// // $Id$ // // CMMCPConnection.m // sequel-pro // // Created by lorenz textor (lorenz@textor.ch) on Wed Sept 21 2005. // Copyright (c) 2002-2003 Lorenz Textor. All rights reserved. // // This program is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 2 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA // // More info at #import "CMMCPConnection.h" #include #include static jmp_buf pingTimeoutJumpLocation; static void forcePingTimeout(int signalNumber); @interface CMMCPConnection(hidden) - (void)getServerVersionString; @end @implementation CMMCPConnection(hidden) - (void)getServerVersionString { if( mConnected ) { CMMCPResult *theResult; theResult = [self queryString:@"SHOW VARIABLES WHERE Variable_name = 'version'"]; if ([theResult numOfRows]) { [theResult dataSeek:0]; serverVersionString = [[NSString stringWithString:[[theResult fetchRowAsArray] objectAtIndex:1]] retain]; } } } @end @implementation CMMCPConnection /* * Override the normal init methods, extending them to also init additional details, * and to store details of the initialised connection to allow reconnection as method. * Note this also behaves differently from the standard MCPKit connection methods - * passwords are passed separately, and connections are not automatically made on init. */ - (id) init { [self initSPExtensions]; self = [super init]; serverVersionString = nil; return self; } - (id) initToHost:(NSString *) host withLogin:(NSString *) login usingPort:(int) port { [self initSPExtensions]; self = [super init]; mEncoding = NSISOLatin1StringEncoding; mConnection = mysql_init(mConnection); mConnected = NO; if (mConnection == NULL) { [self autorelease]; return nil; } mConnectionFlags = kMCPConnectionDefaultOption; connectionHost = [[NSString alloc] initWithString:host]; connectionLogin = [[NSString alloc] initWithString:login]; connectionPort = port; connectionSocket = nil; return self; } - (id) initToSocket:(NSString *) socket withLogin:(NSString *) login { [self initSPExtensions]; self = [super init]; mEncoding = NSISOLatin1StringEncoding; mConnection = mysql_init(mConnection); mConnected = NO; if (mConnection == NULL) { [self autorelease]; return nil; } mConnectionFlags = kMCPConnectionDefaultOption; connectionHost = nil; connectionLogin = [[NSString alloc] initWithString:login]; connectionSocket = [[NSString alloc] initWithString:socket]; connectionPort = 0; return self; } /* * Instantiate extra variables and load the connection error dialog for potential use. */ - (void) initSPExtensions { parentWindow = nil; connectionPassword = nil; connectionKeychainName = nil; connectionKeychainAccount = nil; keepAliveTimer = nil; connectionTunnel = nil; connectionTimeout = [[[NSUserDefaults standardUserDefaults] objectForKey:@"ConnectionTimeout"] intValue]; if (!connectionTimeout) connectionTimeout = 10; useKeepAlive = [[[NSUserDefaults standardUserDefaults] objectForKey:@"UseKeepAlive"] doubleValue]; keepAliveInterval = [[[NSUserDefaults standardUserDefaults] objectForKey:@"KeepAliveInterval"] doubleValue]; if (!keepAliveInterval) keepAliveInterval = 0; lastKeepAliveSuccess = nil; lastQueryExecutionTime = 0; if (![NSBundle loadNibNamed:@"ConnectionErrorDialog" owner:self]) { NSLog(@"Connection error dialog could not be loaded; connection failure handling will not function correctly."); } } /* * Sets the password to be stored locally. * Providing a keychain name is much more secure. */ - (BOOL) setPassword:(NSString *)thePassword { if (connectionPassword) [connectionPassword release], connectionPassword = nil; if (connectionKeychainName) [connectionKeychainName release], connectionKeychainName = nil; if (connectionKeychainAccount) [connectionKeychainAccount release], connectionKeychainAccount = nil; connectionPassword = [[NSString alloc] initWithString:thePassword]; return YES; } /* * Sets the keychain name to use to retrieve the password. This is the recommended and * secure way of supplying a password to the SSH tunnel. */ - (BOOL) setPasswordKeychainName:(NSString *)theName account:(NSString *)theAccount { if (connectionPassword) [connectionPassword release], connectionPassword = nil; if (connectionKeychainName) [connectionKeychainName release], connectionKeychainName = nil; if (connectionKeychainAccount) [connectionKeychainAccount release], connectionKeychainAccount = nil; connectionKeychainName = [[NSString alloc] initWithString:theName]; connectionKeychainAccount = [[NSString alloc] initWithString:theAccount]; return YES; } /* * Set a SSH tunnel object to connect through. This object will be retained locally, * and will be automatically connected/connection checked/reconnected/disconnected * together with the main connection. */ - (BOOL) setSSHTunnel:(SPSSHTunnel *)theTunnel { connectionTunnel = theTunnel; [connectionTunnel retain]; currentSSHTunnelState = [connectionTunnel state]; [connectionTunnel setConnectionStateChangeSelector:@selector(sshTunnelStateChange:) delegate:self]; return YES; } /* * Add a new connection method, intended for use with the init methods above. * Uses the stored details to instantiate a connection to the specified server, * including custom timeouts - used for pings, not for long-running commands. */ - (BOOL) connect { const char *theLogin = [self cStringFromString:connectionLogin]; const char *theHost; const char *thePass; const char *theSocket; void *theRet; // Ensure that a password method has been provided if (connectionKeychainName == nil && connectionPassword == nil) return NO; // Start the keepalive timer [self startKeepAliveTimerResettingState:YES]; // Disconnect if a connection is already active if (mConnected) { [self disconnect]; mConnection = mysql_init(NULL); if (mConnection == NULL) return NO; } // Ensure the custom timeout option is set if (mConnection != NULL) { mysql_options(mConnection, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&connectionTimeout); } // Set the host as appropriate if (!connectionHost || ![connectionHost length]) { theHost = NULL; } else { theHost = [self cStringFromString:connectionHost]; } // Use the default socket if none is set, or set appropriately if (connectionSocket == nil || ![connectionSocket length]) { theSocket = kMCPConnectionDefaultSocket; } else { theSocket = [self cStringFromString:connectionSocket]; } // Select the password from the provided method if (connectionKeychainName) { KeyChain *keychain; keychain = [[KeyChain alloc] init]; thePass = [self cStringFromString:[keychain getPasswordForName:connectionKeychainName account:connectionKeychainAccount]]; [keychain release]; } else { thePass = [self cStringFromString:connectionPassword]; } // Connect theRet = mysql_real_connect(mConnection, theHost, theLogin, thePass, NULL, connectionPort, theSocket, mConnectionFlags); thePass = NULL; if (theRet != mConnection) { return mConnected = NO; } mConnected = YES; mEncoding = [MCPConnection encodingForMySQLEncoding:mysql_character_set_name(mConnection)]; [self timeZone]; // Getting the timezone used by the server. return mConnected; } /* * Override the stored disconnection method to ensure that disconnecting clears stored timers. */ - (void) disconnect { [super disconnect]; if (connectionTunnel) [connectionTunnel disconnect]; if( serverVersionString != nil ) { [serverVersionString release]; serverVersionString = nil; } [self stopKeepAliveTimer]; } /* * return the server major version or -1 on fail */ - (int)serverMajorVersion { if( mConnected ) { if( serverVersionString == nil ) { [self getServerVersionString]; } if( serverVersionString != nil ) { return [[[serverVersionString componentsSeparatedByString:@"."] objectAtIndex:0] intValue]; } } return -1; } /* * return the server minor version or -1 on fail */ - (int)serverMinorVersion { if( mConnected ) { if( serverVersionString == nil ) { [self getServerVersionString]; } if( serverVersionString != nil ) { return [[[serverVersionString componentsSeparatedByString:@"."] objectAtIndex:1] intValue]; } } return -1; } /* * return the server release version or -1 on fail */ - (int)serverReleaseVersion { if( mConnected ) { if( serverVersionString == nil ) { [self getServerVersionString]; } if( serverVersionString != nil ) { NSString *s = [[serverVersionString componentsSeparatedByString:@"."] objectAtIndex:2]; return [[[s componentsSeparatedByString:@"-"] objectAtIndex:0] intValue]; } } return -1; } /* * 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. */ - (BOOL) reconnect { NSString *currentEncoding = nil; BOOL currentEncodingUsesLatin1Transport = NO; NSString *currentDatabase = nil; // Store the current database and encoding so they can be re-set if reconnection was successful if (delegate && [delegate valueForKey:@"selectedDatabase"]) { currentDatabase = [NSString stringWithString:[delegate valueForKey:@"selectedDatabase"]]; } if (delegate && [delegate valueForKey:@"_encoding"]) { currentEncoding = [NSString stringWithString:[delegate valueForKey:@"_encoding"]]; } if (delegate && [delegate respondsToSelector:@selector(connectionEncodingViaLatin1)]) { currentEncodingUsesLatin1Transport = [delegate connectionEncodingViaLatin1]; } // Close the connection if it exists. if (mConnected) { mysql_close(mConnection); mConnection = NULL; } mConnected = NO; // If there is a tunnel, ensure it's disconnected and attempt to reconnect it in blocking fashion if (connectionTunnel) { [connectionTunnel setConnectionStateChangeSelector:nil delegate:nil]; if ([connectionTunnel state] != SPSSH_STATE_IDLE) [connectionTunnel disconnect]; [connectionTunnel connect]; NSDate *tunnelStartDate = [NSDate date]; // Allow the tunnel to attempt to connect in a loop while (1) { if ([connectionTunnel state] == SPSSH_STATE_CONNECTED) { connectionPort = [connectionTunnel localPort]; break; } if ([[NSDate date] timeIntervalSinceDate:tunnelStartDate] > (connectionTimeout + 1)) { [connectionTunnel disconnect]; break; } [NSThread sleepForTimeInterval:0.25]; } currentSSHTunnelState = [connectionTunnel state]; [connectionTunnel setConnectionStateChangeSelector:@selector(sshTunnelStateChange:) delegate:self]; } if (!connectionTunnel || [connectionTunnel state] == SPSSH_STATE_CONNECTED) { // Attempt to reinitialise the connection - if this fails, it will still be set to NULL. if (mConnection == NULL) { mConnection = mysql_init(NULL); } if (mConnection != NULL) { // Set a connection timeout for the new connection mysql_options(mConnection, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&connectionTimeout); // Attempt to reestablish the connection [self connect]; } } // If the connection was successfully established, reselect the old database and encoding if appropriate. if (mConnected) { if (currentDatabase) { [self selectDB:currentDatabase]; } if (currentEncoding) { [self queryString:[NSString stringWithFormat:@"/*!40101 SET NAMES '%@' */", currentEncoding]]; [self setEncoding:[CMMCPConnection encodingForMySQLEncoding:[currentEncoding UTF8String]]]; if (currentEncodingUsesLatin1Transport) { [self queryString:@"/*!40101 SET CHARACTER_SET_RESULTS=latin1 */"]; } } } else if (parentWindow) { // If the connection was not successfully established, ask how to proceed. [NSApp beginSheet:connectionErrorDialog modalForWindow:parentWindow modalDelegate:self didEndSelector:nil contextInfo:nil]; int connectionErrorCode = [NSApp runModalForWindow:connectionErrorDialog]; [NSApp endSheet:connectionErrorDialog]; [connectionErrorDialog orderOut:nil]; switch (connectionErrorCode) { // Should disconnect case 2: [parentWindow close]; return NO; // Should retry default: return [self reconnect]; } } return mConnected; } /* * Set the parent window of the connection for use with dialogs. */ - (void)setParentWindow:(NSWindow *)theWindow { parentWindow = theWindow; } /* * Handle any state changes in the associated SSH Tunnel */ - (void)sshTunnelStateChange:(SPSSHTunnel *)theTunnel { int newState = [theTunnel state]; // Restart the tunnel if it dies if (mConnected && newState == SPSSH_STATE_IDLE && currentSSHTunnelState == SPSSH_STATE_CONNECTED) { currentSSHTunnelState = newState; [connectionTunnel setConnectionStateChangeSelector:nil delegate:nil]; [self reconnect]; return; } currentSSHTunnelState = newState; } /* * Ends and existing modal session */ - (IBAction) closeSheet:(id)sender { [NSApp stopModalWithCode:[sender tag]]; } /* * Gets a proper NSStringEncoding according to the given MySQL charset. * * MySQL 4.0 offers this charsets: * big5 cp1251 cp1257 croat czech danish dec8 dos estonia euc_kr gb2312 gbk german1 * greek hebrew hp8 hungarian koi8_ru koi8_ukr latin1 latin1_de latin2 latin5 sjis * swe7 tis620 ujis usa7 win1250 win1251ukr * * WARNING : incomplete implementation. Please, send your fixes. */ + (NSStringEncoding) encodingForMySQLEncoding:(const char *) mysqlEncoding { // Unicode encodings: if (!strncmp(mysqlEncoding, "utf8", 4)) { return NSUTF8StringEncoding; } if (!strncmp(mysqlEncoding, "ucs2", 4)) { return NSUnicodeStringEncoding; } // Roman alphabet encodings: if (!strncmp(mysqlEncoding, "ascii", 5)) { return NSASCIIStringEncoding; } if (!strncmp(mysqlEncoding, "latin1", 6)) { return NSISOLatin1StringEncoding; } if (!strncmp(mysqlEncoding, "macroman", 8)) { return NSMacOSRomanStringEncoding; } // Roman alphabet with central/east european additions: if (!strncmp(mysqlEncoding, "latin2", 6)) { return NSISOLatin2StringEncoding; } if (!strncmp(mysqlEncoding, "cp1250", 6)) { return NSWindowsCP1250StringEncoding; } if (!strncmp(mysqlEncoding, "win1250", 7)) { return NSWindowsCP1250StringEncoding; } if (!strncmp(mysqlEncoding, "cp1257", 6)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingWindowsBalticRim); } // Additions for Turkish: if (!strncmp(mysqlEncoding, "latin5", 6)) { return NSWindowsCP1254StringEncoding; } // Greek: if (!strncmp(mysqlEncoding, "greek", 5)) { return NSWindowsCP1253StringEncoding; } // Cyrillic: if (!strncmp(mysqlEncoding, "win1251ukr", 6)) { return NSWindowsCP1251StringEncoding; } if (!strncmp(mysqlEncoding, "cp1251", 6)) { return NSWindowsCP1251StringEncoding; } if (!strncmp(mysqlEncoding, "koi8_ru", 6)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingKOI8_R); } if (!strncmp(mysqlEncoding, "koi8_ukr", 6)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingKOI8_R); } // Arabic: if (!strncmp(mysqlEncoding, "cp1256", 6)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingWindowsArabic); } // Hebrew: if (!strncmp(mysqlEncoding, "hebrew", 6)) { CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingISOLatinHebrew); } // Asian: if (!strncmp(mysqlEncoding, "ujis", 4)) { return NSJapaneseEUCStringEncoding; } if (!strncmp(mysqlEncoding, "sjis", 4)) { return NSShiftJISStringEncoding; } if (!strncmp(mysqlEncoding, "big5", 4)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingBig5); } if (!strncmp(mysqlEncoding, "euc_kr", 6)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingEUC_KR); } if (!strncmp(mysqlEncoding, "euckr", 5)) { return CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingEUC_KR); } // Default to iso latin 1, even if it is not exact (throw an exception?) NSLog(@"WARNING : unknown name for MySQL encoding '%s'!\n\t\tFalling back to iso-latin1.", mysqlEncoding); return NSISOLatin1StringEncoding; } /* * Modified version of selectDB to be used in Sequel Pro. * Checks the connection exists, and handles keepalive, otherwise calling the parent implementation. */ - (BOOL) selectDB:(NSString *) dbName { if (!mConnected) return NO; [self stopKeepAliveTimer]; if (![self checkConnection]) return NO; if ([super selectDB:dbName]) { [self startKeepAliveTimerResettingState:YES]; return YES; } return NO; } /* * Override the standard queryString: method to default to the connection encoding, as before, * before pssing on to queryString: usingEncoding:. */ - (CMMCPResult *)queryString:(NSString *) query { return [self queryString:query usingEncoding:mEncoding]; } /* * Modified version of queryString to be used in Sequel Pro. * Error checks extensively - if this method fails, it will ask how to proceed and loop depending * on the status, not returning control until either the query has been executed and the result can * be returned or the connection and document have been closed. */ - (CMMCPResult *)queryString:(NSString *) query usingEncoding:(NSStringEncoding) encoding { CMMCPResult *theResult; const char *theCQuery; int theQueryCode; NSDate *queryStartDate; // If no connection is present, return nil. if (!mConnected) return nil; [self stopKeepAliveTimer]; // Generate the cString as appropriate theCQuery = [self cStringFromString:query usingEncoding:encoding]; // Check the connection. This triggers reconnects as necessary, and should only return false if a disconnection // has been requested - in which case return nil if (![self checkConnection]) return nil; // Inform the delegate about the query if (delegate && [delegate respondsToSelector:@selector(willQueryString:)]) { [delegate willQueryString:query]; } // Run the query, storing run time (note this will include some network and overhead) queryStartDate = [NSDate date]; theQueryCode = mysql_query(mConnection, theCQuery); lastQueryExecutionTime = [[NSDate date] timeIntervalSinceDate:queryStartDate]; // Retrieve the result or error appropriately. if (0 == theQueryCode) { if (mysql_field_count(mConnection) != 0) { // Use CMMCPResult instead of MCPResult theResult = [[CMMCPResult alloc] initWithMySQLPtr:mConnection encoding:mEncoding timeZone:mTimeZone]; } else { return nil; } } else { // Inform the delegate about errors if (delegate && [delegate respondsToSelector:@selector(queryGaveError:)]) { [delegate queryGaveError:[self getLastErrorMessage]]; } return nil; } [self startKeepAliveTimerResettingState:YES]; return [theResult autorelease]; } /* * Return the time taken to execute the last query. This should be close to the time it took * the server to run the query, but will include network lag and some client library overhead. */ - (float) lastQueryExecutionTime { return lastQueryExecutionTime; } /* * Modified version of selectDB to be used in Sequel Pro. * Checks the connection exists, and handles keepalive, otherwise calling the parent implementation. */ - (MCPResult *) listDBsLike:(NSString *) dbsName { if (!mConnected) return NO; [self stopKeepAliveTimer]; if (![self checkConnection]) return [[[MCPResult alloc] init] autorelease]; [self startKeepAliveTimerResettingState:YES]; return [super listDBsLike:dbsName]; } /* * Checks whether the connection to the server is still active. If not, prompts for what approach to take, * offering to retry, reconnect or disconnect the connection. */ - (BOOL)checkConnection { unsigned long threadid; if (!mConnected) return NO; BOOL connectionVerified = FALSE; // Get the current thread ID for this connection threadid = mConnection->thread_id; // Check whether the connection is still operational via a wrapped version of MySQL ping. connectionVerified = [self pingConnection]; // If the connection doesn't appear to be responding, show a dialog asking how to proceed if (!connectionVerified) { [NSApp beginSheet:connectionErrorDialog modalForWindow:parentWindow modalDelegate:self didEndSelector:nil contextInfo:nil]; int responseCode = [NSApp runModalForWindow:connectionErrorDialog]; [NSApp endSheet:connectionErrorDialog]; [connectionErrorDialog orderOut:nil]; switch (responseCode) { // "Reconnect" has been selected. Request a reconnect, and retry. case 1: [self reconnect]; return [self checkConnection]; // "Disconnect" has been selected. Close the parent window, which will handle disconnections, and return false. case 2: [parentWindow close]; return FALSE; // "Retry" has been selected - return a recursive call. default: return [self checkConnection]; } // If a connection exists, check whether the thread id differs; if so, the connection has // probably been reestablished and we need to reset the connection encoding } else if (threadid != mConnection->thread_id) { if (delegate && [delegate valueForKey:@"_encoding"]) { [self queryString:[NSString stringWithFormat:@"/*!40101 SET NAMES '%@' */", [NSString stringWithString:[delegate valueForKey:@"_encoding"]]]]; if (delegate && [delegate respondsToSelector:@selector(connectionEncodingViaLatin1)]) { if ([delegate connectionEncodingViaLatin1]) [self queryString:@"/*!40101 SET CHARACTER_SET_RESULTS=latin1 */"]; } } } return connectionVerified; } - (void)setDelegate:(id)object { delegate = object; } /* Getting the currently used time zone (in communication with the DB server). */ /* fixes mysql 4.1.14 problem, can be deleted as soon as fixed in the framework */ - (NSTimeZone *)timeZone { if ([self checkConnection]) { MCPResult *theSessionTZ = [self queryString:@"SHOW VARIABLES LIKE '%time_zone'"]; NSArray *theRow; id theTZName; NSTimeZone *theTZ; [theSessionTZ dataSeek:1ULL]; theRow = [theSessionTZ fetchRowAsArray]; theTZName = [theRow objectAtIndex:1]; if ( [theTZName isKindOfClass:[NSData class]] ) { // MySQL 4.1.14 returns the mysql variables as NSData theTZName = [self stringWithText:theTZName]; } if ([theTZName isEqualToString:@"SYSTEM"]) { [theSessionTZ dataSeek:0ULL]; theRow = [theSessionTZ fetchRowAsArray]; theTZName = [theRow objectAtIndex:1]; if ( [theTZName isKindOfClass:[NSData class]] ) { // MySQL 4.1.14 returns the mysql variables as NSData theTZName = [self stringWithText:theTZName]; } } if (theTZName) { // Old versions of the server does not support there own time zone ? theTZ = [NSTimeZone timeZoneWithName:theTZName]; } else { // By default set the time zone to the local one.. // Try to get the name using the previously available variable: theSessionTZ = [self queryString:@"SHOW VARIABLES LIKE 'timezone'"]; [theSessionTZ dataSeek:0ULL]; theRow = [theSessionTZ fetchRowAsArray]; theTZName = [theRow objectAtIndex:1]; if (theTZName) { // Finally we found one ... theTZ = [NSTimeZone timeZoneWithName:theTZName]; } else { theTZ = [NSTimeZone defaultTimeZone]; //theTZ = [NSTimeZone systemTimeZone]; NSLog(@"The time zone is not defined on the server, set it to the default one : %@", theTZ); } } if (theTZ != mTimeZone) { [mTimeZone release]; mTimeZone = [theTZ retain]; } } return mTimeZone; } /* * The current versions of MCPKit (and up to and including 3.0.1) use MySQL 4.1.12; this has an issue with * mysql_ping where a connection which is terminated will cause mysql_ping never to respond, even when * connection timeouts are set. Full details of this issue are available at http://bugs.mysql.com/bug.php?id=9678 ; * this bug was fixed in 4.1.22 and later versions. * This issue can be replicated by connecting to a remote host, and then configuring a firewall on that host * to drop all packets on the connected port - mysql_ping and so Sequel Pro will hang. * Until the client libraries are updated, this provides a drop-in wrapper for mysql_ping, which calls mysql_ping * while running a SIGALRM to enforce the specified connection time. This is low-level but effective. * Unlike mysql_ping, this function returns FALSE on failure and TRUE on success. */ - (BOOL) pingConnection { struct sigaction timeoutAction; NSDate *startDate = [[NSDate alloc] initWithTimeIntervalSinceNow:0]; BOOL pingSuccess = FALSE; // Construct the SIGALRM to fire after the connection timeout if it isn't cleared, calling the forcePingTimeout function. timeoutAction.sa_handler = forcePingTimeout; sigemptyset(&timeoutAction.sa_mask); timeoutAction.sa_flags = 0; sigaction(SIGALRM, &timeoutAction, NULL); alarm(connectionTimeout+1); // Set up a "restore point", returning 0; if longjmp is used later with this reference, execution // jumps back to this point and returns a nonzero value, so this function evaluates to false when initially // set and true if it's called again. if (setjmp(pingTimeoutJumpLocation)) { // The connection timed out - we want to return false. pingSuccess = FALSE; // On direct execution: } else { // Run mysql_ping, which returns 0 on success, and otherwise an error. pingSuccess = (BOOL)(! mysql_ping(mConnection)); // If the ping failed within a second, try another one; this is because a terminated-but-then // restored connection is at times restored or functional after a ping, but the ping still returns // an error. This additional check ensures the returned status is correct with minimal other effect. if (!pingSuccess && ([startDate timeIntervalSinceNow] > -1)) { pingSuccess = (BOOL)(! mysql_ping(mConnection)); } } // Reset and clear the SIGALRM used to check connection timeouts. alarm(0); timeoutAction.sa_handler = SIG_IGN; sigemptyset(&timeoutAction.sa_mask); timeoutAction.sa_flags = 0; sigaction(SIGALRM, &timeoutAction, NULL); [startDate release]; return pingSuccess; } /* * This function is paired with pingConnection, and provides a method of enforcing the connection * timeout when mysql_ping does not respect the specified limits. */ static void forcePingTimeout(int signalNumber) { longjmp(pingTimeoutJumpLocation, 1); } /* * Restarts a keepalive to fire in the future. */ - (void) startKeepAliveTimerResettingState:(BOOL)resetState { if (keepAliveTimer) [self stopKeepAliveTimer]; if (!mConnected) return; if (resetState && lastKeepAliveSuccess) { [lastKeepAliveSuccess release]; lastKeepAliveSuccess = nil; } if (useKeepAlive && keepAliveInterval) { keepAliveTimer = [NSTimer scheduledTimerWithTimeInterval:keepAliveInterval target:self selector:@selector(keepAlive:) userInfo:nil repeats:NO]; [keepAliveTimer retain]; } } /* * Stops a keepalive if one is set for the future. */ - (void) stopKeepAliveTimer { if (!keepAliveTimer) return; [keepAliveTimer invalidate]; [keepAliveTimer release]; keepAliveTimer = nil; } /* * Keeps a connection alive by running a ping. */ - (void) keepAlive:(NSTimer *)theTimer { if (!mConnected) return; // If there a successful keepalive record exists, and it was more than 5*keepaliveinterval ago, // abort. This prevents endless spawning of threads in a state where the connection has been // cut but mysql doesn't pick up on the fact - see comment for pingConnection above. The same // forced-timeout approach cannot be used here on a background thread. // When the connection is disconnected in code, these 5 "hanging" threads are automatically cleaned. if (lastKeepAliveSuccess && [lastKeepAliveSuccess timeIntervalSinceNow] < -5 * keepAliveInterval) return; [NSThread detachNewThreadSelector:@selector(threadedKeepAlive) toTarget:self withObject:nil]; [self startKeepAliveTimerResettingState:NO]; } /* * A threaded keepalive to avoid blocking the interface */ - (void) threadedKeepAlive { if (!mConnected) return; mysql_ping(mConnection); if (lastKeepAliveSuccess) { [lastKeepAliveSuccess release]; lastKeepAliveSuccess = nil; } lastKeepAliveSuccess = [[NSDate alloc] initWithTimeIntervalSinceNow:0]; } /* * Modified version of the original to support a supplied encoding. * For internal use only. Transforms a NSString to a C type string (ending with \0). * Lossy conversions are enabled. */ - (const char *) cStringFromString:(NSString *) theString usingEncoding:(NSStringEncoding) encoding { NSMutableData *theData; if (! theString) { return (const char *)NULL; } theData = [NSMutableData dataWithData:[theString dataUsingEncoding:encoding allowLossyConversion:YES]]; [theData increaseLengthBy:1]; return (const char *)[theData bytes]; } @end