diff options
author | David Monniaux <david.monniaux@univ-grenoble-alpes.fr> | 2020-03-03 08:17:40 +0100 |
---|---|---|
committer | David Monniaux <david.monniaux@univ-grenoble-alpes.fr> | 2020-03-03 08:17:40 +0100 |
commit | 1ab7b51c30e1b10ac45b0bd64cefdc01da0f7f68 (patch) | |
tree | 210ffc156c83f04fb0c61a40b4f9037d7ba8a7e1 /test/monniaux/crypto-algorithms/rot-13.c | |
parent | 222c9047d61961db9c6b19fed5ca49829223fd33 (diff) | |
parent | 12be46d59a2483a10d77fa8ee67f7e0ca1bd702f (diff) | |
download | compcert-kvx-1ab7b51c30e1b10ac45b0bd64cefdc01da0f7f68.tar.gz compcert-kvx-1ab7b51c30e1b10ac45b0bd64cefdc01da0f7f68.zip |
Merge branch 'mppa-cse2' of gricad-gitlab.univ-grenoble-alpes.fr:sixcy/CompCert into mppa-work
Diffstat (limited to 'test/monniaux/crypto-algorithms/rot-13.c')
-rw-r--r-- | test/monniaux/crypto-algorithms/rot-13.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/test/monniaux/crypto-algorithms/rot-13.c b/test/monniaux/crypto-algorithms/rot-13.c new file mode 100644 index 00000000..0ab84975 --- /dev/null +++ b/test/monniaux/crypto-algorithms/rot-13.c @@ -0,0 +1,35 @@ +/********************************************************************* +* Filename: rot-13.c +* Author: Brad Conte (brad AT bradconte.com) +* Copyright: +* Disclaimer: This code is presented "as is" without any guarantees. +* Details: Implementation of the ROT-13 encryption algorithm. + Algorithm specification can be found here: + * + This implementation uses little endian byte order. +*********************************************************************/ + +/*************************** HEADER FILES ***************************/ +#include <string.h> +#include "rot-13.h" + +/*********************** FUNCTION DEFINITIONS ***********************/ +void rot13(char str[]) +{ + int case_type, idx, len; + + for (idx = 0, len = strlen(str); idx < len; idx++) { + // Only process alphabetic characters. + if (str[idx] < 'A' || (str[idx] > 'Z' && str[idx] < 'a') || str[idx] > 'z') + continue; + // Determine if the char is upper or lower case. + if (str[idx] >= 'a') + case_type = 'a'; + else + case_type = 'A'; + // Rotate the char's value, ensuring it doesn't accidentally "fall off" the end. + str[idx] = (str[idx] + 13) % (case_type + 26); + if (str[idx] < 26) + str[idx] += case_type; + } +} |