[gparted] Simplify Device object to a single path (#767842)

[Curtis Gedak <gedakc src gnome org>]

commit 902afaa010489d748927da1d4e779018d932d439
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Thu Jun 2 07:49:53 2016 +0100

    Simplify Device object to a single path (#767842)
    
    Background
    
    GParted stored a list of paths for Device and Partition objects.  It
    sorted this list [1][2] and treated the first specially as that is what
    get_path() returned and was used almost everywhere; with the file system
    specific tools, looked up in various *_Info caches, etc.
    
    [1] Device::add_path(), ::add_paths()
    [2] Partition::add_path(), ::add_paths()
    
    Mount point display [3] was the only bit of GParted which really worked
    with the path list.  Busy file system detection [4] just used the path
    provided by libparted, or for LUKS /dev/mapper/* names.  It checked that
    single path against the mounted file systems found from /proc/mounts,
    expanded with additional block device names when symlinks were
    encountered.
    
    [3] GParted_Core::set_mountpoints() -> set_mountpoints_helper()
    [4] GParted_Core::set_device_partitions() -> is_busy()
        GParted_Core::set_device_one_partition() -> is_busy()
        GParted_Core::set_luks_partition() -> is_busy()
    
    Having the first path, by sort order, treated specially by being used
    everywhere and virtually ignoring the others was wrong, complicated to
    remember and difficult code with.  As all the additional paths were
    virtually unused and made no difference, remove them.  The "improved
    detection of mountpoins, free space, etc.." benefit from commit [5]
    doesn't seem to exist.  Therefore simplify to a single path for Device
    and Partition objects.
    
    [5] commit 6d8b169e734e1ecb191d5164689f24400010a7b4
        changed the way devices and partitions store their device paths.
        Instead of holding a 'realpath' and a symbolic path we store paths
        in a list.  This allows for improved detection of mountpoins, free
        space, etc..
    
    This patch
    
    Simplify the Device object from a vector of paths to a single path.
    Remove add_paths() and get_paths() methods.  Keep add_path() and
    get_path() for now.
    
    Bug 767842 - File system usage missing when tools report alternate block
                 device names

 include/Device.h    |    8 +-------
 src/Device.cc       |   46 ++++------------------------------------------
 src/GParted_Core.cc |    1 -
 src/Win_GParted.cc  |    4 ++--
 4 files changed, 7 insertions(+), 52 deletions(-)
---
diff --git a/include/Device.h b/include/Device.h
index 0112340..8c0ebcc 100644
--- a/include/Device.h
+++ b/include/Device.h
@@ -33,9 +33,7 @@ public:
 
        Device get_copy_without_partitions() const;
        void add_path( const Glib::ustring & path, bool clear_paths = false ) ;
-       void add_paths( const std::vector<Glib::ustring> & paths, bool clear_paths = false ) ;
        Glib::ustring get_path() const ;
-       std::vector<Glib::ustring> get_paths() const ;
        void enable_partition_naming( int length );  // > 0 => enable partition naming support
        bool partition_naming_supported() const;
        int get_max_partition_name_length() const;
@@ -59,11 +57,7 @@ public:
        bool readonly ; 
 
 private:
-       void sort_paths_and_remove_duplicates() ;
-
-       static bool compare_paths( const Glib::ustring & A, const Glib::ustring & B ) ;
-       
-       std::vector<Glib::ustring> paths ;
+       Glib::ustring path;
        int max_partition_name_length;  // > 0 => naming of partitions is supported on this device
 };
  
diff --git a/src/Device.cc b/src/Device.cc
index 96a79dd..687f461 100644
--- a/src/Device.cc
+++ b/src/Device.cc
@@ -27,7 +27,7 @@ Device::Device()
 
 void Device::Reset()
 {
-       paths .clear() ;
+       path.clear();
        partitions .clear() ;
        length = cylsize = 0 ;
        heads = sectors = cylinders = 0 ;
@@ -53,42 +53,19 @@ Device Device::get_copy_without_partitions() const
        new_device.max_prims                 = this->max_prims;
        new_device.highest_busy              = this->highest_busy;
        new_device.readonly                  = this->readonly;
-       new_device.paths                     = this->paths;
+       new_device.path                      = this->path;
        new_device.max_partition_name_length = this->max_partition_name_length;
        return new_device;                                    // (3) Return by value.
 }
 
 void Device::add_path( const Glib::ustring & path, bool clear_paths )
 {
-       if ( clear_paths )
-               paths .clear() ;
-
-       paths .push_back( path ) ;
-
-       sort_paths_and_remove_duplicates() ;
-}
-
-void Device::add_paths( const std::vector<Glib::ustring> & paths, bool clear_paths )
-{
-       if ( clear_paths )
-               this ->paths .clear() ;
-
-       this ->paths .insert( this ->paths .end(), paths .begin(), paths .end() ) ;
-
-       sort_paths_and_remove_duplicates() ;
+       this->path = path;
 }
 
 Glib::ustring Device::get_path() const
 {
-       if ( paths .size() > 0 )
-               return paths .front() ;
-
-       return "" ;
-}
-       
-std::vector<Glib::ustring> Device::get_paths() const
-{
-       return paths ;
+       return path;
 }
 
 void Device::enable_partition_naming( int max_length )
@@ -119,21 +96,6 @@ bool Device::operator!=( const Device & device ) const
        return ! ( *this == device ) ;
 }
        
-void Device::sort_paths_and_remove_duplicates()
-{
-       //remove duplicates
-       std::sort( paths .begin(), paths .end() ) ;
-       paths .erase( std::unique( paths .begin(), paths .end() ), paths .end() ) ;
-
-       //sort on length
-       std::sort( paths .begin(), paths .end(), compare_paths ) ;
-}
-
-bool Device::compare_paths( const Glib::ustring & A, const Glib::ustring & B )
-{
-       return A .length() < B .length() ;
-}
-
 Device::~Device()
 {
 }
diff --git a/src/GParted_Core.cc b/src/GParted_Core.cc
index 5b8c0a8..e840f85 100644
--- a/src/GParted_Core.cc
+++ b/src/GParted_Core.cc
@@ -278,7 +278,6 @@ void GParted_Core::set_devices_thread( std::vector<Device> * pdevices )
 
                        //device info..
                        temp_device .add_path( device_paths[ t ] ) ;
-                       temp_device .add_paths( pp_info .get_alternate_paths( temp_device .get_path() ) ) ;
 
                        temp_device .model      =       lp_device ->model ;
                        temp_device .length     =       lp_device ->length ;
diff --git a/src/Win_GParted.cc b/src/Win_GParted.cc
index 57b1df5..26d203d 100644
--- a/src/Win_GParted.cc
+++ b/src/Win_GParted.cc
@@ -692,8 +692,8 @@ void Win_GParted::Fill_Label_Device_Info( bool clear )
                device_info[ t++ ] ->set_text( devices[ current_device ] .model ) ;
                device_info[ t++ ] ->set_text( devices[current_device].serial_number );
                device_info[ t++ ] ->set_text( Utils::format_size( devices[ current_device ] .length, 
devices[ current_device ] .sector_size ) ) ;
-               device_info[ t++ ] ->set_text( Glib::build_path( "\n", devices[ current_device ] .get_paths() 
) ) ;
-               
+               device_info[ t++ ] ->set_text( devices[current_device].get_path() );
+
                //detailed info
                device_info[ t++ ] ->set_text( devices[ current_device ] .disktype ) ;
                device_info[ t++ ] ->set_text( Utils::num_to_str( devices[ current_device ] .heads ) );