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Diffstat (limited to 'Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m')
| -rw-r--r-- | Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m | 834 |
1 files changed, 834 insertions, 0 deletions
diff --git a/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m new file mode 100644 index 00000000..4968266d --- /dev/null +++ b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection.m @@ -0,0 +1,834 @@ +// +// $Id$ +// +// SPMySQLConnection.m +// SPMySQLFramework +// +// Created by Rowan Beentje (rowan.beent.je) on January 8, 2012 +// Copyright (c) 2012 Rowan Beentje. All rights reserved. +// +// Permission is hereby granted, free of charge, to any person +// obtaining a copy of this software and associated documentation +// files (the "Software"), to deal in the Software without +// restriction, including without limitation the rights to use, +// copy, modify, merge, publish, distribute, sublicense, and/or sell +// copies of the Software, and to permit persons to whom the +// Software is furnished to do so, subject to the following +// conditions: +// +// The above copyright notice and this permission notice shall be +// included in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES +// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT +// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, +// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR +// OTHER DEALINGS IN THE SOFTWARE. +// +// More info at <http://code.google.com/p/sequel-pro/> + +#import "SPMySQL Private APIs.h" +#include <mach/mach_time.h> +#include <pthread.h> +#include <SystemConfiguration/SCNetworkReachability.h> + + +#pragma mark Class constants + +// The default connection options for MySQL connections +const NSUInteger SPMySQLConnectionOptions = + CLIENT_COMPRESS | // Enable protocol compression - almost always a win + CLIENT_INTERACTIVE | // Mark ourselves as an interactive client + CLIENT_MULTI_RESULTS; // Multiple result support (very basic, but present) + +// List of permissible ciphers to use for SSL connections +const char *SPMySQLSSLPermissibleCiphers = "DHE-RSA-AES256-SHA:AES256-SHA:DHE-RSA-AES128-SHA:AES128-SHA:AES256-RMD:AES128-RMD:DES-CBC3-RMD:DHE-RSA-AES256-RMD:DHE-RSA-AES128-RMD:DHE-RSA-DES-CBC3-RMD:RC4-SHA:RC4-MD5:DES-CBC3-SHA:DES-CBC-SHA:EDH-RSA-DES-CBC3-SHA:EDH-RSA-DES-CBC-SHA"; + + +@implementation SPMySQLConnection + +#pragma mark - +#pragma mark Synthesized properties + +@synthesize delegate; +@synthesize proxy; +@synthesize host; +@synthesize username; +@synthesize password; +@synthesize port; +@synthesize useSocket; +@synthesize socketPath; +@synthesize useSSL; +@synthesize sslKeyFilePath; +@synthesize sslCertificatePath; +@synthesize sslCACertificatePath; +@synthesize timeout; +@synthesize useKeepAlive; +@synthesize keepAliveInterval; +@synthesize mysqlConnectionThreadId; +@synthesize retryQueriesOnConnectionFailure; +@synthesize delegateQueryLogging; + +#pragma mark - +#pragma mark Initialisation and teardown + +/** + * Initialise the SPMySQLConnection object, setting up class defaults. + * + * Typically initialisation would be followed by setting the connection details + * and then calling -connect. + */ +- (id)init +{ + if ((self = [super init])) { + mySQLConnection = NULL; + state = SPMySQLDisconnected; + userTriggeredDisconnect = NO; + isReconnecting = NO; + mysqlConnectionThreadId = 0; + initialConnectTime = 0; + + port = 3306; + + // Default to socket connections if no other details have been provided + useSocket = YES; + + // Start with no proxy + proxy = nil; + proxyStateChangeNotificationsIgnored = NO; + + // Start with no selected database + database = nil; + + // Set a timeout of 30 seconds, with keepalive on and acting every sixty seconds + timeout = 30; + useKeepAlive = YES; + keepAliveInterval = 60; + keepAlivePingFailures = 0; + lastKeepAliveTime = 0; + keepAlivePingThread = NULL; + keepAlivePingThreadActive = NO; + keepAliveLastPingSuccess = NO; + keepAliveLastPingBlocked = NO; + + // Set up default encoding variables + encoding = [[NSString alloc] initWithString:@"utf8"]; + stringEncoding = NSUTF8StringEncoding; + encodingUsesLatin1Transport = NO; + previousEncoding = nil; + previousEncodingUsesLatin1Transport = NO; + + // Initialise default delegate settings + delegateSupportsWillQueryString = NO; + delegateSupportsConnectionLost = NO; + delegateQueryLogging = YES; + + // Delegate disconnection decisions + reconnectionRetryAttempts = 0; + lastDelegateDecisionForLostConnection = SPMySQLConnectionLostDisconnect; + delegateDecisionLock = [[NSLock alloc] init]; + + // Set up the connection lock + connectionLock = [[NSConditionLock alloc] initWithCondition:SPMySQLConnectionIdle]; + [connectionLock setName:@"SPMySQLConnection query lock"]; + + // Ensure the server detail records are initialised + serverVersionString = nil; + + // Start with a blank error state + queryErrorID = 0; + queryErrorMessage = nil; + + // Start with empty cancellation details + lastQueryWasCancelled = NO; + lastQueryWasCancelledUsingReconnect = NO; + + // Empty or reset the timing variables + lastConnectionUsedTime = 0; + lastQueryExecutionTime = 0; + + // Default to editable query size of 1MB + maxQuerySize = 1048576; + maxQuerySizeIsEditable = YES; + maxQuerySizeEditabilityChecked = NO; + queryActionShouldRestoreMaxQuerySize = NSNotFound; + + // Default to allowing queries to be automatically retried if the connection drops + // while running them + retryQueriesOnConnectionFailure = YES; + + // Start the ping keepalive timer + if ([NSThread isMainThread]) { + [self _initKeepAlivePingTimer]; + } else { + [self performSelectorOnMainThread:@selector(_initKeepAlivePingTimer) withObject:nil waitUntilDone:YES]; + } + } + + return self; +} + +/** + * Object deallocation. + */ +- (void) dealloc +{ + userTriggeredDisconnect = YES; + + // Unset the delegate + [self setDelegate:nil]; + + // Disconnect if appropriate (which should also disconnect any proxy) + [self disconnect]; + + // Clean up the connection proxy, if any + if (proxy) { + [proxy setConnectionStateChangeSelector:NULL delegate:nil]; + [proxy release]; + } + + // Ensure the query lock is unlocked, thereafter setting to nil in case of pending calls + if ([connectionLock condition] != SPMySQLConnectionIdle) { + [self _unlockConnection]; + } + [connectionLock release], connectionLock = nil; + + [encoding dealloc]; + if (previousEncoding) [previousEncoding release], previousEncoding = nil; + + if (database) [database release], database = nil; + if (serverVersionString) [serverVersionString release], serverVersionString = nil; + if (queryErrorMessage) [queryErrorMessage release], queryErrorMessage = nil; + [keepAliveTimer invalidate]; + [keepAliveTimer release]; + [delegateDecisionLock release]; + + [NSObject cancelPreviousPerformRequestsWithTarget:self]; + + [super dealloc]; +} + +#pragma mark - +#pragma mark Connection and disconnection + +/** + * Trigger a connection to the specified host, if any, using any connection details + * that have been set. + * Returns whether the connection was successful. + */ +- (BOOL)connect +{ + + // If a connection is already active in some form, throw an exception + if (state != SPMySQLDisconnected) { + [NSException raise:NSInternalInconsistencyException format:@"Attempted to connect a connection that is not disconnected."]; + return NO; + } + state = SPMySQLConnecting; + + // Lock the connection for safety + [self _lockConnection]; + + // Attempt the connection + mySQLConnection = [self _makeRawMySQLConnectionWithEncoding:encoding isMasterConnection:YES]; + + // If the connection failed, reset state and return + if (!mySQLConnection) { + [self _unlockConnection]; + state = SPMySQLDisconnected; + return NO; + } + + // Successfully connected - record connected state and reset tracking variables + state = SPMySQLConnected; + userTriggeredDisconnect = NO; + reconnectionRetryAttempts = 0; + initialConnectTime = mach_absolute_time(); + mysqlConnectionThreadId = mySQLConnection->thread_id; + lastConnectionUsedTime = 0; + + // Update SSL state + connectedWithSSL = NO; + if (useSSL) connectedWithSSL = (mysql_get_ssl_cipher(mySQLConnection))?YES:NO; + if (useSSL && !connectedWithSSL) { + if ([delegate respondsToSelector:@selector(connectionFellBackToNonSSL:)]) { + [delegate connectionFellBackToNonSSL:self]; + } + } + + // Reset keepalive variables + lastKeepAliveTime = 0; + keepAlivePingFailures = 0; + + // Clear the connection error record + [self _updateLastErrorID:NSNotFound]; + [self _updateLastErrorMessage:nil]; + + // Unlock the connection + [self _unlockConnection]; + + // Update connection variables to be in sync with the server state. As this performs + // a query, ensure the connection is still up afterwards (!) + [self _updateConnectionVariables]; + if (state != SPMySQLConnected) return NO; + + // Update the maximum query size + [self _updateMaxQuerySize]; + + return YES; +} + +/** + * Reconnect to the currently "active" - but possibly disconnected - connection, using the + * stored details. + * Error checks extensively - if this method fails, it will ask how to proceed and loop depending + * on the status, not returning control until either a connection has been established or + * the connection and document have been closed. + * Runs its own autorelease pool as sometimes called in a thread following proxy changes + * (where the return code doesn't matter). + */ +- (BOOL)reconnect +{ + if (userTriggeredDisconnect) return NO; + + NSAutoreleasePool *reconnectionPool = [[NSAutoreleasePool alloc] init]; + + // Check whether a reconnection attempt is already being made - if so, wait + // and return the status of that reconnection attempt. This improves threaded + // use of the connection by preventing reconnect races. + if (isReconnecting) { + + // Loop in a panel runloop mode until the reconnection has processed; if an iteration + // takes less than the requested 0.1s, sleep instead. + while (isReconnecting) { + uint64_t loopIterationStart_t = mach_absolute_time(); + + [[NSRunLoop currentRunLoop] runMode:NSModalPanelRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.1]]; + if (_elapsedSecondsSinceAbsoluteTime(loopIterationStart_t) < 0.1) { + usleep(100000 - (useconds_t)(1000000 * _elapsedSecondsSinceAbsoluteTime(loopIterationStart_t))); + } + } + + [reconnectionPool drain]; + return (state == SPMySQLConnected); + } + + isReconnecting = YES; + + // Store certain details about the connection, so that if the reconnection is successful + // they can be restored. This has to be treated separately from _restoreConnectionDetails + // as a full connection reinitialises certain values from the server. + NSString *preReconnectEncoding = [NSString stringWithString:encoding]; + BOOL preReconnectEncodingUsesLatin1 = encodingUsesLatin1Transport; + NSString *preReconnectDatabase = nil; + if (database) preReconnectDatabase = [NSString stringWithString:database]; + + // If there is a connection proxy, temporarily disassociate the state change action + if (proxy) proxyStateChangeNotificationsIgnored = YES; + + // Close the connection if it's active + [self disconnect]; + + // Lock the connection while waiting for network and proxy + [self _lockConnection]; + + // If no network is present, wait for a short time for one to become available + [self _waitForNetworkConnectionWithTimeout:10]; + + // If there is a proxy, attempt to reconnect it in blocking fashion + if (proxy) { + uint64_t loopIterationStart_t, proxyWaitStart_t; + + // If the proxy is not yet idle after requesting a disconnect, wait for a short time + // to allow it to disconnect. + if ([proxy state] != SPMySQLProxyIdle) { + + proxyWaitStart_t = mach_absolute_time(); + while ([proxy state] != SPMySQLProxyIdle) { + loopIterationStart_t = mach_absolute_time(); + + // If the connection timeout has passed, break out of the loop + if (_elapsedSecondsSinceAbsoluteTime(proxyWaitStart_t) > timeout) break; + + // Allow events to process for 0.25s, sleeping to completion on early return + [[NSRunLoop currentRunLoop] runMode:NSModalPanelRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.25]]; + if (_elapsedSecondsSinceAbsoluteTime(loopIterationStart_t) < 0.25) { + usleep(250000 - (useconds_t)(1000000 * _elapsedSecondsSinceAbsoluteTime(loopIterationStart_t))); + } + } + } + + // Request that the proxy re-establishes its connection + [proxy connect]; + + // Wait while the proxy connects + proxyWaitStart_t = mach_absolute_time(); + while (1) { + loopIterationStart_t = mach_absolute_time(); + + // If the proxy has connected, record the new local port and break out of the loop + if ([proxy state] == SPMySQLProxyConnected) { + port = [proxy localPort]; + break; + } + + // If the proxy connection attempt time has exceeded the timeout, break of of the loop. + if (_elapsedSecondsSinceAbsoluteTime(proxyWaitStart_t) > (timeout + 1)) { + [proxy disconnect]; + break; + } + + // Process events for a short time, allowing dialogs to be shown but waiting for + // the proxy. Capture how long this interface action took, standardising the + // overall time. + [[NSRunLoop mainRunLoop] runMode:NSModalPanelRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0.25]]; + if (_elapsedSecondsSinceAbsoluteTime(loopIterationStart_t) < 0.25) { + usleep((useconds_t)(250000 - (1000000 * _elapsedSecondsSinceAbsoluteTime(loopIterationStart_t)))); + } + + // Extend the connection timeout by any interface time + if ([proxy state] == SPMySQLProxyWaitingForAuth) { + proxyWaitStart_t += mach_absolute_time() - loopIterationStart_t; + } + } + + // Having in theory performed the proxy connect, update state + previousProxyState = [proxy state]; + proxyStateChangeNotificationsIgnored = NO; + } + + // Unlock the connection + [self _unlockConnection]; + + // If not using a proxy, or if the proxy successfully connected, trigger a connection + if (!proxy || [proxy state] == SPMySQLProxyConnected) { + [self connect]; + } + + // If the connection failed, retry the reconnection or cancel as appropriate. + if (state != SPMySQLConnected) { + + // Default to attempting another reconnect + SPMySQLConnectionLostDecision connectionLostDecision = SPMySQLConnectionLostReconnect; + + // If the delegate supports the decision process, ask it how to proceed + if (delegateSupportsConnectionLost) { + connectionLostDecision = [self _delegateDecisionForLostConnection]; + + // Otherwise default to reconnect, but only a set number of times to prevent a runaway loop + } else { + if (reconnectionRetryAttempts < 5) { + connectionLostDecision = SPMySQLConnectionLostReconnect; + } else { + connectionLostDecision = SPMySQLConnectionLostDisconnect; + } + reconnectionRetryAttempts++; + } + + switch (connectionLostDecision) { + case SPMySQLConnectionLostDisconnect: + [self _updateLastErrorMessage:NSLocalizedString(@"User triggered disconnection", @"User triggered disconnection")]; + userTriggeredDisconnect = YES; + isReconnecting = NO; + [reconnectionPool release]; + return NO; + default: + isReconnecting = NO; + [reconnectionPool release]; + return [self reconnect]; + } + } + + // If the connection was successfully established, restore the connection + // state if appropriate. + if (preReconnectDatabase) { + [self selectDatabase:preReconnectDatabase]; + } + [self setEncoding:preReconnectEncoding]; + [self setEncodingUsesLatin1Transport:preReconnectEncodingUsesLatin1]; + + isReconnecting = NO; + [reconnectionPool release]; + return YES; +} + +/** + * Trigger a disconnection if the connection is currently active. + */ +- (void)disconnect +{ + + // Only continue if a connection is active + if (state != SPMySQLConnected && state != SPMySQLConnecting) return; + state = SPMySQLDisconnecting; + + // If a query is active, cancel it + [self cancelCurrentQuery]; + + // Allow any pings or cancelled queries to complete, inside a time limit of ten seconds + uint64_t disconnectStartTime_t = mach_absolute_time(); + do { + usleep(100000); + if (_elapsedSecondsSinceAbsoluteTime(disconnectStartTime_t) > 10) break; + } while (![self _tryLockConnection]); + [self _unlockConnection]; + if (keepAlivePingThread != NULL) pthread_cancel(keepAlivePingThread), keepAlivePingThread = NULL; + + // Close the underlying MySQL connection if it still appears to be active, and not reading + // or writing. While this may result in a leak of the MySQL object, it prevents crashes + // due to attempts to close a blocked/stuck connection. + if (!mySQLConnection->net.reading_or_writing && mySQLConnection->net.vio && mySQLConnection->net.buff) { + mysql_close(mySQLConnection); + } + mySQLConnection = NULL; + + // If using a connection proxy, disconnect that too + if (proxy) { + [proxy performSelectorOnMainThread:@selector(disconnect) withObject:nil waitUntilDone:YES]; + } + + // Clear host-specific information + if (serverVersionString) [serverVersionString release], serverVersionString = nil; + if (database) [database release], database = nil; + + state = SPMySQLDisconnected; +} + +#pragma mark - +#pragma mark Connection state + +/** + * Retrieve whether the connection instance is connected to the remote host. + * Returns NO if the connection is still in process, YES if a disconnection is + * being actively performed. + */ +- (BOOL)isConnected +{ + return (state == SPMySQLConnected || state == SPMySQLDisconnecting); +} + +/** + * Returns YES if the MCPConnection is connected to a server via SSL, NO otherwise. + */ +- (BOOL)isConnectedViaSSL +{ + if (![self isConnected]) return NO; + return connectedWithSSL; +} + +/** + * Checks whether the connection to the server is still active. This verifies + * the connection using a ping, and if the connection is found to be down attempts + * to quickly restore it, including the previous state. + */ +- (BOOL)checkConnection +{ + + // If the connection is not seen as active, don't proceed + if (state != SPMySQLConnected) return NO; + + // Similarly, if the connection is currently locked, that indicates it's in use. This + // could be because queries are actively being run, or that a ping is running. + if ([connectionLock condition] == SPMySQLConnectionBusy) { + + // If a ping thread is not active queries are being performed - return success. + if (!keepAlivePingThreadActive) return YES; + + // If a ping thread is active, wait for it to complete before checking the connection + while (keepAlivePingThreadActive) { + usleep(10000); + } + } + + // Confirm whether the connection is still responding by using a ping + BOOL connectionVerified = [self _pingConnectionUsingLoopDelay:400]; + + // If the connection didn't respond, trigger a reconnect. This will automatically + // attempt to reconnect once, and if that fails will ask the user how to proceed - whether + // to keep reconnecting, or whether to disconnect. + if (!connectionVerified) { + connectionVerified = [self reconnect]; + } + + return connectionVerified; +} + +/** + * Retrieve the time elapsed since the connection was established, in seconds. + * This time is retrieved in a monotonically increasing fashion and is high + * precision; it is used internally for query timing, and is reset on reconnections. + * If no connection is currently active, returns -1. + */ +- (double)timeConnected +{ + if (initialConnectTime == 0) return -1; + + return _elapsedSecondsSinceAbsoluteTime(initialConnectTime); +} + +/** + * Returns YES if the user chose to disconnect at the last "connection failure" + * prompt, NO otherwise. This can be used to alter behaviour in response to state + * changes. + */ +- (BOOL)userTriggeredDisconnect +{ + return userTriggeredDisconnect; +} + +#pragma mark - +#pragma mark General connection utilities + ++ (NSString *)findSocketPath +{ + NSFileManager *fileManager = [NSFileManager defaultManager]; + + NSArray *possibleSocketLocations = [NSArray arrayWithObjects: + @"/tmp/mysql.sock", // Default + @"/Applications/MAMP/tmp/mysql/mysql.sock", // MAMP default location + @"/Applications/xampp/xamppfiles/var/mysql/mysql.sock", // XAMPP default location + @"/var/mysql/mysql.sock", // Mac OS X Server default + @"/opt/local/var/run/mysqld/mysqld.sock", // Darwinports MySQL + @"/opt/local/var/run/mysql4/mysqld.sock", // Darwinports MySQL 4 + @"/opt/local/var/run/mysql5/mysqld.sock", // Darwinports MySQL 5 + @"/usr/local/zend/mysql/tmp/mysql.sock", // Zend Server CE (see Issue #1251) + @"/var/run/mysqld/mysqld.sock", // As used on Debian/Gentoo + @"/var/tmp/mysql.sock", // As used on FreeBSD + @"/var/lib/mysql/mysql.sock", // As used by Fedora + @"/opt/local/lib/mysql/mysql.sock", // Alternate fedora + nil]; + + for (NSUInteger i = 0; i < [possibleSocketLocations count]; i++) { + if ([fileManager fileExistsAtPath:[possibleSocketLocations objectAtIndex:i]]) + return [possibleSocketLocations objectAtIndex:i]; + } + + return nil; +} + +@end + +#pragma mark - +#pragma mark Private API + +@implementation SPMySQLConnection (PrivateAPI) + +/** + * Make a connection using the class connection settings, returning a MySQL + * connection object on success. + */ +- (MYSQL *)_makeRawMySQLConnectionWithEncoding:(NSString *)encodingName isMasterConnection:(BOOL)isMaster +{ + + // Set up the MySQL connection object + MYSQL *theConnection = mysql_init(NULL); + if (!theConnection) return NULL; + + // Disable automatic reconnection, as it's handled in-framework to preserve + // options, encodings and connection state. + my_bool falseMyBool = FALSE; + mysql_options(theConnection, MYSQL_OPT_RECONNECT, &falseMyBool); + + // Set the connection timeout + mysql_options(theConnection, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&timeout); + + // Set the connection encoding + mysql_options(theConnection, MYSQL_SET_CHARSET_NAME, [encodingName UTF8String]); + + // Set up the connection variables in the format MySQL needs, from the class-wide variables + const char *theHost = NULL; + const char *theUsername = ""; + const char *thePassword = NULL; + const char *theSocket = NULL; + + if (host) theHost = [self _cStringForString:host]; + if (username) theUsername = [self _cStringForString:username]; + + // If a password was supplied, use it; otherwise ask the delegate if appropriate + if (password) { + thePassword = [self _cStringForString:password]; + } else if ([delegate respondsToSelector:@selector(keychainPasswordForConnection:)]) { + thePassword = [self _cStringForString:[delegate keychainPasswordForConnection:self]]; + } + + // If set to use a socket and a socket was supplied, use it; otherwise, search for a socket to use + if (useSocket) { + if (socketPath) { + theSocket = [self _cStringForString:socketPath]; + } else { + theSocket = [self _cStringForString:[SPMySQLConnection findSocketPath]]; + } + } + + // Apply SSL if appropriate + if (useSSL) { + const char *theSSLKeyFilePath = NULL; + const char *theSSLCertificatePath = NULL; + const char *theCACertificatePath = NULL; + + if (sslKeyFilePath) { + theSSLKeyFilePath = [[sslKeyFilePath stringByExpandingTildeInPath] UTF8String]; + } + if (sslCertificatePath) { + theSSLCertificatePath = [[sslCertificatePath stringByExpandingTildeInPath] UTF8String]; + } + if (sslCACertificatePath) { + theCACertificatePath = [[sslCACertificatePath stringByExpandingTildeInPath] UTF8String]; + } + + mysql_ssl_set(theConnection, theSSLKeyFilePath, theSSLCertificatePath, theCACertificatePath, NULL, SPMySQLSSLPermissibleCiphers); + } + + MYSQL *connectionStatus = mysql_real_connect(theConnection, theHost, theUsername, thePassword, NULL, (unsigned int)port, theSocket, SPMySQLConnectionOptions); + + // If the connection failed, return NULL + if (theConnection != connectionStatus) { + + // If the connection is the master connection, record the error state + if (isMaster) { + [self _updateLastErrorMessage:[self _stringForCString:mysql_error(theConnection)]]; + [self _updateLastErrorID:mysql_errno(theConnection)]; + } + + return NULL; + } + + // Ensure automatic reconnection is disabled for older versions + theConnection->reconnect = 0; + + // Successful connection - return the handle + return theConnection; +} + +/** + * Loop while a connection isn't available; allows blocking while the network is disconnected + * or still connecting (eg Airport still coming up after sleep). + */ +- (BOOL)_waitForNetworkConnectionWithTimeout:(double)timeoutSeconds +{ + BOOL hostReachable; + Boolean flagsValid; + SCNetworkReachabilityRef reachabilityTarget; + SCNetworkConnectionFlags reachabilityStatus; + + // Set up the reachability target - the host is not important, and is not connected to. + reachabilityTarget = SCNetworkReachabilityCreateWithName(NULL, "dev.mysql.com"); + + // In a loop until success or the timeout, test reachability + uint64_t loopStart_t = mach_absolute_time(); + while (1) { + + // Check reachability + flagsValid = SCNetworkReachabilityGetFlags(reachabilityTarget, &reachabilityStatus); + + hostReachable = flagsValid ? YES : NO; + + // Ensure that the network is reachable + if (hostReachable && !(reachabilityStatus & kSCNetworkFlagsReachable)) hostReachable = NO; + + // Ensure that Airport is up/connected if present + if (hostReachable && (reachabilityStatus & kSCNetworkFlagsConnectionRequired)) hostReachable = NO; + + // If the host *is* reachable, return success + if (hostReachable) return YES; + + // If the timeout has been exceeded, break out of the loop + if (_elapsedSecondsSinceAbsoluteTime(loopStart_t) >= timeoutSeconds) break; + + // Sleep before the next loop iteration + usleep(250000); + } + + // All checks failed - return failure + return NO; +} + +/** + * Update connection variables from the server, collecting state and ensuring + * settings like encoding are in sync. + */ +- (void)_updateConnectionVariables +{ + if (state != SPMySQLConnected && state != SPMySQLConnecting) return; + + // Retrieve all variables from the server in a single query + SPMySQLResult *theResult = [self queryString:@"SHOW VARIABLES"]; + if (![theResult numberOfRows]) return; + + // SHOW VARIABLES can return binary results on certain MySQL 4 versions; ensure string output + [theResult setReturnDataAsStrings:YES]; + + // Convert the result set into a variables dictionary + [theResult setDefaultRowReturnType:SPMySQLResultRowAsArray]; + NSMutableDictionary *variables = [NSMutableDictionary new]; + for (NSArray *variableRow in theResult) { + [variables setObject:[variableRow objectAtIndex:1] forKey:[variableRow objectAtIndex:0]]; + } + + // Copy the server version string to the instance variable + if (serverVersionString) [serverVersionString release], serverVersionString = nil; + serverVersionString = [[variables objectForKey:@"version"] retain]; + + // Get the connection encoding. Although a specific encoding may have been requested on + // connection, it may be overridden by init_connect commands or connection state changes. + // Default to latin1 for older server versions. + NSString *retrievedEncoding = @"latin1"; + if ([variables objectForKey:@"character_set_results"]) { + retrievedEncoding = [variables objectForKey:@"character_set_results"]; + } else if ([variables objectForKey:@"character_set"]) { + retrievedEncoding = [variables objectForKey:@"character_set"]; + } + + // Update instance variables + if (encoding) [encoding release]; + encoding = [[NSString alloc] initWithString:retrievedEncoding]; + stringEncoding = [SPMySQLConnection stringEncodingForMySQLCharset:[self _cStringForString:encoding]]; + encodingUsesLatin1Transport = NO; + + // Check the interactive timeout - if it's below five minutes, increase it to ten + // to imprive timeout/keepalive behaviour + if ([variables objectForKey:@"interactive_timeout"]) { + if ([[variables objectForKey:@"interactive_timeout"] integerValue] < 300) { + [self queryString:@"SET interactive_timeout=600"]; + } + } + + [variables release]; +} + +/** + * Restore the connection encoding details as necessary based on previously set + * details. + */ +- (void)_restoreConnectionVariables +{ + mysqlConnectionThreadId = mySQLConnection->thread_id; + initialConnectTime = mach_absolute_time(); + + [self selectDatabase:database]; + + [self setEncoding:encoding]; + [self setEncodingUsesLatin1Transport:encodingUsesLatin1Transport]; +} + +/** + * If thirty seconds have passed since the last time the connection was + * used, check the connection. + * This minimises the impact of continuous additional connection checks - + * each of which requires a round trip to the server - but handles most + * network issues. + * Returns whether the connection is considered still valid. + */ +- (BOOL)_checkConnectionIfNecessary +{ + + // If the connection was recently used, return success + if (_elapsedSecondsSinceAbsoluteTime(lastConnectionUsedTime) < 30) return YES; + + // Otherwise check the connection + return [self checkConnection]; +} +@end |