This patch adds a new test graph "shortcut2" which includes a negative cost
edge. Along with that we add a testcase for Dijkstra's algorithm checking
that it gracefully fails in this case.
Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
---
ccan/aga/test/api-adjacency.c | 6 ++-
ccan/aga/test/api-dijkstra.c | 15 ++++++-
ccan/aga/test/shortcut2.c | 94 ++++++++++++++++++++++++++++++++++++++++++
ccan/aga/test/simple-graph.h | 21 ++++++++++
ccan/agar/test/api-adjacency.c | 6 ++-
ccan/agar/test/api-dijkstra.c | 16 ++++++-
ccan/agar/test/shortcut2.c | 87 ++++++++++++++++++++++++++++++++++++++
ccan/agar/test/simple-graphr.h | 21 ++++++++++
8 files changed, 262 insertions(+), 4 deletions(-)
create mode 100644 ccan/aga/test/shortcut2.c
create mode 100644 ccan/agar/test/shortcut2.c
diff --git a/ccan/aga/test/api-adjacency.c b/ccan/aga/test/api-adjacency.c
index 8f6c6d5..6e50430 100644
--- a/ccan/aga/test/api-adjacency.c
+++ b/ccan/aga/test/api-adjacency.c
@@ -62,8 +62,9 @@ int main(void)
struct error_graph eg;
struct traversal1_graph t1g;
struct shortcut1_graph s1g;
+ struct shortcut2_graph s2g;
- plan_tests(2 + 7 + 35 + 30 + 30 + 42 + 9 + 30 + 9);
+ plan_tests(2 + 7 + 35 + 30 + 30 + 42 + 9 + 30 + 9 + 9);
trivial_graph_init(&tg);
test_adjacency("trivial", &tg.sg, trivial_adjacency);
@@ -95,5 +96,8 @@ int main(void)
shortcut1_graph_init(&s1g);
test_adjacency("shortcut1 graph", &s1g.sg, shortcut1_adjacency);
+ shortcut2_graph_init(&s2g);
+ test_adjacency("shortcut2 graph", &s2g.sg, shortcut2_adjacency);
+
return exit_status();
}
diff --git a/ccan/aga/test/api-dijkstra.c b/ccan/aga/test/api-dijkstra.c
index 9b94c98..f9b8d76 100644
--- a/ccan/aga/test/api-dijkstra.c
+++ b/ccan/aga/test/api-dijkstra.c
@@ -234,12 +234,24 @@ static void test_shortcut1(void)
aga_finish(&s1g.sg.g);
}
+static void test_shortcut2(void)
+{
+ struct shortcut2_graph s2g;
+
+ shortcut2_graph_init(&s2g);
+
+ ok1(aga_dijkstra_start(&s2g.sg.g, &s2g.sg.nodes[1]) == 0);
+ aga_dijkstra_all_paths(&s2g.sg.g);
+ ok1(aga_error(&s2g.sg.g) == AGA_ERR_NEGATIVE_COST);
+ aga_finish(&s2g.sg.g);
+}
+
int main(void)
{
plan_tests(7 + 20
+ FULL_LEN * (1 + FULL_LEN*4)
+ CHAIN_LEN * (1 + CHAIN_LEN*2)
- + 12 + 32 + 7);
+ + 12 + 32 + 7 + 2);
test_trivial();
test_parallel();
@@ -248,6 +260,7 @@ int main(void)
test_error();
test_traversal1();
test_shortcut1();
+ test_shortcut2();
return exit_status();
}
diff --git a/ccan/aga/test/shortcut2.c b/ccan/aga/test/shortcut2.c
new file mode 100644
index 0000000..33eee0a
--- /dev/null
+++ b/ccan/aga/test/shortcut2.c
@@ -0,0 +1,94 @@
+#include "config.h"
+
+#include <assert.h>
+
+#include <ccan/container_of/container_of.h>
+#include <ccan/ptrint/ptrint.h>
+
+#include <ccan/aga/aga.h>
+
+#include "simple-graph.h"
+
+static ptrint_t *shortcut2_first_edge(const struct aga_graph *g,
+ const struct aga_node *n)
+{
+ struct shortcut2_graph *s1g = container_of(g, struct shortcut2_graph,
+ sg.g);
+ int ni = n - s1g->sg.nodes;
+
+ switch (ni) {
+ case 1:
+ case 2:
+ return int2ptr(1);
+
+ case 3:
+ return NULL;
+
+ default:
+ assert(0);
+ }
+}
+
+static ptrint_t *shortcut2_next_edge(const struct aga_graph *g,
+ const struct aga_node *n,
+ ptrint_t *e)
+{
+ struct shortcut2_graph *s1g = container_of(g, struct shortcut2_graph,
+ sg.g);
+ int ni = n - s1g->sg.nodes;
+ int index = ptr2int(e);
+
+ switch (ni) {
+ case 1:
+ if (index == 1)
+ return int2ptr(2);
+ assert(index == 2);
+ return NULL;
+
+ case 2:
+ assert(index == 1);
+ return NULL;
+
+ default:
+ assert(0);
+ }
+}
+
+static int shortcut2_edge_info(const struct aga_graph *g,
+ const struct aga_node *n,
+ ptrint_t *e, struct aga_edge_info *ei)
+{
+ struct shortcut2_graph *s1g = container_of(g, struct shortcut2_graph,
+ sg.g);
+ int ni = n - s1g->sg.nodes;
+ int index = ptr2int(e);
+
+ switch (ni) {
+ case 1:
+ if (index == 1) {
+ ei->to = &s1g->sg.nodes[3];
+ } else {
+ assert(index == 2);
+ ei->to = &s1g->sg.nodes[2];
+ }
+ ei->icost = 2;
+ break;
+
+ case 2:
+ assert(index == 1);
+ ei->to = &s1g->sg.nodes[3];
+ ei->icost = -1;
+ break;
+
+ default:
+ assert(0);
+ }
+ return 0;
+}
+
+void shortcut2_graph_init(struct shortcut2_graph *s1g)
+{
+ simple_graph_init(&s1g->sg, shortcut2_first_edge,
+ shortcut2_next_edge,
+ shortcut2_edge_info);
+}
diff --git a/ccan/aga/test/simple-graph.h b/ccan/aga/test/simple-graph.h
index 77ba2a6..b8da3ad 100644
--- a/ccan/aga/test/simple-graph.h
+++ b/ccan/aga/test/simple-graph.h
@@ -235,4 +235,25 @@ static const struct adjacency_list shortcut1_adjacency[] =
{
{},
};
+/* Shortcut-2 graph
+ *
+ * A ---- (2) -----> C
+ * \ /
+ * (2)-> B --(-1)
+ *
+ * This provides an example of a graph with a negative edge cost, but
+ * no negative cost cycles (and so still with well defined shortest
+ * paths).
+ */
+struct shortcut2_graph {
+ struct simple_graph sg;
+};
+void shortcut2_graph_init(struct shortcut2_graph *s2g);
+static const struct adjacency_list shortcut2_adjacency[] = {
+ {1, {3, 2}},
+ {2, {3}},
+ {3, {}},
+ {},
+};
+
#endif /* _TEST_GRAPHS_H */
diff --git a/ccan/agar/test/api-adjacency.c b/ccan/agar/test/api-adjacency.c
index 9482bba..2b2637d 100644
--- a/ccan/agar/test/api-adjacency.c
+++ b/ccan/agar/test/api-adjacency.c
@@ -56,8 +56,9 @@ int main(void)
struct grid_graphr ggr1, ggr2;
struct error_graphr egr;
struct shortcut1_graphr s1gr;
+ struct shortcut2_graphr s2gr;
- plan_tests(1 + 5 + 30 + 22 + 21 + 33 + 6 + 6);
+ plan_tests(1 + 5 + 30 + 22 + 21 + 33 + 6 + 6 + 6);
trivial_graphr_init(&tgr);
test_adjacency("trivial", &tgr.gr, trivial_adjacencyr);
@@ -86,5 +87,8 @@ int main(void)
shortcut1_graphr_init(&s1gr);
test_adjacency("shortcut1 graph", &s1gr.gr, shortcut1_adjacencyr);
+ shortcut2_graphr_init(&s2gr);
+ test_adjacency("shortcut2 graph", &s2gr.gr, shortcut2_adjacencyr);
+
return exit_status();
}
diff --git a/ccan/agar/test/api-dijkstra.c b/ccan/agar/test/api-dijkstra.c
index 3ade158..1321e26 100644
--- a/ccan/agar/test/api-dijkstra.c
+++ b/ccan/agar/test/api-dijkstra.c
@@ -238,12 +238,25 @@ static void test_shortcut1(void)
tal_free(sr);
}
+static void test_shortcut2(void)
+{
+ struct shortcut2_graphr s2gr;
+ struct agar_state *sr;
+
+ shortcut2_graphr_init(&s2gr);
+
+ ok1(sr = agar_dijkstra_new(NULL, &s2gr.gr, int2ptr(1)));
+ agar_dijkstra_all_paths(sr);
+ ok1(agar_error(sr) == AGA_ERR_NEGATIVE_COST);
+ tal_free(sr);
+}
+
int main(void)
{
plan_tests(6 + 23
+ FULL_LEN * (FULL_LEN*4 - 1)
+ CHAIN_LEN * (1 + CHAIN_LEN*2)
- + 12 + 32 + 7);
+ + 12 + 32 + 7 + 2);
test_trivial();
test_parallel();
@@ -252,6 +265,7 @@ int main(void)
test_error();
test_traversal1();
test_shortcut1();
+ test_shortcut2();
return exit_status();
}
diff --git a/ccan/agar/test/shortcut2.c b/ccan/agar/test/shortcut2.c
new file mode 100644
index 0000000..aff89a6
--- /dev/null
+++ b/ccan/agar/test/shortcut2.c
@@ -0,0 +1,87 @@
+#include "config.h"
+
+#include <assert.h>
+
+#include <ccan/container_of/container_of.h>
+#include <ccan/ptrint/ptrint.h>
+
+#include <ccan/agar/agar.h>
+
+#include "simple-graphr.h"
+
+static const void *shortcut2_first_edge_r(const struct agar_graph *gr,
+ const void *nr)
+{
+ int ni = ptr2int(nr);
+
+ switch (ni) {
+ case 1:
+ case 2:
+ return int2ptr(1);
+
+ case 3:
+ return NULL;
+
+ default:
+ assert(0);
+ }
+}
+
+static const void *shortcut2_next_edge_r(const struct agar_graph *gr,
+ const void *nr, const void *e)
+{
+ int ni = ptr2int(nr);
+ int index = ptr2int(e);
+
+ switch (ni) {
+ case 1:
+ if (index == 1)
+ return int2ptr(2);
+ assert(index == 2);
+ return NULL;
+
+ case 2:
+ assert(index == 1);
+ return NULL;
+
+ default:
+ assert(0);
+ }
+}
+
+static int shortcut2_edge_info_r(const struct agar_graph *gr,
+ const void *nr, const void *e,
+ struct agar_edge_info *eir)
+{
+ int ni = ptr2int(nr);
+ int index = ptr2int(e);
+
+ switch (ni) {
+ case 1:
+ if (index == 1) {
+ eir->to = int2ptr(3);
+ } else {
+ assert(index == 2);
+ eir->to = int2ptr(2);
+ }
+ eir->icost = 2;
+ break;
+
+ case 2:
+ assert(index == 1);
+ eir->to = int2ptr(3);
+ eir->icost = -1;
+ break;
+
+ default:
+ assert(0);
+ }
+ return 0;
+}
+
+void shortcut2_graphr_init(struct shortcut2_graphr *s1gr)
+{
+ agar_init_graph(&s1gr->gr, shortcut2_first_edge_r,
+ shortcut2_next_edge_r,
+ shortcut2_edge_info_r);
+}
diff --git a/ccan/agar/test/simple-graphr.h b/ccan/agar/test/simple-graphr.h
index 168ee29..2fe98a4 100644
--- a/ccan/agar/test/simple-graphr.h
+++ b/ccan/agar/test/simple-graphr.h
@@ -219,4 +219,25 @@ static const struct adjacency_listr shortcut1_adjacencyr[]
= {
{},
};
+/* Shortcut-2 graph
+ *
+ * A ---- (2) -----> C
+ * \ /
+ * (2)-> B --(-1)
+ *
+ * This provides an example of a graph with a negative edge cost, but
+ * no negative cost cycles (and so still with well defined shortest
+ * paths).
+ */
+struct shortcut2_graphr {
+ struct agar_graph gr;
+};
+void shortcut2_graphr_init(struct shortcut2_graphr *s2gr);
+static const struct adjacency_listr shortcut2_adjacencyr[] = {
+ {1, {3, 2}},
+ {2, {3}},
+ {3, {}},
+ {},
+};
+
#endif /* _SIMPLE_GRAPHR_H */
--
2.5.0
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