[gparted/recognise-apfs: 5/8] Recognise APFS (Apple File System) (#23)

[Curtis Gedak <gedakc src gnome org>]

commit 69c1537a387cd885b58b689b6d1dc1cb517f0cfb
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Wed Nov 7 20:05:38 2018 +0000

    Recognise APFS (Apple File System) (#23)
    
    Just add detection of APFS using GParted's internal magic string
    detection.  It just matches 1 byte of the 2 byte object type and the
    4 byte magic field found in the super block [1].  See code comment for
    more details.
    
    Blkid has just gained recognition of APFS with util-linux v2.33 released
    06-Nov-2018 [2].
    
    This will write enough for GParted's simple internal detection to find
    APFS:
        # python -c '
        import sys
        sys.stdout.write("\0"*24 + "\1\0" + "\0"*6 + "NXSB")
        ' > /dev/sdb1
    
    [1] Apple File System Reference
        https://developer.apple.com/support/apple-file-system/Apple-File-System-Reference.pdf
    
    [2] [ANNOUNCE] util-linux v2.33
        https://marc.info/?l=linux-fsdevel&m=154150400305928&w=2
    
    Closes #23 - GParted doesn't detect APFS (Apple File System)

 include/Utils.h     | 21 +++++++++++----------
 src/GParted_Core.cc | 17 ++++++++++++++++-
 src/Utils.cc        |  2 ++
 3 files changed, 29 insertions(+), 11 deletions(-)
---
diff --git a/include/Utils.h b/include/Utils.h
index 20ab1153..ec5b4904 100644
--- a/include/Utils.h
+++ b/include/Utils.h
@@ -92,18 +92,19 @@ enum FSType
        FS_XFS             = 27,
 
        // Other recognised file system types
-       FS_BITLOCKER       = 28,
-       FS_GRUB2_CORE_IMG  = 29,
-       FS_ISO9660         = 30,
-       FS_LINUX_SWRAID    = 31,
-       FS_LINUX_SWSUSPEND = 32,
-       FS_REFS            = 33,
-       FS_UFS             = 34,
-       FS_ZFS             = 35,
+       FS_APFS            = 28,
+       FS_BITLOCKER       = 29,
+       FS_GRUB2_CORE_IMG  = 30,
+       FS_ISO9660         = 31,
+       FS_LINUX_SWRAID    = 32,
+       FS_LINUX_SWSUSPEND = 33,
+       FS_REFS            = 34,
+       FS_UFS             = 35,
+       FS_ZFS             = 36,
 
        // Partition space usage colours
-       FS_USED            = 36,
-       FS_UNUSED          = 37
+       FS_USED            = 37,
+       FS_UNUSED          = 38
 } ;
 
 enum SIZE_UNIT
diff --git a/src/GParted_Core.cc b/src/GParted_Core.cc
index 88036405..fa4abbd6 100644
--- a/src/GParted_Core.cc
+++ b/src/GParted_Core.cc
@@ -1332,7 +1332,8 @@ FSType GParted_Core::detect_filesystem_internal( PedDevice * lp_device, PedParti
                {     0LL, "\x52\xE8\x28\x01",     0LL, NULL  , FS_GRUB2_CORE_IMG },
                {     0LL, "\x52\xBF\xF4\x81",     0LL, NULL  , FS_GRUB2_CORE_IMG },
                {     0LL, "\x52\x56\xBE\x63",     0LL, NULL  , FS_GRUB2_CORE_IMG },
-               {     0LL, "\x52\x56\xBE\x56",     0LL, NULL  , FS_GRUB2_CORE_IMG }
+               {     0LL, "\x52\x56\xBE\x56",     0LL, NULL  , FS_GRUB2_CORE_IMG },
+               {    24LL, "\x01\x00"        ,    32LL, "NXSB", FS_APFS           }
        };
        // For simple BitLocker recognition consider validation of BIOS Parameter block
        // fields unnecessary.
@@ -1343,6 +1344,17 @@ FSType GParted_Core::detect_filesystem_internal( PedDevice * lp_device, PedParti
        // instructions it starts with.
        // *   bootinfoscript v0.77 line 1990  [GRUB2 core.img possible staring 4 bytes]
        //     
https://github.com/arvidjaar/bootinfoscript/blob/009f509d59e2f0d39b8d44692e2a81720f5af7b6/bootinfoscript#L1990
+       //
+       // Simple APFS recognition based on matching the following fields in the
+       // superblock:
+       // 1)  Object type is OBJECT_TYPE_NX_SUPERBLOCK, lower 16-bits of the object type
+       //     field is 0x0001 stored as little endian bytes 0x01, 0x00.
+       //     WARNING: The magic signatures are defined as NUL terminated strings so the
+       //     below code only does a 1-byte match for 0x01, rather than a 2-byte match
+       //     for 0x01, 0x00.
+       // 2)  4 byte magic "NXSB".
+       // *   Apple File System Reference
+       //     https://developer.apple.com/support/apple-file-system/Apple-File-System-Reference.pdf
 
        for ( unsigned int i = 0 ; i < sizeof( signatures ) / sizeof( signatures[0] ) ; i ++ )
        {
@@ -1473,6 +1485,8 @@ FSType GParted_Core::detect_filesystem( PedDevice * lp_device, PedPartition * lp
                        return GParted::FS_UDF;
                else if ( fsname == "ufs" )
                        return GParted::FS_UFS ;
+               else if ( fsname == "apfs" )
+                       return FS_APFS;
                else if ( fsname == "BitLocker" )
                        return FS_BITLOCKER;
                else if ( fsname == "iso9660" )
@@ -4182,6 +4196,7 @@ void GParted_Core::init_filesystems()
        FILESYSTEM_MAP[FS_REISERFS]        = new reiserfs();
        FILESYSTEM_MAP[FS_UDF]             = new udf();
        FILESYSTEM_MAP[FS_XFS]             = new xfs();
+       FILESYSTEM_MAP[FS_APFS]            = NULL;
        FILESYSTEM_MAP[FS_BITLOCKER]       = NULL;
        FILESYSTEM_MAP[FS_GRUB2_CORE_IMG]  = NULL;
        FILESYSTEM_MAP[FS_ISO9660]         = NULL;
diff --git a/src/Utils.cc b/src/Utils.cc
index 80e5704e..2e55d162 100644
--- a/src/Utils.cc
+++ b/src/Utils.cc
@@ -116,6 +116,7 @@ Glib::ustring Utils::get_color( FSType filesystem )
                case FS_REISERFS:        return "#ADA7C8";  // Purple Hilight
                case FS_UDF:             return "#105210";  // Accent Green Shadow [+]
                case FS_XFS:             return "#EED680";  // Accent Yellow
+               case FS_APFS:            return "#874986";  // Magenta Dark [*]
                case FS_BITLOCKER:       return "#494066";  // Purple Shadow
                case FS_GRUB2_CORE_IMG:  return "#666666";  // Dark Gray [*]
                case FS_ISO9660:         return "#D3D3D3";  // Light Gray [*]
@@ -304,6 +305,7 @@ Glib::ustring Utils::get_filesystem_string( FSType filesystem )
                case FS_REISERFS:        return "reiserfs";
                case FS_UDF:             return "udf";
                case FS_XFS:             return "xfs";
+               case FS_APFS:            return "apfs";
                case FS_BITLOCKER:       return "bitlocker";
                case FS_GRUB2_CORE_IMG:  return "grub2 core.img";
                case FS_ISO9660:         return "iso9660";