Android: Fix the build

Include <sys/select.h> for the fd_set type. In the configure script,
check whether 'unsigned long' is the underlying type of fd_set. Use
u_long instead of ulong.

Author: bvanassche

agent/mibgroup/ip-mib/data_access/ipaddress_linux.c

@@ -50,7 +50,7 @@ int _load_v6(netsnmp_container *container, int idx_offset);
 int
 netsnmp_access_ipaddress_extra_prefix_info(int index,
                                            u_long *preferedlt,
-                                           ulong *validlt,
+                                           u_long *validlt,
                                            char *addr);
 #endif
 
@@ -523,7 +523,7 @@ netsnmp_access_other_info_get(int index, int family)
 
 int
 netsnmp_access_ipaddress_extra_prefix_info(int index, u_long *preferedlt,
-                                           ulong *validlt, char *addr)
+                                           u_long *validlt, char *addr)
 {
 
     struct {

configure

@@ -31577,7 +31577,7 @@ CFLAGS="$CFLAGS -Werror"
 
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for the type of fd_set::fds_bits" >&5
 printf %s "checking for the type of fd_set::fds_bits... " >&6; }
-for type in __fd_mask __int32_t long\ int unknown; do
+for type in __fd_mask __int32_t long 'unsigned long' unknown; do
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 

configure.d/config_project_types

@@ -66,7 +66,7 @@ netsnmp_save_CFLAGS=$CFLAGS
 CFLAGS="$CFLAGS -Werror"
 
 AC_MSG_CHECKING([for the type of fd_set::fds_bits])
-for type in __fd_mask __int32_t long\ int unknown; do
+for type in __fd_mask __int32_t long 'unsigned long' unknown; do
   AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
 #include <sys/select.h>
 #include <stddef.h>

include/net-snmp/types.h

@@ -23,6 +23,9 @@
 #endif
 
 #include <sys/types.h>
+#ifdef __ANDROID__
+#include <sys/select.h>
+#endif
 
 #if defined(WIN32) && !defined(cygwin)
 typedef HANDLE netsnmp_pid_t;