udhcpd: use ptr_to_globals for its lone global data (g_leases)

function                                             old     new   delta
udhcpd_main                                         1461    1463      +2
add_lease                                            320     318      -2
g_leases                                               4       -      -4
write_leases                                         223     214      -9
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/2 up/down: 2/-15)             Total: -13 bytes
   text	   data	    bss	    dec	    hex	filename
 933232	    481	   6856	 940569	  e5a19	busybox_old
 933223	    481	   6852	 940556	  e5a0c	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index 238542bb0..ff7450739 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -45,7 +45,7 @@
 #include "dhcpd.h"
 
 /* globals */
-struct dyn_lease *g_leases;
+#define g_leases ((struct dyn_lease*)ptr_to_globals)
 /* struct server_config_t server_config is in bb_common_bufsiz1 */
 
 /* Takes the address of the pointer to the static_leases linked list,
@@ -880,7 +880,9 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
                 server_config.max_leases = num_ips;
         }
 
-        g_leases = xzalloc(server_config.max_leases * sizeof(g_leases[0]));
+        /* this sets g_leases */
+        SET_PTR_TO_GLOBALS(xzalloc(server_config.max_leases * sizeof(g_leases[0])));
+
         read_leases(server_config.lease_file);
 
         if (udhcp_read_interface(server_config.interface,