move many functions from urpm.pm to urpm/media.pm

6 files changed, 1915 insertions, 20 deletions

diff --git a/urpm/bug_report.pm b/urpm/bug_report.pm
index e9666d13..eb1258a4 100644
--- a/urpm/bug_report.pm
+++ b/urpm/bug_report.pm
@@ -32,14 +32,14 @@ sub write_urpmdb {
 	#- take care of virtual medium this way.
 	$_->{hdlist} ||= "hdlist.$_->{name}.cz";
 	#- now build directly synthesis file, this is by far the simplest method.
-	if (urpm::is_valid_medium($_)) {
+	if (urpm::media::is_valid_medium($_)) {
 	    $urpm->build_synthesis(start => $_->{start}, end => $_->{end}, synthesis => "$bug_report_dir/synthesis.$_->{hdlist}");
 	    $urpm->{log}(N("built hdlist synthesis file for medium \"%s\"", $_->{name}));
 	}
     }
     #- fake configuration written to convert virtual media on the fly.
     local $urpm->{config} = "$bug_report_dir/urpmi.cfg";
-    $urpm->write_config;
+    urpm::media::write_config($urpm);
 }
 
 sub copy_requested {
diff --git a/urpm/download.pm b/urpm/download.pm
index 2a60a4eb..0b6b94e9 100644
--- a/urpm/download.pm
+++ b/urpm/download.pm
@@ -11,7 +11,7 @@ use Exporter;
 our @ISA = 'Exporter';
 our @EXPORT = qw(get_proxy
 	propagate_sync_callback
-	sync_file sync_prozilla sync_wget sync_curl sync_rsync sync_ssh
+	sync_file sync_rsync sync_ssh
 	set_proxy_config dump_proxy_config
 );
 
@@ -24,6 +24,20 @@ my $proxy_config;
 #- Timeout for curl connection and wget operations
 our $CONNECT_TIMEOUT = 60; #-  (in seconds)
 
+
+
+sub ftp_http_downloaders() { qw(curl wget prozilla) }
+
+sub available_ftp_http_downloaders() {
+    my %binaries = (
+	curl => 'curl', 
+	wget => 'wget', 
+	prozilla => 'proz',
+    );
+    grep { -x "/usr/bin/$binaries{$_}" || -x "/bin/$binaries{$_}" } ftp_http_downloaders();
+}
+
+
 #- parses proxy.cfg (private)
 sub load_proxy_config () {
     return if defined $proxy_config;
@@ -294,7 +308,7 @@ sub sync_curl {
 	eval { require Date::Manip };
 
 	#- prepare to get back size and time stamp of each file.
-	open my $curl, join(" ", map { "'$_'" } "/usr/bin/curl",
+	my $cmd = join(" ", map { "'$_'" } "/usr/bin/curl",
 	    "-q", # don't read .curlrc; some toggle options might interfer
 	    ($options->{limit_rate} ? ("--limit-rate", $options->{limit_rate}) : ()),
 	    ($options->{proxy} ? set_proxy({ type => "curl", proxy => $options->{proxy} }) : ()),
@@ -305,7 +319,8 @@ sub sync_curl {
 	    "-s", "-I",
 	    "--anyauth",
 	    (defined $options->{'curl-options'} ? split /\s+/, $options->{'curl-options'} : ()),
-	    @ftp_files) . " |";
+	    @ftp_files);
+	open my $curl, "$cmd |";
 	while (<$curl>) {
 	    if (/Content-Length:\s*(\d+)/) {
 		!$cur_ftp_file || exists($ftp_files_info{$cur_ftp_file}{size})
@@ -353,7 +368,7 @@ sub sync_curl {
     {
 	my @l = (@ftp_files, @other_files);
 	my ($buf, $file); $buf = '';
-	my $curl_pid = open my $curl, join(" ", map { "'$_'" } "/usr/bin/curl",
+	my $cmd = join(" ", map { "'$_'" } "/usr/bin/curl",
 	    "-q", # don't read .curlrc; some toggle options might interfer
 	    ($options->{limit_rate} ? ("--limit-rate", $options->{limit_rate}) : ()),
 	    ($options->{resume} ? ("--continue-at", "-") : ()),
@@ -369,7 +384,8 @@ sub sync_curl {
 	    "--anyauth",
 	    (defined $options->{'curl-options'} ? split /\s+/, $options->{'curl-options'} : ()),
 	    "--stderr", "-", # redirect everything to stdout
-	    @all_files) . " |";
+	    @all_files);
+	my $curl_pid = open(my $curl, "$cmd |");
 	local $/ = \1; #- read input by only one char, this is slow but very nice (and it works!).
 	local $_;
 	while (<$curl>) {
@@ -581,6 +597,85 @@ sub sync_logger {
     }
 }
 
+
+sub requested_ftp_http_downloader {
+    my ($urpm, $media_name) = @_;
+
+    $urpm->{options}{downloader} || #- cmd-line switch
+      $media_name && do {
+	  #- per-media config
+	  require urpm::media; #- help perl_checker
+	  my $m = urpm::media::name2medium($urpm, $media_name);
+	  $m && $m->{downloader};
+      } || $urpm->{global_config}{downloader};
+}
+
+#- $medium can be undef
+#- known options: quiet, resume, callback
+sub sync {
+    my ($urpm, $medium, $files, %options) = @_;
+
+    my %all_options = ( 
+	dir => "$urpm->{cachedir}/partial",
+	proxy => get_proxy($medium),
+	$medium ? (media => $medium->{name}) : (),
+	%options,
+    );
+    foreach my $cpt (qw(compress limit_rate retry wget-options curl-options rsync-options prozilla-options)) {
+	$all_options{$cpt} = $urpm->{options}{$cpt} if defined $urpm->{options}{$cpt};
+    }
+
+    eval { _sync_webfetch_raw($urpm, $files, \%all_options); 1 };
+}
+
+#- syncing algorithms.
+sub _sync_webfetch_raw {    
+    my ($urpm, $files, $options) = @_;
+
+    my %files;
+    #- currently ftp and http protocols are managed by curl or wget,
+    #- ssh and rsync protocols are managed by rsync *AND* ssh.
+    foreach (@$files) {
+	my $proto = urpm::protocol_from_url($_) or die N("unknown protocol defined for %s", $_);
+	push @{$files{$proto}}, $_;
+    }
+    if ($files{removable} || $files{file}) {
+	my @l = map { urpm::file_from_local_url($_) } @{$files{removable} || []}, @{$files{file} || []};
+	eval { sync_file($options, @l) };
+	$urpm->{fatal}(10, $@) if $@;
+	delete @files{qw(removable file)};
+    }
+    if ($files{ftp} || $files{http} || $files{https}) {
+	my @available = urpm::download::available_ftp_http_downloaders();
+
+	#- use user default downloader if provided and available
+	my $requested_downloader = requested_ftp_http_downloader($urpm, $options->{media});
+	my ($preferred) = grep { $_ eq $requested_downloader } @available;
+	if (!$preferred) {
+	    #- else first downloader of @available is the default one
+	    $preferred = $available[0];
+	    if ($requested_downloader && !our $webfetch_not_available) {
+		$urpm->{log}(N("%s is not available, falling back on %s", $requested_downloader, $preferred));
+		$webfetch_not_available = 1;
+	    }
+	}
+	my $sync = $urpm::download::{"sync_$preferred"} or die N("no webfetch found, supported webfetch are: %s\n", join(", ", urpm::download::ftp_http_downloaders()));
+	$sync->($options, @{$files{ftp} || []}, @{$files{http} || []}, @{$files{https} || []});
+
+	delete @files{qw(ftp http https)};
+    }
+    if ($files{rsync}) {
+	sync_rsync($options, @{$files{rsync}});
+	delete $files{rsync};
+    }
+    if ($files{ssh}) {
+	my @ssh_files = map { m!^ssh://([^/]*)(.*)! ? "$1:$2" : () } @{$files{ssh}};
+	sync_ssh($options, @ssh_files);
+	delete $files{ssh};
+    }
+    %files and die N("unable to handle protocol: %s", join ', ', keys %files);
+}
+
 1;
 
 __END__
diff --git a/urpm/ldap.pm b/urpm/ldap.pm
index 6298f422..5c4d636f 100644
--- a/urpm/ldap.pm
+++ b/urpm/ldap.pm
@@ -38,7 +38,7 @@ therefore, caching is useless if server is up.
 
 Checks if the ldap medium has all required attributes.
 
-=item read_ldap_cache($urpm, %options)
+=item read_ldap_cache($urpm)
 
 Reads the cache created by the C<write_ldap_cache> function. Should be called
 if the ldap server doesn't answer (upgrade, network problem, mobile user, etc.)
@@ -47,7 +47,7 @@ if the ldap server doesn't answer (upgrade, network problem, mobile user, etc.)
 
 Cleans the ldap cache, removes all files in the directory.
 
-=item load_ldap_media($urpm, %options)
+=item load_ldap_media($urpm)
 
 Loads urpmi media configuration from ldap.
 
@@ -97,13 +97,13 @@ sub get_vars_from_sh {
     %l;
 }
 
-sub read_ldap_cache($%) {
-    my ($urpm, %options) = @_;
+sub read_ldap_cache {
+    my ($urpm) = @_;
     foreach (glob("$urpm->{cachedir}/ldap/*")) {
 	! -f $_ and next;
 	my %medium = get_vars_from_sh($_);
 	next if !check_ldap_medium(\%medium);
-	$urpm->probe_medium(\%medium, %options) and push @{$urpm->{media}}, \%medium;
+	urpm::media::add_existing_medium($urpm, \%medium);
     }
 }
 
@@ -146,8 +146,8 @@ my %ldap_changed_attributes = (
     'ftp-proxy' => 'ftp_proxy',
 );
 
-sub load_ldap_media($%) {
-    my ($urpm, %options) = @_;
+sub load_ldap_media {
+    my ($urpm) = @_;
 
     my $config = get_ldap_config() or return;
 
@@ -205,13 +205,13 @@ sub load_ldap_media($%) {
             $medium->{ldap} = 1;
 	    $medium->{priority} = $priority++;
             next if !check_ldap_medium($medium);
-            $urpm->probe_medium($medium, %options) and push @{$urpm->{media}}, $medium;
+            urpm::media::add_existing_medium($urpm, $medium);
             write_ldap_cache($urpm,$medium); 
         }
     };
     if ($@) {
         $urpm->{log}($@);
-        read_ldap_cache($urpm, %options);
+        read_ldap_cache($urpm);
     }
 
 }
diff --git a/urpm/md5sum.pm b/urpm/md5sum.pm
index 829e0dfd..f5295190 100644
--- a/urpm/md5sum.pm
+++ b/urpm/md5sum.pm
@@ -40,8 +40,8 @@ sub on_local_medium {
 sub compute_on_local_medium {
     my ($urpm, $medium) = @_;
 
-    require urpm; #- help perl_checker
-    my $f = urpm::statedir_hdlist_or_synthesis($urpm, $medium);
+    require urpm::media; #- help perl_checker
+    my $f = urpm::media::statedir_hdlist_or_synthesis($urpm, $medium);
     $urpm->{log}(N("computing md5sum of existing source hdlist (or synthesis) [%s]", $f));
     -e $f && compute($f);
 }
diff --git a/urpm/media.pm b/urpm/media.pm
new file mode 100644
index 00000000..e32ae406
--- /dev/null
+++ b/urpm/media.pm
@@ -0,0 +1,1800 @@
+package urpm::media;
+
+# $Id$
+
+use urpm 'file_from_local_url';
+use urpm::msg;
+use urpm::util;
+
+
+our @PER_MEDIA_OPT = qw(
+    downloader
+    hdlist
+    ignore
+    key-ids
+    list
+    md5sum
+    noreconfigure
+    priority
+    priority-upgrade
+    removable
+    static
+    synthesis
+    update
+    url
+    verify-rpm
+    virtual
+    with_hdlist
+);
+
+sub read_private_netrc {
+    my ($urpm) = @_;
+
+    my @words = split(/\s+/, scalar cat_($urpm->{private_netrc}));
+    my @l;
+    my $e;
+    while (@words) {
+	my $keyword = shift @words;
+	if ($keyword eq 'machine') {
+	    push @l, $e = { machine => shift(@words) };
+	} elsif ($keyword eq 'default') {
+	    push @l, $e = { default => '' };
+	} elsif ($keyword eq 'login' || $keyword eq 'password' || $keyword eq 'account') {
+	    $e->{$keyword} = shift(@words);
+	} else {
+	    $urpm->{error}("unknown netrc command $keyword");
+	}
+    }
+    @l;
+}
+
+sub parse_url_with_login {
+    my ($url) = @_;
+    $url =~ m!([^:]*)://([^/:\@]*)(:([^/:\@]*))?\@([^/]*)(.*)! &&
+      { proto => $1, login => $2, password => $4, machine => $5, dir => $6 };
+}
+
+sub read_config_add_passwords {
+    my ($urpm, $config) = @_;
+
+    my @netrc = read_private_netrc($urpm) or return;
+    foreach (values %$config) {
+	my $u = parse_url_with_login($_->{url}) or next;
+	if (my ($e) = grep { ($_->{default} || $_->{machine} eq $u->{machine}) && $_->{login} eq $u->{login} } @netrc) {
+	    $_->{url} = sprintf('%s://%s:%s@%s%s', $u->{proto}, $u->{login}, $e->{password}, $u->{machine}, $u->{dir});
+	} else {
+	    $urpm->{log}("no password found for $u->{login}@$u->{machine}");
+	}
+    }
+}
+
+sub remove_passwords_and_write_private_netrc {
+    my ($urpm, $config) = @_;
+
+    my @l;
+    foreach (values %$config) {
+	my $u = parse_url_with_login($_->{url}) or next;
+	#- check whether a password is visible
+	$u->{password} or next;
+
+	push @l, $u;
+	$_->{url} = sprintf('%s://%s@%s%s', $u->{proto}, $u->{login}, $u->{machine}, $u->{dir});
+    }
+    {
+	my $fh = urpm::sys::open_safe($urpm, '>', $urpm->{private_netrc}) or return;
+	foreach my $u (@l) {
+	    printf $fh "machine %s login %s password %s\n", $u->{machine}, $u->{login}, $u->{password};
+	}
+    }
+    chmod 0600, $urpm->{private_netrc};
+}
+
+#- handle deprecated way of saving passwords
+sub recover_url_from_list {
+    my ($urpm, $medium) = @_;
+
+    #- /./ is end of url marker in list file (typically generated by a
+    #- find . -name "*.rpm" > list
+    #- for exportable list file.
+    if (my @probe = map { m!^(.*)/\./! || m!^(.*)/[^/]*$! } cat_(statedir_list($urpm, $medium))) {
+	($medium->{url}) = sort { length($a) <=> length($b) } @probe;
+	$urpm->{modified} = 1; #- ensure urpmi.cfg is handled using only partially hidden url + netrc, since file list won't be generated anymore
+    }
+}
+
+#- Loads /etc/urpmi/urpmi.cfg and performs basic checks.
+#- Does not handle old format: <name> <url> [with <path_hdlist>]
+#- options :
+#-    - nocheck_access : don't check presence of hdlist and other files
+sub read_config {
+    my ($urpm, $b_nocheck_access) = @_;
+    return if $urpm->{media}; #- media already loaded
+    $urpm->{media} = [];
+    my $config = urpm::cfg::load_config($urpm->{config})
+	or $urpm->{fatal}(6, $urpm::cfg::err);
+
+    #- global options
+    if (my $global = $config->{''}) {
+	foreach my $opt (keys %$global) {
+	    if (defined $global->{$opt} && !exists $urpm->{options}{$opt}) {
+		$urpm->{options}{$opt} = $global->{$opt};
+	    }
+	}
+    }
+
+    #- per-media options
+
+    read_config_add_passwords($urpm, $config);
+
+    foreach my $m (grep { $_ ne '' } keys %$config) {
+	my $medium = { name => $m };
+	foreach my $opt (@PER_MEDIA_OPT) {
+	    defined $config->{$m}{$opt} and $medium->{$opt} = $config->{$m}{$opt};
+	}
+
+	if (!$medium->{url}) {
+	    #- recover the url the old deprecated way...
+	    #- only useful for migration, new urpmi.cfg will use netrc
+	    recover_url_from_list($urpm, $medium);
+	    $medium->{url} or $urpm->{error}("unable to find url in list file $medium->{name}, medium ignored");
+	}
+
+	add_existing_medium($urpm, $medium, $b_nocheck_access);
+    }
+
+    eval { require urpm::ldap; urpm::ldap::load_ldap_media($urpm) };
+
+    #- load default values
+    foreach (qw(post-clean verify-rpm)) {
+	exists $urpm->{options}{$_} or $urpm->{options}{$_} = 1;
+    }
+
+    $urpm->{media} = [ sort { $a->{priority} <=> $b->{priority} } @{$urpm->{media}} ];
+
+    #- read MD5 sums (usually not in urpmi.cfg but in a separate file)
+    foreach (@{$urpm->{media}}) {
+	if (my $md5sum = urpm::md5sum::from_MD5SUM("$urpm->{statedir}/MD5SUM", statedir_hdlist_or_synthesis($urpm, $_))) {
+	    $_->{md5sum} = $md5sum;
+	}
+    }
+
+    #- remember global options for write_config
+    $urpm->{global_config} = $config->{''};
+}
+
+#- if invalid, set {ignore}
+sub check_existing_medium {
+    my ($urpm, $medium, $b_nocheck_access) = @_;
+
+    if ($medium->{virtual}) {
+	#- a virtual medium needs to have an url available without using a list file.
+	if ($medium->{hdlist} || $medium->{list}) {
+	    $medium->{ignore} = 1;
+	    $urpm->{error}(N("virtual medium \"%s\" should not have defined hdlist or list file, medium ignored",
+			     $medium->{name}));
+	}
+	unless ($medium->{url}) {
+	    $medium->{ignore} = 1;
+	    $urpm->{error}(N("virtual medium \"%s\" should have a clear url, medium ignored",
+			     $medium->{name}));
+	}
+    } else {
+	if ($medium->{hdlist}) {
+	    #- is this check really needed? keeping just in case
+	    $medium->{hdlist} ne 'list' && $medium->{hdlist} ne 'pubkey' or
+	      $medium->{ignore} = 1,
+		$urpm->{error}(N("invalid hdlist name"));
+	}
+	if (!$medium->{ignore} && !$medium->{hdlist}) {
+	    $medium->{hdlist} = "hdlist.$medium->{name}.cz";
+	    -e statedir_hdlist($urpm, $medium) or
+	      $medium->{ignore} = 1,
+		$urpm->{error}(N("unable to find hdlist file for \"%s\", medium ignored", $medium->{name}));
+	}
+	if (!$medium->{ignore} && !$medium->{list}) {
+	    unless (defined $medium->{url}) {
+		$medium->{list} = "list.$medium->{name}";
+		unless (-e statedir_list($urpm, $medium)) {
+		    $medium->{ignore} = 1,
+		      $urpm->{error}(N("unable to find list file for \"%s\", medium ignored", $medium->{name}));
+		}
+	    }
+	}
+    }
+
+
+    #- check the presence of hdlist and list files if necessary.
+    if (!$b_nocheck_access && !$medium->{ignore}) {
+	if ($medium->{virtual} && -r hdlist_or_synthesis_for_virtual_medium($medium)) {}
+	elsif (-r statedir_hdlist($urpm, $medium)) {}
+	elsif ($medium->{synthesis} && -r statedir_synthesis($urpm, $medium)) {}
+	else {
+	    $medium->{ignore} = 1;
+	    $urpm->{error}(N("unable to access hdlist file of \"%s\", medium ignored", $medium->{name}));
+	}
+	if ($medium->{list} && -r statedir_list($urpm, $medium)) {}
+	elsif ($medium->{url}) {}
+	else {
+	    $medium->{ignore} = 1;
+	    $urpm->{error}(N("unable to access list file of \"%s\", medium ignored", $medium->{name}));
+	}
+    }
+
+    foreach my $field ('hdlist', 'list') {
+	$medium->{$field} or next;
+	if (grep { $_->{$field} eq $medium->{$field} } @{$urpm->{media}}) {
+	    $medium->{ignore} = 1;
+	    $urpm->{error}(
+		$field eq 'hdlist'
+		  ? N("medium \"%s\" trying to use an already used hdlist, medium ignored", $medium->{name})
+		  : N("medium \"%s\" trying to use an already used list, medium ignored",   $medium->{name}));
+	}
+    }
+}
+
+#- probe medium to be used, take old medium into account too.
+sub add_existing_medium {
+    my ($urpm, $medium, $b_nocheck_access) = @_;
+
+    if (name2medium($urpm, $medium->{name})) {
+	$urpm->{error}(N("trying to override existing medium \"%s\", skipping", $medium->{name}));
+	return;
+    }
+
+    check_existing_medium($urpm, $medium, $b_nocheck_access);
+
+    #- probe removable device.
+    probe_removable_device($urpm, $medium);
+
+    #- clear URLs for trailing /es.
+    $medium->{url} and $medium->{url} =~ s|(.*?)/*$|$1|;
+
+    push @{$urpm->{media}}, $medium;
+}
+
+sub file_from_file_url {
+    my ($url) = @_;
+    $url =~ m!^(?:file:/)?(/.*)! && $1;
+}
+
+sub _hdlist_dir {
+    my ($medium) = @_;
+    my $base = file_from_file_url($medium->{url}) || $medium->{url};
+    $medium->{with_hdlist} && reduce_pathname("$base/$medium->{with_hdlist}/..");
+}
+sub _url_with_hdlist {
+    my ($medium) = @_;
+
+    my $base = file_from_file_url($medium->{url}) || $medium->{url};
+    $medium->{with_hdlist} && reduce_pathname("$base/$medium->{with_hdlist}");
+}
+sub hdlist_or_synthesis_for_virtual_medium {
+    my ($medium) = @_;
+    file_from_file_url($medium->{url}) && _url_with_hdlist($medium);
+}
+
+sub statedir_hdlist_or_synthesis {
+    my ($urpm, $medium) = @_;
+    $medium->{hdlist} && "$urpm->{statedir}/" . ($medium->{synthesis} ? 'synthesis.' : '') . $medium->{hdlist};
+}
+sub statedir_hdlist {
+    my ($urpm, $medium) = @_;
+    $medium->{hdlist} && "$urpm->{statedir}/$medium->{hdlist}";
+}
+sub statedir_synthesis {
+    my ($urpm, $medium) = @_;
+    $medium->{hdlist} && "$urpm->{statedir}/synthesis.$medium->{hdlist}";
+}
+sub statedir_list {
+    my ($urpm, $medium) = @_;
+    $medium->{list} && "$urpm->{statedir}/$medium->{list}";
+}
+sub statedir_descriptions {
+    my ($urpm, $medium) = @_;
+    $medium->{name} && "$urpm->{statedir}/descriptions.$medium->{name}";
+}
+sub statedir_names {
+    my ($urpm, $medium) = @_;
+    $medium->{name} && "$urpm->{statedir}/names.$medium->{name}";
+}
+sub cachedir_hdlist {
+    my ($urpm, $medium) = @_;
+    $medium->{hdlist} && "$urpm->{cachedir}/partial/$medium->{hdlist}";
+}
+sub cachedir_list {
+    my ($urpm, $medium) = @_;
+    $medium->{list} && "$urpm->{cachedir}/partial/$medium->{list}";
+}
+
+sub name2medium {
+    my ($urpm, $name) = @_;
+    my ($medium) = grep { $_->{name} eq $name } @{$urpm->{media}};
+    $medium;
+}
+
+#- probe device associated with a removable device.
+sub probe_removable_device {
+    my ($urpm, $medium) = @_;
+
+    if ($medium->{url} && $medium->{url} =~ /^removable/) {
+	#- try to find device name in url scheme, this is deprecated, use medium option "removable" instead
+	if ($medium->{url} =~ /^removable_?([^_:]*)/) {
+	    $medium->{removable} ||= $1 && "/dev/$1";
+	}
+    } else {
+	delete $medium->{removable};
+	return;
+    }
+
+    #- try to find device to open/close for removable medium.
+    if (my $dir = file_from_local_url($medium->{url})) {
+	my %infos;
+	my @mntpoints = urpm::sys::find_mntpoints($dir, \%infos);
+	if (@mntpoints > 1) {	#- return value is suitable for an hash.
+	    $urpm->{log}(N("too many mount points for removable medium \"%s\"", $medium->{name}));
+	    $urpm->{log}(N("taking removable device as \"%s\"", join ',', map { $infos{$_}{device} } @mntpoints));
+	}
+	if (urpm::is_iso($medium->{removable})) {
+	    $urpm->{log}(N("Medium \"%s\" is an ISO image, will be mounted on-the-fly", $medium->{name}));
+	} elsif (@mntpoints) {
+	    if ($medium->{removable} && $medium->{removable} ne $infos{$mntpoints[-1]}{device}) {
+		$urpm->{log}(N("using different removable device [%s] for \"%s\"",
+			       $infos{$mntpoints[-1]}{device}, $medium->{name}));
+	    }
+	    $medium->{removable} = $infos{$mntpoints[-1]}{device};
+	} else {
+	    $urpm->{error}(N("unable to retrieve pathname for removable medium \"%s\"", $medium->{name}));
+	}
+    } else {
+	$urpm->{error}(N("unable to retrieve pathname for removable medium \"%s\"", $medium->{name}));
+    }
+}
+
+
+sub write_MD5SUM {
+    my ($urpm) = @_;
+
+    #- write MD5SUM file
+    my $fh = urpm::sys::open_safe($urpm, '>', "$urpm->{statedir}/MD5SUM") or return 0;
+    foreach my $medium (grep { $_->{md5sum} } @{$urpm->{media}}) {
+	my $s = basename(statedir_hdlist_or_synthesis($urpm, $medium));
+	print $fh "$medium->{md5sum}  $s\n";
+    }
+
+    $urpm->{log}(N("wrote %s", "$urpm->{statedir}/MD5SUM"));
+
+    delete $urpm->{md5sum_modified};
+}
+
+#- Writes the urpmi.cfg file.
+sub write_urpmi_cfg {
+    my ($urpm) = @_;
+
+    #- avoid trashing exiting configuration if it wasn't loaded
+    $urpm->{media} or return;
+
+    my $config = {
+	#- global config options found in the config file, without the ones
+	#- set from the command-line
+	'' => $urpm->{global_config},
+    };
+    foreach my $medium (@{$urpm->{media}}) {
+	next if $medium->{external};
+	my $medium_name = $medium->{name};
+
+	foreach (@PER_MEDIA_OPT) {
+	    defined $medium->{$_} and $config->{$medium_name}{$_} = $medium->{$_};
+	}
+    }
+    remove_passwords_and_write_private_netrc($urpm, $config);
+
+    urpm::cfg::dump_config($urpm->{config}, $config)
+	or $urpm->{fatal}(6, N("unable to write config file [%s]", $urpm->{config}));
+
+    $urpm->{log}(N("wrote config file [%s]", $urpm->{config}));
+
+    #- everything should be synced now.
+    delete $urpm->{modified};
+}
+
+sub write_config {
+    my ($urpm) = @_;
+
+    write_urpmi_cfg($urpm);
+    write_MD5SUM($urpm);
+}
+
+#- read urpmi.cfg file as well as necessary synthesis files
+#- options :
+#-	root
+#-	cmdline_skiplist
+#-      nocheck_access (used by read_config)
+#-
+#-	callback (urpmf)
+#-	need_hdlist (for urpmf: to be able to have info not available in synthesis)
+#-	nodepslist (for urpmq: we don't need the hdlist/synthesis)
+#-	no_skiplist (urpmf)
+#-
+#-	synthesis (use this synthesis file, and only this synthesis file)
+#-
+#-	usedistrib (otherwise uses urpmi.cfg)
+#-	parallel
+#-	  media
+#-	  excludemedia
+#-	  sortmedia
+#-
+#-	  update
+#-	  searchmedia
+sub configure {
+    my ($urpm, %options) = @_;
+
+    clean($urpm);
+
+    $options{parallel} && $options{usedistrib} and $urpm->{fatal}(1, N("Can't use parallel mode with use-distrib mode"));
+
+    if ($options{parallel}) {
+	require urpm::parallel;
+	urpm::parallel::configure($urpm, $options{parallel});
+
+	if (!$options{media} && $urpm->{parallel_handler}{media}) {
+	    $options{media} = $urpm->{parallel_handler}{media};
+	    $urpm->{log}->(N("using associated media for parallel mode: %s", $options{media}));
+	}
+    } else {
+	#- nb: can't have both parallel and root
+	$urpm->{root} = $options{root};
+    }
+
+    $urpm->{root} && ! -c "$urpm->{root}/dev/null"
+	and $urpm->{error}(N("there doesn't seem to be devices in the chroot in \"%s\"", $urpm->{root}));
+
+    if ($options{synthesis}) {
+	if ($options{synthesis} ne 'none') {
+	    #- synthesis take precedence over media, update options.
+	    $options{media} || $options{excludemedia} || $options{sortmedia} || $options{update} || $options{usedistrib} || $options{parallel} and
+	      $urpm->{fatal}(1, N("--synthesis cannot be used with --media, --excludemedia, --sortmedia, --update, --use-distrib or --parallel"));
+	    $urpm->parse_synthesis($options{synthesis});
+	    #- synthesis disables the split of transaction (too risky and not useful).
+	    $urpm->{options}{'split-length'} = 0;
+	}
+    } else {
+        if ($options{usedistrib}) {
+            $urpm->{media} = [];
+            add_distrib_media($urpm, "Virtual", $options{usedistrib}, %options, 'virtual' => 1);
+        } else {
+	    read_config($urpm, $options{nocheck_access});
+	    if (!$options{media} && $urpm->{options}{'default-media'}) {
+		$options{media} = $urpm->{options}{'default-media'};
+	    }
+        }
+	if ($options{media}) {
+	    delete $_->{modified} foreach @{$urpm->{media} || []};
+	    select_media($urpm, split /,/, $options{media});
+	    foreach (grep { !$_->{modified} } @{$urpm->{media} || []}) {
+		#- this is only a local ignore that will not be saved.
+		$_->{tempignore} = $_->{ignore} = 1;
+	    }
+	}
+	if ($options{searchmedia}) {
+	   select_media($urpm, $options{searchmedia}); #- Ensure this media has been selected
+	   if (my $medium = name2medium($urpm, $options{searchmedia})) {
+	       $medium->{ignore} and $urpm->{fatal}("searchmedia is ignored");
+	       $medium->{searchmedia} = 1;
+	   }
+	}
+	if ($options{excludemedia}) {
+	    delete $_->{modified} foreach @{$urpm->{media} || []};
+	    foreach (select_media_by_name($urpm, [ split /,/, $options{excludemedia} ])) {
+		$_->{modified} = 1;
+		#- this is only a local ignore that will not be saved.
+		$_->{tempignore} = $_->{ignore} = 1;
+	    }
+	}
+	if ($options{sortmedia}) {
+	    my @sorted_media = map { select_media_by_name($urpm, [$_]) } split(/,/, $options{sortmedia});
+	    my @remaining = difference2($urpm->{media}, \@sorted_media);
+	    $urpm->{media} = [ @sorted_media, @remaining ];
+	}
+	_parse_media($urpm, 0, \%options) if !$options{nodepslist};
+    }
+    #- determine package to withdraw (from skip.list file) only if something should be withdrawn.
+    if (!$options{nodepslist}) {
+	_compute_flags_for_skiplist($urpm, $options{cmdline_skiplist}) if !$options{no_skiplist};
+	_compute_flags_for_instlist($urpm);
+    }
+}
+
+sub _parse_media {
+    my ($urpm, $second_pass, $options) = @_;
+
+    foreach (grep { !$_->{ignore} && (!$options->{update} || $_->{update}) } @{$urpm->{media} || []}) {
+	our $currentmedia = $_; #- hack for urpmf
+	delete @$_{qw(start end)};
+	if ($_->{virtual}) {
+	    if (file_from_file_url($_->{url})) {
+		if ($_->{synthesis}) {
+		    _parse_synthesis($urpm, $_,
+				     hdlist_or_synthesis_for_virtual_medium($_), $options->{callback});
+		} else {
+				#- we'll need a second pass
+		    $second_pass++;
+		    _parse_hdlist($urpm, $_,
+				  hdlist_or_synthesis_for_virtual_medium($_),
+				  $second_pass > 1 ? undef : $options->{callback},
+			      );
+		}
+	    } else {
+		$urpm->{error}(N("virtual medium \"%s\" is not local, medium ignored", $_->{name}));
+		$_->{ignore} = 1;
+	    }
+	} else {
+	    if ($options->{need_hdlist} && file_size(statedir_hdlist($urpm, $_)) > 32) {
+		_parse_hdlist($urpm, $_, statedir_hdlist($urpm, $_), $options->{callback});
+	    } else {
+		if (!_parse_synthesis($urpm, $_,
+				      statedir_synthesis($urpm, $_),
+				      $options->{callback})) {
+		    _parse_hdlist($urpm, $_, statedir_hdlist($urpm, $_), $options->{callback});
+		}
+	    }
+	}
+	unless ($_->{ignore}) {
+	    _check_after_reading_hdlist_or_synthesis($urpm, $_);
+	}
+	unless ($_->{ignore}) {
+	    if ($_->{searchmedia}) {
+		($urpm->{searchmedia}{start}, $urpm->{searchmedia}{end}) = ($_->{start}, $_->{end});
+		$urpm->{log}(N("Search start: %s end: %s",
+			       $urpm->{searchmedia}{start}, $urpm->{searchmedia}{end}));
+		delete $_->{searchmedia};
+	    }
+	}
+    }
+
+    if ($second_pass == 1) {
+	require URPM::Build;
+	$urpm->{log}(N("performing second pass to compute dependencies\n"));
+	$urpm->unresolved_provides_clean;
+	_parse_media($urpm, 1, $options);
+    }
+}
+
+sub _compute_flags_for_skiplist {
+    my ($urpm, $cmdline_skiplist) = @_;
+    my %uniq;
+    $urpm->compute_flags(
+	get_packages_list($urpm->{skiplist}, $cmdline_skiplist),
+	skip => 1,
+	callback => sub {
+	    my ($urpm, $pkg) = @_;
+	    $pkg->is_arch_compat && ! exists $uniq{$pkg->fullname} or return;
+	    $uniq{$pkg->fullname} = undef;
+	    $urpm->{log}(N("skipping package %s", scalar($pkg->fullname)));
+	},
+    );
+}
+
+sub _compute_flags_for_instlist {
+    my ($urpm) = @_;
+
+    my %uniq;
+    $urpm->compute_flags(
+	get_packages_list($urpm->{instlist}),
+	disable_obsolete => 1,
+	callback => sub {
+	    my ($urpm, $pkg) = @_;
+	    $pkg->is_arch_compat && ! exists $uniq{$pkg->fullname} or return;
+	    $uniq{$pkg->fullname} = undef;
+	    $urpm->{log}(N("would install instead of upgrade package %s", scalar($pkg->fullname)));
+	},
+    );
+
+}
+
+#- add a new medium, sync the config file accordingly.
+#- returns the new medium's name. (might be different from the requested
+#- name if index_name was specified)
+#- options: ignore, index_name, nolock, update, virtual
+sub add_medium {
+    my ($urpm, $name, $url, $with_hdlist, %options) = @_;
+
+    #- make sure configuration has been read.
+    $urpm->{media} or die "caller should have used ->read_config or ->configure first";
+    urpm::sys::lock_urpmi_db($urpm, 'exclusive') if !$options{nolock};
+
+    #- if a medium with that name has already been found, we have to exit now
+    my $medium;
+    if (defined $options{index_name}) {
+	my $i = $options{index_name};
+	do {
+	    ++$i;
+	    $medium = name2medium($urpm, $name . $i);
+	} while $medium;
+	$name .= $i;
+    } else {
+	$medium = name2medium($urpm, $name);
+    }
+    $medium and $urpm->{fatal}(5, N("medium \"%s\" already exists", $medium->{name}));
+
+    $url =~ s,/*$,,; #- clear URLs for trailing /es.
+
+    #- creating the medium info.
+    $medium = { name => $name, url => $url, update => $options{update}, modified => 1, ignore => $options{ignore} };
+    if ($options{virtual}) {
+	file_from_file_url($url) or $urpm->{fatal}(1, N("virtual medium needs to be local"));
+	$medium->{virtual} = 1;
+    } else {
+	$medium->{hdlist} = "hdlist.$name.cz";
+	probe_removable_device($urpm, $medium);
+    }
+
+    #- local media have priority, other are added at the end.
+    if (file_from_file_url($url)) {
+	$medium->{priority} = 0.5;
+    } else {
+	$medium->{priority} = 1 + @{$urpm->{media}};
+    }
+
+    $with_hdlist and $medium->{with_hdlist} = $with_hdlist;
+
+    #- create an entry in media list.
+    push @{$urpm->{media}}, $medium;
+
+    $urpm->{log}(N("added medium %s", $name));
+    $urpm->{modified} = 1;
+
+    $options{nolock} or urpm::sys::unlock_urpmi_db($urpm);
+    $name;
+}
+
+#- add distribution media, according to url given.
+#- returns the list of names of added media.
+#- options :
+#- - initial_number : when adding several numbered media, start with this number
+#- - probe_with : if eq 'synthesis', use synthesis instead of hdlists
+#- - ask_media : callback to know whether each media should be added
+#- other options are passed to add_medium(): ignore, nolock, virtual
+sub add_distrib_media {
+    my ($urpm, $name, $url, %options) = @_;
+
+    #- make sure configuration has been read.
+    $urpm->{media} or die "caller should have used ->read_config or ->configure first";
+
+    my $distribconf;
+
+    if (my $dir = file_from_local_url($url)) {
+	$urpm->try_mounting($dir)
+	    or $urpm->{error}(N("unable to mount the distribution medium")), return ();
+	$distribconf = MDV::Distribconf->new($dir, undef);
+	$distribconf->load
+	    or $urpm->{error}(N("this location doesn't seem to contain any distribution")), return ();
+    } else {
+	unlink "$urpm->{cachedir}/partial/media.cfg";
+
+	$distribconf = MDV::Distribconf->new($url, undef);
+	$distribconf->settree('mandriva');
+
+	$urpm->{log}(N("retrieving media.cfg file..."));
+	if (urpm::download::sync($urpm, undef,
+				 [ reduce_pathname($distribconf->getfullpath(undef, 'infodir') . '/media.cfg') ],
+				 quiet => 1)) {
+	    $urpm->{log}(N("...retrieving done"));
+	    $distribconf->parse_mediacfg("$urpm->{cachedir}/partial/media.cfg")
+		or $urpm->{error}(N("unable to parse media.cfg")), return();
+	} else {
+	    $urpm->{error}(N("...retrieving failed: %s", $@));
+	    $urpm->{error}(N("unable to access the distribution medium (no media.cfg file found)"));
+	    return ();
+	}
+    }
+
+    #- cosmetic update of name if it contains spaces.
+    $name =~ /\s/ and $name .= ' ';
+
+    my @newnames;
+    #- at this point, we have found a media.cfg file, so parse it
+    #- and create all necessary media according to it.
+    my $medium = $options{initial_number} || 1;
+
+    foreach my $media ($distribconf->listmedia) {
+        my $skip = 0;
+	# if one of those values is set, by default, we skip adding the media
+	foreach (qw(noauto)) {
+	    $distribconf->getvalue($media, $_) and do {
+		$skip = 1;
+		last;
+	    };
+	}
+        if ($options{ask_media}) {
+            if ($options{ask_media}->(
+                $distribconf->getvalue($media, 'name'),
+                !$skip,
+            )) {
+                $skip = 0;
+            } else {
+                $skip = 1;
+            }
+        }
+        $skip and next;
+
+        my $media_name = $distribconf->getvalue($media, 'name') || '';
+	my $is_update_media = $distribconf->getvalue($media, 'updates_for');
+
+	push @newnames, add_medium($urpm,
+	    $name ? "$media_name ($name$medium)" : $media_name,
+	    reduce_pathname($distribconf->getfullpath($media, 'path')),
+	    offset_pathname(
+		$url,
+		$distribconf->getpath($media, 'path'),
+	    ) . '/' . $distribconf->getpath($media, $options{probe_with} eq 'synthesis' ? 'synthesis' : 'hdlist'),
+	    index_name => $name ? undef : 0,
+	    %options,
+	    # the following override %options
+	    update => $is_update_media ? 1 : undef,
+	);
+	++$medium;
+    }
+    return @newnames;
+}
+
+#- deprecated, use select_media_by_name instead
+sub select_media {
+    my $urpm = shift;
+    my $options = {};
+    if (ref $_[0]) { $options = shift }
+    foreach (select_media_by_name($urpm, [ @_ ], $options->{strict_match})) {
+	#- select medium by setting the modified flag, do not check ignore.
+	$_->{modified} = 1;
+    }
+}
+
+sub select_media_by_name {
+    my ($urpm, $names, $b_strict_match) = @_;
+
+    my %wanted = map { $_ => 1 } @$names;
+
+    #- first the exact matches
+    my @l = grep { delete $wanted{$_->{name}} } @{$urpm->{media}};
+
+    #- check if some arguments don't correspond to the medium name.
+    #- in such case, try to find the unique medium (or list candidate
+    #- media found).
+    foreach (keys %wanted) {
+	my $q = quotemeta;
+	my (@found, @foundi);
+	my $regex  = $b_strict_match ? qr/^$q$/  : qr/$q/;
+	my $regexi = $b_strict_match ? qr/^$q$/i : qr/$q/i;
+	foreach my $medium (@{$urpm->{media}}) {
+	    $medium->{name} =~ $regex  and push @found, $medium;
+	    $medium->{name} =~ $regexi and push @foundi, $medium;
+	}
+	@found = @foundi if !@found;
+
+	if (@found == 0) {
+	    $urpm->{error}(N("trying to select nonexistent medium \"%s\"", $_));
+	} else {
+	    if (@found > 1) {
+		$urpm->{log}(N("selecting multiple media: %s", join(", ", map { qq("$_->{name}") } @found)));
+	    }
+	    #- changed behaviour to select all occurences by default.
+	    push @l, @found;
+	}
+    }
+    @l;
+}
+
+#- deprecated, use remove_media instead
+sub remove_selected_media {
+    my ($urpm) = @_;
+
+    remove_media($urpm, [ grep { $_->{modified} } @{$urpm->{media}} ]);
+}
+
+sub remove_media {
+    my ($urpm, $to_remove) = @_;
+
+    foreach my $medium (@$to_remove) {
+	$urpm->{log}(N("removing medium \"%s\"", $medium->{name}));
+
+	#- mark to re-write configuration.
+	$urpm->{modified} = 1;
+
+	#- remove files associated with this medium.
+	unlink grep { $_ } map { $_->($urpm, $medium) } \&statedir_hdlist, \&statedir_list, \&statedir_synthesis, \&statedir_descriptions, \&statedir_names;
+
+	#- remove proxy settings for this media
+	urpm::download::remove_proxy_media($medium->{name});
+    }
+
+    $urpm->{media} = [ difference2($urpm->{media}, $to_remove) ];
+}
+
+#- return list of synthesis or hdlist reference to probe.
+sub _probe_with_try_list {
+    my ($probe_with) = @_;
+
+    my @probe_synthesis = (
+	"media_info/synthesis.hdlist.cz",
+	"synthesis.hdlist.cz",
+    );
+    my @probe_hdlist = (
+	"media_info/hdlist.cz",
+	"hdlist.cz",
+    );
+    $probe_with =~ /synthesis/
+      ? (@probe_synthesis, @probe_hdlist)
+      : (@probe_hdlist, @probe_synthesis);
+}
+
+sub may_reconfig_urpmi {
+    my ($urpm, $medium) = @_;
+
+    my $f;
+    if (my $dir = file_from_file_url($medium->{url})) {
+	$f = reduce_pathname("$dir/reconfig.urpmi");
+    } else {
+	unlink($f = "$urpm->{cachedir}/partial/reconfig.urpmi");
+	urpm::download::sync($urpm, $medium, [ reduce_pathname("$medium->{url}/reconfig.urpmi") ], quiet => 1);
+    }
+    if (-s $f) {
+	reconfig_urpmi($urpm, $f, $medium->{name});
+    }
+    unlink $f if !file_from_file_url($medium->{url});
+}
+
+#- read a reconfiguration file for urpmi, and reconfigure media accordingly
+#- $rfile is the reconfiguration file (local), $name is the media name
+#-
+#- the format is similar to the RewriteRule of mod_rewrite, so:
+#-    PATTERN REPLACEMENT [FLAG]
+#- where FLAG can be L or N
+#-
+#- example of reconfig.urpmi:
+#-    # this is an urpmi reconfiguration file
+#-    /cooker /cooker/$ARCH
+sub reconfig_urpmi {
+    my ($urpm, $rfile, $name) = @_;
+    -r $rfile or return;
+
+    $urpm->{log}(N("reconfiguring urpmi for media \"%s\"", $name));
+
+    my ($magic, @lines) = cat_($rfile);
+    #- the first line of reconfig.urpmi must be magic, to be sure it's not an error file
+    $magic =~ /^# this is an urpmi reconfiguration file/ or return undef;
+
+    my @replacements;
+    foreach (@lines) {
+	chomp;
+	s/^\s*//; s/#.*$//; s/\s*$//;
+	$_ or next;
+	my ($p, $r, $f) = split /\s+/, $_, 3;
+	push @replacements, [ quotemeta $p, $r, $f || 1 ];
+    }
+
+    my $reconfigured = 0;
+    my @reconfigurable = qw(url with_hdlist);
+
+    my $medium = name2medium($urpm, $name) or return;
+    my %orig = %$medium;
+
+  URLS:
+    foreach my $k (@reconfigurable) {
+	foreach my $r (@replacements) {
+	    if ($medium->{$k} =~ s/$r->[0]/$r->[1]/) {
+		$reconfigured = 1;
+		#- Flags stolen from mod_rewrite: L(ast), N(ext)
+		if ($r->[2] =~ /L/) {
+		    last;
+		} elsif ($r->[2] =~ /N/) { #- dangerous option
+		    redo URLS;
+		}
+	    }
+	}
+	#- check that the new url exists before committing changes (local mirrors)
+	my $file = file_from_local_url($medium->{$k});
+	if ($file && !-e $file) {
+	    %$medium = %orig;
+	    $reconfigured = 0;
+	    $urpm->{log}(N("...reconfiguration failed"));
+	    return;
+	}
+    }
+
+    if ($reconfigured) {
+	$urpm->{log}(N("reconfiguration done"));
+	write_config($urpm);
+    }
+    $reconfigured;
+}
+
+sub _guess_hdlist_suffix {
+    my ($url) = @_;
+    $url =~ m!\bmedia/(\w+)/*\Z! && $1;
+}
+
+sub _hdlist_suffix {
+    my ($medium) = @_;
+    $medium->{with_hdlist} =~ /hdlist(.*?)(?:\.src)?\.cz$/ ? $1 : '';
+}
+
+sub _parse_hdlist_or_synthesis__when_not_modified {
+    my ($urpm, $medium) = @_;
+
+    delete @$medium{qw(start end)};
+    if ($medium->{virtual}) {
+	if (file_from_file_url($medium->{url})) {
+	    _parse_maybe_hdlist_or_synthesis($urpm, $medium, hdlist_or_synthesis_for_virtual_medium($medium));
+	} else {
+	    $urpm->{error}(N("virtual medium \"%s\" is not local, medium ignored", $medium->{name}));
+	    $medium->{ignore} = 1;
+	}
+    } else {
+	if (!_parse_synthesis($urpm, $medium, statedir_synthesis($urpm, $medium))) {
+	    _parse_hdlist($urpm, $medium, statedir_hdlist($urpm, $medium));
+	}
+    }
+    unless ($medium->{ignore}) {
+	_check_after_reading_hdlist_or_synthesis($urpm, $medium);
+    }
+}
+
+sub _parse_hdlist_or_synthesis__virtual {
+    my ($urpm, $medium) = @_;
+
+    if (my $hdlist_or = hdlist_or_synthesis_for_virtual_medium($medium)) {
+	delete $medium->{modified};
+	$medium->{really_modified} = 1;
+	$urpm->{md5sum_modified} = 1;
+	_parse_maybe_hdlist_or_synthesis($urpm, $medium, $hdlist_or);
+	_check_after_reading_hdlist_or_synthesis($urpm, $medium);
+    } else {
+	$urpm->{error}(N("virtual medium \"%s\" should have valid source hdlist or synthesis, medium ignored",
+			 $medium->{name}));
+	$medium->{ignore} = 1;
+    }
+}
+
+#- names.<media_name> is used by external progs (namely for bash-completion)
+sub generate_medium_names {
+    my ($urpm, $medium) = @_;
+
+    unlink statedir_names($urpm, $medium);
+
+    if (my $fh = urpm::sys::open_safe($urpm, ">", statedir_names($urpm, $medium))) {
+	foreach ($medium->{start} .. $medium->{end}) {
+	    if (defined $urpm->{depslist}[$_]) {
+		print $fh $urpm->{depslist}[$_]->name . "\n";
+	    } else {
+		$urpm->{error}(N("Error generating names file: dependency %d not found", $_));
+	    }
+	}
+    } else {
+	$urpm->{error}(N("Error generating names file: Can't write to file (%s)", $!));
+    }
+}
+
+
+sub _read_existing_synthesis_and_hdlist_if_same_time_and_msize {
+    my ($urpm, $medium, $basename) = @_;
+
+    same_size_and_mtime("$urpm->{cachedir}/partial/$basename", 
+			statedir_hdlist($urpm, $medium)) or return;
+
+    unlink "$urpm->{cachedir}/partial/$basename";
+
+    _read_existing_synthesis_and_hdlist($urpm, $medium);
+
+    1;
+}
+
+sub _read_existing_synthesis_and_hdlist_if_same_md5sum {
+    my ($urpm, $medium, $retrieved_md5sum) = @_;
+
+    #- if an existing hdlist or synthesis file has the same md5sum, we assume the
+    #- files are the same.
+    #- if local md5sum is the same as distant md5sum, this means there is no need to
+    #- download hdlist or synthesis file again.
+    $retrieved_md5sum && $medium->{md5sum} eq $retrieved_md5sum or return;
+
+    unlink "$urpm->{cachedir}/partial/" . basename($medium->{with_hdlist});
+
+    _read_existing_synthesis_and_hdlist($urpm, $medium);
+
+    1;
+}
+
+sub _read_existing_synthesis_and_hdlist {
+    my ($urpm, $medium) = @_;
+
+    $urpm->{log}(N("medium \"%s\" is up-to-date", $medium->{name}));
+
+    #- the medium is now considered not modified.
+    $medium->{modified} = 0;
+    #- XXX we could link the new hdlist to the old one.
+    #- (However links need to be managed. see bug #12391.)
+    #- as previously done, just read synthesis file here, this is enough.
+    if (!_parse_synthesis($urpm, $medium, statedir_synthesis($urpm, $medium))) {
+	_parse_hdlist($urpm, $medium, statedir_hdlist($urpm, $medium));
+	_check_after_reading_hdlist_or_synthesis($urpm, $medium);
+    }
+
+    1;
+}
+
+sub _parse_hdlist {
+    my ($urpm, $medium, $hdlist_file, $o_callback) = @_;
+
+    $urpm->{log}(N("examining hdlist file [%s]", $hdlist_file));
+    ($medium->{start}, $medium->{end}) = 
+      $urpm->parse_hdlist($hdlist_file, packing => 1, $o_callback ? (callback => $o_callback) : @{[]});
+}
+
+sub _parse_synthesis {
+    my ($urpm, $medium, $synthesis_file, $o_callback) = @_;
+
+    $urpm->{log}(N("examining synthesis file [%s]", $synthesis_file));
+    ($medium->{start}, $medium->{end}) = 
+      $urpm->parse_synthesis($synthesis_file, $o_callback ? (callback => $o_callback) : @{[]});
+}
+sub _parse_maybe_hdlist_or_synthesis {
+    my ($urpm, $medium, $hdlist_or) = @_;
+
+    if ($medium->{synthesis}) {
+	if (_parse_synthesis($urpm, $medium, $hdlist_or)) {
+	    $medium->{synthesis} = 1;
+	} elsif (_parse_hdlist($urpm, $medium, $hdlist_or)) {
+	    delete $medium->{synthesis};
+	} else {
+	    return;
+	}
+    } else {
+	if (_parse_hdlist($urpm, $medium, $hdlist_or)) {
+	    delete $medium->{synthesis};
+	} elsif (_parse_synthesis($urpm, $medium, $hdlist_or)) {
+	    $medium->{synthesis} = 1;
+	} else {
+	    return;
+	}
+    }
+    1;
+}
+
+sub _build_hdlist_using_rpm_headers {
+    my ($urpm, $medium) = @_;
+
+    $urpm->{log}(N("building hdlist [%s]", statedir_hdlist($urpm, $medium)));
+    #- finish building operation of hdlist.
+    $urpm->build_hdlist(start  => $medium->{start},
+			end    => $medium->{end},
+			dir    => "$urpm->{cachedir}/headers",
+			hdlist => statedir_hdlist($urpm, $medium),
+		    );
+}
+
+sub _build_synthesis {
+    my ($urpm, $medium) = @_;
+
+    eval { $urpm->build_synthesis(
+	start     => $medium->{start},
+	end       => $medium->{end},
+	synthesis => statedir_synthesis($urpm, $medium),
+    ) };
+    if ($@) {
+	$urpm->{error}(N("Unable to build synthesis file for medium \"%s\". Your hdlist file may be corrupted.", $medium->{name}));
+	$urpm->{error}($@);
+	unlink statedir_synthesis($urpm, $medium);
+    } else {
+	$urpm->{log}(N("built hdlist synthesis file for medium \"%s\"", $medium->{name}));
+    }
+    #- keep in mind we have a modified database, sure at this point.
+    $urpm->{md5sum_modified} = 1;
+}
+
+sub is_valid_medium {
+    my ($medium) = @_;
+    defined $medium->{start} && defined $medium->{end};
+}
+
+sub _check_after_reading_hdlist_or_synthesis {
+    my ($urpm, $medium) = @_;
+
+    if (!is_valid_medium($medium)) {
+	$urpm->{error}(N("problem reading hdlist or synthesis file of medium \"%s\"", $medium->{name}));
+	$medium->{ignore} = 1;
+    }
+}
+
+sub _get_list_or_pubkey__local {
+    my ($urpm, $medium, $name) = @_;
+
+    my $path = _hdlist_dir($medium) . "/$name" . _hdlist_suffix($medium);
+    -e $path or $path = file_from_local_url($medium->{url}) . "/$name";
+    if (-e $path) {
+	copy_and_own($path, "$urpm->{cachedir}/partial/$name")
+	  or $urpm->{error}(N("...copying failed")), return;
+    }
+    1;
+}
+
+sub _get_list_or_pubkey__remote {
+    my ($urpm, $medium, $name) = @_;
+
+    my $found;
+    if (_hdlist_suffix($medium)) {
+	my $local_name = $name . _hdlist_suffix($medium);
+
+	if (urpm::download::sync($urpm, $medium, [_hdlist_dir($medium) . "/$local_name"], 
+				 quiet => 1)) {
+	    rename("$urpm->{cachedir}/partial/$local_name", "$urpm->{cachedir}/partial/$name");
+	    $found = 1;
+	}
+    }
+    if (!$found) {
+	urpm::download::sync($urpm, $medium, [reduce_pathname("$medium->{url}/$name")], quiet => 1)
+	    or unlink "$urpm->{cachedir}/partial/$name";
+    }
+}
+
+sub get_descriptions_local {
+    my ($urpm, $medium) = @_;
+
+    unlink statedir_descriptions($urpm, $medium);
+
+    my $dir = file_from_local_url($medium->{url});
+    my $description_file = "$dir/media_info/descriptions"; #- new default location
+    -e $description_file or $description_file = "$dir/../descriptions";
+    -e $description_file or return;
+
+    $urpm->{log}(N("copying description file of \"%s\"...", $medium->{name}));
+    if (copy_and_own($description_file, statedir_descriptions($urpm, $medium))) {
+	$urpm->{log}(N("...copying done"));
+    } else {
+	$urpm->{error}(N("...copying failed"));
+	$medium->{ignore} = 1;
+    }
+}
+sub get_descriptions_remote {
+    my ($urpm, $medium) = @_;
+
+    unlink "$urpm->{cachedir}/partial/descriptions";
+
+    if (-e statedir_descriptions($urpm, $medium)) {
+	urpm::util::move(statedir_descriptions($urpm, $medium), "$urpm->{cachedir}/partial/descriptions");
+    }
+    urpm::download::sync($urpm, $medium, [ reduce_pathname("$medium->{url}/media_info/descriptions") ], quiet => 1) 
+	or #- try older location
+	  urpm::download::sync($urpm, $medium, [ reduce_pathname("$medium->{url}/../descriptions") ], quiet => 1);
+
+    if (-e "$urpm->{cachedir}/partial/descriptions") {
+	urpm::util::move("$urpm->{cachedir}/partial/descriptions", statedir_descriptions($urpm, $medium));
+    }
+}
+sub get_hdlist_or_synthesis__local {
+    my ($urpm, $medium, $callback) = @_;
+
+    unlink cachedir_hdlist($urpm, $medium);
+    $urpm->{log}(N("copying source hdlist (or synthesis) of \"%s\"...", $medium->{name}));
+    $callback and $callback->('copy', $medium->{name});
+    if (copy_and_own(_url_with_hdlist($medium), cachedir_hdlist($urpm, $medium))) {
+	$callback and $callback->('done', $medium->{name});
+	$urpm->{log}(N("...copying done"));
+	if (file_size(cachedir_hdlist($urpm, $medium)) < 20) {
+	    $urpm->{error}(N("copy of [%s] failed (file is suspiciously small)", cachedir_hdlist($urpm, $medium)));
+	    0;
+	} else {
+	    1;
+	}
+    } else {
+	$callback and $callback->('failed', $medium->{name});
+	#- force error, reported afterwards
+	unlink cachedir_hdlist($urpm, $medium);
+	0;
+    }
+}
+
+sub get_hdlist_or_synthesis_and_check_md5sum__local {
+    my ($urpm, $medium, $retrieved_md5sum, $callback) = @_;
+
+    get_hdlist_or_synthesis__local($urpm, $medium, $callback) or return;
+
+    #- keep checking md5sum of file just copied ! (especially on nfs or removable device).
+    if ($retrieved_md5sum) {
+	$urpm->{log}(N("computing md5sum of copied source hdlist (or synthesis)"));
+	urpm::md5sum::compute(cachedir_hdlist($urpm, $medium)) eq $retrieved_md5sum or
+	  $urpm->{error}(N("copy of [%s] failed (md5sum mismatch)", _url_with_hdlist($medium))), return;
+    }
+
+    1;
+}
+
+sub _read_rpms_from_dir {
+    my ($urpm, $medium, $second_pass, $clean_cache) = @_;
+
+    my $dir = file_from_local_url($medium->{url});
+
+    $medium->{rpm_files} = [ glob("$dir/*.rpm") ];
+
+    #- check files contains something good!
+    if (!@{$medium->{rpm_files}}) {
+	$urpm->{error}(N("no rpm files found from [%s]", $dir));
+	$medium->{ignore} = 1;
+	return;
+    }
+
+    #- we need to rebuild from rpm files the hdlist.
+
+    $urpm->{log}(N("reading rpm files from [%s]", $dir));
+    my @unresolved_before = grep {
+	! defined $urpm->{provides}{$_};
+    } keys %{$urpm->{provides} || {}};
+    $medium->{start} = @{$urpm->{depslist}};
+
+    eval {
+	$medium->{headers} = [ $urpm->parse_rpms_build_headers(
+	    dir   => "$urpm->{cachedir}/headers",
+	    rpms  => $medium->{rpm_files},
+	    clean => $$clean_cache,
+	    packing => 1,
+	) ];
+    };
+    if ($@) {
+	$urpm->{error}(N("unable to read rpm files from [%s]: %s", $dir, $@));
+	delete $medium->{headers}; #- do not propagate these.
+	return;
+    }
+
+    $medium->{end} = $#{$urpm->{depslist}};
+    if ($medium->{start} > $medium->{end}) {
+	#- an error occured (provided there are files in input.)
+	delete $medium->{start};
+	delete $medium->{end};
+	$urpm->{fatal}(9, N("no rpms read"));
+    }
+
+    #- make sure the headers will not be removed for another media.
+    $$clean_cache = 0;
+    my @unresolved = grep {
+	! defined $urpm->{provides}{$_};
+    } keys %{$urpm->{provides} || {}};
+    @unresolved_before == @unresolved or $$second_pass = 1;
+
+    delete $medium->{synthesis}; #- when building hdlist by ourself, drop synthesis property.
+    1;
+}
+
+#- options: callback, force, force_building_hdlist, nomd5sum, nopubkey, probe_with
+sub _update_medium__parse_if_unmodified__local {
+    my ($urpm, $medium, $second_pass, $clean_cache, $options) = @_;
+
+    my $dir = file_from_local_url($medium->{url});
+
+    if (!-d $dir) {
+	#- the directory given does not exist and may be accessible
+	#- by mounting some other directory. Try to figure it out and mount
+	#- everything that might be necessary.
+	$urpm->try_mounting(
+	    !$options->{force_building_hdlist} && $medium->{with_hdlist}
+	      ? _hdlist_dir($medium) : $dir,
+	    #- in case of an iso image, pass its name
+	    urpm::is_iso($medium->{removable}) && $medium->{removable},
+	) or $urpm->{error}(N("unable to access medium \"%s\",
+this could happen if you mounted manually the directory when creating the medium.", $medium->{name})), return 'unmodified';
+    }
+
+    #- try to probe for possible with_hdlist parameter, unless
+    #- it is already defined (and valid).
+    if ($options->{probe_with} && !$medium->{with_hdlist}) {
+	foreach (_probe_with_try_list($options->{probe_with})) {
+	    -e "$dir/$_" or next;
+	    if (file_size("$dir/$_") >= 20) {
+		$medium->{with_hdlist} = $_;
+		last;
+	    } else {
+		$urpm->{error}(N("invalid hdlist file %s for medium \"%s\"", "$dir/$_", $medium->{name}));
+		return;
+	    }
+	}
+    }
+
+    if ($medium->{virtual}) {
+	#- syncing a virtual medium is very simple, just try to read the file in order to
+	#- determine its type, once a with_hdlist has been found (but is mandatory).
+	_parse_hdlist_or_synthesis__virtual($urpm, $medium);
+    }
+
+    #- examine if a distant MD5SUM file is available.
+    #- this will only be done if $with_hdlist is not empty in order to use
+    #- an existing hdlist or synthesis file, and to check if download was good.
+    #- if no MD5SUM is available, do it as before...
+    #- we can assume at this point a basename is existing, but it needs
+    #- to be checked for being valid, nothing can be deduced if no MD5SUM
+    #- file is present.
+
+    unless ($medium->{virtual}) {
+	if ($medium->{with_hdlist}) {
+	    my ($retrieved_md5sum);
+
+	    if (!$options->{nomd5sum} && file_size(_hdlist_dir($medium) . '/MD5SUM') > 32) {
+		$retrieved_md5sum = urpm::md5sum::from_MD5SUM__or_warn($urpm, _hdlist_dir($medium) . '/MD5SUM', basename($medium->{with_hdlist}));
+		if (urpm::md5sum::on_local_medium($urpm, $medium, $options->{force})) {
+		    _read_existing_synthesis_and_hdlist_if_same_md5sum($urpm, $medium, $retrieved_md5sum)
+		      and return 'unmodified';
+		}
+	    }
+
+	    #- if the source hdlist is present and we are not forcing using rpm files
+	    if (!$options->{force_building_hdlist} && -e _url_with_hdlist($medium)) {
+		if (get_hdlist_or_synthesis_and_check_md5sum__local($urpm, $medium, $retrieved_md5sum, $options->{callback})) {
+
+		    $medium->{md5sum} = $retrieved_md5sum if $retrieved_md5sum;
+
+		    #- check if the files are equal... and no force copy...
+		    if (!$options->{force}) {
+			_read_existing_synthesis_and_hdlist_if_same_time_and_msize($urpm, $medium, $medium->{hdlist}) 
+			  and return 'unmodified';
+		    }
+		} else {
+		    #- if copying hdlist has failed, try to build it directly.
+		    if ($urpm->{options}{'build-hdlist-on-error'}) {
+			$options->{force_building_hdlist} = 1;
+		    } else {
+			$urpm->{error}(N("unable to access hdlist file of \"%s\", medium ignored", $medium->{name}));
+			$medium->{ignore} = 1;
+			return;
+		    }
+		}
+	    }
+	} else {
+	    #- no available hdlist/synthesis, try to build it from rpms
+	    $options->{force_building_hdlist} = 1;
+	}
+
+	if ($options->{force_building_hdlist}) {
+	    _read_rpms_from_dir($urpm, $medium, $second_pass, $clean_cache) or return;
+	}
+    }
+
+    1;
+}
+
+#- options: callback, force, nomd5sum, nopubkey, probe_with, quiet
+sub _update_medium__parse_if_unmodified__remote {
+    my ($urpm, $medium, $options) = @_;
+    my ($retrieved_md5sum, $basename);
+
+    #- examine if a distant MD5SUM file is available.
+    #- this will only be done if $with_hdlist is not empty in order to use
+    #- an existing hdlist or synthesis file, and to check if download was good.
+    #- if no MD5SUM is available, do it as before...
+    if ($medium->{with_hdlist}) {
+	#- we can assume at this point a basename is existing, but it needs
+	#- to be checked for being valid, nothing can be deduced if no MD5SUM
+	#- file is present.
+	$basename = basename($medium->{with_hdlist});
+
+	unlink "$urpm->{cachedir}/partial/MD5SUM";
+	if (!$options->{nomd5sum} && 
+	      urpm::download::sync($urpm, $medium, 
+				   [ reduce_pathname(_hdlist_dir($medium) . '/MD5SUM') ],
+				   quiet => 1) && file_size("$urpm->{cachedir}/partial/MD5SUM") > 32) {
+	    if (urpm::md5sum::on_local_medium($urpm, $medium, $options->{force} >= 2)) {
+		$retrieved_md5sum = urpm::md5sum::from_MD5SUM__or_warn($urpm, "$urpm->{cachedir}/partial/MD5SUM", $basename);
+		_read_existing_synthesis_and_hdlist_if_same_md5sum($urpm, $medium, $retrieved_md5sum)
+		  and return 'unmodified';
+	    }
+	} else {
+	    #- at this point, we don't if a basename exists and is valid, let probe it later.
+	    $basename = undef;
+	}
+    }
+
+    #- try to probe for possible with_hdlist parameter, unless
+    #- it is already defined (and valid).
+    $urpm->{log}(N("retrieving source hdlist (or synthesis) of \"%s\"...", $medium->{name}));
+    $options->{callback} and $options->{callback}('retrieve', $medium->{name});
+    if ($options->{probe_with} && !$medium->{with_hdlist}) {
+	foreach my $with_hdlist (_probe_with_try_list($options->{probe_with})) {
+	    $basename = basename($with_hdlist) or next;
+	    $options->{force} and unlink "$urpm->{cachedir}/partial/$basename";
+	    if (urpm::download::sync($urpm, $medium, [ reduce_pathname("$medium->{url}/$with_hdlist") ],
+				     quiet => $options->{quiet}, callback => $options->{callback}) && file_size("$urpm->{cachedir}/partial/$basename") >= 20) {
+		$urpm->{log}(N("...retrieving done"));
+		$medium->{with_hdlist} = $with_hdlist;
+		$urpm->{log}(N("found probed hdlist (or synthesis) as %s", $medium->{with_hdlist}));
+		last;	    #- found a suitable with_hdlist in the list above.
+	    }
+	}
+    } else {
+	$basename = basename($medium->{with_hdlist});
+
+	if ($options->{force}) {
+	    unlink "$urpm->{cachedir}/partial/$basename";
+	} else {
+	    #- try to sync (copy if needed) local copy after restored the previous one.
+	    #- this is useful for rsync (?)
+	    if (-e statedir_hdlist_or_synthesis($urpm, $medium)) {
+		copy_and_own(
+		    statedir_hdlist_or_synthesis($urpm, $medium),
+		    "$urpm->{cachedir}/partial/$basename",
+		) or $urpm->{error}(N("...copying failed")), return;
+	    }
+	}
+	if (urpm::download::sync($urpm, $medium, [ _url_with_hdlist($medium) ],
+				 quiet => $options->{quiet}, callback => $options->{callback})) {
+	    $urpm->{log}(N("...retrieving done"));
+	} else {
+	    $urpm->{error}(N("...retrieving failed: %s", $@));
+	    unlink "$urpm->{cachedir}/partial/$basename";
+	}
+    }
+
+    #- check downloaded file has right signature.
+    if (file_size("$urpm->{cachedir}/partial/$basename") >= 20 && $retrieved_md5sum) {
+	$urpm->{log}(N("computing md5sum of retrieved source hdlist (or synthesis)"));
+	unless (urpm::md5sum::compute("$urpm->{cachedir}/partial/$basename") eq $retrieved_md5sum) {
+	    $urpm->{error}(N("...retrieving failed: md5sum mismatch"));
+	    unlink "$urpm->{cachedir}/partial/$basename";
+	}
+    }
+
+    if (file_size("$urpm->{cachedir}/partial/$basename") >= 20) {
+	$options->{callback} and $options->{callback}('done', $medium->{name});
+
+	unless ($options->{force}) {
+	    _read_existing_synthesis_and_hdlist_if_same_time_and_msize($urpm, $medium, $basename)
+	      and return 'unmodified';
+	}
+
+	#- the files are different, update local copy.
+	rename("$urpm->{cachedir}/partial/$basename", cachedir_hdlist($urpm, $medium));
+    } else {
+	$options->{callback} and $options->{callback}('failed', $medium->{name});
+	$urpm->{error}(N("retrieval of source hdlist (or synthesis) failed"));
+	return;
+    }
+    $urpm->{md5sum} = $retrieved_md5sum if $retrieved_md5sum;
+    1;
+}
+
+sub _get_pubkey_and_descriptions {
+    my ($urpm, $medium, $nopubkey) = @_;
+
+    my $local = file_from_local_url($medium->{url});
+
+    ($local ? \&get_descriptions_local : \&get_descriptions_remote)->($urpm, $medium);
+
+    #- examine if a pubkey file is available.
+    if (!$nopubkey && !$medium->{'key-ids'}) {
+	($local ? \&_get_list_or_pubkey__local : \&_get_list_or_pubkey__remote)->($urpm, $medium, 'pubkey');
+    }
+}
+
+sub _read_cachedir_pubkey {
+    my ($urpm, $medium) = @_;
+    -s "$urpm->{cachedir}/partial/pubkey" or return;
+
+    $urpm->{log}(N("examining pubkey file of \"%s\"...", $medium->{name}));
+
+    my %key_ids;
+    $urpm->import_needed_pubkeys(
+	[ $urpm->parse_armored_file("$urpm->{cachedir}/partial/pubkey") ],
+	root => $urpm->{root}, 
+	callback => sub {
+	    my (undef, undef, $_k, $id, $imported) = @_;
+	    if ($id) {
+		$key_ids{$id} = undef;
+		$imported and $urpm->{log}(N("...imported key %s from pubkey file of \"%s\"",
+					     $id, $medium->{name}));
+	    } else {
+		$urpm->{error}(N("unable to import pubkey file of \"%s\"", $medium->{name}));
+	    }
+	});
+    if (keys(%key_ids)) {
+	$medium->{'key-ids'} = join(',', keys %key_ids);
+    }
+}
+
+sub _write_rpm_list {
+    my ($urpm, $medium) = @_;
+
+    @{$medium->{rpm_files} || []} or return;
+
+    $medium->{list} ||= "list.$medium->{name}";
+
+    #- write list file.
+    $urpm->{log}(N("writing list file for medium \"%s\"", $medium->{name}));
+    my $listfh = urpm::sys::open_safe($urpm, '>', cachedir_list($urpm, $medium)) or return;
+    print $listfh basename($_), "\n" foreach @{$medium->{rpm_files}};
+    1;
+}
+
+#- options: callback, force, force_building_hdlist, nomd5sum, probe_with, quiet
+#- (from _update_medium__parse_if_unmodified__local and _update_medium__parse_if_unmodified__remote)
+sub _update_medium_first_pass {
+    my ($urpm, $medium, $second_pass, $clean_cache, %options) = @_;
+
+    #- we should create the associated synthesis file if it does not already exist...
+    file_size(statedir_synthesis($urpm, $medium)) >= 20
+      or $medium->{must_build_synthesis} = 1;
+
+    unless ($medium->{modified}) {
+	#- the medium is not modified, but to compute dependencies,
+	#- we still need to read it and all synthesis will be written if
+	#- an unresolved provides is found.
+	#- to speed up the process, we only read the synthesis at the beginning.
+	_parse_hdlist_or_synthesis__when_not_modified($urpm, $medium);
+	return 1;
+    }
+
+    #- always delete a remaining list file or pubkey file in cache.
+    foreach (qw(list pubkey)) {
+	unlink "$urpm->{cachedir}/partial/$_";
+    }
+
+    #- check for a reconfig.urpmi file (if not already reconfigured)
+    if (!$medium->{noreconfigure}) {
+	may_reconfig_urpmi($urpm, $medium);
+    }
+
+    {
+	my $rc = 
+	  file_from_local_url($medium->{url})
+	    ? _update_medium__parse_if_unmodified__local($urpm, $medium, $second_pass, $clean_cache, \%options)
+	    : _update_medium__parse_if_unmodified__remote($urpm, $medium, \%options);
+
+	if (!$rc || $rc eq 'unmodified') {
+	    return $rc;
+	}
+    }
+
+    #- build list file according to hdlist.
+    if (!$medium->{headers} && !$medium->{virtual} && file_size(cachedir_hdlist($urpm, $medium)) < 20) {
+	$urpm->{error}(N("no hdlist file found for medium \"%s\"", $medium->{name}));
+	return;
+    }
+
+    if (!$medium->{virtual}) {
+	if ($medium->{headers}) {
+	    _write_rpm_list($urpm, $medium) or return;
+	} else {
+	    #- read first pass hdlist or synthesis, try to open as synthesis, if file
+	    #- is larger than 1MB, this is probably an hdlist else a synthesis.
+	    #- anyway, if one tries fails, try another mode.
+	    $options{callback} and $options{callback}('parse', $medium->{name});
+	    my @unresolved_before = grep { ! defined $urpm->{provides}{$_} } keys %{$urpm->{provides} || {}};
+
+	    #- if it looks like a hdlist, try to parse as hdlist first
+	    delete $medium->{synthesis} if file_size(cachedir_hdlist($urpm, $medium)) > 262144;
+	    _parse_maybe_hdlist_or_synthesis($urpm, $medium, cachedir_hdlist($urpm, $medium));
+
+	    if (is_valid_medium($medium)) {
+		$options{callback} && $options{callback}('done', $medium->{name});
+	    } else {
+		$urpm->{error}(N("unable to parse hdlist file of \"%s\"", $medium->{name}));
+		$options{callback} and $options{callback}('failed', $medium->{name});
+		delete $medium->{md5sum};
+
+		#- we have to read back the current synthesis file unmodified.
+		if (!_parse_synthesis($urpm, $medium, statedir_synthesis($urpm, $medium))) {
+		    $urpm->{error}(N("problem reading synthesis file of medium \"%s\"", $medium->{name}));
+		    $medium->{ignore} = 1;
+		}
+		return;
+	    }
+	    delete $medium->{list};
+
+	    {
+		my @unresolved_after = grep { ! defined $urpm->{provides}{$_} } keys %{$urpm->{provides} || {}};
+		@unresolved_before == @unresolved_after or $$second_pass = 1;
+	    }
+	}
+    }
+
+    unless ($medium->{virtual}) {
+	    #- make sure to rebuild base files and clear medium modified state.
+	    $medium->{modified} = 0;
+	    $medium->{really_modified} = 1;
+	    $urpm->{md5sum_modified} = 1;
+
+	    #- but use newly created file.
+	    unlink statedir_hdlist($urpm, $medium);
+	    $medium->{synthesis} and unlink statedir_synthesis($urpm, $medium);
+	    $medium->{list} and unlink statedir_list($urpm, $medium);
+	    unless ($medium->{headers}) {
+		unlink statedir_synthesis($urpm, $medium);
+		unlink statedir_hdlist($urpm, $medium);
+		urpm::util::move(cachedir_hdlist($urpm, $medium),
+				 statedir_hdlist_or_synthesis($urpm, $medium));
+	    }
+	    if ($medium->{list}) {
+		urpm::util::move(cachedir_list($urpm, $medium), statedir_list($urpm, $medium));
+	    }
+
+	    #- and create synthesis file associated.
+	    $medium->{must_build_synthesis} = !$medium->{synthesis};
+    }
+    1;
+}
+
+sub _update_medium_first_pass_failed {
+    my ($urpm, $medium) = @_;
+
+    !$medium->{virtual} or return;
+
+    #- an error has occured for updating the medium, we have to remove temporary files.
+    unlink(glob("$urpm->{cachedir}/partial/*"));
+}
+
+#- take care of modified medium only, or all if all have to be recomputed.
+sub _update_medium_second_pass {
+    my ($urpm, $medium, $callback) = @_;
+
+    $callback and $callback->('parse', $medium->{name});
+
+    #- a modified medium is an invalid medium, we have to read back the previous hdlist
+    #- or synthesis which has not been modified by first pass above.
+
+	if ($medium->{headers} && !$medium->{modified}) {
+	    $urpm->{log}(N("reading headers from medium \"%s\"", $medium->{name}));
+	    ($medium->{start}, $medium->{end}) = $urpm->parse_headers(dir     => "$urpm->{cachedir}/headers",
+								      headers => $medium->{headers},
+								  );
+	} elsif ($medium->{synthesis}) {
+	    if ($medium->{virtual}) {
+		if (file_from_file_url($medium->{url})) {
+		    _parse_synthesis($urpm, $medium, hdlist_or_synthesis_for_virtual_medium($medium));
+		}
+	    } else {
+		_parse_synthesis($urpm, $medium, statedir_synthesis($urpm, $medium));
+	    }
+	} else {
+	    _parse_hdlist($urpm, $medium, statedir_hdlist($urpm, $medium));
+	    $medium->{must_build_synthesis} ||= 1;
+	}
+
+    $callback && $callback->('done', $medium->{name});
+}
+
+sub _build_hdlist_synthesis {
+    my ($urpm, $medium) = @_;
+
+    if ($medium->{headers} && !$medium->{modified}) {
+	_build_hdlist_using_rpm_headers($urpm, $medium);
+	#- synthesis needs to be created, since the medium has been built from rpm files.
+	_build_synthesis($urpm,  $medium);
+    } elsif ($medium->{synthesis}) {
+    } else {
+	#- check if the synthesis file can be built.
+	if ($medium->{must_build_synthesis} && !$medium->{modified} && !$medium->{virtual}) {
+	    _build_synthesis($urpm, $medium);
+	}
+    }
+}
+
+sub _update_media__handle_some_flags {
+    my ($urpm, $forcekey, $all) = @_;
+
+    foreach my $medium (grep { !$_->{ignore} } @{$urpm->{media}}) {
+	$forcekey and delete $medium->{'key-ids'};
+
+	if ($medium->{static}) {
+	    #- don't ever update static media
+	    $medium->{modified} = 0;
+	} elsif ($all) {
+	    #- if we're rebuilding all media, mark them as modified (except removable ones)
+	    $medium->{modified} ||= $medium->{url} !~ m!^removable!;
+	}
+    }
+}
+
+#- Update the urpmi database w.r.t. the current configuration.
+#- Takes care of modifications, and tries some tricks to bypass
+#- the recomputation of base files.
+#- Recognized options :
+#-   all         : all medias are being rebuilt
+#-   callback    : UI callback
+#-   forcekey    : force retrieval of pubkey
+#-   force       : try to force rebuilding base files
+#-   force_building_hdlist
+#-   noclean     : keep old files in the header cache directory
+#-   nolock      : don't lock the urpmi database
+#-   nomd5sum    : don't verify MD5SUM of retrieved files
+#-   nopubkey    : don't use rpm pubkeys
+#-   probe_with  : probe synthesis or hdlist (or none)
+#-   quiet       : download hdlists quietly
+sub update_media {
+    my ($urpm, %options) = @_;
+
+    $urpm->{media} or return; # verify that configuration has been read
+
+    $options{nopubkey} ||= $urpm->{options}{nopubkey};
+    #- get gpg-pubkey signature.
+    if (!$options{nopubkey}) {
+	urpm::sys::lock_rpm_db($urpm, 'exclusive');
+	$urpm->{keys} or $urpm->parse_pubkeys(root => $urpm->{root});
+    }
+    #- lock database if allowed.
+    urpm::sys::lock_urpmi_db($urpm, 'exclusive') if !$options{nolock};
+
+    #- examine each medium to see if one of them needs to be updated.
+    #- if this is the case and if not forced, try to use a pre-calculated
+    #- hdlist file, else build it from rpm files.
+    clean($urpm);
+
+    _update_media__handle_some_flags($urpm, $options{forcekey}, $options{all});
+
+    my $clean_cache = !$options{noclean};
+    my $second_pass;
+    foreach my $medium (grep { !$_->{ignore} } @{$urpm->{media}}) {
+	_update_medium_first_pass($urpm, $medium, \$second_pass, \$clean_cache, %options)
+	  or _update_medium_first_pass_failed($urpm, $medium);
+    }
+
+    #- some unresolved provides may force to rebuild all synthesis,
+    #- a second pass will be necessary.
+    if ($second_pass) {
+	$urpm->{log}(N("performing second pass to compute dependencies\n"));
+	$urpm->unresolved_provides_clean;
+    }
+
+    foreach my $medium (grep { !$_->{ignore} } @{$urpm->{media}}) {
+	if ($second_pass) {
+	    #- second pass consists in reading again synthesis or hdlists.
+	    _update_medium_second_pass($urpm, $medium, $options{callback});
+	}
+	_build_hdlist_synthesis($urpm, $medium);
+
+	if ($medium->{really_modified}) {
+	    _get_pubkey_and_descriptions($urpm, $medium, $options{nopubkey});
+	    _read_cachedir_pubkey($urpm, $medium);
+	    generate_medium_names($urpm, $medium);
+	}
+    }
+
+    if ($urpm->{modified}) {
+	if ($options{noclean}) {
+	    #- clean headers cache directory to remove everything that is no longer
+	    #- useful according to the depslist.
+	    urpm::remove_obsolete_headers_in_cache($urpm);
+	}
+	#- write config files in any case
+	write_config($urpm);
+	urpm::download::dump_proxy_config();
+    } elsif ($urpm->{md5sum_modified}) {
+	#- NB: in case of $urpm->{modified}, write_MD5SUM is called in write_config above
+	write_MD5SUM($urpm);
+    }
+
+    $options{nolock} or urpm::sys::unlock_urpmi_db($urpm);
+    $options{nopubkey} or urpm::sys::unlock_rpm_db($urpm);
+}
+
+#- clean params and depslist computation zone.
+sub clean {
+    my ($urpm) = @_;
+
+    $urpm->{depslist} = [];
+    $urpm->{provides} = {};
+
+    foreach (@{$urpm->{media} || []}) {
+	delete $_->{start};
+	delete $_->{end};
+    }
+}
+
+
+#- get the list of packages that should not be upgraded or installed,
+#- typically from the inst.list or skip.list files.
+sub get_packages_list {
+    my ($file, $o_extra) = @_;
+    my $val = [];
+    open(my $f, '<', $file) or return [];
+    foreach (<$f>, split /,/, $o_extra || '') {
+	chomp; s/#.*$//; s/^\s*//; s/\s*$//;
+	next if $_ eq '';
+	push @$val, $_;
+    }
+    $val;
+}
+
+1;
diff --git a/urpm/parallel.pm b/urpm/parallel.pm
index 2e0fc70a..fc8f6020 100644
--- a/urpm/parallel.pm
+++ b/urpm/parallel.pm
@@ -46,8 +46,8 @@ sub resolve_dependencies {
     my $file = "$urpm->{cachedir}/partial/parallel.cz";
     unlink $file;
     foreach (@{$urpm->{media}}) {
-	urpm::is_valid_medium($_) or next;
-	my $f = urpm::statedir_synthesis($urpm, $_);
+	urpm::media::is_valid_medium($_) or next;
+	my $f = urpm::media::statedir_synthesis($urpm, $_);
 	system "cat '$f' >> '$file'";
     }
     #- let each node determine what is requested, according to handler given.