zfs-builds-mm/zfs-2.0.0-rc6/scripts/cstyle.pl

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2020-11-15 11:35:49 +01:00
#!/usr/bin/env perl
#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#
# Copyright 2016 Nexenta Systems, Inc.
#
# Copyright 2008 Sun Microsystems, Inc. All rights reserved.
# Use is subject to license terms.
#
# @(#)cstyle 1.58 98/09/09 (from shannon)
#ident "%Z%%M% %I% %E% SMI"
#
# cstyle - check for some common stylistic errors.
#
# cstyle is a sort of "lint" for C coding style.
# It attempts to check for the style used in the
# kernel, sometimes known as "Bill Joy Normal Form".
#
# There's a lot this can't check for, like proper indentation
# of code blocks. There's also a lot more this could check for.
#
# A note to the non perl literate:
#
# perl regular expressions are pretty much like egrep
# regular expressions, with the following special symbols
#
# \s any space character
# \S any non-space character
# \w any "word" character [a-zA-Z0-9_]
# \W any non-word character
# \d a digit [0-9]
# \D a non-digit
# \b word boundary (between \w and \W)
# \B non-word boundary
#
require 5.0;
use warnings;
use IO::File;
use Getopt::Std;
use strict;
my $usage =
"usage: cstyle [-cghpvCP] [-o constructs] file ...
-c check continuation indentation inside functions
-g print github actions' workflow commands
-h perform heuristic checks that are sometimes wrong
-p perform some of the more picky checks
-v verbose
-C don't check anything in header block comments
-P check for use of non-POSIX types
-o constructs
allow a comma-separated list of optional constructs:
doxygen allow doxygen-style block comments (/** /*!)
splint allow splint-style lint comments (/*@ ... @*/)
";
my %opts;
if (!getopts("cgho:pvCP", \%opts)) {
print $usage;
exit 2;
}
my $check_continuation = $opts{'c'};
my $github_workflow = $opts{'g'} || $ENV{'CI'};
my $heuristic = $opts{'h'};
my $picky = $opts{'p'};
my $verbose = $opts{'v'};
my $ignore_hdr_comment = $opts{'C'};
my $check_posix_types = $opts{'P'};
my $doxygen_comments = 0;
my $splint_comments = 0;
if (defined($opts{'o'})) {
for my $x (split /,/, $opts{'o'}) {
if ($x eq "doxygen") {
$doxygen_comments = 1;
} elsif ($x eq "splint") {
$splint_comments = 1;
} else {
print "cstyle: unrecognized construct \"$x\"\n";
print $usage;
exit 2;
}
}
}
my ($filename, $line, $prev); # shared globals
my $fmt;
my $hdr_comment_start;
if ($verbose) {
$fmt = "%s: %d: %s\n%s\n";
} else {
$fmt = "%s: %d: %s\n";
}
if ($doxygen_comments) {
# doxygen comments look like "/*!" or "/**"; allow them.
$hdr_comment_start = qr/^\s*\/\*[\!\*]?$/;
} else {
$hdr_comment_start = qr/^\s*\/\*$/;
}
# Note, following must be in single quotes so that \s and \w work right.
my $typename = '(int|char|short|long|unsigned|float|double' .
'|\w+_t|struct\s+\w+|union\s+\w+|FILE)';
# mapping of old types to POSIX compatible types
my %old2posix = (
'unchar' => 'uchar_t',
'ushort' => 'ushort_t',
'uint' => 'uint_t',
'ulong' => 'ulong_t',
'u_int' => 'uint_t',
'u_short' => 'ushort_t',
'u_long' => 'ulong_t',
'u_char' => 'uchar_t',
'quad' => 'quad_t'
);
my $lint_re = qr/\/\*(?:
ARGSUSED[0-9]*|NOTREACHED|LINTLIBRARY|VARARGS[0-9]*|
CONSTCOND|CONSTANTCOND|CONSTANTCONDITION|EMPTY|
FALLTHRU|FALLTHROUGH|LINTED.*?|PRINTFLIKE[0-9]*|
PROTOLIB[0-9]*|SCANFLIKE[0-9]*|CSTYLED.*?
)\*\//x;
my $splint_re = qr/\/\*@.*?@\*\//x;
my $warlock_re = qr/\/\*\s*(?:
VARIABLES\ PROTECTED\ BY|
MEMBERS\ PROTECTED\ BY|
ALL\ MEMBERS\ PROTECTED\ BY|
READ-ONLY\ VARIABLES:|
READ-ONLY\ MEMBERS:|
VARIABLES\ READABLE\ WITHOUT\ LOCK:|
MEMBERS\ READABLE\ WITHOUT\ LOCK:|
LOCKS\ COVERED\ BY|
LOCK\ UNNEEDED\ BECAUSE|
LOCK\ NEEDED:|
LOCK\ HELD\ ON\ ENTRY:|
READ\ LOCK\ HELD\ ON\ ENTRY:|
WRITE\ LOCK\ HELD\ ON\ ENTRY:|
LOCK\ ACQUIRED\ AS\ SIDE\ EFFECT:|
READ\ LOCK\ ACQUIRED\ AS\ SIDE\ EFFECT:|
WRITE\ LOCK\ ACQUIRED\ AS\ SIDE\ EFFECT:|
LOCK\ RELEASED\ AS\ SIDE\ EFFECT:|
LOCK\ UPGRADED\ AS\ SIDE\ EFFECT:|
LOCK\ DOWNGRADED\ AS\ SIDE\ EFFECT:|
FUNCTIONS\ CALLED\ THROUGH\ POINTER|
FUNCTIONS\ CALLED\ THROUGH\ MEMBER|
LOCK\ ORDER:
)/x;
my $err_stat = 0; # exit status
if ($#ARGV >= 0) {
foreach my $arg (@ARGV) {
my $fh = new IO::File $arg, "r";
if (!defined($fh)) {
printf "%s: can not open\n", $arg;
} else {
&cstyle($arg, $fh);
close $fh;
}
}
} else {
&cstyle("<stdin>", *STDIN);
}
exit $err_stat;
my $no_errs = 0; # set for CSTYLED-protected lines
sub err($) {
my ($error) = @_;
unless ($no_errs) {
if ($verbose) {
printf $fmt, $filename, $., $error, $line;
} else {
printf $fmt, $filename, $., $error;
}
if ($github_workflow) {
printf "::error file=%s,line=%s::%s\n", $filename, $., $error;
}
$err_stat = 1;
}
}
sub err_prefix($$) {
my ($prevline, $error) = @_;
my $out = $prevline."\n".$line;
unless ($no_errs) {
if ($verbose) {
printf $fmt, $filename, $., $error, $out;
} else {
printf $fmt, $filename, $., $error;
}
$err_stat = 1;
}
}
sub err_prev($) {
my ($error) = @_;
unless ($no_errs) {
if ($verbose) {
printf $fmt, $filename, $. - 1, $error, $prev;
} else {
printf $fmt, $filename, $. - 1, $error;
}
$err_stat = 1;
}
}
sub cstyle($$) {
my ($fn, $filehandle) = @_;
$filename = $fn; # share it globally
my $in_cpp = 0;
my $next_in_cpp = 0;
my $in_comment = 0;
my $in_header_comment = 0;
my $comment_done = 0;
my $in_warlock_comment = 0;
my $in_function = 0;
my $in_function_header = 0;
my $function_header_full_indent = 0;
my $in_declaration = 0;
my $note_level = 0;
my $nextok = 0;
my $nocheck = 0;
my $in_string = 0;
my ($okmsg, $comment_prefix);
$line = '';
$prev = '';
reset_indent();
line: while (<$filehandle>) {
s/\r?\n$//; # strip return and newline
# save the original line, then remove all text from within
# double or single quotes, we do not want to check such text.
$line = $_;
#
# C allows strings to be continued with a backslash at the end of
# the line. We translate that into a quoted string on the previous
# line followed by an initial quote on the next line.
#
# (we assume that no-one will use backslash-continuation with character
# constants)
#
$_ = '"' . $_ if ($in_string && !$nocheck && !$in_comment);
#
# normal strings and characters
#
s/'([^\\']|\\[^xX0]|\\0[0-9]*|\\[xX][0-9a-fA-F]*)'/''/g;
s/"([^\\"]|\\.)*"/\"\"/g;
#
# detect string continuation
#
if ($nocheck || $in_comment) {
$in_string = 0;
} else {
#
# Now that all full strings are replaced with "", we check
# for unfinished strings continuing onto the next line.
#
$in_string =
(s/([^"](?:"")*)"([^\\"]|\\.)*\\$/$1""/ ||
s/^("")*"([^\\"]|\\.)*\\$/""/);
}
#
# figure out if we are in a cpp directive
#
$in_cpp = $next_in_cpp || /^\s*#/; # continued or started
$next_in_cpp = $in_cpp && /\\$/; # only if continued
# strip off trailing backslashes, which appear in long macros
s/\s*\\$//;
# an /* END CSTYLED */ comment ends a no-check block.
if ($nocheck) {
if (/\/\* *END *CSTYLED *\*\//) {
$nocheck = 0;
} else {
reset_indent();
next line;
}
}
# a /*CSTYLED*/ comment indicates that the next line is ok.
if ($nextok) {
if ($okmsg) {
err($okmsg);
}
$nextok = 0;
$okmsg = 0;
if (/\/\* *CSTYLED.*\*\//) {
/^.*\/\* *CSTYLED *(.*) *\*\/.*$/;
$okmsg = $1;
$nextok = 1;
}
$no_errs = 1;
} elsif ($no_errs) {
$no_errs = 0;
}
# check length of line.
# first, a quick check to see if there is any chance of being too long.
if (($line =~ tr/\t/\t/) * 7 + length($line) > 80) {
# yes, there is a chance.
# replace tabs with spaces and check again.
my $eline = $line;
1 while $eline =~
s/\t+/' ' x (length($&) * 8 - length($`) % 8)/e;
if (length($eline) > 80) {
err("line > 80 characters");
}
}
# ignore NOTE(...) annotations (assumes NOTE is on lines by itself).
if ($note_level || /\b_?NOTE\s*\(/) { # if in NOTE or this is NOTE
s/[^()]//g; # eliminate all non-parens
$note_level += s/\(//g - length; # update paren nest level
next;
}
# a /* BEGIN CSTYLED */ comment starts a no-check block.
if (/\/\* *BEGIN *CSTYLED *\*\//) {
$nocheck = 1;
}
# a /*CSTYLED*/ comment indicates that the next line is ok.
if (/\/\* *CSTYLED.*\*\//) {
/^.*\/\* *CSTYLED *(.*) *\*\/.*$/;
$okmsg = $1;
$nextok = 1;
}
if (/\/\/ *CSTYLED/) {
/^.*\/\/ *CSTYLED *(.*)$/;
$okmsg = $1;
$nextok = 1;
}
# universal checks; apply to everything
if (/\t +\t/) {
err("spaces between tabs");
}
if (/ \t+ /) {
err("tabs between spaces");
}
if (/\s$/) {
err("space or tab at end of line");
}
if (/[^ \t(]\/\*/ && !/\w\(\/\*.*\*\/\);/) {
err("comment preceded by non-blank");
}
# is this the beginning or ending of a function?
# (not if "struct foo\n{\n")
if (/^\{$/ && $prev =~ /\)\s*(const\s*)?(\/\*.*\*\/\s*)?\\?$/) {
$in_function = 1;
$in_declaration = 1;
$in_function_header = 0;
$function_header_full_indent = 0;
$prev = $line;
next line;
}
if (/^\}\s*(\/\*.*\*\/\s*)*$/) {
if ($prev =~ /^\s*return\s*;/) {
err_prev("unneeded return at end of function");
}
$in_function = 0;
reset_indent(); # we don't check between functions
$prev = $line;
next line;
}
if ($in_function_header && ! /^ (\w|\.)/ ) {
if (/^\{\}$/ # empty functions
|| /;/ #run function with multiline arguments
|| /#/ #preprocessor commands
|| /^[^\s\\]*\(.*\)$/ #functions without ; at the end
|| /^$/ #function declaration can't have empty line
) {
$in_function_header = 0;
$function_header_full_indent = 0;
} elsif ($prev =~ /^__attribute__/) { #__attribute__((*))
$in_function_header = 0;
$function_header_full_indent = 0;
$prev = $line;
next line;
} elsif ($picky && ! (/^\t/ && $function_header_full_indent != 0)) {
err("continuation line should be indented by 4 spaces");
}
}
#
# If this matches something of form "foo(", it's probably a function
# definition, unless it ends with ") bar;", in which case it's a declaration
# that uses a macro to generate the type.
#
if (/^\w+\(/ && !/\) \w+;/) {
$in_function_header = 1;
if (/\($/) {
$function_header_full_indent = 1;
}
}
if ($in_function_header && /^\{$/) {
$in_function_header = 0;
$function_header_full_indent = 0;
$in_function = 1;
}
if ($in_function_header && /\);$/) {
$in_function_header = 0;
$function_header_full_indent = 0;
}
if ($in_function_header && /\{$/ ) {
if ($picky) {
err("opening brace on same line as function header");
}
$in_function_header = 0;
$function_header_full_indent = 0;
$in_function = 1;
next line;
}
if ($in_warlock_comment && /\*\//) {
$in_warlock_comment = 0;
$prev = $line;
next line;
}
# a blank line terminates the declarations within a function.
# XXX - but still a problem in sub-blocks.
if ($in_declaration && /^$/) {
$in_declaration = 0;
}
if ($comment_done) {
$in_comment = 0;
$in_header_comment = 0;
$comment_done = 0;
}
# does this looks like the start of a block comment?
if (/$hdr_comment_start/) {
if (!/^\t*\/\*/) {
err("block comment not indented by tabs");
}
$in_comment = 1;
/^(\s*)\//;
$comment_prefix = $1;
if ($comment_prefix eq "") {
$in_header_comment = 1;
}
$prev = $line;
next line;
}
# are we still in the block comment?
if ($in_comment) {
if (/^$comment_prefix \*\/$/) {
$comment_done = 1;
} elsif (/\*\//) {
$comment_done = 1;
err("improper block comment close")
unless ($ignore_hdr_comment && $in_header_comment);
} elsif (!/^$comment_prefix \*[ \t]/ &&
!/^$comment_prefix \*$/) {
err("improper block comment")
unless ($ignore_hdr_comment && $in_header_comment);
}
}
if ($in_header_comment && $ignore_hdr_comment) {
$prev = $line;
next line;
}
# check for errors that might occur in comments and in code.
# allow spaces to be used to draw pictures in all comments.
if (/[^ ] / && !/".* .*"/ && !$in_comment) {
err("spaces instead of tabs");
}
if (/^ / && !/^ \*[ \t\/]/ && !/^ \*$/ &&
(!/^ (\w|\.)/ || $in_function != 0)) {
err("indent by spaces instead of tabs");
}
if (/^\t+ [^ \t\*]/ || /^\t+ \S/ || /^\t+ \S/) {
err("continuation line not indented by 4 spaces");
}
if (/$warlock_re/ && !/\*\//) {
$in_warlock_comment = 1;
$prev = $line;
next line;
}
if (/^\s*\/\*./ && !/^\s*\/\*.*\*\// && !/$hdr_comment_start/) {
err("improper first line of block comment");
}
if ($in_comment) { # still in comment, don't do further checks
$prev = $line;
next line;
}
if ((/[^(]\/\*\S/ || /^\/\*\S/) &&
!(/$lint_re/ || ($splint_comments && /$splint_re/))) {
err("missing blank after open comment");
}
if (/\S\*\/[^)]|\S\*\/$/ &&
!(/$lint_re/ || ($splint_comments && /$splint_re/))) {
err("missing blank before close comment");
}
if (/\/\/\S/) { # C++ comments
err("missing blank after start comment");
}
# check for unterminated single line comments, but allow them when
# they are used to comment out the argument list of a function
# declaration.
if (/\S.*\/\*/ && !/\S.*\/\*.*\*\// && !/\(\/\*/) {
err("unterminated single line comment");
}
if (/^(#else|#endif|#include)(.*)$/) {
$prev = $line;
if ($picky) {
my $directive = $1;
my $clause = $2;
# Enforce ANSI rules for #else and #endif: no noncomment
# identifiers are allowed after #endif or #else. Allow
# C++ comments since they seem to be a fact of life.
if ((($1 eq "#endif") || ($1 eq "#else")) &&
($clause ne "") &&
(!($clause =~ /^\s+\/\*.*\*\/$/)) &&
(!($clause =~ /^\s+\/\/.*$/))) {
err("non-comment text following " .
"$directive (or malformed $directive " .
"directive)");
}
}
next line;
}
#
# delete any comments and check everything else. Note that
# ".*?" is a non-greedy match, so that we don't get confused by
# multiple comments on the same line.
#
s/\/\*.*?\*\///g;
s/\/\/.*$//; # C++ comments
# delete any trailing whitespace; we have already checked for that.
s/\s*$//;
# following checks do not apply to text in comments.
if (/[^<>\s][!<>=]=/ || /[^<>][!<>=]=[^\s,]/ ||
(/[^->]>[^,=>\s]/ && !/[^->]>$/) ||
(/[^<]<[^,=<\s]/ && !/[^<]<$/) ||
/[^<\s]<[^<]/ || /[^->\s]>[^>]/) {
err("missing space around relational operator");
}
if (/\S>>=/ || /\S<<=/ || />>=\S/ || /<<=\S/ || /\S[-+*\/&|^%]=/ ||
(/[^-+*\/&|^%!<>=\s]=[^=]/ && !/[^-+*\/&|^%!<>=\s]=$/) ||
(/[^!<>=]=[^=\s]/ && !/[^!<>=]=$/)) {
# XXX - should only check this for C++ code
# XXX - there are probably other forms that should be allowed
if (!/\soperator=/) {
err("missing space around assignment operator");
}
}
if (/[,;]\S/ && !/\bfor \(;;\)/) {
err("comma or semicolon followed by non-blank");
}
# allow "for" statements to have empty "while" clauses
if (/\s[,;]/ && !/^[\t]+;$/ && !/^\s*for \([^;]*; ;[^;]*\)/) {
err("comma or semicolon preceded by blank");
}
if (/^\s*(&&|\|\|)/) {
err("improper boolean continuation");
}
if (/\S *(&&|\|\|)/ || /(&&|\|\|) *\S/) {
err("more than one space around boolean operator");
}
if (/\b(for|if|while|switch|sizeof|return|case)\(/) {
err("missing space between keyword and paren");
}
if (/(\b(for|if|while|switch|return)\b.*){2,}/ && !/^#define/) {
# multiple "case" and "sizeof" allowed
err("more than one keyword on line");
}
if (/\b(for|if|while|switch|sizeof|return|case)\s\s+\(/ &&
!/^#if\s+\(/) {
err("extra space between keyword and paren");
}
# try to detect "func (x)" but not "if (x)" or
# "#define foo (x)" or "int (*func)();"
if (/\w\s\(/) {
my $s = $_;
# strip off all keywords on the line
s/\b(for|if|while|switch|return|case|sizeof)\s\(/XXX(/g;
s/#elif\s\(/XXX(/g;
s/^#define\s+\w+\s+\(/XXX(/;
# do not match things like "void (*f)();"
# or "typedef void (func_t)();"
s/\w\s\(+\*/XXX(*/g;
s/\b($typename|void)\s+\(+/XXX(/og;
if (/\w\s\(/) {
err("extra space between function name and left paren");
}
$_ = $s;
}
# try to detect "int foo(x)", but not "extern int foo(x);"
# XXX - this still trips over too many legitimate things,
# like "int foo(x,\n\ty);"
# if (/^(\w+(\s|\*)+)+\w+\(/ && !/\)[;,](\s|)*$/ &&
# !/^(extern|static)\b/) {
# err("return type of function not on separate line");
# }
# this is a close approximation
if (/^(\w+(\s|\*)+)+\w+\(.*\)(\s|)*$/ &&
!/^(extern|static)\b/) {
err("return type of function not on separate line");
}
if (/^#define /) {
err("#define followed by space instead of tab");
}
if (/^\s*return\W[^;]*;/ && !/^\s*return\s*\(.*\);/) {
err("unparenthesized return expression");
}
if (/\bsizeof\b/ && !/\bsizeof\s*\(.*\)/) {
err("unparenthesized sizeof expression");
}
if (/\(\s/) {
err("whitespace after left paren");
}
# Allow "for" statements to have empty "continue" clauses.
# Allow right paren on its own line unless we're being picky (-p).
if (/\s\)/ && !/^\s*for \([^;]*;[^;]*; \)/ && ($picky || !/^\s*\)/)) {
err("whitespace before right paren");
}
if (/^\s*\(void\)[^ ]/) {
err("missing space after (void) cast");
}
if (/\S\{/ && !/\{\{/) {
err("missing space before left brace");
}
if ($in_function && /^\s+\{/ &&
($prev =~ /\)\s*$/ || $prev =~ /\bstruct\s+\w+$/)) {
err("left brace starting a line");
}
if (/\}(else|while)/) {
err("missing space after right brace");
}
if (/\}\s\s+(else|while)/) {
err("extra space after right brace");
}
if (/\b_VOID\b|\bVOID\b|\bSTATIC\b/) {
err("obsolete use of VOID or STATIC");
}
if (/\b$typename\*/o) {
err("missing space between type name and *");
}
if (/^\s+#/) {
err("preprocessor statement not in column 1");
}
if (/^#\s/) {
err("blank after preprocessor #");
}
if (/!\s*(strcmp|strncmp|bcmp)\s*\(/) {
err("don't use boolean ! with comparison functions");
}
#
# We completely ignore, for purposes of indentation:
# * lines outside of functions
# * preprocessor lines
#
if ($check_continuation && $in_function && !$in_cpp) {
process_indent($_);
}
if ($picky) {
# try to detect spaces after casts, but allow (e.g.)
# "sizeof (int) + 1", "void (*funcptr)(int) = foo;", and
# "int foo(int) __NORETURN;"
if ((/^\($typename( \*+)?\)\s/o ||
/\W\($typename( \*+)?\)\s/o) &&
!/sizeof\s*\($typename( \*)?\)\s/o &&
!/\($typename( \*+)?\)\s+=[^=]/o) {
err("space after cast");
}
if (/\b$typename\s*\*\s/o &&
!/\b$typename\s*\*\s+const\b/o) {
err("unary * followed by space");
}
}
if ($check_posix_types) {
# try to detect old non-POSIX types.
# POSIX requires all non-standard typedefs to end in _t,
# but historically these have been used.
if (/\b(unchar|ushort|uint|ulong|u_int|u_short|u_long|u_char|quad)\b/) {
err("non-POSIX typedef $1 used: use $old2posix{$1} instead");
}
}
if ($heuristic) {
# cannot check this everywhere due to "struct {\n...\n} foo;"
if ($in_function && !$in_declaration &&
/\}./ && !/\}\s+=/ && !/\{.*\}[;,]$/ && !/\}(\s|)*$/ &&
!/\} (else|while)/ && !/\}\}/) {
err("possible bad text following right brace");
}
# cannot check this because sub-blocks in
# the middle of code are ok
if ($in_function && /^\s+\{/) {
err("possible left brace starting a line");
}
}
if (/^\s*else\W/) {
if ($prev =~ /^\s*\}$/) {
err_prefix($prev,
"else and right brace should be on same line");
}
}
$prev = $line;
}
if ($prev eq "") {
err("last line in file is blank");
}
}
#
# Continuation-line checking
#
# The rest of this file contains the code for the continuation checking
# engine. It's a pretty simple state machine which tracks the expression
# depth (unmatched '('s and '['s).
#
# Keep in mind that the argument to process_indent() has already been heavily
# processed; all comments have been replaced by control-A, and the contents of
# strings and character constants have been elided.
#
my $cont_in; # currently inside of a continuation
my $cont_off; # skipping an initializer or definition
my $cont_noerr; # suppress cascading errors
my $cont_start; # the line being continued
my $cont_base; # the base indentation
my $cont_first; # this is the first line of a statement
my $cont_multiseg; # this continuation has multiple segments
my $cont_special; # this is a C statement (if, for, etc.)
my $cont_macro; # this is a macro
my $cont_case; # this is a multi-line case
my @cont_paren; # the stack of unmatched ( and [s we've seen
sub
reset_indent()
{
$cont_in = 0;
$cont_off = 0;
}
sub
delabel($)
{
#
# replace labels with tabs. Note that there may be multiple
# labels on a line.
#
local $_ = $_[0];
while (/^(\t*)( *(?:(?:\w+\s*)|(?:case\b[^:]*)): *)(.*)$/) {
my ($pre_tabs, $label, $rest) = ($1, $2, $3);
$_ = $pre_tabs;
while ($label =~ s/^([^\t]*)(\t+)//) {
$_ .= "\t" x (length($2) + length($1) / 8);
}
$_ .= ("\t" x (length($label) / 8)).$rest;
}
return ($_);
}
sub
process_indent($)
{
require strict;
local $_ = $_[0]; # preserve the global $_
s///g; # No comments
s/\s+$//; # Strip trailing whitespace
return if (/^$/); # skip empty lines
# regexps used below; keywords taking (), macros, and continued cases
my $special = '(?:(?:\}\s*)?else\s+)?(?:if|for|while|switch)\b';
my $macro = '[A-Z_][A-Z_0-9]*\(';
my $case = 'case\b[^:]*$';
# skip over enumerations, array definitions, initializers, etc.
if ($cont_off <= 0 && !/^\s*$special/ &&
(/(?:(?:\b(?:enum|struct|union)\s*[^\{]*)|(?:\s+=\s*))\{/ ||
(/^\s*\{/ && $prev =~ /=\s*(?:\/\*.*\*\/\s*)*$/))) {
$cont_in = 0;
$cont_off = tr/{/{/ - tr/}/}/;
return;
}
if ($cont_off) {
$cont_off += tr/{/{/ - tr/}/}/;
return;
}
if (!$cont_in) {
$cont_start = $line;
if (/^\t* /) {
err("non-continuation indented 4 spaces");
$cont_noerr = 1; # stop reporting
}
$_ = delabel($_); # replace labels with tabs
# check if the statement is complete
return if (/^\s*\}?$/);
return if (/^\s*\}?\s*else\s*\{?$/);
return if (/^\s*do\s*\{?$/);
return if (/\{$/);
return if (/\}[,;]?$/);
# Allow macros on their own lines
return if (/^\s*[A-Z_][A-Z_0-9]*$/);
# cases we don't deal with, generally non-kosher
if (/\{/) {
err("stuff after {");
return;
}
# Get the base line, and set up the state machine
/^(\t*)/;
$cont_base = $1;
$cont_in = 1;
@cont_paren = ();
$cont_first = 1;
$cont_multiseg = 0;
# certain things need special processing
$cont_special = /^\s*$special/? 1 : 0;
$cont_macro = /^\s*$macro/? 1 : 0;
$cont_case = /^\s*$case/? 1 : 0;
} else {
$cont_first = 0;
# Strings may be pulled back to an earlier (half-)tabstop
unless ($cont_noerr || /^$cont_base / ||
(/^\t*(?: )?(?:gettext\()?\"/ && !/^$cont_base\t/)) {
err_prefix($cont_start,
"continuation should be indented 4 spaces");
}
}
my $rest = $_; # keeps the remainder of the line
#
# The split matches 0 characters, so that each 'special' character
# is processed separately. Parens and brackets are pushed and
# popped off the @cont_paren stack. For normal processing, we wait
# until a ; or { terminates the statement. "special" processing
# (if/for/while/switch) is allowed to stop when the stack empties,
# as is macro processing. Case statements are terminated with a :
# and an empty paren stack.
#
foreach $_ (split /[^\(\)\[\]\{\}\;\:]*/) {
next if (length($_) == 0);
# rest contains the remainder of the line
my $rxp = "[^\Q$_\E]*\Q$_\E";
$rest =~ s/^$rxp//;
if (/\(/ || /\[/) {
push @cont_paren, $_;
} elsif (/\)/ || /\]/) {
my $cur = $_;
tr/\)\]/\(\[/;
my $old = (pop @cont_paren);
if (!defined($old)) {
err("unexpected '$cur'");
$cont_in = 0;
last;
} elsif ($old ne $_) {
err("'$cur' mismatched with '$old'");
$cont_in = 0;
last;
}
#
# If the stack is now empty, do special processing
# for if/for/while/switch and macro statements.
#
next if (@cont_paren != 0);
if ($cont_special) {
if ($rest =~ /^\s*\{?$/) {
$cont_in = 0;
last;
}
if ($rest =~ /^\s*;$/) {
err("empty if/for/while body ".
"not on its own line");
$cont_in = 0;
last;
}
if (!$cont_first && $cont_multiseg == 1) {
err_prefix($cont_start,
"multiple statements continued ".
"over multiple lines");
$cont_multiseg = 2;
} elsif ($cont_multiseg == 0) {
$cont_multiseg = 1;
}
# We've finished this section, start
# processing the next.
goto section_ended;
}
if ($cont_macro) {
if ($rest =~ /^$/) {
$cont_in = 0;
last;
}
}
} elsif (/\;/) {
if ($cont_case) {
err("unexpected ;");
} elsif (!$cont_special) {
err("unexpected ;") if (@cont_paren != 0);
if (!$cont_first && $cont_multiseg == 1) {
err_prefix($cont_start,
"multiple statements continued ".
"over multiple lines");
$cont_multiseg = 2;
} elsif ($cont_multiseg == 0) {
$cont_multiseg = 1;
}
if ($rest =~ /^$/) {
$cont_in = 0;
last;
}
if ($rest =~ /^\s*special/) {
err("if/for/while/switch not started ".
"on its own line");
}
goto section_ended;
}
} elsif (/\{/) {
err("{ while in parens/brackets") if (@cont_paren != 0);
err("stuff after {") if ($rest =~ /[^\s}]/);
$cont_in = 0;
last;
} elsif (/\}/) {
err("} while in parens/brackets") if (@cont_paren != 0);
if (!$cont_special && $rest !~ /^\s*(while|else)\b/) {
if ($rest =~ /^$/) {
err("unexpected }");
} else {
err("stuff after }");
}
$cont_in = 0;
last;
}
} elsif (/\:/ && $cont_case && @cont_paren == 0) {
err("stuff after multi-line case") if ($rest !~ /$^/);
$cont_in = 0;
last;
}
next;
section_ended:
# End of a statement or if/while/for loop. Reset
# cont_special and cont_macro based on the rest of the
# line.
$cont_special = ($rest =~ /^\s*$special/)? 1 : 0;
$cont_macro = ($rest =~ /^\s*$macro/)? 1 : 0;
$cont_case = 0;
next;
}
$cont_noerr = 0 if (!$cont_in);
}