Perl's chop / chomp considered bad, use a regexp instead
authorRichard Levitte <levitte@openssl.org>
Thu, 11 Feb 2016 20:47:30 +0000 (21:47 +0100)
committerRichard Levitte <levitte@openssl.org>
Thu, 11 Feb 2016 21:11:48 +0000 (22:11 +0100)
Once upon a time, there was chop, which somply chopped off the last
character of $_ or a given variable, and it was used to take off the
EOL character (\n) of strings.

... but then, you had to check for the presence of such character.

So came chomp, the better chop which checks for \n before chopping it
off.  And this worked well, as long as Perl made internally sure that
all EOLs were converted to \n.

These days, though, there seems to be a mixture of perls, so lines
from files in the "wrong" environment might have \r\n as EOL, or just
\r (Mac OS, unless I'm misinformed).

So it's time we went for the more generic variant and use s|\R$||, the
better chomp which recognises all kinds of known EOLs and chops them
off.

A few chops were left alone, as they are use as surgical tools to
remove one last slash or one last comma.

NOTE: \R came with perl 5.10.0.  It means that from now on, our
scripts will fail with any older version.

Reviewed-by: Rich Salz <rsalz@openssl.org>
18 files changed:
VMS/VMSify-conf.pl
VMS/translatesyms.pl
apps/CA.pl.in
crypto/lhash/num.pl
crypto/objects/obj_dat.pl
crypto/objects/objects.pl
crypto/objects/objxref.pl
crypto/perlasm/x86_64-xlate.pl
util/check-buildinfo.pl
util/extract-names.pl
util/files.pl
util/fipslink.pl
util/mk1mf.pl
util/mkdef.pl
util/mkerr.pl
util/mkfiles.pl
util/selftest.pl
util/sp-diff.pl

index d3be6a2..9890362 100644 (file)
@@ -7,7 +7,7 @@ my @directory_vars = ( "dir", "certs", "crl_dir", "new_certs_dir" );
 my @file_vars = ( "database", "certificate", "serial", "crlnumber",
                  "crl", "private_key", "RANDFILE" );
 while(<STDIN>) {
-    chomp;
+    s|\R$||;
     foreach my $d (@directory_vars) {
        if (/^(\s*\#?\s*${d}\s*=\s*)\.\/([^\s\#]*)([\s\#].*)$/) {
            $_ = "$1sys\\\$disk:\[.$2$3";
index 8ffdbd8..de3db6c 100644 (file)
@@ -28,7 +28,7 @@ my %translations = ();
 open DEMANGLER_DATA, $ARGV[0]
     or die "Couldn't open $ARGV[0]: $!\n";
 while(<DEMANGLER_DATA>) {
-    chomp;
+    s|\R$||;
     (my $translated, my $original) = split /\$/;
     $translations{$original} = $translated.'$';
 }
index 52a97d7..fbba457 100644 (file)
@@ -121,7 +121,7 @@ if ($WHAT eq '-newcert' ) {
     # ask user for existing CA certificate
     print "CA certificate filename (or enter to create)\n";
     $FILE = <STDIN>;
-    chop $FILE if $FILE;
+    $FILE = s|\R$|| if $FILE;
     if ($FILE) {
         copy_pemfile($FILE,"${CATOP}/private/$CAKEY", "PRIVATE");
         copy_pemfile($FILE,"${CATOP}/$CACERT", "CERTIFICATE");
index 30fedf9..4440a99 100644 (file)
@@ -5,7 +5,7 @@
 while (<>)
        {
        next unless /^node/;
-       chop;
+       s|\R$||;                # Better chomp
        @a=split;
        $num{$a[3]}++;
        }
index d726f2c..0bf1e48 100644 (file)
@@ -257,7 +257,7 @@ foreach (@out)
                                }
                        $out=$t;
                        }
-               chop $out;
+               chop $out;      # Get rid of the last comma
                print OUT "$out";
                }
        else
index ea2caf5..107647a 100644 (file)
@@ -5,7 +5,7 @@ $max_nid=0;
 $o=0;
 while(<NUMIN>)
        {
-       chop;
+       s|\R$||;
        $o++;
        s/#.*$//;
        next if /^\s*$/;
@@ -28,7 +28,7 @@ $Cname="";
 $o=0;
 while (<IN>)
        {
-       chop;
+       s|\R$||;
        $o++;
         if (/^!module\s+(.*)$/)
                {
index 05b987a..7ebd74c 100644 (file)
@@ -13,7 +13,7 @@ open(IN, $mac_file) || die "Can't open $mac_file, $!\n";
 
 while (<IN>)
        {
-       chomp;
+       s|\R$||;                # Better chomp
        my ($name, $num) = /^(\S+)\s+(\S+)$/;
        $oid_tbl{$name} = $num;
        }
@@ -25,7 +25,7 @@ my $ln = 1;
 
 while (<IN>)
        {
-       chomp;
+       s|\R$||;                # Better chomp
        s/#.*$//;
        next if (/^\S*$/);
        my ($xr, $p1, $p2) = /^(\S+)\s+(\S+)\s+(\S+)/;
@@ -112,6 +112,6 @@ sub check_oid
        my ($chk) = @_;
        if (!exists $oid_tbl{$chk})
                {
-               die "Can't find \"$chk\", $!\n";
+               die "Can't find \"$chk\"\n";
                }
        }
index 1f5bced..a0b3bc0 100755 (executable)
@@ -80,7 +80,7 @@ my $nasm=0;
 
 if    ($flavour eq "mingw64")  { $gas=1; $elf=0; $win64=1;
                                  $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`;
-                                 chomp($prefix);
+                                 $prefix =~ s|\R$||; # Better chomp
                                }
 elsif ($flavour eq "macosx")   { $gas=1; $elf=0; $prefix="_"; $decor="L\$"; }
 elsif ($flavour eq "masm")     { $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; }
@@ -852,7 +852,7 @@ ___
 }
 while($line=<>) {
 
-    chomp($line);
+    $line =~ s|\R$||;           # Better chomp
 
     $line =~ s|[#!].*$||;      # get rid of asm-style comments...
     $line =~ s|/\*.*\*/||;     # ... and C-style comments...
index 176b956..f7d3baa 100644 (file)
@@ -7,7 +7,7 @@ my $reldir = "";
 my $searchterm = "";
 my $goal = "";
 while (<$minfo>) {
-    chomp;
+    s|\R$||;
 
     if (/^RELATIVE_DIRECTORY=(.*)$/) {
         $reldir=$1;
index 35bd6ed..0f69335 100644 (file)
@@ -2,7 +2,7 @@
 
 $/ = "";                       # Eat a paragraph at once.
 while(<STDIN>) {
-    chop;
+    s|\R$||;
     s/\n/ /gm;
     if (/^=head1 /) {
        $name = 0;
index d5c78ba..d984196 100755 (executable)
@@ -13,7 +13,7 @@ while ($ARGV[0] =~ /^([^\s=]+)\s*=\s*(.*)$/)
 $s="";
 while (<>)
        {
-       chop;
+       s|\R$||;
        s/#.*//;
        if (/^([^\s=]+)\s*=\s*(.*)$/)
                {
@@ -23,10 +23,10 @@ while (<>)
                        {
                        if ($b =~ /\\$/)
                                {
-                               chop($b);
+                               $b=$`; # Keep what is before the backslash
                                $o.=$b." ";
                                $b=<>;
-                               chop($b);
+                               $b =~ s|\R$||; # Better chomp
                                }
                        else
                                {
@@ -43,7 +43,7 @@ while (<>)
                }
        }
 
-$pwd=`pwd`; chop($pwd);
+$pwd=`pwd`; $pwd =~ s|\R$||;
 
 if ($sym{'TOP'} eq ".")
        {
@@ -55,7 +55,7 @@ else  {
        @_=split(/\//,$pwd);
        $z=$#_-$n+1;
        foreach $i ($z .. $#_) { $dir.=$_[$i]."/"; }
-       chop($dir);
+       chop($dir);             # Remove the last slash
        }
 
 print "RELATIVE_DIRECTORY=$dir\n";
index 4a88fc6..7b16e04 100644 (file)
@@ -59,7 +59,7 @@ open my $sha1_res, '<', $fips_target.".sha1" or die "Get hash failure";
 $fips_hash=<$sha1_res>;
 close $sha1_res;
 unlink $fips_target.".sha1";
-chomp $fips_hash;
+$fips_hash =~ s|\R$||;          # Better chomp
 die "Get hash failure" if $? != 0;
 
 
@@ -97,8 +97,8 @@ sub check_hash
        $hashfile = <IN>;
        close IN;
        $hashval = `$sha1_exe ${fips_libdir}/$filename`;
-       chomp $hashfile;
-       chomp $hashval;
+       $hashfile =~ s|\R$||;    # Better chomp
+       $hashval =~ s|\R$||;     # Better chomp
        $hashfile =~ s/^.*=\s+//;
        $hashval =~ s/^.*=\s+//;
        die "Invalid hash syntax in file" if (length($hashfile) != 40);
index 4144130..3a9f0d7 100755 (executable)
@@ -553,7 +553,7 @@ if ($fips)
                        {
                        open (IN, "util/fipslib_path.txt") || fipslib_error();
                        $fipslibdir = <IN>;
-                       chomp $fipslibdir;
+                       $fipslibdir =~ s|\R$||;
                        close IN;
                        }
                fips_check_files($fipslibdir,
@@ -1159,7 +1159,7 @@ sub do_defs
                elsif ($var eq "SSLOBJ")
                        { $ret.="\$(OBJ_D)\\\$(SSL).res "; }
                }
-       chomp($ret);
+       chomp($ret);            # Does this actually do something? /RL
        $ret.="\n\n";
        return($ret);
        }
index aa85ec8..b5ebc18 100755 (executable)
@@ -459,7 +459,7 @@ sub do_defs
                        if($parens > 0) {
                                #Inside a DEPRECATEDIN
                                $stored_multiline .= $_;
-                               chomp $stored_multiline;
+                               $stored_multiline =~ s|\R$||; # Better chomp
                                print STDERR "DEBUG: Continuing multiline DEPRECATEDIN: $stored_multiline\n" if $debug;
                                $parens = count_parens($stored_multiline);
                                if ($parens == 0) {
@@ -480,9 +480,7 @@ sub do_defs
                        }
 
                        if (/\\$/) {
-                               chomp; # remove eol
-                               chop; # remove ending backslash
-                               $line = $_;
+                               $line = $`; # keep what was before the backslash
                                next;
                        }
 
@@ -499,7 +497,7 @@ sub do_defs
                                $cpp++ if /^#\s*if/;
                                $cpp-- if /^#\s*endif/;
                                next;
-                       }
+                       }
                        $cpp = 1 if /^#.*ifdef.*cplusplus/;
 
                        s/{[^{}]*}//gs;                      # ignore {} blocks
@@ -867,7 +865,7 @@ sub do_defs
                                                        \@current_algorithms);
                                        } else {
                                                $stored_multiline = $_;
-                                               chomp $stored_multiline;
+                                               $stored_multiline =~ s|\R$||;
                                                print STDERR "DEBUG: Found multiline DEPRECATEDIN starting with: $stored_multiline\n" if $debug;
                                                next;
                                        }
@@ -1365,7 +1363,7 @@ sub load_numbers
 
        open(IN,"<$name") || die "unable to open $name:$!\n";
        while (<IN>) {
-               chop;
+               s|\R$||;        # Better chomp
                s/#.*$//;
                next if /^\s*$/;
                @a=split;
index 13c9974..939a87c 100644 (file)
@@ -556,7 +556,7 @@ EOF
        if (open(IN,"<$cfile")) {
                my $line = "";
                while (<IN>) {
-                       chomp;
+                       s|\R$||; # Better chomp
                        $_ = $line . $_;
                        $line = "";
                        if (/{ERR_(FUNC|REASON)\(/) {
index d668316..4fbe29a 100755 (executable)
@@ -95,7 +95,7 @@ my $s="";
 
 while (<IN>)
        {
-       chop;
+       s|\R$||;
        s/#.*//;
        if (/^([^\s=]+)\s*=\s*(.*)$/)
                {
@@ -105,10 +105,10 @@ while (<IN>)
                        {
                        if ($b =~ /\\$/)
                                {
-                               chop($b);
+                               $b=$`;
                                $o.=$b." ";
                                $b=<IN>;
-                               chop($b);
+                               $b =~ s|\R$||;
                                }
                        else
                                {
index 59842ef..06d494a 100644 (file)
@@ -54,7 +54,7 @@ $cversion=`$cc -V |head -1` if $cversion =~ "Error";
 $cversion=`$cc --version` if $cversion eq "";
 $cversion =~ s/Reading specs.*\n//;
 $cversion =~ s/usage.*\n//;
-chomp $cversion;
+$cversion =~ s|\R$||;
 
 if (open(IN,"<CHANGES")) {
     while(<IN>) {
index 9d6c603..57e635b 100755 (executable)
@@ -54,7 +54,7 @@ sub loadfile
                $header=0 if /^[dr]sa/;
                if (/^type/) { $header=0; next; }
                next if $header;
-               chop;
+               s|\R$||;
                @a=split;
                if ($a[0] =~ /^[dr]sa$/)
                        {