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-rw-r--r--contrib/syslinux-4.02/gpxe/src/core/random.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/core/random.c b/contrib/syslinux-4.02/gpxe/src/core/random.c
new file mode 100644
index 0000000..6e7374e
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/core/random.c
@@ -0,0 +1,41 @@
+/** @file
+ *
+ * Random number generation
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdlib.h>
+#include <gpxe/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;
+}