[gparted] Use BlockSpecial objects in btrfs member cache (#767842)

[Curtis Gedak <gedakc src gnome org>]

commit abee66484fb355a1bac5b03f361bab7435df867b
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Sat Jun 25 08:29:17 2016 +0100

    Use BlockSpecial objects in btrfs member cache (#767842)
    
    There are no known errors which affect the remaining caches in GParted.
    However those caches which compare block special devices will be changed
    to use BlockSpecial objects so comparison is by major, minor device
    number rather than by name.
    
    Change btrfs member cache loaded from "btrfs filesystem show" output to
    use BlockSpecial objects.
    
    Bug 767842 - File system usage missing when tools report alternate block
                 device names

 include/btrfs.h |    5 +++--
 src/btrfs.cc    |   38 +++++++++++++++++++++++---------------
 2 files changed, 26 insertions(+), 17 deletions(-)
---
diff --git a/include/btrfs.h b/include/btrfs.h
index f09638e..56ee4bf 100644
--- a/include/btrfs.h
+++ b/include/btrfs.h
@@ -20,6 +20,7 @@
 #define GPARTED_BTRFS_H
 
 #include "../include/FileSystem.h"
+#include "../include/BlockSpecial.h"
 #include "../include/Partition.h"
 
 namespace GParted
@@ -27,8 +28,8 @@ namespace GParted
 
 struct BTRFS_Device
 {
-       int                             devid ;
-       std::vector<Glib::ustring>      members ;
+       int                       devid;
+       std::vector<BlockSpecial> members;
 } ;
 
 class btrfs : public FileSystem
diff --git a/src/btrfs.cc b/src/btrfs.cc
index 9c8d458..60e6551 100644
--- a/src/btrfs.cc
+++ b/src/btrfs.cc
@@ -17,6 +17,7 @@
 
 
 #include "../include/btrfs.h"
+#include "../include/BlockSpecial.h"
 #include "../include/GParted_Core.h"
 #include "../include/Partition.h"
 
@@ -28,14 +29,15 @@ namespace GParted
 bool btrfs_found = false ;
 bool resize_to_same_size_fails = true ;
 
-//Cache of required btrfs file system device information by device
-//  E.g. For a single device btrfs on /dev/sda2 and a three device btrfs
-//       on /dev/sd[bcd]1 the cache would be:
-//  btrfs_device_cache["/dev/sda2"] = {devid=1, members=["/dev/sda2"]}
-//  btrfs_device_cache["/dev/sdb1"] = {devid=1, members=["/dev/sdd1", "/dev/sdc1", "/dev/sdb1"]}
-//  btrfs_device_cache["/dev/sdc1"] = {devid=2, members=["/dev/sdd1", "/dev/sdc1", "/dev/sdb1"]}
-//  btrfs_device_cache["/dev/sdd1"] = {devid=3, members=["/dev/sdd1", "/dev/sdc1", "/dev/sdb1"]}
-std::map<Glib::ustring, BTRFS_Device> btrfs_device_cache ;
+// Cache of required btrfs file system device information by device
+// E.g. For a single device btrfs on /dev/sda2 and a three device btrfs
+//      on /dev/sd[bcd]1 the cache would be as follows.  (Note that
+//      BS(str) is short hand for constructor BlockSpecial(str)).
+//  btrfs_device_cache[BS("/dev/sda2")] = {devid=1, members=[BS("/dev/sda2")]}
+//  btrfs_device_cache[BS("/dev/sdb1")] = {devid=1, members=[BS("/dev/sdd1"), BS("/dev/sdc1"), 
BS("/dev/sdb1")]}
+//  btrfs_device_cache[BS("/dev/sdc1")] = {devid=2, members=[BS("/dev/sdd1"), BS("/dev/sdc1"), 
BS("/dev/sdb1")]}
+//  btrfs_device_cache[BS("/dev/sdd1")] = {devid=3, members=[BS("/dev/sdd1"), BS("/dev/sdc1"), 
BS("/dev/sdb1")]}
+std::map<BlockSpecial, BTRFS_Device> btrfs_device_cache;
 
 FS btrfs::get_filesystem_support()
 {
@@ -460,15 +462,18 @@ Glib::ustring btrfs::get_mount_device( const Glib::ustring & path )
        }
 
        for ( unsigned int i = 0 ; i < btrfs_dev .members .size() ; i ++ )
-               if ( GParted_Core::is_dev_mounted( btrfs_dev .members[ i ] ) )
-                       return btrfs_dev .members[ i ] ;
+               if ( GParted_Core::is_dev_mounted( btrfs_dev.members[i].m_name ) )
+                       return btrfs_dev.members[i].m_name;
        return "" ;
 }
 
 std::vector<Glib::ustring> btrfs::get_members( const Glib::ustring & path )
 {
        BTRFS_Device btrfs_dev = get_cache_entry( path ) ;
-       return btrfs_dev .members ;
+       std::vector<Glib::ustring> membs;
+       for ( unsigned int i = 0 ; i < btrfs_dev.members.size() ; i ++ )
+               membs.push_back( btrfs_dev.members[i].m_name );
+       return membs;
 }
 
 //Private methods
@@ -476,7 +481,7 @@ std::vector<Glib::ustring> btrfs::get_members( const Glib::ustring & path )
 //Return btrfs device cache entry, incrementally loading cache as required
 const BTRFS_Device & btrfs::get_cache_entry( const Glib::ustring & path )
 {
-       std::map<Glib::ustring, BTRFS_Device>::const_iterator bd_iter = btrfs_device_cache .find( path ) ;
+       std::map<BlockSpecial, BTRFS_Device>::const_iterator bd_iter = btrfs_device_cache.find( BlockSpecial( 
path ) );
        if ( bd_iter != btrfs_device_cache .end() )
                return bd_iter ->second ;
 
@@ -511,15 +516,18 @@ const BTRFS_Device & btrfs::get_cache_entry( const Glib::ustring & path )
                offset = index + 5 ;  //Next find starts immediately after current "devid"
        }
        //Add cache entries for all found devices
+       std::vector<BlockSpecial> bs_list;
+       for ( unsigned int i = 0 ; i < path_list.size() ; i ++ )
+               bs_list.push_back( BlockSpecial( path_list[i] ) );
        for ( unsigned int i = 0 ; i < devid_list .size() ; i ++ )
        {
                BTRFS_Device btrfs_dev ;
                btrfs_dev .devid = devid_list[ i ] ;
-               btrfs_dev .members = path_list ;
-               btrfs_device_cache[ path_list[ i ] ] = btrfs_dev ;
+               btrfs_dev.members = bs_list;
+               btrfs_device_cache[ BlockSpecial( path_list[i] ) ] = btrfs_dev;
        }
 
-       bd_iter = btrfs_device_cache .find( path ) ;
+       bd_iter = btrfs_device_cache.find( BlockSpecial( path ) );
        if ( bd_iter != btrfs_device_cache .end() )
                return bd_iter ->second ;