LibCore: Add syscall wrapper for open()

Userland/Libraries/LibCore/System.cpp

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/String.h>
 #include <LibCore/System.h>
 #include <LibSystem/syscall.h>
 #include <fcntl.h>
@@ -92,4 +93,26 @@ ErrorOr<void> munmap(void* address, size_t size)
  return {};
 }
 
+ErrorOr<int> open(StringView path, int options, ...)
+{
+ if (!path.characters_without_null_termination())
+ return Error::from_syscall("open"sv, -EFAULT);
+ va_list ap;
+ va_start(ap, options);
+ auto mode = (mode_t)va_arg(ap, unsigned);
+ va_end(ap);
+#ifdef __serenity__
+ Syscall::SC_open_params params { AT_FDCWD, { path.characters_without_null_termination(), path.length() }, options, mode };
+ int rc = syscall(SC_open, &params);
+ HANDLE_SYSCALL_RETURN_VALUE("open"sv, rc, rc);
+#else
+ // NOTE: We have to ensure that the path is null-terminated.
+ String path_string;
+ int rc = ::open(path_string.characters(), options, mode);
+ if (rc < 0)
+ return Error::from_syscall("open"sv, -errno);
+ return rc;
+#endif
+}
+
 }

Userland/Libraries/LibCore/System.h

@@ -22,5 +22,6 @@ ErrorOr<struct stat> fstat(int fd);
 ErrorOr<int> fcntl(int fd, int command, ...);
 ErrorOr<void*> mmap(void* address, size_t, int protection, int flags, int fd, off_t, size_t alignment = 0, StringView name = {});
 ErrorOr<void> munmap(void* address, size_t);
+ErrorOr<int> open(StringView path, int options, ...);
 
 }