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-rw-r--r--libc-top-half/musl/src/string/strchrnul.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/string/strchrnul.c b/libc-top-half/musl/src/string/strchrnul.c
new file mode 100644
index 0000000..39e2635
--- /dev/null
+++ b/libc-top-half/musl/src/string/strchrnul.c
@@ -0,0 +1,28 @@
+#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 *__strchrnul(const char *s, int c)
+{
+ c = (unsigned char)c;
+ if (!c) return (char *)s + strlen(s);
+
+#ifdef __GNUC__
+ typedef size_t __attribute__((__may_alias__)) word;
+ const word *w;
+ for (; (uintptr_t)s % ALIGN; s++)
+ if (!*s || *(unsigned char *)s == c) return (char *)s;
+ size_t k = ONES * c;
+ for (w = (void *)s; !HASZERO(*w) && !HASZERO(*w^k); w++);
+ s = (void *)w;
+#endif
+ for (; *s && *(unsigned char *)s != c; s++);
+ return (char *)s;
+}
+
+weak_alias(__strchrnul, strchrnul);