/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, tomstdenis@iahu.ca, http://libtomcrypt.org */#include "mycrypt.h"int register_cipher(const struct _cipher_descriptor *cipher){   int x;   _ARGCHK(cipher != NULL);   /* is it already registered? */   for (x = 0; x < TAB_SIZE; x++) {       if (cipher_descriptor[x].name != NULL && cipher_descriptor[x].ID == cipher->ID) {          return x;       }   }   /* find a blank spot */   for (x = 0; x < TAB_SIZE; x++) {       if (cipher_descriptor[x].name == NULL) {          memcpy(&cipher_descriptor[x], cipher, sizeof(struct _cipher_descriptor));          return x;       }   }   /* no spot */   return -1;}