initial commit

1 files changed, 210 insertions, 0 deletions

diff --git a/dfoxtest.c b/dfoxtest.c
new file mode 100644
index 0000000..aefdd5d
--- /dev/null
+++ b/dfoxtest.c
@@ -0,0 +1,210 @@
+/*#include <stdint.h>*/
+typedef char             int8_t;
+typedef unsigned char   uint8_t;
+typedef short           int16_t;
+typedef unsigned short uint16_t;
+typedef long            int32_t;
+typedef unsigned long  uint32_t;
+
+/*#include <stdbool.h>*/
+typedef uint8_t bool;
+#ifndef true
+	#define true 1
+#endif
+#ifndef false
+	#define false 0
+#endif
+
+/*Defines*/
+#define PREFIX_BITS_PER_BYTE 8
+	/*Neither can be greater than 128*/
+#define PREFIX_intsize     4
+#define PREFIX_INTSIZE     8
+
+/*Typedefs*/
+typedef uint8_t PREFIX_INT[PREFIX_INTSIZE];
+typedef int32_t PREFIX_int;
+
+/*Globals*/
+bool PREFIX_math_overflow;
+
+/*==============================================================CODE=============================================================*/
+
+void PREFIX_zero_int(PREFIX_INT *ptr)
+{
+	uint8_t i;
+
+	for (i = 0; i < PREFIX_INTSIZE; i++)
+		*ptr[i] = 0;
+}
+
+bool PREFIX_isneg(PREFIX_INT *in)
+{
+	return (*in[PREFIX_INTSIZE-1] & 0x80) >> 7;
+}
+
+void PREFIX_int_to_buf(PREFIX_INT *dest, PREFIX_int *src)
+{
+	PREFIX_int tmp;
+	uint8_t i;
+
+	tmp = *src;
+	for (i = 0; i < PREFIX_intsize; i++)
+		*dest[i] = (tmp >> (i*PREFIX_BITS_PER_BYTE)) & 0xFF;
+}
+
+void PREFIX_buf_to_int(PREFIX_int *dest, PREFIX_INT *src)
+{
+	PREFIX_int ret;
+	uint8_t i;
+
+	ret = 0;
+	for (i = 0; i < PREFIX_INTSIZE; i++) {
+		ret  += dest[i];
+		ret <<= PREFIX_BITS_PER_BYTE;
+	}
+
+	*src[0] = ret;
+}
+
+void PREFIX_buf_to_buf(PREFIX_INT *dest, PREFIX_INT *src)
+{
+	uint8_t i;
+
+	for (i = 0; i < PREFIX_INTSIZE; i++)
+		*dest[i] = *src[i];
+}
+
+/*True to*/
+bool PREFIX_equal(PREFIX_INT *left, PREFIX_INT *right)
+{
+	uint8_t i;
+
+	for (i = 0; i < PREFIX_INTSIZE; i++)
+		if (*left[i] != *right[i])
+			return false;
+
+	return true;
+}
+
+/*greater than*/
+bool PREFIX_greater(PREFIX_INT *left, PREFIX_INT *right)
+{
+	uint8_t i;
+	bool left_neg, right_neg;
+
+	left_neg  = PREFIX_isneg(left);
+	right_neg = PREFIX_isneg(right);
+
+	if (left_neg || right_neg) {
+		if (left_neg  && !right_neg)
+			return false;
+		else if (!left_neg && right_neg)
+			return true;
+	}
+
+	for (i = 0; i < PREFIX_INTSIZE; i++) {
+		if (*left[i] > *right[i])
+			return true;
+		else if (*left[i] < *right[i])
+			return false;
+	}
+
+	return false;
+}
+
+/*less than*/
+bool PREFIX_less(PREFIX_INT *left, PREFIX_INT *right)
+{
+	return !PREFIX_greater(left, right);
+}
+
+/*greater than or equal to*/
+bool PREFIX_greater_or_equal(PREFIX_INT *left, PREFIX_INT *right)
+{
+	return PREFIX_greater(left, right) || PREFIX_equal(left, right);
+}
+
+/*less than or equal to*/
+bool PREFIX_less_or_equal(PREFIX_INT *left, PREFIX_INT *right)
+{
+	return PREFIX_less(left, right) || PREFIX_equal(left, right);
+}
+
+/*Negatives not currently supported*/
+void PREFIX_add(PREFIX_INT *dest, PREFIX_INT *src)
+{
+	/*operator*/
+	uint16_t op;
+	uint8_t i;
+	bool dest_neg, src_neg;
+
+	src_neg  = PREFIX_isneg(src);
+	dest_neg = PREFIX_isneg(dest);
+
+	if (src_neg || dest_neg) {
+		PREFIX_math_overflow = true;
+		return;
+	}
+
+	for (i = 0; i < PREFIX_INTSIZE; i++) {
+		op        = *src[i];
+		op       += *dest[i];
+		*dest[i]  = op & 0xFF;
+
+		op >>= PREFIX_BITS_PER_BYTE;
+	}
+
+	if (i == PREFIX_INTSIZE && op != 0)
+		PREFIX_math_overflow = true;
+
+	if (!(src_neg || dest_neg) && PREFIX_isneg(dest))
+		PREFIX_math_overflow = true;
+}
+
+/*Negatives not currently supported*/
+void PREFIX_sub(PREFIX_INT *dest, PREFIX_INT *src)
+{
+	uint16_t op;
+	uint8_t i, j;
+	bool dest_neg, src_neg;
+			uint16_t tmp_op = 0;
+			bool got_borrow = false;
+	PREFIX_INT tmp_dest, tmp_src;
+
+	src_neg  = PREFIX_isneg(src);
+	dest_neg = PREFIX_isneg(dest);
+
+	if (src_neg || dest_neg)
+		PREFIX_math_overflow = true;
+
+	PREFIX_buf_to_buf(&tmp_src, src);
+	PREFIX_buf_to_buf(&tmp_dest, dest);
+	for (i = 0; i < PREFIX_INTSIZE; i++) {
+		op = tmp_dest[i];
+
+		if (tmp_src[i] > tmp_dest[i]) {
+			if (i == (PREFIX_INTSIZE-1))
+				PREFIX_math_overflow = true;
+
+			for (j = (i+1); j < PREFIX_INTSIZE; j++ )
+				if (tmp_dest[j]) {
+					tmp_dest[j] -= 1;
+					tmp_op = 0xFF;
+					got_borrow = true;
+					break;
+				}
+
+			if (!got_borrow)
+				PREFIX_math_overflow = true;
+
+			for (j--; j > i; j--)
+				tmp_src[j] = 0xFF;
+
+			op += tmp_op;
+		}
+
+		op       -= tmp_src[i];
+		*dest[i]  = op & 0xFF;
+	}
+}