1 files changed, 44 insertions, 0 deletions
diff --git a/lib/crypto-algorithms/rot-13_test.c b/lib/crypto-algorithms/rot-13_test.c
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+++ b/lib/crypto-algorithms/rot-13_test.c
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+/*********************************************************************
+* Filename:   rot-13_test.c
+* Author:     Brad Conte (brad AT bradconte.com)
+* Copyright:
+* Disclaimer: This code is presented "as is" without any guarantees.
+* Details:    Performs known-answer tests on the corresponding ROT-13
+	          implementation. These tests do not encompass the full
+	          range of available test vectors, however, if the tests
+	          pass it is very, very likely that the code is correct
+	          and was compiled properly. This code also serves as
+	          example usage of the functions.
+*********************************************************************/
+
+/*************************** HEADER FILES ***************************/
+#include <stdio.h>
+#include <string.h>
+#include "rot-13.h"
+
+/*********************** FUNCTION DEFINITIONS ***********************/
+int rot13_test()
+{
+	char text[] = {"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"};
+	char code[] = {"NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm"};
+	char buf[1024];
+	int pass = 1;
+
+	// To encode, just apply ROT-13.
+	strcpy(buf, text);
+	rot13(buf);
+	pass = pass && !strcmp(code, buf);
+
+	// To decode, just re-apply ROT-13.
+	rot13(buf);
+	pass = pass && !strcmp(text, buf);
+
+	return(pass);
+}
+
+int main()
+{
+	printf("ROT-13 tests: %s\n", rot13_test() ? "SUCCEEDED" : "FAILED");
+
+	return(0);
+}