1、C语言宏定义技巧（常用宏定义） 写好C语言，漂亮的宏定义很重要，使用宏定义可以防止出错，提高可移植性，可读性，方便性 等等。下面列举一些成熟软件中常用得宏定义。。。。。。 1，防止一个头文件被重复包含#ifndef COMDEF_H#define COMDEF_H //头文件内容#endif2，重新定义一些类型，防止由于各种平台和编译器的不同，而产生的类型字节数差异，方便移植。typedef unsigned char boolean; /* Boolean value type. */ typedef unsigned long i
2、nt uint32; /* Unsigned 32 bit value */typedef unsigned short uint16; /* Unsigned 16 bit value */typedef unsigned char uint8; /* Unsigned 8 bit value */ typedef signed long int int32; /* Signed 32 bit value */typedef signed short int16;
3、 /* Signed 16 bit value */typedef signed char int8; /* Signed 8 bit value */ //下面的不建议使用typedef unsigned char byte; /* Unsigned 8 bit value type. */typedef unsigned short word; /* Unsinged 16 bit value type. */typedef unsigned long
4、dword; /* Unsigned 32 bit value type. */ typedef unsigned char uint1; /* Unsigned 8 bit value type. */typedef unsigned short uint2; /* Unsigned 16 bit value type. */typedef unsigned long uint4; /* Unsigned 32 bit value type. */ typedef sig
5、ned char int1; /* Signed 8 bit value type. */typedef signed short int2; /* Signed 16 bit value type. */typedef long int int4; /* Signed 32 bit value type. */ typedef signed long sint31; /* Signed 32 bit value */typedef sig
6、ned short sint15; /* Signed 16 bit value */typedef signed char sint7; /* Signed 8 bit value */ 3，得到指定地址上的一个字节或字#define MEM_B( x ) ( *( (byte *) (x) ) )#define MEM_W( x ) ( *( (word *) (x) ) )4，求最大值和最小值 #define MAX( x, y ) ( ((x) > (y)) ? (x) : (y) )
7、 #define MIN( x, y ) ( ((x) < (y)) ? (x) : (y) )5，得到一个field在结构体(struct)中的偏移量#define FPOS( type, field ) /*lint -e545 */ ( (dword) &(( type *) 0)-> field ) /*lint +e545 */6,得到一个结构体中field所占用的字节数#define FSIZ( type, field ) sizeof( ((type *) 0)->field )7，按照LSB格式把两个字节转化为一个Word#define
