mem中需找特定字符

memstr

 //find 'substr' from a fixed-length buffer
 //('full_data' will be treated as binary data buffer)
 //return NULL if not found
 char* memstr(char* full_data, int full_data_len, char* substr)
 {
     if (full_data == NULL || full_data_len <=  || substr == NULL) {
         return NULL;
     }
 
     if (*substr == '\0') {
         return NULL;
     }
 
     int sublen = strlen(substr);
 
     int i;
     char* cur = full_data;
     int last_possible = full_data_len - sublen + ;
     for (i = ; i < last_possible; i++) {
         if (*cur == *substr) {
             //assert(full_data_len - i >= sublen);
             if (memcmp(cur, substr, sublen) == ) {
                 //found
                 return cur;
             }
         }
         cur++;
     }
 
     return NULL;
 }

memfind

 char* memstr(char* full_data, int full_data_len, char* substr, int substr_len)
 {
 
 }