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-rw-r--r--src/lib/util/coreutil.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/src/lib/util/coreutil.c b/src/lib/util/coreutil.c
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+++ b/src/lib/util/coreutil.c
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+/***************************************************************************
+
+ coreutil.c
+
+ Miscellaneous utility code
+
+ Copyright (c) 1996-2007, Nicola Salmoria and the MAME Team.
+ Visit http://mamedev.org for licensing and usage restrictions.
+
+****************************************************************************/
+
+#include "coreutil.h"
+
+
+/***************************************************************************
+ BINARY CODED DECIMAL HELPERS
+***************************************************************************/
+
+int bcd_adjust(int value)
+{
+ if ((value & 0xf) >= 0xa)
+ value = value + 0x10 - 0xa;
+ if ((value & 0xf0) >= 0xa0)
+ value = value - 0xa0 + 0x100;
+ return value;
+}
+
+
+UINT32 dec_2_bcd(UINT32 a)
+{
+ UINT32 result = 0;
+ int shift = 0;
+
+ while (a != 0)
+ {
+ result |= (a % 10) << shift;
+ a /= 10;
+ shift += 4;
+ }
+ return result;
+}
+
+
+UINT32 bcd_2_dec(UINT32 a)
+{
+ UINT32 result = 0;
+ UINT32 scale = 1;
+
+ while (a != 0)
+ {
+ result += (a & 0x0f) * scale;
+ a >>= 4;
+ scale *= 10;
+ }
+ return result;
+}
+
+
+
+/***************************************************************************
+ GREGORIAN CALENDAR HELPERS
+***************************************************************************/
+
+int gregorian_is_leap_year(int year)
+{
+ return !(year % 100 ? year % 4 : year % 400);
+}
+
+
+/* months are one counted */
+int gregorian_days_in_month(int month, int year)
+{
+ if (month == 2)
+ return gregorian_is_leap_year(year) ? 29 : 28;
+ else if (month == 4 || month == 6 || month == 9 || month == 11)
+ return 30;
+ else
+ return 31;
+}
+
+
+/***************************************************************************
+ MISC
+***************************************************************************/
+
+void rand_memory(void *memory, size_t length)
+{
+ UINT8 *bytes = (UINT8 *) memory;
+ UINT32 currand;
+ size_t i;
+
+ currand = rand();
+ currand <<= 15;
+ currand ^= rand();
+
+ for (i = 0; i < length; i++)
+ {
+ currand = currand * 214013 + 2531011;
+ bytes[i] = (UINT8) (currand >> 16);
+ }
+}
+