Initial import of qemu-2.4.1HEADmaster

1 files changed, 41 insertions, 0 deletions

diff --git a/roms/ipxe/src/core/random.c b/roms/ipxe/src/core/random.c
new file mode 100644
index 00000000..8824dca3
--- /dev/null
+++ b/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;
+}