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-rw-r--r--src/port/rand.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/src/port/rand.c b/src/port/rand.c
new file mode 100644
index 0000000000..faeec88b28
--- /dev/null
+++ b/src/port/rand.c
@@ -0,0 +1,78 @@
+/*-------------------------------------------------------------------------
+ *
+ * rand.c
+ * Missing rand implementations for Win32
+ *
+ *-------------------------------------------------------------------------
+ */
+
+/*
+ * Copyright (c) 1993 Martin Birgmeier
+ * All rights reserved.
+ *
+ * You may redistribute unmodified or modified versions of this source
+ * code provided that the above copyright notice and this and the
+ * following conditions are retained.
+ *
+ * This software is provided ``as is'', and comes with no warranties
+ * of any kind. I shall in no event be liable for anything that happens
+ * to anyone/anything when using this software.
+ */
+#define RAND48_SEED_0 (0x330e)
+#define RAND48_SEED_1 (0xabcd)
+#define RAND48_SEED_2 (0x1234)
+#define RAND48_MULT_0 (0xe66d)
+#define RAND48_MULT_1 (0xdeec)
+#define RAND48_MULT_2 (0x0005)
+#define RAND48_ADD (0x000b)
+
+unsigned short _rand48_seed[3] = {
+ RAND48_SEED_0,
+ RAND48_SEED_1,
+ RAND48_SEED_2
+};
+unsigned short _rand48_mult[3] = {
+ RAND48_MULT_0,
+ RAND48_MULT_1,
+ RAND48_MULT_2
+};
+unsigned short _rand48_add = RAND48_ADD;
+
+void
+_dorand48(unsigned short xseed[3])
+{
+ unsigned long accu;
+ unsigned short temp[2];
+
+ accu = (unsigned long) _rand48_mult[0] * (unsigned long) xseed[0] +
+ (unsigned long) _rand48_add;
+ temp[0] = (unsigned short) accu; /* lower 16 bits */
+ accu >>= sizeof(unsigned short) * 8;
+ accu += (unsigned long) _rand48_mult[0] * (unsigned long) xseed[1] +
+ (unsigned long) _rand48_mult[1] * (unsigned long) xseed[0];
+ temp[1] = (unsigned short) accu; /* middle 16 bits */
+ accu >>= sizeof(unsigned short) * 8;
+ accu += _rand48_mult[0] * xseed[2] + _rand48_mult[1] * xseed[1] + _rand48_mult[2] * xseed[0];
+ xseed[0] = temp[0];
+ xseed[1] = temp[1];
+ xseed[2] = (unsigned short) accu;
+}
+
+long
+lrand48(void)
+{
+ _dorand48(_rand48_seed);
+ return ((long) _rand48_seed[2] << 15) + ((long) _rand48_seed[1] >1);
+}
+
+void
+srand48(long seed)
+{
+ _rand48_seed[0] = RAND48_SEED_0;
+ _rand48_seed[1] = (unsigned short) seed;
+ _rand48_seed[2] = (unsigned short) (seed >16);
+ _rand48_mult[0] = RAND48_MULT_0;
+ _rand48_mult[1] = RAND48_MULT_1;
+ _rand48_mult[2] = RAND48_MULT_2;
+ _rand48_add = RAND48_ADD;
+}