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

/*  ntapi: Native API core library                      */

/*  Copyright (C) 2013--2021  SysDeer Technologies, LLC */

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

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

#include <ntapi/ntapi.h>

#include <ntapi/nt_file.h>

#include <ntapi/nt_fsctl.h>

#include <ntapi/nt_mount.h>

#include <ntapi/nt_istat.h>

#include "ntapi_impl.h"

int32_t __stdcall __ntapi_tt_istat(

	__in	void *			hfile,

	__out	nt_istat *		istat,

	__in	uint32_t		infolen,

	__out	uintptr_t *		buffer,

	__in	uint32_t		buffer_size,

	__in	uint32_t		flags)

{

	int32_t			status;

	nt_iosb			iosb;

	nt_unicode_string *	sdev;

	wchar16_t *		wch;

	wchar16_t *		wch_mark;

	wchar16_t *		wch_cap;

	uint32_t		hash;

	uint32_t		written;

	/* validaton */

	if (infolen < sizeof(*istat))

		return NT_STATUS_INFO_LENGTH_MISMATCH;

	/* init */

	__ntapi->tt_aligned_block_memset(

		istat,0,sizeof(*istat));

	istat->hfile           = hfile;

	istat->dev_name_maxlen = (uint16_t)infolen - sizeof(*istat);

	/* sigh */

	if (buffer_size >= 65536)

		buffer_size = 65535;

	/* file index number */

	if (!(flags & NT_ISTAT_DEV_NAME_ONLY))

		if ((status = __ntapi->zw_query_information_file(

				hfile,

				&iosb,

				&istat->fii,

				sizeof(istat->fii),

				NT_FILE_INTERNAL_INFORMATION)))

			return status;

	/* attributes & reparse tag information */

	if (!(flags & NT_ISTAT_DEV_NAME_ONLY))

		if ((status = __ntapi->zw_query_information_file(

				hfile,

				&iosb,

				&istat->ftagi,

				sizeof(istat->ftagi),

				NT_FILE_ATTRIBUTE_TAG_INFORMATION)))

			return status;

	/* system-unique device name */

	if ((status = __ntapi->zw_query_object(

			hfile,

			NT_OBJECT_NAME_INFORMATION,

			buffer,

			buffer_size,

			&written)))

		return status;

	sdev = (nt_unicode_string *)buffer;

	wch  = sdev->buffer;

	if (sdev->strlen < __DEVICE_PATH_PREFIX_LEN)

		return NT_STATUS_NOT_SUPPORTED;

	if ((wch[0] != '\\')

			|| (wch[1] != 'D')

			|| (wch[2] != 'e')

			|| (wch[3] != 'v')

			|| (wch[4] != 'i')

			|| (wch[5] != 'c')

			|| (wch[6] != 'e')

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

		return NT_STATUS_NOT_SUPPORTED;

	if ((sdev->strlen >= __DEVICE_MUP_PREFIX_LEN)

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

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

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

			&& (wch[11]=='\\')) {

		hash = __DEVICE_MUP_PREFIX_HASH;

		istat->flags |= NT_STATFS_MUP_DEVICE;

		wch_mark = &wch[12];

		wch      = wch_mark;

		for (; *wch!='\\'; )

			wch++;

		wch++;

	} else {

		wch_mark = &wch[8];

		wch      = wch_mark;

		hash     = __DEVICE_PATH_PREFIX_HASH;

	}

	wch_cap = sdev->buffer + (sdev->strlen / sizeof(wchar16_t));

	for (; wch

		wch++;

	istat->obj_name_strlen = sdev->strlen;

	istat->obj_name_maxlen = istat->dev_name_maxlen;

	istat->dev_name_strlen = sizeof(uint16_t) * (uint16_t)(wch - sdev->buffer);

	istat->dev_name_hash   = __ntapi->tt_buffer_crc32(

					hash,wch_mark,

					sizeof(wchar16_t) * (wch - wch_mark));

	if (!(flags & NT_ISTAT_DEV_NAME_COPY))

		return NT_STATUS_SUCCESS;

	else if (istat->dev_name_maxlen < istat->dev_name_strlen)

		return NT_STATUS_BUFFER_TOO_SMALL;

	__ntapi->tt_memcpy_utf16(

		istat->dev_name,

		sdev->buffer,

		istat->dev_name_strlen);

	return status;

}