nativelibc/symlink.c

/*	A part of the Native C Library for Windows NT
	Copyright 2007-2015 PC GO Ld.

	This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
*/

#include <windows.h>
#include <nt.h>
#include <errno.h>
#include <pathname.h>

#include <stdio.h>

int symlink(const char *oldpath, const char *newpath) {
	if(!oldpath || !newpath) {
		errno = EFAULT;
		return -1;
	}

	void *handle;
	UNICODE_STRING old_path;
	UNICODE_STRING new_path;
	RtlCreateUnicodeStringFromAsciiz(&old_path, oldpath);
	RtlCreateUnicodeStringFromAsciiz(&new_path, newpath);
	if(old_path.Length > sizeof(wchar_t) && old_path.Buffer[old_path.Length / sizeof(wchar_t) - 1] == L'/') {
		old_path.Buffer[old_path.Length / sizeof(wchar_t) - 1] = 0;
		old_path.Length -= sizeof(wchar_t);
		old_path.MaximumLength -= sizeof(wchar_t);
	}
	PATHNAME_UNIX2NT_UTF16_STRUCT(old_path);
	PATHNAME_UNIX2NT_UTF16_STRUCT(new_path);
	OBJECT_ATTRIBUTES new_object = { sizeof(OBJECT_ATTRIBUTES), NULL, &new_path, OBJ_PERMANENT, NULL, NULL };
	long int status = NtCreateSymbolicLinkObject(&handle, SYMBOLIC_LINK_ALL_ACCESS, &new_object, &old_path);
	RtlFreeUnicodeString(&old_path);
	RtlFreeUnicodeString(&new_path);
	if(__set_errno_from_ntstatus(status)) return -1;
	if(__set_errno_from_ntstatus(NtClose(handle))) return -1;
	return 0;
}