There is no reason to rename subgraphs within connected component

subgraphs. On the other hand, renaming them causes problems with
compound edges. So, we no longer rename them.
Also, check for nodes residing in disjoint clusters and report them.

diff --git a/cmd/tools/ccomps.c b/cmd/tools/ccomps.c
index 39f80b7d35b0645dc4343185af79bd1c97d9c6c6..d6274821c65d6f7d5feb772ccfad703e1e0bf245 100644 (file)
--- a/cmd/tools/ccomps.c
+++ b/cmd/tools/ccomps.c
@@ -31,7 +31,7 @@
 
 typedef struct {
     Agrec_t h;
-    char cc_subg;
+    char cc_subg;   /* true iff subgraph corresponds to a component */
 } Agraphinfo_t;
 
 typedef struct {
@@ -284,28 +284,22 @@ static char *getBuf(int n)
  * edges in subg. Copy the attributes of subg to g. Return the subgraph.
  * If not, return null.
  */
-static Agraph_t *projectG(Agraph_t * subg, Agraph_t * g, char *pfx,
-                         int pfxlen, int inCluster)
+static Agraph_t *projectG(Agraph_t * subg, Agraph_t * g, int inCluster)
 {
     Agraph_t *proj = 0;
     Agnode_t *n;
     Agnode_t *m;
-    char *name;
 
     for (n = agfstnode(subg); n; n = agnxtnode(subg, n)) {
        if ((m = agfindnode(g, agnameof(n)))) {
            if (proj == 0) {
-               name = getBuf(strlen(agnameof(subg)) + pfxlen + 2);
-               sprintf(name, "%s_%s", agnameof(subg), pfx);
-               proj = agsubg(g, name, 1);
+               proj = agsubg(g, agnameof(subg), 1);
            }
            agsubnode(proj, m, 1);
        }
     }
     if (!proj && inCluster) {
-       name = getBuf(strlen(agnameof(subg)) + pfxlen + 2);
-       sprintf(name, "%s_%s", agnameof(subg), pfx);
-       proj = agsubg(g, name, 1);
+       proj = agsubg(g, agnameof(subg), 1);
     }
     if (proj) {
        nodeInduce(proj, subg);
@@ -320,8 +314,7 @@ static Agraph_t *projectG(Agraph_t * subg, Agraph_t * g, char *pfx,
  * If non-empty, add to subgraph.
  */
 static void
-subgInduce(Agraph_t * root, Agraph_t * g, char *pfx, int pfxlen,
-          int inCluster)
+subgInduce(Agraph_t * root, Agraph_t * g, int inCluster)
 {
     Agraph_t *subg;
     Agraph_t *proj;
@@ -331,9 +324,9 @@ subgInduce(Agraph_t * root, Agraph_t * g, char *pfx, int pfxlen,
     for (subg = agfstsubg(root); subg; subg = agnxtsubg(subg)) {
        if (GD_cc_subg(subg))
            continue;
-       if ((proj = projectG(subg, g, pfx, pfxlen, inCluster))) {
+       if ((proj = projectG(subg, g, inCluster))) {
            in_cluster = inCluster || (useClusters && isCluster(subg));
-           subgInduce(subg, proj, pfx, pfxlen, in_cluster);
+           subgInduce(subg, proj, in_cluster);
        }
     }
 }
@@ -341,25 +334,22 @@ subgInduce(Agraph_t * root, Agraph_t * g, char *pfx, int pfxlen,
 static void
 subGInduce(Agraph_t* g, Agraph_t * out)
 {
-    subgInduce(g, out, agnameof(out), strlen(agnameof(out)), 0);
+    subgInduce(g, out, 0);
 }
 
 #define PFX1 "%s_cc"
 #define PFX2 "%s_cc_%ld"
 
-/* deriveGraph:
- * Create derived graph dg of g where nodes correspond to cluster or
- * top-level nodes and there is an edge in dg if there is an edge in g
- * between any nodes in the respective clusters.
+/* deriveClusters:
+ * Construct nodes in derived graph corresponding top-level clusters.
+ * Since a cluster might be wrapped in a subgraph, we need to traverse
+ * down into the tree of subgraphs
  */
-static Agraph_t *deriveGraph(Agraph_t * g)
+static void deriveClusters(Agraph_t* dg, Agraph_t * g)
 {
-    Agraph_t *dg;
+    Agraph_t *subg;
     Agnode_t *dn;
     Agnode_t *n;
-    Agraph_t *subg;
-
-    dg = agopen("dg", Agstrictundirected, (Agdisc_t *) 0);
 
     for (subg = agfstsubg(g); subg; subg = agnxtsubg(subg)) {
        if (!strncmp(agnameof(subg), "cluster", 7)) {
@@ -367,10 +357,33 @@ static Agraph_t *deriveGraph(Agraph_t * g)
            agbindrec (dn, "nodeinfo", sizeof(Agnodeinfo_t), TRUE);
            ND_ptr(dn) = (Agobj_t*)subg;
            for (n = agfstnode(subg); n; n = agnxtnode(subg, n)) {
+               if (ND_ptr(n)) {
+                  fprintf (stderr, "Error: node \"%s\" belongs to two disjoint clusters \"%s\" and \"%s\"\n",
+                       agnameof (n), agnameof(subg), agnameof(ND_dn(n)));  
+               }
                ND_ptr(n) = (Agobj_t*)dn;
            }
        }
+       else {
+           deriveClusters (dg, subg);
+       }
     }
+}
+
+/* deriveGraph:
+ * Create derived graph dg of g where nodes correspond to top-level nodes 
+ * or clusters, and there is an edge in dg if there is an edge in g
+ * between any nodes in the respective clusters.
+ */
+static Agraph_t *deriveGraph(Agraph_t * g)
+{
+    Agraph_t *dg;
+    Agnode_t *dn;
+    Agnode_t *n;
+
+    dg = agopen("dg", Agstrictundirected, (Agdisc_t *) 0);
+
+    deriveClusters (dg, g);
 
     for (n = agfstnode(g); n; n = agnxtnode(g, n)) {
        if (ND_dn(n))