From 0cd7e93685a125f97b1f1f085c0b7ed6c70a2cb6 Mon Sep 17 00:00:00 2001
From: Christian Loos <cloos@netsandbox.de>
Date: Tue, 30 Aug 2016 17:20:56 +0200
Subject: [PATCH] fix "Don't modify $_ in list functions"

---
 mysqltuner.pl | 58 ++++++++++++++++++++++++++++++++-------------------
 1 file changed, 37 insertions(+), 21 deletions(-)

diff --git a/mysqltuner.pl b/mysqltuner.pl
index 0b133d6..9e0d8eb 100755
--- a/mysqltuner.pl
+++ b/mysqltuner.pl
@@ -1026,8 +1026,12 @@ sub get_all_vars {
 }
 
 sub remove_cr {
-    map { s/\n$//g; } @_;
-    map { s/^\s+$//g; } @_;
+    return map {
+        my $line = $_;
+        $line =~ s/\n$//g;
+        $line =~ s/^\s+$//g;
+        $line;
+    } @_;
 }
 
 sub remove_empty {
@@ -1039,7 +1043,7 @@ sub get_file_contents {
     open(my $fh, "<", $file) or die "Can't open $file for read: $!";
     my @lines = <$fh>;
     close $fh or die "Cannot close $file: $!";
-    remove_cr \@lines;
+    @lines = remove_cr @lines;
     return @lines;
 }
 
@@ -1084,9 +1088,11 @@ sub cve_recommendations {
 
 sub get_opened_ports {
     my @opened_ports = `netstat -ltn`;
-    map {
-        s/.*:(\d+)\s.*$/$1/;
-        s/\D//g;
+    @opened_ports = map {
+        my $v = $_;
+        $v =~ s/.*:(\d+)\s.*$/$1/;
+        $v =~ s/\D//g;
+        $v;
     } @opened_ports;
     @opened_ports = sort { $a <=> $b } grep { !/^$/ } @opened_ports;
     debugprint Dumper \@opened_ports;
@@ -1111,16 +1117,18 @@ sub get_process_memory {
 
 sub get_other_process_memory {
     my @procs = `ps eaxo pid,command`;
-    map {
-        s/.*PID.*//;
-        s/.*mysqld.*//;
-        s/.*\[.*\].*//;
-        s/^\s+$//g;
-        s/.*PID.*CMD.*//;
-        s/.*systemd.*//;
+    @procs = map {
+        my $v = $_;
+        $v =~ s/.*PID.*//;
+        $v =~ s/.*mysqld.*//;
+        $v =~ s/.*\[.*\].*//;
+        $v =~ s/^\s+$//g;
+        $v =~ s/.*PID.*CMD.*//;
+        $v =~ s/.*systemd.*//;
+        $v =~ s/\s*?(\d+)\s*.*/$1/g;
+        $v;
     } @procs;
-    map { s/\s*?(\d+)\s*.*/$1/g; } @procs;
-    remove_cr @procs;
+    @procs = remove_cr @procs;
     @procs = remove_empty @procs;
     my $totalMemOther = 0;
     map { $totalMemOther += get_process_memory($_); } @procs;
@@ -1162,7 +1170,11 @@ sub get_fs_info() {
     my @sinfo = `df -P | grep '%'`;
     my @iinfo = `df -Pi| grep '%'`;
     shift @iinfo;
-    map { s/.*\s(\d+)%\s+(.*)/$1\t$2/g } @sinfo;
+    @sinfo = map {
+        my $v= $_;
+        $v =~ s/.*\s(\d+)%\s+(.*)/$1\t$2/g;
+        $v;
+    } @sinfo;
     foreach my $info (@sinfo) {
         next if $info =~ m{(\d+)\t/(run|dev|sys|proc)($|/)};
         if ( $info =~ /(\d+)\t(.*)/ ) {
@@ -1177,7 +1189,11 @@ sub get_fs_info() {
         }
     }
 
-    map { s/.*\s(\d+)%\s+(.*)/$1\t$2/g } @iinfo;
+    @iinfo = map {
+        my $v = $_;
+        $v =~ s/.*\s(\d+)%\s+(.*)/$1\t$2/g;
+        $v;
+    } @iinfo;
     foreach my $info (@iinfo) {
         next if $info =~ m{(\d+)\t/(run|dev|sys|proc)($|/)};
         if ( $info =~ /(\d+)\t(.*)/ ) {
@@ -1217,7 +1233,7 @@ sub infocmd {
     my $cmd = "@_";
     debugprint "CMD: $cmd";
     my @result = `$cmd`;
-    remove_cr @result;
+    @result = remove_cr @result;
     for my $l (@result) {
         infoprint "$l";
     }
@@ -1227,7 +1243,7 @@ sub infocmd_tab {
     my $cmd = "@_";
     debugprint "CMD: $cmd";
     my @result = `$cmd`;
-    remove_cr @result;
+    @result = remove_cr @result;
     for my $l (@result) {
         infoprint "\t$l";
     }
@@ -1236,7 +1252,7 @@ sub infocmd_tab {
 sub infocmd_one {
     my $cmd    = "@_";
     my @result = `$cmd`;
-    remove_cr @result;
+    @result = remove_cr @result;
     return join ', ', @result;
 }
 
@@ -3197,7 +3213,7 @@ sub get_wsrep_options {
     return () unless defined $myvar{'wsrep_provider_options'};
 
     my @galera_options = split /;/, $myvar{'wsrep_provider_options'};
-    remove_cr @galera_options;
+    @galera_options = remove_cr @galera_options;
     @galera_options = remove_empty @galera_options;
     debugprint Dumper( \@galera_options );
     return @galera_options;