static inline void swapEndiannessFor8ByteWord(char* c)
{
XOR_SWAP(c[0], c[7]);
XOR_SWAP(c[1], c[6]);
XOR_SWAP(c[2], c[5]);
XOR_SWAP(c[3], c[4]);
}
// reverse the given null-terminated string in place
void inplace_reverse(char * str)
{
if ( str)
{
char * end = str + strlen( str) - 1;
// swap the values in the two given variables
// XXX: fails when a and b refer to same memory location
# define XOR_SWAP(a,b) do\
{\
a ^= b;\
b ^= a;\
a ^= b;\
} while (0)
// walk inwards from both ends of the string,
// swapping until we get to the middle
while (str < end)
{
XOR_SWAP(*str, *end);
str++;
end--;
}
# undef XOR_SWAP
}
}
void reverse(char * str){
if (str){
char * end = str + strlen(str) - 1;
# define XOR_SWAP(a,b) do{\
a ^= b;\
b ^= a;\
a ^= b;\
} while (0)
while (str < end){
XOR_SWAP(*str, *end);
str++;
end--;
}
# undef XOR_SWAP
}
}
void rev(char* wurd)
{
if ( wurd ) {
char* end = wurd + strlen(wurd) - 1;
#define XOR_SWAP(a, b) do\
{\
a ^= b;\
b ^= a;\
a ^= b;\
} while (0)
while ( wurd < end ) {
XOR_SWAP(*wurd, *end);
wurd++;
end--;
}
#undef XOR_SWAP
}
}
VALUE method_my_reverse_xor(VALUE self)
{
VALUE dup = rb_str_dup(self);
char* start = RSTRING_PTR(dup);
char* end = start + RSTRING_LEN(dup) - 1;
#define XOR_SWAP(a,b) do\
{\
a ^= b;\
b ^= a;\
a ^= b;\
} while (0)
while(start < end)
{
XOR_SWAP(*start,*end);
start++;
end--;
}
#undef XOR_SWAP
return dup;
}
static inline void swapEndiannessFor4ByteWord(char* c)
{
XOR_SWAP(c[0], c[3]);
XOR_SWAP(c[1], c[2]);
}
