checkpatch: add checks for do {} while (0) macro misuses

These types of macros should not be used for either a single statement
nor should the macro end with a semi-colon.

Add tests for these conditions.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joe Perches 2012-07-30 14:41:24 -07:00 committed by Linus Torvalds
parent 66c80b6077
commit b13edf7ff2

View file

@ -2988,6 +2988,45 @@ sub process {
}
}
# do {} while (0) macro tests:
# single-statement macros do not need to be enclosed in do while (0) loop,
# macro should not end with a semicolon
if ($^V && $^V ge 5.10.0 &&
$realfile !~ m@/vmlinux.lds.h$@ &&
$line =~ /^.\s*\#\s*define\s+$Ident(\()?/) {
my $ln = $linenr;
my $cnt = $realcnt;
my ($off, $dstat, $dcond, $rest);
my $ctx = '';
($dstat, $dcond, $ln, $cnt, $off) =
ctx_statement_block($linenr, $realcnt, 0);
$ctx = $dstat;
$dstat =~ s/\\\n.//g;
if ($dstat =~ /^\+\s*#\s*define\s+$Ident\s*${balanced_parens}\s*do\s*{(.*)\s*}\s*while\s*\(\s*0\s*\)\s*([;\s]*)\s*$/) {
my $stmts = $2;
my $semis = $3;
$ctx =~ s/\n*$//;
my $cnt = statement_rawlines($ctx);
my $herectx = $here . "\n";
for (my $n = 0; $n < $cnt; $n++) {
$herectx .= raw_line($linenr, $n) . "\n";
}
if (($stmts =~ tr/;/;/) == 1) {
WARN("SINGLE_STATEMENT_DO_WHILE_MACRO",
"Single statement macros should not use a do {} while (0) loop\n" . "$herectx");
}
if (defined $semis && $semis ne "") {
WARN("DO_WHILE_MACRO_WITH_TRAILING_SEMICOLON",
"do {} while (0) macros should not be semicolon terminated\n" . "$herectx");
}
}
}
# make sure symbols are always wrapped with VMLINUX_SYMBOL() ...
# all assignments may have only one of the following with an assignment:
# .