From: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Date: Mon, 28 Apr 2025 12:40:08 +0000 (+0200)
Subject: tools/nolibc: add support for access() and faccessat()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1e10b8534f5af42b7da528c254595f2a0cf4997d;p=users%2Fdwmw2%2Flinux.git

tools/nolibc: add support for access() and faccessat()

This is used in various selftests and will be handy when integrating
those with nolibc.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250428-nolibc-misc-v2-7-3c043eeab06c@linutronix.de
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---

diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
index ed253305fdbaf..25bfc7732ec7e 100644
--- a/tools/include/nolibc/unistd.h
+++ b/tools/include/nolibc/unistd.h
@@ -20,6 +20,34 @@
 #define STDOUT_FILENO 1
 #define STDERR_FILENO 2
 
+#define F_OK 0
+#define X_OK 1
+#define W_OK 2
+#define R_OK 4
+
+/*
+ * int access(const char *path, int amode);
+ * int faccessat(int fd, const char *path, int amode, int flag);
+ */
+
+static __attribute__((unused))
+int sys_faccessat(int fd, const char *path, int amode, int flag)
+{
+       return my_syscall4(__NR_faccessat, fd, path, amode, flag);
+}
+
+static __attribute__((unused))
+int faccessat(int fd, const char *path, int amode, int flag)
+{
+	return __sysret(sys_faccessat(fd, path, amode, flag));
+}
+
+static __attribute__((unused))
+int access(const char *path, int amode)
+{
+	return faccessat(AT_FDCWD, path, amode, 0);
+}
+
 
 static __attribute__((unused))
 int msleep(unsigned int msecs)
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 14a27bc6c83e4..10db118b8b111 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1112,6 +1112,8 @@ int run_syscall(int min, int max)
 		 * test numbers.
 		 */
 		switch (test + __LINE__ + 1) {
+		CASE_TEST(access);            EXPECT_SYSZR(proc, access("/proc/self", R_OK)); break;
+		CASE_TEST(access_bad);        EXPECT_SYSER(proc, access("/proc/self", W_OK), -1, EPERM); break;
 		CASE_TEST(getpid);            EXPECT_SYSNE(1, getpid(), -1); break;
 		CASE_TEST(getppid);           EXPECT_SYSNE(1, getppid(), -1); break;
 		CASE_TEST(gettid);            EXPECT_SYSNE(has_gettid, gettid(), -1); break;