[PATCH] Scripts: checkpatch.pl: Fix incorrect warning in multi-line seq_printf()

[PATCH] Scripts: checkpatch.pl: Fix incorrect warning in multi-line seq_printf()

[Rashika Kheria]

This patch fixes the following incorrect warning given by checkpatch.pl
in case of multi-line seq_printf() statements-

"WARNING: Prefer seq_puts to seq_printf"

The previous code block producing the above warning was evaluating on line
by line basis and hence was printing a warning if the format specifier
was absent in the first line.

In this patch, we maintain a state flag $is_seq_printf_block indicating
that the same seq_printf() statement is continuing in the next line and
throw a warning if no format specifier is found in any of the lines as
indicated by flag $has_format_specifier. 

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
---
 scripts/checkpatch.pl |   24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 66cad50..954568f 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -13,6 +13,9 @@ $P =~ s@.*/@@g;
 
 my $V = '0.32';
 
+my $is_seq_printf_block = 0;
+my $has_format_specifier = 0;
+
 use Getopt::Long qw(:config no_auto_abbrev);
 
 my $quiet = 0;
@@ -3903,14 +3906,23 @@ sub string_find_replace {
 		}
 
 # check for seq_printf uses that could be seq_puts
-		if ($line =~ /\bseq_printf\s*\(/) {
+		if ($line =~ /\bseq_printf\s*\(/ || $is_seq_printf_block) {
 			my $fmt = get_quoted_string($line, $rawline);
-			if ($fmt !~ /[^\\]\%/) {
-				if (WARN("PREFER_SEQ_PUTS",
-					 "Prefer seq_puts to seq_printf\n" . $herecurr) &&
-				    $fix) {
-					$fixed[$linenr - 1] =~ s/\bseq_printf\b/seq_puts/;
+			if ($fmt =~ /[^\\]\%/) {
+				$has_format_specifier = 1;
+			}
+			if ($line =~ m/\;$/) {
+				$is_seq_printf_block = 0;
+				if ($has_format_specifier == 0) {
+					if (WARN("PREFER_SEQ_PUTS",
+						 "Prefer seq_puts to seq_printf\n" . $herecurr) &&
+					    $fix) {
+						$fixed[$linenr - 1] =~ s/\bseq_printf\b/seq_puts/;
+					}
 				}
+				$has_format_specifier = 0;
+			} else {
+				$is_seq_printf_block = 1;
 			}
 		}
 
-- 
1.7.9.5

Re: [PATCH] Scripts: checkpatch.pl: Fix incorrect warning in multi-line seq_printf()

[Joe Perches]

On Tue, 2013-10-29 at 03:02 +0530, Rashika Kheria wrote:
> This patch fixes the following incorrect warning given by checkpatch.pl
> in case of multi-line seq_printf() statements-

I believe this is already fixed in -next

>From 7f1b7c2810888bba02311ec75b19e0cbd598ef83 Mon Sep 17 00:00:00 2001
From: Joe Perches <joe@perches.com>
Date: Fri, 27 Sep 2013 10:14:51 +1000
Subject: [PATCH] checkpatch: update seq_<foo> tests

seq_vprintf, seq_printf and seq_puts are logging functions and should be
allowed to exceed the maximium line length.

Add maximum line length exceptions for these functions.

Also, suggesting seq_printf conversions to seq_puts should be tested for
arguments after the format.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 scripts/checkpatch.pl | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index c03e427..42567bc 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -323,7 +323,8 @@ our $logFunctions = qr{(?x:
 	(?:[a-z0-9]+_){1,2}(?:printk|emerg|alert|crit|err|warning|warn|notice|info|debug|dbg|vdbg|devel|cont|WARN)(?:_ratelimited|_once|)|
 	WARN(?:_RATELIMIT|_ONCE|)|
 	panic|
-	MODULE_[A-Z_]+
+	MODULE_[A-Z_]+|
+	seq_vprintf|seq_printf|seq_puts
 )};
 
 our $signature_tags = qr{(?xi:
@@ -3909,9 +3910,9 @@ sub string_find_replace {
 		}
 
 # check for seq_printf uses that could be seq_puts
-		if ($line =~ /\bseq_printf\s*\(/) {
+		if ($sline =~ /\bseq_printf\s*\(.*"\s*\)\s*;\s*$/) {
 			my $fmt = get_quoted_string($line, $rawline);
-			if ($fmt !~ /[^\\]\%/) {
+			if ($fmt ne "" && $fmt !~ /[^\\]\%/) {
 				if (WARN("PREFER_SEQ_PUTS",
 					 "Prefer seq_puts to seq_printf\n" . $herecurr) &&
 				    $fix) {