networking/interface.c: huke remaining big statics; use malloc for INET[6]_rresolve

return value. Went thru callers and adjusted them - code got smaller too.

function                                             old     new   delta
ip_port_str                                            -     126    +126
INET6_rresolve                                       165     182     +17
static.cache                                          20      24      +4
route_main                                          2092    2091      -1
INET_sprint                                           61      59      -2
INET_nn                                                4       -      -4
INET6_sprint                                          59      53      -6
udp_do_one                                           518     508     -10
tcp_do_one                                           433     423     -10
raw_do_one                                           494     484     -10
traceroute_main                                     4117    4105     -12
INET_rresolve                                        334     321     -13
bb_displayroutes                                     494     456     -38
snprint_ip_port                                      244       -    -244
static.buff                                          264      16    -248
------------------------------------------------------------------------------
(add/remove: 1/2 grow/shrink: 2/10 up/down: 147/-598)        Total: -451 bytes

size busybox_old busybox_unstripped
   text    data     bss     dec     hex filename
 751073    3048   14688  768809   bbb29 busybox_old
 750873    3048   14440  768361   bb969 busybox_unstripped

6 files changed, 112 insertions, 136 deletions

diff --git a/include/inet_common.h b/include/inet_common.h
index fa48fdffa..eb4cb7325 100644
--- a/include/inet_common.h
+++ b/include/inet_common.h
@@ -18,9 +18,9 @@ int INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst);
  *          & 0x4000: host instead of net,
  *          & 0x0fff: don't resolve
  */
-int INET_rresolve(char *name, size_t len, struct sockaddr_in *s_in,
-        int numeric, unsigned int netmask);
-
 
 int INET6_resolve(const char *name, struct sockaddr_in6 *sin6);
-int INET6_rresolve(char *name, size_t len, struct sockaddr_in6 *sin6, int numeric);
+
+/* These return malloced string */
+char *INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t netmask);
+char *INET6_rresolve(struct sockaddr_in6 *sin6, int numeric);
diff --git a/libbb/inet_common.c b/libbb/inet_common.c
index 44b44a4cc..8449201ab 100644
--- a/libbb/inet_common.c
+++ b/libbb/inet_common.c
@@ -72,26 +72,24 @@ int INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst)
         return 0;
 }
 
-/* cache */
-struct addr {
-        struct sockaddr_in addr;
-        char *name;
-        int host;
-        struct addr *next;
-};
-
-static struct addr *INET_nn = NULL;     /* addr-to-name cache */
 
 /* numeric: & 0x8000: default instead of *,
  *          & 0x4000: host instead of net,
  *          & 0x0fff: don't resolve
  */
-int INET_rresolve(char *name, size_t len, struct sockaddr_in *s_in,
-                                  int numeric, unsigned int netmask)
+char *INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t netmask)
 {
-        struct hostent *ent;
-        struct netent *np;
+        /* addr-to-name cache */
+        struct addr {
+                struct addr *next;
+                struct sockaddr_in addr;
+                int host;
+                char name[1];
+        };
+        static struct addr *cache = NULL;
+
         struct addr *pn;
+        char *name;
         uint32_t ad, host_ad;
         int host = 0;
 
@@ -102,7 +100,7 @@ int INET_rresolve(char *name, size_t len, struct sockaddr_in *s_in,
                                   s_in->sin_family);
 #endif
                 errno = EAFNOSUPPORT;
-                return -1;
+                return NULL;
         }
         ad = s_in->sin_addr.s_addr;
 #ifdef DEBUG
@@ -111,62 +109,58 @@ int INET_rresolve(char *name, size_t len, struct sockaddr_in *s_in,
         if (ad == INADDR_ANY) {
                 if ((numeric & 0x0FFF) == 0) {
                         if (numeric & 0x8000)
-                                safe_strncpy(name, bb_str_default, len);
-                        else
-                                safe_strncpy(name, "*", len);
-                        return 0;
+                                return xstrdup(bb_str_default);
+                        return xstrdup("*");
                 }
         }
-        if (numeric & 0x0FFF) {
-                safe_strncpy(name, inet_ntoa(s_in->sin_addr), len);
-                return 0;
-        }
+        if (numeric & 0x0FFF)
+                return xstrdup(inet_ntoa(s_in->sin_addr));
 
         if ((ad & (~netmask)) != 0 || (numeric & 0x4000))
                 host = 1;
-        pn = INET_nn;
-        while (pn != NULL) {
+        pn = cache;
+        while (pn) {
                 if (pn->addr.sin_addr.s_addr == ad && pn->host == host) {
-                        safe_strncpy(name, pn->name, len);
 #ifdef DEBUG
                         bb_error_msg("rresolve: found %s %08x in cache",
                                           (host ? "host" : "net"), (unsigned)ad);
 #endif
-                        return 0;
+                        return xstrdup(pn->name);
                 }
                 pn = pn->next;
         }
 
         host_ad = ntohl(ad);
-        np = NULL;
-        ent = NULL;
+        name = NULL;
         if (host) {
+                struct hostent *ent;
 #ifdef DEBUG
                 bb_error_msg("gethostbyaddr (%08x)", (unsigned)ad);
 #endif
                 ent = gethostbyaddr((char *) &ad, 4, AF_INET);
-                if (ent != NULL) {
-                        safe_strncpy(name, ent->h_name, len);
-                }
+                if (ent)
+                        name = xstrdup(ent->h_name);
         } else {
+                /* Hmmm... this is very rare to have named nets,
+                 * and this getnetbyaddr() call is the only one in bbox.
+                 * Maybe get rid of or make configurable? */
+                struct netent *np;
 #ifdef DEBUG
                 bb_error_msg("getnetbyaddr (%08x)", (unsigned)host_ad);
 #endif
                 np = getnetbyaddr(host_ad, AF_INET);
-                if (np != NULL) {
-                        safe_strncpy(name, np->n_name, len);
-                }
-        }
-        if (!ent && !np) {
-                safe_strncpy(name, inet_ntoa(s_in->sin_addr), len);
+                if (np)
+                        name = xstrdup(np->n_name);
         }
-        pn = xmalloc(sizeof(struct addr));
+        if (!name)
+                name = xstrdup(inet_ntoa(s_in->sin_addr));
+        pn = xmalloc(sizeof(*pn) + strlen(name)); /* no '+ 1', it's already accounted for */
+        pn->next = cache;
         pn->addr = *s_in;
-        pn->next = INET_nn;
         pn->host = host;
-        pn->name = xstrdup(name);
-        INET_nn = pn;
-        return 0;
+        strcpy(pn->name, name);
+        cache = pn;
+        return name;
 }
 
 #ifdef CONFIG_FEATURE_IPV6
@@ -195,9 +189,9 @@ int INET6_resolve(const char *name, struct sockaddr_in6 *sin6)
 #endif
 
 
-int INET6_rresolve(char *name, size_t len, struct sockaddr_in6 *sin6,
-                                   int numeric)
+char *INET6_rresolve(struct sockaddr_in6 *sin6, int numeric)
 {
+        char name[128];
         int s;
 
         /* Grmpf. -FvK */
@@ -207,29 +201,25 @@ int INET6_rresolve(char *name, size_t len, struct sockaddr_in6 *sin6,
                                   sin6->sin6_family);
 #endif
                 errno = EAFNOSUPPORT;
-                return -1;
+                return NULL;
         }
         if (numeric & 0x7FFF) {
-                inet_ntop(AF_INET6, &sin6->sin6_addr, name, len);
-                return 0;
+                inet_ntop(AF_INET6, &sin6->sin6_addr, name, sizeof(name));
+                return xstrdup(name);
         }
         if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
-                if (numeric & 0x8000) {
-                        strcpy(name, bb_str_default);
-                } else {
-                        name[0] = '*';
-                        name[1] = '\0';
-                }
-                return 0;
+                if (numeric & 0x8000)
+                        return xstrdup(bb_str_default);
+                return xstrdup("*");
         }
 
         s = getnameinfo((struct sockaddr *) sin6, sizeof(struct sockaddr_in6),
-                                name, len, NULL, 0, 0);
+                                name, sizeof(name), NULL, 0, 0);
         if (s) {
                 bb_error_msg("getnameinfo failed");
-                return -1;
+                return NULL;
         }
-        return 0;
+        return xstrdup(name);
 }
 
 #endif                                                  /* CONFIG_FEATURE_IPV6 */
diff --git a/networking/interface.c b/networking/interface.c
index f8721f409..204febf7d 100644
--- a/networking/interface.c
+++ b/networking/interface.c
@@ -84,13 +84,12 @@ struct in6_ifreq {
 /* Display an Internet socket address. */
 static const char *INET_sprint(struct sockaddr *sap, int numeric)
 {
-        static char buff[128];
+        static char *buff;
 
+        free(buff);
         if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
                 return "[NONE SET]";
-        if (INET_rresolve(buff, sizeof(buff), (struct sockaddr_in *) sap,
-                                          numeric, 0xffffff00) != 0)
-                return NULL;
+        buff = INET_rresolve((struct sockaddr_in *) sap, numeric, 0xffffff00);
         return buff;
 }
 
@@ -167,12 +166,12 @@ static const struct aftype inet_aftype = {
 /* dirty! struct sockaddr usually doesn't suffer for inet6 addresses, fst. */
 static const char *INET6_sprint(struct sockaddr *sap, int numeric)
 {
-        static char buff[128];
+        static char *buff;
 
+        free(buff);
         if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
                 return "[NONE SET]";
-        if (INET6_rresolve(buff, sizeof(buff), (struct sockaddr_in6 *) sap, numeric))
-                return "[UNKNOWN]";
+        buff = INET6_rresolve((struct sockaddr_in6 *) sap, numeric);
         return buff;
 }
 
diff --git a/networking/netstat.c b/networking/netstat.c
index d6c10b07b..746e25091 100644
--- a/networking/netstat.c
+++ b/networking/netstat.c
@@ -120,50 +120,33 @@ static void build_ipv4_addr(char* local_addr, struct sockaddr_in* localaddr)
         ((struct sockaddr *) localaddr)->sa_family = AF_INET;
 }
 
-static const char *get_sname(int port, const char *proto, int num)
+static const char *get_sname(int port, const char *proto, int numeric)
 {
-        /* hummm, we return static buffer here!! */
-        const char *str = itoa(ntohs(port));
-        if (!num) {
+        if (!port)
+                return "*";
+        if (!numeric) {
                 struct servent *se = getservbyport(port, proto);
                 if (se)
-                        str = se->s_name;
+                        return se->s_name;
         }
-        if (!port) {
-                str = "*";
-        }
-        return str;
+        /* hummm, we may return static buffer here!! */
+        return itoa(ntohs(port));
 }
 
-static void snprint_ip_port(char *ip_port, int size, struct sockaddr *addr, int port, const char *proto, int numeric)
+static char *ip_port_str(struct sockaddr *addr, int port, const char *proto, int numeric)
 {
-        const char *port_name;
-        int max_len;
-        int port_name_len;
+        enum { salen = USE_FEATURE_IPV6(sizeof(struct sockaddr_in6)) SKIP_FEATURE_IPV6(sizeof(struct sockaddr_in)) };
+        char *host, *host_port;
 
-// TODO: replace by xmalloc_sockaddr2host?
-#if ENABLE_FEATURE_IPV6
-        if (addr->sa_family == AF_INET6) {
-                INET6_rresolve(ip_port, size, (struct sockaddr_in6 *)addr,
-                        (numeric & NETSTAT_NUMERIC) ? 0x0fff : 0);
-        } else
-#endif
-        {
-                INET_rresolve(ip_port, size, (struct sockaddr_in *)addr,
-                        0x4000 | ((numeric & NETSTAT_NUMERIC) ? 0x0fff : 0),
-                        0xffffffff);
-        }
-        port_name = get_sname(htons(port), proto, numeric);
-
-        max_len = (option_mask32 & OPT_widedisplay)
-                        ? (PRINT_IP_MAX_SIZE_WIDE - 1)
-                        : (PRINT_IP_MAX_SIZE - 1);
-        port_name_len = strlen(port_name);
-        if ((strlen(ip_port) + port_name_len) > max_len)
-                ip_port[max_len - port_name_len] = '\0';
-        ip_port += strlen(ip_port);
-        *ip_port++ = ':';
-        strcpy(ip_port, port_name);
+        /* Code which used "*" for INADDR_ANY is removed: it's ambiguous in IPv6,
+         * while "0.0.0.0" is not. */
+
+        host = numeric ? xmalloc_sockaddr2dotted_noport(addr, salen)
+                       : xmalloc_sockaddr2host_noport(addr, salen);
+
+        host_port = xasprintf("%s:%s", host, get_sname(htons(port), proto, numeric));
+        free(host);
+        return host_port;
 }
 
 static void tcp_do_one(int lnr, const char *line)
@@ -206,14 +189,16 @@ static void tcp_do_one(int lnr, const char *line)
         if ((rem_port && (flags & NETSTAT_CONNECTED))
          || (!rem_port && (flags & NETSTAT_LISTENING))
         ) {
-                snprint_ip_port(local_addr, sizeof(local_addr),
+                char *l = ip_port_str(
                                 (struct sockaddr *) &localaddr, local_port,
                                 "tcp", flags & NETSTAT_NUMERIC);
-                snprint_ip_port(rem_addr, sizeof(rem_addr),
+                char *r = ip_port_str(
                                 (struct sockaddr *) &remaddr, rem_port,
                                 "tcp", flags & NETSTAT_NUMERIC);
                 printf(net_conn_line,
-                        "tcp", rxq, txq, local_addr, rem_addr, tcp_state[state]);
+                        "tcp", rxq, txq, l, r, tcp_state[state]);
+                free(l);
+                free(r);
         }
 }
 
@@ -285,14 +270,16 @@ static void udp_do_one(int lnr, const char *line)
                 if ((have_remaddr && (flags & NETSTAT_CONNECTED))
                  || (!have_remaddr && (flags & NETSTAT_LISTENING))
                 ) {
-                        snprint_ip_port(local_addr, sizeof(local_addr),
+                        char *l = ip_port_str(
                                 (struct sockaddr *) &localaddr, local_port,
                                 "udp", flags & NETSTAT_NUMERIC);
-                        snprint_ip_port(rem_addr, sizeof(rem_addr),
+                        char *r = ip_port_str(
                                 (struct sockaddr *) &remaddr, rem_port,
                                 "udp", flags & NETSTAT_NUMERIC);
                         printf(net_conn_line,
-                                "udp", rxq, txq, local_addr, rem_addr, state_str);
+                                "udp", rxq, txq, l, r, state_str);
+                        free(l);
+                        free(r);
                 }
         }
 }
@@ -339,14 +326,16 @@ static void raw_do_one(int lnr, const char *line)
                 if ((have_remaddr && (flags & NETSTAT_CONNECTED))
                  || (!have_remaddr && (flags & NETSTAT_LISTENING))
                 ) {
-                        snprint_ip_port(local_addr, sizeof(local_addr),
+                        char *l = ip_port_str(
                                 (struct sockaddr *) &localaddr, local_port,
                                 "raw", flags & NETSTAT_NUMERIC);
-                        snprint_ip_port(rem_addr, sizeof(rem_addr),
+                        char *r = ip_port_str(
                                 (struct sockaddr *) &remaddr, rem_port,
                                 "raw", flags & NETSTAT_NUMERIC);
                         printf(net_conn_line,
-                                "raw", rxq, txq, local_addr, rem_addr, itoa(state));
+                                "raw", rxq, txq, l, r, itoa(state));
+                        free(l);
+                        free(r);
                 }
         }
 }
diff --git a/networking/route.c b/networking/route.c
index 881332b9f..b5490ddd8 100644
--- a/networking/route.c
+++ b/networking/route.c
@@ -478,7 +478,7 @@ static void set_flags(char *flagstr, int flags)
 /* also used in netstat */
 void bb_displayroutes(int noresolve, int netstatfmt)
 {
-        char devname[64], flags[16], sdest[16], sgw[16];
+        char devname[64], flags[16], *sdest, *sgw;
         unsigned long d, g, m;
         int flgs, ref, use, metric, mtu, win, ir;
         struct sockaddr_in s_addr;
@@ -520,15 +520,14 @@ void bb_displayroutes(int noresolve, int netstatfmt)
                 memset(&s_addr, 0, sizeof(struct sockaddr_in));
                 s_addr.sin_family = AF_INET;
                 s_addr.sin_addr.s_addr = d;
-                INET_rresolve(sdest, sizeof(sdest), &s_addr,
-                                          (noresolve | 0x8000), m);     /* Default instead of *. */
-
+                sdest = INET_rresolve(&s_addr, (noresolve | 0x8000), m); /* 'default' instead of '*' */
                 s_addr.sin_addr.s_addr = g;
-                INET_rresolve(sgw, sizeof(sgw), &s_addr,
-                                          (noresolve | 0x4000), m);     /* Host instead of net. */
-
+                sgw = INET_rresolve(&s_addr, (noresolve | 0x4000), m); /* Host instead of net */
                 mask.s_addr = m;
-                printf("%-16s%-16s%-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
+                /* "%15.15s" truncates hostnames, do we really want that? */
+                printf("%-15.15s %-15.15s %-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
+                free(sdest);
+                free(sgw);
                 if (netstatfmt) {
                         printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
                 } else {
@@ -541,7 +540,7 @@ void bb_displayroutes(int noresolve, int netstatfmt)
 
 static void INET6_displayroutes(int noresolve)
 {
-        char addr6[128], naddr6[128];
+        char addr6[128], *naddr6;
         /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
          * We read the non-delimited strings into the tail of the buffer
          * using fscanf and then modify the buffer by shifting forward
@@ -581,7 +580,7 @@ static void INET6_displayroutes(int noresolve)
 
                         do {
                                 if (!*p) {
-                                        if (i==40) { /* nul terminator for 1st address? */
+                                        if (i == 40) { /* nul terminator for 1st address? */
                                                 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
                                                 ++p;    /* Skip and continue. */
                                                 continue;
@@ -606,18 +605,19 @@ static void INET6_displayroutes(int noresolve)
                         inet_pton(AF_INET6, addr6x + r,
                                           (struct sockaddr *) &snaddr6.sin6_addr);
                         snaddr6.sin6_family = AF_INET6;
-                        INET6_rresolve(naddr6, sizeof(naddr6),
-                                                   (struct sockaddr_in6 *) &snaddr6,
+                        naddr6 = INET6_rresolve((struct sockaddr_in6 *) &snaddr6,
                                                    0x0fff /* Apparently, upstream never resolves. */
                                                    );
 
                         if (!r) {                       /* 1st pass */
                                 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
                                 r += 40;
+                                free(naddr6);
                         } else {                        /* 2nd pass */
                                 /* Print the info. */
                                 printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
-                                                  addr6, naddr6, flags, metric, refcnt, use, iface);
+                                                addr6, naddr6, flags, metric, refcnt, use, iface);
+                                free(naddr6);
                                 break;
                         }
                 } while (1);
diff --git a/networking/traceroute.c b/networking/traceroute.c
index 9fc15d390..577738a97 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -802,22 +802,20 @@ packet_ok(unsigned char *buf, int cc, struct sockaddr_in *from, int seq)
  * numeric value, otherwise try for symbolic name.
  */
 static inline void
-inetname(struct sockaddr_in *from)
+print_inetname(struct sockaddr_in *from)
 {
-        const char *n = NULL;
         const char *ina;
-        char name[257];
 
-        if (!nflag && from->sin_addr.s_addr != INADDR_ANY) {
-                if (INET_rresolve(name, sizeof(name), from, 0x4000,
-                                                0xffffffff) >= 0)
-                        n = name;
-        }
         ina = inet_ntoa(from->sin_addr);
         if (nflag)
                 printf(" %s", ina);
-        else
+        else {
+                char *n = NULL;
+                if (from->sin_addr.s_addr != INADDR_ANY)
+                        n = xmalloc_sockaddr2host_noport((struct sockaddr*)from, sizeof(*from));
                 printf(" %s (%s)", (n ? n : ina), ina);
+                free(n);
+        }
 }
 
 static inline void
@@ -830,7 +828,7 @@ print(unsigned char *buf, int cc, struct sockaddr_in *from)
         hlen = ip->ip_hl << 2;
         cc -= hlen;
 
-        inetname(from);
+        print_inetname(from);
 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
         if (verbose)
                 printf(" %d bytes to %s", cc, inet_ntoa(ip->ip_dst));