print_hex() is always followed by putc('\n'), so let it do it directly

demos/auth.c

@@ -52,7 +52,6 @@ auth(void)
 
     fputs("Authentication tag: ", stdout);
     print_hex(mac, sizeof mac);
-    putchar('\n');
 
     puts("Verifying authentication tag...");
     ret = crypto_auth_verify(mac, message, message_len, key);

demos/box.c

@@ -72,31 +72,25 @@ box(void)
     puts("Bob");
     fputs("Public key: ", stdout);
     print_hex(bob_pk, sizeof bob_pk);
-    putchar('\n');
     fputs("Secret key: ", stdout);
     print_hex(bob_sk, sizeof bob_sk);
-    putchar('\n');
 
     puts("Alice");
     fputs("Public key: ", stdout);
     print_hex(alice_pk, sizeof alice_pk);
-    putchar('\n');
     fputs("Secret key: ", stdout);
     print_hex(alice_sk, sizeof alice_sk);
-    putchar('\n');
 
     /* nonce must be unique per (key, message) - it can be public and deterministic */
     puts("Generating nonce...");
     randombytes_buf(nonce, sizeof nonce);
     fputs("Nonce: ", stdout);
     print_hex(nonce, sizeof nonce);
-    putchar('\n');
 
     /* read input */
     message_len = prompt_input("a message", (char*)message, sizeof message, 1);
 
     print_hex(message, message_len);
-    putchar('\n');
 
     /* encrypt and authenticate the message */
     printf("Encrypting and authenticating with %s\n\n", crypto_box_primitive());
@@ -110,17 +104,14 @@ box(void)
     puts("Notice the prepended 16 byte authentication token\n");
     fputs("Nonce: ", stdout);
     print_hex(nonce, nonce_len);
-    putchar('\n');
     fputs("Ciphertext: ", stdout);
     print_hex(ciphertext, ciphertext_len);
-    putchar('\n');
 
     /* decrypt the message */
     puts("Alice verifies and decrypts the ciphertext...");
     ret = crypto_box_open_easy(message, ciphertext, ciphertext_len, nonce, bob_pk,
                                alice_sk);
     print_hex(message, message_len);
-    putchar('\n');
 
     print_verification(ret);
     if (ret == 0) {

demos/box_detached.c

@@ -72,31 +72,25 @@ box_detached(void)
     puts("Bob");
     fputs("Public key: ", stdout);
     print_hex(bob_pk, sizeof bob_pk);
-    putchar('\n');
     fputs("Secret key: ", stdout);
     print_hex(bob_sk, sizeof bob_sk);
-    putchar('\n');
 
     puts("Alice");
     fputs("Public key: ", stdout);
     print_hex(alice_pk, sizeof alice_pk);
-    putchar('\n');
     fputs("Secret key: ", stdout);
     print_hex(alice_sk, sizeof alice_sk);
-    putchar('\n');
 
     /* nonce must be unique per (key, message) - it can be public and deterministic */
     puts("Generating nonce...");
     randombytes_buf(nonce, sizeof nonce);
     fputs("Nonce: ", stdout);
     print_hex(nonce, sizeof nonce);
-    putchar('\n');
 
     /* read input */
     message_len = prompt_input("a message", (char*)message, sizeof message, 1);
 
     print_hex(message, message_len);
-    putchar('\n');
 
     /* encrypt and authenticate the message */
     printf("Encrypting and authenticating with %s\n\n", crypto_box_primitive());
@@ -107,20 +101,16 @@ box_detached(void)
     puts("Bob sends the nonce, the MAC and the ciphertext...\n");
     fputs("Nonce: ", stdout);
     print_hex(nonce, sizeof nonce);
-    putchar('\n');
     fputs("MAC: ", stdout);
     print_hex(mac, sizeof mac);
-    putchar('\n');
     fputs("Ciphertext: ", stdout);
     print_hex(ciphertext, message_len);
-    putchar('\n');
 
     /* decrypt the message */
     puts("Alice verifies the MAC and decrypts the ciphertext...");
     ret = crypto_box_open_detached(message, ciphertext, mac, message_len, nonce,
                                    bob_pk, alice_sk);
     print_hex(message, message_len);
-    putchar('\n');
 
     print_verification(ret);
     if (ret == 0) {

demos/generichash.c

@@ -71,7 +71,6 @@ generichash(void)
         fputs("Hash: ", stdout);
         print_hex(hash, sizeof hash);
     }
-    putchar('\n');
 }
 
 int

demos/generichash_stream.c

@@ -49,7 +49,6 @@ generichash_stream(void)
 
     fputs("Hash: ", stdout);
     print_hex(hash, sizeof hash);
-    putchar('\n');
 }
 
 int

demos/shorthash.c

@@ -49,7 +49,6 @@ shorthash(void)
     crypto_shorthash(hash, message, message_len, key);
     fputs("Hash: ", stdout);
     print_hex(hash, sizeof hash);
-    putchar('\n');
 }
 
 int

demos/sign.c

@@ -37,10 +37,8 @@ sign(void)
 
     fputs("Public key: ", stdout);
     print_hex(pk, sizeof pk);
-    putchar('\n');
     fputs("Secret key: ", stdout);
     print_hex(sk, sizeof sk);
-    putchar('\n');
     puts("The secret key, as returned by crypto_sign_keypair(), actually includes "
          "a copy of the public key, in order to avoid a scalar multiplication "
          "when signing messages.");
@@ -52,13 +50,11 @@ sign(void)
 
     printf("Signed message:");
     print_hex(message_signed, message_signed_len);
-    putchar('\n');
     printf("A %u bytes signature was prepended to the message\n",
            crypto_sign_BYTES);
 
     fputs("Signature: ", stdout);
     print_hex(message_signed, crypto_sign_BYTES);
-    putchar('\n');
     fputs("Message: ", stdout);
     fwrite(message_signed + crypto_sign_BYTES, 1U,
            message_signed_len - crypto_sign_BYTES, stdout);

demos/utils.c

@@ -12,7 +12,7 @@
 
 /*
  * print_hex() is a wrapper around sodium_bin2hex() which allocates
- * temporary memory then immediately prints the result.
+ * temporary memory then immediately prints the result followed by \n
  */
 void
 print_hex(const void *bin, const size_t bin_len)
@@ -31,7 +31,7 @@ print_hex(const void *bin, const size_t bin_len)
     if (sodium_bin2hex(hex, hex_size, bin, bin_len) == NULL) {
         abort();
     }
-    fputs(hex, stdout);
+    puts(hex);
     free(hex);
 }