#include <stdio.h> #include <stdio.h>
typedef unsigned int u32; typedef unsigned short u16;
#if 0 //simple: not check varible types
#define BSWAP_16(x) \ ( (((x) & 0x00ff) << 8 ) | \ (((x) & 0xff00) >> 8 ) \ )
//complex:check varible types
#else #define BSWAP_16(x) \ (u16) ( ((((u16)(x)) & 0x00ff) << 8 ) | \ ((((u16)(x)) & 0xff00) >> 8 ) \ )
#endif #define BSWAP_32(x) \ (u32) ( (( ((u32)(x)) & 0xff000000 ) >> 24) | \ (( ((u32)(x)) & 0x00ff0000 ) >> 8 ) | \ (( ((u32)(x)) & 0x0000ff00 ) << 8 ) | \ (( ((u32)(x)) & 0x000000ff ) << 24) \ )
u16 bswap16(u16 x) { return (x & 0x00ff) << 8 | (x & 0xff00) >> 8 ; }
u32 bswap32(u32 x) { return ( x & 0xff000000 ) >>24 | ( x & 0x00ff0000 ) >>8 | ( x & 0x0000ff00 ) <<8 | ( x & 0x000000ff ) << 24 ; }
int main(void) { //u16 var_short = 0x123490;
//u32 var_int = 0x1234567890;
//关键是要能对错误进行处理,给一个0x123490 照样能得出 0x9034的值,而且, 占内存要小的
printf("macro conversion:%#x\n",BSWAP_16(0x123490 ));//要能正确转换
printf("macro conversion:%#x\n", BSWAP_32(0x1234567890)); //要能正确转换
printf("-----------------\n"); printf("function conversion:%#x\n",bswap16(0x123490)); printf("function conversion:%#x\n", bswap32(0x1234567890)); return 0; }
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