Use a linked list for neighbours.

babel.c

@@ -910,8 +910,6 @@ dump_tables(FILE *out)
     fprintf(out, "My id %s seqno %d\n", format_address(myid), myseqno);
 
     FOR_ALL_NEIGHBOURS(neigh) {
-        if(!neighbour_valid(neigh))
-            continue;
         fprintf(out, "Neighbour %s ", format_address(neigh->id));
         fprintf(out, "at %s dev %s reach %04x rxcost %d txcost %d%s.\n",
                 format_address(neigh->address),

babel.h

@@ -21,7 +21,6 @@ THE SOFTWARE.
 */
 
 #define MAXSRCS 256
-#define MAXNEIGHBOURS 64
 
 #define INFINITY ((unsigned short)(~0))
 

message.c

@@ -1022,8 +1022,6 @@ send_ihu(struct neighbour *neigh, struct network *net)
     if(neigh == NULL) {
         struct neighbour *ngh;
         FOR_ALL_NEIGHBOURS(ngh) {
-            if(!neighbour_valid(ngh))
-                continue;
             if(ngh->network == net)
                 send_ihu(ngh, net);
         }
@@ -1056,7 +1054,7 @@ send_marginal_ihu(struct network *net)
 {
     struct neighbour *neigh;
     FOR_ALL_NEIGHBOURS(neigh) {
-        if(!neighbour_valid(neigh) || (net && neigh->network != net))
+        if(net && neigh->network != net)
             continue;
         if(neigh->txcost >= 384 || (neigh->reach & 0xF000) != 0xF000)
             send_ihu(neigh, net);

neighbour.c

@@ -34,13 +34,18 @@ THE SOFTWARE.
 #include "route.h"
 #include "message.h"
 
-struct neighbour neighs[MAXNEIGHBOURS];
-int numneighs = 0;
+struct neighbour *neighs = NULL;
 
-int
-neighbour_valid(struct neighbour *neigh)
+struct neighbour *
+find_neighbour(const unsigned char *address, struct network *net)
 {
-    return neigh->hello_seqno != -2;
+    struct neighbour *neigh;
+    FOR_ALL_NEIGHBOURS(neigh) {
+        if(memcmp(address, neigh->address, 16) == 0 &&
+           neigh->network == net)
+            return neigh;
+    }
+    return NULL;
 }
 
 void
@@ -49,35 +54,23 @@ flush_neighbour(struct neighbour *neigh)
     flush_neighbour_routes(neigh);
     if(unicast_neighbour == neigh)
         flush_unicast(1);
-    memset(neigh, 0, sizeof(*neigh));
-    VALGRIND_MAKE_MEM_UNDEFINED(neigh, sizeof(*neigh));
-    neigh->hello_seqno = -2;
-    while(numneighs > 0 && !neighbour_valid(&neighs[numneighs - 1])) {
-       numneighs--;
-       VALGRIND_MAKE_MEM_UNDEFINED(&neighs[numneighs],
-                                   sizeof(neighs[numneighs]));
-    }
-}
 
-struct neighbour *
-find_neighbour(const unsigned char *address, struct network *net)
-{
-    struct neighbour *neigh;
-    FOR_ALL_NEIGHBOURS(neigh) {
-        if(!neighbour_valid(neigh))
-            continue;
-        if(memcmp(address, neigh->address, 16) == 0 &&
-           neigh->network == net)
-            return neigh;
+    if(neighs == neigh) {
+        neighs = neigh->next;
+    } else {
+        struct neighbour *previous = neighs;
+        while(previous->next != neigh)
+            previous = previous->next;
+        previous->next = neigh->next;
     }
-    return NULL;
+    free(neigh);
 }
 
 struct neighbour *
 add_neighbour(const unsigned char *id, const unsigned char *address,
               struct network *net)
 {
-    struct neighbour *neigh, *ngh;
+    struct neighbour *neigh;
     const struct timeval zero = {0, 0};
 
     neigh = find_neighbour(address, net);
@@ -93,17 +86,13 @@ add_neighbour(const unsigned char *id, const unsigned char *address,
     }
     debugf("Creating neighbour %s (%s).\n",
            format_address(id), format_address(address));
-    FOR_ALL_NEIGHBOURS(ngh) {
-        if(!neighbour_valid(ngh))
-            neigh = ngh;
-    }
-    if(!neigh) {
-        if(numneighs >= MAXNEIGHBOURS) {
-            fprintf(stderr, "Too many neighbours.\n");
-            return NULL;
-        }
-        neigh = &neighs[numneighs++];
+
+    neigh = malloc(sizeof(struct neighbour));
+    if(neigh == NULL) {
+        perror("malloc(neighbour)");
+        return NULL;
     }
+
     neigh->hello_seqno = -1;
     memcpy(neigh->id, id, 16);
     memcpy(neigh->address, address, 16);
@@ -114,6 +103,8 @@ add_neighbour(const unsigned char *id, const unsigned char *address,
     neigh->hello_interval = 0;
     neigh->ihu_interval = 0;
     neigh->network = net;
+    neigh->next = neighs;
+    neighs = neigh;
     send_hello(net);
     return neigh;
 }
@@ -240,16 +231,16 @@ check_neighbours()
 
     debugf("Checking neighbours.\n");
 
-    FOR_ALL_NEIGHBOURS(neigh) {
-        if(!neighbour_valid(neigh))
-            continue;
-
+    neigh = neighs;
+    while(neigh) {
         changed = update_neighbour(neigh, -1, 0);
 
         if(neigh->reach == 0 ||
            neigh->hello_time.tv_sec > now.tv_sec || /* clock stepped */
            timeval_minus_msec(&now, &neigh->hello_time) > 300000) {
-            flush_neighbour(neigh);
+            struct neighbour *old = neigh;
+            neigh = neigh->next;
+            flush_neighbour(old);
             continue;
         }
 
@@ -264,6 +255,7 @@ check_neighbours()
             msecs = MIN(msecs, neigh->hello_interval * 10);
         if(neigh->ihu_interval > 0)
             msecs = MIN(msecs, neigh->ihu_interval * 10);
+        neigh = neigh->next;
     }
 
     return msecs;

neighbour.h

@@ -21,8 +21,8 @@ THE SOFTWARE.
 */
 
 struct neighbour {
-    /* This is -1 when unknown, and -2 for an invalid neighbour,
-       so don't make it unsigned */
+    struct neighbour *next;
+    /* This is -1 when unknown, so don't make it unsigned */
     int hello_seqno;
     unsigned char id[16];
     unsigned char address[16];
@@ -35,11 +35,10 @@ struct neighbour {
     struct network *network;
 };
 
-extern struct neighbour neighs[MAXNEIGHBOURS];
-extern int numneighs;
+extern struct neighbour *neighs;
 
 #define FOR_ALL_NEIGHBOURS(_neigh) \
-    for(_neigh = neighs; _neigh < neighs + numneighs; _neigh++)
+    for(_neigh = neighs; _neigh; _neigh = _neigh->next)
 
 int neighbour_valid(struct neighbour *neigh);
 void flush_neighbour(struct neighbour *neigh);