src/platform/Darwin/KeyValueStoreManagerImpl.mm - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2021 Project CHIP Authors
  *    All rights reserved.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
  *    You may obtain a copy of the License at
  *
  *        http://www.apache.org/licenses/LICENSE-2.0
  *
  *    Unless required by applicable law or agreed to in writing, software
  *    distributed under the License is distributed on an "AS IS" BASIS,
  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */

 /**
  *    @file
  *          Platform-specific key value storage implementation for Darwin
  */

 #if !__has_feature(objc_arc)
 #error This file must be compiled with ARC. Use -fobjc-arc flag (or convert project to ARC).
 #endif

 #include <platform/KeyValueStoreManager.h>

 #include <algorithm>

 #include <lib/support/CodeUtils.h>

 #import <CoreData/CoreData.h>
 #import <CoreFoundation/CoreFoundation.h>

 #ifndef CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
 #define CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING 0
 #endif // CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING

 @interface KeyValueItem : NSManagedObject

 @property (nonatomic, retain) NSString * key;
 @property (nonatomic, retain) NSData * value;

 @end

 @implementation KeyValueItem

 @dynamic key;
 @dynamic value;

 - (instancetype)initWithContext:(nonnull NSManagedObjectContext *)context key:(nonnull NSString *)key value:(nonnull NSData *)value
 {
     if (self = [super initWithContext:context]) {
         self.key = key;
         self.value = value;
     }
     return self;
 }

 @end

 namespace chip {
 namespace DeviceLayer {
     namespace PersistedStorage {
         namespace {

             NSManagedObjectContext * gContext = nullptr;

             NSManagedObjectModel * CreateManagedObjectModel()
             {
                 NSManagedObjectModel * model = [[NSManagedObjectModel alloc] init];

                 // create the entity
                 NSEntityDescription * entity = [[NSEntityDescription alloc] init];
                 [entity setName:@"KeyValue"];
                 [entity setManagedObjectClassName:@"KeyValueItem"];

                 // create the attributes
                 NSMutableArray * properties = [NSMutableArray array];

                 NSAttributeDescription * keyAttribute = [[NSAttributeDescription alloc] init];
                 [keyAttribute setName:@"key"];
                 [keyAttribute setAttributeType:NSStringAttributeType];
                 [keyAttribute setOptional:NO];
                 [properties addObject:keyAttribute];

                 NSAttributeDescription * valueAttribute = [[NSAttributeDescription alloc] init];
                 [valueAttribute setName:@"value"];
                 [valueAttribute setAttributeType:NSBinaryDataAttributeType];
                 [valueAttribute setOptional:NO];
                 [properties addObject:valueAttribute];

                 NSFetchIndexElementDescription * elementIndex =
                     [[NSFetchIndexElementDescription alloc] initWithProperty:keyAttribute
                                                                collationType:NSFetchIndexElementTypeBinary];
                 elementIndex.ascending = true;

                 NSFetchIndexDescription * keyIndexDescription =
                     [[NSFetchIndexDescription alloc] initWithName:@"kv_item_key"
                                                          elements:[[NSArray alloc] initWithObjects:elementIndex, nil]];

                 // add attributes to entity
                 [entity setProperties:properties];
                 [entity setIndexes:[[NSArray alloc] initWithObjects:keyIndexDescription, nil]];

                 // add entity to model
                 [model setEntities:[NSArray arrayWithObject:entity]];

                 return model;
             }

             KeyValueItem * FindItemForKey(NSString * key, NSError ** error, BOOL returnsData)
             {
                 NSFetchRequest * request = [[NSFetchRequest alloc] initWithEntityName:@"KeyValue"];
                 if (returnsData) {
                     [request setReturnsObjectsAsFaults:NO];
                 }
                 request.predicate = [NSPredicate predicateWithFormat:@"key = %@", key];

                 __block NSError * fetchError = nil;
                 __block NSArray * result;
                 [gContext performBlockAndWait:^{
                     result = [gContext executeFetchRequest:request error:&fetchError];
                 }];

                 if (error != nil) {
                     *error = fetchError;
                 }

                 if (result == nil) {
                     return nullptr;
                 }

                 if (result.count == 0) {
                     return nullptr;
                 }
                 return (KeyValueItem *) [result objectAtIndex:0];
             }

             KeyValueItem * FindItemForKey(NSString * key, NSError ** error) { return FindItemForKey(key, error, false); }

         } // namespace

         KeyValueStoreManagerImpl KeyValueStoreManagerImpl::sInstance;

         CHIP_ERROR KeyValueStoreManagerImpl::Init(const char * fileName)
         {
             @autoreleasepool {
                 if (mInitialized) {
                     return CHIP_NO_ERROR;
                 }

                 ReturnErrorCodeIf(gContext != nullptr, CHIP_ERROR_INCORRECT_STATE);
                 ReturnErrorCodeIf(fileName == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
                 ReturnErrorCodeIf(fileName[0] == '\0', CHIP_ERROR_INVALID_ARGUMENT);

                 NSURL * url = nullptr;
                 NSString * filepath = [NSString stringWithUTF8String:fileName];
                 ReturnErrorCodeIf(filepath == nil, CHIP_ERROR_INVALID_ARGUMENT);

                 // relative paths are relative to Documents folder
                 if (![filepath hasPrefix:@"/"]) {
                     NSURL * documentsDirectory = [NSFileManager.defaultManager URLForDirectory:NSDocumentDirectory
                                                                                       inDomain:NSUserDomainMask
                                                                              appropriateForURL:nil
                                                                                         create:YES
                                                                                          error:nil];
                     if (documentsDirectory == nullptr) {
                         ChipLogError(DeviceLayer, "Failed to get documents directory.");
                         return CHIP_ERROR_INTERNAL;
                     }
                     ChipLogProgress(
                         DeviceLayer, "Found user documents directory: %s", [[documentsDirectory absoluteString] UTF8String]);

                     url = [NSURL URLWithString:filepath relativeToURL:documentsDirectory];
                 } else {
                     url = [NSURL fileURLWithPath:filepath];
                 }
                 ReturnErrorCodeIf(url == nullptr, CHIP_ERROR_NO_MEMORY);

                 ChipLogProgress(DeviceLayer, "KVS will be written to: %s", [[url absoluteString] UTF8String]);

                 NSManagedObjectModel * model = CreateManagedObjectModel();
                 ReturnErrorCodeIf(model == nullptr, CHIP_ERROR_NO_MEMORY);

                 // setup persistent store coordinator

                 NSPersistentStoreCoordinator * coordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];

                 NSError * error = nil;
                 if (![coordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:url options:nil error:&error]) {
                     ChipLogError(DeviceLayer, "Invalid store. Attempting to clear: %s", error.localizedDescription.UTF8String);
                     if (![[NSFileManager defaultManager] removeItemAtURL:url error:&error]) {
                         ChipLogError(DeviceLayer, "Failed to delete item: %s", error.localizedDescription.UTF8String);
                     }

                     if (![coordinator addPersistentStoreWithType:NSSQLiteStoreType
                                                    configuration:nil
                                                              URL:url
                                                          options:nil
                                                            error:&error]) {
                         ChipLogError(DeviceLayer, "Failed to initialize clear KVS storage: %s", error.localizedDescription.UTF8String);
                         chipDie();
                     }
                 }

                 // create Managed Object context
                 gContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
                 [gContext setMergePolicy:NSMergeByPropertyObjectTrumpMergePolicy];
                 [gContext setPersistentStoreCoordinator:coordinator];

                 mInitialized = true;
                 return CHIP_NO_ERROR;
             } // @autoreleasepool
         }

         CHIP_ERROR KeyValueStoreManagerImpl::_Get(
             const char * key, void * value, size_t value_size, size_t * read_bytes_size, size_t offset)
         {
             @autoreleasepool {
                 ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
                 ReturnErrorCodeIf(offset != 0, CHIP_ERROR_INVALID_ARGUMENT);
                 ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

                 KeyValueItem * item = FindItemForKey([[NSString alloc] initWithUTF8String:key], nil, true);
                 if (!item) {
                     return CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND;
                 }

                 __block NSData * itemValue = nil;
                 // can only access this object on the managed queue
                 [gContext performBlockAndWait:^{
                     itemValue = item.value;
                 }];

                 if (read_bytes_size != nullptr) {
                     *read_bytes_size = itemValue.length;
                 }

                 if (value != nullptr) {
                     memcpy(value, itemValue.bytes, std::min<size_t>((itemValue.length), value_size));
 #if CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
                     fprintf(stderr, "GETTING VALUE FOR: '%s': ", key);
                     for (size_t i = 0; i < std::min<size_t>((itemValue.length), value_size); ++i) {
                         fprintf(stderr, "%02x ", static_cast<uint8_t *>(value)[i]);
                     }
                     fprintf(stderr, "\n");
 #endif
                 }

                 if (itemValue.length > value_size) {
                     return CHIP_ERROR_BUFFER_TOO_SMALL;
                 }

                 return CHIP_NO_ERROR;
             } // @autoreleasepool
         }

         CHIP_ERROR KeyValueStoreManagerImpl::_Delete(const char * key)
         {
             @autoreleasepool {
                 ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
                 ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

                 KeyValueItem * item = FindItemForKey([[NSString alloc] initWithUTF8String:key], nil);
                 if (!item) {
                     return CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND;
                 }

                 __block BOOL success = NO;
                 __block NSError * error = nil;
                 [gContext performBlockAndWait:^{
                     [gContext deleteObject:item];
                     success = [gContext save:&error];
                 }];

                 if (!success) {
                     ChipLogError(DeviceLayer, "Error saving context: %s", error.localizedDescription.UTF8String);
                     return CHIP_ERROR_PERSISTED_STORAGE_FAILED;
                 }

                 return CHIP_NO_ERROR;
             } // @autoreleasepool
         }

         CHIP_ERROR KeyValueStoreManagerImpl::_Put(const char * key, const void * value, size_t value_size)
         {
             @autoreleasepool {
                 ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
                 ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

                 NSData * data = [[NSData alloc] initWithBytes:value length:value_size];

                 NSString * itemKey = [[NSString alloc] initWithUTF8String:key];
                 ReturnErrorCodeIf(itemKey == nil, CHIP_ERROR_INVALID_ARGUMENT);

                 KeyValueItem * item = FindItemForKey(itemKey, nil);
                 if (!item) {
                     [gContext performBlockAndWait:^{
                         [gContext insertObject:[[KeyValueItem alloc] initWithContext:gContext key:itemKey value:data]];
                     }];
                 } else {
                     [gContext performBlockAndWait:^{
                         item.value = data;
                     }];
                 }

                 __block BOOL success = NO;
                 __block NSError * error = nil;
                 [gContext performBlockAndWait:^{
                     success = [gContext save:&error];
                 }];

                 if (!success) {
                     ChipLogError(DeviceLayer, "Error saving context: %s", error.localizedDescription.UTF8String);
                     return CHIP_ERROR_PERSISTED_STORAGE_FAILED;
                 }

 #if CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
                 fprintf(stderr, "PUT VALUE FOR: '%s': ", key);
                 for (size_t i = 0; i < value_size; ++i) {
                     fprintf(stderr, "%02x ", static_cast<const uint8_t *>(value)[i]);
                 }
                 fprintf(stderr, "\n");
 #endif

                 return CHIP_NO_ERROR;
             } // @autoreleasepool
         }

     } // namespace PersistedStorage
 } // namespace DeviceLayer
 } // namespace chip
	/*
	*
	* Copyright (c) 2021 Project CHIP Authors
	* All rights reserved.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/**
	* @file
	* Platform-specific key value storage implementation for Darwin
	*/

	#if !__has_feature(objc_arc)
	#error This file must be compiled with ARC. Use -fobjc-arc flag (or convert project to ARC).
	#endif

	#include <platform/KeyValueStoreManager.h>

	#include <algorithm>

	#include <lib/support/CodeUtils.h>

	#import <CoreData/CoreData.h>
	#import <CoreFoundation/CoreFoundation.h>

	#ifndef CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
	#define CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING 0
	#endif // CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING

	@interface KeyValueItem : NSManagedObject

	@property (nonatomic, retain) NSString * key;
	@property (nonatomic, retain) NSData * value;

	@end

	@implementation KeyValueItem

	@dynamic key;
	@dynamic value;

	- (instancetype)initWithContext:(nonnull NSManagedObjectContext )context key:(nonnull NSString )key value:(nonnull NSData *)value
	{
	if (self = [super initWithContext:context]) {
	self.key = key;
	self.value = value;
	}
	return self;
	}

	@end

	namespace chip {
	namespace DeviceLayer {
	namespace PersistedStorage {
	namespace {

	NSManagedObjectContext * gContext = nullptr;

	NSManagedObjectModel * CreateManagedObjectModel()
	{
	NSManagedObjectModel * model = [[NSManagedObjectModel alloc] init];

	// create the entity
	NSEntityDescription * entity = [[NSEntityDescription alloc] init];
	[entity setName:@"KeyValue"];
	[entity setManagedObjectClassName:@"KeyValueItem"];

	// create the attributes
	NSMutableArray * properties = [NSMutableArray array];

	NSAttributeDescription * keyAttribute = [[NSAttributeDescription alloc] init];
	[keyAttribute setName:@"key"];
	[keyAttribute setAttributeType:NSStringAttributeType];
	[keyAttribute setOptional:NO];
	[properties addObject:keyAttribute];

	NSAttributeDescription * valueAttribute = [[NSAttributeDescription alloc] init];
	[valueAttribute setName:@"value"];
	[valueAttribute setAttributeType:NSBinaryDataAttributeType];
	[valueAttribute setOptional:NO];
	[properties addObject:valueAttribute];

	NSFetchIndexElementDescription * elementIndex =
	[[NSFetchIndexElementDescription alloc] initWithProperty:keyAttribute
	collationType:NSFetchIndexElementTypeBinary];
	elementIndex.ascending = true;

	NSFetchIndexDescription * keyIndexDescription =
	[[NSFetchIndexDescription alloc] initWithName:@"kv_item_key"
	elements:[[NSArray alloc] initWithObjects:elementIndex, nil]];

	// add attributes to entity
	[entity setProperties:properties];
	[entity setIndexes:[[NSArray alloc] initWithObjects:keyIndexDescription, nil]];

	// add entity to model
	[model setEntities:[NSArray arrayWithObject:entity]];

	return model;
	}

	KeyValueItem * FindItemForKey(NSString * key, NSError ** error, BOOL returnsData)
	{
	NSFetchRequest * request = [[NSFetchRequest alloc] initWithEntityName:@"KeyValue"];
	if (returnsData) {
	[request setReturnsObjectsAsFaults:NO];
	}
	request.predicate = [NSPredicate predicateWithFormat:@"key = %@", key];

	__block NSError * fetchError = nil;
	__block NSArray * result;
	[gContext performBlockAndWait:^{
	result = [gContext executeFetchRequest:request error:&fetchError];
	}];

	if (error != nil) {
	*error = fetchError;
	}

	if (result == nil) {
	return nullptr;
	}

	if (result.count == 0) {
	return nullptr;
	}
	return (KeyValueItem *) [result objectAtIndex:0];
	}

	KeyValueItem * FindItemForKey(NSString * key, NSError ** error) { return FindItemForKey(key, error, false); }

	} // namespace

	KeyValueStoreManagerImpl KeyValueStoreManagerImpl::sInstance;

	CHIP_ERROR KeyValueStoreManagerImpl::Init(const char * fileName)
	{
	@autoreleasepool {
	if (mInitialized) {
	return CHIP_NO_ERROR;
	}

	ReturnErrorCodeIf(gContext != nullptr, CHIP_ERROR_INCORRECT_STATE);
	ReturnErrorCodeIf(fileName == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	ReturnErrorCodeIf(fileName[0] == '\0', CHIP_ERROR_INVALID_ARGUMENT);

	NSURL * url = nullptr;
	NSString * filepath = [NSString stringWithUTF8String:fileName];
	ReturnErrorCodeIf(filepath == nil, CHIP_ERROR_INVALID_ARGUMENT);

	// relative paths are relative to Documents folder
	if (![filepath hasPrefix:@"/"]) {
	NSURL * documentsDirectory = [NSFileManager.defaultManager URLForDirectory:NSDocumentDirectory
	inDomain:NSUserDomainMask
	appropriateForURL:nil
	create:YES
	error:nil];
	if (documentsDirectory == nullptr) {
	ChipLogError(DeviceLayer, "Failed to get documents directory.");
	return CHIP_ERROR_INTERNAL;
	}
	ChipLogProgress(
	DeviceLayer, "Found user documents directory: %s", [[documentsDirectory absoluteString] UTF8String]);

	url = [NSURL URLWithString:filepath relativeToURL:documentsDirectory];
	} else {
	url = [NSURL fileURLWithPath:filepath];
	}
	ReturnErrorCodeIf(url == nullptr, CHIP_ERROR_NO_MEMORY);

	ChipLogProgress(DeviceLayer, "KVS will be written to: %s", [[url absoluteString] UTF8String]);

	NSManagedObjectModel * model = CreateManagedObjectModel();
	ReturnErrorCodeIf(model == nullptr, CHIP_ERROR_NO_MEMORY);

	// setup persistent store coordinator

	NSPersistentStoreCoordinator * coordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];

	NSError * error = nil;
	if (![coordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:url options:nil error:&error]) {
	ChipLogError(DeviceLayer, "Invalid store. Attempting to clear: %s", error.localizedDescription.UTF8String);
	if (![[NSFileManager defaultManager] removeItemAtURL:url error:&error]) {
	ChipLogError(DeviceLayer, "Failed to delete item: %s", error.localizedDescription.UTF8String);
	}

	if (![coordinator addPersistentStoreWithType:NSSQLiteStoreType
	configuration:nil
	URL:url
	options:nil
	error:&error]) {
	ChipLogError(DeviceLayer, "Failed to initialize clear KVS storage: %s", error.localizedDescription.UTF8String);
	chipDie();
	}
	}

	// create Managed Object context
	gContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
	[gContext setMergePolicy:NSMergeByPropertyObjectTrumpMergePolicy];
	[gContext setPersistentStoreCoordinator:coordinator];

	mInitialized = true;
	return CHIP_NO_ERROR;
	} // @autoreleasepool
	}

	CHIP_ERROR KeyValueStoreManagerImpl::_Get(
	const char * key, void * value, size_t value_size, size_t * read_bytes_size, size_t offset)
	{
	@autoreleasepool {
	ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	ReturnErrorCodeIf(offset != 0, CHIP_ERROR_INVALID_ARGUMENT);
	ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

	KeyValueItem * item = FindItemForKey([[NSString alloc] initWithUTF8String:key], nil, true);
	if (!item) {
	return CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND;
	}

	__block NSData * itemValue = nil;
	// can only access this object on the managed queue
	[gContext performBlockAndWait:^{
	itemValue = item.value;
	}];

	if (read_bytes_size != nullptr) {
	*read_bytes_size = itemValue.length;
	}

	if (value != nullptr) {
	memcpy(value, itemValue.bytes, std::min<size_t>((itemValue.length), value_size));
	#if CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
	fprintf(stderr, "GETTING VALUE FOR: '%s': ", key);
	for (size_t i = 0; i < std::min<size_t>((itemValue.length), value_size); ++i) {
	fprintf(stderr, "%02x ", static_cast<uint8_t *>(value)[i]);
	}
	fprintf(stderr, "\n");
	#endif
	}

	if (itemValue.length > value_size) {
	return CHIP_ERROR_BUFFER_TOO_SMALL;
	}

	return CHIP_NO_ERROR;
	} // @autoreleasepool
	}

	CHIP_ERROR KeyValueStoreManagerImpl::_Delete(const char * key)
	{
	@autoreleasepool {
	ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

	KeyValueItem * item = FindItemForKey([[NSString alloc] initWithUTF8String:key], nil);
	if (!item) {
	return CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND;
	}

	__block BOOL success = NO;
	__block NSError * error = nil;
	[gContext performBlockAndWait:^{
	[gContext deleteObject:item];
	success = [gContext save:&error];
	}];

	if (!success) {
	ChipLogError(DeviceLayer, "Error saving context: %s", error.localizedDescription.UTF8String);
	return CHIP_ERROR_PERSISTED_STORAGE_FAILED;
	}

	return CHIP_NO_ERROR;
	} // @autoreleasepool
	}

	CHIP_ERROR KeyValueStoreManagerImpl::_Put(const char * key, const void * value, size_t value_size)
	{
	@autoreleasepool {
	ReturnErrorCodeIf(key == nullptr, CHIP_ERROR_INVALID_ARGUMENT);
	ReturnErrorCodeIf(gContext == nullptr, CHIP_ERROR_UNINITIALIZED);

	NSData * data = [[NSData alloc] initWithBytes:value length:value_size];

	NSString * itemKey = [[NSString alloc] initWithUTF8String:key];
	ReturnErrorCodeIf(itemKey == nil, CHIP_ERROR_INVALID_ARGUMENT);

	KeyValueItem * item = FindItemForKey(itemKey, nil);
	if (!item) {
	[gContext performBlockAndWait:^{
	[gContext insertObject:[[KeyValueItem alloc] initWithContext:gContext key:itemKey value:data]];
	}];
	} else {
	[gContext performBlockAndWait:^{
	item.value = data;
	}];
	}

	__block BOOL success = NO;
	__block NSError * error = nil;
	[gContext performBlockAndWait:^{
	success = [gContext save:&error];
	}];

	if (!success) {
	ChipLogError(DeviceLayer, "Error saving context: %s", error.localizedDescription.UTF8String);
	return CHIP_ERROR_PERSISTED_STORAGE_FAILED;
	}

	#if CHIP_CONFIG_DARWIN_STORAGE_VERBOSE_LOGGING
	fprintf(stderr, "PUT VALUE FOR: '%s': ", key);
	for (size_t i = 0; i < value_size; ++i) {
	fprintf(stderr, "%02x ", static_cast<const uint8_t *>(value)[i]);
	}
	fprintf(stderr, "\n");
	#endif

	return CHIP_NO_ERROR;
	} // @autoreleasepool
	}

	} // namespace PersistedStorage
	} // namespace DeviceLayer
	} // namespace chip