build: Check for ntohll().

This function is available on AIX.

ConfigureChecks.cmake

@@ -119,6 +119,7 @@ if (UNIX)
     check_function_exists(poll HAVE_POLL)
     check_function_exists(select HAVE_SELECT)
     check_function_exists(cfmakeraw HAVE_CFMAKERAW)
+    check_function_exists(ntohll HAVE_NTOHLL)
 endif (UNIX)
 
 set(LIBSSH_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES} CACHE INTERNAL "libssh required system libraries")

config.h.cmake

@@ -77,6 +77,9 @@
 /* Define to 1 if you have the `clock_gettime' function. */
 #cmakedefine HAVE_CLOCK_GETTIME 1
 
+/* Define to 1 if you have the `ntohll' function. */
+#cmakedefine HAVE_NTOHLL 1
+
 /*************************** LIBRARIES ***************************/
 
 /* Define to 1 if you have the `crypto' library (-lcrypto). */

src/misc.c

@@ -286,18 +286,20 @@ int ssh_is_ipaddr(const char *str) {
 
 #endif /* _WIN32 */
 
+#ifndef HAVE_NTOHLL
 uint64_t ntohll(uint64_t a) {
 #ifdef WORDS_BIGENDIAN
   return a;
-#else
+#else /* WORDS_BIGENDIAN */
   uint32_t low = (uint32_t)(a & 0xffffffff);
   uint32_t high = (uint32_t)(a >> 32);
   low = ntohl(low);
   high = ntohl(high);
 
   return ((((uint64_t) low) << 32) | ( high));
-#endif
+#endif /* WORDS_BIGENDIAN */
 }
+#endif /* HAVE_NTOHLL */
 
 char *ssh_lowercase(const char* str) {
   char *new, *p;