[FYI] {master} refactor: use modern semantics of 'open'

[Eric Blake]

> * lib/Automake/XFile.pm: Update comments and POD documentation to
> suggest a more idiomatic/modern usage.
> (open): Be more robust in detecting whether the created file handle
> is being opened for writing.
> * lib/Automake/FileUtils.pm (update_file, contents): Call the
> 'Automake::XFile' and 'File::IO' constructors with two arguments
> rather than one; this change obsoletes ...
> (open_quote): ... this subroutine, which has thus been removed.
> (@EXPORT): Drop '&open_quote'.
> 
> Signed-off-by: Stefano Lattarini <address@hidden>
> ---
>  lib/Automake/FileUtils.pm |   33 +++------------------------------
>  lib/Automake/XFile.pm     |   13 +++++++++----
>  2 files changed, 12 insertions(+), 34 deletions(-)
> 
>  Change tested with perl 5.10.1 and perl 5.6.0.  No regression in the
>  testsuite.  Patch already pushed to master.

Help!  I can't release autoconf 2.69 until I figure out how to work
around this patch.  After updating to the latest shared files, as well
as applying this patch, I'm now stuck with output going to a literal
file named '-' instead of going to stdout.  I suspect that the
conversion to the 2-arg form is mishandling our idiom of '-' as standard
in/out.

From 6ee479858ab4a4c4054d6ee334adae4e38295e52 Mon Sep 17 00:00:00 2001
From: Eric Blake <address@hidden>
Date: Tue, 24 Apr 2012 16:06:03 -0600
Subject: [PATCH] bin: replace older perl open_quote workaround with modern
 idiom

Now that we require more modern perl, we might as well use it.  See
https://lists.gnu.org/archive/html/automake-patches/2012-03/msg00111.html
for an example of how using 2-argument open makes life nicer.

* bin/autoheader.in: Use two-arg open, not open_quote.
* bin/autom4te.in: Likewise.
* bin/autoscan.in: Likewise.
* bin/autoupdate.in: Likewise.
* bin/ifnames.in: Likewise.

Signed-off-by: Eric Blake <address@hidden>
---
 bin/autoheader.in |   12 ++++++------
 bin/autom4te.in   |   17 +++++++++--------
 bin/autoscan.in   |   12 ++++++------
 bin/autoupdate.in |   16 ++++++++--------
 bin/ifnames.in    |    2 +-
 5 files changed, 30 insertions(+), 29 deletions(-)

diff --git a/bin/autoheader.in b/bin/autoheader.in
index d81a313..f51382f 100644
--- a/bin/autoheader.in
+++ b/bin/autoheader.in
@@ -201,7 +201,7 @@ $config_h_in ||= "$config_h.in";
 # only the name of the macro.
 %symbol = map { s/\(.*//; $_ => 1 } keys %symbol;

-my $out = new Autom4te::XFile ("> " . open_quote ("$tmp/config.hin"));
+my $out = new Autom4te::XFile "$tmp/config.hin", ">";

 # Don't write "do not edit" -- it will get copied into the
 # config.h, which it's ok to edit.
@@ -210,7 +210,7 @@ print $out "/* $config_h_in.  Generated from
$ARGV[0] by autoheader.  */\n";
 # Dump the top.
 if ($config_h_top)
   {
-    my $in = new Autom4te::XFile ("< " . open_quote ($config_h_top));
+    my $in = new Autom4te::XFile $config_h_top, "<";
     while ($_ = $in->getline)
       {
        print $out $_;
@@ -220,7 +220,7 @@ if ($config_h_top)
 # Dump `acconfig.h', except for its bottom portion.
 if ($acconfig_h)
   {
-    my $in = new Autom4te::XFile ("< " . open_quote ($acconfig_h));
+    my $in = new Autom4te::XFile $acconfig_h, "<";
     while ($_ = $in->getline)
       {
        last if /address@hidden@/;
@@ -238,7 +238,7 @@ foreach (sort keys %verbatim)
 # Dump bottom portion of `acconfig.h'.
 if ($acconfig_h)
   {
-    my $in = new Autom4te::XFile ("< " . open_quote ($acconfig_h));
+    my $in = new Autom4te::XFile $acconfig_h, "<";
     my $dump = 0;
     while ($_ = $in->getline)
       {
@@ -250,7 +250,7 @@ if ($acconfig_h)
 # Dump the bottom.
 if ($config_h_bot)
   {
-    my $in = new Autom4te::XFile ("< " . open_quote ($config_h_bot));
+    my $in = new Autom4te::XFile $config_h_bot, "<";
     while ($_ = $in->getline)
       {
        print $out $_;
@@ -261,7 +261,7 @@ $out->close;

 # Check that all the symbols have a template.
 {
-  my $in = new Autom4te::XFile ("< " . open_quote ("$tmp/config.hin"));
+  my $in = new Autom4te::XFile "$tmp/config.hin", "<";
   my $suggest_ac_define = 1;
   while ($_ = $in->getline)
     {
diff --git a/bin/autom4te.in b/bin/autom4te.in
index 11773c9..c2424c9 100644
--- a/bin/autom4te.in
+++ b/bin/autom4te.in
@@ -258,7 +258,7 @@ sub load_configuration ($)
   my ($file) = @_;
   use Text::ParseWords;

-  my $cfg = new Autom4te::XFile ("< " . open_quote ($file));
+  my $cfg = new Autom4te::XFile $file, "<";
   my $lang;
   while ($_ = $cfg->getline)
     {
@@ -527,7 +527,8 @@ sub handle_output ($$)
   handle_traces ($req, "$tmp/patterns",
                 ('m4_pattern_forbid' => 'forbid:$1:$2',
                  'm4_pattern_allow'  => 'allow:$1'));
-  my @patterns = new Autom4te::XFile ("< " . open_quote
("$tmp/patterns"))->getlines;
+  my $pattern_file = new Autom4te::XFile "$tmp/patterns", "<";
+  my @patterns = $pattern_file->getlines;
   chomp @patterns;
   my %forbidden =
     map { /^forbid:([^:]+):.+$/ => /^forbid:[^:]+:(.+)$/ } @patterns;
@@ -554,7 +555,7 @@ sub handle_output ($$)
     }
   fatal "cannot create $output: $!"
     unless $out;
-  my $in = new Autom4te::XFile ("< " . open_quote ($ocache . $req->id));
+  my $in = new Autom4te::XFile $ocache . $req->id, "<";

   my %prohibited;
   my $res;
@@ -599,7 +600,7 @@ sub handle_output ($$)
   if ($ARGV[$#ARGV] ne '-')
     {
       my $prohibited = '\b(' . join ('|', keys %prohibited) . ')\b';
-      my $file = new Autom4te::XFile ("< " . open_quote ($ARGV[$#ARGV]));
+      my $file = new Autom4te::XFile $ARGV[$#ARGV], "<";

       while ($_ = $file->getline)
        {
@@ -717,7 +718,7 @@ sub handle_traces ($$%)
   verb "formatting traces for `$output': " . join (', ', sort keys %trace);

   # Processing the traces.
-  my $trace_m4 = new Autom4te::XFile ("> " . open_quote
("$tmp/traces.m4"));
+  my $trace_m4 = new Autom4te::XFile "$tmp/traces.m4", ">";

   $_ = <<'EOF';
   divert(-1)
@@ -818,7 +819,7 @@ EOF
   #
   # Pay attention that the file name might include colons, if under DOS
   # for instance, so we don't use `[^:]+'.
-  my $traces = new Autom4te::XFile ("< " . open_quote ($tcache .
$req->id));
+  my $traces = new Autom4te::XFile $tcache . $req->id, "<";
   while ($_ = $traces->getline)
     {
       # Trace with arguments, as the example above.  We don't try
@@ -834,7 +835,7 @@ EOF
   $trace_m4->close;

   my $in = new Autom4te::XFile ("$m4 " . shell_quote ("$tmp/traces.m4")
. " |");
-  my $out = new Autom4te::XFile ("> " . open_quote ($output));
+  my $out = new Autom4te::XFile $output, ">";

   # This is dubious: should we really transform the quadrigraphs in
   # traces?  It might break balanced [ ] etc. in the output.  The
@@ -896,7 +897,7 @@ sub up_to_date ($)
   handle_traces ($req, "$tmp/dependencies",
                 ('include'    => '$1',
                  'm4_include' => '$1'));
-  my $deps = new Autom4te::XFile ("< " . open_quote ("$tmp/dependencies"));
+  my $deps = new Autom4te::XFile "$tmp/dependencies", "<";
   while ($_ = $deps->getline)
     {
       chomp;
diff --git a/bin/autoscan.in b/bin/autoscan.in
index a67c48d..8aad720 100644
--- a/bin/autoscan.in
+++ b/bin/autoscan.in
@@ -169,7 +169,7 @@ sub init_tables ()
   # instead of duplicating the code in lots of configure.ac files.
   my $file = find_file ("autoscan/autoscan.list",
                        reverse (@prepend_include), @include);
-  my $table = new Autom4te::XFile "< " . open_quote ($file);
+  my $table = new Autom4te::XFile $file, "<";
   my $tables_are_consistent = 1;

   while ($_ = $table->getline)
@@ -244,7 +244,7 @@ sub scan_c_file ($)
   # Nonzero if in a multiline comment.
   my $in_comment = 0;

-  my $file = new Autom4te::XFile "< " . open_quote ($file_name);
+  my $file = new Autom4te::XFile $file_name, "<";

   while ($_ = $file->getline)
     {
@@ -310,7 +310,7 @@ sub scan_makefile ($)
   my ($file_name) = @_;
   push @makefiles, $File::Find::name;

-  my $file = new Autom4te::XFile "< " . open_quote ($file_name);
+  my $file = new Autom4te::XFile $file_name, "<";

   while ($_ = $file->getline)
     {
@@ -352,7 +352,7 @@ sub scan_sh_file ($)
   my ($file_name) = @_;
   push @shfiles, $File::Find::name;

-  my $file = new Autom4te::XFile "< " . open_quote ($file_name);
+  my $file = new Autom4te::XFile $file_name, "<";

   while ($_ = $file->getline)
     {
@@ -521,7 +521,7 @@ sub output ($)
   my $configure_scan = shift;
   my %unique_makefiles;

-  my $file = new Autom4te::XFile "> " . open_quote ($configure_scan);
+  my $file = new Autom4te::XFile $configure_scan, ">";

   print $file
     ("#                                               -*- Autoconf -*-\n" .
@@ -639,7 +639,7 @@ sub check_configure_ac ($)
 ## -------------- ##

 parse_args;
-$log = new Autom4te::XFile "> " . open_quote ("$me.log");
+$log = new Autom4te::XFile "$me.log", ">";

 $autoconf .= " --debug" if $debug;
 $autoconf .= " --verbose" if $verbose;
diff --git a/bin/autoupdate.in b/bin/autoupdate.in
index 9737d49..ff56759 100644
--- a/bin/autoupdate.in
+++ b/bin/autoupdate.in
@@ -130,7 +130,7 @@ sub handle_autoconf_macros ()
 {
   # Get the builtins.
   xsystem ("echo dumpdef | $m4 2>" . shell_quote ("$tmp/m4.defs") . "
>/dev/null");
-  my $m4_defs = new Autom4te::XFile "< " . open_quote ("$tmp/m4.defs");
+  my $m4_defs = new Autom4te::XFile "$tmp/m4.defs", "<";
   while ($_ = $m4_defs->getline)
     {
       $m4_builtins{$1} = 1
@@ -186,9 +186,9 @@ sub handle_autoconf_macros ()

   # ac.m4 -- autoquoting definitions of the AC macros (M4sugar excluded).
   # unac.m4 -- undefine the AC macros.
-  my $ac_m4 = new Autom4te::XFile "> " . open_quote ("$tmp/ac.m4");
+  my $ac_m4 = new Autom4te::XFile "$tmp/ac.m4", ">";
   print $ac_m4 "# ac.m4 -- autoquoting definitions of the AC macros.\n";
-  my $unac_m4 = new Autom4te::XFile "> " . open_quote ("$tmp/unac.m4");
+  my $unac_m4 = new Autom4te::XFile "$tmp/unac.m4", ">";
   print $unac_m4 "# unac.m4 -- undefine the AC macros.\n";
   foreach (sort keys %ac_macros)
     {
@@ -199,11 +199,11 @@ sub handle_autoconf_macros ()
   # m4save.m4 -- save the m4 builtins.
   # unm4.m4 -- disable the m4 builtins.
   # m4.m4 -- enable the m4 builtins.
-  my $m4save_m4 = new Autom4te::XFile "> " . open_quote ("$tmp/m4save.m4");
+  my $m4save_m4 = new Autom4te::XFile "$tmp/m4save.m4", ">";
   print $m4save_m4 "# m4save.m4 -- save the m4 builtins.\n";
-  my $unm4_m4 = new Autom4te::XFile "> " . open_quote ("$tmp/unm4.m4");
+  my $unm4_m4 = new Autom4te::XFile "$tmp/unm4.m4", ">";
   print $unm4_m4 "# unm4.m4 -- disable the m4 builtins.\n";
-  my $m4_m4 = new Autom4te::XFile "> " . open_quote ("$tmp/m4.m4");
+  my $m4_m4 = new Autom4te::XFile "$tmp/m4.m4", ">";
   print $m4_m4 "# m4.m4 -- enable the m4 builtins.\n";
   foreach (sort keys %m4_builtins)
     {
@@ -381,9 +381,9 @@ EOF
     $input_m4 =~ s/\$file/$file/g;

     # prepared input -- input, but reenables the quote before each AU
macro.
-    open INPUT_M4, "> " . open_quote ("$tmp/input.m4")
+    open INPUT_M4, "$tmp/input.m4", ">"
        or error "cannot open: $!";
-    open FILE, "< " . open_quote ($file)
+    open FILE, $file, "<"
        or error "cannot open: $!";
     print INPUT_M4 "$input_m4";
     while (<FILE>)
diff --git a/bin/ifnames.in b/bin/ifnames.in
index ba2cd05..51cec64 100644
--- a/bin/ifnames.in
+++ b/bin/ifnames.in
@@ -96,7 +96,7 @@ my %occurrence;
 sub scan_file ($)
 {
   my ($file_name) = @_;
-  my $file = new Autom4te::XFile ("< " . open_quote ($file_name));
+  my $file = new Autom4te::XFile $file_name, "<";
   while ($_ = $file->getline)
     {
       # Continuation lines.
-- 
1.7.7.6


-- 
Eric Blake   address@hidden    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature