slirp: Factor out internal state structure

The essence of this patch is to stuff (almost) all global variables of
the slirp stack into the structure Slirp. In this step, we still keep
the structure as global variable, directly accessible by the whole
stack. Changes to the external interface of slirp will be applied in
the following patches.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 41 insertions, 39 deletions

diff --git a/slirp/ip_input.c b/slirp/ip_input.c
index b07d3d5..35230f8 100644
--- a/slirp/ip_input.c
+++ b/slirp/ip_input.c
@@ -42,11 +42,8 @@
 #include <osdep.h>
 #include "ip_icmp.h"
 
-struct ipq ipq;
-
-static struct ip *ip_reass(register struct ip *ip,
-                           register struct ipq *fp);
-static void ip_freef(struct ipq *fp);
+static struct ip *ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp);
+static void ip_freef(Slirp *slirp, struct ipq *fp);
 static void ip_enq(register struct ipasfrag *p,
                    register struct ipasfrag *prev);
 static void ip_deq(register struct ipasfrag *p);
@@ -56,11 +53,11 @@ static void ip_deq(register struct ipasfrag *p);
  * All protocols not implemented in kernel go to raw IP protocol handler.
  */
 void
-ip_init(void)
+ip_init(Slirp *slirp)
 {
-	ipq.ip_link.next = ipq.ip_link.prev = &ipq.ip_link;
-	udp_init();
-	tcp_init();
+    slirp->ipq.ip_link.next = slirp->ipq.ip_link.prev = &slirp->ipq.ip_link;
+    udp_init(slirp);
+    tcp_init(slirp);
 }
 
 /*
@@ -70,6 +67,7 @@ ip_init(void)
 void
 ip_input(struct mbuf *m)
 {
+	Slirp *slirp = m->slirp;
 	register struct ip *ip;
 	int hlen;
 
@@ -120,19 +118,19 @@ ip_input(struct mbuf *m)
 		goto bad;
 	}
 
-    if (slirp_restrict) {
-        if ((ip->ip_dst.s_addr & vnetwork_mask.s_addr) ==
-            vnetwork_addr.s_addr) {
+    if (slirp->restricted) {
+        if ((ip->ip_dst.s_addr & slirp->vnetwork_mask.s_addr) ==
+            slirp->vnetwork_addr.s_addr) {
             if (ip->ip_dst.s_addr == 0xffffffff && ip->ip_p != IPPROTO_UDP)
                 goto bad;
         } else {
+            uint32_t inv_mask = ~slirp->vnetwork_mask.s_addr;
             struct ex_list *ex_ptr;
 
-            if ((ip->ip_dst.s_addr & ~vnetwork_mask.s_addr) ==
-                ~vnetwork_mask.s_addr)
+            if ((ip->ip_dst.s_addr & inv_mask) == inv_mask) {
                 goto bad;
-
-            for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next)
+            }
+            for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next)
                 if (ex_ptr->ex_addr.s_addr == ip->ip_dst.s_addr)
                     break;
 
@@ -167,7 +165,8 @@ ip_input(struct mbuf *m)
 		 * Look for queue of fragments
 		 * of this datagram.
 		 */
-		for (l = ipq.ip_link.next; l != &ipq.ip_link; l = l->next) {
+		for (l = slirp->ipq.ip_link.next; l != &slirp->ipq.ip_link;
+		     l = l->next) {
             fp = container_of(l, struct ipq, ip_link);
             if (ip->ip_id == fp->ipq_id &&
                     ip->ip_src.s_addr == fp->ipq_src.s_addr &&
@@ -197,13 +196,13 @@ ip_input(struct mbuf *m)
 		 * attempt reassembly; if it succeeds, proceed.
 		 */
 		if (ip->ip_tos & 1 || ip->ip_off) {
-			ip = ip_reass(ip, fp);
+			ip = ip_reass(slirp, ip, fp);
                         if (ip == NULL)
 				return;
-			m = dtom(ip);
+			m = dtom(slirp, ip);
 		} else
 			if (fp)
-		   	   ip_freef(fp);
+		   	   ip_freef(slirp, fp);
 
 	} else
 		ip->ip_len -= hlen;
@@ -239,9 +238,9 @@ bad:
  * is given as fp; otherwise have to make a chain.
  */
 static struct ip *
-ip_reass(register struct ip *ip, register struct ipq *fp)
+ip_reass(Slirp *slirp, struct ip *ip, struct ipq *fp)
 {
-	register struct mbuf *m = dtom(ip);
+	register struct mbuf *m = dtom(slirp, ip);
 	register struct ipasfrag *q;
 	int hlen = ip->ip_hl << 2;
 	int i, next;
@@ -263,10 +262,13 @@ ip_reass(register struct ip *ip, register struct ipq *fp)
 	 * If first fragment to arrive, create a reassembly queue.
 	 */
         if (fp == NULL) {
-	  struct mbuf *t;
-	  if ((t = m_get()) == NULL) goto dropfrag;
+	  struct mbuf *t = m_get(slirp);
+
+	  if (t == NULL) {
+	      goto dropfrag;
+	  }
 	  fp = mtod(t, struct ipq *);
-	  insque(&fp->ip_link, &ipq.ip_link);
+	  insque(&fp->ip_link, &slirp->ipq.ip_link);
 	  fp->ipq_ttl = IPFRAGTTL;
 	  fp->ipq_p = ip->ip_p;
 	  fp->ipq_id = ip->ip_id;
@@ -296,7 +298,7 @@ ip_reass(register struct ip *ip, register struct ipq *fp)
 		if (i > 0) {
 			if (i >= ip->ip_len)
 				goto dropfrag;
-			m_adj(dtom(ip), i);
+			m_adj(dtom(slirp, ip), i);
 			ip->ip_off += i;
 			ip->ip_len -= i;
 		}
@@ -312,11 +314,11 @@ ip_reass(register struct ip *ip, register struct ipq *fp)
 		if (i < q->ipf_len) {
 			q->ipf_len -= i;
 			q->ipf_off += i;
-			m_adj(dtom(q), i);
+			m_adj(dtom(slirp, q), i);
 			break;
 		}
 		q = q->ipf_next;
-		m_freem(dtom(q->ipf_prev));
+		m_freem(dtom(slirp, q->ipf_prev));
 		ip_deq(q->ipf_prev);
 	}
 
@@ -340,11 +342,11 @@ insert:
 	 * Reassembly is complete; concatenate fragments.
 	 */
     q = fp->frag_link.next;
-	m = dtom(q);
+	m = dtom(slirp, q);
 
 	q = (struct ipasfrag *) q->ipf_next;
 	while (q != (struct ipasfrag*)&fp->frag_link) {
-	  struct mbuf *t = dtom(q);
+	  struct mbuf *t = dtom(slirp, q);
 	  q = (struct ipasfrag *) q->ipf_next;
 	  m_cat(m, t);
 	}
@@ -375,7 +377,7 @@ insert:
 	ip->ip_src = fp->ipq_src;
 	ip->ip_dst = fp->ipq_dst;
 	remque(&fp->ip_link);
-	(void) m_free(dtom(fp));
+	(void) m_free(dtom(slirp, fp));
 	m->m_len += (ip->ip_hl << 2);
 	m->m_data -= (ip->ip_hl << 2);
 
@@ -391,17 +393,17 @@ dropfrag:
  * associated datagrams.
  */
 static void
-ip_freef(struct ipq *fp)
+ip_freef(Slirp *slirp, struct ipq *fp)
 {
 	register struct ipasfrag *q, *p;
 
 	for (q = fp->frag_link.next; q != (struct ipasfrag*)&fp->frag_link; q = p) {
 		p = q->ipf_next;
 		ip_deq(q);
-		m_freem(dtom(q));
+		m_freem(dtom(slirp, q));
 	}
 	remque(&fp->ip_link);
-	(void) m_free(dtom(fp));
+	(void) m_free(dtom(slirp, fp));
 }
 
 /*
@@ -435,24 +437,24 @@ ip_deq(register struct ipasfrag *p)
  * queue, discard it.
  */
 void
-ip_slowtimo(void)
+ip_slowtimo(Slirp *slirp)
 {
     struct qlink *l;
 
 	DEBUG_CALL("ip_slowtimo");
 
-    l = ipq.ip_link.next;
+    l = slirp->ipq.ip_link.next;
 
         if (l == NULL)
 	   return;
 
-	while (l != &ipq.ip_link) {
+    while (l != &slirp->ipq.ip_link) {
         struct ipq *fp = container_of(l, struct ipq, ip_link);
         l = l->next;
 		if (--fp->ipq_ttl == 0) {
-			ip_freef(fp);
+			ip_freef(slirp, fp);
 		}
-	}
+    }
 }
 
 /*