ping: stop using data/bss

function                                             old     new   delta
ping_main                                            375     392     +17
unpack_tail                                          317     320      +3
ping4                                                525     528      +3
ping6                                                772     773      +1
sendping6                                             99      98      -1
sendping4                                            184     183      -1
myid                                                   2       -      -2
sendping_tail                                        154     151      -3
tsum                                                   4       -      -4
tmin                                                   4       -      -4
tmax                                                   4       -      -4
source_lsa                                             4       -      -4
pingsock                                               4       -      -4
pingcount                                              4       -      -4
ntransmitted                                           4       -      -4
nrepeats                                               4       -      -4
nreceived                                              4       -      -4
if_index                                               4       -      -4
hostname                                               8       4      -4
dotted                                                 4       -      -4
datalen                                                4       -      -4
pingaddr                                              28       -     -28
rcvd_tbl                                             128       -    -128
------------------------------------------------------------------------------
(add/remove: 0/15 grow/shrink: 4/4 up/down: 24/-215)         Total: -191 bytes
   text    data     bss     dec     hex filename
 679835    2728   16736  699299   aaba3 busybox_old
 679851    2720   16536  699107   aaae3 busybox_unstripped

diff --git a/networking/ping.c b/networking/ping.c
index 9db3180..6b5045e 100644 (file)
--- a/networking/ping.c
+++ b/networking/ping.c
@@ -235,27 +235,51 @@ enum {
 };
 
 
-static union {
-       struct sockaddr sa;
-       struct sockaddr_in sin;
+struct globals {
+       int pingsock;
+       len_and_sockaddr *source_lsa;
+       unsigned datalen;
+       int if_index;
+       unsigned long ntransmitted, nreceived, nrepeats, pingcount;
+       uint16_t myid;
+       unsigned tmin, tmax;
+       unsigned long tsum;
+       const char *hostname;
+       const char *dotted;
+       union {
+               struct sockaddr sa;
+               struct sockaddr_in sin;
 #if ENABLE_PING6
-       struct sockaddr_in6 sin6;
+               struct sockaddr_in6 sin6;
 #endif
-} pingaddr;
-static len_and_sockaddr *source_lsa;
-static int pingsock = -1;
-static unsigned datalen; /* intentionally uninitialized to work around gcc bug */
-
-static int if_index;
-
-static unsigned long ntransmitted, nreceived, nrepeats, pingcount;
-static uint16_t myid;
-static unsigned tmin = UINT_MAX, tmax;
-static unsigned long tsum;
-static char rcvd_tbl[MAX_DUP_CHK / 8];
+       } pingaddr;
+       char rcvd_tbl[MAX_DUP_CHK / 8];
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define pingsock     (G.pingsock    )
+#define source_lsa   (G.source_lsa  )
+#define datalen      (G.datalen     )
+#define if_index     (G.if_index    )
+#define ntransmitted (G.ntransmitted)
+#define nreceived    (G.nreceived   )
+#define nrepeats     (G.nrepeats    )
+#define pingcount    (G.pingcount   )
+#define myid         (G.myid        )
+#define tmin         (G.tmin        )
+#define tmax         (G.tmax        )
+#define tsum         (G.tsum        )
+#define hostname     (G.hostname    )
+#define dotted       (G.dotted      )
+#define pingaddr     (G.pingaddr    )
+#define rcvd_tbl     (G.rcvd_tbl    )
+void BUG_ping_globals_too_big(void);
+#define INIT_G() do { \
+        if (sizeof(G) > COMMON_BUFSIZE) \
+                BUG_ping_globals_too_big(); \
+       pingsock = -1; \
+       tmin = UINT_MAX; \
+} while (0)
 
-static const char *hostname;
-static const char *dotted;
 
 #define        A(bit)          rcvd_tbl[(bit)>>3]      /* identify byte in array */
 #define        B(bit)          (1 << ((bit) & 0x07))   /* identify bit in byte */
@@ -652,6 +676,8 @@ int ping_main(int argc, char **argv)
        char *opt_c, *opt_s, *opt_I;
        USE_PING6(sa_family_t af = AF_UNSPEC;)
 
+       INIT_G();
+
        datalen = DEFDATALEN; /* initialized here rather than in global scope to work around gcc bug */
 
        /* exactly one argument needed, -v and -q don't mix */