igmp.h, igmp.c, netif.h, netif.c, ip.c: To enable to have interfaces with IGMP, and others without it, there is a new NETIF_FLAG_IGMP flag to set in netif->flags if you want IGMP on an interface. igmp_stop() is now called inside netif_remove(). igmp_report_groups() is now called inside netif_set_link_up() (need to have LWIP_NETIF_LINK_CALLBACK=1) to resend reports once the link is up (avoid to wait the next query message to receive the matching multicast streams).

CHANGELOG

@@ -19,6 +19,14 @@ HISTORY
 
   ++ New features:
 
+  2007-09-09 Frédéric Bernon, Bill Florac
+  * igmp.h, igmp.c, netif.h, netif.c, ip.c: To enable to have interfaces with IGMP,
+    and others without it, there is a new NETIF_FLAG_IGMP flag to set in netif->flags
+    if you want IGMP on an interface. igmp_stop() is now called inside netif_remove().
+    igmp_report_groups() is now called inside netif_set_link_up() (need to have
+    LWIP_NETIF_LINK_CALLBACK=1) to resend reports once the link is up (avoid to wait
+    the next query message to receive the matching multicast streams).
+
   2007-09-08 Frédéric Bernon
   * sockets.c, ip.h, api.h, tcp.h: declare a "struct ip_pcb" which only contains
     IP_PCB. Add in the netconn's "pcb" union a "struct ip_pcb *ip;" (no size change).

src/core/ipv4/igmp.c

@@ -117,6 +117,27 @@ igmp_init(void)
   igmp_group_list = NULL;
 }
 
+#ifdef LWIP_DEBUG
+/**
+ * Dump global IGMP groups list
+ */
+void
+igmp_dump_group_list()
+{ 
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_dump_group_list: [%"U32_F"] ", (u32_t)(group->group_state)));
+    ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+    LWIP_DEBUGF(IGMP_DEBUG, (" on if %x\n", (int) group->interface));
+    group = group->next;
+  }
+  LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+}
+#else
+#define igmp_dump_group_list()
+#endif /* LWIP_DEBUG */
+
 /**
  * Start IGMP processing on interface
  *
@@ -149,6 +170,70 @@ igmp_start(struct netif *netif)
   return ERR_MEM;
 }
 
+/**
+ * Stop IGMP processing on interface
+ *
+ * @param netif network interface on which stop IGMP processing
+ */
+err_t
+igmp_stop(struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+  struct igmp_group *prev  = NULL;
+  struct igmp_group *next;
+
+  /* look for groups joined on this interface further down the list */
+  while (group != NULL) {
+    next = group->next;
+    /* is it a group joined on this interface? */
+    if (group->interface == netif) {
+      /* is it the first group of the list? */
+      if (group == igmp_group_list) {
+        igmp_group_list = next;
+      }
+      /* is there a "previous" group defined? */
+      if (prev != NULL) {
+        prev->next = next;
+      }
+      /* disable the group at the MAC level */
+      if (netif->igmp_mac_filter != NULL) {
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
+        ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+        LWIP_DEBUGF(IGMP_DEBUG, (") on if %x\n", (int) netif));
+        netif->igmp_mac_filter(netif, &(group->group_address), IGMP_DEL_MAC_FILTER);
+      }
+      /* free group */
+      memp_free(MEMP_IGMP_GROUP, group);
+    } else {
+      /* change the "previous" */
+      prev = group;
+    }
+    /* move to "next" */
+    group = next;
+  }
+  return ERR_OK;
+}
+
+/**
+ * Report IGMP memberships for this interface
+ *
+ * @param netif network interface on which report IGMP memberships
+ */
+void
+igmp_report_groups( struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %x\n", (int) netif));
+
+  while (group != NULL) {
+    if (group->interface == netif) {
+      igmp_delaying_member( group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+    }
+    group = group->next;
+  }
+}
+
 /**
  * Search for a group in the global igmp_group_list
  *
@@ -162,7 +247,7 @@ igmp_lookfor_group(struct netif *ifp, struct ip_addr *addr)
 {
   struct igmp_group *group = igmp_group_list;
 
-  while (group) {
+  while (group != NULL) {
     if ((group->interface == ifp) && (ip_addr_cmp(&(group->group_address), addr))) {
       return group;
     }
@@ -386,7 +471,7 @@ igmp_joingroup(struct ip_addr *ifaddr, struct ip_addr *groupaddr)
   netif = netif_list;
   while (netif != NULL) {
     /* Should we join this interface ? */
-    if ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr))) {
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
       /* find group or create a new one if not found */
       group = igmp_lookup_group(netif, groupaddr);
 
@@ -456,7 +541,7 @@ igmp_leavegroup(struct ip_addr *ifaddr, struct ip_addr *groupaddr)
   netif = netif_list;
   while (netif != NULL) {
     /* Should we leave this interface ? */
-    if ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr))) {
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
       /* find group */
       group = igmp_lookfor_group(netif, groupaddr);
 

src/core/ipv4/ip.c

@@ -237,7 +237,7 @@ ip_input(struct pbuf *p, struct netif *inp) {
   /* match packet against an interface, i.e. is this packet for us? */
 #if LWIP_IGMP
   if (ip_addr_ismulticast(&(iphdr->dest)))
-   { if (igmp_lookfor_group( inp, &(iphdr->dest)))
+   { if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group( inp, &(iphdr->dest))))
       { netif = inp;
       }
      else

src/core/netif.c

@@ -138,7 +138,9 @@ netif_add(struct netif *netif, struct ip_addr *ipaddr, struct ip_addr *netmask,
 
 #if LWIP_IGMP
   /* start IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
     igmp_start( netif);
+  }
 #endif /* LWIP_IGMP */
 
   LWIP_DEBUGF(NETIF_DEBUG, ("netif: added interface %c%c IP addr ",
@@ -179,6 +181,13 @@ void netif_remove(struct netif * netif)
 {
   if ( netif == NULL ) return;
 
+#if LWIP_IGMP
+  /* stop IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_stop( netif);
+  }
+#endif /* LWIP_IGMP */
+
   snmp_delete_ipaddridx_tree(netif);
 
   /*  is it the first netif? */
@@ -461,6 +470,13 @@ void netif_set_link_up(struct netif *netif )
   }
 #endif /* LWIP_ARP */
 
+#if LWIP_IGMP
+  /* resend IGMP memberships */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_report_groups( netif);
+  }
+#endif /* LWIP_IGMP */
+
   NETIF_LINK_CALLBACK(netif);
 }
 

src/include/ipv4/lwip/igmp.h

@@ -112,6 +112,10 @@ void   igmp_init(void);
 
 err_t  igmp_start( struct netif *netif);
 
+err_t  igmp_stop( struct netif *netif);
+
+void   igmp_report_groups( struct netif *netif);
+
 struct igmp_group *igmp_lookfor_group( struct netif *ifp, struct ip_addr *addr);
 
 struct igmp_group *igmp_lookup_group( struct netif *ifp, struct ip_addr *addr);

src/include/lwip/netif.h

@@ -76,6 +76,8 @@ extern "C" {
 #define NETIF_FLAG_LINK_UP      0x10U
 /** if set, the netif is an device using ARP */
 #define NETIF_FLAG_ETHARP       0x20U
+/** if set, the netif has IGMP capability */
+#define NETIF_FLAG_IGMP         0x40U
 
 /** Generic data structure used for all lwIP network interfaces.
  *  The following fields should be filled in by the initialization