localcharset: Move mapping tables into the code. * lib/localcharset.h: Document the GNU canonical names for character encodings here. * lib/localcharset.c: Don't include <fcntl.h>, <unistd.h>, relocatable.h, configmake.h. (O_NOFOLLOW, ISSLASH, DIRECTORY_SEPARATOR, getc, volatile): Remove macros. (charset_aliases): Remove variable. (get_charset_aliases): Remove function. (struct table_entry): New type. (alias_table, locale_table): New constants. (locale_charset): Use the alias_table or locale_table to get the canonicalized encoding name. * lib/config.charset: Remove file. * lib/ref-add.sin: Remove file. * lib/ref-del.sin: Remove file. * m4/localcharset.m4 (gl_LOCALCHARSET): Don't require gl_FCNTL_O_FLAGS, AC_CANONICAL_HOST, gl_GLIBC21. Don't check for getc_unlocked. * modules/localcharset (Notice): Remove. (Files): Remove config.charset, ref-add.sin, ref-del.sin, fcntl-o.m4, glibc21.m4. (Depends-on): Remove configmake. (configure.ac): Define LOCALCHARSET_TESTS_ENVIRONMENT to empty. (Makefile.am): Simplify. * build-aux/prefix-gnulib-mk: Remove special code for the removed files.

# localcharset.m4 serial 8
dnl Copyright (C) 2002, 2004, 2006, 2009-2018 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_LOCALCHARSET],
[
  dnl Prerequisites of lib/localcharset.c.
  AC_REQUIRE([AM_LANGINFO_CODESET])
])