Kernel: Implement SYS_FSTAT

libc/sys/stat.cpp

@@ -1,14 +1,46 @@
+#include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/syscall.h>
 #include <unistd.h>
 
+int fstat(int fildes, struct stat* buf)
+{
+	return syscall(SYS_FSTAT, fildes, buf);
+}
+
+int fstatat(int fd, const char* __restrict path, struct stat* __restrict buf, int flag)
+{
+	if (flag & ~AT_SYMLINK_NOFOLLOW)
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	int target = openat(fd, path, (flag & AT_SYMLINK_NOFOLLOW) ? O_NOFOLLOW : 0);
+	if (target == -1)
+		return -1;
+	int ret = fstat(target, buf);
+	close(target);
+	return ret;
+}
+
 int lstat(const char* __restrict path, struct stat* __restrict buf)
 {
-    return syscall(SYS_STAT, path, buf, O_RDONLY | O_NOFOLLOW);
+	int fd = open(path, O_SEARCH | O_NOFOLLOW);
+	if (fd == -1)
+		return -1;
+	int ret = fstat(fd, buf);
+	close(fd);
+	return ret;
 }
 
 int stat(const char* __restrict path, struct stat* __restrict buf)
 {
-    return syscall(SYS_STAT, path, buf, O_RDONLY);
+	int fd = open(path, O_SEARCH);
+	if (fd == -1)
+		return -1;
+	int ret = fstat(fd, buf);
+	close(fd);
+	return ret;
 }