From 71ff33d26cca61ee4b39924ca5a8d9a032a38e9f Mon Sep 17 00:00:00 2001 From: rowanbeentje Date: Tue, 31 Aug 2010 00:05:36 +0000 Subject: - Add connection checks before uses of mysql_hex_string and mysql_real_escape_string (which require an active connection). This addresses http://spbug.com/l/54 . --- Frameworks/MCPKit/MCPFoundationKit/MCPConnection.m | 67 ++++++++++++++++------ 1 file changed, 51 insertions(+), 16 deletions(-) (limited to 'Frameworks/MCPKit') diff --git a/Frameworks/MCPKit/MCPFoundationKit/MCPConnection.m b/Frameworks/MCPKit/MCPFoundationKit/MCPConnection.m index 65545f77..ab635e03 100644 --- a/Frameworks/MCPKit/MCPFoundationKit/MCPConnection.m +++ b/Frameworks/MCPKit/MCPFoundationKit/MCPConnection.m @@ -642,7 +642,7 @@ static BOOL sTruncateLongFieldInLogs = YES; - (BOOL)checkConnection { if (!mConnected) return NO; - + BOOL connectionVerified = FALSE; // Check whether the connection is still operational via a wrapped version of MySQL ping. @@ -1389,10 +1389,28 @@ void performThreadedKeepAlive(void *ptr) unsigned long theLength = [theData length]; char *theCEscBuffer = (char *)calloc(sizeof(char),(theLength*2) + 1); NSString *theReturn; -// unsigned long theEscapedLength; -// Using the mysql_hex_string function : (NO other solution found to be able to support blobs while using UTF-8 charset). -// theEscapedLength = mysql_hex_string(theCEscBuffer, theCDataBuffer, theLength); + // mysql_hex_string requires an active connection. + // If no connection is present, and no automatic reconnections can be made, return nil. + if (!mConnected && ![self checkConnection]) { + + // Inform the delegate that there is no connection available + if (delegate && [delegate respondsToSelector:@selector(noConnectionAvailable:)]) { + [delegate noConnectionAvailable:self]; + } + + return nil; + } + + // If thirty seconds have elapsed since the last query, check the connection. + // This minimises the impact of continuous additional connection checks, but handles + // most network issues and keeps high read/write timeouts for long queries. + if ([self timeConnected] - lastQueryExecutedAtTime > 30) { + if (![self checkConnection]) return nil; + lastQueryExecutedAtTime = [self timeConnected]; + } + + // Using the mysql_hex_string function : (NO other solution found to be able to support blobs while using UTF-8 charset). mysql_hex_string(theCEscBuffer, theCDataBuffer, theLength); theReturn = [NSString stringWithFormat:@"%s", theCEscBuffer]; free (theCEscBuffer); @@ -1406,8 +1424,6 @@ void performThreadedKeepAlive(void *ptr) { NSData *theCData = [theString dataUsingEncoding:stringEncoding allowLossyConversion:YES]; unsigned long theLength = [theCData length]; - // const char *theCStringBuffer = [self cStringFromString:theString]; - // unsigned long theLength = [theString length]; char *theCEscBuffer; NSString *theReturn; unsigned long theEscapedLength; @@ -1416,12 +1432,30 @@ void performThreadedKeepAlive(void *ptr) // In the mean time, no one should call this method on a nil string, the test should be done before by the user of this method. return @""; } + + // mysql_real_escape_string requires an active connection. + // If no connection is present, and no automatic reconnections can be made, return nil. + if (!mConnected && ![self checkConnection]) { + + // Inform the delegate that there is no connection available + if (delegate && [delegate respondsToSelector:@selector(noConnectionAvailable:)]) { + [delegate noConnectionAvailable:self]; + } + + return nil; + } - // theLength = strlen(theCStringBuffer); + // If thirty seconds have elapsed since the last query, check the connection. + // This minimises the impact of continuous additional connection checks, but handles + // most network issues and keeps high read/write timeouts for long queries. + if ([self timeConnected] - lastQueryExecutedAtTime > 30) { + if (![self checkConnection]) return nil; + lastQueryExecutedAtTime = [self timeConnected]; + } + theCEscBuffer = (char *)calloc(sizeof(char),(theLength * 2) + 1); theEscapedLength = mysql_real_escape_string(mConnection, theCEscBuffer, [theCData bytes], theLength); theReturn = [[NSString alloc] initWithData:[NSData dataWithBytes:theCEscBuffer length:theEscapedLength] encoding:stringEncoding]; - // theReturn = [self stringWithCString:theCEscBuffer]; free(theCEscBuffer); return [theReturn autorelease]; @@ -1515,8 +1549,8 @@ void performThreadedKeepAlive(void *ptr) // Reset the query cancelled boolean queryCancelled = NO; - // If no connection is present, return nil. - if (!mConnected) { + // If no connection is present, and no automatic reconnections can be made, return nil. + if (!mConnected && ![self checkConnection]) { // Write a log entry if ([delegate respondsToSelector:@selector(queryGaveError:connection:)]) [delegate queryGaveError:@"No connection available!" connection:self]; @@ -1536,13 +1570,14 @@ void performThreadedKeepAlive(void *ptr) [delegate willQueryString:query connection:self]; } - // If thirty seconds have elapsed since the last query, check the connection. This provides - // a balance between keeping high read/write timeouts for long queries, network issues, and - // minimising the impact of performing lots of additional checks. + // If thirty seconds have elapsed since the last query, check the connection. + // This minimises the impact of continuous additional connection checks, but handles + // most network issues and keeps high read/write timeouts for long queries. if ([self timeConnected] - lastQueryExecutedAtTime > 30 - && ![self checkConnection]) { - return nil; - } + && ![self checkConnection]) + { + return nil; + } // Derive the query string in the correct encoding NSData *d = NSStringDataUsingLossyEncoding(query, encoding, 1); -- cgit v1.2.3