maint.mk 47.9 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
# -*-Makefile-*-
# This Makefile fragment tries to be general-purpose enough to be
# used by many projects via the gnulib maintainer-makefile module.

## Copyright (C) 2001-2019 Free Software Foundation, Inc.
##
## This program is free software: you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program.  If not, see <https://www.gnu.org/licenses/>.

# This is reported not to work with make-3.79.1
# ME := $(word $(words $(MAKEFILE_LIST)),$(MAKEFILE_LIST))
22
ME := $(_build-aux)/maint.mk
23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89

# These variables ought to be defined through the configure.ac section
# of the module description. But some packages import this file directly,
# ignoring the module description.
AWK ?= awk
GREP ?= grep
SED ?= sed

# Helper variables.
_empty =
_sp = $(_empty) $(_empty)

# _equal,S1,S2
# ------------
# If S1 == S2, return S1, otherwise the empty string.
_equal = $(and $(findstring $(1),$(2)),$(findstring $(2),$(1)))

GIT = git
VC = $(GIT)

VC_LIST = $(srcdir)/$(_build-aux)/vc-list-files -C $(srcdir)

# You can override this variable in cfg.mk if your gnulib submodule lives
# in a different location.
gnulib_dir ?= $(srcdir)/gnulib

# You can override this variable in cfg.mk to set your own regexp
# matching files to ignore.
VC_LIST_ALWAYS_EXCLUDE_REGEX ?= ^$$

# This is to preprocess robustly the output of $(VC_LIST), so that even
# when $(srcdir) is a pathological name like "....", the leading sed command
# removes only the intended prefix.
_dot_escaped_srcdir = $(subst .,\.,$(srcdir))

# Post-process $(VC_LIST) output, prepending $(srcdir)/, but only
# when $(srcdir) is not ".".
ifeq ($(srcdir),.)
  _prepend_srcdir_prefix =
else
  _prepend_srcdir_prefix = | $(SED) 's|^|$(srcdir)/|'
endif

# In order to be able to consistently filter "."-relative names,
# (i.e., with no $(srcdir) prefix), this definition is careful to
# remove any $(srcdir) prefix, and to restore what it removes.
_sc_excl = \
  $(or $(exclude_file_name_regexp--$@),^$$)
VC_LIST_EXCEPT = \
  $(VC_LIST) | $(SED) 's|^$(_dot_escaped_srcdir)/||' \
	| if test -f $(srcdir)/.x-$@; then $(GREP) -vEf $(srcdir)/.x-$@; \
	  else $(GREP) -Ev -e "$${VC_LIST_EXCEPT_DEFAULT-ChangeLog}"; fi \
	| $(GREP) -Ev -e '($(VC_LIST_ALWAYS_EXCLUDE_REGEX)|$(_sc_excl))' \
	$(_prepend_srcdir_prefix)

# Override this in cfg.mk if you are using a different format in your
# NEWS file.
today = $(shell date +%Y-%m-%d)

# Prevent programs like 'sort' from considering distinct strings to be equal.
# Doing it here saves us from having to set LC_ALL elsewhere in this file.
export LC_ALL = C

## --------------- ##
## Sanity checks.  ##
## --------------- ##

90
_cfg_mk := $(wildcard $(srcdir)/$(_build-aux)/cfg.mk)
91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834

# Collect the names of rules starting with 'sc_'.
syntax-check-rules := $(sort $(shell $(SED) -n \
   's/^\(sc_[a-zA-Z0-9_-]*\):.*/\1/p' $(srcdir)/$(ME) $(_cfg_mk)))
.PHONY: $(syntax-check-rules)

ifeq ($(shell $(VC_LIST) >/dev/null 2>&1; echo $$?),0)
  local-checks-available += $(syntax-check-rules)
else
  local-checks-available += no-vc-detected
no-vc-detected:
	@echo "No version control files detected; skipping syntax check"
endif
.PHONY: $(local-checks-available)

# Arrange to print the name of each syntax-checking rule just before running it.
$(syntax-check-rules): %: %.m
sc_m_rules_ = $(patsubst %, %.m, $(syntax-check-rules))
.PHONY: $(sc_m_rules_)
$(sc_m_rules_):
	@echo $(patsubst sc_%.m, %, $@)
	@date +%s.%N > .sc-start-$(basename $@)

# Compute and print the elapsed time for each syntax-check rule.
sc_z_rules_ = $(patsubst %, %.z, $(syntax-check-rules))
.PHONY: $(sc_z_rules_)
$(sc_z_rules_): %.z: %
	@end=$$(date +%s.%N);						\
	start=$$(cat .sc-start-$*);					\
	rm -f .sc-start-$*;						\
	$(AWK) -v s=$$start -v e=$$end					\
	  'END {printf "%.2f $(patsubst sc_%,%,$*)\n", e - s}' < /dev/null

# The patsubst here is to replace each sc_% rule with its sc_%.z wrapper
# that computes and prints elapsed time.
local-check :=								\
  $(patsubst sc_%, sc_%.z,						\
    $(filter-out $(local-checks-to-skip), $(local-checks-available)))

syntax-check: $(local-check)

# _sc_search_regexp
#
# This macro searches for a given construct in the selected files and
# then takes some action.
#
# Parameters (shell variables):
#
#  prohibit | require
#
#     Regular expression (ERE) denoting either a forbidden construct
#     or a required construct.  Those arguments are exclusive.
#
#  exclude
#
#     Regular expression (ERE) denoting lines to ignore that matched
#     a prohibit construct.  For example, this can be used to exclude
#     comments that mention why the nearby code uses an alternative
#     construct instead of the simpler prohibited construct.
#
#  in_vc_files | in_files
#
#     grep-E-style regexp selecting the files to check.  For in_vc_files,
#     the regexp is used to select matching files from the list of all
#     version-controlled files; for in_files, it's from the names printed
#     by "find $(srcdir)".  When neither is specified, use all files that
#     are under version control.
#
#  containing | non_containing
#
#     Select the files (non) containing strings matching this regexp.
#     If both arguments are specified then CONTAINING takes
#     precedence.
#
#  with_grep_options
#
#     Extra options for grep.
#
#  ignore_case
#
#     Ignore case.
#
#  halt
#
#     Message to display before to halting execution.
#
# Finally, you may exempt files based on an ERE matching file names.
# For example, to exempt from the sc_space_tab check all files with the
# .diff suffix, set this Make variable:
#
# exclude_file_name_regexp--sc_space_tab = \.diff$
#
# Note that while this functionality is mostly inherited via VC_LIST_EXCEPT,
# when filtering by name via in_files, we explicitly filter out matching
# names here as well.

# Initialize each, so that envvar settings cannot interfere.
export require =
export prohibit =
export exclude =
export in_vc_files =
export in_files =
export containing =
export non_containing =
export halt =
export with_grep_options =

# By default, _sc_search_regexp does not ignore case.
export ignore_case =
_ignore_case = $$(test -n "$$ignore_case" && printf %s -i || :)

define _sc_say_and_exit
   dummy=; : so we do not need a semicolon before each use;		\
   { printf '%s\n' "$(ME): $$msg" 1>&2; exit 1; };
endef

define _sc_search_regexp
   dummy=; : so we do not need a semicolon before each use;		\
									\
   : Check arguments;							\
   test -n "$$prohibit" && test -n "$$require"				\
     && { msg='Cannot specify both prohibit and require'		\
          $(_sc_say_and_exit) } || :;					\
   test -z "$$prohibit" && test -z "$$require"				\
     && { msg='Should specify either prohibit or require'		\
          $(_sc_say_and_exit) } || :;					\
   test -z "$$prohibit" && test -n "$$exclude"				\
     && { msg='Use of exclude requires a prohibit pattern'		\
          $(_sc_say_and_exit) } || :;					\
   test -n "$$in_vc_files" && test -n "$$in_files"			\
     && { msg='Cannot specify both in_vc_files and in_files'		\
          $(_sc_say_and_exit) } || :;					\
   test "x$$halt" != x							\
     || { msg='halt not defined' $(_sc_say_and_exit) };			\
									\
   : Filter by file name;						\
   if test -n "$$in_files"; then					\
     files=$$(find $(srcdir) | $(GREP) -E "$$in_files"			\
              | $(GREP) -Ev '$(_sc_excl)');				\
   else									\
     files=$$($(VC_LIST_EXCEPT));					\
     if test -n "$$in_vc_files"; then					\
       files=$$(echo "$$files" | $(GREP) -E "$$in_vc_files");		\
     fi;								\
   fi;									\
									\
   : Filter by content;							\
   test -n "$$files"							\
     && test -n "$$containing"						\
     && { files=$$(echo "$$files" | xargs $(GREP) -l "$$containing"); }	\
     || :;								\
   test -n "$$files"							\
     && test -n "$$non_containing"					\
     && { files=$$(echo "$$files" | xargs $(GREP) -vl "$$non_containing"); } \
     || :;								\
									\
   : Check for the construct;						\
   if test -n "$$files"; then						\
     if test -n "$$prohibit"; then					\
       echo "$$files"							\
         | xargs $(GREP) $$with_grep_options $(_ignore_case) -nE	\
		"$$prohibit" /dev/null					\
         | $(GREP) -vE "$${exclude:-^$$}"				\
         && { msg="$$halt" $(_sc_say_and_exit) }			\
         || :;								\
     else								\
       echo "$$files"							\
         | xargs							\
             $(GREP) $$with_grep_options $(_ignore_case) -LE "$$require" \
         | $(GREP) .							\
         && { msg="$$halt" $(_sc_say_and_exit) }			\
         || :;								\
     fi									\
   else :;								\
   fi || :;
endef

sc_avoid_if_before_free:
	@$(VC_LIST_EXCEPT)						\
	  | $(GREP) -v useless-if-before-free				\
	  | xargs							\
	      $(srcdir)/$(_build-aux)/useless-if-before-free		\
	      $(useless_free_options)					\
	  && { printf '$(ME): found useless "if"'			\
		      ' before "free" above\n' 1>&2;			\
	       exit 1; }						\
	  || :

sc_cast_of_argument_to_free:
	@prohibit='\<free *\( *\(' halt="don't cast free argument"	\
	  $(_sc_search_regexp)

sc_cast_of_x_alloc_return_value:
	@prohibit='\*\) *x(m|c|re)alloc\>'				\
	halt="don't cast x*alloc return value"				\
	  $(_sc_search_regexp)

sc_cast_of_alloca_return_value:
	@prohibit='\*\) *alloca\>'					\
	halt="don't cast alloca return value"				\
	  $(_sc_search_regexp)

sc_space_tab:
	@prohibit='[ ]	'						\
	halt='found SPACE-TAB sequence; remove the SPACE'		\
	  $(_sc_search_regexp)

# Don't use *scanf or the old ato* functions in "real" code.
# They provide no error checking mechanism.
# Instead, use strto* functions.
sc_prohibit_atoi_atof:
	@prohibit='\<([fs]?scanf|ato([filq]|ll)) *\('				\
	halt='do not use *scan''f, ato''f, ato''i, ato''l, ato''ll or ato''q'	\
	  $(_sc_search_regexp)

# Use STREQ rather than comparing strcmp == 0, or != 0.
sp_ = strcmp *\(.+\)
sc_prohibit_strcmp:
	@prohibit='! *strcmp *\(|\<$(sp_) *[!=]=|[!=]= *$(sp_)'		\
	exclude='# *define STRN?EQ\('					\
	halt='replace strcmp calls above with STREQ/STRNEQ'		\
	  $(_sc_search_regexp)

# Really.  You don't want to use this function.
# It may fail to NUL-terminate the destination,
# and always NUL-pads out to the specified length.
sc_prohibit_strncpy:
	@prohibit='\<strncpy *\('					\
	halt='do not use strncpy, period'				\
	  $(_sc_search_regexp)

# Pass EXIT_*, not number, to usage, exit, and error (when exiting)
# Convert all uses automatically, via these two commands:
# git grep -l '\<exit *(1)' \
#  | grep -vEf .x-sc_prohibit_magic_number_exit \
#  | xargs --no-run-if-empty \
#      perl -pi -e 's/(^|[^.])\b(exit ?)\(1\)/$1$2(EXIT_FAILURE)/'
# git grep -l '\<exit *(0)' \
#  | grep -vEf .x-sc_prohibit_magic_number_exit \
#  | xargs --no-run-if-empty \
#      perl -pi -e 's/(^|[^.])\b(exit ?)\(0\)/$1$2(EXIT_SUCCESS)/'
sc_prohibit_magic_number_exit:
	@prohibit='(^|[^.])\<(usage|exit|error) ?\(-?[0-9]+[,)]'	\
	exclude='exit \(77\)|error ?\(((0|77),|[^,]*)'			\
	halt='use EXIT_* values rather than magic number'		\
	  $(_sc_search_regexp)

# Check that we don't use $< in non-implicit Makefile rules.
#
# To find the Makefiles, trace AC_CONFIG_FILES.  Using VC_LIST would
# miss the Makefiles that are not under VC control (e.g., symlinks
# installed for gettext).  "Parsing" (recursive) uses of SUBDIRS seems
# too delicate.
#
# Use GNU Make's --print-data-base to normalize the rules into some
# easy to parse format: they are separated by two \n.  Look for the
# "section" about non-pattern rules (marked with "# Files") inside
# which there are still the POSIX Make like implicit rules (".c.o").
sc_prohibit_gnu_make_extensions_awk_ =					\
  BEGIN {								\
      RS = "\n\n";							\
      in_rules = 0;							\
  }									\
  /^\# Files/ {								\
      in_rules = 1;							\
  }									\
  /\$$</ && in_rules && $$0 !~ /^(.*\n)*\.\w+(\.\w+)?:/ {		\
      print "Error: " file ": $$< in a non implicit rule\n" $$0;	\
      status = 1;							\
  }									\
  END {									\
     exit status;							\
  }
sc_prohibit_gnu_make_extensions:
	@if $(AWK) --version | grep GNU >/dev/null 2>&1; then		\
	  (cd $(srcdir) && autoconf --trace AC_CONFIG_FILES:'$$1') |	\
	    tr ' ' '\n' |						\
	    $(SED) -ne '/Makefile/{s/\.in$$//;p;}' |			\
	    while read m; do						\
	      $(MAKE) -qp -f $$m .DUMMY-TARGET 2>/dev/null |		\
	        $(AWK) -v file=$$m -e '$($@_awk_)' || exit 1;		\
	    done;							\
	fi

# Using EXIT_SUCCESS as the first argument to error is misleading,
# since when that parameter is 0, error does not exit.  Use '0' instead.
sc_error_exit_success:
	@prohibit='error *\(EXIT_SUCCESS,'				\
	in_vc_files='\.[chly]$$'					\
	halt='found error (EXIT_SUCCESS'				\
	 $(_sc_search_regexp)

# "FATAL:" should be fully upper-cased in error messages
# "WARNING:" should be fully upper-cased, or fully lower-cased
sc_error_message_warn_fatal:
	@$(VC_LIST_EXCEPT)						\
	  | xargs $(GREP) -nEA2 '[^rp]error *\(' /dev/null		\
	  | $(GREP) -E '"Warning|"Fatal|"fatal'				\
	  && { echo '$(ME): use FATAL, WARNING or warning' 1>&2;	\
	       exit 1; }						\
	  || :

# Error messages should not start with a capital letter
sc_error_message_uppercase:
	@$(VC_LIST_EXCEPT)						\
	  | xargs $(GREP) -nEA2 '[^rp]error *\(' /dev/null		\
	  | $(GREP) -E '"[A-Z]'						\
	  | $(GREP) -vE '"FATAL|"WARNING|"Java|"C#|PRIuMAX'		\
	  && { echo '$(ME): found capitalized error message' 1>&2;	\
	       exit 1; }						\
	  || :

# Error messages should not end with a period
sc_error_message_period:
	@$(VC_LIST_EXCEPT)						\
	  | xargs $(GREP) -nEA2 '[^rp]error *\(' /dev/null		\
	  | $(GREP) -E '[^."]\."'					\
	  && { echo '$(ME): found error message ending in period' 1>&2;	\
	       exit 1; }						\
	  || :

sc_file_system:
	@prohibit=file''system						\
	exclude='/proc/filesystems'					\
	ignore_case=1							\
	halt='found use of "file''system"; spell it "file system"'	\
	  $(_sc_search_regexp)

# Don't use cpp tests of this symbol.  All code assumes config.h is included.
sc_prohibit_have_config_h:
	@prohibit='^# *if.*HAVE''_CONFIG_H'				\
	halt='found use of HAVE''_CONFIG_H; remove'			\
	  $(_sc_search_regexp)

# Nearly all .c files must include <config.h>.  However, we also permit this
# via inclusion of a package-specific header, if cfg.mk specified one.
# config_h_header must be suitable for grep -E.
config_h_header ?= <config\.h>
sc_require_config_h:
	@require='^# *include $(config_h_header)'			\
	in_vc_files='\.c$$'						\
	halt='the above files do not include <config.h>'		\
	  $(_sc_search_regexp)

# Print each file name for which the first #include does not match
# $(config_h_header).  Like grep -m 1, this only looks at the first match.
perl_config_h_first_ =							\
  -e 'BEGIN {$$ret = 0}'						\
  -e 'if (/^\# *include\b/) {'						\
  -e '  if (not m{^\# *include $(config_h_header)}) {'			\
  -e '    print "$$ARGV\n";'						\
  -e '    $$ret = 1;'							\
  -e '  }'								\
  -e '  \# Move on to next file after first include'			\
  -e '  close ARGV;'							\
  -e '}'								\
  -e 'END {exit $$ret}'

# You must include <config.h> before including any other header file.
# This can possibly be via a package-specific header, if given by cfg.mk.
sc_require_config_h_first:
	@if $(VC_LIST_EXCEPT) | $(GREP) '\.c$$' > /dev/null; then	\
	  files=$$($(VC_LIST_EXCEPT) | $(GREP) '\.c$$') &&		\
	  perl -n $(perl_config_h_first_) $$files ||			\
	    { echo '$(ME): the above files include some other header'	\
		'before <config.h>' 1>&2; exit 1; } || :;		\
	else :;								\
	fi

sc_prohibit_HAVE_MBRTOWC:
	@prohibit='\bHAVE_MBRTOWC\b'					\
	halt="do not use $$prohibit; it is always defined"		\
	  $(_sc_search_regexp)

# To use this "command" macro, you must first define two shell variables:
# h: the header name, with no enclosing <> or ""
# re: a regular expression that matches IFF something provided by $h is used.
define _sc_header_without_use
  dummy=; : so we do not need a semicolon before each use;		\
  h_esc=`echo '[<"]'"$$h"'[">]'|$(SED) 's/\./\\\\./g'`;			\
  if $(VC_LIST_EXCEPT) | $(GREP) '\.c$$' > /dev/null; then		\
    files=$$($(GREP) -l '^# *include '"$$h_esc"				\
	     $$($(VC_LIST_EXCEPT) | $(GREP) '\.c$$')) &&		\
    $(GREP) -LE "$$re" $$files | $(GREP) . &&				\
      { echo "$(ME): the above files include $$h but don't use it"	\
	1>&2; exit 1; } || :;						\
  else :;								\
  fi
endef

# Prohibit the inclusion of assert.h without an actual use of assert.
sc_prohibit_assert_without_use:
	@h='assert.h' re='\<assert *\(' $(_sc_header_without_use)

# Prohibit the inclusion of close-stream.h without an actual use.
sc_prohibit_close_stream_without_use:
	@h='close-stream.h' re='\<close_stream *\(' $(_sc_header_without_use)

# Prohibit the inclusion of getopt.h without an actual use.
sc_prohibit_getopt_without_use:
	@h='getopt.h' re='\<getopt(_long)? *\(' $(_sc_header_without_use)

# Don't include quotearg.h unless you use one of its functions.
sc_prohibit_quotearg_without_use:
	@h='quotearg.h' re='\<quotearg(_[^ ]+)? *\(' $(_sc_header_without_use)

# Don't include quote.h unless you use one of its functions.
sc_prohibit_quote_without_use:
	@h='quote.h' re='\<quote((_n)? *\(|_quoting_options\>)' \
	  $(_sc_header_without_use)

# Don't include this header unless you use one of its functions.
sc_prohibit_long_options_without_use:
	@h='long-options.h' re='\<parse_(long_options|gnu_standard_options_only) *\(' \
	  $(_sc_header_without_use)

# Don't include this header unless you use one of its functions.
sc_prohibit_inttostr_without_use:
	@h='inttostr.h' re='\<(off|[iu]max|uint)tostr *\(' \
	  $(_sc_header_without_use)

# Don't include this header unless you use one of its functions.
sc_prohibit_ignore_value_without_use:
	@h='ignore-value.h' re='\<ignore_(value|ptr) *\(' \
	  $(_sc_header_without_use)

# Don't include this header unless you use one of its functions.
sc_prohibit_error_without_use:
	@h='error.h' \
	re='\<error(_at_line|_print_progname|_one_per_line|_message_count)? *\('\
	  $(_sc_header_without_use)

# Don't include xalloc.h unless you use one of its functions.
# Consider these symbols:
# perl -lne '/^# *define (\w+)\(/ and print $1' lib/xalloc.h|grep -v '^__';
# perl -lne '/^(?:extern )?(?:void|char) \*?(\w+) *\(/ and print $1' lib/xalloc.h
# Divide into two sets on case, and filter each through this:
# | sort | perl -MRegexp::Assemble -le \
#  'print Regexp::Assemble->new(file => "/dev/stdin")->as_string'|sed 's/\?://g'
# Note this was produced by the above:
# _xa1 = \
#x(((2n?)?re|c(har)?|n(re|m)|z)alloc|alloc_(oversized|die)|m(alloc|emdup)|strdup)
# But we can do better, in at least two ways:
# 1) take advantage of two "dup"-suffixed strings:
# x(((2n?)?re|c(har)?|n(re|m)|[mz])alloc|alloc_(oversized|die)|(mem|str)dup)
# 2) notice that "c(har)?|[mz]" is equivalent to the shorter and more readable
# "char|[cmz]"
# x(((2n?)?re|char|n(re|m)|[cmz])alloc|alloc_(oversized|die)|(mem|str)dup)
_xa1 = x(((2n?)?re|char|n(re|m)|[cmz])alloc|alloc_(oversized|die)|(mem|str)dup)
_xa2 = X([CZ]|N?M)ALLOC
sc_prohibit_xalloc_without_use:
	@h='xalloc.h' \
	re='\<($(_xa1)|$(_xa2)) *\('\
	  $(_sc_header_without_use)

# Extract function names:
# perl -lne '/^(?:extern )?(?:void|char) \*?(\w+) *\(/ and print $1' lib/hash.h
_hash_re = \
clear|delete|free|get_(first|next)|insert|lookup|print_statistics|reset_tuning
_hash_fn = \<($(_hash_re)) *\(
_hash_struct = (struct )?\<[Hh]ash_(table|tuning)\>
sc_prohibit_hash_without_use:
	@h='hash.h' \
	re='$(_hash_fn)|$(_hash_struct)'\
	  $(_sc_header_without_use)

sc_prohibit_cloexec_without_use:
	@h='cloexec.h' re='\<(set_cloexec_flag|dup_cloexec) *\(' \
	  $(_sc_header_without_use)

sc_prohibit_posixver_without_use:
	@h='posixver.h' re='\<posix2_version *\(' $(_sc_header_without_use)

sc_prohibit_same_without_use:
	@h='same.h' re='\<same_name(at)? *\(' $(_sc_header_without_use)

sc_prohibit_hash_pjw_without_use:
	@h='hash-pjw.h' \
	re='\<hash_pjw\>' \
	  $(_sc_header_without_use)

sc_prohibit_safe_read_without_use:
	@h='safe-read.h' re='(\<SAFE_READ_ERROR\>|\<safe_read *\()' \
	  $(_sc_header_without_use)

sc_prohibit_argmatch_without_use:
	@h='argmatch.h' \
	re='(\<(ARRAY_CARDINALITY|X?ARGMATCH(|_TO_ARGUMENT|_VERIFY))\>|\<(invalid_arg|argmatch(_exit_fn|_(in)?valid)?) *\()' \
	  $(_sc_header_without_use)

sc_prohibit_canonicalize_without_use:
	@h='canonicalize.h' \
	re='CAN_(EXISTING|ALL_BUT_LAST|MISSING)|canonicalize_(mode_t|filename_mode|file_name)' \
	  $(_sc_header_without_use)

sc_prohibit_root_dev_ino_without_use:
	@h='root-dev-ino.h' \
	re='(\<ROOT_DEV_INO_(CHECK|WARN)\>|\<get_root_dev_ino *\()' \
	  $(_sc_header_without_use)

sc_prohibit_openat_without_use:
	@h='openat.h' \
	re='\<(openat_(permissive|needs_fchdir|(save|restore)_fail)|l?(stat|ch(own|mod))at|(euid)?accessat|(FCHMOD|FCHOWN|STAT)AT_INLINE)\>' \
	  $(_sc_header_without_use)

# Prohibit the inclusion of c-ctype.h without an actual use.
ctype_re = isalnum|isalpha|isascii|isblank|iscntrl|isdigit|isgraph|islower\
|isprint|ispunct|isspace|isupper|isxdigit|tolower|toupper
sc_prohibit_c_ctype_without_use:
	@h='c-ctype.h' re='\<c_($(ctype_re)) *\(' \
	  $(_sc_header_without_use)

# The following list was generated by running:
# man signal.h|col -b|perl -ne '/bsd_signal.*;/.../sigwaitinfo.*;/ and print' \
#   | perl -lne '/^\s+(?:int|void).*?(\w+).*/ and print $1' | fmt
_sig_functions = \
  bsd_signal kill killpg pthread_kill pthread_sigmask raise sigaction \
  sigaddset sigaltstack sigdelset sigemptyset sigfillset sighold sigignore \
  siginterrupt sigismember signal sigpause sigpending sigprocmask sigqueue \
  sigrelse sigset sigsuspend sigtimedwait sigwait sigwaitinfo
_sig_function_re = $(subst $(_sp),|,$(strip $(_sig_functions)))
# The following were extracted from "man signal.h" manually.
_sig_types_and_consts =							\
  MINSIGSTKSZ SA_NOCLDSTOP SA_NOCLDWAIT SA_NODEFER SA_ONSTACK		\
  SA_RESETHAND SA_RESTART SA_SIGINFO SIGEV_NONE SIGEV_SIGNAL		\
  SIGEV_THREAD SIGSTKSZ SIG_BLOCK SIG_SETMASK SIG_UNBLOCK SS_DISABLE	\
  SS_ONSTACK mcontext_t pid_t sig_atomic_t sigevent siginfo_t sigset_t	\
  sigstack sigval stack_t ucontext_t
# generated via this:
# perl -lne '/^#ifdef (SIG\w+)/ and print $1' lib/sig2str.c|sort -u|fmt -70
_sig_names =								\
  SIGABRT SIGALRM SIGALRM1 SIGBUS SIGCANCEL SIGCHLD SIGCLD SIGCONT	\
  SIGDANGER SIGDIL SIGEMT SIGFPE SIGFREEZE SIGGRANT SIGHUP SIGILL	\
  SIGINFO SIGINT SIGIO SIGIOT SIGKAP SIGKILL SIGKILLTHR SIGLOST SIGLWP	\
  SIGMIGRATE SIGMSG SIGPHONE SIGPIPE SIGPOLL SIGPRE SIGPROF SIGPWR	\
  SIGQUIT SIGRETRACT SIGSAK SIGSEGV SIGSOUND SIGSTKFLT SIGSTOP SIGSYS	\
  SIGTERM SIGTHAW SIGTRAP SIGTSTP SIGTTIN SIGTTOU SIGURG SIGUSR1	\
  SIGUSR2 SIGVIRT SIGVTALRM SIGWAITING SIGWINCH SIGWIND SIGWINDOW	\
  SIGXCPU SIGXFSZ
_sig_syms_re = $(subst $(_sp),|,$(strip $(_sig_names) $(_sig_types_and_consts)))

# Prohibit the inclusion of signal.h without an actual use.
sc_prohibit_signal_without_use:
	@h='signal.h'							\
	re='\<($(_sig_function_re)) *\(|\<($(_sig_syms_re))\>'		\
	  $(_sc_header_without_use)

# Don't include stdio--.h unless you use one of its functions.
sc_prohibit_stdio--_without_use:
	@h='stdio--.h' re='\<((f(re)?|p)open|tmpfile) *\('		\
	  $(_sc_header_without_use)

# Don't include stdio-safer.h unless you use one of its functions.
sc_prohibit_stdio-safer_without_use:
	@h='stdio-safer.h' re='\<((f(re)?|p)open|tmpfile)_safer *\('	\
	  $(_sc_header_without_use)

# Prohibit the inclusion of strings.h without a sensible use.
# Using the likes of bcmp, bcopy, bzero, index or rindex is not sensible.
sc_prohibit_strings_without_use:
	@h='strings.h'							\
	re='\<(strn?casecmp|ffs(ll)?)\>'				\
	  $(_sc_header_without_use)

# Extract the raw list of symbol names with this:
gl_extract_define_simple = \
  /^\# *define ([A-Z]\w+)\(/ and print $$1
# Filter out duplicates and convert to a space-separated list:
_intprops_names = \
  $(shell f=$(gnulib_dir)/lib/intprops.h;				\
    perl -lne '$(gl_extract_define_simple)' $$f | sort -u | tr '\n' ' ')
# Remove trailing space and convert to a regular expression:
_intprops_syms_re = $(subst $(_sp),|,$(strip $(_intprops_names)))
# Prohibit the inclusion of intprops.h without an actual use.
sc_prohibit_intprops_without_use:
	@h='intprops.h'							\
	re='\<($(_intprops_syms_re)) *\('				\
	  $(_sc_header_without_use)

_stddef_syms_re = NULL|offsetof|ptrdiff_t|size_t|wchar_t
# Prohibit the inclusion of stddef.h without an actual use.
sc_prohibit_stddef_without_use:
	@h='stddef.h'							\
	re='\<($(_stddef_syms_re))\>'					\
	  $(_sc_header_without_use)

_de1 = dirfd|(close|(fd)?open|read|rewind|seek|tell)dir(64)?(_r)?
_de2 = (versionsort|struct dirent|getdirentries|alphasort|scandir(at)?)(64)?
_de3 = MAXNAMLEN|DIR|ino_t|d_ino|d_fileno|d_namlen
_dirent_syms_re = $(_de1)|$(_de2)|$(_de3)
# Prohibit the inclusion of dirent.h without an actual use.
sc_prohibit_dirent_without_use:
	@h='dirent.h'							\
	re='\<($(_dirent_syms_re))\>'					\
	  $(_sc_header_without_use)

# Prohibit the inclusion of verify.h without an actual use.
sc_prohibit_verify_without_use:
	@h='verify.h'							\
	re='\<(verify(true|expr)?|assume|static_assert) *\('		\
	  $(_sc_header_without_use)

# Don't include xfreopen.h unless you use one of its functions.
sc_prohibit_xfreopen_without_use:
	@h='xfreopen.h' re='\<xfreopen *\(' $(_sc_header_without_use)

sc_obsolete_symbols:
	@prohibit='\<(HAVE''_FCNTL_H|O''_NDELAY)\>'			\
	halt='do not use HAVE''_FCNTL_H or O'_NDELAY			\
	  $(_sc_search_regexp)

# FIXME: warn about definitions of EXIT_FAILURE, EXIT_SUCCESS, STREQ

# Each nonempty ChangeLog line must start with a year number, or a TAB.
sc_changelog:
	@prohibit='^[^12	]'					\
	in_vc_files='^ChangeLog$$'					\
	halt='found unexpected prefix in a ChangeLog'			\
	  $(_sc_search_regexp)

# Ensure that each .c file containing a "main" function also
# calls bindtextdomain.
sc_bindtextdomain:
	@require='bindtextdomain *\('					\
	in_vc_files='\.c$$'						\
	containing='\<main *('						\
	halt='the above files do not call bindtextdomain'		\
	  $(_sc_search_regexp)

# Require that the final line of each test-lib.sh-using test be this one:
# Exit $fail
# Note: this test requires GNU grep's --label= option.
Exit_witness_file ?= tests/test-lib.sh
Exit_base := $(notdir $(Exit_witness_file))
sc_require_test_exit_idiom:
	@if test -f $(srcdir)/$(Exit_witness_file); then		\
	  die=0;							\
	  for i in $$($(GREP) -l -F 'srcdir/$(Exit_base)'		\
		$$($(VC_LIST) tests)); do				\
	    tail -n1 $$i | $(GREP) '^Exit .' > /dev/null		\
	      && : || { die=1; echo $$i; }				\
	  done;								\
	  test $$die = 1 &&						\
	    { echo 1>&2 '$(ME): the final line in each of the above is not:'; \
	      echo 1>&2 'Exit something';				\
	      exit 1; } || :;						\
	fi

sc_trailing_blank:
	@prohibit='[	 ]$$'						\
	halt='found trailing blank(s)'					\
	exclude='^Binary file .* matches$$'				\
	  $(_sc_search_regexp)

# Match lines like the following, but where there is only one space
# between the options and the description:
#   -D, --all-repeated[=delimit-method]  print all duplicate lines\n
longopt_re = --[a-z][0-9A-Za-z-]*(\[?=[0-9A-Za-z-]*\]?)?
sc_two_space_separator_in_usage:
	@prohibit='^   *(-[A-Za-z],)? $(longopt_re) [^ ].*\\$$'		\
	halt='help2man requires at least two spaces between an option and its description'\
	  $(_sc_search_regexp)

# A regexp matching function names like "error" that may be used
# to emit translatable messages.
_gl_translatable_diag_func_re ?= error

# Look for diagnostics that aren't marked for translation.
# This won't find any for which error's format string is on a separate line.
sc_unmarked_diagnostics:
	@prohibit='\<$(_gl_translatable_diag_func_re) *\([^"]*"[^"]*[a-z]{3}' \
	exclude='(_|ngettext ?)\('					\
	halt='found unmarked diagnostic(s)'				\
	  $(_sc_search_regexp)

# Avoid useless parentheses like those in this example:
# #if defined (SYMBOL) || defined (SYM2)
sc_useless_cpp_parens:
	@prohibit='^# *if .*defined *\('				\
	halt='found useless parentheses in cpp directive'		\
	  $(_sc_search_regexp)

# List headers for which HAVE_HEADER_H is always true, assuming you are
# using the appropriate gnulib module.  CAUTION: for each "unnecessary"
# #if HAVE_HEADER_H that you remove, be sure that your project explicitly
# requires the gnulib module that guarantees the usability of that header.
gl_assured_headers_ = \
  cd $(gnulib_dir)/lib && echo *.in.h|$(SED) 's/\.in\.h//g'

# Convert the list of names to upper case, and replace each space with "|".
az_ = abcdefghijklmnopqrstuvwxyz
AZ_ = ABCDEFGHIJKLMNOPQRSTUVWXYZ
gl_header_upper_case_or_ =						\
  $$($(gl_assured_headers_)						\
    | tr $(az_)/.- $(AZ_)___						\
    | tr -s ' ' '|'							\
    )
sc_prohibit_always_true_header_tests:
	@or=$(gl_header_upper_case_or_);				\
	re="HAVE_($$or)_H";						\
	prohibit='\<'"$$re"'\>'						\
	halt=$$(printf '%s\n'						\
	'do not test the above HAVE_<header>_H symbol(s);'		\
	'  with the corresponding gnulib module, they are always true')	\
	  $(_sc_search_regexp)

sc_prohibit_defined_have_decl_tests:
	@prohibit='(#[	 ]*ifn?def|\<defined)\>[	 (]+HAVE_DECL_'	\
	halt='HAVE_DECL macros are always defined'			\
	  $(_sc_search_regexp)

# ==================================================================
gl_other_headers_ ?= \
  intprops.h	\
  openat.h	\
  stat-macros.h

# Perl -lne code to extract "significant" cpp-defined symbols from a
# gnulib header file, eliminating a few common false-positives.
# The exempted names below are defined only conditionally in gnulib,
# and hence sometimes must/may be defined in application code.
gl_extract_significant_defines_ = \
  /^\# *define ([^_ (][^ (]*)(\s*\(|\s+\w+)/\
    && $$2 !~ /(?:rpl_|_used_without_)/\
    && $$1 !~ /^(?:NSIG|ENODATA)$$/\
    && $$1 !~ /^(?:SA_RESETHAND|SA_RESTART)$$/\
    and print $$1

# Create a list of regular expressions matching the names
# of macros that are guaranteed to be defined by parts of gnulib.
define def_sym_regex
	gen_h=$(gl_generated_headers_);					\
	(cd $(gnulib_dir)/lib;						\
	  for f in *.in.h $(gl_other_headers_); do			\
	    test -f $$f							\
	      && perl -lne '$(gl_extract_significant_defines_)' $$f;	\
	  done;								\
	) | sort -u							\
	  | $(SED) 's/^/^ *# *(define|undef)  */;s/$$/\\>/'
endef

# Don't define macros that we already get from gnulib header files.
sc_prohibit_always-defined_macros:
	@if test -d $(gnulib_dir); then					\
835
	  case $$(echo all: | $(GREP) -l -f - $(abs_top_builddir)/Makefile) in $(abs_top_builddir)/Makefile);; *) \
836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281
	    echo '$(ME): skipping $@: you lack GNU grep' 1>&2; exit 0;;	\
	  esac;								\
	  regex=$$($(def_sym_regex)); export regex;			\
	  $(VC_LIST_EXCEPT)						\
	    | xargs sh -c 'echo $$regex | $(GREP) -E -f - "$$@"'	\
		dummy /dev/null						\
	    && { printf '$(ME): define the above'			\
			' via some gnulib .h file\n' 1>&2;		\
	         exit 1; }						\
	    || :;							\
	fi
# ==================================================================

# Prohibit checked in backup files.
sc_prohibit_backup_files:
	@$(VC_LIST) | $(GREP) '~$$' &&					\
	  { echo '$(ME): found version controlled backup file' 1>&2;	\
	    exit 1; } || :

# Require the latest GPL.
sc_GPL_version:
	@prohibit='either ''version [^3]'				\
	halt='GPL vN, N!=3'						\
	  $(_sc_search_regexp)

# Require the latest GFDL.  Two regexp, since some .texi files end up
# line wrapping between 'Free Documentation License,' and 'Version'.
_GFDL_regexp = (Free ''Documentation.*Version 1\.[^3]|Version 1\.[^3] or any)
sc_GFDL_version:
	@prohibit='$(_GFDL_regexp)'					\
	halt='GFDL vN, N!=3'						\
	  $(_sc_search_regexp)

# Don't use Texinfo's @acronym{}.
# https://lists.gnu.org/r/bug-gnulib/2010-03/msg00321.html
texinfo_suffix_re_ ?= \.(txi|texi(nfo)?)$$
sc_texinfo_acronym:
	@prohibit='@acronym\{'						\
	in_vc_files='$(texinfo_suffix_re_)'				\
	halt='found use of Texinfo @acronym{}'				\
	  $(_sc_search_regexp)

cvs_keywords = \
  Author|Date|Header|Id|Name|Locker|Log|RCSfile|Revision|Source|State

sc_prohibit_cvs_keyword:
	@prohibit='\$$($(cvs_keywords))\$$'				\
	halt='do not use CVS keyword expansion'				\
	  $(_sc_search_regexp)

# This Perl code is slightly obfuscated.  Not only is each "$" doubled
# because it's in a Makefile, but the $$c's are comments;  we cannot
# use "#" due to the way the script ends up concatenated onto one line.
# It would be much more concise, and would produce better output (including
# counts) if written as:
#   perl -ln -0777 -e '/\n(\n+)$/ and print "$ARGV: ".length $1' ...
# but that would be far less efficient, reading the entire contents
# of each file, rather than just the last two bytes of each.
# In addition, while the code below detects both blank lines and a missing
# newline at EOF, the above detects only the former.
#
# This is a perl script that is expected to be the single-quoted argument
# to a command-line "-le".  The remaining arguments are file names.
# Print the name of each file that does not end in exactly one newline byte.
# I.e., warn if there are blank lines (2 or more newlines), or if the
# last byte is not a newline.  However, currently we don't complain
# about any file that contains exactly one byte.
# Exit nonzero if at least one such file is found, otherwise, exit 0.
# Warn about, but otherwise ignore open failure.  Ignore seek/read failure.
#
# Use this if you want to remove trailing empty lines from selected files:
#   perl -pi -0777 -e 's/\n\n+$/\n/' files...
#
require_exactly_one_NL_at_EOF_ =					\
  foreach my $$f (@ARGV)						\
    {									\
      open F, "<", $$f or (warn "failed to open $$f: $$!\n"), next;	\
      my $$p = sysseek (F, -2, 2);					\
      my $$c = "seek failure probably means file has < 2 bytes; ignore"; \
      my $$last_two_bytes;						\
      defined $$p and $$p = sysread F, $$last_two_bytes, 2;		\
      close F;								\
      $$c = "ignore read failure";					\
      $$p && ($$last_two_bytes eq "\n\n"				\
              || substr ($$last_two_bytes,1) ne "\n")			\
          and (print $$f), $$fail=1;					\
    }									\
  END { exit defined $$fail }
sc_prohibit_empty_lines_at_EOF:
	@$(VC_LIST_EXCEPT)						\
	  | xargs perl -le '$(require_exactly_one_NL_at_EOF_)'		\
	  || { echo '$(ME): empty line(s) or no newline at EOF' 1>&2;	\
	       exit 1; }						\
	  || :

# Make sure we don't use st_blocks.  Use ST_NBLOCKS instead.
# This is a bit of a kludge, since it prevents use of the string
# even in comments, but for now it does the job with no false positives.
sc_prohibit_stat_st_blocks:
	@prohibit='[.>]st_blocks'					\
	halt='do not use st_blocks; use ST_NBLOCKS'			\
	  $(_sc_search_regexp)

# Make sure we don't define any S_IS* macros in src/*.c files.
# They're already defined via gnulib's sys/stat.h replacement.
sc_prohibit_S_IS_definition:
	@prohibit='^ *# *define  *S_IS'					\
	halt='do not define S_IS* macros; include <sys/stat.h>'		\
	  $(_sc_search_regexp)

# Perl block to convert a match to FILE_NAME:LINENO:TEST,
# that is shared by two definitions below.
perl_filename_lineno_text_ =						\
    -e '  {'								\
    -e '    $$n = ($$` =~ tr/\n/\n/ + 1);'				\
    -e '    ($$v = $$&) =~ s/\n/\\n/g;'					\
    -e '    print "$$ARGV:$$n:$$v\n";'					\
    -e '  }'

prohibit_doubled_words_ = \
    the then in an on if is it but for or at and do to
# expand the regex before running the check to avoid using expensive captures
prohibit_doubled_word_expanded_ = \
    $(join $(prohibit_doubled_words_),$(addprefix \s+,$(prohibit_doubled_words_)))
prohibit_doubled_word_RE_ ?= \
    /\b(?:$(subst $(_sp),|,$(prohibit_doubled_word_expanded_)))\b/gims
prohibit_doubled_word_ =						\
    -e 'while ($(prohibit_doubled_word_RE_))'				\
    $(perl_filename_lineno_text_)

# Define this to a regular expression that matches
# any filename:dd:match lines you want to ignore.
# The default is to ignore no matches.
ignore_doubled_word_match_RE_ ?= ^$$

sc_prohibit_doubled_word:
	@$(VC_LIST_EXCEPT)						\
	  | xargs perl -n -0777 $(prohibit_doubled_word_)		\
	  | $(GREP) -vE '$(ignore_doubled_word_match_RE_)'		\
	  | $(GREP) .							\
	  && { echo '$(ME): doubled words' 1>&2; exit 1; }		\
	  || :

# A regular expression matching undesirable combinations of words like
# "can not"; this matches them even when the two words appear on different
# lines, but not when there is an intervening delimiter like "#" or "*".
# Similarly undesirable, "See @xref{...}", since an @xref should start
# a sentence.  Explicitly prohibit any prefix of "see" or "also".
# Also prohibit a prefix matching "\w+ +".
# @pxref gets the same see/also treatment and should be parenthesized;
# presume it must *not* start a sentence.
# POSIX spells it "timestamp" rather than "time\s+stamp", so we do, too.
bad_xref_re_ ?= (?:[\w,:;] +|(?:see|also)\s+)\@xref\{
bad_pxref_re_ ?= (?:[.!?]|(?:see|also))\s+\@pxref\{
prohibit_undesirable_word_seq_RE_ ?=					\
  /(?:\bcan\s+not\b|\btime\s+stamps?\b|$(bad_xref_re_)|$(bad_pxref_re_))/gims
prohibit_undesirable_word_seq_ =					\
    -e 'while ($(prohibit_undesirable_word_seq_RE_))'			\
    $(perl_filename_lineno_text_)
# Define this to a regular expression that matches
# any filename:dd:match lines you want to ignore.
# The default is to ignore no matches.
ignore_undesirable_word_sequence_RE_ ?= ^$$

sc_prohibit_undesirable_word_seq:
	@$(VC_LIST_EXCEPT)						\
	  | xargs perl -n -0777 $(prohibit_undesirable_word_seq_)	\
	  | $(GREP) -vE '$(ignore_undesirable_word_sequence_RE_)'	\
	  | $(GREP) .							\
	  && { echo '$(ME): undesirable word sequence' >&2; exit 1; }   \
	  || :

# Except for shell files and for loops, double semicolon is probably a mistake
sc_prohibit_double_semicolon:
	@prohibit='; *;[	{} \]*(/[/*]|$$)'			\
	in_vc_files='\.[chly]$$'					\
	exclude='\bfor *\(.*\)'						\
	halt="Double semicolon detected"				\
	  $(_sc_search_regexp)

_ptm1 = use "test C1 && test C2", not "test C1 -''a C2"
_ptm2 = use "test C1 || test C2", not "test C1 -''o C2"
# Using test's -a and -o operators is not portable.
# We prefer test over [, since the latter is spelled [[ in configure.ac.
sc_prohibit_test_minus_ao:
	@prohibit='(\<test| \[+) .+ -[ao] '				\
	halt='$(_ptm1); $(_ptm2)'					\
	  $(_sc_search_regexp)

# Avoid a test bashism.
sc_prohibit_test_double_equal:
	@prohibit='(\<test| \[+) .+ == '				\
	containing='#! */bin/[a-z]*sh'					\
	halt='use "test x = x", not "test x =''= x"'			\
	  $(_sc_search_regexp)

# Each program that uses proper_name_utf8 must link with one of the
# ICONV libraries.  Otherwise, some ICONV library must appear in LDADD.
# The perl -0777 invocation below extracts the possibly-multi-line
# definition of LDADD from the appropriate Makefile.am and exits 0
# when it contains "ICONV".
sc_proper_name_utf8_requires_ICONV:
	@progs=$$($(VC_LIST_EXCEPT)					\
		    | xargs $(GREP) -l 'proper_name_utf8 ''("');	\
	if test "x$$progs" != x; then					\
	  fail=0;							\
	  for p in $$progs; do						\
	    dir=$$(dirname "$$p");					\
	    perl -0777							\
	      -ne 'exit !(/^LDADD =(.+?[^\\]\n)/ms && $$1 =~ /ICONV/)'	\
	      $$dir/Makefile.am && continue;				\
	    base=$$(basename "$$p" .c);					\
	    $(GREP) "$${base}_LDADD.*ICONV)" $$dir/Makefile.am > /dev/null	\
	      || { fail=1; echo 1>&2 "$(ME): $$p uses proper_name_utf8"; }; \
	  done;								\
	  test $$fail = 1 &&						\
	    { echo 1>&2 '$(ME): the above do not link with any ICONV library'; \
	      exit 1; } || :;						\
	fi

# Warn about "c0nst struct Foo const foo[]",
# but not about "char const *const foo" or "#define const const".
sc_redundant_const:
	@prohibit='\bconst\b[[:space:][:alnum:]]{2,}\bconst\b'		\
	halt='redundant "const" in declarations'			\
	  $(_sc_search_regexp)

sc_const_long_option:
	@prohibit='^ *static.*struct option '				\
	exclude='const struct option|struct option const'		\
	halt='add "const" to the above declarations'			\
	  $(_sc_search_regexp)

NEWS_hash =								\
  $$($(SED) -n '/^\*.* $(PREV_VERSION_REGEXP) ([0-9-]*)/,$$p'		\
       $(srcdir)/NEWS							\
     | perl -0777 -pe							\
	's/^Copyright.+?Free\sSoftware\sFoundation,\sInc\.\n//ms'	\
     | md5sum -								\
     | $(SED) 's/ .*//')

# Ensure that we don't accidentally insert an entry into an old NEWS block.
sc_immutable_NEWS:
	@if test -f $(srcdir)/NEWS; then				\
	  test "$(NEWS_hash)" = '$(old_NEWS_hash)' && : ||		\
	    { echo '$(ME): you have modified old NEWS' 1>&2; exit 1; };	\
	fi

# Update the hash stored above.  Do this after each release and
# for any corrections to old entries.
update-NEWS-hash: NEWS
	perl -pi -e 's/^(old_NEWS_hash[ \t]+:?=[ \t]+).*/$${1}'"$(NEWS_hash)/" \
	  $(srcdir)/cfg.mk

# Ensure that we use only the standard $(VAR) notation,
# not @...@ in Makefile.am, now that we can rely on automake
# to emit a definition for each substituted variable.
# However, there is still one case in which @VAR@ use is not just
# legitimate, but actually required: when augmenting an automake-defined
# variable with a prefix.  For example, gettext uses this:
# MAKEINFO = env LANG= LC_MESSAGES= LC_ALL= LANGUAGE= @MAKEINFO@
# otherwise, makeinfo would put German or French (current locale)
# navigation hints in the otherwise-English documentation.
#
# Allow the package to add exceptions via a hook in cfg.mk;
# for example, @PRAGMA_SYSTEM_HEADER@ can be permitted by
# setting this to ' && !/PRAGMA_SYSTEM_HEADER/'.
_makefile_at_at_check_exceptions ?=
sc_makefile_at_at_check:
	@perl -ne '/\@\w+\@/'						\
          -e ' && !/(\w+)\s+=.*\@\1\@$$/'				\
          -e ''$(_makefile_at_at_check_exceptions)			\
	  -e 'and (print "$$ARGV:$$.: $$_"), $$m=1; END {exit !$$m}'	\
	    $$($(VC_LIST_EXCEPT) | $(GREP) -E '(^|/)(Makefile\.am|[^/]+\.mk)$$') \
	  && { echo '$(ME): use $$(...), not @...@' 1>&2; exit 1; } || :

sc_makefile_TAB_only_indentation:
	@prohibit='^	[ ]{8}'						\
	in_vc_files='akefile|\.mk$$'					\
	halt='found TAB-8-space indentation'				\
	  $(_sc_search_regexp)

sc_m4_quote_check:
	@prohibit='(AC_DEFINE(_UNQUOTED)?|AC_DEFUN)\([^[]'		\
	in_vc_files='(^configure\.ac|\.m4)$$'				\
	halt='quote the first arg to AC_DEF*'				\
	  $(_sc_search_regexp)

fix_po_file_diag = \
'you have changed the set of files with translatable diagnostics;\n\
apply the above patch\n'

# Generate a list of files in which to search for translatable strings.
perl_translatable_files_list_ =						\
  -e 'foreach $$file (@ARGV) {'						\
  -e '	\# Consider only file extensions with one or two letters'	\
  -e '	$$file =~ /\...?$$/ or next;'					\
  -e '	\# Ignore m4 and mk files'					\
  -e '	$$file =~ /\.m[4k]$$/ and next;'				\
  -e '	\# Ignore a .c or .h file with a corresponding .l or .y file'	\
  -e '	$$file =~ /(.+)\.[ch]$$/ && (-e "$${1}.l" || -e "$${1}.y")'	\
  -e '	  and next;'							\
  -e '	\# Skip unreadable files'					\
  -e '	-r $$file or next;'						\
  -e '	print "$$file ";'						\
  -e '}'

# Verify that all source files using _() (more specifically, files that
# match $(_gl_translatable_string_re)) are listed in po/POTFILES.in.
po_file ?= $(srcdir)/po/POTFILES.in
generated_files ?= $(srcdir)/lib/*.[ch]
_gl_translatable_string_re ?= \b(N?_|gettext *)\([^)"]*("|$$)
sc_po_check:
	@if test -f $(po_file); then					\
	  $(GREP) -E -v '^(#|$$)' $(po_file)				\
	    | $(GREP) -v '^src/false\.c$$' | sort > $@-1;		\
	  { $(VC_LIST_EXCEPT); echo $(generated_files); }		\
	    | xargs perl $(perl_translatable_files_list_)		\
	    | xargs $(GREP) -E -l '$(_gl_translatable_string_re)'	\
	    | $(SED) 's|^$(_dot_escaped_srcdir)/||'			\
	    | sort -u > $@-2;						\
	  diff -u -L $(po_file) -L $(po_file) $@-1 $@-2			\
	    || { printf '$(ME): '$(fix_po_file_diag) 1>&2; exit 1; };	\
	  rm -f $@-1 $@-2;						\
	fi

# Sometimes it is useful to change the PATH environment variable
# in Makefiles.  When doing so, it's better not to use the Unix-centric
# path separator of ':', but rather the automake-provided '$(PATH_SEPARATOR)'.
msg = 'Do not use ":" above; use $$(PATH_SEPARATOR) instead'
sc_makefile_path_separator_check:
	@prohibit='PATH[=].*:'						\
	in_vc_files='akefile|\.mk$$'					\
	halt=$(msg)							\
	  $(_sc_search_regexp)

# Check that 'make alpha' will not fail at the end of the process,
# i.e., when pkg-M.N.tar.xz already exists (either in "." or in ../release)
# and is read-only.
writable-files:
	$(AM_V_GEN)if test -d $(release_archive_dir); then		\
	  for file in $(DIST_ARCHIVES); do				\
	    for p in ./ $(release_archive_dir)/; do			\
	      test -e $$p$$file || continue;				\
	      test -w $$p$$file						\
		|| { echo ERROR: $$p$$file is not writable; fail=1; };	\
	    done;							\
	  done;								\
	  test "$$fail" && exit 1 || : ;				\
	else :;								\
	fi

v_etc_file = $(gnulib_dir)/lib/version-etc.c
sample-test = tests/sample-test
texi = doc/$(PACKAGE).texi
# Make sure that the copyright date in $(v_etc_file) is up to date.
# Do the same for the $(sample-test) and the main doc/.texi file.
sc_copyright_check:
	@require='enum { COPYRIGHT_YEAR = '$$(date +%Y)' };'		\
	in_files=$(v_etc_file)						\
	halt='out of date copyright in $(v_etc_file); update it'	\
	  $(_sc_search_regexp)
	@require='# Copyright \(C\) '$$(date +%Y)' Free'		\
	in_vc_files=$(sample-test)					\
	halt='out of date copyright in $(sample-test); update it'	\
	  $(_sc_search_regexp)
	@require='Copyright @copyright\{\} .*'$$(date +%Y)		\
	in_vc_files=$(texi)						\
	halt='out of date copyright in $(texi); update it'		\
	  $(_sc_search_regexp)

# If tests/help-version exists and seems to be new enough, assume that its
# use of init.sh and path_prepend_ is correct, and ensure that every other
# use of init.sh is identical.
# This is useful because help-version cross-checks prog --version
# with $(VERSION), which verifies that its path_prepend_ invocation
# sets PATH correctly.  This is an inexpensive way to ensure that
# the other init.sh-using tests also get it right.
_hv_file ?= $(srcdir)/tests/help-version
_hv_regex_weak ?= ^ *\. .*/init\.sh"
# Fix syntax-highlighters "
_hv_regex_strong ?= ^ *\. "\$${srcdir=\.}/init\.sh"
sc_cross_check_PATH_usage_in_tests:
	@if test -f $(_hv_file); then					\
	  $(GREP) -l 'VERSION mismatch' $(_hv_file) >/dev/null		\
	    || { echo "$@: skipped: no such file: $(_hv_file)" 1>&2;	\
		 exit 0; };						\
	  $(GREP) -lE '$(_hv_regex_strong)' $(_hv_file) >/dev/null	\
	    || { echo "$@: $(_hv_file) lacks conforming use of init.sh" 1>&2; \
		 exit 1; };						\
	  good=$$($(GREP) -E '$(_hv_regex_strong)' $(_hv_file));	\
	  $(VC_LIST_EXCEPT)						\
	    | xargs $(GREP) -lE '$(_hv_regex_weak)'			\
	    | xargs $(GREP) -LFx "$$good"				\
	    | $(GREP) .							\
	    && { printf "$(ME): the above files use"			\
			" path_prepend_ inconsistently\n" 1>&2;		\
		 exit 1; }						\
	    || :;							\
	fi

# BRE regex of file contents to identify a test script.
_test_script_regex ?= \<init\.sh\>

# In tests, use "compare expected actual", not the reverse.
sc_prohibit_reversed_compare_failure:
	@prohibit='\<compare [^ ]+ ([^ ]*exp|/dev/null)'		\
	containing='$(_test_script_regex)'				\
	halt='reversed compare arguments'				\
	  $(_sc_search_regexp)

# #if HAVE_... will evaluate to false for any non numeric string.
# That would be flagged by using -Wundef, however gnulib currently
# tests many undefined macros, and so we can't enable that option.
# So at least preclude common boolean strings as macro values.
sc_Wundef_boolean:
	@prohibit='^#define.*(yes|no|true|false)$$'			\
	in_files='$(CONFIG_INCLUDE)'					\
	halt='Use 0 or 1 for macro values'				\
	  $(_sc_search_regexp)

# Even if you use pathmax.h to guarantee that PATH_MAX is defined, it might
# not be constant, or might overflow a stack.  In general, use PATH_MAX as
# a limit, not an array or alloca size.
sc_prohibit_path_max_allocation:
	@prohibit='(\balloca *\([^)]*|\[[^]]*)\bPATH_MAX'		\
	halt='Avoid stack allocations of size PATH_MAX'			\
	  $(_sc_search_regexp)

sc_vulnerable_makefile_CVE-2009-4029:
	@prohibit='perm -777 -exec chmod a\+rwx|chmod 777 \$$\(distdir\)' \
	in_files='(^|/)Makefile\.in$$'					\
	halt=$$(printf '%s\n'						\
	  'the above files are vulnerable; beware of running'		\
	  '  "make dist*" rules, and upgrade to fixed automake'		\
	  '  see https://bugzilla.redhat.com/show_bug.cgi?id=542609 for details') \
	  $(_sc_search_regexp)

sc_vulnerable_makefile_CVE-2012-3386:
	@prohibit='chmod a\+w \$$\(distdir\)'				\
	in_files='(^|/)Makefile\.in$$'					\
	halt=$$(printf '%s\n'						\
	  'the above files are vulnerable; beware of running'		\
	  '  "make distcheck", and upgrade to fixed automake'		\
	  '  see https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2012-3386 for details') \
	  $(_sc_search_regexp)