libvirt/build-aux/syntax-check.mk

#
# Rules for running syntax-check, derived from gnulib's
# maint.mk
#
# Specifically, all shared code should match gnulib commit
#
#   dd2503c8e73621e919e8e214a29c495ac89d8a92 (2022-05-21)
#
# Copyright (C) 2008-2019 Red Hat, Inc.
# Copyright (C) 2001-2022 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
# <http://www.gnu.org/licenses/>.


all:
	@echo "Do not call this file directly, use 'meson test' instead" >&2; \
	exit 1


## ----- ##
## Rules ##
## ----- ##

# Files that should never cause syntax check failures.
VC_LIST_ALWAYS_EXCLUDE_REGEX = \
  \.(po|ico|png)$$

# Avoid uses of write(2).  Either switch to streams (fwrite), or use
# the safewrite wrapper.
sc_avoid_write:
	@prohibit='\<write *\(' \
	exclude='sc_avoid_write' \
	in_vc_files='\.c$$' \
	halt='consider using safewrite instead of write' \
	  $(_sc_search_regexp)

# In debug statements, print flags as bitmask and mode_t as octal.
sc_flags_debug:
	@prohibit='\<mode=%[0-9.]*[diuxo]' \
	halt='use \"0%o\" to debug mode_t values' \
	  $(_sc_search_regexp)
	@prohibit='[Ff]lags=%[0-9.]*l*[dioux]' \
	halt='use \"0x%x\" to debug flag values' \
	  $(_sc_search_regexp)

# Prefer 'unsigned int flags', along with checks for unknown flags.
# For historical reasons, we are stuck with 'unsigned long flags' in
# migration, so check for those known 4 instances and no more in public
# API.  Also check that no flags are marked unused, and 'unsigned' should
# appear before any declaration of a flags variable (achieved by
# prohibiting the word prior to the type from ending in anything other
# than d).  The existence of long long, and of documentation about
# flags, makes the regex in the third test slightly harder.
sc_flags_usage:
	@test "$$(cat $(top_srcdir)/include/libvirt/libvirt-domain.h \
	    $(top_srcdir)/include/libvirt/virterror.h \
	    $(top_srcdir)/include/libvirt/libvirt-qemu.h \
	    $(top_srcdir)/include/libvirt/libvirt-lxc.h \
	    $(top_srcdir)/include/libvirt/libvirt-admin.h \
	  | $(GREP) -c '\(long\|unsigned\) flags')" != 4 && \
	  { echo 'new API should use "unsigned int flags"' 1>&2; \
	    exit 1; } || :
	@prohibit=' flags G_GNUC_UNUSED' \
	exclude='virSecurityDomainImageLabelFlags' \
	halt='flags should be checked with virCheckFlags' \
	  $(_sc_search_regexp)
	@prohibit='^[^@]*([^d] (int|long long)|[^dg] long) flags[;,)]' \
	halt='flags should be unsigned' \
	  $(_sc_search_regexp)

# Avoid functions that should only be called via macro counterparts.
sc_prohibit_internal_functions:
	@prohibit='vir(Free|AllocN?|ReallocN|(Insert|Delete)ElementsN|File(Close|Fclose|Fdopen)) *\(' \
	halt='use VIR_ macros instead of internal functions' \
	  $(_sc_search_regexp)

sc_prohibit_raw_virclassnew:
	@prohibit='virClassNew *\(' \
	halt='use VIR_CLASS_NEW instead of virClassNew' \
	  $(_sc_search_regexp)

# Avoid raw malloc and free, except in documentation comments.
sc_prohibit_raw_allocation:
	@prohibit='^.[^*].*\<((m|c|re)alloc|free) *\([^)]' \
	halt='use VIR_ macros from viralloc.h instead of malloc/free' \
	  $(_sc_search_regexp)

# Avoid functions that can lead to double-close bugs.
sc_prohibit_close:
	@prohibit='([^>.]|^)\<[fp]?close *\(' \
	halt='use VIR_{FORCE_}[F]CLOSE instead of [f]close' \
	  $(_sc_search_regexp)
	@prohibit='\<fdopen *\(' \
	halt='use VIR_FDOPEN instead of fdopen' \
	  $(_sc_search_regexp)

# Prefer virCommand for all child processes.
sc_prohibit_fork_wrappers:
	@prohibit='= *\<(fork|popen|system) *\(' \
	halt='use virCommand for child processes' \
	  $(_sc_search_regexp)

# Prefer g_mkostemp_full with O_CLOEXEC.
sc_prohibit_mkstemp:
	@prohibit='[^"]\<mko?stemps? *\(' \
	in_vc_files='\.[chx]$$' \
	halt='use g_mkstemp_full with O_CLOEXEC instead of mkstemp' \
	  $(_sc_search_regexp)

sc_prohibit_mkdtemp:
	@prohibit='[^"]\<mkdtemp *\(' \
	in_vc_files='\.[chx]$$' \
	halt='use g_mkdtemp instead of mkdtemp' \
	  $(_sc_search_regexp)

# access with X_OK accepts directories, but we can't exec() those.
# access with F_OK or R_OK is okay, though.
sc_prohibit_access_xok:
	@prohibit='access(at)? *\(.*X_OK' \
	in_vc_files='\.[ch]$$' \
	halt='use virFileIsExecutable instead of access(,X_OK)' \
	  $(_sc_search_regexp)

# Use STREQLEN or STRPREFIX rather than comparing strncmp == 0, or != 0.
snp_ = strncmp *\(.+\)
sc_prohibit_strncmp:
	@prohibit='! *strncmp *\(|\<$(snp_) *[!=]=|[!=]= *$(snp_)' \
	exclude=':# *define STR(N?EQLEN|PREFIX)\(' \
	halt='use STREQLEN or STRPREFIX instead of strncmp' \
	  $(_sc_search_regexp)

# strtol and friends are too easy to misuse
sc_prohibit_strtol:
	@prohibit='\bstrto(u?ll?|[ui]max) *\(' \
	exclude='exempt from syntax-check' \
	halt='use virStrToLong_*, not strtol variants' \
	  $(_sc_search_regexp)
	@prohibit='\bstrto[df] *\(' \
	exclude='exempt from syntax-check' \
	halt='use virStrToDouble, not strtod variants' \
	  $(_sc_search_regexp)

# Use g_strdup_printf rather than as'printf since *strp is undefined on error.
# But for plain %s, g_strdup_printf is overkill compared to g_strdup.
sc_prohibit_asprintf:
	@prohibit='\<v?a[s]printf\>' \
	halt='use g_strdup_printf, not asprintf' \
	  $(_sc_search_regexp)
	@prohibit='g_strdup_printf.*, *"%s",' \
	halt='use g_strdup instead of g_strdup_printf with "%s"' \
	  $(_sc_search_regexp)

sc_prohobit_vsnprintf:
	@prohibit='\<vsnprintf\>' \
	in_vc_files='\.[chx]$$' \
	halt='use g_vsnprintf, not vsnprintf' \
	  $(_sc_search_regexp)

sc_prohibit_strdup:
	@prohibit='\<strn?dup\> *\(' \
	halt='use g_str(n)dup, not str(n)dup' \
	  $(_sc_search_regexp)

# Prefer virSetUIDGID.
sc_prohibit_setuid:
	@prohibit='\<set(re)?[ug]id\> *\(' \
	halt='use virSetUIDGID, not raw set*id' \
	  $(_sc_search_regexp)

# Don't compare *id_t against raw -1.
sc_prohibit_risky_id_promotion:
	@prohibit='\b(user|group|[ug]id) *[=!]= *-' \
	halt='cast -1 to ([ug]id_t) before comparing against id' \
	  $(_sc_search_regexp)

sc_prohibit_sprintf:
	@prohibit='\<[s]printf\>' \
	in_vc_files='\.[ch]$$' \
	halt='use g_snprintf, not sprintf' \
	  $(_sc_search_regexp)

sc_prohibit_snprintf:
	@prohibit='\<snprintf\>' \
	halt='use g_snprintf, not snprintf' \
	  $(_sc_search_regexp)

sc_prohibit_readlink:
	@prohibit='\<readlink *\(' \
	halt='use virFileResolveLink, not readlink' \
	  $(_sc_search_regexp)

sc_prohibit_gethostname:
	@prohibit='gethostname *\(' \
	in_vc_files='\.[ch]$$' \
	halt='use virGetHostname, not gethostname' \
	  $(_sc_search_regexp)

sc_prohibit_readdir:
	@prohibit='\b(read|close|open)dir *\(' \
	exclude='exempt from syntax-check' \
	halt='use virDirOpen, virDirRead and g_autoptr(DIR)' \
	  $(_sc_search_regexp)

sc_prohibit_gettext_noop:
	@prohibit='gettext_noop *\(' \
	halt='use N_, not gettext_noop' \
	  $(_sc_search_regexp)

sc_prohibit_PATH_MAX:
	@prohibit='\<PATH_MAX\>' \
	halt='dynamically allocate paths, do not use PATH_MAX' \
	  $(_sc_search_regexp)

include $(top_srcdir)/build-aux/Makefile.nonreentrant
sc_prohibit_nonreentrant:
	@prohibit="\\<(${NON_REENTRANT_RE}) *\\(" \
	exclude='exempt from syntax-check' \
	halt="use re-entrant functions (usually ending with _r)" \
	  $(_sc_search_regexp)

sc_prohibit_select:
	@prohibit='\<select *\(' \
	halt='use poll(), not select()' \
	  $(_sc_search_regexp)

# Prohibit the inclusion of <ctype.h>.
sc_prohibit_ctype_h:
	@prohibit='^# *include  *<ctype\.h>' \
	halt='use Glib g_ascii_* function instead of ctype.h' \
	  $(_sc_search_regexp)

# We have our own wrapper for mocking purposes
sc_prohibit_canonicalize_file_name:
	@prohibit='\<canonicalize_file_name\(' \
	exclude='exempt from syntax-check' \
	halt='use virFileCanonicalizePath() instead of canonicalize_file_name()' \
	  $(_sc_search_regexp)

# qsort from glibc has unstable sort ordering for "equal" members
sc_prohibit_qsort:
	@prohibit='\<(qsort|qsort_r) *\(' \
	exclude='exempt from syntax-check' \
	halt='use g_qsort_with_data instead of qsort' \
	  $(_sc_search_regexp)

# Insist on correct types for [pug]id.
sc_correct_id_types:
	@prohibit='\<(int|long) *[pug]id\>' \
	exclude='exempt from syntax-check' \
	halt='use pid_t for pid, uid_t for uid, gid_t for gid' \
	  $(_sc_search_regexp)

# "const fooPtr a" is the same as "foo * const a", even though it is
# usually desired to have "foo const *a".  It's easier to just prevent
# the confusing mix of typedef vs. const placement.
# Also requires that all 'fooPtr' typedefs are actually pointers.
sc_forbid_const_pointer_typedef:
	@prohibit='(^|[^"])const \w*Ptr' \
	halt='"const fooPtr var" does not declare what you meant' \
	  $(_sc_search_regexp)
	@prohibit='typedef [^(]+ [^*]\w*Ptr\b' \
	halt='use correct style and type for Ptr typedefs' \
	  $(_sc_search_regexp)

# Forbid sizeof foo or sizeof (foo), require sizeof(foo)
sc_size_of_brackets:
	@prohibit='sizeof\s' \
	halt='use sizeof(foo), not sizeof (foo) or sizeof foo' \
	  $(_sc_search_regexp)

# Ensure that no C source file, docs, or rng schema uses TABs for
# indentation.  Also match *.h.in files, to get libvirt.h.in.
space_indent_files=(\.(aug(\.in)?|rng|s?[ch](\.in)?|html.in|py|pl|syms)|tools/.*\.in)
sc_TAB_in_indentation:
	@prohibit='^ *	' \
	in_vc_files='$(space_indent_files)$$' \
	halt='indent with space, not TAB, in C, sh, html, py, syms and RNG schemas' \
	  $(_sc_search_regexp)

ctype_re = isalnum|isalpha|isascii|isblank|iscntrl|isdigit|isgraph|islower\
|isprint|ispunct|isspace|isupper|isxdigit|tolower|toupper

sc_avoid_ctype_macros:
	@prohibit='\b($(ctype_re)) *\(' \
	in_vc_files='\.[ch]$$' \
	halt='use Glib g_ascii_ macros instead of ctype macros' \
	  $(_sc_search_regexp)

sc_avoid_strcase:
	@prohibit='\bstrn?case(cmp|str) *\(' \
	halt='use GLib strcase functions instead of raw strcase functions' \
	  $(_sc_search_regexp)

sc_prohibit_virBufferAdd_with_string_literal:
	@prohibit='\<virBufferAdd *\([^,]+, *"[^"]' \
	halt='use virBufferAddLit, not virBufferAdd, with a string literal' \
	  $(_sc_search_regexp)

sc_prohibit_virBufferAsprintf_with_string_literal:
	@prohibit='\<virBufferAsprintf *\([^,]+, *"([^%"\]|\\.|%%)*"\)' \
	halt='use virBufferAddLit, not virBufferAsprintf, with a string literal' \
	  $(_sc_search_regexp)

sc_forbid_manual_xml_indent:
	@prohibit='virBuffer.*" +<' \
	halt='use virBufferAdjustIndent instead of spaces when indenting xml' \
	  $(_sc_search_regexp)

# dirname and basename from <libgen.h> are not required to be thread-safe
sc_prohibit_libgen:
	@prohibit='( (base|dir)name *\(|include .libgen\.h)' \
	halt='use functions from GLib, not <libgen.h>' \
	  $(_sc_search_regexp)

# raw xmlGetProp requires some nasty casts
sc_prohibit_xmlGetProp:
	@prohibit='\<xmlGetProp *\(' \
	halt='use virXMLPropString, not xmlGetProp' \
	  $(_sc_search_regexp)

# xml(ParseURI|SaveUri) doesn't handle IPv6 URIs well
sc_prohibit_xmlURI:
	@prohibit='\<xml(ParseURI|SaveUri) *\(' \
	halt='use virURI(Parse|Format), not xml(ParseURI|SaveUri)' \
	  $(_sc_search_regexp)

# we don't want old old-style return with parentheses around argument
sc_prohibit_return_as_function:
	@prohibit='\<return *\(([^()]*(\([^()]*\)[^()]*)*)\) *;' \
	halt='avoid extra () with return statements' \
	  $(_sc_search_regexp)

# G_GNUC_UNUSED should only be applied in implementations, not
# header declarations
sc_avoid_g_gnuc_unused_in_header:
	@prohibit='^[^#]*G_GNUC_UNUSED([^:]|$$)' \
	in_vc_files='\.h$$' \
	halt='use G_GNUC_UNUSED in .c rather than .h files' \
	  $(_sc_search_regexp)

sc_prohibit_int_index:
	@prohibit='\<(int|unsigned)\s*\*?index\>(\s|,|;)' \
	halt='use different name than 'index' for declaration' \
	  $(_sc_search_regexp)

sc_prohibit_int_ijk:
	@prohibit='\<(int|unsigned) ([^(=]* )*(i|j|k)\>(\s|,|;)' \
	exclude='exempt from syntax-check' \
	halt='use size_t, not int/unsigned int for loop vars i, j, k' \
	  $(_sc_search_regexp)

sc_prohibit_loop_iijjkk:
	@prohibit='\<(int|unsigned) ([^=]+ )*(ii|jj|kk)\>(\s|,|;)' \
	halt='use i, j, k for loop iterators, not ii, jj, kk' \
	  $(_sc_search_regexp)

# RHEL 5 gcc can't grok "for (int i..."
sc_prohibit_loop_var_decl:
	@prohibit='\<for *\(\w+[ *]+\w+' \
	in_vc_files='\.[ch]$$' \
	halt='declare loop iterators outside the for statement' \
	  $(_sc_search_regexp)

# Use 'bool', not 'int', when assigning true or false
sc_prohibit_int_assign_bool:
	@prohibit='\<int\>.*= *(true|false)' \
	halt='use bool type for boolean values' \
	  $(_sc_search_regexp)

sc_prohibit_unsigned_pid:
	@prohibit='\<unsigned\> [^,=;(]+pid' \
	halt='use signed type for pid values' \
	  $(_sc_search_regexp)

# Many of the function names below came from this filter:
# git grep -B2 '\<_('|grep -E '\.c- *[[:alpha:]_][[:alnum:]_]* ?\(.*[,;]$' \
# |sed 's/.*\.c-  *//'|perl -pe 's/ ?\(.*//'|sort -u \
# |grep -vE '^(if|close|assert|fputc|free|N_|vir.*GetName|.*Unlock|virNodeListDevices|virHashRemoveEntry|freeaddrinfo|.*[fF]ree|xdrmem_create|xmlXPathFreeObject|virUUIDFormat|openvzSetProgramSentinal|polkit_action_unref)$'

msg_gen_function =
msg_gen_function += VIR_ERROR
msg_gen_function += lxcError
msg_gen_function += regerror
msg_gen_function += vah_error
msg_gen_function += vah_warning
msg_gen_function += vboxReportError
msg_gen_function += virGenericReportError
msg_gen_function += virRaiseError
msg_gen_function += virReportError
msg_gen_function += virReportErrorHelper
msg_gen_function += virReportSystemError
msg_gen_function += virLastErrorPrefixMessage

# Uncomment the following and run "ninja test" to see diagnostics
# that are not yet marked for translation, but that need to be rewritten
# so that they are translatable.
# msg_gen_function += fprintf
# msg_gen_function += testError
# msg_gen_function += vshPrint
# msg_gen_function += vshError

space = $(null) $(null)
func_re= ($(subst $(space),|,$(msg_gen_function)))

# 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.
# The sed filters eliminate false-positives like these:
#    _("...: "
#    "%s", _("no storage vol w..."
sc_libvirt_unmarked_diagnostics:
	@prohibit='\<$(func_re) *\([^"]*"[^"]*[a-z]{3}' \
	exclude='_\(' \
	halt='found unmarked diagnostic(s)' \
	  $(_sc_search_regexp)
	@{ $(VC_LIST_EXCEPT) | xargs \
		$(GREP)     -nE '\<$(func_re) *\(.*;$$' /dev/null; \
	   $(VC_LIST_EXCEPT) | xargs \
		$(GREP) -A1 -nE '\<$(func_re) *\(.*,$$' /dev/null; } \
	   | $(SED) -E 's/_\("([^\"]|\\.)+"//;s/"%s"//' \
	   | $(GREP) '"' && \
	  { echo 'found unmarked diagnostic(s)' 1>&2; \
	    exit 1; } || :

# Like the above, but prohibit a newline at the end of a diagnostic.
# This is subject to false positives partly because it naively looks for
# `\n"', which may not be the end of the string, and also because it takes
# two lines of context (the -A2) after the line with the function name.
# FIXME: this rule might benefit from a separate function list, in case
# there are functions to which this one applies but that do not get marked
# diagnostics.
sc_prohibit_newline_at_end_of_diagnostic:
	@$(VC_LIST_EXCEPT) | xargs $(GREP) -A2 -nE \
	    '\<$(func_re) *\(' /dev/null \
	    | $(GREP) '\\n"' \
	  && { echo 'newline at end of message(s)' 1>&2; \
	    exit 1; } || :

# Disallow translated messages on multiple lines, except when
# they end with '\n'.
sc_prohibit_error_message_on_multiple_lines:
	@prohibit='[^N]_\(".*"$$' \
    exclude='\\n"$$' \
	halt='found error message on multiple lines' \
	$(_sc_search_regexp)

# Look for diagnostics that lack a % in the format string, except that we
# allow VIR_ERROR to do this, and ignore functions that take a single
# string rather than a format argument.
sc_prohibit_diagnostic_without_format:
	@{ $(VC_LIST_EXCEPT) | xargs \
		$(GREP)     -nE '\<$(func_re) *\(.*;$$' /dev/null; \
	   $(VC_LIST_EXCEPT) | xargs \
		$(GREP) -A2 -nE '\<$(func_re) *\(.*,$$' /dev/null; } \
	   | $(SED) -rn -e ':l; /[,"]$$/ {N;b l;}' \
		-e '/(vah_(error|warning))/d' \
		-e '/\<$(func_re) *\([^"]*"([^%"]|"\n[^"]*")*"[,)]/p' \
           | $(GREP) -vE 'VIR_ERROR' && \
	  { echo 'found diagnostic without %' 1>&2; \
	    exit 1; } || :

sc_require_permutable_format_in_translation:
	@prohibit='\<N?_ *\("[^"]*%[^%$$ ]*[a-zA-Z][^"]*"' \
	halt='non-permutable format string(s)' \
	  $(_sc_search_regexp)

# The strings "" and "%s" should never be marked for translation.
# Files under tests/ and examples/ should not be translated.
sc_prohibit_useless_translation:
	@prohibit='_\("(%s)?"\)' \
	halt='found useless translation' \
	  $(_sc_search_regexp)
	@prohibit='\<N?_ *\(' \
	in_vc_files='(tests|examples)/' \
	halt='no translations in tests or examples' \
	  $(_sc_search_regexp)

# When splitting a diagnostic across lines, ensure that there is a space
# or \n on one side of the split.
sc_require_whitespace_in_translation:
	@$(VC_LIST_EXCEPT) | xargs $(GREP) -n -A1 '"$$' /dev/null \
	   | $(SED) -ne ':l; /"$$/ {N;b l;}; s/"\n[^"]*"/""/g; s/\\n/ /g' \
		-e '/_(.*[^\ ]""[^\ ]/p' | $(GREP) . && \
	  { echo 'missing whitespace at line split' 1>&2; \
	    exit 1; } || :

# Enforce recommended preprocessor indentation style.
sc_preprocessor_indentation:
	@if cppi --version >/dev/null 2>&1; then \
	  $(VC_LIST_EXCEPT) | $(GREP) -E '\.[ch](\.in)?$$' | xargs cppi -a -c \
	    || { echo 'incorrect preprocessor indentation' 1>&2; \
		exit 1; }; \
	else \
	  echo 'skipping test $@: cppi not installed' 1>&2; \
	fi

# Enforce similar spec file indentation style, by running cppi on a
# (comment-only) C file that mirrors the same layout as the spec file.
sc_spec_indentation:
	@if cppi --version >/dev/null 2>&1; then \
	  for f in $$($(VC_LIST_EXCEPT) | $(GREP) '\.spec\.in$$'); do \
	    $(SED) -e 's|#|// #|; s|%ifn*\(arch\)* |#if a // |' \
		-e 's/%\(else\|endif\|define\)/#\1/' \
		-e 's/^\( *\)\1\1\1#/#\1/' \
		-e 's|^\( *[^#/ ]\)|// \1|; s|^\( */[^/]\)|// \1|' $$f \
	    | cppi -a -c 2>&1 | $(SED) "s|standard input|$$f|"; \
	  done | { if $(GREP) . >&2; then false; else :; fi; } \
	    || { echo 'incorrect preprocessor indentation' 1>&2; \
		exit 1; }; \
	else \
	  echo 'skipping test $@: cppi not installed' 1>&2; \
	fi


# Prefer the new URL listing over the old street address listing when
# calling out where to get a copy of the [L]GPL.  Also, while we have
# to ship COPYING (GPL) alongside COPYING.LESSER (LGPL), we want any
# source file that calls out a top-level file to call out the LGPL
# version.  Note that our typical copyright boilerplate refers to the
# license by name, not by reference to a top-level file.
sc_copyright_usage:
	@prohibit=Boston,' MA' \
	halt='Point to <http://www.gnu.org/licenses/>, not an address' \
	  $(_sc_search_regexp)
	@require='COPYING\.LESSER' \
	containing='COPYING' \
	halt='Refer to COPYING.LESSER for LGPL' \
	  $(_sc_search_regexp)
	@prohibit='COPYING\.LIB' \
	halt='Refer to COPYING.LESSER for LGPL' \
	  $(_sc_search_regexp)

# Some functions/macros produce messages intended solely for developers
# and maintainers.  Do not mark them for translation.
sc_prohibit_gettext_markup:
	@prohibit='\<VIR_(WARN|INFO|DEBUG) *\(_\(' \
	halt='do not mark these strings for translation' \
	  $(_sc_search_regexp)

# Our code is divided into modular subdirectories for a reason, and
# lower-level code must not include higher-level headers.
cross_dirs=$(patsubst $(top_srcdir)/src/%.,%,$(wildcard $(top_srcdir)/src/*/.))
cross_dirs_re=($(subst / ,/|,$(cross_dirs)))
mid_dirs=access|admin|conf|cpu|locking|logging|rpc|security
sc_prohibit_cross_inclusion:
	@for dir in $(cross_dirs); do \
	  case $$dir in \
	    util/) safe="util";; \
	    access/ | conf/) safe="($$dir|conf|util)";; \
	    cpu/| network/| node_device/| rpc/| security/| storage/) \
	      safe="($$dir|util|conf|storage)";; \
	    *) safe="($$dir|$(mid_dirs)|hypervisor|util)";; \
	  esac; \
	  in_vc_files="src/$$dir" \
	  prohibit='^# *include .$(cross_dirs_re)' \
	  exclude="# *include .$$safe" \
	  halt='unsafe cross-directory include' \
	    $(_sc_search_regexp) \
	done

# When converting an enum to a string, make sure that we track any new
# elements added to the enum by using a _LAST marker.
sc_require_enum_last_marker:
	@$(VC_LIST_EXCEPT) | xargs \
		$(GREP) -A1 -nE '^[^#]*VIR_ENUM_IMPL *\(' /dev/null \
	   | $(SED) -ne '/VIR_ENUM_IMPL.*,$$/N' \
	     -e '/VIR_ENUM_IMPL[^,]*,[^,]*,[^,]*[^_,][^L,][^A,][^S,][^T,],/p' \
	     -e '/VIR_ENUM_IMPL[^,]*,[^,]\{0,4\},/p' \
	   | $(GREP) . && \
	  { echo 'enum impl needs _LAST marker on second line' 1>&2; \
	    exit 1; } || :

sc_prohibit_python_without_env:
	@prohibit='#!/usr/.*/py''thon' \
	 halt='always call python via /usr/bin/env' \
	   $(_sc_search_regexp)

# We're intentionally ignoring a few warnings
#
# E302: whitespace before ':'. This is something that is
# desirable when indexing array slices and is used by the
# 'black' formatting tool
#
# E501: Force breaking lines at < 80 characters results in
# some really unnatural code formatting which harms
# readability.
#
# W503: line break before binary operator, because this
# is contrary to what 'black' formatting tool wants
#
# W504: Knuth code style requires the operators "or" and "and" etc
# to be at the start of line in a multi-line conditional.
# This the opposite to what is normal libvirt practice.
#
FLAKE8_IGNORE = E203,E501,W503,W504

sc_flake8:
	@if [ -n "$(FLAKE8)" ]; then \
		DOT_PY=$$($(VC_LIST_EXCEPT) | $(GREP) '\.py$$'); \
		BANG_PY=$$($(VC_LIST_EXCEPT) | xargs grep -l '^#!/usr/bin/env python3$$'); \
		ALL_PY=$$(printf "%s\n%s" "$$DOT_PY" "$$BANG_PY" | sort -u); \
		echo "$$ALL_PY" | xargs $(FLAKE8) --ignore $(FLAKE8_IGNORE) --show-source; \
	else \
		echo 'skipping test $@: flake8 not installed' 1>&2; \
	fi

sc_black:
	if [ -n "$(BLACK)" ]; then \
		DOT_PY=$$($(VC_LIST_EXCEPT) | $(GREP) '\.py$$'); \
		BANG_PY=$$($(VC_LIST_EXCEPT) | xargs grep -l '^#!/usr/bin/env python3$$'); \
		ALL_PY=$$(printf "%s\n%s" "$$DOT_PY" "$$BANG_PY" | sort -u); \
		echo "$$ALL_PY" | xargs --no-run-if-empty $(BLACK) --check; \
	else \
		echo 'skipping test $@: black not installed' 1>&2; \
	fi

# mymain() in test files should use return, not exit, for nicer output
sc_prohibit_exit_in_tests:
	@prohibit='\<exit *\(' \
	in_vc_files='tests/.*\.c$$' \
	exclude='exempt from syntax-check' \
	halt='use return, not exit(), in tests' \
	  $(_sc_search_regexp)

# Don't include "libvirt/*.h" in "" form.
sc_prohibit_include_public_headers_quote:
	@prohibit='# *include *"libvirt/.*\.h"' \
	in_vc_files='\.[ch]$$' \
	halt='Do not include libvirt/*.h in internal source' \
	  $(_sc_search_regexp)

# Don't include "libvirt/*.h" in <> form. Except for external tools,
# e.g. Python binding, examples and tools subdirectories.
sc_prohibit_include_public_headers_brackets:
	@prohibit='# *include *<libvirt/.*\.h>' \
	in_vc_files='\.[ch]$$' \
	halt='Do not include libvirt/*.h in internal source' \
	  $(_sc_search_regexp)

# <config.h> is only needed in .c files; .h files do not need it since
# .c files must include config.h before any other .h.
sc_prohibit_config_h_in_headers:
	@prohibit='^# *include *[<"]config\.h' \
	in_vc_files='\.h$$' \
	halt='headers should not include <config.h>' \
	  $(_sc_search_regexp)

sc_prohibit_unbounded_arrays_in_rpc:
	@prohibit='<>' \
	in_vc_files='\.x$$' \
	halt='Arrays in XDR must have a upper limit set for <NNN>' \
	  $(_sc_search_regexp)

sc_prohibit_atoi:
	@prohibit='\bato(i|f|l|ll|q) *\(' \
	halt='Use virStrToLong* instead of atoi, atol, atof, atoq, atoll' \
	  $(_sc_search_regexp)

sc_prohibit_wrong_filename_in_comment:
	@$(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$'	| xargs awk 'BEGIN { \
	  fail=0; \
	} FNR < 3 { \
	  n=match($$0, /[[:space:]][^[:space:]]*[.][ch][[:space:]:]/); \
	  if (n > 0) { \
	    A=substr($$0, RSTART+1, RLENGTH-2); \
	    n=split(FILENAME, arr, "/"); \
	    if (A != arr[n]) { \
	      print "in " FILENAME ": " A " mentioned in comments "; \
	      fail=1; \
	    } \
	  } \
	} END { \
	  if (fail == 1) { \
	    exit 1; \
	  } \
	}' || { echo 'The file name in comments must match the' \
	    'actual file name' 1>&2; exit 1; }

sc_prohibit_virConnectOpen_in_virsh:
	@prohibit='\bvirConnectOpen[a-zA-Z]* *\(' \
	in_vc_files='tools/virsh-.*\.[ch]$$' \
	halt='Use vshConnect() in virsh instead of virConnectOpen*' \
	  $(_sc_search_regexp)

sc_require_space_before_label:
	@prohibit='^(   ?)?[_a-zA-Z0-9]+:$$' \
	in_vc_files='\.[ch]$$' \
	halt='Top-level labels should be indented by one space' \
	  $(_sc_search_regexp)

# Allow for up to three spaces before the label: this is to avoid running
# into situations where neither this rule nor require_space_before_label
# would apply, eg. a line matching ^[a-zA-Z0-9]+ :$
sc_prohibit_space_in_label:
	@prohibit='^ {0,3}[_a-zA-Z0-9]+ +:$$' \
	in_vc_files='\.[ch]$$' \
	halt='There should be no space between label name and colon' \
	  $(_sc_search_regexp)

# Doesn't catch all cases of mismatched braces across if-else, but it helps
sc_require_if_else_matching_braces:
	@prohibit='(  else( if .*\))? {|} else( if .*\))?$$)' \
	in_vc_files='\.[chx]$$' \
	halt='if one side of if-else uses {}, both sides must use it' \
	  $(_sc_search_regexp)

sc_curly_braces_style:
	@if $(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$' | xargs $(GREP) -nHP \
'^\s*(?!([a-zA-Z_]*for_?each[a-zA-Z_]*) ?\()([_a-zA-Z0-9]+( [_a-zA-Z0-9]+)* ?\()?(\*?[_a-zA-Z0-9]+(,? \*?[_a-zA-Z0-9\[\]]+)+|void)\) ?\{' \
	/dev/null; then \
	  echo 'Non-K&R style used for curly braces around' \
	    'function body' 1>&2; exit 1; \
	fi; \
	if $(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$' | xargs \
	    $(GREP) -A1 -En ' ((if|for|while|switch) \(|(else|do)\b)[^{]*$$' \
	    /dev/null | $(GREP) '^[^ ]*- *{'; then \
	  echo 'Use hanging braces for compound statements' 1>&2; exit 1; \
	fi

sc_prohibit_windows_special_chars_in_filename:
	@$(VC_LIST_EXCEPT) | $(GREP) '[:*?"<>|]' && \
	{ echo 'Windows special chars in filename not allowed' 1>&2; echo exit 1; } || :

sc_prohibit_mixed_case_abbreviations:
	@prohibit='Pci|Usb|Scsi|Vpd' \
	in_vc_files='\.[ch]$$' \
	halt='Use PCI, USB, SCSI, VPD, not Pci, Usb, Scsi, Vpd' \
	  $(_sc_search_regexp)

# Require #include <locale.h> in all files that call setlocale()
sc_require_locale_h:
	@require='include.*locale\.h' \
	containing='setlocale *(' \
	halt='setlocale() requires <locale.h>' \
	  $(_sc_search_regexp)

sc_prohibit_empty_first_line:
	@$(VC_LIST_EXCEPT) | xargs awk 'BEGIN { fail=0; } \
	FNR == 1 { maybe_fail = $$0 == ""; } \
	FNR == 2 { if (maybe_fail == 1) { print FILENAME ":1:"; fail=1; } } \
	END { if (fail == 1) { \
	  print "Prohibited empty first line" > "/dev/stderr"; \
	} exit fail; }'

sc_prohibit_paren_brace:
	@prohibit='\)\{$$' \
	in_vc_files='\.[chx]$$' \
	halt='Put space between closing parenthesis and opening brace' \
	  $(_sc_search_regexp)

# C guarantees that static variables are zero initialized, and some compilers
# waste space by sticking explicit initializers in .data instead of .bss
sc_prohibit_static_zero_init:
	@prohibit='\bstatic\b.*= *(0[^xX0-9]|NULL|false)' \
	in_vc_files='\.[chx](\.in)?$$' \
	halt='static variables do not need explicit zero initialization'\
	  $(_sc_search_regexp)

# FreeBSD exports the "devname" symbol which produces a warning.
sc_prohibit_devname:
	@prohibit='\bdevname\b' \
	exclude='sc_prohibit_devname' \
	halt='avoid using devname as FreeBSD exports the symbol' \
	  $(_sc_search_regexp)

sc_prohibit_system_error_with_vir_err:
	@prohibit='\bvirReportSystemError *\(VIR_ERR_' \
	halt='do not use virReportSystemError with VIR_ERR_* error codes' \
	  $(_sc_search_regexp)

# Rule to prohibit usage of virXXXFree within library, daemon, remote, etc.
# functions. There's a corresponding exclude to allow usage within tests,
# docs, examples, tools, src/libvirt-*.c, and include/libvirt/libvirt-*.h
sc_prohibit_virXXXFree:
	@prohibit='\bvir(Domain|Network|NodeDevice|StorageVol|StoragePool|Stream|Secret|NWFilter|Interface|DomainSnapshot)Free\b' \
	exclude='sc_prohibit_virXXXFree' \
	halt='avoid using virXXXFree, use virObjectUnref instead' \
	  $(_sc_search_regexp)

sc_prohibit_sysconf_pagesize:
	@prohibit='sysconf\(_SC_PAGESIZE' \
	halt='use virGetSystemPageSize[KB] instead of sysconf(_SC_PAGESIZE)' \
	  $(_sc_search_regexp)

sc_prohibit_virSecurityManager:
	@$(VC_LIST_EXCEPT) | $(GREP) 'src/qemu/' | \
		$(GREP) -v 'src/qemu/qemu_security' | \
		xargs $(GREP) -Pn 'virSecurityManager\S*\(' /dev/null && \
		{ echo 'prefer qemuSecurity wrappers' 1>&2; exit 1; } || :

sc_prohibit_pthread_create:
	@prohibit='\bpthread_create\b' \
	exclude='sc_prohibit_pthread_create' \
	halt='avoid using pthread_create, use virThreadCreate instead' \
	  $(_sc_search_regexp)

sc_prohibit_not_streq:
	@prohibit='! *STRN?EQ *\(.*\)' \
	halt='Use STRNEQ instead of !STREQ and STREQ instead of !STRNEQ' \
	  $(_sc_search_regexp)

sc_prohibit_verbose_strcat:
	@prohibit='strncat\([^,]*,\s+([^,]*),\s+strlen\(\1\)\)' \
	in_vc_files='\.[ch]$$' \
	halt='Use strcat(a, b) instead of strncat(a, b, strlen(b))' \
	  $(_sc_search_regexp)

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

sc_prohibit_obj_free_apis_in_virsh:
	@prohibit='\bvir(Domain|DomainSnapshot|Interface|Network|NodeDevice|NWFilter|Secret|StoragePool|StorageVol|Stream)Free\b' \
	in_vc_files='virsh.*\.[ch]$$' \
	exclude='sc_prohibit_obj_free_apis_in_virsh' \
	halt='avoid using public virXXXFree in virsh, use virsh-prefixed wrappers instead' \
	  $(_sc_search_regexp)

# Links in various schemas
http_sites = libvirt.org.*\/schemas\/
http_sites += \.dtd
http_sites += libosinfo
http_sites += localhost
http_sites += rdf:resource
http_sites += schemas.dmtf.org
http_sites += schemas.microsoft.com
http_sites += schemas.xmlsoap.org
http_sites += www.inkscape.org
http_sites += www.innotek.de
http_sites += www.w3.org
http_sites += xmlns

# Links in licenses
http_sites += scripts.sil.org
http_sites += www.gnu.org\/licenses\/
http_sites += www.sun.com

# Example links
http_sites += example.com
http_sites += example.org
http_sites += herp.derp

# HTTP-only sites
http_sites += mah.everybody.org
http_sites += etallen.com

# HTTP-only dead sites accessed via archive.org
http_sites += blog.lystor.org.ua
http_sites += blog.mes-stats.fr
http_sites += www.javvin.com
http_sites += kerneltrap.org

http_re= ($(subst $(space),|,$(http_sites)))

sc_prohibit_http_urls:
	@prohibit='http://\w' \
	exclude="$(http_re)" \
	halt='Links must use https:// protocol' \
	  $(_sc_search_regexp)

sc_prohibit_author:
	@prohibit="(\*|#)\s*(A|a)uthors?:" \
	halt="Author: statements are prohibited in source comments" \
	  $(_sc_search_regexp)

# Alignment is usually achieved through spaces (at least two of them)
# or tabs (at least one of them) right before the trailing backslash
sc_prohibit_backslash_alignment:
	@prohibit='(  |	)\\$$' \
	halt='Do not attempt to right-align backslashes' \
	  $(_sc_search_regexp)

# Some syntax rules pertaining to the usage of cleanup macros
# implementing GNU C's cleanup attribute

# Rule to ensure that variables declared using a cleanup macro are
# always initialized.
sc_require_attribute_cleanup_initialization:
	@prohibit='((g_auto(ptr|free|slist)?)|VIR_AUTOCLOSE) *[^=]+;' \
	in_vc_files='\.[chx]$$' \
	halt='variable declared with a cleanup macro must be initialized' \
	  $(_sc_search_regexp)

# "class" in headers is not good because by default Vim treats it as a keyword
# Let's prohibit it in source files as well.
sc_prohibit_class:
	@prohibit=' +_?class *;' \
	in_vc_files='\.[chx]$$' \
	halt='use klass instead of class or _class' \
	  $(_sc_search_regexp)

# The dirent "d_type" field is non-portable and even when it
# exists some filesystems will only ever return DT_UNKNOWN.
# This field should only be used by code which is exclusively
# run platforms supporting "d_type" and must expect DT_UNKNOWN.
# We blacklist it to discourage accidental usage which has
# happened many times. Add an exclude rule if it is genuinely
# needed and the above restrictions are acceptable.
sc_prohibit_dirent_d_type:
	@prohibit='(->|\.)d_type' \
	in_vc_files='\.[chx]$$' \
	halt='do not use the d_type field in "struct dirent"' \
	  $(_sc_search_regexp)

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)

# 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)

# "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 'use FATAL, WARNING or warning' 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 'found error message ending in period' 1>&2; \
	       exit 1; } \
	  || :

# 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 syntax-check.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 syntax-check.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 'the above files include some other header' \
		'before <config.h>' 1>&2; exit 1; } || :; \
	else :; \
	fi

# 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 "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 getopt.h without an actual use.
sc_prohibit_getopt_without_use:
	@h='getopt.h' re='\<getopt(_long)? *\(' $(_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)

_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)

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


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

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

# prohibit remote references to local file in RST files
sc_avoid_remote_reference_to_local_file:
	@prohibit='<#' \
	in_vc_files='\.rst$$' \
	halt='use local reference within a file' \
	  $(_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 'empty line(s) or no newline at EOF' 1>&2; \
	       exit 1; } \
	  || :


# 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 can
# 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 'doubled words' 1>&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)

# 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)


# 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)

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 =~ /\...?$$/ or next;' \
  -e '	\# Ignore mk files' \
  -e '	$$file =~ /\.mk$$/ and next;' \
  -e '	\# Ignore a .c or .h file with a corresponding .l or .y file' \
  -e '	$$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.
po_file ?= $(top_srcdir)/po/POTFILES

# List of additional files that we want to pick up in our POTFILES
# This is all generated files for RPC code.
generated_files = \
  $(top_builddir)/src/*.[ch] \
  $(top_builddir)/src/*/*.[ch]

_gl_translatable_string_re ?= \b(N?_|gettext *)\([^)"]*("|$$)

# sc_po_check can fail if generated files are not built first
sc_po_check:
	@if test -f $(po_file); then \
	  $(GREP) -E -v '^(#|$$)' $(po_file) | 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_builddir)/||' \
	    | $(SED) 's|^$(_dot_escaped_srcdir)/||' \
	    | sort -u > $@-2; \
	  diff -u -L $(po_file) -L $(po_file) $@-1 $@-2 \
	    || { printf $(fix_po_file_diag) 1>&2; exit 1; }; \
	  rm -f $@-1 $@-2; \
	fi

# #if WITH_... 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)

ifneq ($(_gl-Makefile),)
syntax-check: sc_spacing-check \
	sc_prohibit-duplicate-header sc_mock-noinline sc_group-qemu-caps \
        sc_header-ifdef
	@if ! cppi --version >/dev/null 2>&1; then \
		echo "*****************************************************" >&2; \
		echo "* cppi not installed, some checks have been skipped *" >&2; \
		echo "*****************************************************" >&2; \
	fi; \
	if [ -z "$(FLAKE8)" ]; then \
		echo "*****************************************************" >&2; \
		echo "* flake8 not installed, sc_flake8 has been skipped  *" >&2; \
		echo "*****************************************************" >&2; \
	fi
	if [ -z "$(BLACK)" ]; then \
		echo "*****************************************************" >&2; \
		echo "* black not installed, sc_black has been skipped    *" >&2; \
		echo "*****************************************************" >&2; \
	fi
endif

# Don't include duplicate header in the source (either *.c or *.h)
sc_prohibit-duplicate-header:
	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.[chx]$$' | $(RUNUTF8) xargs \
	$(PYTHON) $(top_srcdir)/scripts/prohibit-duplicate-header.py

sc_spacing-check:
	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.c$$' | xargs \
	$(PERL) $(top_srcdir)/build-aux/check-spacing.pl || \
	  { echo 'incorrect formatting' 1>&2; exit 1; }

sc_mock-noinline:
	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.[ch]$$' | $(RUNUTF8) \
	$(PYTHON) $(top_srcdir)/scripts/mock-noinline.py

sc_header-ifdef:
	$(AM_V_GEN)$(VC_LIST_EXCEPT) | $(GREP) '\.[h]$$' | $(RUNUTF8) xargs \
	$(PYTHON) $(top_srcdir)/scripts/header-ifdef.py

sc_group-qemu-caps:
	$(AM_V_GEN)$(RUNUTF8) $(PYTHON) $(top_srcdir)/scripts/group-qemu-caps.py \
		--check --prefix $(top_srcdir)/

sc_prohibit_enum_impl_with_vir_prefix_in_virsh:
	@prohibit='VIR_ENUM_(IMPL|DECL)\(vir[^s]' \
	in_vc_files='tools/virsh.*\.[ch]$$' \
	halt='avoid "vir" prefix for enums in virsh' \
	  $(_sc_search_regexp)


## ---------- ##
## Exceptions ##
## ---------- ##

exclude_file_name_regexp--sc_avoid_strcase = ^tools/(vsh\.h|nss/libvirt_nss_(leases|macs)\.c)$$

exclude_file_name_regexp--sc_avoid_write = ^src/libvirt-stream\.c$$

exclude_file_name_regexp--sc_gettext_init = \
	^((tests|examples)/|tools/virt-login-shell\.c$$|scripts/rpcgen/tests/test_demo\.c$$)

exclude_file_name_regexp--sc_copyright_usage = \
  ^COPYING(|\.LESSER)$$

exclude_file_name_regexp--sc_flags_usage = \
  ^(build-aux/syntax-check\.mk|docs/|src/util/virnetdevtap\.c$$|tests/((vir(cgroup|pci|test|usb)|nss|qemuxml2argv|qemusecurity)mock|virfilewrapper)\.c$$)

exclude_file_name_regexp--sc_libvirt_unmarked_diagnostics = \
  ^(src/rpc/gendispatch\.pl$$|tests/)

exclude_file_name_regexp--sc_po_check = ^(docs/|src/rpc/gendispatch\.pl$$|tests/commandtest.c$$)

exclude_file_name_regexp--sc_prohibit_PATH_MAX = \
	^(build-aux/syntax-check\.mk|tests/virfilemock.c)$$

exclude_file_name_regexp--sc_prohibit_access_xok = \
	^(src/util/virutil\.c)$$

exclude_file_name_regexp--sc_prohibit_asprintf = \
  ^(build-aux/syntax-check\.mk|examples/|tests/vircgroupmock\.c|tools/virt-login-shell\.c|tools/nss/libvirt_nss\.c$$)

exclude_file_name_regexp--sc_prohibit_strdup = \
  ^(docs/|examples/|tests/virnetserverclientmock.c|tests/commandhelper.c|tools/nss/libvirt_nss_(leases|macs)\.c$$)

exclude_file_name_regexp--sc_prohibit_close = \
  (\.p[yl]$$|\.spec\.in$$|^docs/|^(src/util/vir(file|event)\.c|src/libvirt-stream\.c|tests/(vir.+mock\.c|commandhelper\.c|qemusecuritymock\.c)|tools/nss/libvirt_nss_(leases|macs)\.c)|tools/virt-qemu-qmp-proxy$$)

exclude_file_name_regexp--sc_prohibit_empty_lines_at_EOF = \
  ((^tests/(nodedevmdevctl|viracpi|virhostcpu|virpcitest|virstoragetest|qemunbdkit)data/|docs/js/.*\.js|docs/fonts/.*\.woff|\.diff|tests/virconfdata/no-newline\.conf$$)|\.bin)

exclude_file_name_regexp--sc_prohibit_fork_wrappers = \
  (^(src/(util/(vircommand|virdaemon)|lxc/lxc_controller)|tests/testutils)\.c$$)

exclude_file_name_regexp--sc_prohibit_gethostname = ^src/util/virutil\.c$$

exclude_file_name_regexp--sc_prohibit_internal_functions = \
  ^src/(util/(viralloc|virutil|virfile)\.[hc]|esx/esx_vi\.c)$$

exclude_file_name_regexp--sc_prohibit_raw_virclassnew = \
  ^src/util/virobject\.[hc]$$

exclude_file_name_regexp--sc_prohibit_newline_at_end_of_diagnostic = \
  ^src/rpc/gendispatch\.pl$$

exclude_file_name_regexp--sc_prohibit_error_message_on_multiple_lines = \
  ^(build-aux/syntax-check\.mk|docs/coding-style.rst)

exclude_file_name_regexp--sc_prohibit_nonreentrant = \
  ^((po|tests|examples)/|docs/.*(py|js|html\.in|.rst)|run.in$$|tools/wireshark/util/genxdrstub\.pl|tools/virt-login-shell\.c$$)

exclude_file_name_regexp--sc_prohibit_canonicalize_file_name = \
  ^(build-aux/syntax-check\.mk|tests/virfilemock\.c)$$

exclude_file_name_regexp--sc_prohibit_raw_allocation = \
  ^(docs/advanced-tests\.rst|src/util/viralloc\.[ch]|examples/.*|tests/(securityselinuxhelper|(vircgroup|nss)mock|commandhelper)\.c|tools/wireshark/src/packet-libvirt\.c|tools/nss/libvirt_nss(_leases|_macs)?\.c)$$

exclude_file_name_regexp--sc_prohibit_readlink = \
  ^src/(util/virutil|lxc/lxc_container)\.c$$

exclude_file_name_regexp--sc_prohibit_setuid = ^src/util/virutil\.c|tools/virt-login-shell\.c$$

exclude_file_name_regexp--sc_prohibit_snprintf = \
  ^(build-aux/syntax-check\.mk|docs/coding-style\.rst|tools/virt-login-shell\.c)$$

exclude_file_name_regexp--sc_prohibit_strtol = ^examples/.*$$

exclude_file_name_regexp--sc_prohibit_xmlGetProp = ^src/util/virxml\.c$$

exclude_file_name_regexp--sc_prohibit_xmlURI = ^src/util/viruri\.c$$

exclude_file_name_regexp--sc_prohibit_return_as_function = \.py$$

exclude_file_name_regexp--sc_require_config_h = \
	^(examples/c/.*/.*\.c|tools/virsh-edit\.c|tests/virmockstathelpers\.c|scripts/rpcgen/tests/(test_)?demo\.c)$$

exclude_file_name_regexp--sc_require_config_h_first = \
	^(examples/|tools/virsh-edit\.c$$|tests/virmockstathelpers\.c$$|scripts/rpcgen/tests/test_demo\.c$$)

exclude_file_name_regexp--sc_trailing_blank = \
  /sysinfodata/.*\.data|/virhostcpudata/.*\.cpuinfo$$

exclude_file_name_regexp--sc_unmarked_diagnostics = \
  ^(scripts/apibuild.py|tests/virt-aa-helper-test|docs/js/.*\.js)$$

exclude_file_name_regexp--sc_size_of_brackets = build-aux/syntax-check\.mk

exclude_file_name_regexp--sc_correct_id_types = \
  (^src/locking/lock_protocol.x$$)

exclude_file_name_regexp--sc_prohibit_include_public_headers_quote = \
  ^(src/internal\.h$$|tools/wireshark/src/packet-libvirt.c$$)

exclude_file_name_regexp--sc_prohibit_include_public_headers_brackets = \
  ^(tools/|examples/|include/libvirt/(virterror|libvirt(-(admin|qemu|lxc))?)\.h$$)

exclude_file_name_regexp--sc_prohibit_int_ijk = \
  ^(src/remote_protocol-structs|src/remote/remote_protocol\.x|build-aux/syntax-check\.mk|include/libvirt/libvirt.+|src/admin_protocol-structs|src/admin/admin_protocol\.x)$$

exclude_file_name_regexp--sc_prohibit_unsigned_pid = \
  ^(include/libvirt/.*\.h|src/(qemu/qemu_driver\.c|driver-hypervisor\.h|libvirt(-[a-z]*)?\.c|.*\.x|util/vir(polkit|systemd)\.c)|tests/virpolkittest\.c|tools/virsh-domain\.c)$$

exclude_file_name_regexp--sc_avoid_g_gnuc_unused_in_header = \
  ^(src/util/virlog\.h|src/network/bridge_driver\.h)$$

exclude_file_name_regexp--sc_prohibit_mixed_case_abbreviations = \
  ^src/(vbox/vbox_CAPI.*.h|esx/esx_vi.(c|h)|esx/esx_storage_backend_iscsi.c)$$

exclude_file_name_regexp--sc_prohibit_empty_first_line = \
  ^tests/vmwareverdata/fusion-5.0.3.txt|scripts/rpcgen/tests/demo\.c$$

exclude_file_name_regexp--sc_prohibit_useless_translation = \
  ^tests/virpolkittest.c

exclude_file_name_regexp--sc_prohibit_devname = \
  ^(tools/virsh.pod|build-aux/syntax-check\.mk|docs/.*|tests/qemucapabilitiesdata/.*)$$

exclude_file_name_regexp--sc_prohibit_virXXXFree = \
  ^(docs/|tests/|examples/|tools/|build-aux/syntax-check\.mk|src/test/test_driver.c|src/libvirt_public.syms|include/libvirt/libvirt-(domain|network|nodedev|storage|stream|secret|nwfilter|interface|domain-snapshot).h|src/libvirt-(domain|qemu|network|nodedev|storage|stream|secret|nwfilter|interface|domain-snapshot).c|src/qemu/qemu_shim.c$$)

exclude_file_name_regexp--sc_prohibit_sysconf_pagesize = \
  ^(build-aux/syntax-check\.mk|src/util/vir(hostmem|util)\.c)$$

exclude_file_name_regexp--sc_prohibit_pthread_create = \
  ^(build-aux/syntax-check\.mk|src/util/virthread\.c|tests/.*)$$

exclude_file_name_regexp--sc_prohibit_readdir = \
  ^(tests/(.*mock|virfilewrapper)\.c|tools/nss/libvirt_nss\.c)$$

exclude_file_name_regexp--sc_prohibit_dirent_d_type = \
  ^(src/util/vircgroup.c)$

exclude_file_name_regexp--sc_prohibit_strcmp = \
  ^(tools/nss/libvirt_nss.*\.c|tools/virt-login-shell\.c)

exclude_file_name_regexp--sc_prohibit_select = \
  ^build-aux/syntax-check\.mk|src/util/vireventglibwatch\.c|tests/meson\.build$$

exclude_file_name_regexp--sc_header-ifdef = \
  ^scripts/rpcgen/tests/demo\.[ch]$$

exclude_file_name_regexp--sc_black = \
  ^tools/|src/|tests/|ci/|run\.in|scripts/[^/]*\.py

exclude_file_name_regexp--sc_spacing-check = \
  ^scripts/rpcgen/tests/test_demo\.[ch]$$

## -------------- ##
## Implementation ##
## -------------- ##

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

VC_LIST = cd $(top_srcdir); git ls-tree -r 'HEAD:' | \
          sed -n "s|^100[^	]*.||p"

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

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

# In order to be able to consistently filter "."-relative names,
# (i.e., with no $(top_srcdir) prefix), this definition is careful to
# remove any $(top_srcdir) prefix, and to restore what it removes.
_sc_excl = \
  $(or $(exclude_file_name_regexp--$@),^$$)
VC_LIST_EXCEPT = \
  $(VC_LIST) | $(GREP) -Ev -e '($(VC_LIST_ALWAYS_EXCLUDE_REGEX)|$(_sc_excl))' \
	$(_prepend_srcdir_prefix)

# 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

# _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 $(top_srcdir)".  When neither is specified, use all files that
#     are under version control.
#
#  containing | non_containing
#
#     Select the files (non) containing strings matching this regexp.
#     If both arguments are specified then CONTAINING takes
#     precedence.
#
#  with_grep_options
#
#     Extra options for grep.
#
#  ignore_case
#
#     Ignore case.
#
#  halt
#
#     Message to display before to halting execution.
#
# Finally, you may exempt files based on an ERE matching file names.
# For example, to exempt from the sc_space_tab check all files with the
# .diff suffix, set this Make variable:
#
# exclude_file_name_regexp--sc_space_tab = \.diff$
#
# 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' "$$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=$$(find $(top_srcdir) | $(GREP) -E "$$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