libvirt/build-aux/bracket-spacing.pl

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Document bracket whitespace rules & add syntax-check rule This documents the following whitespace rules if(foo) // Bad if (foo) // Good int foo (int wizz) // Bad int foo(int wizz) // Good bar = foo (wizz); // Bad bar = foo(wizz); // Good typedef int (*foo) (int wizz); // Bad typedef int (*foo)(int wizz); // Good int foo( int wizz ); // Bad int foo(int wizz); // Good There is a syntax-check rule extension to validate all these rules. Checking for 'function (...args...)' is quite difficult since it needs to ignore valid usage with keywords like 'if (...test...)' and while/for/switch. It must also ignore source comments and quoted strings. It is not possible todo this with a simple regex in the normal syntax-check style. So a short Perl script is created instead to analyse the source. In practice this works well enough. The only thing it can't cope with is multi-line quoted strings of the form "start of string\ more lines\ more line\ the end" but this can and should be written as "start of string" "more lines" "more line" "the end" with this simple change, the bracket checking script does not have any false positives across libvirt source, provided it is only run against .c files. It is not practical to run it against .h files, since those use whitespace extensively to get alignment (though this is somewhat inconsistent and could arguably be fixed). The only limitation is that it cannot detect a violation where the first arg starts with a '*', eg foo(*wizz); since this generates too many false positives on function typedefs which can't be supressed efficiently. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-10-17 09:25:35 +00:00
#!/usr/bin/perl
#
# bracket-spacing.pl: Report any usage of 'function (..args..)'
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library. If not, see
# <http://www.gnu.org/licenses/>.
#
# Authors:
# Daniel P. Berrange <berrange@redhat.com>
use strict;
use warnings;
my $ret = 0;
my $incomment = 0;
foreach my $file (@ARGV) {
open FILE, $file;
while (defined (my $line = <FILE>)) {
my $data = $line;
# Kill any quoted strongs
$data =~ s,".*?","XXX",g;
# Kill any C++ style comments
$data =~ s,//.*$,//,;
next if $data =~ /^#/;
# Kill contents of multi-line comments
# and detect end of multi-line comments
if ($incomment) {
if ($data =~ m,\*/,) {
$incomment = 0;
$data =~ s,^.*\*/,*/,;
} else {
$data = "";
}
}
# Kill single line comments, and detect
# start of multi-line comments
if ($data =~ m,/\*.*\*/,) {
$data =~ s,/\*.*\*/,/* */,;
} elsif ($data =~ m,/\*,) {
$incomment = 1;
$data =~ s,/\*.*,/*,;
}
# We need to match things like
#
# int foo (int bar, bool wizz);
# foo (bar, wizz);
#
# but not match things like:
#
# typedef int (*foo)(bar wizz)
#
# we can't do this (efficiently) without
# missing things like
#
# foo (*bar, wizz);
#
while ($data =~ /(\w+)\s\((?!\*)/) {
my $kw = $1;
# Allow space after keywords only
if ($kw =~ /^(if|for|while|switch|return)$/) {
$data =~ s/($kw\s\()/XXX(/;
} else {
print "$file:$.: $line";
$ret = 1;
last;
}
}
# Require whitespace immediately after keywords,
# but none after the opening bracket
while ($data =~ /(if|for|while|switch|return)\(/ ||
$data =~ /(if|for|while|switch|return)\s+\(\s/) {
print "$file:$.: $line";
$ret = 1;
last;
}
# Forbid whitespace between )( of a function typedef
while ($data =~ /\(\*\w+\)\s+\(/) {
print "$file:$.: $line";
$ret = 1;
last;
}
# Forbid whitespace following ( or prior to )
while ($data =~ /\S\s+\)/ ||
$data =~ /\(\s+\S/) {
print "$file:$.: $line";
$ret = 1;
last;
}
# Forbid whitespace before ";". Things like below are allowed:
#
# 1) The expression is empty for "for" loop. E.g.
# for (i = 0; ; i++)
#
# 2) An empty statement. E.g.
# while (write(statuswrite, &status, 1) == -1 &&
# errno == EINTR)
# ;
#
# 3) ";" is inside double-quote, I.e, as part of const string. E.g.
# printf("%s", "a ; b\n");
while ($data =~ /[^;\s]\s+;/) {
# Inside the double-quote
if ($data !~ /"[^"]*\s;/) {
print "$file:$.: $line";
$ret = 1;
}
last;
}
Document bracket whitespace rules & add syntax-check rule This documents the following whitespace rules if(foo) // Bad if (foo) // Good int foo (int wizz) // Bad int foo(int wizz) // Good bar = foo (wizz); // Bad bar = foo(wizz); // Good typedef int (*foo) (int wizz); // Bad typedef int (*foo)(int wizz); // Good int foo( int wizz ); // Bad int foo(int wizz); // Good There is a syntax-check rule extension to validate all these rules. Checking for 'function (...args...)' is quite difficult since it needs to ignore valid usage with keywords like 'if (...test...)' and while/for/switch. It must also ignore source comments and quoted strings. It is not possible todo this with a simple regex in the normal syntax-check style. So a short Perl script is created instead to analyse the source. In practice this works well enough. The only thing it can't cope with is multi-line quoted strings of the form "start of string\ more lines\ more line\ the end" but this can and should be written as "start of string" "more lines" "more line" "the end" with this simple change, the bracket checking script does not have any false positives across libvirt source, provided it is only run against .c files. It is not practical to run it against .h files, since those use whitespace extensively to get alignment (though this is somewhat inconsistent and could arguably be fixed). The only limitation is that it cannot detect a violation where the first arg starts with a '*', eg foo(*wizz); since this generates too many false positives on function typedefs which can't be supressed efficiently. Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-10-17 09:25:35 +00:00
}
close FILE;
}
exit $ret;