From 0f1e61e5b3641c657f2ac3b45ad4ee88e67e8727 Mon Sep 17 00:00:00 2001
From: Mauro Carvalho Chehab <[email protected]>
Date: Wed, 17 Jul 2024 06:23:00 +0200
Subject: [PATCH 53/85] scripts/checkpatch.pl: some improvements to reduce
 false positives

- camelcase is OK for printk inttypes.h;
- strncpy is OK;
- accept up to 120 chars on lines without warnings;
- stop complaining about "BACKTRACE=" strings split on multiple lines;
- remove PREFER_DEFINED_ATTRIBUTE_MACRO, as this is kernel-specific;
- remove MACRO_ARG_REUSE, as this applies mostly to multithreading;
- don't warn on using do{} while(0) with single line statements;

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
---
 scripts/checkpatch.pl | 103 +++---------------------------------------
 1 file changed, 7 insertions(+), 96 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 7ebc4ad..1c8afbc 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -55,7 +55,7 @@ my %ignore_type = ();
 my @ignore = ();
 my $help = 0;
 my $configuration_file = ".checkpatch.conf";
-my $max_line_length = 100;
+my $max_line_length = 120;
 my $ignore_perl_version = 0;
 my $minimum_perl_version = 5.10.0;
 my $min_conf_desc_length = 4;
@@ -5636,12 +5636,10 @@ sub process {
 #CamelCase
 			if ($var !~ /^$Constant$/ &&
 			    $var =~ /[A-Z][a-z]|[a-z][A-Z]/ &&
+#Ignore inttypes.h macros
+			    $var !~ /^_*PRI(b|d|i|o|u|x)(8|16|32|64|PTR)/ &&
 #Ignore some autogenerated defines and enum values
 			    $var !~ /^(?:[A-Z]+_){1,5}[A-Z]{1,3}[a-z]/ &&
-#Ignore Page<foo> variants
-			    $var !~ /^(?:Clear|Set|TestClear|TestSet|)Page[A-Z]/ &&
-#Ignore ETHTOOL_LINK_MODE_<foo> variants
-			    $var !~ /^ETHTOOL_LINK_MODE_/ &&
 #Ignore SI style variants like nS, mV and dB
 #(ie: max_uV, regulator_min_uA_show, RANGE_mA_VALUE)
 			    $var !~ /^(?:[a-z0-9_]*|[A-Z0-9_]*)?_?[a-z][A-Z](?:_[a-z0-9_]+|_[A-Z0-9_]+)?$/ &&
@@ -5825,10 +5823,6 @@ sub process {
 				$tmp_stmt =~ s/\#+\s*$arg\b//g;
 				$tmp_stmt =~ s/\b$arg\s*\#\#//g;
 				my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
-				if ($use_cnt > 1) {
-					CHK("MACRO_ARG_REUSE",
-					    "Macro argument reuse '$arg' - possible side-effects?\n" . "$herectx");
-				    }
 # check if any macro arguments may have other precedence issues
 				if ($tmp_stmt =~ m/($Operators)?\s*\b$arg\b\s*($Operators)?/m &&
 				    ((defined($1) && $1 ne ',') ||
@@ -5894,11 +5888,6 @@ sub process {
 				my $cnt = statement_rawlines($ctx);
 				my $herectx = get_stat_here($linenr, $cnt, $here);
 
-				if (($stmts =~ tr/;/;/) == 1 &&
-				    $stmts !~ /^\s*(if|while|for|switch)\b/) {
-					WARN("SINGLE_STATEMENT_DO_WHILE_MACRO",
-					     "Single statement macros should not use a do {} while (0) loop\n" . "$herectx");
-				}
 				if (defined $semis && $semis ne "") {
 					WARN("DO_WHILE_MACRO_WITH_TRAILING_SEMICOLON",
 					     "do {} while (0) macros should not be semicolon terminated\n" . "$herectx");
@@ -6058,11 +6047,10 @@ sub process {
 
 # Check for user-visible strings broken across lines, which breaks the ability
 # to grep for the string.  Make exceptions when the previous string ends in a
-# newline (multiple lines in one string constant) or '\t', '\r', ';', or '{'
-# (common in inline assembly) or is a octal \123 or hexadecimal \xaf value
+# newline (multiple lines in one string constant) or '\t', '\r' or '='
 		if ($line =~ /^\+\s*$String/ &&
 		    $prevline =~ /"\s*$/ &&
-		    $prevrawline !~ /(?:\\(?:[ntr]|[0-7]{1,3}|x[0-9a-fA-F]{1,2})|;\s*|\{\s*)"\s*$/) {
+		    $prevrawline !~ /(?:\\(?:[ntr])|=)"\s*$/) {
 			if (WARN("SPLIT_STRING",
 				 "quoted string split across lines\n" . $hereprev) &&
 				     $fix &&
@@ -6508,71 +6496,6 @@ sub process {
 			}
 		}
 
-# Check for compiler attributes
-		if ($realfile !~ m@\binclude/uapi/@ &&
-		    $rawline =~ /\b__attribute__\s*\(\s*($balanced_parens)\s*\)/) {
-			my $attr = $1;
-			$attr =~ s/\s*\(\s*(.*)\)\s*/$1/;
-
-			my %attr_list = (
-				"alias"				=> "__alias",
-				"aligned"			=> "__aligned",
-				"always_inline"			=> "__always_inline",
-				"assume_aligned"		=> "__assume_aligned",
-				"cold"				=> "__cold",
-				"const"				=> "__attribute_const__",
-				"copy"				=> "__copy",
-				"designated_init"		=> "__designated_init",
-				"externally_visible"		=> "__visible",
-				"format"			=> "printf|scanf",
-				"gnu_inline"			=> "__gnu_inline",
-				"malloc"			=> "__malloc",
-				"mode"				=> "__mode",
-				"no_caller_saved_registers"	=> "__no_caller_saved_registers",
-				"noclone"			=> "__noclone",
-				"noinline"			=> "noinline",
-				"nonstring"			=> "__nonstring",
-				"noreturn"			=> "__noreturn",
-				"packed"			=> "__packed",
-				"pure"				=> "__pure",
-				"section"			=> "__section",
-				"used"				=> "__used",
-				"weak"				=> "__weak"
-			);
-
-			while ($attr =~ /\s*(\w+)\s*(${balanced_parens})?/g) {
-				my $orig_attr = $1;
-				my $params = '';
-				$params = $2 if defined($2);
-				my $curr_attr = $orig_attr;
-				$curr_attr =~ s/^[\s_]+|[\s_]+$//g;
-				if (exists($attr_list{$curr_attr})) {
-					my $new = $attr_list{$curr_attr};
-					if ($curr_attr eq "format" && $params) {
-						$params =~ /^\s*\(\s*(\w+)\s*,\s*(.*)/;
-						$new = "__$1\($2";
-					} else {
-						$new = "$new$params";
-					}
-					if (WARN("PREFER_DEFINED_ATTRIBUTE_MACRO",
-						 "Prefer $new over __attribute__(($orig_attr$params))\n" . $herecurr) &&
-					    $fix) {
-						my $remove = "\Q$orig_attr\E" . '\s*' . "\Q$params\E" . '(?:\s*,\s*)?';
-						$fixed[$fixlinenr] =~ s/$remove//;
-						$fixed[$fixlinenr] =~ s/\b__attribute__/$new __attribute__/;
-						$fixed[$fixlinenr] =~ s/\}\Q$new\E/} $new/;
-						$fixed[$fixlinenr] =~ s/ __attribute__\s*\(\s*\(\s*\)\s*\)//;
-					}
-				}
-			}
-
-			# Check for __attribute__ unused, prefer __always_unused or __maybe_unused
-			if ($attr =~ /^_*unused/) {
-				WARN("PREFER_DEFINED_ATTRIBUTE_MACRO",
-				     "__always_unused or __maybe_unused is preferred over __attribute__((__unused__))\n" . $herecurr);
-			}
-		}
-
 # Check for __attribute__ weak, or __weak declarations (may have link issues)
 		if ($perl_version_ok &&
 		    $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ &&
@@ -6752,22 +6675,10 @@ sub process {
 #			}
 #		}
 
-# strcpy uses that should likely be strscpy
+# strcpy should be avoided
 		if ($line =~ /\bstrcpy\s*\(/) {
 			WARN("STRCPY",
-			     "Prefer strscpy over strcpy - see: https://github.com/KSPP/linux/issues/88\n" . $herecurr);
-		}
-
-# strlcpy uses that should likely be strscpy
-		if ($line =~ /\bstrlcpy\s*\(/) {
-			WARN("STRLCPY",
-			     "Prefer strscpy over strlcpy - see: https://github.com/KSPP/linux/issues/89\n" . $herecurr);
-		}
-
-# strncpy uses that should likely be strscpy or strscpy_pad
-		if ($line =~ /\bstrncpy\s*\(/) {
-			WARN("STRNCPY",
-			     "Prefer strscpy, strscpy_pad, or __nonstring over strncpy - see: https://github.com/KSPP/linux/issues/90\n" . $herecurr);
+			     "Please avoid strcpy\n" . $herecurr);
 		}
 
 # ethtool_sprintf uses that should likely be ethtool_puts
-- 
2.33.1