优化查询IP地址

common.c

@@ -143,3 +143,29 @@ char *_time()
     return strdup(temp);
 }
 
+int is_valid_ip(const char *ip)
+{
+    struct sockaddr_in sa;
+    // 尝试将字符串转换为IPv4地址
+    int result = inet_pton(AF_INET, ip, &(sa.sin_addr));
+
+    return result != 0;
+}
+
+int nice_(int increment)
+{
+    int oldprio = getpriority(PRIO_PROCESS, getpid());
+    printf("%d\n", oldprio);
+
+    return setpriority(PRIO_PROCESS, getpid(), oldprio + increment);
+}
+
+// 判断命令是否存在
+int command_exists(const char *command)
+{
+    char buffer[BUFFER];
+    snprintf(buffer, sizeof(buffer), "%s > /dev/null 2>&1", command);
+    int status = system(buffer);
+
+    return (status == 0);
+}