Bug#485012: dpkg: dpkg-divert should provide option to determine which package diverts a file

[Timothy G Abbott]

Package: dpkg
Version: 1.14.18
Tags: patch
Severity: wishlist
dpkg-divert should provide an option to find out what package diverts a 
given file (currently the only way to extract this information is to parse 
the dpkg-divert output, which is not ideal).

I've attached a patch against current git to add this functionality.

        -Tim Abbottdiff --git a/man/dpkg-divert.8 b/man/dpkg-divert.8
index 2e9662f..00f312b 100644
--- a/man/dpkg-divert.8
+++ b/man/dpkg-divert.8
@@ -32,6 +32,10 @@ Remove a diversion for \fIfile\fP.
 .BI \-\-list " glob-pattern"
 List diversions matching \fIglob-pattern\fP.
 .TP
+.BI \-\-listpackage " file"
+Print the name of the package the diverts \fIfile\fP.  Prints LOCAL if
+\fIfile\fP is locally diverted and nothing if \fIfile\fP is not diverted.
+.TP
 .BI \-\-truename " file"
 Print the real name for a diverted file.
 .
diff --git a/scripts/dpkg-divert.pl b/scripts/dpkg-divert.pl
index 8c13cb8..03ee7af 100755
--- a/scripts/dpkg-divert.pl
+++ b/scripts/dpkg-divert.pl
@@ -30,6 +30,7 @@ Commands:
   [--add] <file>           add a diversion.
   --remove <file>          remove the diversion.
   --list [<glob-pattern>]  show file diversions.
+  --listpackage <file>     show what package diverts the file.
   --truename <file>        return the diverted file.
 
 Options:
@@ -98,6 +99,9 @@ while (@ARGV) {
     } elsif (m/^--list$/) {
         &checkmanymodes;
         $mode= 'list';
+    } elsif (m/^--listpackage$/) {
+        &checkmanymodes;
+        $mode= 'listpackage';
     } elsif (m/^--truename$/) {
         &checkmanymodes;
         $mode= 'truename';
@@ -210,6 +214,21 @@ if ($mode eq 'add') {
     }
     print $file, "\n";
     exit(0);
+} elsif ($mode eq 'listpackage') {
+    @ARGV == 1 || &badusage(sprintf(_g("--%s needs a single argument"), "truename"));
+    $file= $ARGV[0];
+    for (my $i = 0; $i <= $#contest; $i++) {
+	next unless $file eq $contest[$i];
+	if ($package[$i] eq ':') {
+	    # indicate package is local using something not in package namespace
+	    print "LOCAL\n";
+	} else {
+	    print $package[$i], "\n";
+	}
+	exit(0);
+    }
+    # print nothing if file is not diverted
+    exit(0);
 } else {
     &quit(sprintf(_g("internal error - bad mode \`%s'"), $mode));
 }