint32_t) unaligned_read_be16((be16_t*) u)) << 16) | + ((uint32_t) unaligned_read_be16((be16_t*) u + 1)); +} + +static inline uint64_t unaligned_read_be64(const be64_t *u) { + return (((uint64_t) unaligned_read_be32((be32_t*) u)) << 32) | + ((uint64_t) unaligned_read_be32((be32_t*) u + 1)); +} + +static inline void unaligned_write_be16(be16_t *u, uint16_t a) { + ((uint8_t*) u)[0] = (uint8_t) (a >> 8); + ((uint8_t*) u)[1] = (uint8_t) a; +} + +static inline void unaligned_write_be32(be32_t *u, uint32_t a) { + unaligned_write_be16((be16_t*) u, (uint16_t) (a >> 16)); + unaligned_write_be16((be16_t*) u + 1, (uint16_t) a); +} + +static inline void unaligned_write_be64(be64_t *u, uint64_t a) { + unaligned_write_be32((be32_t*) u, (uint32_t) (a >> 32)); + unaligned_write_be32((be32_t*) u + 1, (uint32_t) a); +} -- cgit v1.2.3-54-g00ecf