The Windows RNG turns out to only give about 16 bits at a time. This

is (a) pretty feeble, and (b) means that although Net seeds transfer
between platforms and still generate the same game, there's a
suspicious discrepancy in the typical seed _generated_ by each
platform.
I have a better RNG kicking around in this code base already, so
I'll just use it. Each midend has its own random_state, which it
passes to new_game_seed() as required. A handy consequence of this
is that initial seed data is now passed to midend_new(), which means
that new platform implementors are unlikely to forget to seed the
RNG because failure to do so causes a compile error!

[originally from svn r4187]

1 files changed, 7 insertions, 4 deletions

diff --git a/midend.c b/midend.c
index 818b278..cacd66e 100644
--- a/midend.c
+++ b/midend.c
@@ -13,6 +13,8 @@
 
 struct midend_data {
     frontend *frontend;
+    random_state *random;
+
     char *seed;
     int fresh_seed;
     int nstates, statesize, statepos;
@@ -36,11 +38,12 @@ struct midend_data {
     } \
 } while (0)
 
-midend_data *midend_new(frontend *frontend)
+midend_data *midend_new(frontend *fe, void *randseed, int randseedsize)
 {
     midend_data *me = snew(midend_data);
 
-    me->frontend = frontend;
+    me->frontend = fe;
+    me->random = random_init(randseed, randseedsize);
     me->nstates = me->statesize = me->statepos = 0;
     me->states = NULL;
     me->params = default_params();
@@ -88,7 +91,7 @@ void midend_new_game(midend_data *me)
 
     if (!me->fresh_seed) {
 	sfree(me->seed);
-	me->seed = new_game_seed(me->params);
+	me->seed = new_game_seed(me->params, me->random);
     } else
 	me->fresh_seed = FALSE;
 
@@ -252,7 +255,7 @@ float *midend_colours(midend_data *me, int *ncolours)
     float *ret;
 
     if (me->nstates == 0) {
-        char *seed = new_game_seed(me->params);
+        char *seed = new_game_seed(me->params, me->random);
         state = new_game(me->params, seed);
         sfree(seed);
     } else