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

/*  ntapi: Native API core library                      */

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

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

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

#include <psxtypes/psxtypes.h>

#include <pemagine/pemagine.h>

#include <ntapi/nt_sysinfo.h>

#include <ntapi/nt_memory.h>

#include <ntapi/ntapi.h>

#include "ntapi_impl.h"

int32_t __stdcall __ntapi_tt_get_system_info_snapshot(

	__in_out nt_system_information_snapshot * sys_info_snapshot)

{

	int32_t		status;

	/* pre-allocated buffer? */

	if (sys_info_snapshot->buffer)

		status = __ntapi->zw_query_system_information(

			sys_info_snapshot->sys_info_class,

			sys_info_snapshot->buffer,

			sys_info_snapshot->max_len,

			&sys_info_snapshot->info_len);

	else {

		/* set initial buffer size */

		sys_info_snapshot->max_len = NT_ALLOCATION_GRANULARITY;

		/* allocate initial buffer */

		status = __ntapi->zw_allocate_virtual_memory(

			NT_CURRENT_PROCESS_HANDLE,

			&sys_info_snapshot->buffer,

			0,

			&sys_info_snapshot->max_len,

			NT_MEM_COMMIT,

			NT_PAGE_READWRITE);

		/* verification */

		if (status != NT_STATUS_SUCCESS)

			return status;

		/* loop until buffer is large enough to satisfy the system */

		while ((status = __ntapi->zw_query_system_information(

					sys_info_snapshot->sys_info_class,

					sys_info_snapshot->buffer,

					sys_info_snapshot->max_len,

					&sys_info_snapshot->info_len))

				== NT_STATUS_INFO_LENGTH_MISMATCH) {

			/* free previously allocated memory */

			status = __ntapi->zw_free_virtual_memory(

					NT_CURRENT_PROCESS_HANDLE,

					&sys_info_snapshot->buffer,

					&sys_info_snapshot->max_len,

					NT_MEM_RELEASE);

			/* verification */

			if (status != NT_STATUS_SUCCESS)

				return status;

			/* reset buffer and increase buffer size */

			sys_info_snapshot->buffer   = 0;

			sys_info_snapshot->max_len += NT_ALLOCATION_GRANULARITY;

			/* reallocate buffer memory */

			status = __ntapi->zw_allocate_virtual_memory(

					NT_CURRENT_PROCESS_HANDLE,

					&sys_info_snapshot->buffer,

					0,

					&sys_info_snapshot->max_len,

					NT_MEM_COMMIT,

					NT_PAGE_READWRITE);

			/* verification */

			if (status != NT_STATUS_SUCCESS)

				return status;

		}

	}

	/* verification */

	if (status == NT_STATUS_SUCCESS) {

		sys_info_snapshot->pcurrent = sys_info_snapshot->buffer;

		return NT_STATUS_SUCCESS;

	} else {

		sys_info_snapshot->pcurrent = (void *)0;

		return status;

	}

}