diff options
Diffstat (limited to 'src/ipcpd/normal/pol/graph.c')
-rw-r--r-- | src/ipcpd/normal/pol/graph.c | 263 |
1 files changed, 142 insertions, 121 deletions
diff --git a/src/ipcpd/normal/pol/graph.c b/src/ipcpd/normal/pol/graph.c index 9901fbaa..9e723737 100644 --- a/src/ipcpd/normal/pol/graph.c +++ b/src/ipcpd/normal/pol/graph.c @@ -40,12 +40,14 @@ struct edge { struct list_head next; struct vertex * nb; qosspec_t qs; + int announced; }; struct vertex { struct list_head next; uint64_t addr; struct list_head edges; + int index; }; struct graph { @@ -93,6 +95,7 @@ static struct edge * add_edge(struct vertex * vertex, list_head_init(&edge->next); edge->nb = nb; + edge->announced = 0; list_add(&edge->next, &vertex->edges); @@ -110,6 +113,7 @@ static struct vertex * add_vertex(struct graph * graph, { struct vertex * vertex; struct list_head * p; + int i = 0; vertex = malloc(sizeof(*vertex)); if (vertex == NULL) @@ -119,14 +123,25 @@ static struct vertex * add_vertex(struct graph * graph, list_head_init(&vertex->edges); vertex->addr = addr; + /* Keep them ordered on address. */ list_for_each(p, &graph->vertices) { struct vertex * v = list_entry(p, struct vertex, next); if (v->addr > addr) break; + i++; } + vertex->index = i; + list_add_tail(&vertex->next, p); + /* Increase the index of the vertices to the right. */ + list_for_each(p, &graph->vertices) { + struct vertex * v = list_entry(p, struct vertex, next); + if (v->addr > addr) + v->index++; + } + graph->nr_vertices++; return vertex; @@ -140,6 +155,13 @@ static void del_vertex(struct graph * graph, list_del(&vertex->next); + /* Decrease the index of the vertices to the right. */ + list_for_each(p, &graph->vertices) { + struct vertex * v = list_entry(p, struct vertex, next); + if (v->addr > vertex->addr) + v->index--; + } + list_for_each_safe(p, n, &vertex->edges) { struct edge * e = list_entry(p, struct edge, next); del_edge(e); @@ -231,7 +253,7 @@ int graph_update_edge(struct graph * graph, e = add_edge(v, nb); if (e == NULL) { if (list_is_empty(&v->edges)) - del_vertex(graph, v); + del_vertex(graph, v); if (list_is_empty(&nb->edges)) del_vertex(graph, nb); pthread_mutex_unlock(&graph->lock); @@ -240,13 +262,15 @@ int graph_update_edge(struct graph * graph, } } + e->announced++; e->qs = qs; nb_e = find_edge_by_addr(nb, s_addr); if (nb_e == NULL) { nb_e = add_edge(nb, v); if (nb_e == NULL) { - del_edge(e); + if (--e->announced == 0) + del_edge(e); if (list_is_empty(&v->edges)) del_vertex(graph, v); if (list_is_empty(&nb->edges)) @@ -257,6 +281,7 @@ int graph_update_edge(struct graph * graph, } } + nb_e->announced++; nb_e->qs = qs; pthread_mutex_unlock(&graph->lock); @@ -280,33 +305,35 @@ int graph_del_edge(struct graph * graph, v = find_vertex_by_addr(graph, s_addr); if (v == NULL) { pthread_mutex_unlock(&graph->lock); - log_err("No such vertex."); + log_err("No such source vertex."); return -1; } nb = find_vertex_by_addr(graph, d_addr); if (nb == NULL) { pthread_mutex_unlock(&graph->lock); - log_err("No such vertex."); + log_err("No such destination vertex."); return -1; } e = find_edge_by_addr(v, d_addr); if (e == NULL) { pthread_mutex_unlock(&graph->lock); - log_err("No such edge."); + log_err("No such source edge."); return -1; } nb_e = find_edge_by_addr(nb, s_addr); if (nb_e == NULL) { pthread_mutex_unlock(&graph->lock); - log_err("No such edge."); + log_err("No such destination edge."); return -1; } - del_edge(e); - del_edge(nb_e); + if (--e->announced == 0) + del_edge(e); + if (--nb_e->announced == 0) + del_edge(nb_e); /* Removing vertex if it was the last edge */ if (list_is_empty(&v->edges)) @@ -319,106 +346,76 @@ int graph_del_edge(struct graph * graph, return 0; } -static int get_min_vertex(struct vertex ** vertices, - int nr_vertices, +static int get_min_vertex(struct graph * graph, int * dist, + bool * used, struct vertex ** v) { - int min = INT_MAX; - int index = -1; - int i; + int min = INT_MAX; + int index = -1; + int i = 0; + struct list_head * p = NULL; *v = NULL; - for (i = 0; i < nr_vertices; i++) { - if (vertices[i] == NULL) + list_for_each(p, &graph->vertices) { + if (used[i] == true) { + i++; continue; + } if (dist[i] < min) { - *v = vertices[i]; min = dist[i]; index = i; + *v = list_entry(p, struct vertex, next); } + + i++; } if (index != -1) - vertices[index] = NULL; + used[index] = true; return index; } -static int get_vertex_number(struct vertex ** vertices, - int nr_vertices, - struct vertex * v) - -{ - int i; - - for (i = 0; i < nr_vertices; i++) { - if (vertices[i] == v) - return i; - } - - return -1; -} - -static int get_vertex_index(struct graph * graph, - struct vertex * v) - -{ - struct list_head * p = NULL; - struct vertex * vertex; - int i = 0; - - list_for_each(p, &graph->vertices) { - vertex = list_entry(p, struct vertex, next); - if (vertex == v) - return i; - i++; - } - - return -1; -} - static struct vertex ** dijkstra(struct graph * graph, uint64_t src) { int dist[graph->nr_vertices]; - struct vertex * vertices[graph->nr_vertices]; + bool used[graph->nr_vertices]; struct list_head * p = NULL; int i = 0; - int j = 0; struct vertex * v = NULL; struct edge * e = NULL; int alt; - struct vertex ** prev; + struct vertex ** nhop; - prev = malloc(sizeof(*prev) * graph->nr_vertices); - if (prev == NULL) + nhop = malloc(sizeof(*nhop) * graph->nr_vertices); + if (nhop == NULL) return NULL; /* Init the data structures */ list_for_each(p, &graph->vertices) { v = list_entry(p, struct vertex, next); - vertices[i] = v; if (v->addr == src) dist[i] = 0; else dist[i] = INT_MAX; - prev[i] = NULL; + + nhop[i] = NULL; + used[i] = false; i++; } /* Perform actual Dijkstra */ - i = get_min_vertex(vertices, graph->nr_vertices, dist, &v); + i = get_min_vertex(graph, dist, used, &v); while (v != NULL) { list_for_each(p, &v->edges) { e = list_entry(p, struct edge, next); - j = get_vertex_number(vertices, - graph->nr_vertices, - e->nb); - if (j == -1) + /* Only include it if both sides announced it. */ + if (e->announced != 2) continue; /* @@ -427,93 +424,117 @@ static struct vertex ** dijkstra(struct graph * graph, * weight for a different QoS cube. */ alt = dist[i] + 1; - if (alt < dist[j]) { - dist[j] = alt; - prev[j] = v; + if (alt < dist[e->nb->index]) { + dist[e->nb->index] = alt; + if (v->addr == src) + nhop[e->nb->index] = e->nb; + else + nhop[e->nb->index] = nhop[i]; } } - i = get_min_vertex(vertices, graph->nr_vertices, dist, &v); + i = get_min_vertex(graph, dist, used, &v); } - return prev; + return nhop; } -ssize_t graph_routing_table(struct graph * graph, - uint64_t s_addr, - struct routing_table *** table) +static void free_routing_table(struct list_head * table) { - struct vertex ** prevs; - struct list_head * p = NULL; - int i = 0; - int index = 0; - int j = 0; - int k = 0; - struct vertex * prev; - struct vertex * nhop; - struct vertex * v; + struct list_head * h; + struct list_head * p; + struct list_head * q; + struct list_head * i; + + list_for_each_safe(p, h, table) { + struct routing_table * t = + list_entry(p, struct routing_table, next); + list_for_each_safe(q, i, &t->nhops) { + struct nhop * n = + list_entry(q, struct nhop, next); + list_del(&n->next); + free(n); + } + list_del(&t->next); + free(t); + } +} + +void graph_free_routing_table(struct graph * graph, + struct list_head * table) +{ + assert(table); + + pthread_mutex_lock(&graph->lock); + + free_routing_table(table); + + pthread_mutex_unlock(&graph->lock); +} + +int graph_routing_table(struct graph * graph, + uint64_t s_addr, + struct list_head * table) +{ + struct vertex ** nhops; + struct list_head * p; + int i = 0; + struct vertex * v; + struct routing_table * t; + struct nhop * n; pthread_mutex_lock(&graph->lock); /* We need at least 2 vertices for a table */ - if (graph->nr_vertices < 2) { - pthread_mutex_unlock(&graph->lock); - return -1; - } + if (graph->nr_vertices < 2) + goto fail_vertices; - prevs = dijkstra(graph, s_addr); - if (prevs == NULL) { - pthread_mutex_unlock(&graph->lock); - return -1; - } + nhops = dijkstra(graph, s_addr); + if (nhops == NULL) + goto fail_vertices; - *table = malloc(sizeof(**table) * (graph->nr_vertices - 1)); - if (*table == NULL) { - pthread_mutex_unlock(&graph->lock); - free(prevs); - return -1; - } + list_head_init(table); - /* - * Now loop through the list of predecessors - * to construct the routing table - */ + /* Now construct the routing table from the nhops. */ list_for_each(p, &graph->vertices) { v = list_entry(p, struct vertex, next); - prev = prevs[i]; - nhop = v; /* This is the src */ - if (prev == NULL) { + if (nhops[i] == NULL) { i++; continue; } - index = get_vertex_index(graph, prev); - while (prevs[index] != NULL) { - nhop = prev; - prev = prevs[index]; - index = get_vertex_index(graph, prev); - } + t = malloc(sizeof(*t)); + if (t == NULL) + goto fail_t; - (*table)[j] = malloc(sizeof(***table)); - if ((*table)[j] == NULL) { - pthread_mutex_unlock(&graph->lock); - for (k = 0; k < j; ++k) - free((*table)[k]); - free(*table); - free(prevs); - return -1; - } + list_head_init(&t->nhops); + + n = malloc(sizeof(*n)); + if (n == NULL) + goto fail_n; + + t->dst = v->addr; + n->nhop = nhops[i]->addr; + + list_add(&n->next, &t->nhops); + list_add(&t->next, table); - (*table)[j]->dst = v->addr; - (*table)[j]->nhop = nhop->addr; - j++; i++; } pthread_mutex_unlock(&graph->lock); - free(prevs); + free(nhops); - return j; + return 0; + + fail_n: + free(t); + fail_t: + free_routing_table(table); + free(nhops); + fail_vertices: + pthread_mutex_unlock(&graph->lock); + return -1; } |