Additional debug code for #2163

Author: dmoagx

Diff for: Source/SPDataStorage.h

@@ -47,6 +47,9 @@
 
 	NSUInteger numberOfColumns;
 	NSUInteger editedRowCount;
+	
+	NSString *_debugInfo;
+	uint64_t _debugTime;
 }
 
 /* Setting result store */

Diff for: Source/SPDataStorage.m

@@ -32,13 +32,18 @@
 #import "SPObjectAdditions.h"
 #import <SPMySQL/SPMySQLStreamingResultStore.h>
 #include <stdlib.h>
+#include <mach/mach_time.h>
 
 @interface SPDataStorage (Private_API)
 
 - (void) _checkNewRow:(NSMutableArray *)aRow;
+- (void)_recordClearingUnloadedColumnsAt:(uint64_t)now from:(NSArray *)callStack;
+- (void)_assesUnloadedColumnsIsSet;
 
 @end
 
+static uint64_t _elapsedMilliSecondsSinceAbsoluteTime(uint64_t comparisonTime);
+
 @implementation SPDataStorage
 
 static inline NSMutableArray* SPDataStorageGetEditedRow(NSPointerArray* rowStore, NSUInteger rowIndex)
@@ -60,7 +65,13 @@ - (void) setDataStorage:(SPMySQLStreamingResultStore *)newDataStorage updatingEx
 	NSUInteger i;
 	editedRowCount = 0;
 	SPClear(editedRows);
-	if (unloadedColumns) free(unloadedColumns), unloadedColumns = NULL;
+	@synchronized(self) {
+		if (unloadedColumns) {
+			[self _recordClearingUnloadedColumnsAt:mach_absolute_time() from:[NSThread callStackSymbols]];
+			free(unloadedColumns), unloadedColumns = NULL;
+		}
+	}
+	
 
 	if (dataStorage) {
 
@@ -81,9 +92,11 @@ - (void) setDataStorage:(SPMySQLStreamingResultStore *)newDataStorage updatingEx
 		[self resultStoreDidFinishLoadingData:dataStorage];
 	}
 
-	unloadedColumns = calloc(numberOfColumns, sizeof(BOOL));
-	for (i = 0; i < numberOfColumns; i++) {
-		unloadedColumns[i] = NO;
+	@synchronized(self) {
+		unloadedColumns = calloc(numberOfColumns, sizeof(BOOL));
+		for (i = 0; i < numberOfColumns; i++) {
+			unloadedColumns[i] = NO;
+		}
 	}
 }
 
@@ -110,10 +123,12 @@ - (NSMutableArray *) rowContentsAtIndex:(NSUInteger)anIndex
 	NSMutableArray *dataArray = SPMySQLResultStoreGetRow(dataStorage, anIndex);
 
 	// Modify unloaded cells as appropriate
-	for (NSUInteger i = 0; i < numberOfColumns; i++) {
-		NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-		if (unloadedColumns[i]) {
-			CFArraySetValueAtIndex((CFMutableArrayRef)dataArray, i, [SPNotLoaded notLoaded]);
+	@synchronized(self) {
+		[self _assesUnloadedColumnsIsSet];
+		for (NSUInteger i = 0; i < numberOfColumns; i++) {
+			if (unloadedColumns[i]) {
+				CFArraySetValueAtIndex((CFMutableArrayRef)dataArray, i, [SPNotLoaded notLoaded]);
+			}
 		}
 	}
 
@@ -140,9 +155,11 @@ - (id) cellDataAtRow:(NSUInteger)rowIndex column:(NSUInteger)columnIndex
 	}
 
 	// If the specified column is not loaded, return a SPNotLoaded reference
-	NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-	if (unloadedColumns[columnIndex]) {
-		return [SPNotLoaded notLoaded];
+	@synchronized(self) {
+		[self _assesUnloadedColumnsIsSet];
+		if (unloadedColumns[columnIndex]) {
+			return [SPNotLoaded notLoaded];
+		}
 	}
 
 	// Return the content
@@ -175,9 +192,11 @@ - (id) cellPreviewAtRow:(NSUInteger)rowIndex column:(NSUInteger)columnIndex prev
 	}
 
 	// If the specified column is not loaded, return a SPNotLoaded reference
-	NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-	if (unloadedColumns[columnIndex]) {
-		return [SPNotLoaded notLoaded];
+	@synchronized(self) {
+		[self _assesUnloadedColumnsIsSet];
+		if (unloadedColumns[columnIndex]) {
+			return [SPNotLoaded notLoaded];
+		}
 	}
 
 	// Return the content
@@ -203,9 +222,11 @@ - (BOOL) cellIsNullOrUnloadedAtRow:(NSUInteger)rowIndex column:(NSUInteger)colum
 		[NSException raise:NSRangeException format:@"Requested storage column (col %llu) beyond bounds (%llu)", (unsigned long long)columnIndex, (unsigned long long)numberOfColumns];
 	}
 
-	NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-	if (unloadedColumns[columnIndex]) {
-		return YES;
+	@synchronized(self) {
+		[self _assesUnloadedColumnsIsSet];
+		if (unloadedColumns[columnIndex]) {
+			return YES;
+		}
 	}
 
 	return [dataStorage cellIsNullAtRow:rowIndex column:columnIndex];
@@ -236,10 +257,12 @@ - (NSUInteger)countByEnumeratingWithState:(NSFastEnumerationState *)state object
 		targetRow = SPMySQLResultStoreGetRow(dataStorage, state->state);
 
 		// Modify unloaded cells as appropriate
-		for (NSUInteger i = 0; i < numberOfColumns; i++) {
-			NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-			if (unloadedColumns[i]) {
-				CFArraySetValueAtIndex((CFMutableArrayRef)targetRow, i, [SPNotLoaded notLoaded]);
+		@synchronized(self) {
+			[self _assesUnloadedColumnsIsSet];
+			for (NSUInteger i = 0; i < numberOfColumns; i++) {
+				if (unloadedColumns[i]) {
+					CFArraySetValueAtIndex((CFMutableArrayRef)targetRow, i, [SPNotLoaded notLoaded]);
+				}
 			}
 		}
 	}
@@ -397,8 +420,10 @@ - (void) setColumnAsUnloaded:(NSUInteger)columnIndex
 	if (columnIndex >= numberOfColumns) {
 		[NSException raise:NSRangeException format:@"Invalid column set as unloaded; requested column index (%llu) beyond bounds (%llu)", (unsigned long long)columnIndex, (unsigned long long)numberOfColumns];
 	}
-	NSAssert(unloadedColumns != NULL, @"unloadedColumns not loaded!");
-	unloadedColumns[columnIndex] = YES;
+	@synchronized(self) {
+		[self _assesUnloadedColumnsIsSet];
+		unloadedColumns[columnIndex] = YES;
+	}
 }
 
 #pragma mark - Basic information
@@ -451,15 +476,29 @@ - (id) init {
 
 		numberOfColumns = 0;
 		editedRowCount = 0;
+		
+		_debugInfo = nil;
+		_debugTime = mach_absolute_time();
 	}
 	return self;
 }
 
 - (void) dealloc {
 	SPClear(dataStorage);
 	SPClear(editedRows);
-	if (unloadedColumns) free(unloadedColumns), unloadedColumns = NULL;
-
+	@synchronized(self) {
+		if (unloadedColumns) {
+			[self _recordClearingUnloadedColumnsAt:mach_absolute_time() from:[NSThread callStackSymbols]];
+			free(unloadedColumns), unloadedColumns = NULL;
+		}
+	}
+	// this is very very unlikely, but if another thread had been waiting on the lock
+	// right before we free'd unloadedColumns, it should get it before we can release
+	// _debugInfo, too.
+	@synchronized(self) {
+		SPClear(_debugInfo);
+	}
+	
 	[super dealloc];
 }
 
@@ -474,5 +513,37 @@ - (void) _checkNewRow:(NSMutableArray *)aRow
 	}
 }
 
+// DO NOT CALL THIS METHOD UNLESS YOU CURRENTLY HAVE A LOCK ON SELF!!!
+- (void)_recordClearingUnloadedColumnsAt:(uint64_t)now from:(NSArray *)callStack
+{
+	_debugTime = now;
+	SPClear(_debugInfo);
+	_debugInfo = [[NSString alloc] initWithFormat:@"Thread: %@, Stack: %@",[NSThread currentThread],callStack];
+}
+
+// DO NOT CALL THIS METHOD UNLESS YOU CURRENTLY HAVE A LOCK ON SELF!!!
+- (void)_assesUnloadedColumnsIsSet
+{
+	if(unloadedColumns != NULL)
+		return;
+	
+	uint64_t timeDiff = _elapsedMilliSecondsSinceAbsoluteTime(_debugTime);
+	
+	NSString *msg;
+	if(!_debugInfo)
+		msg = [NSString stringWithFormat:@"unloadedColumns is not set and never has been since the object was created %llums ago.",timeDiff];
+	else
+		msg = [NSString stringWithFormat:@"unloadedColumns was last cleared %llums ago at %@",timeDiff,_debugInfo];
+	
+	@throw [NSException exceptionWithName:NSInternalInconsistencyException reason:msg userInfo:nil];
+}
 
 @end
+
+static uint64_t _elapsedMilliSecondsSinceAbsoluteTime(uint64_t comparisonTime)
+{
+	uint64_t elapsedTime_t = mach_absolute_time() - comparisonTime;
+	Nanoseconds elapsedTime = AbsoluteToNanoseconds(*(AbsoluteTime *)&(elapsedTime_t));
+	
+	return (UnsignedWideToUInt64(elapsedTime) / 1000000ULL);
+}