ACC SHELL
| Path : /usr/sbin/ |
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| Current File : //usr/sbin/update-alternatives |
#!/usr/bin/perl --
use strict;
use warnings;
use POSIX qw(:errno_h);
# use Dpkg;
our ($progname) = $0 =~ m#(?:.*/)?([^/]*)#;
our $version = "1.14";
our $admindir = "/var/lib/rpm";
#use Dpkg::Gettext;
eval 'use Locale::gettext';
if ($@) {
eval q{
sub _g {
return shift;
}
sub textdomain {
}
sub ngettext {
if ($_[2] == 1) {
return $_[0];
} else {
return $_[1];
}
}
};
} else {
eval q{
sub _g {
return gettext(shift);
}
};
}
textdomain("rpm");
# Global variables:
my $altdir = '/etc/alternatives';
# FIXME: this should not override the previous assignment.
$admindir = $admindir . '/alternatives';
my $verbosemode = 0;
my $action = ''; # Action to perform (display / install / remove / display / auto / config)
my $mode = 'auto'; # Update mode for alternative (manual / auto)
my $state; # State of alternative:
# expected: alternative with highest priority is the active alternative
# expected-inprogress: busy selecting alternative with highest priority
# unexpected: alternative another alternative is active / error during readlink
# nonexistent: alternative-symlink does not exist
my %versionnum; # Map from currently available versions into @versions and @priorities
my @versions; # List of available versions for alternative
my @priorities; # Map from @version-index to priority
my $best;
my $bestpri;
my $bestnum;
my $link; # Link we are working with
my $linkname;
my $alink; # Alternative we are managing (ie the symlink we're making/removing) (install only)
my $name; # Name of the alternative (the symlink) we are processing
my $apath; # Path of alternative we are offering
my $apriority; # Priority of link (only when we are installing an alternative)
my %aslavelink;
my %aslavepath;
my %aslavelinkcount;
my $slink;
my $sname;
my $spath;
my @slavenames; # List with names of slavelinks
my %slavenum; # Map from name of slavelink to slave-index (into @slavelinks)
my @slavelinks; # List of slavelinks (indexed by slave-index)
my %slavepath; # Map from (@version-index,slavename) to slave-path
my %slavelinkcount;
sub version {
printf _g("SUSE %s version %s.\n"), $progname, $version;
printf _g("
Copyright (C) 1995 Ian Jackson.
Copyright (C) 2000-2002 Wichert Akkerman.");
printf _g("
This is free software; see the GNU General Public Licence version 2 or
later for copying conditions. There is NO warranty.
");
}
sub usage {
printf _g(
"Usage: %s [<option> ...] <command>
Commands:
--install <link> <name> <path> <priority>
[--slave <link> <name> <path>] ...
add a group of alternatives to the system.
--remove <name> <path> remove <path> from the <name> group alternative.
--remove-all <name> remove <name> group from the alternatives system.
--auto <name> switch the master link <name> to automatic mode.
--display <name> display information about the <name> group.
--list <name> display all targets of the <name> group.
--config <name> show alternatives for the <name> group and ask the
user to select which one to use.
--set <name> <path> set <path> as alternative for <name>.
--all call --config on all alternatives.
<link> is the symlink pointing to %s/<name>.
(e.g. /usr/bin/pager)
<name> is the master name for this link group.
(e.g. pager)
<path> is the location of one of the alternative target files.
(e.g. /usr/bin/less)
<priority> is an integer; options with higher numbers have higher priority in
automatic mode.
Options:
--altdir <directory> change the alternatives directory.
--admindir <directory> change the administrative directory.
--verbose verbose operation, more output.
--quiet quiet operation, minimal output.
--help show this help message.
--version show the version.
"), $progname, $altdir;
}
sub quit
{
printf STDERR "%s: %s\n", $progname, "@_";
exit(2);
}
sub badusage
{
printf STDERR "%s: %s\n\n", $progname, "@_";
&usage;
exit(2);
}
sub read_link_group
{
if (open(AF, "$admindir/$name")) {
$mode = gl("update_mode");
$mode eq 'auto' || $mode eq 'manual' || badfmt(_g("invalid update mode"));
$link = gl("link");
while (($sname = gl("sname")) ne '') {
push(@slavenames, $sname);
defined($slavenum{$sname}) && badfmt(sprintf(_g("duplicate slave %s"), $sname));
$slavenum{$sname} = $#slavenames;
$slink = gl("slink");
$slink eq $link && badfmt(sprintf(_g("slave link same as main link %s"), $link));
$slavelinkcount{$slink}++ && badfmt(sprintf(_g("duplicate slave link %s"), $slink));
push(@slavelinks, $slink);
}
while (($version = gl("version")) ne '') {
defined($versionnum{$version}) && badfmt(sprintf(_g("duplicate path %s"), $version));
if (-r $version || $mode eq 'remove' && $apath eq $version) {
push(@versions, $version);
my $i;
$versionnum{$version} = $i = $#versions;
my $priority = gl("priority");
$priority =~ m/^[-+]?\d+$/ || badfmt(sprintf(_g("priority %s %s"), $version, $priority));
$priorities[$i] = $priority;
for (my $j = 0; $j <= $#slavenames; $j++) {
$slavepath{$i,$j} = gl("spath");
}
} else {
# File not found - remove
pr(sprintf(_g("Alternative for %s points to %s - which wasn't found. Removing from list of alternatives."), $name, $version))
if $verbosemode > 0;
gl("priority");
for (my $j = 0; $j <= $#slavenames; $j++) {
gl("spath");
}
}
}
close(AF);
return 0;
} elsif ($! != ENOENT) {
quit(sprintf(_g("unable to open %s: %s"), "$admindir/$name", $!));
} elsif ($! == ENOENT) {
return 1;
}
}
sub fill_missing_slavepaths()
{
for (my $j = 0; $j <= $#slavenames; $j++) {
for (my $i = 0; $i <= $#versions; $i++) {
$slavepath{$i,$j} ||= '';
}
}
}
sub find_best_version
{
$best = '';
for (my $i = 0; $i <= $#versions; $i++) {
if ($best eq '' || $priorities[$i] > $bestpri) {
$best = $versions[$i];
$bestpri = $priorities[$i];
$bestnum = $i;
}
}
}
sub display_link_group
{
pr(sprintf(_g("%s - status is %s."), $name, $mode));
$linkname = readlink("$altdir/$name");
if (defined($linkname)) {
pr(sprintf(_g(" link currently points to %s"), $linkname));
} elsif ($! == ENOENT) {
pr(_g(" link currently absent"));
} else {
pr(sprintf(_g(" link unreadable - %s"), $!));
}
for (my $i = 0; $i <= $#versions; $i++) {
pr(sprintf(_g("%s - priority %s"), $versions[$i], $priorities[$i]));
for (my $j = 0; $j <= $#slavenames; $j++) {
my $tspath = $slavepath{$i, $j};
next unless length($tspath);
pr(sprintf(_g(" slave %s: %s"), $slavenames[$j], $tspath));
}
}
if ($best eq '') {
pr(_g("No versions available."));
} else {
pr(sprintf(_g("Current \`best' version is %s."), $best));
}
}
sub list_link_group
{
for (my $i = 0; $i <= $#versions; $i++) {
pr("$versions[$i]");
}
}
sub checked_alternative($$$)
{
my ($name, $link, $path) = @_;
$linkname = readlink($link);
if (!defined($linkname) && $! != ENOENT) {
pr(sprintf(_g("warning: %s is supposed to be a symlink to %s, \n".
"or nonexistent; however, readlink failed: %s"),
$link, "$altdir/$name", $!))
if $verbosemode > 0;
} elsif (!defined($linkname) ||
(defined($linkname) && $linkname ne "$altdir/$name")) {
checked_rm("$link.rpm-tmp");
checked_symlink("$altdir/$name", "$link.rpm-tmp");
checked_mv("$link.rpm-tmp", $link);
}
$linkname = readlink("$altdir/$name");
if (defined($linkname) && $linkname eq $path) {
pr(sprintf(_g("Leaving %s (%s) pointing to %s."), $name, $link, $path))
if $verbosemode > 0;
} else {
pr(sprintf(_g("Updating %s (%s) to point to %s."), $name, $link, $path))
if $verbosemode > 0;
}
}
sub set_links($$)
{
my ($spath, $preferred) = (@_);
printf STDOUT _g("Using '%s' to provide '%s'.") . "\n", $spath, $name;
checked_symlink("$spath","$altdir/$name.rpm-tmp");
checked_mv("$altdir/$name.rpm-tmp", "$altdir/$name");
# Link slaves...
for (my $slnum = 0; $slnum < @slavenames; $slnum++) {
my $slave = $slavenames[$slnum];
if ($slavepath{$preferred, $slnum} ne '') {
checked_alternative($slave, $slavelinks[$slnum],
$slavepath{$preferred, $slnum});
checked_symlink($slavepath{$preferred, $slnum},
"$altdir/$slave.rpm-tmp");
checked_mv("$altdir/$slave.rpm-tmp", "$altdir/$slave");
} else {
pr(sprintf(_g("Removing %s (%s), not appropriate with %s."), $slave,
$slavelinks[$slnum], $versions[$preferred]))
if $verbosemode > 0;
checked_rm("$altdir/$slave");
}
}
}
sub check_many_actions()
{
return unless $action;
badusage(sprintf(_g("two commands specified: %s and --%s"), $_, $action));
}
sub checked_rm($)
{
my ($f) = @_;
unlink($f) || $! == ENOENT ||
quit(sprintf(_g("unable to remove %s: %s"), $f, $!));
}
#
# Main program
#
$| = 1;
while (@ARGV) {
$_= shift(@ARGV);
last if m/^--$/;
if (!m/^--/) {
&quit(sprintf(_g("unknown argument \`%s'"), $_));
} elsif (m/^--help$/) {
&usage; exit(0);
} elsif (m/^--version$/) {
&version; exit(0);
} elsif (m/^--verbose$/) {
$verbosemode= +1;
} elsif (m/^--quiet$/) {
$verbosemode= -1;
} elsif (m/^--install$/) {
check_many_actions();
@ARGV >= 4 || &badusage(_g("--install needs <link> <name> <path> <priority>"));
($alink,$name,$apath,$apriority,@ARGV) = @ARGV;
$apriority =~ m/^[-+]?\d+/ || &badusage(_g("priority must be an integer"));
$action = 'install';
} elsif (m/^--(remove|set)$/) {
check_many_actions();
@ARGV >= 2 || &badusage(sprintf(_g("--%s needs <name> <path>"), $1));
($name,$apath,@ARGV) = @ARGV;
$action = $1;
} elsif (m/^--(display|auto|config|list|remove-all)$/) {
check_many_actions();
@ARGV || &badusage(sprintf(_g("--%s needs <name>"), $1));
$action = $1;
$name= shift(@ARGV);
} elsif (m/^--slave$/) {
@ARGV >= 3 || &badusage(_g("--slave needs <link> <name> <path>"));
($slink,$sname,$spath,@ARGV) = @ARGV;
defined($aslavelink{$sname}) && &badusage(sprintf(_g("slave name %s duplicated"), $sname));
$aslavelinkcount{$slink}++ && &badusage(sprintf(_g("slave link %s duplicated"), $slink));
$aslavelink{$sname}= $slink;
$aslavepath{$sname}= $spath;
} elsif (m/^--altdir$/) {
@ARGV || &badusage(sprintf(_g("--%s needs a <directory> argument"), "altdir"));
$altdir= shift(@ARGV);
} elsif (m/^--admindir$/) {
@ARGV || &badusage(sprintf(_g("--%s needs a <directory> argument"), "admindir"));
$admindir= shift(@ARGV);
} elsif (m/^--all$/) {
$action = 'all';
} else {
&badusage(sprintf(_g("unknown option \`%s'"), $_));
}
}
defined($name) && defined($aslavelink{$name}) &&
badusage(sprintf(_g("name %s is both primary and slave"), $name));
defined($alink) && $aslavelinkcount{$alink} &&
badusage(sprintf(_g("link %s is both primary and slave"), $alink));
$action ||
badusage(_g("need --display, --config, --set, --install, --remove, --all, --remove-all or --auto"));
$action eq 'install' || !%aslavelink ||
badusage(_g("--slave only allowed with --install"));
if ($action eq 'all') {
&config_all();
exit 0;
}
if (read_link_group()) {
if ($action eq 'remove') {
# FIXME: Be consistent for now with the case when we try to remove a
# non-existing path from an existing link group file.
exit 0;
} elsif ($action ne 'install') {
pr(sprintf(_g("No alternatives for %s."), $name));
exit 1;
}
}
if ($action eq 'display') {
find_best_version();
display_link_group();
exit 0;
}
if ($action eq 'list') {
list_link_group();
exit 0;
}
find_best_version();
if ($action eq 'config') {
config_alternatives($name);
}
if ($action eq 'set') {
set_alternatives($name);
}
if (defined($linkname= readlink("$altdir/$name"))) {
if (! -e $linkname) { # handle broken links as nonexistent
$state= 'nonexistent';
} elsif ($linkname eq $best) {
$state= 'expected';
} elsif (defined(readlink("$altdir/$name.rpm-tmp"))) {
$state= 'expected-inprogress';
} else {
$state= 'unexpected';
}
} elsif ($! == &ENOENT) {
$state= 'nonexistent';
} else {
$state= 'unexpected';
}
# Possible values for:
# $mode manual, auto
# $state expected, expected-inprogress, unexpected, nonexistent
# $action auto, install, remove, remove-all
# all independent
if ($action eq 'auto') {
&pr(sprintf(_g("Setting up automatic selection of %s."), $name))
if $verbosemode > 0;
checked_rm("$altdir/$name.rpm-tmp");
checked_rm("$altdir/$name");
$state= 'nonexistent';
$mode = 'auto';
}
# $mode manual, auto
# $state expected, expected-inprogress, unexpected, nonexistent
# $action auto, install, remove
# action=auto <=> state=nonexistent
if ($state eq 'unexpected' && $mode eq 'auto') {
&pr(sprintf(_g("%s has been changed (manually or by a script).\n".
"Switching to manual updates only."), "$altdir/$name"))
if $verbosemode > 0;
$mode = 'manual';
}
# $mode manual, auto
# $state expected, expected-inprogress, unexpected, nonexistent
# $action auto, install, remove
# action=auto <=> state=nonexistent
# state=unexpected => mode=manual
&pr(sprintf(_g("Checking available versions of %s, updating links in %s ...\n".
"(You may modify the symlinks there yourself if desired - see \`man ln'.)"), $name, $altdir))
if $verbosemode > 0;
if ($action eq 'install') {
if (defined($link) && $link ne $alink) {
&pr(sprintf(_g("Renaming %s link from %s to %s."), $name, $link, $alink))
if $verbosemode > 0;
rename_mv($link,$alink) || $! == &ENOENT ||
&quit(sprintf(_g("unable to rename %s to %s: %s"), $link, $alink, $!));
}
$link= $alink;
my $i;
if (!defined($i= $versionnum{$apath})) {
push(@versions,$apath);
$versionnum{$apath}= $i= $#versions;
}
$priorities[$i]= $apriority;
for $sname (keys %aslavelink) {
my $j;
if (!defined($j= $slavenum{$sname})) {
push(@slavenames,$sname);
$slavenum{$sname}= $j= $#slavenames;
}
my $oldslavelink = $slavelinks[$j];
my $newslavelink = $aslavelink{$sname};
$slavelinkcount{$oldslavelink}-- if defined($oldslavelink);
$slavelinkcount{$newslavelink}++ &&
&quit(sprintf(_g("slave link name %s duplicated"), $newslavelink));
if (defined($oldslavelink) && $newslavelink ne $oldslavelink) {
&pr(sprintf(_g("Renaming %s slave link from %s to %s."), $sname, $oldslavelink, $newslavelink))
if $verbosemode > 0;
rename_mv($oldslavelink,$newslavelink) || $! == &ENOENT ||
&quit(sprintf(_g("unable to rename %s to %s: %s"), $oldslavelink, $newslavelink, $!));
}
$slavelinks[$j]= $newslavelink;
}
for (my $j = 0; $j <= $#slavenames; $j++) {
$slavepath{$i,$j}= $aslavepath{$slavenames[$j]};
}
fill_missing_slavepaths();
}
if ($action eq 'remove') {
my $hits = 0;
if ($mode eq "manual" and $state ne "expected" and (map { $hits += $apath eq $_ } @versions) and $hits and $linkname eq $apath) {
&pr(_g("Removing manually selected alternative - switching to auto mode"));
$mode = "auto";
}
if (defined(my $i = $versionnum{$apath})) {
my $k = $#versions;
$versionnum{$versions[$k]}= $i;
delete $versionnum{$versions[$i]};
$versions[$i]= $versions[$k]; $#versions--;
$priorities[$i]= $priorities[$k]; $#priorities--;
for (my $j = 0; $j <= $#slavenames; $j++) {
$slavepath{$i,$j}= $slavepath{$k,$j};
delete $slavepath{$k,$j};
}
} else {
&pr(sprintf(_g("Alternative %s for %s not registered, not removing."), $apath, $name))
if $verbosemode > 0;
}
}
if ($action eq 'remove-all') {
$mode = "auto";
my $k = $#versions;
for (my $i = 0; $i <= $#versions; $i++) {
$k--;
delete $versionnum{$versions[$i]};
$#priorities--;
for (my $j = 0; $j <= $#slavenames; $j++) {
$slavepath{$i,$j}= $slavepath{$k,$j};
delete $slavepath{$k,$j};
}
}
$#versions=$k;
}
for (my $j = 0; $j <= $#slavenames; $j++) {
my $i;
for ($i = 0; $i <= $#versions; $i++) {
last if $slavepath{$i,$j} ne '';
}
if ($i > $#versions) {
&pr(sprintf(_g("Discarding obsolete slave link %s (%s)."), $slavenames[$j], $slavelinks[$j]))
if $verbosemode > 0;
checked_rm("$altdir/$slavenames[$j]");
checked_rm($slavelinks[$j]);
my $k = $#slavenames;
$slavenum{$slavenames[$k]}= $j;
delete $slavenum{$slavenames[$j]};
$slavelinkcount{$slavelinks[$j]}--;
$slavenames[$j]= $slavenames[$k]; $#slavenames--;
$slavelinks[$j]= $slavelinks[$k]; $#slavelinks--;
for (my $i = 0; $i <= $#versions; $i++) {
$slavepath{$i,$j}= $slavepath{$i,$k};
delete $slavepath{$i,$k};
}
$j--;
}
}
if ($mode eq 'manual') {
&pr(sprintf(_g("Automatic updates of %s are disabled, leaving it alone."), "$altdir/$name"))
if $verbosemode > 0;
&pr(sprintf(_g("To return to automatic updates use \`update-alternatives --auto %s'."), $name))
if $verbosemode > 0;
} else {
if ($state eq 'expected-inprogress') {
&pr(sprintf(_g("Recovering from previous failed update of %s ..."), $name));
checked_mv("$altdir/$name.rpm-tmp", "$altdir/$name");
$state= 'expected';
}
}
# $mode manual, auto
# $state expected, expected-inprogress, unexpected, nonexistent
# $action auto, install, remove
# action=auto <=> state=nonexistent
# state=unexpected => mode=manual
# mode=auto => state!=expected-inprogress && state!=unexpected
open(AF,">$admindir/$name.rpm-new") ||
&quit(sprintf(_g("unable to open %s for write: %s"), "$admindir/$name.rpm-new", $!));
paf($mode);
&paf($link);
for (my $j = 0; $j <= $#slavenames; $j++) {
&paf($slavenames[$j]);
&paf($slavelinks[$j]);
}
find_best_version();
&paf('');
for (my $i = 0; $i <= $#versions; $i++) {
&paf($versions[$i]);
&paf($priorities[$i]);
for (my $j = 0; $j <= $#slavenames; $j++) {
&paf($slavepath{$i,$j});
}
}
&paf('');
close(AF) || &quit(sprintf(_g("unable to close %s: %s"), "$admindir/$name.rpm-new", $!));
if ($mode eq 'auto') {
if ($best eq '') {
&pr(sprintf(_g("Last package providing %s (%s) removed, deleting it."), $name, $link))
if $verbosemode > 0;
checked_rm("$altdir/$name");
checked_rm("$link");
checked_rm("$admindir/$name.rpm-new");
checked_rm("$admindir/$name");
exit(0);
} else {
checked_alternative($name, $link, $best);
checked_rm("$altdir/$name.rpm-tmp");
symlink($best,"$altdir/$name.rpm-tmp");
}
}
checked_mv("$admindir/$name.rpm-new", "$admindir/$name");
if ($mode eq 'auto') {
checked_mv("$altdir/$name.rpm-tmp", "$altdir/$name");
for (my $j = 0; $j <= $#slavenames; $j++) {
$sname= $slavenames[$j];
$slink= $slavelinks[$j];
$spath= $slavepath{$bestnum,$j};
checked_rm("$altdir/$sname.rpm-tmp");
if ($spath eq '') {
&pr(sprintf(_g("Removing %s (%s), not appropriate with %s."), $sname, $slink, $best))
if $verbosemode > 0;
checked_rm("$altdir/$sname");
checked_rm("$slink");
} else {
checked_alternative($sname, $slink, $spath);
checked_symlink("$spath", "$altdir/$sname.rpm-tmp");
checked_mv("$altdir/$sname.rpm-tmp", "$altdir/$sname");
}
}
}
sub config_message {
if ($#versions < 0) {
print "\n";
printf _g("There is no program which provides %s.\n".
"Nothing to configure.\n"), $name;
return -1;
}
if ($#versions == 0) {
print "\n";
printf _g("There is only 1 program which provides %s\n".
"(%s). Nothing to configure.\n"), $name, $versions[0];
return -1;
}
print STDOUT "\n";
printf(STDOUT _g("There are %s alternatives which provide \`%s'.\n\n".
" Selection Alternative\n".
"-----------------------------------------------\n"),
$#versions+1, $name);
for (my $i = 0; $i <= $#versions; $i++) {
printf(STDOUT "%s%s %8s %s\n",
(readlink("$altdir/$name") eq $versions[$i]) ? '*' : ' ',
($best eq $versions[$i]) ? '+' : ' ',
$i+1, $versions[$i]);
}
printf(STDOUT "\n"._g("Press enter to keep the default[*], or type selection number: "));
return 0;
}
sub config_alternatives {
my $preferred;
do {
return if config_message() < 0;
$preferred=<STDIN>;
chop($preferred);
} until $preferred eq '' || $preferred>=1 && $preferred<=$#versions+1 &&
($preferred =~ m/[0-9]*/);
if ($preferred ne '') {
$mode = "manual";
$preferred--;
my $spath = $versions[$preferred];
set_links($spath, $preferred);
}
}
sub set_alternatives {
$mode = "manual";
# Get prefered number
my $preferred = -1;
for (my $i = 0; $i <= $#versions; $i++) {
if($versions[$i] eq $apath) {
$preferred = $i;
last;
}
}
if($preferred == -1){
&quit(sprintf(_g("Cannot find alternative `%s'."), $apath)."\n")
}
set_links($apath, $preferred);
}
sub pr { print(STDOUT "@_\n") || &quit(sprintf(_g("error writing stdout: %s"), $!)); }
sub paf {
$_[0] =~ m/\n/ && &quit(sprintf(_g("newlines prohibited in update-alternatives files (%s)"), $_[0]));
print(AF "$_[0]\n") || &quit(sprintf(_g("error writing stdout: %s"), $!));
}
sub gl {
$!=0; $_= <AF>;
defined($_) || quit(sprintf(_g("error or eof reading %s for %s (%s)"),
"$admindir/$name", $_[0], $!));
s/\n$// || &badfmt(sprintf(_g("missing newline after %s"), $_[0]));
$_;
}
sub badfmt {
&quit(sprintf(_g("internal error: %s corrupt: %s"), "$admindir/$name", $_[0]));
}
sub rename_mv {
return (rename($_[0], $_[1]) || (system(("mv", $_[0], $_[1])) == 0));
}
sub checked_symlink {
my ($filename, $linkname) = @_;
symlink($filename, $linkname) ||
&quit(sprintf(_g("unable to make %s a symlink to %s: %s"), $linkname, $filename, $!));
}
sub checked_mv {
my ($source, $dest) = @_;
rename_mv($source, $dest) ||
&quit(sprintf(_g("unable to install %s as %s: %s"), $source, $dest, $!));
}
sub config_all {
opendir ADMINDIR, $admindir or die sprintf(_g("Serious problem: %s"), $!);
my @filenames = grep !/^\.\.?$/, readdir ADMINDIR;
close ADMINDIR;
foreach my $name (@filenames) {
system "$0 --config $name";
exit $? if $?;
}
}
exit(0);
# vim: nowrap ts=8 sw=4
ACC SHELL 2018