[groff] 05/15: [gropdf]: Revise diagnostic message handling.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit e5e658231466036c793f61ddff9aff2a4f373a9e
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sat Jun 4 13:48:35 2022 -0500

    [gropdf]: Revise diagnostic message handling.
    
    * src/devices/gropdf/gropdf.pl: Revise diagnostic message handling.
    
      (top level): Add new scalar `progname` to house executable name.
    
      (Msg): Output messages in format recommended by GNU Coding Standards
      manual.  Identify who's talking (Savannah #52463).  Rename `lev`
      scalar to `fatal` since it is used only as a Boolean for immediately
      exiting with failure status.  Report diagnostic severity as part of
      message.
    
      (Warn, Die): Add new subroutines through which all diagnostics are now
      emitted.
    
      (top level): Migrate a use of Perl `die` builtin to our `Die`.
    
      (top level, ToPoints, LoadDownload, LoadDesc, do_x, GetPoints,
      LoadSWF, LoadPDF, LoadStream, BuildStream, ParsePDFHash, LoadFont,
      GetType1, GetChunk, RemapChr, do_N): Migrate `Msg(0, ...)` calls to
      `Warn` and `Msg(1, ...)` to `Die`.  Begin messages in lowercase (GNU
      Coding Standards).  Recast a few messages for clarity.
    
    Continues the long process of fixing Savannah #52463.
    
    Also update editor aid comment, wrap some long lines, and make
    indentation more consistent.
---
 ChangeLog                    |  22 ++++++++
 src/devices/gropdf/gropdf.pl | 125 +++++++++++++++++++++++++++----------------
 2 files changed, 101 insertions(+), 46 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a6357fdb..3b125d21 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,25 @@
+2022-06-04  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * src/devices/gropdf/gropdf.pl: Revise diagnostic message
+       handling.
+       (top level): Add new scalar `progname` to house executable name.
+       (Msg): Output messages in format recommended by GNU Coding
+       Standards manual.  Identify who's talking (Savannah #52463).
+       Rename `lev` scalar to `fatal` since it is used only as a
+       Boolean for immediately exiting with failure status.  Report
+       diagnostic severity as part of message.
+       (Warn, Die): Add new subroutines through which all diagnostics
+       are now emitted.
+       (top level): Migrate a use of Perl `die` builtin to our `Die`.
+       (top level, ToPoints, LoadDownload, LoadDesc, do_x, GetPoints,
+       LoadSWF, LoadPDF, LoadStream, BuildStream, ParsePDFHash,
+       LoadFont, GetType1, GetChunk, RemapChr, do_N): Migrate `Msg(0,
+       ...)` calls to `Warn` and `Msg(1, ...)` to `Die`.  Begin
+       messages in lowercase (GNU Coding Standards).  Recast a few
+       messages for clarity.
+
+       Continues the long process of fixing Savannah #52463.
+
 2022-06-04  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * src/devices/gropdf/gropdf.pl (Load_Config): Drop unused
diff --git a/src/devices/gropdf/gropdf.pl b/src/devices/gropdf/gropdf.pl
index 495d99e1..aef411e0 100644
--- a/src/devices/gropdf/gropdf.pl
+++ b/src/devices/gropdf/gropdf.pl
@@ -12,8 +12,8 @@
 # Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
-# groff is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# groff is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 # for more details.
 #
@@ -32,22 +32,25 @@ use constant
     USED               => 4,
 };
 
+(my $progname=$0) =~s @.*/@@;
+
 my $gotzlib=0;
 
 my $rc = eval
 {
-  require Compress::Zlib;
-  Compress::Zlib->import();
-  1;
+    require Compress::Zlib;
+    Compress::Zlib->import();
+    1;
 };
 
 if($rc)
 {
-  $gotzlib=1;
+    $gotzlib=1;
 }
 else
 {
-    Msg(0,"Perl module Compress::Zlib not available - cannot compress this 
pdf");
+    Warn("Perl module 'Compress::Zlib' not available; cannot compress"
+        . " this PDF");
 }
 
 my %cfg;
@@ -228,17 +231,18 @@ if (defined($unicodemap))
     elsif (-r $unicodemap)
     {
        local $/;
-       open(F,"<$unicodemap") or die "gropdf: Failed to open '$unicodemap'";
+       open(F,"<$unicodemap") or Die("failed to open '$unicodemap'");
        ($ucmap)=(<F>);
        close(F);
     }
     else
     {
-       Msg(0,"Failed to find '$unicodemap' - ignoring");
+       Warn("failed to find '$unicodemap'; ignoring");
     }
 }
 
-# Search for 'font directory': paths in -f opt, shell var GROFF_FONT_PATH, 
default paths
+# Search for 'font directory': paths in -f opt, shell var
+# GROFF_FONT_PATH, default paths
 
 my $fontdir=$cfg{GROFF_FONT_PATH};
 $fontdir=$ENV{GROFF_FONT_PATH}.$cfg{RT_SEP}.$fontdir if 
exists($ENV{GROFF_FONT_PATH});
@@ -603,7 +607,7 @@ sub ToPoints
     }
     else
     {
-       Msg(1,"Unknown scaling factor '$unit'");
+       Die("invalid scaling unit '$unit'");
     }
 }
 
@@ -639,7 +643,7 @@ sub LoadDownload
        close($f);
     }
 
-    Msg(1,"Failed to open 'download'") if !$found;
+    Die("failed to open 'download' file") if !$found;
 }
 
 sub OpenFile
@@ -666,7 +670,8 @@ sub LoadDesc
     my $f;
 
     OpenFile(\$f,$fontdir,"DESC");
-    Msg(1,"Failed to open 'DESC'") if !defined($f);
+    Die("failed to open device description file 'DESC'")
+       if !defined($f);
 
     while (<$f>)
     {
@@ -692,7 +697,8 @@ sub do_x
 
     if ($xcmd eq 'T')
     {
-       Msg(0,"Expecting a pdf pipe (got $xprm[0])") if $xprm[0] ne 
substr($devnm,3);
+       Warn("expecting a PDF pipe (got $xprm[0])")
+           if $xprm[0] ne substr($devnm,3);
     }
     elsif ($xcmd eq 'f')       # Register Font
     {
@@ -1038,7 +1044,7 @@ sub do_x
                    }
                    else
                    {
-                       Msg(0,"Unknown filetype '$fil'");
+                       Warn("unrecognized 'import' file type '$fil'");
                        return undef;
                    }
                }
@@ -1193,14 +1199,17 @@ sub do_x
                                            }
                                            else
                                            {
-                                               Msg(0,"Parameter must be 
top|bottom|before|after not '$ba'");
+                                               # XXX: identation wince
+                                               Warn(
+"expected 'switchtopage' parameter to be one of"
+. "'top|bottom|before|after', got '$ba'");
                                                last FIND;
                                            }
                                        }
 
                                    }
 
-                                   Msg(0,"Can't find page ref '$ref'");
+                                   Warn("cannot find page ref '$ref'");
                                    last FIND
 
                                }
@@ -1208,7 +1217,7 @@ sub do_x
                        }
                        else
                        {
-                           Msg(0,"Can't find page named '$want'");
+                           Warn("cannot find page named '$want'");
                        }
                    }
 
@@ -1417,10 +1426,12 @@ sub GetPoints
     return $val;
 }
 
-# Although the PDF reference mentions XObject/Form as a way of incorporating 
an external PDF page into
-# the current PDF, it seems not to work with any current PDF reader (although 
I am told (by Leonard Rosenthol,
-# who helped author the PDF ISO standard) that Acroread 9 does support it, 
empiorical observation shows otherwise!!).
-# So... do it the hard way - full PDF parser and merge required objects!!!
+# Although the PDF reference mentions XObject/Form as a way of
+# incorporating an external PDF page into the current PDF, it seems not
+# to work with any current PDF reader (although I am told (by Leonard
+# Rosenthol, who helped author the PDF ISO standard) that Acroread 9
+# does support it, empirical observation shows otherwise!!).  So... do
+# it the hard way - full PDF parser and merge required objects!!!
 
 # sub BuildRef
 # {
@@ -1432,7 +1443,7 @@ sub GetPoints
 #
 #      if (!open(PDF,"<$fil"))
 #      {
-#              Msg(0,"Failed to open '$fil'");
+#              Warn("failed to open '$fil'");
 #              return(undef);
 #      }
 #
@@ -1487,7 +1498,7 @@ sub LoadSWF
 
     if (!open(PDF,"<$fil"))
     {
-       Msg(0,"Failed to open '$fil'");
+       Warn("failed to open SWF '$fil'");
        return(undef);
     }
 
@@ -1588,7 +1599,7 @@ sub LoadPDF
 
     if (!defined($PD))
     {
-       Msg(0,"Failed to open PDF '$pdfnm'");
+       Warn("failed to open PDF '$pdfnm'");
        return undef;
     }
 
@@ -1639,7 +1650,7 @@ sub LoadPDF
            }
            else
            {
-               Msg(0,"Parsing PDF '$pdfnm' failed");
+               Warn("parsing PDF '$pdfnm' failed");
                return undef;
            }
        }
@@ -1781,10 +1792,12 @@ sub LoadStream
 
     $l=$pdf->[$$l]->{OBJ} if (defined($l) && ref($l) eq 'OBJREF');
 
-    Msg(1,"Unable to determine length of stream \@$o->{STREAMPOS}->[0]") if 
!defined($l);
+    Die("unable to determine length of stream \@$o->{STREAMPOS}->[0]")
+       if !defined($l);
 
     sysseek(PD,$o->{STREAMPOS}->[0],0);
-    Msg(0,'Failed to read all the stream') if $l != 
sysread(PD,$o->{STREAM},$l);
+    Warn("failed to read all of the stream")
+       if $l != sysread(PD,$o->{STREAM},$l);
 
     if ($gotzlib and exists($o->{OBJ}->{'Filter'}) and $o->{OBJ}->{'Filter'} 
eq '/FlateDecode')
     {
@@ -1812,7 +1825,7 @@ sub BuildStream
     }
     else
     {
-       Msg(0,"unexpected 'Contents'");
+       Warn("unexpected 'Contents'");
     }
 
     foreach my $o (@{$objs})
@@ -2012,7 +2025,7 @@ sub ParsePDFHash
 
        if ($w[0])
        {
-           Msg(0,"PDF Dict Key '$wd' does not start with '/'");
+           Warn("PDF Dict Key '$wd' does not start with '/'");
            exit 1;
        }
        else
@@ -2164,13 +2177,34 @@ sub ParsePDFArray
     return($rtn);
 }
 
+sub Warn
+{
+    Msg(0,(@_));
+}
+
+sub Die
+{
+    Msg(1,(@_));
+}
+
 sub Msg
 {
-    my ($lev,$msg)=@_;
+    my ($fatal,$msg)=@_;
 
+    print STDERR "$progname:";
     print STDERR "$env{SourceFile}: " if exists($env{SourceFile});
+
+    if ($fatal)
+    {
+       print STDERR "fatal error: ";
+    }
+    else
+    {
+       print STDERR "warning: ";
+    }
+
     print STDERR "$msg\n";
-    exit 1 if $lev;
+    exit 1 if $fatal;
 }
 
 sub PutXY
@@ -2303,7 +2337,7 @@ sub LoadFont
        OpenFile(\$f,$fontdir,$fontnm);
     }
 
-    Msg(1,"Failed to open font '$ofontnm'") if !defined($f);
+    Die("failed to open font '$ofontnm'") if !defined($f);
 
     my $foundry='';
     $foundry=$1 if $fontnm=~m/^(.*?)-/;
@@ -2397,7 +2431,8 @@ sub LoadFont
     {
        # Not a Base Font
        my ($l1,$l2,$l3,$t1stream)=GetType1($download{$fontkey});
-       Msg(0,"Incorrect font format for '$fontkey' ($l1)") if 
!defined($t1stream);
+       Warn("incorrect font format for '$fontkey' ($l1)")
+           if !defined($t1stream);
        $fno=++$objct;
        $fontlst{$fontno}->{OBJ}=BuildObj($objct,
                        {'Type' => '/Font',
@@ -2442,7 +2477,7 @@ sub LoadFont
     }
     else
     {
-       Msg(0, "unable to embed font file for '$fnt{internalname}'"
+       Warn("unable to embed font file for '$fnt{internalname}'"
            . " ($ofontnm) (corrupt 'download' file?)") if $embedall;
        $fno=++$objct;
        $fontlst{$fontno}->{OBJ}=BuildObj($objct,
@@ -2504,7 +2539,7 @@ sub GetType1
     my $f;
 
     OpenFile(\$f,$fontdir,"$file");
-    Msg(1,"Failed to open '$file'") if !defined($f);
+    Die("failed to open '$file'") if !defined($f);
 
     $head=GetChunk($f,1,"currentfile eexec");
     $body=GetChunk($f,2,"00000000") if !eof($f);
@@ -2551,15 +2586,11 @@ sub GetChunk
                return if $chunktype == 3;
 
                $ct=read($F,$hdr,4);
-
-               Msg(1,"Failed to read binary segment length"), return if $ct != 
4;
-
+               Die("failed to read binary segment length") if $ct != 4;
                my $sl=unpack('V',$hdr);
                my $data;
                my $chk=read($F,$data,$sl);
-
-               Msg(1 ,"Failed to read binary segment"), return if $chk != $sl;
-
+               Die("failed to read binary segment") if $chk != $sl;
                $chunk.=$data;
            }
            else
@@ -3414,7 +3445,7 @@ sub d3
     return(sprintf("%.3f",shift || 0));
 }
 
-sub  LoadAhead
+sub LoadAhead
 {
     my $no=shift;
 
@@ -3726,7 +3757,7 @@ sub RemapChr
     }
     else
     {
-       Msg(0,"Too many glyphs used in font '$cft'");
+       Warn("too many glyphs used in font '$cft'");
        return(32);
     }
 }
@@ -3748,7 +3779,7 @@ sub do_N
 
     if (!defined($fnt->{NO}->[$par]))
     {
-       Msg(0,"No chr($par) in font $fnt->{internalname}");
+       Warn("no chr($par) in font $fnt->{internalname}");
        return;
     }
 
@@ -3766,8 +3797,10 @@ sub do_n
     PutHotSpot($xpos) if defined($mark);
 }
 
-
 1;
+
 # Local Variables:
+# fill-column: 72
 # mode: CPerl
 # End:
+# vim: set cindent noexpandtab shiftwidth=4 softtabstop=4 textwidth=72: