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

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

/*  Copyright (C) 2013--2020  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"

pe_api int32_t pe_open_image_from_addr(

	__out	void **			himage,

	__in	void *			addr,

	__out	uintptr_t *		buffer,

	__in	size_t			bufsize,

	__in	uint32_t		oattr,

	__in	uint32_t		desired_access,

	__in	uint32_t		share_access,

	__in	uint32_t		open_options)

{

	struct os_oa			oa;

	struct os_iosb			iosb;

	void *				hntdll;

	os_zw_open_file *		zw_open_file;

	struct pe_unicode_str		path;

	struct pe_ldr_tbl_entry *	lentry;

	wchar16_t *			name;

	wchar16_t *			cap;

	wchar16_t *			src;

	wchar16_t *			dst;

	wchar16_t *			mark;

	/* init */

	if (!(hntdll = pe_get_ntdll_module_handle()))

		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 image containing addr */

	if (!(lentry = pe_get_ldr_entry_from_addr(addr)))

		return OS_STATUS_INTERNAL_ERROR;

	if (bufsize - 4*sizeof(wchar16_t) < lentry->full_dll_name.strlen)

		return OS_STATUS_BUFFER_TOO_SMALL;

	name = lentry->full_dll_name.buffer;

	mark = (wchar16_t *)buffer;

	dst  = mark;

	if (name[1] == ':') {

		*dst++ = '\\';

		*dst++ = '?';

		*dst++ = '?';

		*dst++ = '\\';

	}

	src = name;

	cap  = &dst[lentry->full_dll_name.strlen / sizeof(wchar16_t)];

	for (; dst

		*dst++ = *src++;

	*dst = 0;

	path.strlen = sizeof(wchar16_t) * (cap - mark);

	path.maxlen = 0;

	path.buffer = mark;

	/* oa */

	oa.len      = sizeof(struct os_oa);

	oa.root_dir = 0;

	oa.obj_name = &pat;;

	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 image */

	return zw_open_file(

		himage,

		desired_access,

		&oa,&iosb,

		share_access,

		open_options | OS_FILE_NON_DIRECTORY_FILE);

}