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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/core/random.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/core/random.c')
-rw-r--r--qemu/roms/ipxe/src/core/random.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/core/random.c b/qemu/roms/ipxe/src/core/random.c
new file mode 100644
index 000000000..8824dca3a
--- /dev/null
+++ b/qemu/roms/ipxe/src/core/random.c
@@ -0,0 +1,41 @@
+/** @file
+ *
+ * Random number generation
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdlib.h>
+#include <ipxe/timer.h>
+
+static int32_t rnd_seed = 0;
+
+/**
+ * Seed the pseudo-random number generator
+ *
+ * @v seed Seed value
+ */
+void srandom ( unsigned int seed ) {
+ rnd_seed = seed;
+}
+
+/**
+ * Generate a pseudo-random number between 0 and 2147483647L or 2147483562?
+ *
+ * @ret rand Pseudo-random number
+ */
+long int random ( void ) {
+ int32_t q;
+
+ if ( ! rnd_seed ) /* Initialize linear congruential generator */
+ srandom ( currticks() );
+
+ /* simplified version of the LCG given in Bruce Schneier's
+ "Applied Cryptography" */
+ q = ( rnd_seed / 53668 );
+ rnd_seed = ( 40014 * ( rnd_seed - 53668 * q ) - 12211 * q );
+ if ( rnd_seed < 0 )
+ rnd_seed += 2147483563L;
+ return rnd_seed;
+}