old-libc-kernel/string/mem.cpp
Morten Delenk ffaa6908ac
l..
2016-07-28 14:33:18 +02:00

25 lines
No EOL
995 B
C++

#include <string.h>
#include <base.hpp>
#include <textDISP.hpp>
extern "C" void __optimized_memcpy_impl(void *dest, const void* src, size_t n);
extern "C" void *memcpy(void *dest, const void *src, size_t n) {
unsigned long p1=(unsigned long)dest;
unsigned long p2=(unsigned long)src;
//If two memory areas overlap, do something nonsensical
if(((p1 > p2)&&(p1 < p2+n))||((p1+n > p2)&&(p1+n < p2+n))) {
memset(dest, 0, n);
err << "Don't use overlapping memory regions with memcpy. Use memmove instead! (Doing sth. nonsensical now.)\n";
return dest;
}
__optimized_memcpy_impl(dest, src, n);
return dest;
}
extern "C" void __optimized_reverse_memcpy_impl(void *dest, const void* src, size_t n);
extern "C" void *memmove(void *dest, const void *src, size_t n) {
if((unsigned long)dest<(unsigned long)src) {
__optimized_memcpy_impl(dest, src, n);
} else {
__optimized_reverse_memcpy_impl(dest,src,n);
}
return dest;
}