c指针应用：键值对"key=value"字符串，在开发中经常使用

/*要求写一个函数实现如下功能

要求1：自己定义一个接口，实现根据key获取value

要求2：编写测试用例

要求3：键值对中间可能有多个空格，请清除空格

键值对可能如下

“key1= buf1 “;

“key2= buf2 “;

“key3= buf3 “;

“key4= buf4 “;

“key5= buf5 “;

*/

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

int trimspace(char *str, char *newstr)//除去buff前后空格
{
char *phead = str;
int i = 0;
int j = strlen(phead) - 1;
if (phead == NULL || newstr == NULL)
{
return -1;
}
while (isspace(phead[i])&& phead[i] != '\0')
{
i++;
}
while (isspace(phead[j]) && phead[j] != '\0')
{
j--;
}
int count = j - i + 1;
strncpy(newstr, phead + i, count);
newstr[count] = '\0';
return 1;
}

int getbuff(char *keybuff, char *key, char *buf)
{
char *p = keybuff;//指针初始化
//判断是否存在key
p = strstr(p, key);
if (p == NULL)
{
printf("There is no %s", key);
return -1;
}
//判断等号是否存在
p = strstr(p, "=");
if (p == NULL)
{
printf("There is no buff for %s", key);
return -1;
}
//除去key对应字符子串的前后空格
p = keybuff+ strlen(key) + strlen("=");
int ret=trimspace(p, buf);
if (ret != 1)
{
printf("delete sapace fail");
return -1;
}
return 1;
}
void main()
{
char *str[] = { "key1=  buf1     " ,"key2=   buf2    ", "key3=    buf3   ",
"key4=     buf4  " ,"key5=      buf5 " };
//  char *keybuf = "key2=   buf2    ";
//  char *key = "key2";
char key[5];
char buf[50] = { 0 };
int ret,i;

printf("Please input key(key1~key5:");
scanf("%s", key);
//  for (i = 0; i < 5; i++)
switch (key[3])
{
case '1':i = 0; break;
case '2':i = 1; break;
case '3':i = 2; break;
case '4':i = 3; break;
case '5':i = 4; break;
}
//ret = getbuff(keybuf, key, buf);
ret = getbuff(str[i], key, buf);

if (ret != 1)
{
printf("funtion getbuff err\n");
}
else
{
printf("%s:%s\n", key, buf);

}
}