--- a/common.h Mon Jul 30 11:34:57 2012 +0300
+++ b/common.h Sat Aug 11 19:35:47 2012 +0300
@@ -118,6 +118,7 @@
// Byte datatype
typedef unsigned long int word;
+typedef unsigned char byte;
// Keywords
#define NUM_KEYWORDS 20
@@ -126,7 +127,7 @@
#endif
bool IsKeyword (str s);
-// Script mark -- also serves as reference type
+// Script mark and reference
struct ScriptMark {
int type;
str name;
@@ -139,21 +140,23 @@
};
// ====================================================================
+// Generic union
+template <class T> union union_t {
+ T val;
+ byte b[sizeof (T)];
+ char c[sizeof (T)];
+ double d;
+ float f;
+ int i;
+ word w;
+};
+
+// ====================================================================
// Finds a byte in the given value.
-template <class T> unsigned char GetByteIndex (T a, unsigned int b) {
- if (b >= sizeof (T))
- error ("CharByte: tried to get byte %u out of a %u-byte %s\n",
- b, sizeof (T), typeid (T).name());
-
- unsigned long p1 = pow<unsigned long> (256, b);
- unsigned long p2 = pow<unsigned long> (256, b+1);
- unsigned long r = (a % p2) / p1;
-
- if (r > 256)
- error ("DataBuffer::CharByte: result %lu too big!", r);
-
- unsigned char ur = static_cast<unsigned char> (r);
- return ur;
+template <class T> inline unsigned char GetByteIndex (T a, unsigned int b) {
+ union_t<T> uni;
+ uni.val = a;
+ return uni.b[b];
}
#endif // __COMMON_H__
\ No newline at end of file