Imported Upstream version 16.04

[deb_dpdk.git] / lib / librte_eal / common / include / rte_random.h

diff --git a/lib/librte_eal/common/include/rte_random.h b/lib/librte_eal/common/include/rte_random.h
new file mode 100644 (file)
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+++ b/lib/librte_eal/common/include/rte_random.h
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+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RTE_RANDOM_H_
+#define _RTE_RANDOM_H_
+
+/**
+ * @file
+ *
+ * Pseudo-random Generators in RTE
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdlib.h>
+
+/**
+ * Seed the pseudo-random generator.
+ *
+ * The generator is automatically seeded by the EAL init with a timer
+ * value. It may need to be re-seeded by the user with a real random
+ * value.
+ *
+ * @param seedval
+ *   The value of the seed.
+ */
+static inline void
+rte_srand(uint64_t seedval)
+{
+       srand48((long unsigned int)seedval);
+}
+
+/**
+ * Get a pseudo-random value.
+ *
+ * This function generates pseudo-random numbers using the linear
+ * congruential algorithm and 48-bit integer arithmetic, called twice
+ * to generate a 64-bit value.
+ *
+ * @return
+ *   A pseudo-random value between 0 and (1<<64)-1.
+ */
+static inline uint64_t
+rte_rand(void)
+{
+       uint64_t val;
+       val = lrand48();
+       val <<= 32;
+       val += lrand48();
+       return val;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif /* _RTE_PER_LCORE_H_ */