From 0b44a0315b47dd8eced9f3b7f31580cf14bbfc01 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 12 Feb 2011 00:22:29 -0500 Subject: initial check-in, version 0.5.0 --- src/string/stpcpy.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 src/string/stpcpy.c (limited to 'src/string/stpcpy.c') diff --git a/src/string/stpcpy.c b/src/string/stpcpy.c new file mode 100644 index 00000000..10ca4933 --- /dev/null +++ b/src/string/stpcpy.c @@ -0,0 +1,29 @@ +#include +#include +#include +#include +#include "libc.h" + +#define ALIGN (sizeof(size_t)-1) +#define ONES ((size_t)-1/UCHAR_MAX) +#define HIGHS (ONES * (UCHAR_MAX/2+1)) +#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS) + +char *__stpcpy(char *d, const char *s) +{ + size_t *wd; + const size_t *ws; + + if (((uintptr_t)s & ALIGN) == ((uintptr_t)d & ALIGN)) { + for (; (*d=*s) && ((uintptr_t)s & ALIGN); s++, d++); + if (!*s) return d; + wd=(void *)d; ws=(const void *)s; + for (; !HASZERO(*ws); *wd++ = *ws++); + d=(void *)wd; s=(const void *)ws; + } + for (; (*d=*s); s++, d++); + + return d; +} + +weak_alias(__stpcpy, stpcpy); -- cgit v1.2.1