slirp: Use internal state in interface

This now also exports the internal state to the slirp users in qemu,
returning it from slirp_init and expecting it along with service
invocations. Additionally provide an opaque value interface for the
callbacks from slirp into the qemu core.

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

5 files changed, 44 insertions, 43 deletions

diff --git a/if.c b/if.c
index 060c425..660ee84 100644
--- a/if.c
+++ b/if.c
@@ -157,7 +157,7 @@ void if_start(Slirp *slirp)
 
 again:
     /* check if we can really output */
-    if (!slirp_can_output())
+    if (!slirp_can_output(slirp->opaque))
         return;
 
     /*
diff --git a/libslirp.h b/libslirp.h
index 147ae95..955d55c 100644
--- a/libslirp.h
+++ b/libslirp.h
@@ -8,11 +8,11 @@
 struct Slirp;
 typedef struct Slirp Slirp;
 
-void slirp_init(int restricted, struct in_addr vnetwork,
-                struct in_addr vnetmask, struct in_addr vhost,
-                const char *vhostname, const char *tftp_path,
-                const char *bootfile, struct in_addr vdhcp_start,
-                struct in_addr vnameserver);
+Slirp *slirp_init(int restricted, struct in_addr vnetwork,
+                  struct in_addr vnetmask, struct in_addr vhost,
+                  const char *vhostname, const char *tftp_path,
+                  const char *bootfile, struct in_addr vdhcp_start,
+                  struct in_addr vnameserver, void *opaque);
 
 void slirp_select_fill(int *pnfds, fd_set *readfds, fd_set *writefds,
                        fd_set *xfds);
@@ -20,23 +20,25 @@ void slirp_select_fill(int *pnfds, fd_set *readfds, fd_set *writefds,
 void slirp_select_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds,
                        int select_error);
 
-void slirp_input(const uint8_t *pkt, int pkt_len);
+void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len);
 
 /* you must provide the following functions: */
-int slirp_can_output(void);
-void slirp_output(const uint8_t *pkt, int pkt_len);
+int slirp_can_output(void *opaque);
+void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len);
 
-int slirp_add_hostfwd(int is_udp, struct in_addr host_addr, int host_port,
-                      struct in_addr guest_addr, int guest_port);
-int slirp_remove_hostfwd(int is_udp, struct in_addr host_addr, int host_port);
-int slirp_add_exec(int do_pty, const void *args, struct in_addr guest_addr,
-                   int guest_port);
+int slirp_add_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
+                      int host_port, struct in_addr guest_addr, int guest_port);
+int slirp_remove_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
+                         int host_port);
+int slirp_add_exec(Slirp *slirp, int do_pty, const void *args,
+                   struct in_addr guest_addr, int guest_port);
 
-void slirp_connection_info(Monitor *mon);
+void slirp_connection_info(Slirp *slirp, Monitor *mon);
 
-void slirp_socket_recv(struct in_addr guest_addr, int guest_port,
+void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr, int guest_port,
                        const uint8_t *buf, int size);
-size_t slirp_socket_can_recv(struct in_addr guest_addr, int guest_port);
+size_t slirp_socket_can_recv(Slirp *slirp, struct in_addr guest_addr,
+                             int guest_port);
 
 #else /* !CONFIG_SLIRP */
 
diff --git a/misc.c b/misc.c
index 7a94bac..8f2c48d 100644
--- a/misc.c
+++ b/misc.c
@@ -359,7 +359,7 @@ void fd_block(int fd)
 #endif
 }
 
-void slirp_connection_info(Monitor *mon)
+void slirp_connection_info(Slirp *slirp, Monitor *mon)
 {
     const char *const tcpstates[] = {
         [TCPS_CLOSED] = "CLOSED",           [TCPS_LISTEN] = "LISTEN",
@@ -369,7 +369,6 @@ void slirp_connection_info(Monitor *mon)
         [TCPS_LAST_ACK] = "LAST_ACK",       [TCPS_FIN_WAIT_2] = "FIN_WAIT_2",
         [TCPS_TIME_WAIT] = "TIME_WAIT",
     };
-    Slirp *slirp = &slirp_instance;
     struct in_addr dst_addr;
     struct sockaddr_in src;
     socklen_t src_len;
diff --git a/slirp.c b/slirp.c
index 176de4f..ed7e0a3 100644
--- a/slirp.c
+++ b/slirp.c
@@ -187,11 +187,11 @@ static void slirp_init_once(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 restricted, struct in_addr vnetwork,
-                struct in_addr vnetmask, struct in_addr vhost,
-                const char *vhostname, const char *tftp_path,
-                const char *bootfile, struct in_addr vdhcp_start,
-                struct in_addr vnameserver)
+Slirp *slirp_init(int restricted, struct in_addr vnetwork,
+                  struct in_addr vnetmask, struct in_addr vhost,
+                  const char *vhostname, const char *tftp_path,
+                  const char *bootfile, struct in_addr vdhcp_start,
+                  struct in_addr vnameserver, void *opaque)
 {
     Slirp *slirp = &slirp_instance;
 
@@ -226,7 +226,11 @@ void slirp_init(int restricted, struct in_addr vnetwork,
     slirp->vdhcp_startaddr = vdhcp_start;
     slirp->vnameserver_addr = vnameserver;
 
+    slirp->opaque = opaque;
+
     register_savevm("slirp", 0, 2, slirp_state_save, slirp_state_load, slirp);
+
+    return slirp;
 }
 
 #define CONN_CANFSEND(so) \
@@ -633,7 +637,7 @@ static void arp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
             rah->ar_sip = ah->ar_tip;
             memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN);
             rah->ar_tip = ah->ar_sip;
-            slirp_output(arp_reply, sizeof(arp_reply));
+            slirp_output(slirp->opaque, arp_reply, sizeof(arp_reply));
         }
         break;
     case ARPOP_REPLY:
@@ -648,9 +652,8 @@ static void arp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
     }
 }
 
-void slirp_input(const uint8_t *pkt, int pkt_len)
+void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
 {
-    Slirp *slirp = &slirp_instance;
     struct mbuf *m;
     int proto;
 
@@ -722,7 +725,7 @@ void if_encap(Slirp *slirp, const uint8_t *ip_data, int ip_data_len)
         /* target IP */
         rah->ar_tip = iph->ip_dst.s_addr;
         slirp->client_ipaddr = iph->ip_dst;
-        slirp_output(arp_req, sizeof(arp_req));
+        slirp_output(slirp->opaque, arp_req, sizeof(arp_req));
     } else {
         memcpy(eh->h_dest, slirp->client_ethaddr, ETH_ALEN);
         memcpy(eh->h_source, special_ethaddr, ETH_ALEN - 4);
@@ -730,14 +733,14 @@ void if_encap(Slirp *slirp, const uint8_t *ip_data, int ip_data_len)
         memcpy(&eh->h_source[2], &slirp->vhost_addr, 4);
         eh->h_proto = htons(ETH_P_IP);
         memcpy(buf + sizeof(struct ethhdr), ip_data, ip_data_len);
-        slirp_output(buf, ip_data_len + ETH_HLEN);
+        slirp_output(slirp->opaque, buf, ip_data_len + ETH_HLEN);
     }
 }
 
 /* Drop host forwarding rule, return 0 if found. */
-int slirp_remove_hostfwd(int is_udp, struct in_addr host_addr, int host_port)
+int slirp_remove_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
+                         int host_port)
 {
-    Slirp *slirp = &slirp_instance;
     struct socket *so;
     struct socket *head = (is_udp ? &slirp->udb : &slirp->tcb);
     struct sockaddr_in addr;
@@ -758,11 +761,9 @@ int slirp_remove_hostfwd(int is_udp, struct in_addr host_addr, int host_port)
     return -1;
 }
 
-int slirp_add_hostfwd(int is_udp, struct in_addr host_addr, int host_port,
-                      struct in_addr guest_addr, int guest_port)
+int slirp_add_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
+                      int host_port, struct in_addr guest_addr, int guest_port)
 {
-    Slirp *slirp = &slirp_instance;
-
     if (!guest_addr.s_addr) {
         guest_addr = slirp->vdhcp_startaddr;
     }
@@ -778,11 +779,9 @@ int slirp_add_hostfwd(int is_udp, struct in_addr host_addr, int host_port,
     return 0;
 }
 
-int slirp_add_exec(int do_pty, const void *args, struct in_addr guest_addr,
-                   int guest_port)
+int slirp_add_exec(Slirp *slirp, int do_pty, const void *args,
+                   struct in_addr guest_addr, int guest_port)
 {
-    Slirp *slirp = &slirp_instance;
-
     if (!guest_addr.s_addr) {
         guest_addr.s_addr = slirp->vnetwork_addr.s_addr |
                             (htonl(0x0204) & ~slirp->vnetwork_mask.s_addr);
@@ -821,9 +820,9 @@ slirp_find_ctl_socket(Slirp *slirp, struct in_addr guest_addr, int guest_port)
     return NULL;
 }
 
-size_t slirp_socket_can_recv(struct in_addr guest_addr, int guest_port)
+size_t slirp_socket_can_recv(Slirp *slirp, struct in_addr guest_addr,
+                             int guest_port)
 {
-    Slirp *slirp = &slirp_instance;
     struct iovec iov[2];
     struct socket *so;
 
@@ -838,10 +837,9 @@ size_t slirp_socket_can_recv(struct in_addr guest_addr, int guest_port)
     return sopreprbuf(so, iov, NULL);
 }
 
-void slirp_socket_recv(struct in_addr guest_addr, int guest_port,
+void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr, int guest_port,
                        const uint8_t *buf, int size)
 {
-    Slirp *slirp = &slirp_instance;
     int ret;
     struct socket *so = slirp_find_ctl_socket(slirp, guest_addr, guest_port);
 
diff --git a/slirp.h b/slirp.h
index 0cf525d..5cb13aa 100644
--- a/slirp.h
+++ b/slirp.h
@@ -255,6 +255,8 @@ struct Slirp {
     /* tftp states */
     char *tftp_prefix;
     struct tftp_session tftp_sessions[TFTP_SESSIONS_MAX];
+
+    void *opaque;
 };
 
 extern Slirp slirp_instance;