Create and use general find_extended_partition() function

The Operation class already provided find_index_extended() method and
 was used in the Operation and derived classes where required.  It
returns the index to the extended partition in the PartitionVector
object, or -1 when no extended partition exists.

There were several cases of the same functionality being open coded in
GParted_Core and Win_GParted.  Therefore move the implementation to
find_extended_partition() in PartitionVector compilation unit and use
this implementation everywhere.

include/Operation.h

@@ -66,7 +66,6 @@ public:
 protected:
 	int find_index_original( const PartitionVector & partitions );
 	int find_index_new( const PartitionVector & partitions );
-	int find_index_extended( const PartitionVector & partitions );
 	void insert_unallocated( PartitionVector & partitions,
 	                         Sector start, Sector end, Byte_Value sector_size, bool inside_extended );
 	void substitute_new( PartitionVector & partitions );

include/PartitionVector.h

@@ -77,6 +77,8 @@ private:
 	std::vector<Partition *> v;
 };
 
+int find_extended_partition( const PartitionVector & partitions );
+
 } //GParted
 
 #endif /* GPARTED_PARTITIONVECTOR_H */

src/GParted_Core.cc

@@ -380,17 +380,10 @@ bool GParted_Core::snap_to_mebibyte( const Device & device, Partition & partitio
 		//  available for any following logical partition Extended Boot Record
 		if ( partition .type == TYPE_EXTENDED )
 		{
-			//Locate the extended partition that contains the logical partitions.
-			int index_extended = -1 ;
-			for ( unsigned int t = 0 ; t < device .partitions .size() ; t++ )
-			{
-				if ( device .partitions[ t ] .type == TYPE_EXTENDED )
-					index_extended = t ;
-			}
-
 			//If there is logical partition that starts less than 2 sectors
 			//  from the start of this partition, then reserve a mebibyte for the EBR.
-			if ( index_extended != -1 )
+			int index_extended = find_extended_partition( device.partitions );
+			if ( index_extended >= 0 )
 			{
 				for ( unsigned int t = 0; t < device .partitions[ index_extended ] .logicals .size(); t++ )
 				{
@@ -420,17 +413,10 @@ bool GParted_Core::snap_to_mebibyte( const Device & device, Partition & partitio
 	//  required for a following logical partition Extended Boot Record
 	if ( partition .type == TYPE_LOGICAL )
 	{
-		//Locate the extended partition that contains the logical partitions.
-		int index_extended = -1 ;
-		for ( unsigned int t = 0 ; t < device .partitions .size() ; t++ )
-		{
-			if ( device .partitions[ t ] .type == TYPE_EXTENDED )
-				index_extended = t ;
-		}
-
 		//If there is a following logical partition that starts less than 2 sectors from
 		//  the end of this partition, then reserve at least a mebibyte for the EBR.
-		if ( index_extended != -1 )
+		int index_extended = find_extended_partition( device.partitions );
+		if ( index_extended >= 0 )
 		{
 			for ( unsigned int t = 0; t < device .partitions[ index_extended ] .logicals .size(); t++ )
 			{

src/Operation.cc

@@ -81,15 +81,6 @@ int Operation::find_index_new( const PartitionVector & partitions )
 	return -1;
 }
 
-int Operation::find_index_extended( const PartitionVector & partitions )
-{
-	for ( unsigned int t = 0 ; t < partitions .size() ; t++ )
-		if ( partitions[ t ] .type == GParted::TYPE_EXTENDED )
-			return t ;
-
-	return -1 ;
-}
-
 void Operation::insert_unallocated( PartitionVector & partitions,
                                     Sector start, Sector end, Byte_Value sector_size, bool inside_extended )
 {
@@ -110,7 +101,7 @@ void Operation::substitute_new( PartitionVector & partitions )
 
 	if ( partition_original->inside_extended )
 	{
-		index_extended = find_index_extended( partitions );
+		index_extended = find_extended_partition( partitions );
 		if ( index_extended >= 0 )
 		{
 			index = find_index_original( partitions[index_extended].logicals );
@@ -146,7 +137,7 @@ void Operation::insert_new( PartitionVector & partitions )
 
 	if ( partition_new->inside_extended )
 	{
-		index_extended = find_index_extended( partitions );
+		index_extended = find_extended_partition( partitions );
 		if ( index_extended >= 0 )
 		{
 			index = find_index_new( partitions[index_extended].logicals );

src/OperationDelete.cc

@@ -61,8 +61,7 @@ void OperationDelete::apply_to_visual( PartitionVector & partitions )
 
 	if ( partition_original->inside_extended )
 	{
-		index_extended = find_index_extended( partitions ) ;
+		index_extended = find_extended_partition( partitions );
-		
 		if ( index_extended >= 0 )
 		{
 			index = find_index_original( partitions[ index_extended ] .logicals ) ;

src/OperationResizeMove.cc

@@ -151,8 +151,7 @@ void OperationResizeMove::apply_normal_to_visual( PartitionVector & partitions )
 
 	if ( partition_original->inside_extended )
 	{
-		index_extended = find_index_extended( partitions ) ;
+		index_extended = find_extended_partition( partitions );
-			
 		if ( index_extended >= 0 )
 		{
 			index = find_index_original( partitions[ index_extended ] .logicals ) ;
@@ -191,13 +190,12 @@ void OperationResizeMove::apply_extended_to_visual( PartitionVector & partitions
 	int index_extended;
 
 	//stuff OUTSIDE extended partition
-	index_extended = find_index_extended( partitions ) ;
+	index_extended = find_extended_partition( partitions );
-		
 	if ( index_extended >= 0 )
 	{
 		remove_adjacent_unallocated( partitions, index_extended ) ;
-		
+
-		index_extended = find_index_extended( partitions ) ;
+		index_extended = find_extended_partition( partitions );
 		if ( index_extended >= 0 )
 		{
 			partitions[index_extended].sector_start = partition_new->sector_start;
@@ -208,8 +206,7 @@ void OperationResizeMove::apply_extended_to_visual( PartitionVector & partitions
 	}
 	
 	//stuff INSIDE extended partition
-	index_extended = find_index_extended( partitions ) ;
+	index_extended = find_extended_partition( partitions );
-	
 	if ( index_extended >= 0 )
 	{
 		if ( partitions[ index_extended ] .logicals .size() > 0 &&

src/PartitionVector.cc

@@ -90,4 +90,13 @@ void PartitionVector::replace_at( size_type n, const Partition * partition )
 	v[n] = p;
 }
 
+// Return index of the extended partition or -1 when not found
+int find_extended_partition( const PartitionVector & partitions )
+{
+	for ( unsigned int i = 0 ; i < partitions.size() ; i ++ )
+		if ( partitions[i].type == TYPE_EXTENDED )
+			return (int)i;
+	return -1;
+}
+
 } //GParted

src/Win_GParted.cc

@@ -1783,13 +1783,9 @@ void Win_GParted::activate_resize()
 	g_assert( valid_display_partition_ptr( selected_partition_ptr ) );  // Bug: Not pointing at a valid display partition object
 
 	PartitionVector * display_partitions_ptr = &display_partitions;
-	if ( selected_partition_ptr->type == TYPE_LOGICAL )
+	int index_extended = find_extended_partition( display_partitions );
-	{
+	if ( index_extended >= 0 )
-		unsigned int ext = 0 ;
+		display_partitions_ptr = &display_partitions[index_extended].logicals;
-		while ( ext < display_partitions.size() && display_partitions[ext].type != TYPE_EXTENDED )
-			ext++;
-		display_partitions_ptr = &display_partitions[ext].logicals;
-	}
 
 	FS fs_cap = gparted_core.get_fs( selected_partition_ptr->get_filesystem_partition().filesystem );
 	Partition * working_ptn;
@@ -2085,15 +2081,7 @@ void Win_GParted::activate_new()
 		// Check if an extended partition already exist; so that the dialog can
 		// decide whether to allow the creation of the only extended partition
 		// type or not.
-		bool any_extended = false;
+		bool any_extended = ( find_extended_partition( display_partitions ) >= 0 );
-		for ( unsigned int i = 0 ; i < display_partitions.size() ; i ++ )
-		{
-			if ( display_partitions[i].type == TYPE_EXTENDED )
-			{
-				any_extended = true;
-				break;
-			}
-		}
 		Dialog_Partition_New dialog( devices[current_device],
 		                             *selected_partition_ptr,
 		                             any_extended,