大小端测试, 原来openwrt是大端存储模式(WR703N下测试)

1. 测试代码

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int agrc, char *argv[])
{
    printf("short = %d, int = %d, long = %d\n", sizeof(short), sizeof(int), sizeof(long));

    unsigned short test = 0x1234;
    //unsigned long test = 0x12345678;
    if(*( (unsigned char*) &test ) == 0x12)
        printf("1: Big Endian\n");
    else
        printf("1: Little Endian\n");

    static union {
     char c[4];
     unsigned int tmp;
    } endian_test = { { 'l','?','?','b' } };
    unsigned char uctmp = (char)endian_test.tmp;

    if (uctmp == 'b') {
        printf("2: Big Endian\n");
    }
    else if(uctmp == 'l') {
        printf("2: Little Endian\n");
    }

    static union {
     char c[4];
     unsigned int tmp;
    } endian_test1 = {0x12, 0x34, 0x56, 0x78};

    printf("endian_test.tmp = 0x%08X\n", endian_test1.tmp);
    printf("(char)endian_test.tmp = 0x%02X\n", (char)endian_test1.tmp);
    if (endian_test1.tmp == 0x12345678) {
        printf("3: Big Endian\n");
    }
    else if(endian_test1.tmp == 0x78563412) {
        printf("3: Little Endian\n");
    }

    return 1;

}

2. 运行结果
虚拟机运行结果如下:
xxg@xxg-desktop:~/1-wire/hmac_sha1$ ./hello
short = 2, int = 4, long = 4
1: Little Endian
2: Little Endian
endian_test.tmp = 0x78563412
(char)endian_test.tmp = 0x12
3: Little Endian


openwrt下运行结果如下:
root@OpenWrt:/xutest# ./hello
short = 2, int = 4, long = 4
1: Big Endian
2: Big Endian
endian_test.tmp = 0x12345678
(char)endian_test.tmp = 0x78
3: Big Endian