summaryrefslogtreecommitdiff
path: root/lib/string/stpcpy.c
diff options
context:
space:
mode:
authorRichard Qin <richard.qin.x@gmail.com>2026-07-10 11:31:46 +0800
committerRichard Qin <richard.qin.x@gmail.com>2026-07-10 11:31:46 +0800
commite90b72ec3082588b296956730bd2930cf8d5d671 (patch)
tree36ff6916af9b4176ea5a9662219d11e721f0b691 /lib/string/stpcpy.c
parent1767d390fbf3d0c65389de46caf0b6d43ef3b6ad (diff)
downloadlume-e90b72ec3082588b296956730bd2930cf8d5d671.tar.gz
lume-e90b72ec3082588b296956730bd2930cf8d5d671.tar.xz
refactor: promote new architecture to repository root
Archive the deprecated implementation under lume-legacy, make the new kernel the default root-level build, and update repository entry points without changing kernel behavior.
Diffstat (limited to 'lib/string/stpcpy.c')
-rw-r--r--lib/string/stpcpy.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/lib/string/stpcpy.c b/lib/string/stpcpy.c
new file mode 100644
index 0000000..0c1f1b4
--- /dev/null
+++ b/lib/string/stpcpy.c
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: MIT */
+/* Derived from musl libc (Copyright © 2005-2020 Rich Felker, et al.) */
+
+#include <string.h>
+#include <stdint.h>
+#include <limits.h>
+
+#define ALIGN (sizeof(size_t))
+#define ONES ((size_t)-1/UCHAR_MAX)
+#define HIGHS (ONES * (UCHAR_MAX/2+1))
+#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
+
+char *__stpcpy(char *restrict d, const char *restrict s)
+{
+#ifdef __GNUC__
+ typedef size_t __attribute__((__may_alias__)) word;
+ word *wd;
+ const word *ws;
+ if ((uintptr_t)s % ALIGN == (uintptr_t)d % ALIGN) {
+ for (; (uintptr_t)s % ALIGN; s++, d++)
+ if (!(*d=*s)) return d;
+ wd=(void *)d; ws=(const void *)s;
+ for (; !HASZERO(*ws); *wd++ = *ws++);
+ d=(void *)wd; s=(const void *)ws;
+ }
+#endif
+ for (; (*d=*s); s++, d++);
+
+ return d;
+}
+
+weak_alias(__stpcpy, stpcpy);