/*****************************************************************************/

/*  pemagination: a (virtual) tour into portable bits and executable bytes   */

/*  Copyright (C) 2013--2017  Z. Gilboa                                      */

/*  Released under GPLv2 and GPLv3; see COPYING.PEMAGINE.                    */

/*****************************************************************************/

#include <psxtypes/psxtypes.h>

#include <pemagine/pemagine.h>

#include <pemagine/pe_structs.h>

#include "pe_os.h"

int32_t pe_open_physical_parent_directory(

	__out	void **		hparent,

	__in	void *		href,

	__out	uintptr_t *	buffer,

	__in	uint32_t	bufsize,

	__in	uint32_t	oattr,

	__in	uint32_t	desired_access,

	__in	uint32_t	share_access,

	__in	uint32_t	open_options)

{

	int32_t			status;

	struct os_oa		oa;

	struct os_iosb		iosb;

	wchar16_t *		wch;

	wchar16_t *		root;

	struct pe_unicode_str *	path;

	uint32_t		len;

	int			mup;

	void *			hntdll;

	os_zw_query_object *	zw_query_object;

	os_zw_open_file *	zw_open_file;

	/* init */

	path = (struct pe_unicode_str *)buffer;

	if (!(hntdll = pe_get_ntdll_module_handle()))

		return OS_STATUS_INTERNAL_ERROR;

	if (!(zw_query_object = (os_zw_query_object *)pe_get_procedure_address(

			hntdll,"ZwQueryObject")))

		return OS_STATUS_INTERNAL_ERROR;

	if (!(zw_open_file = (os_zw_open_file *)pe_get_procedure_address(

			hntdll,"ZwOpenFile")))

		return OS_STATUS_INTERNAL_ERROR;

	/* native path of base directory */

	if ((status = zw_query_object(

			href,

			OS_OBJECT_NAME_INFORMATION,

			path,

			bufsize,

			&len)))

		return status;

	/* integrity */

	if (len == sizeof(struct pe_unicode_str))

		return OS_STATUS_BAD_FILE_TYPE;

	/* device root directory */

	root = path->buffer;

	wch  = path->buffer + (path->strlen / sizeof(uint16_t));

	if ((wch < &root[8])

			|| (root[0] != '\\')

			|| (root[1] != 'D') || (root[2] != 'e')

			|| (root[3] != 'v') || (root[4] != 'i')

			|| (root[5] != 'c') || (root[6] != 'e')

			|| (root[7] != '\\'))

		return OS_STATUS_INTERNAL_ERROR;

	mup = (wch > &root[11])

		&& (root[8]=='M')

		&& (root[9]=='u')

		&& (root[10]=='p')

		&& (root[11]=='\\');

	root = mup ? &root[12] : &root[8];

	for (; (root

		root++;

	if (root == wch)

		return OS_STATUS_INTERNAL_ERROR;

	if (mup)

		for (root++; (root

			root++;

	if (root == wch)

		return OS_STATUS_INTERNAL_ERROR;

	if (&root[1] == wch)

		return OS_STATUS_MORE_PROCESSING_REQUIRED;

	if (wch[-1] == '\\')

		wch--;

	/* physical parent directory path */

	for (root++; (wch>=root) && (wch[-1]!='\\'); )

		wch--;

	path->strlen = (uint16_t)(wch - path->buffer) * sizeof(uint16_t);

	path->maxlen = 0;

	/* oa */

	oa.len      = sizeof(struct os_oa);

	oa.root_dir = 0;

	oa.obj_name = path;

	oa.obj_attr = oattr;

	oa.sec_desc = 0;

	oa.sec_qos  = 0;

	/* default access */

	desired_access = desired_access

		? desired_access

		: OS_SEC_SYNCHRONIZE | OS_FILE_READ_ATTRIBUTES | OS_FILE_READ_ACCESS;

	/* open parent directory */

	return zw_open_file(

		hparent,

		desired_access,

		&oa,&iosb,

		share_access,

		open_options | OS_FILE_DIRECTORY_FILE);

}