1 files changed, 137 insertions, 0 deletions
diff --git a/3rdparty/openpgm-svn-r1085/pgm/rand.c b/3rdparty/openpgm-svn-r1085/pgm/rand.c
new file mode 100644
index 0000000..91b71eb
--- /dev/null
+++ b/3rdparty/openpgm-svn-r1085/pgm/rand.c
@@ -0,0 +1,137 @@
+/* vim:ts=8:sts=8:sw=4:noai:noexpandtab
+ *
+ * portable weak pseudo-random generator.
+ *
+ * Copyright (c) 2010 Miru Limited.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _WIN32
+#	include <errno.h>
+#	include <stdio.h>
+#endif
+#include <impl/framework.h>
+
+
+//#define RAND_DEBUG
+
+
+/* locals */
+
+static pgm_rand_t		global_rand = { .seed = 0 };
+static volatile uint32_t	rand_ref_count = 0;
+static pgm_mutex_t		rand_mutex;
+
+
+void
+pgm_rand_init (void)
+{
+	if (pgm_atomic_exchange_and_add32 (&rand_ref_count, 1) > 0)
+		return;
+
+	pgm_mutex_init (&rand_mutex);
+}
+
+void
+pgm_rand_shutdown (void)
+{
+	pgm_return_if_fail (pgm_atomic_read32 (&rand_ref_count) > 0);
+
+	if (pgm_atomic_exchange_and_add32 (&rand_ref_count, (uint32_t)-1) != 1)
+		return;
+
+	pgm_mutex_free (&rand_mutex);
+}
+
+void
+pgm_rand_create (
+	pgm_rand_t*	new_rand
+	)
+{
+/* pre-conditions */
+	pgm_assert (NULL != new_rand);
+
+#ifndef _WIN32
+/* attempt to read seed from kernel
+ */
+	FILE* fp;
+	do {
+		fp = fopen ("/dev/urandom", "rb");
+	} while (PGM_UNLIKELY(EINTR == errno));
+	if (fp) {
+		size_t items_read;
+		do {
+			items_read = fread (&new_rand->seed, sizeof(new_rand->seed), 1, fp);
+		} while (PGM_UNLIKELY(EINTR == errno));
+		fclose (fp);
+		if (1 == items_read)
+			return;
+	}
+#endif /* !_WIN32 */
+	const pgm_time_t now = pgm_time_update_now();
+	new_rand->seed = (uint32_t)pgm_to_msecs (now);
+}
+
+/* derived from POSIX.1-2001 example implementation of rand()
+ */
+
+uint32_t
+pgm_rand_int (
+	pgm_rand_t*	r
+	)
+{
+/* pre-conditions */
+	pgm_assert (NULL != r);
+
+	r->seed = r->seed * 1103515245 + 12345;
+	return r->seed;
+}
+
+int32_t
+pgm_rand_int_range (
+	pgm_rand_t*	r,
+	int32_t		begin,
+	int32_t		end
+	)
+{
+/* pre-conditions */
+	pgm_assert (NULL != r);
+
+	return begin + pgm_rand_int (r) % (end - begin);
+}
+
+uint32_t
+pgm_random_int (void)
+{
+	pgm_mutex_lock (&rand_mutex);
+	if (PGM_UNLIKELY(!global_rand.seed))
+		pgm_rand_create (&global_rand);
+	const uint32_t rand_value = pgm_rand_int (&global_rand);
+	pgm_mutex_unlock (&rand_mutex);
+	return rand_value;
+}
+
+int32_t
+pgm_random_int_range (
+	int32_t		begin,
+	int32_t		end
+	)
+{
+	const uint32_t rand_value = pgm_random_int();
+	return begin + rand_value % (end - begin);
+}
+
+/* eof */