Commit 955405d1 authored by Gabriel Krisman Bertazi's avatar Gabriel Krisman Bertazi Committed by Theodore Ts'o

unicode: introduce UTF-8 character database

The decomposition and casefolding of UTF-8 characters are described in a
prefix tree in utf8data.h, which is a generate from the Unicode
Character Database (UCD), published by the Unicode Consortium, and
should not be edited by hand.  The structures in utf8data.h are meant to
be used for lookup operations by the unicode subsystem, when decoding a
utf-8 string.

mkutf8data.c is the source for a program that generates utf8data.h. It
was written by Olaf Weber from SGI and originally proposed to be merged
into Linux in 2014.  The original proposal performed the compatibility
decomposition, NFKD, but the current version was modified by me to do
canonical decomposition, NFD, as suggested by the community.  The
changes from the original submission are:

  * Rebase to mainline.
  * Fix out-of-tree-build.
  * Update makefile to build 11.0.0 ucd files.
  * drop references to xfs.
  * Convert NFKD to NFD.
  * Merge back robustness fixes from original patch. Requested by
    Dave Chinner.

The original submission is archived at:

<https://linux-xfs.oss.sgi.narkive.com/Xx10wjVY/rfc-unicode-utf-8-support-for-xfs>

The utf8data.h file can be regenerated using the instructions in
fs/unicode/README.utf8data.

- Notes on the update from 8.0.0 to 11.0:

The structure of the ucd files and special cases have not experienced
any changes between versions 8.0.0 and 11.0.0.  8.0.0 saw the addition
of Cherokee LC characters, which is an interesting case for
case-folding.  The update is accompanied by new tests on the test_ucd
module to catch specific cases.  No changes to mkutf8data script were
required for the updates.
Signed-off-by: default avatarGabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 310a997f
......@@ -317,5 +317,6 @@ endif # NETWORK_FILESYSTEMS
source "fs/nls/Kconfig"
source "fs/dlm/Kconfig"
source "fs/unicode/Kconfig"
endmenu
......@@ -92,6 +92,7 @@ obj-$(CONFIG_EXPORTFS) += exportfs/
obj-$(CONFIG_NFSD) += nfsd/
obj-$(CONFIG_LOCKD) += lockd/
obj-$(CONFIG_NLS) += nls/
obj-$(CONFIG_UNICODE) += unicode/
obj-$(CONFIG_SYSV_FS) += sysv/
obj-$(CONFIG_CIFS) += cifs/
obj-$(CONFIG_HPFS_FS) += hpfs/
......
#
# UTF-8 normalization
#
config UNICODE
bool "UTF-8 normalization and casefolding support"
help
Say Y here to enable UTF-8 NFD normalization and NFD+CF casefolding
support.
# SPDX-License-Identifier: GPL-2.0
# This rule is not invoked during the kernel compilation. It is used to
# regenerate the utf8data.h header file.
utf8data.h.new: *.txt $(objdir)/scripts/mkutf8data
$(objdir)/scripts/mkutf8data \
-a DerivedAge.txt \
-c DerivedCombiningClass.txt \
-p DerivedCoreProperties.txt \
-d UnicodeData.txt \
-f CaseFolding.txt \
-n NormalizationCorrections.txt \
-t NormalizationTest.txt \
-o $@
The utf8data.h file in this directory is generated from the Unicode
Character Database for version 11.0.0 of the Unicode standard.
The full set of files can be found here:
http://www.unicode.org/Public/11.0.0/ucd/
Individual source links:
http://www.unicode.org/Public/11.0.0/ucd/CaseFolding.txt
http://www.unicode.org/Public/11.0.0/ucd/DerivedAge.txt
http://www.unicode.org/Public/11.0.0/ucd/extracted/DerivedCombiningClass.txt
http://www.unicode.org/Public/11.0.0/ucd/DerivedCoreProperties.txt
http://www.unicode.org/Public/11.0.0/ucd/NormalizationCorrections.txt
http://www.unicode.org/Public/11.0.0/ucd/NormalizationTest.txt
http://www.unicode.org/Public/11.0.0/ucd/UnicodeData.txt
md5sums (verify by running "md5sum -c README.utf8data"):
414436796cf097df55f798e1585448ee CaseFolding.txt
6032a595fbb782694456491d86eecfac DerivedAge.txt
3240997d671297ac754ab0d27577acf7 DerivedCombiningClass.txt
2a4fe257d9d8184518e036194d2248ec DerivedCoreProperties.txt
4e7d383fa0dd3cd9d49d64e5b7b7c9e0 NormalizationCorrections.txt
c9500c5b8b88e584469f056023ecc3f2 NormalizationTest.txt
acc291106c3758d2025f8d7bd5518bee UnicodeData.txt
sha1sums (verify by running "sha1sum -c README.utf8data"):
9184727adf7bd20e36312a68581d12ba3ffb9854 CaseFolding.txt
86c55b3eb89de61704da16af9c3f22854f61b57d DerivedAge.txt
b615703f62b1dbc5110e91acc3ff8b3789a067cf DerivedCombiningClass.txt
f8b07ef116d7dc21a94f26e70178ed2acf8713e9 DerivedCoreProperties.txt
a5fafb8998c0b8153a2a58430b8a35c811db0abc NormalizationCorrections.txt
070cdcb00cd4f0860e476750e404c59c2ebe9b25 NormalizationTest.txt
0e060fafb08d6722fbec56d9f9ebe8509f01d0ee UnicodeData.txt
To update to the newer version of the Unicode standard, the latest
released version of the UCD can be found here:
http://www.unicode.org/Public/UCD/latest/
To build the utf8data.h file, from a kernel tree that has been built,
cd to this directory (fs/unicode) and run this command:
make C=../.. objdir=../.. utf8data.h.new
After sanity checking the newly generated utf8data.h.new file (the
version generated from the 11.0.0 UCD should be 13,834 lines long, and
have a total size of 1104k) and/or comparing it with the older version
of utf8data.h, rename it to utf8data.h.
If you are a kernel developer updating to a newer version of the
Unicode Character Database, please update this README.utf8data file
with the version of the UCD that was used, the md5sum and sha1sums of
the *.txt files, before checking in the new versions of the utf8data.h
and README.utf8data files.
This diff is collapsed.
......@@ -20,6 +20,7 @@ hostprogs-$(CONFIG_ASN1) += asn1_compiler
hostprogs-$(CONFIG_MODULE_SIG) += sign-file
hostprogs-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += extract-cert
hostprogs-$(CONFIG_SYSTEM_EXTRA_CERTIFICATE) += insert-sys-cert
hostprogs-$(CONFIG_UNICODE) += mkutf8data
HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include
HOSTCFLAGS_asn1_compiler.o = -I$(srctree)/include
......
This diff is collapsed.
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment