puzzles: resync with upstream

This brings the puzzles source to upstream commit e2135d5. (I've made my own
changes on top of that.)

This brings in a couple bugfixes and a new solver for Dominosa.

Change-Id: I11d46b43171787832330a5e2e0d2f353f36f727d

1 files changed, 26 insertions, 0 deletions

diff --git a/apps/plugins/puzzles/src/puzzles.h b/apps/plugins/puzzles/src/puzzles.h
index 48d3d83b6e..1732abe3e9 100644
--- a/apps/plugins/puzzles/src/puzzles.h
+++ b/apps/plugins/puzzles/src/puzzles.h
@@ -595,6 +595,32 @@ bool findloop_run(struct findloopstate *state, int nvertices,
 bool findloop_is_loop_edge(struct findloopstate *state, int u, int v);
 
 /*
+ * Alternative query function, which returns true if the u-v edge is a
+ * _bridge_, i.e. a non-loop edge, i.e. an edge whose removal would
+ * disconnect a currently connected component of the graph.
+ *
+ * If the return value is true, then the numbers of vertices that
+ * would be in the new components containing u and v are written into
+ * u_vertices and v_vertices respectively.
+ */
+bool findloop_is_bridge(
+    struct findloopstate *pv, int u, int v, int *u_vertices, int *v_vertices);
+
+/*
+ * Helper function to sort an array. Differs from standard qsort in
+ * that it takes a context parameter that is passed to the compare
+ * function.
+ *
+ * I wrap it in a macro so that you only need to give the element
+ * count of the array. The element size is determined by sizeof.
+ */
+typedef int (*arraysort_cmpfn_t)(const void *av, const void *bv, void *ctx);
+void arraysort_fn(void *array, size_t nmemb, size_t size,
+                  arraysort_cmpfn_t cmp, void *ctx);
+#define arraysort(array, nmemb, cmp, ctx) \
+    arraysort_fn(array, nmemb, sizeof(*(array)), cmp, ctx)
+
+/*
  * Data structure containing the function calls and data specific
  * to a particular game. This is enclosed in a data structure so
  * that a particular platform can choose, if it wishes, to compile