basename.cc

#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>

#include <libgen.h>

using namespace std;

char* my_basename(char* str) {
	static char* buf = NULL;
	static size_t buf_len = 0;

	size_t len = strlen(str);
	if (len == 0) {
		if (buf_len < 2) {
			buf = (char*)::realloc(buf, 2);
			buf_len = 2;
			::strncpy(buf, ".", 2);
		}
		return buf;
	}

	if (str[len-1] == '/') {
		len--;
	}

	while (len > 0) {
		if (str[len-1] == '/') break;
		len--;
	}

	return str + len ;
}

void test(const char* str, bool verbose=false) {
	size_t len = strlen(str);
	char* str2 = new char[len + 1];
	strncpy(str2, str, len + 1);
	std::string input = str;
	std::string ref = ::basename(str2);
	std::string ans = ::my_basename(str2);
	if (ref == ans) {
		std::cout << "ok\t" << input << std::endl;
	} else {
		std::cout << "Bad answer on \"" << input << "\"" << std::endl;
		std::cout << "Expected : " << ref << std::endl;
		std::cout << "Actual   : " << ans << std::endl;
		std::cout << "-----------" << std::endl;
	}
	delete[] str2;
}

int main() {
	test("/foo/bar");
	test("/foo/bar/");
	test("/");
	test("test");
	test("");
	test("..");
	test("/..");
	test("/../");
	test("/./.");
	test("/././");
	test("./");
	test("//");
	test("//..");
}