[PATCH 07/15] tools/nolibc: add support for access() and faccessat()

[Thomas Weißschuh]

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

Signed-off-by: Thomas Weißschuh <thomas.weisssc...@linutronix.de>
---
 tools/include/nolibc/unistd.h                | 28 ++++++++++++++++++++++++++++
 tools/testing/selftests/nolibc/nolibc-test.c |  2 ++
 2 files changed, 30 insertions(+)

diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
index 
ac7d53d986cd11ac84dd0a17e5a7055c779b2b10..a18e318399880dec12284ea86cb91cf46cfc4aaa
 100644
--- a/tools/include/nolibc/unistd.h
+++ b/tools/include/nolibc/unistd.h
@@ -17,6 +17,34 @@
 #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 
b6724c314766b0cf34d7cae5cac28a9102ebe66e..7090e6b7c37e49afe751835bbff6a7af4f4fcf2a
 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1109,6 +1109,8 @@ 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;

-- 
2.49.0