test: add test case for performance

test/utils.cc

@@ -0,0 +1,58 @@
+#include "include/utils.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+namespace smartdns
+{
+
+bool IsCommandExists(const std::string &cmd)
+{
+	char *copy_path = NULL;
+	char cmd_path[4096];
+	const char *env_path = getenv("PATH");
+	char *save_ptr = NULL;
+
+	if (env_path == NULL) {
+		env_path = "/bin:/usr/bin:/usr/local/bin";
+	}
+
+	copy_path = strdup(env_path);
+	if (copy_path == NULL) {
+		return false;
+	}
+
+	Defer
+	{
+		free(copy_path);
+	};
+
+	for (char *tok = strtok_r(copy_path, ":", &save_ptr); tok; tok = strtok_r(NULL, ":", &save_ptr)) {
+		snprintf(cmd_path, sizeof(cmd_path), "%s/%s", tok, cmd.c_str());
+		if (access(cmd_path, X_OK) != 0) {
+			continue;
+		}
+
+		return true;
+	}
+
+	return false;
+}
+
+std::string GenerateRandomString(int len)
+{
+    std::string result;
+	static const char alphanum[] = "0123456789"
+								   "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+								   "abcdefghijklmnopqrstuvwxyz";
+    result.resize(len);
+
+    for (int i = 0; i < len; ++i) {
+        result[i] = alphanum[rand() % (sizeof(alphanum) - 1)];
+    }
+
+    return result;
+}
+
+} // namespace smartdns