aboutsummaryrefslogtreecommitdiff
path: root/primedev/mods/autodownload/moddownloader.cpp
blob: 1e3c6af68fd1f1da41fec7ee5f240e0c68e855a0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
#include "moddownloader.h"
#include "util/utils.h"
#include <rapidjson/fwd.h>
#include <mz_strm_mem.h>
#include <mz.h>
#include <mz_strm.h>
#include <mz_zip.h>
#include <mz_compat.h>
#include <thread>
#include <future>
#include <bcrypt.h>
#include <winternl.h>
#include <fstream>

ModDownloader* g_pModDownloader;

ModDownloader::ModDownloader()
{
	spdlog::info("Mod downloader initialized");

	// Initialise mods list URI
	char* clachar = strstr(GetCommandLineA(), CUSTOM_MODS_URL_FLAG);
	if (clachar)
	{
		std::string url;
		int iFlagStringLength = strlen(CUSTOM_MODS_URL_FLAG);
		std::string cla = std::string(clachar);
		if (strncmp(cla.substr(iFlagStringLength, 1).c_str(), "\"", 1))
		{
			int space = cla.find(" ");
			url = cla.substr(iFlagStringLength, space - iFlagStringLength);
		}
		else
		{
			std::string quote = "\"";
			int quote1 = cla.find(quote);
			int quote2 = (cla.substr(quote1 + 1)).find(quote);
			url = cla.substr(quote1 + 1, quote2);
		}
		spdlog::info("Found custom verified mods URL in command line argument: {}", url);
		modsListUrl = strdup(url.c_str());
	}
	else
	{
		spdlog::info("Custom verified mods URL not found in command line arguments, using default URL.");
		modsListUrl = strdup(DEFAULT_MODS_LIST_URL);
	}
}

size_t WriteToString(void* ptr, size_t size, size_t count, void* stream)
{
	((std::string*)stream)->append((char*)ptr, 0, size * count);
	return size * count;
}

void ModDownloader::FetchModsListFromAPI()
{
	std::thread requestThread(
		[this]()
		{
			CURLcode result;
			CURL* easyhandle;
			rapidjson::Document verifiedModsJson;
			std::string url = modsListUrl;

			curl_global_init(CURL_GLOBAL_ALL);
			easyhandle = curl_easy_init();
			std::string readBuffer;

			// Fetching mods list from GitHub repository
			curl_easy_setopt(easyhandle, CURLOPT_CUSTOMREQUEST, "GET");
			curl_easy_setopt(easyhandle, CURLOPT_TIMEOUT, 30L);
			curl_easy_setopt(easyhandle, CURLOPT_URL, url.c_str());
			curl_easy_setopt(easyhandle, CURLOPT_FAILONERROR, 1L);
			curl_easy_setopt(easyhandle, CURLOPT_WRITEDATA, &readBuffer);
			curl_easy_setopt(easyhandle, CURLOPT_WRITEFUNCTION, WriteToString);
			result = curl_easy_perform(easyhandle);
			ScopeGuard cleanup([&] { curl_easy_cleanup(easyhandle); });

			if (result == CURLcode::CURLE_OK)
			{
				spdlog::info("Mods list successfully fetched.");
			}
			else
			{
				spdlog::error("Fetching mods list failed: {}", curl_easy_strerror(result));
				return;
			}

			// Load mods list into local state
			spdlog::info("Loading mods configuration...");
			verifiedModsJson.Parse(readBuffer);
			for (auto i = verifiedModsJson.MemberBegin(); i != verifiedModsJson.MemberEnd(); ++i)
			{
				std::string name = i->name.GetString();
				std::string dependency = i->value["DependencyPrefix"].GetString();

				std::unordered_map<std::string, VerifiedModVersion> modVersions;
				rapidjson::Value& versions = i->value["Versions"];
				assert(versions.IsArray());
				for (auto& attribute : versions.GetArray())
				{
					assert(attribute.IsObject());
					std::string version = attribute["Version"].GetString();
					std::string checksum = attribute["Checksum"].GetString();
					modVersions.insert({version, {.checksum = checksum}});
				}

				VerifiedModDetails modConfig = {.dependencyPrefix = dependency, .versions = modVersions};
				verifiedMods.insert({name, modConfig});
				spdlog::info("==> Loaded configuration for mod \"" + name + "\"");
			}

			spdlog::info("Done loading verified mods list.");
		});
	requestThread.detach();
}

size_t WriteData(void* ptr, size_t size, size_t nmemb, FILE* stream)
{
	size_t written;
	written = fwrite(ptr, size, nmemb, stream);
	return written;
}

int ModDownloader::ModFetchingProgressCallback(
	void* ptr, curl_off_t totalDownloadSize, curl_off_t finishedDownloadSize, curl_off_t totalToUpload, curl_off_t nowUploaded)
{
	if (totalDownloadSize != 0 && finishedDownloadSize != 0)
	{
		ModDownloader* instance = static_cast<ModDownloader*>(ptr);
		auto currentDownloadProgress = roundf(static_cast<float>(finishedDownloadSize) / totalDownloadSize * 100);
		instance->modState.progress = finishedDownloadSize;
		instance->modState.total = totalDownloadSize;
		instance->modState.ratio = currentDownloadProgress;
	}

	return 0;
}

std::optional<fs::path> ModDownloader::FetchModFromDistantStore(std::string_view modName, std::string_view modVersion)
{
	// Retrieve mod prefix from local mods list, or use mod name as mod prefix if bypass flag is set
	std::string modPrefix = strstr(GetCommandLineA(), VERIFICATION_FLAG) ? modName.data() : verifiedMods[modName.data()].dependencyPrefix;
	// Build archive distant URI
	std::string archiveName = std::format("{}-{}.zip", modPrefix, modVersion.data());
	std::string url = STORE_URL + archiveName;
	spdlog::info(std::format("Fetching mod archive from {}", url));

	// Download destination
	std::filesystem::path downloadPath = std::filesystem::temp_directory_path() / archiveName;
	spdlog::info(std::format("Downloading archive to {}", downloadPath.generic_string()));

	// Update state
	modState.state = DOWNLOADING;

	// Download the actual archive
	bool failed = false;
	FILE* fp = fopen(downloadPath.generic_string().c_str(), "wb");
	CURLcode result;
	CURL* easyhandle;
	easyhandle = curl_easy_init();

	curl_easy_setopt(easyhandle, CURLOPT_URL, url.data());
	curl_easy_setopt(easyhandle, CURLOPT_FAILONERROR, 1L);

	// abort if slower than 30 bytes/sec during 10 seconds
	curl_easy_setopt(easyhandle, CURLOPT_LOW_SPEED_TIME, 10L);
	curl_easy_setopt(easyhandle, CURLOPT_LOW_SPEED_LIMIT, 30L);

	curl_easy_setopt(easyhandle, CURLOPT_WRITEDATA, fp);
	curl_easy_setopt(easyhandle, CURLOPT_WRITEFUNCTION, WriteData);
	curl_easy_setopt(easyhandle, CURLOPT_NOPROGRESS, 0L);
	curl_easy_setopt(easyhandle, CURLOPT_XFERINFOFUNCTION, ModDownloader::ModFetchingProgressCallback);
	curl_easy_setopt(easyhandle, CURLOPT_XFERINFODATA, this);
	result = curl_easy_perform(easyhandle);
	ScopeGuard cleanup(
		[&]
		{
			curl_easy_cleanup(easyhandle);
			fclose(fp);
		});

	if (result == CURLcode::CURLE_OK)
	{
		spdlog::info("Mod archive successfully fetched.");
		return std::optional<fs::path>(downloadPath);
	}
	else
	{
		spdlog::error("Fetching mod archive failed: {}", curl_easy_strerror(result));
		return std::optional<fs::path>();
	}
}

bool ModDownloader::IsModLegit(fs::path modPath, std::string_view expectedChecksum)
{
	if (strstr(GetCommandLineA(), VERIFICATION_FLAG))
	{
		spdlog::info("Bypassing mod verification due to flag set up.");
		return true;
	}

	// Update state
	modState.state = CHECKSUMING;

	NTSTATUS status;
	BCRYPT_ALG_HANDLE algorithmHandle = NULL;
	BCRYPT_HASH_HANDLE hashHandle = NULL;
	std::vector<uint8_t> hash;
	DWORD hashLength = 0;
	DWORD resultLength = 0;
	std::stringstream ss;

	constexpr size_t bufferSize {1 << 12};
	std::vector<char> buffer(bufferSize, '\0');
	std::ifstream fp(modPath.generic_string(), std::ios::binary);

	ScopeGuard cleanup(
		[&]
		{
			if (NULL != hashHandle)
			{
				BCryptDestroyHash(hashHandle); // Handle to hash/MAC object which needs to be destroyed
			}

			if (NULL != algorithmHandle)
			{
				BCryptCloseAlgorithmProvider(
					algorithmHandle, // Handle to the algorithm provider which needs to be closed
					0); // Flags
			}
		});

	// Open an algorithm handle
	// This sample passes BCRYPT_HASH_REUSABLE_FLAG with BCryptAlgorithmProvider(...) to load a provider which supports reusable hash
	status = BCryptOpenAlgorithmProvider(
		&algorithmHandle, // Alg Handle pointer
		BCRYPT_SHA256_ALGORITHM, // Cryptographic Algorithm name (null terminated unicode string)
		NULL, // Provider name; if null, the default provider is loaded
		BCRYPT_HASH_REUSABLE_FLAG); // Flags; Loads a provider which supports reusable hash
	if (!NT_SUCCESS(status))
	{
		modState.state = MOD_CORRUPTED;
		return false;
	}

	// Obtain the length of the hash
	status = BCryptGetProperty(
		algorithmHandle, // Handle to a CNG object
		BCRYPT_HASH_LENGTH, // Property name (null terminated unicode string)
		(PBYTE)&hashLength, // Address of the output buffer which recieves the property value
		sizeof(hashLength), // Size of the buffer in bytes
		&resultLength, // Number of bytes that were copied into the buffer
		0); // Flags
	if (!NT_SUCCESS(status))
	{
		modState.state = MOD_CORRUPTED;
		return false;
	}

	// Create a hash handle
	status = BCryptCreateHash(
		algorithmHandle, // Handle to an algorithm provider
		&hashHandle, // A pointer to a hash handle - can be a hash or hmac object
		NULL, // Pointer to the buffer that recieves the hash/hmac object
		0, // Size of the buffer in bytes
		NULL, // A pointer to a key to use for the hash or MAC
		0, // Size of the key in bytes
		0); // Flags
	if (!NT_SUCCESS(status))
	{
		modState.state = MOD_CORRUPTED;
		return false;
	}

	// Hash archive content
	if (!fp.is_open())
	{
		spdlog::error("Unable to open archive.");
		modState.state = FAILED_READING_ARCHIVE;
		return false;
	}
	fp.seekg(0, fp.beg);
	while (fp.good())
	{
		fp.read(buffer.data(), bufferSize);
		std::streamsize bytesRead = fp.gcount();
		if (bytesRead > 0)
		{
			status = BCryptHashData(hashHandle, (PBYTE)buffer.data(), bytesRead, 0);
			if (!NT_SUCCESS(status))
			{
				modState.state = MOD_CORRUPTED;
				return false;
			}
		}
	}

	hash = std::vector<uint8_t>(hashLength);

	// Obtain the hash of the message(s) into the hash buffer
	status = BCryptFinishHash(
		hashHandle, // Handle to the hash or MAC object
		hash.data(), // A pointer to a buffer that receives the hash or MAC value
		hashLength, // Size of the buffer in bytes
		0); // Flags
	if (!NT_SUCCESS(status))
	{
		modState.state = MOD_CORRUPTED;
		return false;
	}

	// Convert hash to string using bytes raw values
	ss << std::hex << std::setfill('0');
	for (int i = 0; i < hashLength; i++)
	{
		ss << std::hex << std::setw(2) << static_cast<int>(hash.data()[i]);
	}

	spdlog::info("Expected checksum: {}", expectedChecksum.data());
	spdlog::info("Computed checksum: {}", ss.str());
	return expectedChecksum.compare(ss.str()) == 0;
}

bool ModDownloader::IsModAuthorized(std::string_view modName, std::string_view modVersion)
{
	if (strstr(GetCommandLineA(), VERIFICATION_FLAG))
	{
		spdlog::info("Bypassing mod verification due to flag set up.");
		return true;
	}

	if (!verifiedMods.contains(modName.data()))
	{
		return false;
	}

	std::unordered_map<std::string, VerifiedModVersion> versions = verifiedMods[modName.data()].versions;
	return versions.count(modVersion.data()) != 0;
}

int GetModArchiveSize(unzFile file, unz_global_info64 info)
{
	int totalSize = 0;

	for (int i = 0; i < info.number_entry; i++)
	{
		char zipFilename[256];
		unz_file_info64 fileInfo;
		unzGetCurrentFileInfo64(file, &fileInfo, zipFilename, sizeof(zipFilename), NULL, 0, NULL, 0);

		totalSize += fileInfo.uncompressed_size;

		if ((i + 1) < info.number_entry)
		{
			unzGoToNextFile(file);
		}
	}

	// Reset file pointer for archive extraction
	unzGoToFirstFile(file);

	return totalSize;
}

void ModDownloader::ExtractMod(fs::path modPath)
{
	unzFile file;
	std::string name;
	fs::path modDirectory;

	file = unzOpen(modPath.generic_string().c_str());
	ScopeGuard cleanup(
		[&]
		{
			if (unzClose(file) != MZ_OK)
			{
				spdlog::error("Failed closing mod archive after extraction.");
			}
		});

	if (file == NULL)
	{
		spdlog::error("Cannot open archive located at {}.", modPath.generic_string());
		modState.state = FAILED_READING_ARCHIVE;
		return;
	}

	unz_global_info64 gi;
	int status;
	status = unzGetGlobalInfo64(file, &gi);
	if (status != UNZ_OK)
	{
		spdlog::error("Failed getting information from archive (error code: {})", status);
		modState.state = FAILED_READING_ARCHIVE;
		return;
	}

	// Update state
	modState.state = EXTRACTING;
	modState.total = GetModArchiveSize(file, gi);
	modState.progress = 0;

	// Mod directory name (removing the ".zip" fom the archive name)
	name = modPath.filename().string();
	name = name.substr(0, name.length() - 4);
	modDirectory = GetRemoteModFolderPath() / name;

	for (int i = 0; i < gi.number_entry; i++)
	{
		char zipFilename[256];
		unz_file_info64 fileInfo;
		status = unzGetCurrentFileInfo64(file, &fileInfo, zipFilename, sizeof(zipFilename), NULL, 0, NULL, 0);

		// Extract file
		{
			std::error_code ec;
			fs::path fileDestination = modDirectory / zipFilename;
			spdlog::info("=> {}", fileDestination.generic_string());

			// Create parent directory if needed
			if (!std::filesystem::exists(fileDestination.parent_path()))
			{
				spdlog::info("Parent directory does not exist, creating it.", fileDestination.generic_string());
				if (!std::filesystem::create_directories(fileDestination.parent_path(), ec) && ec.value() != 0)
				{
					spdlog::error("Parent directory ({}) creation failed.", fileDestination.parent_path().generic_string());
					modState.state = FAILED_WRITING_TO_DISK;
					return;
				}
			}

			// If current file is a directory, create directory...
			if (fileDestination.generic_string().back() == '/')
			{
				// Create directory
				if (!std::filesystem::create_directory(fileDestination, ec) && ec.value() != 0)
				{
					spdlog::error("Directory creation failed: {}", ec.message());
					modState.state = FAILED_WRITING_TO_DISK;
					return;
				}
			}
			// ...else create file
			else
			{
				// Ensure file is in zip archive
				if (unzLocateFile(file, zipFilename, 0) != UNZ_OK)
				{
					spdlog::error("File \"{}\" was not found in archive.", zipFilename);
					modState.state = FAILED_READING_ARCHIVE;
					return;
				}

				// Create file
				const int bufferSize = 8192;
				void* buffer;
				int err = UNZ_OK;
				FILE* fout = NULL;

				// Open zip file to prepare its extraction
				status = unzOpenCurrentFile(file);
				if (status != UNZ_OK)
				{
					spdlog::error("Could not open file {} from archive.", zipFilename);
					modState.state = FAILED_READING_ARCHIVE;
					return;
				}

				// Create destination file
				fout = fopen(fileDestination.generic_string().c_str(), "wb");
				if (fout == NULL)
				{
					spdlog::error("Failed creating destination file.");
					modState.state = FAILED_WRITING_TO_DISK;
					return;
				}

				// Allocate memory for buffer
				buffer = (void*)malloc(bufferSize);
				if (buffer == NULL)
				{
					spdlog::error("Error while allocating memory.");
					modState.state = FAILED_WRITING_TO_DISK;
					return;
				}

				// Extract file to destination
				do
				{
					err = unzReadCurrentFile(file, buffer, bufferSize);
					if (err < 0)
					{
						spdlog::error("error {} with zipfile in unzReadCurrentFile", err);
						break;
					}
					if (err > 0)
					{
						if (fwrite(buffer, (unsigned)err, 1, fout) != 1)
						{
							spdlog::error("error in writing extracted file\n");
							err = UNZ_ERRNO;
							break;
						}
					}

					// Update extraction stats
					modState.progress += bufferSize;
					modState.ratio = roundf(static_cast<float>(modState.progress) / modState.total * 100);
				} while (err > 0);

				if (err != UNZ_OK)
				{
					spdlog::error("An error occurred during file extraction (code: {})", err);
					modState.state = FAILED_WRITING_TO_DISK;
					return;
				}
				err = unzCloseCurrentFile(file);
				if (err != UNZ_OK)
				{
					spdlog::error("error {} with zipfile in unzCloseCurrentFile", err);
				}

				// Cleanup
				if (fout)
					fclose(fout);
			}
		}

		// Go to next file
		if ((i + 1) < gi.number_entry)
		{
			status = unzGoToNextFile(file);
			if (status != UNZ_OK)
			{
				spdlog::error("Error while browsing archive files (error code: {}).", status);
				return;
			}
		}
	}
}

void ModDownloader::DownloadMod(std::string modName, std::string modVersion)
{
	// Check if mod can be auto-downloaded
	if (!IsModAuthorized(std::string_view(modName), std::string_view(modVersion)))
	{
		spdlog::warn("Tried to download a mod that is not verified, aborting.");
		return;
	}

	std::thread requestThread(
		[this, modName, modVersion]()
		{
			fs::path archiveLocation;

			ScopeGuard cleanup(
				[&]
				{
					try
					{
						remove(archiveLocation);
					}
					catch (const std::exception& a)
					{
						spdlog::error("Error while removing downloaded archive: {}", a.what());
					}

					modState.state = DONE;
					spdlog::info("Done downloading {}.", modName);
				});

			// Download mod archive
			std::string expectedHash = verifiedMods[modName].versions[modVersion].checksum;
			std::optional<fs::path> fetchingResult = FetchModFromDistantStore(std::string_view(modName), std::string_view(modVersion));
			if (!fetchingResult.has_value())
			{
				spdlog::error("Something went wrong while fetching archive, aborting.");
				modState.state = MOD_FETCHING_FAILED;
				return;
			}
			archiveLocation = fetchingResult.value();
			if (!IsModLegit(archiveLocation, std::string_view(expectedHash)))
			{
				spdlog::warn("Archive hash does not match expected checksum, aborting.");
				modState.state = MOD_CORRUPTED;
				return;
			}

			// Extract downloaded mod archive
			ExtractMod(archiveLocation);
		});

	requestThread.detach();
}

ON_DLL_LOAD_RELIESON("engine.dll", ModDownloader, (ConCommand), (CModule module))
{
	g_pModDownloader = new ModDownloader();
	g_pModDownloader->FetchModsListFromAPI();
}

ADD_SQFUNC(
	"bool", NSIsModDownloadable, "string name, string version", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
{
	g_pSquirrel<context>->newarray(sqvm, 0);

	const SQChar* modName = g_pSquirrel<context>->getstring(sqvm, 1);
	const SQChar* modVersion = g_pSquirrel<context>->getstring(sqvm, 2);

	bool result = g_pModDownloader->IsModAuthorized(modName, modVersion);
	g_pSquirrel<context>->pushbool(sqvm, result);

	return SQRESULT_NOTNULL;
}

ADD_SQFUNC("void", NSDownloadMod, "string name, string version", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
{
	const SQChar* modName = g_pSquirrel<context>->getstring(sqvm, 1);
	const SQChar* modVersion = g_pSquirrel<context>->getstring(sqvm, 2);
	g_pModDownloader->DownloadMod(modName, modVersion);

	return SQRESULT_NOTNULL;
}

ADD_SQFUNC("ModInstallState", NSGetModInstallState, "", "", ScriptContext::SERVER | ScriptContext::CLIENT | ScriptContext::UI)
{
	g_pSquirrel<context>->pushnewstructinstance(sqvm, 4);

	// state
	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.state);
	g_pSquirrel<context>->sealstructslot(sqvm, 0);

	// progress
	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.progress);
	g_pSquirrel<context>->sealstructslot(sqvm, 1);

	// total
	g_pSquirrel<context>->pushinteger(sqvm, g_pModDownloader->modState.total);
	g_pSquirrel<context>->sealstructslot(sqvm, 2);

	// ratio
	g_pSquirrel<context>->pushfloat(sqvm, g_pModDownloader->modState.ratio);
	g_pSquirrel<context>->sealstructslot(sqvm, 3);

	return SQRESULT_NOTNULL;
}