Move DeviceOpener class to a separate file.

It is used by several of the filesystems, so it seems a good idea to
move it to the shared/ directory.

UFS2, BFS, XFS, EXT2 and EXFAT are adjusted.

Change-Id: I493e37a1e7d3ae24251469f82befd985a3c1dbdd
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2489
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

exfat: handle 4-byte UTF-16 surrogate pairs

... in filenames. Replace the existing Unicode conversion functions
with UTF conversion functions from js that he relicensed MIT for us.

Put the UTF conversion functions in a private but shared code location
so that they can be accessed throughout the kernel.

Right now we only provide functions to convert between UTF-8 and UTF-16.
At some point we should also add functions to convert between UTF-8 and
UTF-32 and UTF-16 and UTF-32 but these aren't needed by exfat.

Remove the old Unicode conversion functions from exfat as they assumed
UCS-2 characters and don't work with UTF-16 used by exfat.

Rename most variables with the term length with code unit where code units
are intended. The term length, when used, means length in bytes while code
units represent either a full 2-byte UTF-16 character or half a 4-byte
surrogate pair.

exfat: Set the mountpoint to same as volume name

Fixes #10501

* update copyright headers, attribute to Haiku, Inc. add authors
* volume_name gets filled out by a utility function in Utility.cpp
* update exfat_entry
- rename name_label to just label
- adjust volume_label to have 11 uint16 chars plus 8 uint8 reserved
- add guid partition info
* Added a couple new entry type defines
* fName is 34 bytes long which fits the 11 3-byte UTF-8 chars and a \0

* Implemented a read-only exFAT file system, tested with a 4GB image.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40409 a95241bf-73f2-0310-859d-f6bbb57e9c96

exfat: handle 4-byte UTF-16 surrogate pairs

... in filenames. Replace the existing Unicode conversion functions
with UTF conversion functions from js that he relicensed MIT for us.

Put the UTF conversion functions in a private but shared code location
so that they can be accessed throughout the kernel.

Right now we only provide functions to convert between UTF-8 and UTF-16.
At some point we should also add functions to convert between UTF-8 and
UTF-32 and UTF-16 and UTF-32 but these aren't needed by exfat.

Remove the old Unicode conversion functions from exfat as they assumed
UCS-2 characters and don't work with UTF-16 used by exfat.

Rename most variables with the term length with code unit where code units
are intended. The term length, when used, means length in bytes while code
units represent either a full 2-byte UTF-16 character or half a 4-byte
surrogate pair.

exfat: Set the mountpoint to same as volume name

Fixes #10501

* update copyright headers, attribute to Haiku, Inc. add authors
* volume_name gets filled out by a utility function in Utility.cpp
* update exfat_entry
- rename name_label to just label
- adjust volume_label to have 11 uint16 chars plus 8 uint8 reserved
- add guid partition info
* Added a couple new entry type defines
* fName is 34 bytes long which fits the 11 3-byte UTF-8 chars and a \0

* Implemented a read-only exFAT file system, tested with a 4GB image.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40409 a95241bf-73f2-0310-859d-f6bbb57e9c96