Run "TZ=UTC0 admin/update-copyright".

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".

* src/regex-emacs.c (re_match_2_internal):
No need to allocate one extra trailing search register;
Emacs does not use it.  Avoid quadratic behavior on
reallocation.

Also, remove some duplicate comments related to thread.h.
* src/regex-emacs.h (struct re_registers):
* src/regex-emacs.c (SIGN_EXTEND_CHAR): Remove.
(TALLOC, RETALLOC): Remove.  All uses replaced by usual
allocators, which check for integer overflow.
(extract_number): Redo without using ‘unsigned’.
(CHARSET_RANGE_TABLE_EXISTS_P): Clearly return a boolean.
(print_fastmap, print_partial_compiled_pattern, CHECK_INFINITE_LOOP)
(regex_compile, analyze_first, bcmp_translate, mutually_exclusive_p)
(re_match_2_internal):
Use bool for booleans.
(print_fastmap, regex_compile, execute_charset):
Prefer int to unsigned where either will do.
(print_double_string): Prefer ptrdiff_t to ssize_t, since the
latter can in theory be narrower than the former.  Use fwrite
instead of repeated putchar.
(emacs_re_max_failures, fail_stack_type, compile_stack_type)
(re_wctype_parse, regex_compile, re_search, re_search_2)
(re_match_2, re_match_2_internal, re_compile_pattern):
Prefer ptrdiff_t to size_t where either will do.
(union fail_stack_elt, PUSH_FAILURE_REG, POP_FAILURE_REG_OR_COUNT):
Make the integer an intptr_t, not long.
(GET_BUFFER_SPACE, EXTEND_BUFFER, regex_compile):
Use xpalloc to simplify allocation.
(regex_compile): Check for integer overflow when calculating
register numbers.
* src/regex-emacs.c (re_set_registers, re_match_2_internal):
* src/regex-emacs.h (struct re_registers, struct re_pattern_buffer):
* src/search.c (Freplace_match):
Prefer ptrdiff_t to unsigned where either will do.
* src/regex-emacs.h (struct re_pattern_buffer):
Prefer bool_bf to unsigned where either will do.

Update some other copyright years automatically, by running:
Run 'UPDATE_COPYRIGHT_YEAR=2019 \
UPDATE_COPYRIGHT_USE_INTERVALS=1 \
UPDATE_COPYRIGHT_MAX_LINE_LENGTH=79 admin/update-copyright'
followed by 'admin/merge-gnulib'.

* src/regex-emacs.c, src/regex-emacs.h: Update comments.

* src/regex-emacs.h (struct re_pattern_buffer):
Remove no_sub, not_bol, not_eol.  They are always zero.
All uses removed, and code simplified.

* src/regex-emacs.c: Omit no-longer-needed AIX code.
Don’t ignore GCC warnings.
Include regex-emacs.h immediately after config.h,
to test that it’s independent.
Omit the "#ifndef emacs" and "#ifdef REGEX_MALLOC" and
"#if WIDE_CHAR_SUPPORT" or "#ifdef _REGEX_RE_COMP",
code, as we are no longer interested in compiling outside
Emacs (with or without debugging or native wide char support)
or in avoiding alloca.
(REGEX_EMACS_DEBUG, regex_emacs_debug): Rename from DEBUG and debug,
to avoid collision with other DEBUGS.  All uses changed.
In debugging output, change %ld and %zd to %zu when appropriate.
No need to include stddef.h, stdlib.h, sys/types.h, wchar.h,
wctype.h, locale/localeinfo.h, locale/elem-hash.h, langinfo.h,
libintl.h, unistd.h, stdbool.h, string.h, stdio.h, assert.h.
All uses of assert changed to eassert.
(RE_DUP_MAX, reg_syntax_t, RE_BACKSLASH_ESCAPE_IN_LISTS)
(RE_BK_PLUS_QM, RE_CHAR_CLASSES, RE_CONTEXT_INDEP_ANCHORS)
(RE_CONTEXT_INDEP_OPS, RE_CONTEXT_INVALID_OPS, RE_DOT_NEWLINE)
(RE_DOT_NOT_NULL, RE_HAT_LISTS_NOT_NEWLINE, RE_INTERVALS)
(RE_LIMITED_OPS, RE_NEWLINE_ALT, RE_NO_BK_BRACES)
(RE_NO_BK_PARENS, RE_NO_BK_REFS, RE_NO_BK_VBAR)
(RE_NO_EMPTY_RANGES, RE_UNMATCHED_RIGHT_PAREN_ORD)
(RE_NO_POSIX_BACKTRACKING, RE_NO_GNU_OPS, RE_FRUGAL)
(RE_SHY_GROUPS, RE_NO_NEWLINE_ANCHOR, RE_SYNTAX_EMACS)
(REG_NOERROR, REG_NOMATCH, REG_BADPAT, REG_ECOLLATE)
(REG_ECTYPE, REG_EESCAPE, REG_ESUBREG, REG_EBRACK, REG_EPAREN)
(REG_EBRACE, REG_BADBR, REG_ERANGE, REG_ESPACE, REG_BADRPT)
(REG_EEND, REG_ESIZE, REG_ERPAREN, REG_ERANGEX, REG_ESIZEBR)
(reg_errcode_t, REGS_UNALLOCATED, REGS_REALLOCATE, REGS_FIXED)
(RE_NREGS, RE_TRANSLATE, RE_TRANSLATE_P):
Move here from regex-emacs.h.
(RE_NREGS): Define unconditionally.
(boolean): Remove.  All uses replaced by bool.
(WIDE_CHAR_SUPPORT, regfree, regexec, regcomp, regerror):
(re_set_syntax, re_syntax_options, WEAK_ALIAS, gettext, gettext_noop):
Remove.  All uses removed.
(malloc, realloc, free): Do not redefine.  Adjust all callers
to use xmalloc, xrealloc, xfree instead.
(re_error_msgid): Use C99 to avoid need to keep in same order
as reg_error_t.
(REGEX_USE_SAFE_ALLOCA): Simplify by using USE_SAFE_ALLOCA.
(REGEX_ALLOCATE, REGEX_REALLOCATE, REGEX_FREE, REGEX_ALLOCATE_STACK)
(REGEX_REALLOCATE_STACK, REGEX_FREE_STACK): Remove.
All callers changed to use the non-REGEX_MALLOC version.
(REGEX_TALLOC): Remove.  All callers changed to use SAFE_ALLOCA.
(re_set_syntax): Remove; unused.
(MATCH_MAY_ALLOCATE): Remove; now always true.  All uses simplified.
(INIT_FAILURE_ALLOC): Define unconditionally.
(re_compile_fastmap): Now static.
(re_compile_pattern): Avoid unnecessary cast.
* src/regex-emacs.h (EMACS_REGEX_H): Renamed from _REGEX_H to
avoid possible collision with glibc.
Don’t include sys/types.h.  All uses of ssize_t changed to ptrdiff_t.
Don’t worry about C++ or VMS.
Assume emacs is defined and that _REGEX_RE_COMP and WIDE_CHAR_SUPPORT
are not.
Define struct re_registers before including lisp.h.
(REG_ENOSYS, RE_TRANSLATE_TYPE): Remove; all uses replaced by
Lisp_Object.
(regoff_t): Remove.  All uses replaced with ptrdiff_t.
(re_match, regcomp, regexec, regerror, regfree):
Remove decl of nonexistent functions.
(RE_DEBUG, RE_SYNTAX_AWK, RE_SYNTAX_GNU_AWK)
(RE_SYNTAX_POSIX_AWK, RE_SYNTAX_GREP, RE_SYNTAX_EGREP)
(RE_SYNTAX_POSIX_EGREP, RE_SYNTAX_ED, RE_SYNTAX_SED)
(_RE_SYNTAX_POSIX_COMMON, RE_SYNTAX_POSIX_BASIC)
(RE_SYNTAX_POSIX_MINIMAL_BASIC, RE_SYNTAX_POSIX_EXTENDED)
(RE_SYNTAX_POSIX_MINIMAL_EXTENDED, REG_EXTENDED, REG_ICASE)
(REG_NEWLINE, REG_NOSUB, REG_NOTBOL, REG_NOTEOL, regmatch_t):
Remove; unused.
* src/search.c (Fset_match_data): Simplify range test now that
we know it’s ptrdiff_t.

Emacs regular expressions forked from everyone else long ago.
This makes it official and should allow simplification later.
etags.c now uses the glibc regex API, falling back on a
Gnulib-supplied substitute lib/regex.c if necessary.
Emacs proper now uses its own regular expression module.
Although this patch may look dauntingly large, most of it
was generated automatically by admin/merge-gnulib
and contains an exact copy of the glibc regex source,
and the by-hand changes do not grow the Emacs source code.
* admin/merge-gnulib (GNULIB_MODULES): Add regex.
(AVOIDED_MODULES): Add btowc, langinfo, lock, mbrtowc, mbsinit,
nl_langinfo, wchar, wcrtomb, wctype-h.
* lib-src/Makefile.in (regex-emacs.o): Remove; Gnulib does it now.
(etags_deps, etags_libs): Remove regex-emacs.o.
* lib-src/etags.c: Go back to including regex.h.
(add_regex): Use unsigned char translation array,
since glibc regex requires that.
* lib/Makefile.in (not_emacs_OBJECTS, for_emacs_OBJECTS): New macros.
(libegnu_a_OBJECTS): Use them, to avoid building e-regex.o.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib/regcomp.c, lib/regex.c, lib/regex.h, lib/regex_internal.c:
* lib/regex_internal.h, lib/regexec.c, m4/builtin-expect.m4:
* m4/eealloc.m4, m4/glibc21.m4, m4/mbstate_t.m4, m4/regex.m4:
New files, copied from Gnulib.
* src/regex-emacs.h, src/conf_post.h:
(RE_TRANSLATE_TYPE, RE_TRANSLATE, RE_TRANSLATE_P):
Move from src/conf_post.h to src/regex-emacs.h,
so that they don’t interfere with compiling lib/regex.c.

This is in preparation for using Gnulib regex for etags,
to avoid collisions in include directives.
* src/regex-emacs.c: Rename from src/regex.c.
* src/regex-emacs.h: Rename from src/regex.h.  All uses changed.
* test/src/regex-emacs-tests.el: Rename from test/src/regex-tests.el.