Improve register_hash()

Only go once through `hash_descriptor[]` when calling `register_hash()`

Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>

Author: sjaeckel

src/misc/crypt/crypt_register_hash.c

@@ -14,26 +14,30 @@
 */
 int register_hash(const struct ltc_hash_descriptor *hash)
 {
-   int x;
+   int x, blank = -1;
 
    LTC_ARGCHK(hash != NULL);
 
+   if (hash->name == NULL)
+      return -1;
+
    /* is it already registered? */
    LTC_MUTEX_LOCK(&ltc_hash_mutex);
    for (x = 0; x < TAB_SIZE; x++) {
        if (XMEMCMP(&hash_descriptor[x], hash, sizeof(struct ltc_hash_descriptor)) == 0) {
           LTC_MUTEX_UNLOCK(&ltc_hash_mutex);
           return x;
        }
+       if (hash_descriptor[x].name == NULL && blank == -1) {
+          blank = x;
+       }
    }
 
-   /* find a blank spot */
-   for (x = 0; x < TAB_SIZE; x++) {
-       if (hash_descriptor[x].name == NULL) {
-          XMEMCPY(&hash_descriptor[x], hash, sizeof(struct ltc_hash_descriptor));
-          LTC_MUTEX_UNLOCK(&ltc_hash_mutex);
-          return x;
-       }
+   /* fill in blank spot */
+   if (blank != -1) {
+       XMEMCPY(&hash_descriptor[blank], hash, sizeof(struct ltc_hash_descriptor));
+       LTC_MUTEX_UNLOCK(&ltc_hash_mutex);
+       return x;
    }
 
    /* no spot */