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-rw-r--r--Source/CMMCPConnection.m330
1 files changed, 312 insertions, 18 deletions
diff --git a/Source/CMMCPConnection.m b/Source/CMMCPConnection.m
index 8d4e2673..20f5ba11 100644
--- a/Source/CMMCPConnection.m
+++ b/Source/CMMCPConnection.m
@@ -23,10 +23,191 @@
// Or mail to <lorenz@textor.ch>
#import "CMMCPConnection.h"
+#include <unistd.h>
+#include <setjmp.h>
+static jmp_buf pingTimeoutJumpLocation;
+static void forcePingTimeout(int signalNumber);
@implementation CMMCPConnection
+
+/*
+ * Override the normal init methods, extending them to also init additional details.
+ */
+- (id) init
+{
+ [self initSPExtensions];
+ self = [super init];
+ return self;
+}
+- (id) initToHost:(NSString *) host withLogin:(NSString *) login password:(NSString *) pass usingPort:(int) port
+{
+ [self initSPExtensions];
+ self = [super initToHost:host withLogin:login password:pass usingPort:port];
+ return self;
+}
+- (id) initToSocket:(NSString *) socket withLogin:(NSString *) login password:(NSString *) pass
+{
+ [self initSPExtensions];
+ self = [super initToSocket:socket withLogin:login password:pass];
+ return self;
+}
+
+
+/*
+ * Instantiate extra variables and load the connection error dialog for potential use.
+ */
+- (void) initSPExtensions
+{
+ parentWindow = nil;
+ connectionLogin = nil;
+ connectionPassword = nil;
+ connectionHost = nil;
+ connectionPort = 0;
+ connectionSocket = nil;
+ [NSBundle loadNibNamed:@"ConnectionErrorDialog" owner:self];
+}
+
+
+/*
+ * Override the normal connection method, extending it to also store details of the
+ * current connection to allow reconnection as necessary. This also sets the connection timeout
+ * - used for pings, not for long-running commands.
+ */
+- (BOOL) connectWithLogin:(NSString *) login password:(NSString *) pass host:(NSString *) host port:(int) port socket:(NSString *) socket
+{
+ if (connectionLogin) [connectionLogin release];
+ if (login) connectionLogin = [[NSString alloc] initWithString:login];
+ if (connectionPassword) [connectionPassword release];
+ if (pass) connectionPassword = [[NSString alloc] initWithString:pass];
+ if (connectionHost) [connectionHost release];
+ if (host) connectionHost = [[NSString alloc] initWithString:host];
+ connectionPort = port;
+ if (connectionSocket) [connectionSocket release];
+ if (socket) connectionSocket = [[NSString alloc] initWithString:socket];
+
+ if (mConnection != NULL) {
+ unsigned int connectionTimeout = SP_CONNECTION_TIMEOUT;
+ mysql_options(mConnection, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&connectionTimeout);
+ }
+
+ return [super connectWithLogin:login password:pass host:host port:port socket:socket];
+}
+
+
+/*
+ * Override the stored disconnection method to ensure that disconnecting clears stored details.
+ */
+- (void) disconnect
+{
+ [super disconnect];
+
+ if (connectionLogin) [connectionLogin release];
+ connectionLogin = nil;
+ if (connectionPassword) [connectionPassword release];
+ connectionPassword = nil;
+ if (connectionHost) [connectionHost release];
+ connectionHost = nil;
+ connectionPort = 0;
+ if (connectionSocket) [connectionSocket release];
+ connectionSocket = nil;
+}
+
+
+/*
+ * 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;
+ 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"]];
+ }
+
+ // Close the connection if it exists.
+ if (mConnected) {
+ mysql_close(mConnection);
+ mConnection = NULL;
+ }
+ mConnected = NO;
+
+ // 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
+ unsigned int connectionTimeout = SP_CONNECTION_TIMEOUT;
+ mysql_options(mConnection, MYSQL_OPT_CONNECT_TIMEOUT, (const void *)&connectionTimeout);
+
+ // Attempt to reestablish the connection - using own method so everything gets set up as standard.
+ // Will store the supplied details again, which isn't a problem.
+ [self connectWithLogin:connectionLogin password:connectionPassword host:connectionHost port:connectionPort socket:connectionSocket];
+ }
+
+ // 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:@"SET NAMES '%@'", currentEncoding]];
+ [self setEncoding:[CMMCPConnection encodingForMySQLEncoding:[currentEncoding UTF8String]]];
+ }
+ } 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;
+}
+
+
+/*
+ * Ends and existing modal session
+ */
+- (IBAction) closeSheet:(id)sender
+{
+ [NSApp stopModalWithCode:[sender tag]];
+}
+
/*
Gets a proper NSStringEncoding according to the given MySQL charset.
@@ -92,7 +273,7 @@ WARNING : incomplete implementation. Please, send your fixes.
if (!strncmp(mysqlEncoding, "sjis", 4)) {
return NSShiftJISStringEncoding;
}
-
+
// default to iso latin 1, even if it is not exact (throw an exception?)
NSLog(@"warning: unknown encoding %s! falling back to latin1.", mysqlEncoding);
return NSISOLatin1StringEncoding;
@@ -101,7 +282,10 @@ WARNING : incomplete implementation. Please, send your fixes.
/*
- modified version of queryString to be used in sequel-pro
+ * 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
{
@@ -109,30 +293,29 @@ WARNING : incomplete implementation. Please, send your fixes.
const char *theCQuery = [self cStringFromString:query];
int theQueryCode;
- // check connection
- if (![self checkConnection]) {
- NSLog(@"Connection was gone, but should be reestablished now!");
- }
+ // If no connection is present, return nil.
+ if (!mConnected) return nil;
+
+ // 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
+ // Inform the delegate about the query
if (delegate && [delegate respondsToSelector:@selector(willQueryString:)]) {
[delegate willQueryString:query];
}
if (0 == (theQueryCode = mysql_query(mConnection, theCQuery))) {
if (mysql_field_count(mConnection) != 0) {
- // use CMMCPResult instad of MCPResult
+
+ // Use CMMCPResult instad of MCPResult
theResult = [[CMMCPResult alloc] initWithMySQLPtr:mConnection encoding:mEncoding timeZone:mTimeZone];
} else {
return nil;
}
} else {
-// NSLog (@"Problem in queryString error code is : %d, query is : %s -in ObjC : %@-\n", theQueryCode, theCQuery, query);
-// NSLog(@"Error message is : %@\n", [self getLastErrorMessage]);
-// theResult = [theResult init]; // Old version...
-// theResult = nil;
-
- // inform the delegate about errors
+
+ // Inform the delegate about errors
if (delegate && [delegate respondsToSelector:@selector(queryGaveError:)]) {
[delegate queryGaveError:[self getLastErrorMessage]];
}
@@ -142,6 +325,50 @@ WARNING : incomplete implementation. Please, send your fixes.
return [theResult autorelease];
}
+static void sigalarm(int segnum) {
+ NSLog(@"BOOOOYAAAAA");
+}
+/*
+ * 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
+{
+ if (!mConnected) return NO;
+
+ BOOL connectionVerified = FALSE;
+
+ // 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];
+ }
+ }
+
+ return connectionVerified;
+}
+
- (void)setDelegate:(id)object
{
delegate = object;
@@ -156,7 +383,7 @@ WARNING : incomplete implementation. Please, send your fixes.
NSArray *theRow;
id theTZName;
NSTimeZone *theTZ;
-
+
[theSessionTZ dataSeek:1ULL];
theRow = [theSessionTZ fetchRowAsArray];
theTZName = [theRow objectAtIndex:1];
@@ -176,7 +403,7 @@ WARNING : incomplete implementation. Please, send your fixes.
theTZName = [self stringWithText:theTZName];
}
}
-
+
if (theTZName) { // Old versions of the server does not support there own time zone ?
theTZ = [NSTimeZone timeZoneWithName:theTZName];
} else {
@@ -195,7 +422,7 @@ WARNING : incomplete implementation. Please, send your fixes.
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];
@@ -204,4 +431,71 @@ WARNING : incomplete implementation. Please, send your fixes.
return mTimeZone;
}
-@end
+
+/*
+ * 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 date];
+ 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(SP_CONNECTION_TIMEOUT+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 && ([[NSDate date] timeIntervalSinceDate:startDate] < 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);
+
+
+ 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);
+}
+
+@end \ No newline at end of file