core: replace manual endianness swap with htobe64() call

This fixes generation of TOTP and tests on FreeBSD.

CHANGELOG.md

@@ -52,6 +52,7 @@
 - core: fix crash when deleting a bar that has no items ([#2138](https://github.com/weechat/weechat/issues/2138))
 - relay/api: fix crash when sending data to a remote buffer when the remote has been deleted ([#2157](https://github.com/weechat/weechat/issues/2157))
 - irc, xfer: fix display of input prompt in IRC private buffers and DCC chat buffers ([#2128](https://github.com/weechat/weechat/issues/2128))
+- core: fix generation of TOTP on FreeBSD ([#2171](https://github.com/weechat/weechat/issues/2171))
 - core: apply buffer properties (options weechat.buffer.*) when a buffer name is changed
 - irc: fix property "short_name" of channel buffer when the joined channel has a different case than the `/join` command
 - irc: close /list buffer when the server buffer is closed ([#2121](https://github.com/weechat/weechat/issues/2121))

src/core/core-crypto.c

@@ -38,6 +38,10 @@
 #include "core-string.h"
 #include "../plugins/plugin.h"
 
+#ifdef htonll
+#define htobe64 htonll
+#endif
+
 char *weecrypto_hash_algo_string[] = {
     "crc32",
     "md5",
@@ -520,20 +524,7 @@ weecrypto_totp_generate_internal (const char *secret, int length_secret,
     int rc, offset, length;
     unsigned long bin_code;
 
-#if __BYTE_ORDER == __BIG_ENDIAN
-    /* Big endian does not need to swap bytes here! */
-    moving_factor_swapped = moving_factor;
-#else
-    moving_factor_swapped = (moving_factor >> 56)
-        | ((moving_factor << 40) & 0x00FF000000000000)
-        | ((moving_factor << 24) & 0x0000FF0000000000)
-        | ((moving_factor << 8) & 0x000000FF00000000)
-        | ((moving_factor >> 8) & 0x00000000FF000000)
-        | ((moving_factor >> 24) & 0x0000000000FF0000)
-        | ((moving_factor >> 40) & 0x000000000000FF00)
-        | (moving_factor << 56);
-#endif
-
+    moving_factor_swapped = htobe64 (moving_factor);
     rc = weecrypto_hmac (secret, length_secret,
                          &moving_factor_swapped, sizeof (moving_factor_swapped),
                          GCRY_MD_SHA1,