[gparted] Add Partition object resizing method Partition*::resize() (#774818)

[Curtis Gedak <gedakc src gnome org>]

commit 08e4ba4ecab2325be6542ff60530408bc245e493
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Sun Dec 4 20:44:46 2016 +0000

    Add Partition object resizing method Partition*::resize() (#774818)
    
    Add a resize() method to both Partition and PartitionLUKS classes.  They
    take a reference Partition object, and update the position, size and
    file system usage of *this Partition to match.  This is ready for taking
    a partition returned from Resize/Move dialog and applying the change.
    
    Bug 774818 - Implement LUKS read-write actions NOT requiring a
                 passphrase

 include/Partition.h     |    1 +
 include/PartitionLUKS.h |    1 +
 src/Partition.cc        |   14 ++++++++++++++
 src/PartitionLUKS.cc    |   14 ++++++++++++++
 4 files changed, 30 insertions(+), 0 deletions(-)
---
diff --git a/include/Partition.h b/include/Partition.h
index eb70724..b9b1414 100644
--- a/include/Partition.h
+++ b/include/Partition.h
@@ -90,6 +90,7 @@ public:
        virtual Sector get_sectors_unused() const;
        virtual Sector get_sectors_unallocated() const;
        void get_usage_triple( int imax, int & i1, int & i2, int & i3 ) const ;
+       virtual void resize( const Partition & new_size );
 
        void Set_Unallocated( const Glib::ustring & device_path,
                              bool whole_device,
diff --git a/include/PartitionLUKS.h b/include/PartitionLUKS.h
index 7dd7654..7acc86b 100644
--- a/include/PartitionLUKS.h
+++ b/include/PartitionLUKS.h
@@ -49,6 +49,7 @@ public:
        virtual Sector get_sectors_used() const;
        virtual Sector get_sectors_unused() const;
        virtual Sector get_sectors_unallocated() const;
+       virtual void resize( const Partition & new_size );
        virtual bool have_messages() const;
        virtual std::vector<Glib::ustring> get_messages() const;
        virtual void clear_messages();
diff --git a/src/Partition.cc b/src/Partition.cc
index 93d0dbb..723e823 100644
--- a/src/Partition.cc
+++ b/src/Partition.cc
@@ -163,6 +163,20 @@ Sector Partition::get_sectors_unallocated() const
                return sectors_unallocated ;
 }
 
+// Update size, position and FS usage from new_size.
+void Partition::resize( const Partition & new_size )
+{
+       sector_start      = new_size.sector_start;
+       sector_end        = new_size.sector_end;
+       alignment         = new_size.alignment;
+       free_space_before = new_size.free_space_before;
+       strict_start      = new_size.strict_start;
+
+       Sector fs_size   = new_size.sectors_used + new_size.sectors_unused;
+       Sector fs_unused = fs_size - new_size.sectors_used;
+       set_sector_usage( fs_size, fs_unused );
+}
+
 void Partition::Set_Unallocated( const Glib::ustring & device_path,
                                  bool whole_device,
                                  Sector sector_start,
diff --git a/src/PartitionLUKS.cc b/src/PartitionLUKS.cc
index e927676..3ac6756 100644
--- a/src/PartitionLUKS.cc
+++ b/src/PartitionLUKS.cc
@@ -196,6 +196,20 @@ Sector PartitionLUKS::get_sectors_unallocated() const
        return Partition::get_sectors_unallocated();
 }
 
+// Update size, position and FS usage from new_size.
+void PartitionLUKS::resize( const Partition & new_size )
+{
+       Partition::resize( new_size );
+       // As per discussion in luks::set_used_sectors() LUKS itself is always 100% used.
+       set_sector_usage( get_sector_length(), 0LL );
+
+       Sector mapping_size = get_sector_length() - header_size;
+       encrypted.sector_end = mapping_size - 1LL;
+
+       Sector fs_unused = mapping_size - encrypted.sectors_used;
+       encrypted.set_sector_usage( mapping_size, fs_unused );
+}
+
 bool PartitionLUKS::have_messages() const
 {
        if ( busy )