1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 // 18 19 #ifndef _LIBS_UTILS_BYTE_ORDER_H 20 #define _LIBS_UTILS_BYTE_ORDER_H 21 22 #include <stdint.h> 23 #include <sys/types.h> 24 #if defined(_WIN32) 25 #include <winsock2.h> 26 #else 27 #include <netinet/in.h> 28 #endif 29 30 /* 31 * These macros are like the hton/ntoh byte swapping macros, 32 * except they allow you to swap to and from the "device" byte 33 * order. The device byte order is the endianness of the target 34 * device -- for the ARM CPUs we use today, this is little endian. 35 * 36 * Note that the byte swapping functions have not been optimized 37 * much; performance is currently not an issue for them since the 38 * intent is to allow us to avoid byte swapping on the device. 39 */ 40 41 static inline uint32_t android_swap_long(uint32_t v) 42 { 43 return (v<<24) | ((v<<8)&0x00FF0000) | ((v>>8)&0x0000FF00) | (v>>24); 44 } 45 46 static inline uint16_t android_swap_short(uint16_t v) 47 { 48 return (v<<8) | (v>>8); 49 } 50 51 #define DEVICE_BYTE_ORDER LITTLE_ENDIAN 52 53 #if BYTE_ORDER == DEVICE_BYTE_ORDER 54 55 #define dtohl(x) (x) 56 #define dtohs(x) (x) 57 #define htodl(x) (x) 58 #define htods(x) (x) 59 60 #else 61 62 #define dtohl(x) (android_swap_long(x)) 63 #define dtohs(x) (android_swap_short(x)) 64 #define htodl(x) (android_swap_long(x)) 65 #define htods(x) (android_swap_short(x)) 66 67 #endif 68 69 #if BYTE_ORDER == LITTLE_ENDIAN 70 #define fromlel(x) (x) 71 #define fromles(x) (x) 72 #define tolel(x) (x) 73 #define toles(x) (x) 74 #else 75 #define fromlel(x) (android_swap_long(x)) 76 #define fromles(x) (android_swap_short(x)) 77 #define tolel(x) (android_swap_long(x)) 78 #define toles(x) (android_swap_short(x)) 79 #endif 80 81 #endif // _LIBS_UTILS_BYTE_ORDER_H 82
