dpkg-gensymbols: skip directories accessed through a symlink

* scripts/dpkg-gensymbols.pl: It was already skipping symlinks
within the package build tree. Now it also skips real
directories accessed through a symlink contained in the package
build tree. Package like libc6-386 had symlinks usr/lib32
pointing to some directories outside of the build tree and
the LD_LIBRARY_PATH set by fakeroot led contained
/usr/lib32/libfakeroot which made dpkg-gensymbols scan this
directory and add libfakeroot to the libc6-386 symbols file!

ChangeLog

@@ -1,3 +1,14 @@
+2008-08-29  Raphael Hertzog  <hertzog@debian.org>
+
+	* scripts/dpkg-gensymbols.pl: It was already skipping symlinks
+	within the package build tree. Now it also skips real
+	directories accessed through a symlink contained in the package
+	build tree. Package like libc6-386 had symlinks usr/lib32
+	pointing to some directories outside of the build tree and
+	the LD_LIBRARY_PATH set by fakeroot led contained
+	/usr/lib32/libfakeroot which made dpkg-gensymbols scan this
+	directory and add libfakeroot to the libc6-386 symbols file!
+
 2008-08-29  Raphael Hertzog  <hertzog@debian.org>
 
 	* scripts/Dpkg/Source/Package/V3/quilt.pm: run_quilt() can be run

debian/changelog

@@ -8,6 +8,10 @@ dpkg (1.14.22) UNRELEASED; urgency=low
   * Fix permissions of the automatically generated pacth in "2.0" and "3.0
     (quilt)" format. They were improperly set to 0600 due to tempfile()
     and were not reset to a sane value. Closes: #496925
+  * Fix dpkg-gensymbols to not scan (real) directories accessed through a
+    symlink contained in the build tree as they may well not be part of
+    the package (with absolute symlinks). It was already skipping symlinks
+    (since 1.14.16.6) for similar reasons.
 
   [ Updated dpkg translations ]
   * Brazilian Portuguese (Felipe Augusto van de Wiel).

scripts/dpkg-gensymbols.pl

@@ -12,6 +12,7 @@ use Dpkg::Gettext;
 use Dpkg::ErrorHandling qw(warning error syserr usageerr);
 use Dpkg::Control;
 use Dpkg::Changelog qw(parse_changelog);
+use Dpkg::Path qw(check_files_are_the_same);
 
 textdomain("dpkg-dev");
 
@@ -137,12 +138,18 @@ foreach my $file ($input, $output, "debian/$oppackage.symbols.$host_arch",
 
 # Scan package build dir looking for libraries
 if (not scalar @files) {
-    foreach my $path (@librarypaths) {
+    PATH: foreach my $path (@librarypaths) {
 	my $libdir = "$packagebuilddir$path";
 	$libdir =~ s{/+}{/}g;
 	lstat $libdir;
 	next if not -d _;
 	next if -l _; # Skip directories which are symlinks
+        # Skip any directory _below_ a symlink as well
+        my $updir = $libdir;
+        while (($updir =~ s{/[^/]*$}{}) and
+               not check_files_are_the_same($packagebuilddir, $updir)) {
+            next PATH if -l $updir;
+        }
 	opendir(DIR, "$libdir") ||
 	    syserr(_g("Can't read directory %s: %s"), $libdir, $!);
 	push @files, grep {