/* isIn:
* Return 1 if object objp is in subgraph gp.
*/
int isIn(Agraph_t * gp, Agobj_t * objp)
{
if (!sameG(gp, objp, "isIn", 0))
return 0;
switch (AGTYPE(objp)) {
case AGRAPH:
return (agparent((Agraph_t *) objp) == gp);
case AGNODE:
return (agidnode(gp, AGID(objp), 0) != 0);
default:
return (agsubedge(gp, (Agedge_t *) objp, 0) != 0);
}
}
static void cc_dfs(Agraph_t* g, Agraph_t * comp, Agnode_t * n)
{
Agedge_t *e;
Agnode_t *other;
CCMARK(n);
agidnode(comp, AGID(n), 1);
for (e = agfstedge(g, n); e; e = agnxtedge(g, e, n)) {
if (agtail(e) == n)
other = aghead(e);
else
other = agtail(e);
if (!CCMARKED(other))
cc_dfs(g, comp, other);
}
}
/* compOf:
* Return connected component of node.
*/
Agraph_t *compOf(Agraph_t * g, Agnode_t * n)
{
Agraph_t *cg;
Agnode_t *np;
static int id;
char name[64];
if (!(n = agidnode(g, AGID(n), 0)))
return 0; /* n not in g */
for (np = agfstnode(g); np; np = agnxtnode(g, np))
CCUNMARK(np);
sprintf(name, "_cc_%d", id++);
cg = openSubg(g, name);
cc_dfs(g, cg, n);
return cg;
}
