Let apt decide unpack order instead of sorting filenames

Now that the deb files can reside in different places sorting them leads
to subtil differences in the order and hence the created chroot. apts
unpack order on the other hand might not be a good order (but why would
one sorted from a to z be one?), but it is far more stable as it is
independent on the filenames.

coverage.sh

@@ -89,13 +89,6 @@ if [ ! -e shared/tarfilter ] || [ tarfilter -nt shared/tarfilter ]; then
 		cp -a /usr/bin/mmtarfilter shared/tarfilter
 	fi
 fi
-if [ ! -e shared/proxysolver ] || [ proxysolver -nt shared/proxysolver ]; then
-	if [ -e ./proxysolver ]; then
-		cp -a proxysolver shared
-	else
-		cp -a /usr/lib/apt/solvers/mmdebstrap-dump-solution shared/proxysolver
-	fi
-fi
 if [ ! -e shared/ldconfig.fakechroot ] || [ ldconfig.fakechroot -nt shared/ldconfig.fakechroot ]; then
 	if [ -e ./ldconfig.fakechroot ]; then
 		cp -a ldconfig.fakechroot shared
@@ -1533,7 +1526,7 @@ else
 	skipped=$((skipped+1))
 fi
 
-print_header "mode=$defaultmode,variant=apt: fail with file:// mirror"
+print_header "mode=$defaultmode,variant=apt: file:// mirror"
 cat << END > shared/test.sh
 #!/bin/sh
 set -eu
@@ -1542,13 +1535,9 @@ if [ ! -e /mmdebstrap-testenv ]; then
 	echo "this test requires the cache directory to be mounted on /mnt and should only be run inside a container" >&2
 	exit 1
 fi
-ret=0
-$CMD --mode=$defaultmode --variant=apt $DEFAULT_DIST /tmp/debian-chroot.tar "deb file:///mnt/cache/debian unstable main" || ret=\$?
+$CMD --mode=$defaultmode --variant=apt $DEFAULT_DIST /tmp/debian-chroot.tar "deb file:///mnt/cache/debian $DEFAULT_DIST main"
+tar -tf /tmp/debian-chroot.tar | sort | diff -u tar1.txt -
 rm /tmp/debian-chroot.tar
-if [ "\$ret" = 0 ]; then
-	echo expected failure but got exit \$ret >&2
-	exit 1
-fi
 END
 if [ "$HAVE_QEMU" = "yes" ]; then
 	./run_qemu.sh
@@ -3079,7 +3068,7 @@ $CMD \$include --mode=$defaultmode --variant=$variant \
 	--setup-hook='sync-in "'"\$tmpdir"'" /var/cache/apt/archives/partial' \
 	$DEFAULT_DIST - $mirror > test1.tar
 cmp orig.tar test1.tar
-$CMD \$include --mode=$defaultmode --variant=$variant --skip=download/empty \
+$CMD \$include --mode=$defaultmode --variant=$variant \
 	--customize-hook='touch "\$1"/var/cache/apt/archives/partial' \
 	--setup-hook='mkdir -p "\$1"/var/cache/apt/archives/' \
 	--setup-hook='sync-in "'"\$tmpdir"'" /var/cache/apt/archives/' \
@@ -3760,4 +3749,4 @@ if [ "$((skipped+runtests))" -ne "$total" ]; then
 	exit 1
 fi
 
-rm shared/test.sh shared/tar1.txt shared/tar2.txt shared/pkglist.txt shared/doc-debian.tar.list shared/mmdebstrap shared/taridshift shared/tarfilter shared/proxysolver
+rm shared/test.sh shared/tar1.txt shared/tar2.txt shared/pkglist.txt shared/doc-debian.tar.list shared/mmdebstrap shared/taridshift shared/tarfilter

mmdebstrap

@@ -872,30 +872,11 @@ sub run_dpkg_progress {
 }
 
 sub run_apt_progress {
-    my $options = shift;
-    my @debs    = @{ $options->{PKGS} // [] };
-    my $tmpedsp;
-    if (exists $options->{EDSP_RES}) {
-        (undef, $tmpedsp) = tempfile(
-            "mmdebstrap.edsp.XXXXXXXXXXXX",
-            OPEN   => 0,
-            TMPDIR => 1
-        );
-    }
+    my $options  = shift;
+    my @debs     = @{ $options->{PKGS} // [] };
     my $get_exec = sub {
         my @prefix = ();
         my @opts   = ();
-        if (exists $options->{EDSP_RES}) {
-            push @prefix, 'env', "APT_EDSP_DUMP_FILENAME=$tmpedsp";
-            if (-e "./proxysolver") {
-                # for development purposes, use the current directory if it
-                # contains a file called proxysolver
-                push @opts, ("-oDir::Bin::solvers=" . getcwd()),
-                  '--solver=proxysolver';
-            } else {
-                push @opts, '--solver=mmdebstrap-dump-solution';
-            }
-        }
         return (
             @prefix,
             @{ $options->{ARGV} },
@@ -950,38 +931,46 @@ sub run_apt_progress {
         }
     };
     run_progress $get_exec, $line_handler, $line_has_error, $options->{CHDIR};
-    if (exists $options->{EDSP_RES}) {
-        info "parsing EDSP results...";
-        open my $fh, '<', $tmpedsp
-          or error "failed to open $tmpedsp for reading: $!";
-        my $inst = 0;
-        my $pkg;
-        my $ver;
-        while (my $line = <$fh>) {
-            chomp $line;
-            if ($line ne "") {
-                if ($line =~ /^Install: \d+/) {
-                    $inst = 1;
-                } elsif ($line =~ /^Package: (.*)/) {
-                    $pkg = $1;
-                } elsif ($line =~ /^Version: (.*)/) {
-                    $ver = $1;
-                }
-                next;
-            }
-            if ($inst == 1 && defined $pkg && defined $ver) {
-                push @{ $options->{EDSP_RES} }, [$pkg, $ver];
-            }
-            $inst = 0;
-            undef $pkg;
-            undef $ver;
-        }
-        close $fh;
-        unlink $tmpedsp;
-    }
     return;
 }
 
+sub run_apt_download_progress {
+    my $options = shift;
+    my $tmplistofdebs;
+    if ($options->{dryrun}) {
+        info "simulate downloading packages with apt...";
+    } else {
+        info "downloading packages with apt...";
+        (undef, $tmplistofdebs) = tempfile(
+            "mmdebstrap.listofdebs.XXXXXXXXXXXX",
+            OPEN   => 0,
+            TMPDIR => 1
+        );
+    }
+    run_apt_progress({
+            ARGV => [
+                'apt-get',
+                '--yes',
+                '-oDebug::pkgDpkgPm=1',
+                '-oDir::Log=/dev/null',
+                $options->{dryrun}
+                ? '-oAPT::Get::Simulate=true'
+                : "-oDpkg::Pre-Install-Pkgs::=cat > $tmplistofdebs",
+                @{ $options->{APT_ARGV} },
+            ],
+        });
+    if ($tmplistofdebs) {
+        open my $fh, '<', $tmplistofdebs
+          or error "failed to open $tmplistofdebs for reading: $!";
+        my @listofdebs = <$fh>;
+        close $fh;
+        unlink $tmplistofdebs;
+        chomp(@listofdebs);
+        return @listofdebs;
+    }
+    return [];
+}
+
 sub run_chroot {
     my $cmd     = shift;
     my $options = shift;
@@ -2034,26 +2023,14 @@ sub run_update() {
 sub run_download() {
     my $options = shift;
 
-    # We use /var/cache/apt/archives/ to figure out which packages apt chooses
-    # to install. That's why the directory must be empty if:
-    #  - /var/cache/apt/archives exists, and
-    #  - no simulation run is done, and
-    #  - the variant is not extract or custom or the number to be
-    #    installed packages not zero
-    #
-    # We could also unconditionally use the proxysolver and then "apt-get
-    # download" any missing packages but using the proxysolver requires
-    # /usr/lib/apt/solvers/apt from the apt-utils package and we want to avoid
-    # that dependency.
-    #
     # In the future we want to replace downloading packages with "apt-get
-    # install --download-only" and installing them with dpkg by just installing
-    # the essential packages with apt from the outside with
-    # DPkg::Chroot-Directory. We are not doing that because then the preinst
-    # script of base-passwd will not be called early enough and packages will
-    # fail to install because they are missing /etc/passwd.
+    # install" and installing them with dpkg by just installing the essential
+    # packages with apt from the outside with DPkg::Chroot-Directory.
+    # We are not doing that because then the preinst script of base-passwd will
+    # not be called early enough and packages will fail to install because they
+    # are missing /etc/passwd.
     my @cached_debs = ();
-    my @dl_debs     = ();
+    my @dl_debs;
     if (
         !$options->{dryrun}
         && ((none { $_ eq $options->{variant} } ('extract', 'custom'))
@@ -2073,14 +2050,6 @@ sub run_download() {
             push @cached_debs, $deb;
         }
         closedir $dh;
-        if (scalar @cached_debs > 0) {
-            if (any { $_ eq 'download/empty' } @{ $options->{skip} }) {
-                info "skipping download/empty as requested";
-            } else {
-                error("/var/cache/apt/archives/ inside the chroot contains: "
-                      . (join ', ', (sort @cached_debs)));
-            }
-        }
     }
 
     # To figure out the right package set for the apt variant we can use:
@@ -2094,7 +2063,7 @@ sub run_download() {
             info "nothing to download -- skipping...";
             return ([], []);
         }
-        my %pkgs_to_install;
+        my @apt_argv = ['install'];
         for my $incl (@{ $options->{include} }) {
             for my $pkg (split /[,\s]+/, $incl) {
                 # strip leading and trailing whitespace
@@ -2103,32 +2072,15 @@ sub run_download() {
                 if ($pkg eq '') {
                     next;
                 }
-                $pkgs_to_install{$pkg} = ();
+                push @apt_argv, $pkg;
             }
         }
 
-        my %result = ();
-        if ($options->{dryrun}) {
-            info "simulate downloading packages with apt...";
-        } else {
-            # if there are already packages in /var/cache/apt/archives/, we
-            # need to use our proxysolver to obtain the solution chosen by apt
-            if (scalar @cached_debs > 0) {
-                $result{EDSP_RES} = \@dl_debs;
-            }
-            info "downloading packages with apt...";
-        }
-        run_apt_progress({
-                ARGV => [
-                    'apt-get',
-                    '--yes',
-                    '-oApt::Get::Download-Only=true',
-                    $options->{dryrun} ? '-oAPT::Get::Simulate=true' : (),
-                    'install'
-                ],
-                PKGS => [keys %pkgs_to_install],
-                %result
-            });
+        @dl_debs = run_apt_download_progress({
+                APT_ARGV => @apt_argv,
+                dryrun   => $options->{dryrun},
+            },
+        );
     } elsif ($options->{variant} eq 'apt') {
         # if we just want to install Essential:yes packages, apt and their
         # dependencies then we can make use of libapt treating apt as
@@ -2143,27 +2095,11 @@ sub run_download() {
         #                  remind me in 5+ years that I said that after I wrote
         #                  in the bugreport: "Are you crazy?!? Nobody in his
         #                  right mind would even suggest depending on it!")
-        my %result = ();
-        if ($options->{dryrun}) {
-            info "simulate downloading packages with apt...";
-        } else {
-            # if there are already packages in /var/cache/apt/archives/, we
-            # need to use our proxysolver to obtain the solution chosen by apt
-            if (scalar @cached_debs > 0) {
-                $result{EDSP_RES} = \@dl_debs;
-            }
-            info "downloading packages with apt...";
-        }
-        run_apt_progress({
-                ARGV => [
-                    'apt-get',
-                    '--yes',
-                    '-oApt::Get::Download-Only=true',
-                    $options->{dryrun} ? '-oAPT::Get::Simulate=true' : (),
-                    'dist-upgrade'
-                ],
-                %result
-            });
+        @dl_debs = run_apt_download_progress({
+                APT_ARGV => ['dist-upgrade'],
+                dryrun   => $options->{dryrun},
+            },
+        );
     } elsif (
         any { $_ eq $options->{variant} }
         ('essential', 'standard', 'important', 'required', 'buildd')
@@ -2172,23 +2108,8 @@ sub run_download() {
         # 17:27 < DonKult> (?essential includes 'apt' through)
         # 17:30 < josch> DonKult: no, because pkgCacheGen::ForceEssential ",";
         # 17:32 < DonKult> touché
-        my %result = ();
-        if ($options->{dryrun}) {
-            info "simulate downloading packages with apt...";
-        } else {
-            # if there are already packages in /var/cache/apt/archives/, we
-            # need to use our proxysolver to obtain the solution chosen by apt
-            if (scalar @cached_debs > 0) {
-                $result{EDSP_RES} = \@dl_debs;
-            }
-            info "downloading packages with apt...";
-        }
-        run_apt_progress({
-                ARGV => [
-                    'apt-get',
-                    '--yes',
-                    '-oApt::Get::Download-Only=true',
-                    $options->{dryrun} ? '-oAPT::Get::Simulate=true' : (),
+        @dl_debs = run_apt_download_progress({
+                APT_ARGV => [
                     'install',
                     '?narrow('
                       . (
@@ -2203,76 +2124,31 @@ sub run_download() {
                       . $options->{nativearch}
                       . '),?essential)'
                 ],
-                %result
-            });
+                dryrun => $options->{dryrun},
+            },
+        );
     } else {
         error "unknown variant: $options->{variant}";
     }
 
     my @essential_pkgs;
-    if (scalar @cached_debs > 0 && scalar @dl_debs > 0) {
-        my $archives = "/var/cache/apt/archives/";
-        # for each package in @dl_debs, check if it's in
-        # /var/cache/apt/archives/ and add it to @essential_pkgs
-        foreach my $p (@dl_debs) {
-            my ($pkg, $ver_epoch) = @{$p};
-            # apt appends the architecture at the end of the package name
-            ($pkg, my $arch) = split ':', $pkg, 2;
-            # apt replaces the colon by its percent encoding %3a
-            my $ver = $ver_epoch;
-            $ver =~ s/:/%3a/;
-            # the architecture returned by apt is the native architecture.
-            # Since we don't know whether the package is architecture
-            # independent or not, we first try with the native arch and then
-            # with "all" and only error out if neither exists.
-            if (-e "$options->{root}/$archives/${pkg}_${ver}_$arch.deb") {
-                push @essential_pkgs, "$archives/${pkg}_${ver}_$arch.deb";
-            } elsif (-e "$options->{root}/$archives/${pkg}_${ver}_all.deb") {
-                push @essential_pkgs, "$archives/${pkg}_${ver}_all.deb";
-            } else {
-                error(  "cannot find package for $pkg:$arch (= $ver_epoch) "
-                      . "in /var/cache/apt/archives/");
-            }
-        }
-    } else {
-        # collect the .deb files that were downloaded by apt from the content
-        # of /var/cache/apt/archives/
-        if (!$options->{dryrun}) {
-            my $apt_archives = "/var/cache/apt/archives/";
-            opendir my $dh, "$options->{root}/$apt_archives"
-              or error "cannot read $apt_archives";
-            while (my $deb = readdir $dh) {
-                if ($deb !~ /\.deb$/) {
-                    next;
-                }
-                $deb = "$apt_archives/$deb";
-                if (!-f "$options->{root}/$deb") {
-                    next;
-                }
+    # strip the the chroot directory from the filenames
+    foreach my $deb (@dl_debs) {
+        if (rindex $deb, $options->{root}, 0) {
+            if (-e "$options->{root}/$deb") {
                 push @essential_pkgs, $deb;
+            } else {
+                error "package file $deb not accessible from chroot directory"
+                  . " -- use copy:// instead of file:// or a bind-mount";
             }
-            closedir $dh;
-
-            if (scalar @essential_pkgs == 0) {
-                # check if a file:// URI was used
-                open(my $pipe_apt, '-|', 'apt-get', 'indextargets', '--format',
-                    '$(URI)', 'Created-By: Packages')
-                  or error "cannot start apt-get indextargets: $!";
-                while (my $uri = <$pipe_apt>) {
-                    if ($uri =~ /^file:\/\//) {
-                        error
-                          "nothing got downloaded -- use copy:// instead of"
-                          . " file://";
-                    }
-                }
-                error "nothing got downloaded";
-            }
+            next;
+        }
+        if (-e $deb) {
+            push @essential_pkgs, substr($deb, length($options->{root}));
+        } else {
+            error "cannot find package file $deb";
         }
     }
-    # Unpack order matters. Since we create this list using two different
-    # methods but we want both methods to have the same result, we sort the
-    # list before returning it.
-    @essential_pkgs = sort @essential_pkgs;
 
     return (\@essential_pkgs, \@cached_debs);
 }
@@ -6703,15 +6579,13 @@ the B<setup> step. This can be disabled using B<--skip=update>.
 
 =item B<download>
 
-Checks whether F</var/cache/apt/archives/> is empty. This can be disabled with
-B<--skip=download/empty>. In the B<extract> and B<custom> variants, C<apt-get
---download-only install> is used to download all the packages requested via the
-B<--include> option. The B<apt> variant uses the fact that libapt treats the
-C<apt> packages as implicitly essential to download only all C<Essential:yes>
-packages plus apt using C<apt-get --download-only dist-upgrade>. In the
-remaining variants, all Packages files downloaded by the B<update> step are
-inspected to find the C<Essential:yes> package set as well as all packages of
-the required priority.
+In the B<extract> and B<custom> variants, C<apt-get install> is used to
+download all the packages requested via the B<--include> option. The B<apt>
+variant uses the fact that libapt treats the C<apt> packages as implicitly
+essential to download only all C<Essential:yes> packages plus apt using
+C<apt-get dist-upgrade>. In the remaining variants, all Packages files
+downloaded by the B<update> step are inspected to find the C<Essential:yes>
+package set as well as all packages of the required priority.
 
 =item B<extract>
 
@@ -6939,7 +6813,7 @@ apt-cacher-ng, you can use the B<sync-in> and B<sync-out> special hooks to
 synchronize a directory outside the chroot with F</var/cache/apt/archives>
 inside the chroot.
 
-    $ mmdebstrap --variant=apt --skip=download/empty --skip=essential/unlink \
+    $ mmdebstrap --variant=apt --skip=essential/unlink \
         --setup-hook='mkdir -p ./cache "$1"/var/cache/apt/archives/' \
         --setup-hook='sync-in ./cache /var/cache/apt/archives/' \
         --customize-hook='sync-out /var/cache/apt/archives ./cache' \
@@ -7080,12 +6954,6 @@ as the non-root user, then as a workaround you could run C<chmod 600
 /etc/dpkg/dpkg.cfg.d/*> so that the config files are only accessible by the
 root user. See Debian bug #808203.
 
-The C<file://> URI type cannot be used to install the essential packages. This
-is because B<mmdebstrap> uses dpkg to install the packages that apt places into
-F</var/cache/apt/archives> but with C<file://> apt will not copy the files even
-with C<--download-only>. Use C<copy://> instead, which is equivalent to
-C<file://> but copies the archives into F</var/cache/apt/archives>.
-
 With apt versions before 2.1.16, setting C<[trusted=yes]> or
 C<Acquire::AllowInsecureRepositories "1"> to allow signed archives without a
 known public key or unsigned archives will fail because of a gpg warning in the

proxysolver

@@ -1,56 +0,0 @@
-#!/usr/bin/env python3
-#
-# This script is in the public domain
-#
-# Author: Johannes Schauer Marin Rodrigues <josch@mister-muffin.de>
-#
-# thin layer around /usr/lib/apt/solvers/apt, so that we can capture the solver
-# result
-#
-# we set Debug::EDSP::WriteSolution=yes so that Install stanzas also come with
-# Package and Version fields. That way, we do not also have to parse the EDSP
-# request and spend time matching ID numbers
-
-import subprocess
-import sys
-import os
-import getpass
-
-if not os.path.exists("/usr/lib/apt/solvers/apt"):
-    print(
-        """Error: ERR_NO_SOLVER
-Message: The external apt solver doesn't exist. You must install the apt-utils package.
-"""
-    )
-    exit()
-
-fname = os.environ.get("APT_EDSP_DUMP_FILENAME")
-if fname is None:
-    print(
-        """Error: ERR_NO_FILENAME
-Message: You have to set the environment variable APT_EDSP_DUMP_FILENAME
- to a valid filename to store the dump of EDSP solver input in.
- For example with: export APT_EDSP_DUMP_FILENAME=/tmp/dump.edsp
-"""
-    )
-    exit()
-
-try:
-    with open(fname, "w") as f:
-        with subprocess.Popen(
-            ["/usr/lib/apt/solvers/apt", "-oDebug::EDSP::WriteSolution=yes"],
-            stdin=sys.stdin.fileno(),
-            stdout=subprocess.PIPE,
-            bufsize=0,  # unbuffered
-            text=True,  # open in text mode
-        ) as p:
-            for line in p.stdout:
-                print(line, end="")
-                f.write(line)
-except (FileNotFoundError, PermissionError) as e:
-    print(
-        """Error: ERR_CREATE_FILE
-Message: Writing EDSP solver input to file '%s' failed as it couldn't be created!
-"""
-        % fname
-    )