Sparse fixes: NULL use, header order, ANSI prototypes, static

Fix Sparse warnings:
 * use NULL instead of plain 0
 * rearrange header include order to avoid redefining types accidentally
 * ANSIfy SLIRP
 * avoid "restrict" keyword
 * add static



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6736 c046a42c-6fe2-441c-8c8c-71466251a162

13 files changed, 94 insertions, 176 deletions

diff --git a/slirp/if.c b/slirp/if.c
index 0e10f3e6d9..17f8a73378 100644
--- a/slirp/if.c
+++ b/slirp/if.c
@@ -32,7 +32,7 @@ ifs_remque(struct mbuf *ifm)
 }
 
 void
-if_init()
+if_init(void)
 {
 	if_fastq.ifq_next = if_fastq.ifq_prev = &if_fastq;
 	if_batchq.ifq_next = if_batchq.ifq_prev = &if_batchq;
@@ -133,9 +133,7 @@ if_input(ttyp)
  * it'll temporarily get downgraded to the batchq)
  */
 void
-if_output(so, ifm)
-	struct socket *so;
-	struct mbuf *ifm;
+if_output(struct socket *so, struct mbuf *ifm)
 {
 	struct mbuf *ifq;
 	int on_fastq = 1;
diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c
index 4b27facf18..61dcaf821b 100644
--- a/slirp/ip_icmp.c
+++ b/slirp/ip_icmp.c
@@ -68,9 +68,7 @@ static const int icmp_flush[19] = {
  * Process a received ICMP message.
  */
 void
-icmp_input(m, hlen)
-     struct mbuf *m;
-     int hlen;
+icmp_input(struct mbuf *m, int hlen)
 {
   register struct icmp *icp;
   register struct ip *ip=mtod(m, struct ip *);
@@ -319,8 +317,7 @@ end_error:
  * Reflect the ip packet back to the source
  */
 void
-icmp_reflect(m)
-     struct mbuf *m;
+icmp_reflect(struct mbuf *m)
 {
   register struct ip *ip = mtod(m, struct ip *);
   int hlen = ip->ip_hl << 2;
diff --git a/slirp/ip_input.c b/slirp/ip_input.c
index 505149a33e..c37412e8cf 100644
--- a/slirp/ip_input.c
+++ b/slirp/ip_input.c
@@ -60,7 +60,7 @@ static void ip_deq(register struct ipasfrag *p);
  * All protocols not implemented in kernel go to raw IP protocol handler.
  */
 void
-ip_init()
+ip_init(void)
 {
 	ipq.ip_link.next = ipq.ip_link.prev = &ipq.ip_link;
 	ip_id = tt.tv_sec & 0xffff;
@@ -73,8 +73,7 @@ ip_init()
  * try to reassemble.  Process options.  Pass to next level.
  */
 void
-ip_input(m)
-	struct mbuf *m;
+ip_input(struct mbuf *m)
 {
 	register struct ip *ip;
 	int hlen;
@@ -222,7 +221,7 @@ ip_input(m)
 		if (ip->ip_tos & 1 || ip->ip_off) {
 			STAT(ipstat.ips_fragments++);
 			ip = ip_reass(ip, fp);
-			if (ip == 0)
+                        if (ip == NULL)
 				return;
 			STAT(ipstat.ips_reassembled++);
 			m = dtom(ip);
@@ -289,7 +288,7 @@ ip_reass(register struct ip *ip, register struct ipq *fp)
 	/*
 	 * If first fragment to arrive, create a reassembly queue.
 	 */
-	if (fp == 0) {
+        if (fp == NULL) {
 	  struct mbuf *t;
 	  if ((t = m_get()) == NULL) goto dropfrag;
 	  fp = mtod(t, struct ipq *);
@@ -357,11 +356,11 @@ insert:
 	for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link;
             q = q->ipf_next) {
 		if (q->ipf_off != next)
-			return (0);
+                        return NULL;
 		next += q->ipf_len;
 	}
 	if (((struct ipasfrag *)(q->ipf_prev))->ipf_tos & 1)
-		return (0);
+                return NULL;
 
 	/*
 	 * Reassembly is complete; concatenate fragments.
@@ -414,7 +413,7 @@ insert:
 dropfrag:
 	STAT(ipstat.ips_fragdropped++);
 	m_freem(m);
-	return (0);
+        return NULL;
 }
 
 /*
@@ -466,7 +465,7 @@ ip_deq(register struct ipasfrag *p)
  * queue, discard it.
  */
 void
-ip_slowtimo()
+ip_slowtimo(void)
 {
     struct qlink *l;
 
@@ -474,7 +473,7 @@ ip_slowtimo()
 
     l = ipq.ip_link.next;
 
-	if (l == 0)
+        if (l == NULL)
 	   return;
 
 	while (l != &ipq.ip_link) {
@@ -702,9 +701,7 @@ bad:
  * (XXX) should be deleted; last arg currently ignored.
  */
 void
-ip_stripoptions(m, mopt)
-	register struct mbuf *m;
-	struct mbuf *mopt;
+ip_stripoptions(register struct mbuf *m, struct mbuf *mopt)
 {
 	register int i;
 	struct ip *ip = mtod(m, struct ip *);
diff --git a/slirp/ip_output.c b/slirp/ip_output.c
index 9538db9895..5bce520612 100644
--- a/slirp/ip_output.c
+++ b/slirp/ip_output.c
@@ -53,9 +53,7 @@ u_int16_t ip_id;
  * The mbuf opt, if present, will not be freed.
  */
 int
-ip_output(so, m0)
-	struct socket *so;
-	struct mbuf *m0;
+ip_output(struct socket *so, struct mbuf *m0)
 {
 	register struct ip *ip;
 	register struct mbuf *m = m0;
@@ -135,7 +133,7 @@ ip_output(so, m0)
 	for (off = hlen + len; off < (u_int16_t)ip->ip_len; off += len) {
 	  register struct ip *mhip;
 	  m = m_get();
-	  if (m == 0) {
+          if (m == NULL) {
 	    error = -1;
 	    STAT(ipstat.ips_odropped++);
 	    goto sendorfree;
@@ -185,7 +183,7 @@ ip_output(so, m0)
 sendorfree:
 	for (m = m0; m; m = m0) {
 		m0 = m->m_nextpkt;
-		m->m_nextpkt = 0;
+                m->m_nextpkt = NULL;
 		if (error == 0)
 			if_output(so, m);
 		else
diff --git a/slirp/libslirp.h b/slirp/libslirp.h
index 6c5db54c95..ac3df7818e 100644
--- a/slirp/libslirp.h
+++ b/slirp/libslirp.h
@@ -5,7 +5,7 @@
 extern "C" {
 #endif
 
-void slirp_init(int restrict, char *special_ip);
+void slirp_init(int restricted, char *special_ip);
 
 void slirp_select_fill(int *pnfds,
                        fd_set *readfds, fd_set *writefds, fd_set *xfds);
diff --git a/slirp/mbuf.c b/slirp/mbuf.c
index 655de41805..1d30a630c6 100644
--- a/slirp/mbuf.c
+++ b/slirp/mbuf.c
@@ -29,7 +29,7 @@ int mbuf_max = 0;
 #define SLIRP_MSIZE (IF_MTU + IF_MAXLINKHDR + sizeof(struct m_hdr ) + 6)
 
 void
-m_init()
+m_init(void)
 {
 	m_freelist.m_next = m_freelist.m_prev = &m_freelist;
 	m_usedlist.m_next = m_usedlist.m_prev = &m_usedlist;
@@ -44,7 +44,7 @@ m_init()
  * which tells m_free to actually free() it
  */
 struct mbuf *
-m_get()
+m_get(void)
 {
 	register struct mbuf *m;
 	int flags = 0;
@@ -72,16 +72,15 @@ m_get()
 	m->m_size = SLIRP_MSIZE - sizeof(struct m_hdr);
 	m->m_data = m->m_dat;
 	m->m_len = 0;
-	m->m_nextpkt = 0;
-	m->m_prevpkt = 0;
+        m->m_nextpkt = NULL;
+        m->m_prevpkt = NULL;
 end_error:
 	DEBUG_ARG("m = %lx", (long )m);
 	return m;
 }
 
 void
-m_free(m)
-	struct mbuf *m;
+m_free(struct mbuf *m)
 {
 
   DEBUG_CALL("m_free");
@@ -115,8 +114,7 @@ m_free(m)
  * an M_EXT data segment
  */
 void
-m_cat(m, n)
-	register struct mbuf *m, *n;
+m_cat(struct mbuf *m, struct mbuf *n)
 {
 	/*
 	 * If there's no room, realloc
@@ -133,9 +131,7 @@ m_cat(m, n)
 
 /* make m size bytes large */
 void
-m_inc(m, size)
-        struct mbuf *m;
-        int size;
+m_inc(struct mbuf *m, int size)
 {
 	int datasize;
 
@@ -170,9 +166,7 @@ m_inc(m, size)
 
 
 void
-m_adj(m, len)
-	struct mbuf *m;
-	int len;
+m_adj(struct mbuf *m, int len)
 {
 	if (m == NULL)
 		return;
@@ -192,9 +186,7 @@ m_adj(m, len)
  * Copy len bytes from m, starting off bytes into n
  */
 int
-m_copy(n, m, off, len)
-	struct mbuf *n, *m;
-	int off, len;
+m_copy(struct mbuf *n, struct mbuf *m, int off, int len)
 {
 	if (len > M_FREEROOM(n))
 		return -1;
@@ -211,8 +203,7 @@ m_copy(n, m, off, len)
  * Fortunately, it's not used often
  */
 struct mbuf *
-dtom(dat)
-	void *dat;
+dtom(void *dat)
 {
 	struct mbuf *m;
 
diff --git a/slirp/misc.c b/slirp/misc.c
index b4c73d1da8..6620391850 100644
--- a/slirp/misc.c
+++ b/slirp/misc.c
@@ -70,7 +70,7 @@ redir_x(inaddr, start_port, display, screen)
  * Get our IP address and put it in our_addr
  */
 void
-getouraddr()
+getouraddr(void)
 {
 	char buff[256];
 	struct hostent *he = NULL;
@@ -89,8 +89,7 @@ struct quehead {
 };
 
 inline void
-insque(a, b)
-	void *a, *b;
+insque(void *a, void *b)
 {
 	register struct quehead *element = (struct quehead *) a;
 	register struct quehead *head = (struct quehead *) b;
@@ -102,8 +101,7 @@ insque(a, b)
 }
 
 inline void
-remque(a)
-     void *a;
+remque(void *a)
 {
   register struct quehead *element = (struct quehead *) a;
   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
@@ -116,12 +114,7 @@ remque(a)
 
 
 int
-add_exec(ex_ptr, do_pty, exec, addr, port)
-	struct ex_list **ex_ptr;
-	int do_pty;
-	char *exec;
-	int addr;
-	int port;
+add_exec(struct ex_list **ex_ptr, int do_pty, char *exec, int addr, int port)
 {
 	struct ex_list *tmp_ptr;
 
@@ -363,7 +356,7 @@ fork_exec(struct socket *so, const char *ex, int do_pty)
 			argv[i++] = strdup(curarg);
 		   } while (c);
 
-		argv[i] = 0;
+                argv[i] = NULL;
 		execvp(argv[0], (char **)argv);
 
 		/* Ooops, failed, let's tell the user why */
@@ -402,9 +395,9 @@ fork_exec(struct socket *so, const char *ex, int do_pty)
 		fd_nonblock(so->s);
 
 		/* Append the telnet options now */
-		if (so->so_m != 0 && do_pty == 1)  {
+                if (so->so_m != NULL && do_pty == 1)  {
 			sbappend(so, so->so_m);
-			so->so_m = 0;
+                        so->so_m = NULL;
 		}
 
 		return 1;
@@ -764,8 +757,7 @@ sprintf_len(va_alist) va_dcl
 #endif
 
 void
-u_sleep(usec)
-	int usec;
+u_sleep(int usec)
 {
 	struct timeval t;
 	fd_set fdset;
@@ -783,8 +775,7 @@ u_sleep(usec)
  */
 
 void
-fd_nonblock(fd)
-	int fd;
+fd_nonblock(int fd)
 {
 #ifdef FIONBIO
 	int opt = 1;
@@ -800,8 +791,7 @@ fd_nonblock(fd)
 }
 
 void
-fd_block(fd)
-	int fd;
+fd_block(int fd)
 {
 #ifdef FIONBIO
 	int opt = 0;
diff --git a/slirp/sbuf.c b/slirp/sbuf.c
index 2e6e2b2140..5375414f26 100644
--- a/slirp/sbuf.c
+++ b/slirp/sbuf.c
@@ -18,16 +18,13 @@ static void sbappendsb(struct sbuf *sb, struct mbuf *m);
  */
 
 void
-sbfree(sb)
-	struct sbuf *sb;
+sbfree(struct sbuf *sb)
 {
 	free(sb->sb_data);
 }
 
 void
-sbdrop(sb, num)
-	struct sbuf *sb;
-	int num;
+sbdrop(struct sbuf *sb, int num)
 {
 	/*
 	 * We can only drop how much we have
@@ -43,9 +40,7 @@ sbdrop(sb, num)
 }
 
 void
-sbreserve(sb, size)
-	struct sbuf *sb;
-	int size;
+sbreserve(struct sbuf *sb, int size)
 {
 	if (sb->sb_data) {
 		/* Already alloced, realloc if necessary */
@@ -74,9 +69,7 @@ sbreserve(sb, size)
  * (the socket is non-blocking, so we won't hang)
  */
 void
-sbappend(so, m)
-	struct socket *so;
-	struct mbuf *m;
+sbappend(struct socket *so, struct mbuf *m)
 {
 	int ret = 0;
 
@@ -173,11 +166,7 @@ sbappendsb(struct sbuf *sb, struct mbuf *m)
  * done in sbdrop when the data is acked
  */
 void
-sbcopy(sb, off, len, to)
-	struct sbuf *sb;
-	int off;
-	int len;
-	char *to;
+sbcopy(struct sbuf *sb, int off, int len, char *to)
 {
 	char *from;
 
diff --git a/slirp/slirp.c b/slirp/slirp.c
index 0394496ab3..4ca35b28f6 100644
--- a/slirp/slirp.c
+++ b/slirp/slirp.c
@@ -50,7 +50,7 @@ static const uint8_t zero_ethaddr[6] = { 0, 0, 0, 0, 0, 0 };
 
 const char *slirp_special_ip = CTL_SPECIAL;
 int slirp_restrict;
-int do_slowtimo;
+static int do_slowtimo;
 int link_up;
 struct timeval tt;
 FILE *lfd;
@@ -171,7 +171,7 @@ static void slirp_cleanup(void)
 static void slirp_state_save(QEMUFile *f, void *opaque);
 static int slirp_state_load(QEMUFile *f, void *opaque, int version_id);
 
-void slirp_init(int restrict, char *special_ip)
+void slirp_init(int restricted, char *special_ip)
 {
     //    debug_init("/tmp/slirp.log", DEBUG_DEFAULT);
 
@@ -184,7 +184,7 @@ void slirp_init(int restrict, char *special_ip)
 #endif
 
     link_up = 1;
-    slirp_restrict = restrict;
+    slirp_restrict = restricted;
 
     if_init();
     ip_init();
@@ -228,7 +228,7 @@ static void updtime(void)
 #else
 static void updtime(void)
 {
-	gettimeofday(&tt, 0);
+        gettimeofday(&tt, NULL);
 
 	curtime = (u_int)tt.tv_sec * (u_int)1000;
 	curtime += (u_int)tt.tv_usec / (u_int)1000;
diff --git a/slirp/socket.c b/slirp/socket.c
index 9def541dae..1c5dee35c6 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -25,12 +25,8 @@ so_init()
 #endif
 
 struct socket *
-solookup(head, laddr, lport, faddr, fport)
-	struct socket *head;
-	struct in_addr laddr;
-	u_int lport;
-	struct in_addr faddr;
-	u_int fport;
+solookup(struct socket *head, struct in_addr laddr, u_int lport,
+         struct in_addr faddr, u_int fport)
 {
 	struct socket *so;
 
@@ -54,7 +50,7 @@ solookup(head, laddr, lport, faddr, fport)
  * insque() it into the correct linked-list
  */
 struct socket *
-socreate()
+socreate(void)
 {
   struct socket *so;
 
@@ -71,8 +67,7 @@ socreate()
  * remque and free a socket, clobber cache
  */
 void
-sofree(so)
-	struct socket *so;
+sofree(struct socket *so)
 {
   if (so->so_emu==EMU_RSH && so->extra) {
 	sofree(so->extra);
@@ -158,8 +153,7 @@ size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
  * a read() of 0 (or less) means it's disconnected
  */
 int
-soread(so)
-	struct socket *so;
+soread(struct socket *so)
 {
 	int n, nn;
 	struct sbuf *sb = &so->so_snd;
@@ -269,8 +263,7 @@ err:
  * in the send buffer is sent as urgent data
  */
 void
-sorecvoob(so)
-	struct socket *so;
+sorecvoob(struct socket *so)
 {
 	struct tcpcb *tp = sototcpcb(so);
 
@@ -297,8 +290,7 @@ sorecvoob(so)
  * There's a lot duplicated code here, but...
  */
 int
-sosendoob(so)
-	struct socket *so;
+sosendoob(struct socket *so)
 {
 	struct sbuf *sb = &so->so_rcv;
 	char buff[2048]; /* XXX Shouldn't be sending more oob data than this */
@@ -356,8 +348,7 @@ sosendoob(so)
  * updating all sbuf field as necessary
  */
 int
-sowrite(so)
-	struct socket *so;
+sowrite(struct socket *so)
 {
 	int  n,nn;
 	struct sbuf *sb = &so->so_rcv;
@@ -451,8 +442,7 @@ sowrite(so)
  * recvfrom() a UDP socket
  */
 void
-sorecvfrom(so)
-	struct socket *so;
+sorecvfrom(struct socket *so)
 {
 	struct sockaddr_in addr;
 	socklen_t addrlen = sizeof(struct sockaddr_in);
@@ -479,7 +469,7 @@ sorecvfrom(so)
 	    icmp_error(so->so_m, ICMP_UNREACH,code, 0,strerror(errno));
 	  } else {
 	    icmp_reflect(so->so_m);
-	    so->so_m = 0; /* Don't m_free() it again! */
+            so->so_m = NULL; /* Don't m_free() it again! */
 	  }
 	  /* No need for this socket anymore, udp_detach it */
 	  udp_detach(so);
@@ -551,9 +541,7 @@ sorecvfrom(so)
  * sendto() a socket
  */
 int
-sosendto(so, m)
-	struct socket *so;
-	struct mbuf *m;
+sosendto(struct socket *so, struct mbuf *m)
 {
 	int ret;
 	struct sockaddr_in addr;
@@ -600,11 +588,7 @@ sosendto(so, m)
  * XXX This should really be tcp_listen
  */
 struct socket *
-solisten(port, laddr, lport, flags)
-	u_int port;
-	u_int32_t laddr;
-	u_int lport;
-	int flags;
+solisten(u_int port, u_int32_t laddr, u_int lport, int flags)
 {
 	struct sockaddr_in addr;
 	struct socket *so;
@@ -706,8 +690,7 @@ sowwakeup(so)
  * times each when only 1 was needed
  */
 void
-soisfconnecting(so)
-	register struct socket *so;
+soisfconnecting(struct socket *so)
 {
 	so->so_state &= ~(SS_NOFDREF|SS_ISFCONNECTED|SS_FCANTRCVMORE|
 			  SS_FCANTSENDMORE|SS_FWDRAIN);
@@ -715,8 +698,7 @@ soisfconnecting(so)
 }
 
 void
-soisfconnected(so)
-        register struct socket *so;
+soisfconnected(struct socket *so)
 {
 	so->so_state &= ~(SS_ISFCONNECTING|SS_FWDRAIN|SS_NOFDREF);
 	so->so_state |= SS_ISFCONNECTED; /* Clobber other states */
@@ -758,8 +740,7 @@ sofcantsendmore(struct socket *so)
 }
 
 void
-soisfdisconnected(so)
-	struct socket *so;
+soisfdisconnected(struct socket *so)
 {
 /*	so->so_state &= ~(SS_ISFCONNECTING|SS_ISFCONNECTED); */
 /*	close(so->s); */
@@ -774,8 +755,7 @@ soisfdisconnected(so)
  * Set CANTSENDMORE once all data has been write()n
  */
 void
-sofwdrain(so)
-	struct socket *so;
+sofwdrain(struct socket *so)
 {
 	if (so->so_rcv.sb_cc)
 		so->so_state |= SS_FWDRAIN;
diff --git a/slirp/tcp_input.c b/slirp/tcp_input.c
index d7805b5307..effedfc966 100644
--- a/slirp/tcp_input.c
+++ b/slirp/tcp_input.c
@@ -121,10 +121,10 @@ tcp_reass(register struct tcpcb *tp, register struct tcpiphdr *ti,
 	int flags;
 
 	/*
-	 * Call with ti==0 after become established to
+	 * Call with ti==NULL after become established to
 	 * force pre-ESTABLISHED data up to user socket.
 	 */
-	if (ti == 0)
+        if (ti == NULL)
 		goto present;
 
 	/*
@@ -230,19 +230,16 @@ present:
  * protocol specification dated September, 1981 very closely.
  */
 void
-tcp_input(m, iphlen, inso)
-	register struct mbuf *m;
-	int iphlen;
-	struct socket *inso;
+tcp_input(struct mbuf *m, int iphlen, struct socket *inso)
 {
   	struct ip save_ip, *ip;
 	register struct tcpiphdr *ti;
 	caddr_t optp = NULL;
 	int optlen = 0;
 	int len, tlen, off;
-	register struct tcpcb *tp = 0;
+        register struct tcpcb *tp = NULL;
 	register int tiflags;
-	struct socket *so = 0;
+        struct socket *so = NULL;
 	int todrop, acked, ourfinisacked, needoutput = 0;
 /*	int dropsocket = 0; */
 	int iss = 0;
@@ -264,7 +261,7 @@ tcp_input(m, iphlen, inso)
 		/* Re-set a few variables */
 		tp = sototcpcb(so);
 		m = so->so_m;
-		so->so_m = 0;
+                so->so_m = NULL;
 		ti = so->so_ti;
 		tiwin = ti->ti_win;
 		tiflags = ti->ti_flags;
@@ -298,8 +295,8 @@ tcp_input(m, iphlen, inso)
 	 * Checksum extended TCP header and data.
 	 */
 	tlen = ((struct ip *)ti)->ip_len;
-	tcpiphdr2qlink(ti)->next = tcpiphdr2qlink(ti)->prev = 0;
-    memset(&ti->ti_i.ih_mbuf, 0 , sizeof(struct mbuf_ptr));
+        tcpiphdr2qlink(ti)->next = tcpiphdr2qlink(ti)->prev = NULL;
+        memset(&ti->ti_i.ih_mbuf, 0 , sizeof(struct mbuf_ptr));
 	ti->ti_x1 = 0;
 	ti->ti_len = htons((u_int16_t)tlen);
 	len = sizeof(struct ip ) + tlen;
@@ -399,7 +396,7 @@ findso:
 	 * the only flag set, then create a session, mark it
 	 * as if it was LISTENING, and continue...
 	 */
-	if (so == 0) {
+        if (so == NULL) {
 	  if ((tiflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) != TH_SYN)
 	    goto dropwithreset;
 
@@ -439,7 +436,7 @@ findso:
 	tp = sototcpcb(so);
 
 	/* XXX Should never fail */
-	if (tp == 0)
+        if (tp == NULL)
 		goto dropwithreset;
 	if (tp->t_state == TCPS_CLOSED)
 		goto drop;
@@ -1697,9 +1694,7 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt)
  */
 
 int
-tcp_mss(tp, offer)
-        register struct tcpcb *tp;
-        u_int offer;
+tcp_mss(struct tcpcb *tp, u_int offer)
 {
 	struct socket *so = tp->t_socket;
 	int mss;
diff --git a/slirp/tcp_output.c b/slirp/tcp_output.c
index 4a7bdbceea..9ed50f5002 100644
--- a/slirp/tcp_output.c
+++ b/slirp/tcp_output.c
@@ -64,8 +64,7 @@ static const u_char  tcp_outflags[TCP_NSTATES] = {
  * Tcp output routine: figure out what should be sent and send it.
  */
 int
-tcp_output(tp)
-	register struct tcpcb *tp;
+tcp_output(struct tcpcb *tp)
 {
 	register struct socket *so = tp->t_socket;
 	register long len, win;
@@ -582,8 +581,7 @@ out:
 }
 
 void
-tcp_setpersist(tp)
-	register struct tcpcb *tp;
+tcp_setpersist(struct tcpcb *tp)
 {
     int t = ((tp->t_srtt >> 2) + tp->t_rttvar) >> 1;
 
diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c
index b30dffdc67..b70f06e062 100644
--- a/slirp/tcp_subr.c
+++ b/slirp/tcp_subr.c
@@ -49,7 +49,7 @@
  * Tcp initialization
  */
 void
-tcp_init()
+tcp_init(void)
 {
 	tcp_iss = 1;		/* wrong */
 	tcb.so_next = tcb.so_prev = &tcb;
@@ -63,8 +63,7 @@ tcp_init()
  */
 /* struct tcpiphdr * */
 void
-tcp_template(tp)
-	struct tcpcb *tp;
+tcp_template(struct tcpcb *tp)
 {
 	struct socket *so = tp->t_socket;
 	register struct tcpiphdr *n = &tp->t_template;
@@ -102,12 +101,8 @@ tcp_template(tp)
  * segment are as specified by the parameters.
  */
 void
-tcp_respond(tp, ti, m, ack, seq, flags)
-	struct tcpcb *tp;
-	register struct tcpiphdr *ti;
-	register struct mbuf *m;
-	tcp_seq ack, seq;
-	int flags;
+tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
+            tcp_seq ack, tcp_seq seq, int flags)
 {
 	register int tlen;
 	int win = 0;
@@ -122,7 +117,7 @@ tcp_respond(tp, ti, m, ack, seq, flags)
 
 	if (tp)
 		win = sbspace(&tp->t_socket->so_rcv);
-	if (m == 0) {
+        if (m == NULL) {
 		if ((m = m_get()) == NULL)
 			return;
 #ifdef TCP_COMPAT_42
@@ -152,7 +147,7 @@ tcp_respond(tp, ti, m, ack, seq, flags)
 	tlen += sizeof (struct tcpiphdr);
 	m->m_len = tlen;
 
-	ti->ti_mbuf = 0;
+        ti->ti_mbuf = NULL;
 	ti->ti_x1 = 0;
 	ti->ti_seq = htonl(seq);
 	ti->ti_ack = htonl(ack);
@@ -182,8 +177,7 @@ tcp_respond(tp, ti, m, ack, seq, flags)
  * protocol control block.
  */
 struct tcpcb *
-tcp_newtcpcb(so)
-	struct socket *so;
+tcp_newtcpcb(struct socket *so)
 {
 	register struct tcpcb *tp;
 
@@ -257,8 +251,7 @@ struct tcpcb *tcp_drop(struct tcpcb *tp, int err)
  *	wake up any sleepers
  */
 struct tcpcb *
-tcp_close(tp)
-	register struct tcpcb *tp;
+tcp_close(struct tcpcb *tp)
 {
 	register struct tcpiphdr *t;
 	struct socket *so = tp->t_socket;
@@ -281,7 +274,7 @@ tcp_close(tp)
  */
 /*	free(tp, M_PCB);  */
 	free(tp);
-	so->so_tcpcb = 0;
+        so->so_tcpcb = NULL;
 	soisfdisconnected(so);
 	/* clobber input socket cache if we're closing the cached connection */
 	if (so == tcp_last_so)
@@ -333,8 +326,7 @@ tcp_quench(i, errno)
  * We can let the user exit from the close as soon as the FIN is acked.
  */
 void
-tcp_sockclosed(tp)
-	struct tcpcb *tp;
+tcp_sockclosed(struct tcpcb *tp)
 {
 
 	DEBUG_CALL("tcp_sockclosed");
@@ -375,8 +367,7 @@ tcp_sockclosed(tp)
  * nonblocking.  Connect returns after the SYN is sent, and does
  * not wait for ACK+SYN.
  */
-int tcp_fconnect(so)
-     struct socket *so;
+int tcp_fconnect(struct socket *so)
 {
   int ret=0;
 
@@ -438,8 +429,7 @@ int tcp_fconnect(so)
  * here and SYN the local-host.
  */
 void
-tcp_connect(inso)
-	struct socket *inso;
+tcp_connect(struct socket *inso)
 {
 	struct socket *so;
 	struct sockaddr_in addr;
@@ -525,8 +515,7 @@ tcp_connect(inso)
  * Attach a TCPCB to a socket.
  */
 int
-tcp_attach(so)
-	struct socket *so;
+tcp_attach(struct socket *so)
 {
 	if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL)
 	   return -1;
@@ -558,14 +547,13 @@ static const struct tos_t tcptos[] = {
 #ifdef CONFIG_QEMU
 static
 #endif
-struct emu_t *tcpemu = 0;
+struct emu_t *tcpemu = NULL;
 
 /*
  * Return TOS according to the above table
  */
 u_int8_t
-tcp_tos(so)
-	struct socket *so;
+tcp_tos(struct socket *so)
 {
 	int i = 0;
 	struct emu_t *emup;
@@ -620,9 +608,7 @@ int do_echo = -1;
  * NOTE: if you return 0 you MUST m_free() the mbuf!
  */
 int
-tcp_emu(so, m)
-	struct socket *so;
-	struct mbuf *m;
+tcp_emu(struct socket *so, struct mbuf *m)
 {
 	u_int n1, n2, n3, n4, n5, n6;
         char buff[257];
@@ -976,7 +962,7 @@ do_prompt:
 		}
 #endif
         case EMU_FTP: /* ftp */
-		*(m->m_data+m->m_len) = 0; /* NULL terminate for strstr */
+                *(m->m_data+m->m_len) = 0; /* NUL terminate for strstr */
 		if ((bptr = (char *)strstr(m->m_data, "ORT")) != NULL) {
 			/*
 			 * Need to emulate the PORT command
@@ -1244,8 +1230,7 @@ do_prompt:
  * return 2 if this is a command-line connection
  */
 int
-tcp_ctl(so)
-	struct socket *so;
+tcp_ctl(struct socket *so)
 {
 	struct sbuf *sb = &so->so_snd;
 	int command;