Knock off another to-do item: "Don't slurp the entire cvsps output

into memory (!)."

diff --git a/IkiWiki/Plugin/cvs.pm b/IkiWiki/Plugin/cvs.pm
index ccd9527cd799039618242742a19270557facfbb2..c1b40bda1099957b5c343d05bcec37fefb75d57b 100644 (file)
--- a/IkiWiki/Plugin/cvs.pm
+++ b/IkiWiki/Plugin/cvs.pm
@@ -278,12 +278,26 @@ sub rcs_recentchanges($) {
 
        chdir $config{srcdir} || error("Cannot chdir to $config{srcdir}: $!");
 
-       # there's no option to get the last N changesets, so read backwards
-       open CVSPS, "env TZ=UTC cvsps -q --cvs-direct -z 30 -x |" || error "couldn't get cvsps output: $!\n";
-       my @spsvc = reverse <CVSPS>;            # is this great? no it is not
-       close CVSPS || error "couldn't close cvsps output: $!\n";
+       # There's no cvsps option to get the last N changesets.
+       # Write full output to a temp file and read backwards.
 
-       while (my $line = shift @spsvc) {
+       eval q{use File::Temp qw/tempfile/};
+       error($@) if $@;
+       eval q{use File::ReadBackwards};
+       error($@) if $@;
+
+       my (undef, $tmpfile) = tempfile(OPEN=>0);
+       system("env TZ=UTC cvsps -q --cvs-direct -z 30 -x >$tmpfile");
+       if ($? == -1) {
+               error "couldn't run cvsps: $!\n";
+       } elsif (($? >>8) != 0) {
+               error "cvsps exited " . ($? >> 8) . ": $!\n";
+       }
+
+       tie(*SPSVC, 'File::ReadBackwards', $tmpfile)
+               || error "couldn't open $tmpfile for read: $!\n";
+
+       while (my $line = <SPSVC>) {
                $line =~ /^$/ || error "expected blank line, got $line";
 
                my ($rev, $user, $committype, $when);
@@ -303,7 +317,7 @@ sub rcs_recentchanges($) {
                #       @pages (and revisions)
                #
 
-               while ($line = shift @spsvc) {
+               while ($line = <SPSVC>) {
                        last if ($line =~ /^Members:/);
                        for ($line) {
                                s/^\s+//;
@@ -323,7 +337,7 @@ sub rcs_recentchanges($) {
                        } if length $page;
                }
 
-               while ($line = shift @spsvc) {
+               while ($line = <SPSVC>) {
                        last if ($line =~ /^Log:$/);
                        chomp $line;
                        unshift @message, { line => $line };
@@ -337,31 +351,31 @@ sub rcs_recentchanges($) {
                        $committype="cvs";
                }
 
-               $line = shift @spsvc;   # Tag
-               $line = shift @spsvc;   # Branch
+               $line = <SPSVC>;        # Tag
+               $line = <SPSVC>;        # Branch
 
-               $line = shift @spsvc;
+               $line = <SPSVC>;
                if ($line =~ /^Author: (.*)$/) {
                        $user = $1 unless defined $user && length $user;
                } else {
                        error "expected Author, got $line";
                }
 
-               $line = shift @spsvc;
+               $line = <SPSVC>;
                if ($line =~ /^Date: (.*)$/) {
                        $when = str2time($1, 'UTC');
                } else {
                        error "expected Date, got $line";
                }
 
-               $line = shift @spsvc;
+               $line = <SPSVC>;
                if ($line =~ /^PatchSet (.*)$/) {
                        $rev = $1;
                } else {
                        error "expected PatchSet, got $line";
                }
 
-               $line = shift @spsvc;   # ---------------------
+               $line = <SPSVC>;        # ---------------------
 
                push @ret, {
                        rev => $rev,
@@ -371,9 +385,11 @@ sub rcs_recentchanges($) {
                        message => [@message],
                        pages => [@pages],
                } if @pages;
-               return @ret if @ret >= $num;
+               last if @ret >= $num;
        }
 
+       unlink($tmpfile) || error "couldn't unlink $tmpfile: $!\n";
+
        return @ret;
 }