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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/strcspn.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/strcspn.c')
-rw-r--r--lib/string/strcspn.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/lib/string/strcspn.c b/lib/string/strcspn.c
new file mode 100644
index 0000000..ba55fe6
--- /dev/null
+++ b/lib/string/strcspn.c
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: MIT */
+/* Derived from musl libc (Copyright © 2005-2020 Rich Felker, et al.) */
+
+#include <string.h>
+
+#define BITOP(a,b,op) \
+ ((a)[(size_t)(b)/(8*sizeof *(a))] op (size_t)1<<((size_t)(b)%(8*sizeof *(a))))
+
+size_t strcspn(const char *s, const char *c)
+{
+ const char *a = s;
+ size_t byteset[32/sizeof(size_t)];
+
+ if (!c[0] || !c[1]) return __strchrnul(s, *c)-a;
+
+ memset(byteset, 0, sizeof byteset);
+ for (; *c && BITOP(byteset, *(unsigned char *)c, |=); c++);
+ for (; *s && !BITOP(byteset, *(unsigned char *)s, &); s++);
+ return s-a;
+}