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@jsorrell
Created July 29, 2019 18:16
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Perl script for using dmenu to find the correct command to run a .desktop program
#!/usr/bin/env perl
# vim:ts=4:sw=4:expandtab
#
# © 2012 Michael Stapelberg
#
# No dependencies except for perl ≥ v5.10
#
# Edited from i3-dmenu-desktop for general usage by Jack Sorrell
# July 2019
use strict;
use warnings qw(FATAL utf8);
use Data::Dumper;
use IPC::Open2;
use POSIX qw(locale_h);
use File::Find;
use File::Basename qw(basename);
use File::Temp qw(tempfile);
use Getopt::Long;
use Pod::Usage;
use v5.10;
use utf8;
use open ':encoding(UTF-8)';
binmode STDOUT, ':encoding(UTF-8)';
binmode STDERR, ':encoding(UTF-8)';
# reads in a whole file
sub slurp {
my ($filename) = @_;
my $fh;
if (!open($fh, '<', $filename)) {
warn "Could not open $filename: $!";
return;
}
local $/;
my $result;
eval {
$result = <$fh>;
};
if ($@) {
warn "Could not read $filename: $@";
return;
} else {
return $result;
}
}
my @entry_types;
my $dmenu_cmd = 'dmenu -i';
my $result = GetOptions(
'dmenu=s' => \$dmenu_cmd,
'entry-type=s' => \@entry_types,
'version' => sub {
say "dmenu-desktop 1.5 © 2012 Michael Stapelberg";
exit 0;
},
'help' => sub {
pod2usage(-exitval => 0);
});
die "Could not parse command line options" unless $result;
# Filter entry types and set default type(s) if none selected
my $valid_types = {
name => 1,
command => 1,
filename => 1,
};
@entry_types = grep { exists($valid_types->{$_}) } @entry_types;
@entry_types = ('name', 'command') unless @entry_types;
# ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
# ┃ Convert LC_MESSAGES into an ordered list of suffixes to search for in the ┃
# ┃ .desktop files (e.g. “Name[de_DE@euro]” for LC_MESSAGES=de_DE.UTF-8@euro ┃
# ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
# For details on how the transformation of LC_MESSAGES to a list of keys that
# should be looked up works, refer to “Localized values for keys” of the
# “Desktop Entry Specification”:
# https://standards.freedesktop.org/desktop-entry-spec/latest/ar01s04.html
my $lc_messages = setlocale(LC_MESSAGES);
# Ignore the encoding (e.g. .UTF-8)
$lc_messages =~ s/\.[^@]+//g;
my @suffixes = ($lc_messages);
# _COUNTRY and @MODIFIER are present
if ($lc_messages =~ /_[^@]+@/) {
my $no_modifier = $lc_messages;
$no_modifier =~ s/@.*//g;
push @suffixes, $no_modifier;
my $no_country = $lc_messages;
$no_country =~ s/_[^@]+//g;
push @suffixes, $no_country;
}
# Strip _COUNTRY and @MODIFIER if present
$lc_messages =~ s/[_@].*//g;
push @suffixes, $lc_messages;
# ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
# ┃ Read all .desktop files and store the values in which we are interested. ┃
# ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
my %desktops;
# See https://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html#variables
my $xdg_data_home = $ENV{XDG_DATA_HOME};
$xdg_data_home = $ENV{HOME} . '/.local/share' if
!defined($xdg_data_home) ||
$xdg_data_home eq '' ||
! -d $xdg_data_home;
my $xdg_data_dirs = $ENV{XDG_DATA_DIRS};
$xdg_data_dirs = '/usr/local/share/:/usr/share/' if
!defined($xdg_data_dirs) ||
$xdg_data_dirs eq '';
my @searchdirs = ("$xdg_data_home/applications/");
for my $dir (split(':', $xdg_data_dirs)) {
push @searchdirs, "$dir/applications/";
}
# Cleanup the paths, maybe some application does not cope with double slashes
# (the field code %k is replaced with the .desktop file location).
@searchdirs = map { s,//,/,g; $_ } @searchdirs;
# To avoid errors by File::Find’s find(), only pass existing directories.
@searchdirs = grep { -d $_ } @searchdirs;
find(
{
wanted => sub {
return unless substr($_, -1 * length('.desktop')) eq '.desktop';
my $relative = $File::Find::name;
# + 1 for the trailing /, which is missing in ::topdir.
substr($relative, 0, length($File::Find::topdir) + 1) = '';
# Don’t overwrite files with the same relative path, we search in
# descending order of importance.
return if exists($desktops{$relative});
$desktops{$relative} = $File::Find::name;
},
no_chdir => 1,
},
@searchdirs
);
my %apps;
for my $file (values %desktops) {
my $base = basename($file);
# _ is an invalid character for a key, so we can use it for our own keys.
$apps{$base}->{_Location} = $file;
# Extract all “Name” and “Exec” keys from the [Desktop Entry] group
# and store them in $apps{$base}.
my %names;
my $content = slurp($file);
next unless defined($content);
my @lines = split("\n", $content);
for my $line (@lines) {
my $first = substr($line, 0, 1);
next if $line eq '' || $first eq '#';
next unless ($line eq '[Desktop Entry]' ..
($first eq '[' &&
substr($line, -1) eq ']' &&
$line ne '[Desktop Entry]'));
next if $first eq '[';
my ($key, $value) = ($line =~ /^
(
[A-Za-z0-9-]+ # the spec specifies these as valid key characters
(?:\[[^]]+\])? # possibly, there as a locale suffix
)
\s* = \s* # whitespace around = should be ignored
(.*) # no restrictions on the values
$/x);
if ($key =~ /^Name/) {
$names{$key} = $value;
} elsif ($key eq 'Exec' ||
$key eq 'TryExec' ||
$key eq 'Path' ||
$key eq 'Type') {
$apps{$base}->{$key} = $value;
} elsif ($key eq 'NoDisplay' ||
$key eq 'Hidden' ||
$key eq 'StartupNotify' ||
$key eq 'Terminal') {
# Values of type boolean must either be string true or false,
# see “Possible value types”:
# https://standards.freedesktop.org/desktop-entry-spec/latest/ar01s03.html
$apps{$base}->{$key} = ($value eq 'true');
}
}
for my $suffix (@suffixes) {
next unless exists($names{"Name[$suffix]"});
$apps{$base}->{Name} = $names{"Name[$suffix]"};
last;
}
# Fallback to unlocalized “Name”.
$apps{$base}->{Name} = $names{Name} unless exists($apps{$base}->{Name});
}
# %apps now looks like this:
#
# %apps = {
# 'evince.desktop' => {
# 'Exec' => 'evince %U',
# 'Name' => 'Dokumentenbetrachter',
# '_Location' => '/usr/share/applications/evince.desktop'
# },
# 'gedit.desktop' => {
# 'Exec' => 'gedit %U',
# 'Name' => 'gedit',
# '_Location' => '/usr/share/applications/gedit.desktop'
# }
# };
# ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
# ┃ Turn %apps inside out to provide Name → filename lookup. ┃
# ┃ The Name is what we display in dmenu later. ┃
# ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
my %choices;
for my $app (keys %apps) {
my $name = $apps{$app}->{Name};
# Don’t try to use .desktop files which don’t have Type=application
next if (!exists($apps{$app}->{Type}) ||
$apps{$app}->{Type} ne 'Application');
# Skip broken files (Type=application, but no Exec key).
if (!exists($apps{$app}->{Exec}) ||
$apps{$app}->{Exec} eq '') {
warn 'File ' . $apps{$app}->{_Location} . ' is broken: it contains Type=Application, but no Exec key/value pair.';
next;
}
# Don’t offer apps which have NoDisplay == true or Hidden == true.
# See https://wiki.xfce.org/howto/customize-menu#hide_menu_entries
# for the difference between NoDisplay and Hidden.
next if (exists($apps{$app}->{NoDisplay}) && $apps{$app}->{NoDisplay}) ||
(exists($apps{$app}->{Hidden}) && $apps{$app}->{Hidden});
if (exists($apps{$app}->{TryExec})) {
my $tryexec = $apps{$app}->{TryExec};
if (substr($tryexec, 0, 1) eq '/') {
# Skip if absolute path is not executable.
next unless -x $tryexec;
} else {
# Search in $PATH for the executable.
my $found = 0;
for my $path (split(':', $ENV{PATH})) {
next unless -x "$path/$tryexec";
$found = 1;
last;
}
next unless $found;
}
}
if ((scalar grep { $_ eq 'name' } @entry_types) > 0) {
if (exists($choices{$name})) {
# There are two .desktop files which contain the same “Name” value.
# I’m not sure if that is allowed to happen, but we disambiguate the
# situation by appending “ (2)”, “ (3)”, etc. to the name.
#
# An example of this happening is exo-file-manager.desktop and
# thunar-settings.desktop, both of which contain “Name=File Manager”.
my $inc = 2;
$inc++ while exists($choices{"$name ($inc)"});
$name = "$name ($inc)";
}
$choices{$name} = $app;
next;
}
if ((scalar grep { $_ eq 'command' } @entry_types) > 0) {
my $command = $apps{$app}->{Exec};
# Handle escape sequences (should be done for all string values, but does
# matter here).
my %escapes = (
'\\s' => ' ',
'\\n' => '\n',
'\\t' => '\t',
'\\r' => '\r',
'\\\\' => '\\',
);
$command =~ s/(\\[sntr\\])/$escapes{$1}/go;
# Extract executable
if ($command =~ m/^\s*([^\s\"]+)(?:\s|$)/) {
# No quotes
$command = $1;
} elsif ($command =~ m/^\s*\"([^\"\\]*(?:\\.[^\"\\]*)*)\"(?:\s|$)/) {
# Quoted, remove quotes and fix escaped characters
$command = $1;
$command =~ s/\\([\"\`\$\\])/$1/g;
} else {
# Invalid quotes, fallback to whitespace
($command) = split(' ', $command);
}
# Don’t add “geany” if “Geany” is already present.
my @keys = map { lc } keys %choices;
if (!(scalar grep { $_ eq lc(basename($command)) } @keys) > 0) {
$choices{basename($command)} = $app;
}
next;
}
if ((scalar grep { $_ eq 'filename' } @entry_types) > 0) {
my $filename = basename($app, '.desktop');
# Don’t add “geany” if “Geany” is already present.
my @keys = map { lc } keys %choices;
next if (scalar grep { $_ eq lc($filename) } @keys) > 0;
$choices{$filename} = $app;
}
}
# %choices now looks like this:
#
# %choices = {
# 'Dokumentenbetrachter' => 'evince.desktop',
# 'gedit' => 'gedit.desktop'
# };
# ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
# ┃ Run dmenu to ask the user for their choice ┃
# ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
# open2 will just make dmenu’s STDERR go to our own STDERR.
my ($dmenu_out, $dmenu_in);
my $pid = eval {
open2($dmenu_out, $dmenu_in, $dmenu_cmd);
} or do {
print STDERR "$@";
say STDERR "Running dmenu failed. Is dmenu installed at all? Try running dmenu -v";
exit 1;
};
binmode $dmenu_in, ':encoding(UTF-8)';
binmode $dmenu_out, ':encoding(UTF-8)';
# Feed dmenu the possible choices.
say $dmenu_in $_ for sort keys %choices;
close($dmenu_in);
waitpid($pid, 0);
my $status = ($? >> 8);
# Pass on dmenu’s exit status if there was an error.
exit $status unless $status == 0;
my $choice = <$dmenu_out>;
# dmenu ≥ 4.4 adds a newline after the choice
chomp($choice);
my $app;
# Exact match: the user chose “Avidemux (GTK+)”
if (exists($choices{$choice})) {
$app = $apps{$choices{$choice}};
$choice = '';
} else {
# Not an exact match: the user entered “Avidemux (GTK+) ~/movie.mp4”
for my $possibility (keys %choices) {
next unless substr($choice, 0, length($possibility)) eq $possibility;
$app = $apps{$choices{$possibility}};
substr($choice, 0, length($possibility)) = '';
# Remove whitespace separating the entry and arguments.
$choice =~ s/^\s//g;
last;
}
if (!defined($app)) {
warn "Invalid input: “$choice” does not match any application. Trying to execute nevertheless.";
$app->{Name} = '';
$app->{Exec} = $choice;
# We assume that the app is old and does not support startup
# notifications because it doesn’t ship a desktop file.
$app->{StartupNotify} = 0;
$app->{_Location} = '';
}
}
# ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
# ┃ Make i3 start the chosen application. ┃
# ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
my $name = $app->{Name};
my $exec = $app->{Exec};
my $location = $app->{_Location};
# Quote as described by “The Exec key”:
# https://standards.freedesktop.org/desktop-entry-spec/latest/ar01s06.html
sub quote {
my ($str) = @_;
$str =~ s/("|`|\$|\\)/\\$1/g;
$str = qq|"$str"| if $str ne "";
return $str;
}
$choice = quote($choice);
$location = quote($location);
$name = quote($name);
# Remove deprecated field codes, as the spec dictates.
$exec =~ s/%[dDnNvm]//g;
# Replace filename field codes with the rest of the command line.
# Note that we assume the user uses precisely one file name,
# not multiple file names.
$exec =~ s/%[fF]/$choice/g;
# If the program works with URLs,
# we assume the user provided a URL instead of a filename.
# As per the spec, there must be at most one of %f, %u, %F or %U present.
$exec =~ s/%[uU]/$choice/g;
# The translated name of the application.
$exec =~ s/%c/$name/g;
# XXX: Icons are not implemented. Is the complexity (looking up the path if
# only a name is given) actually worth it?
#$exec =~ s/%i/--icon $icon/g;
$exec =~ s/%i//g;
# location of .desktop file
$exec =~ s/%k/$location/g;
# Literal % characters are represented as %%.
$exec =~ s/%%/%/g;
if (exists($app->{Path}) && $app->{Path} ne '') {
$exec = 'cd ' . quote($app->{Path}) . ' && ' . $exec;
}
my $nosn = '';
my $cmd;
if (exists($app->{Terminal}) && $app->{Terminal}) {
# For applications which specify “Terminal=true” (e.g. htop.desktop),
# we need to create a temporary script that contains the full command line
# as the syntax for starting commands with arguments varies from terminal
# emulator to terminal emulator.
# Then, we launch that script with i3-sensible-terminal.
my ($fh, $filename) = tempfile();
binmode($fh, ':encoding(UTF-8)');
say $fh <<EOT;
#!/bin/sh
rm $filename
exec $exec
EOT
close($fh);
chmod 0755, $filename;
$cmd = qq|i3-sensible-terminal -e "$filename"|;
} else {
$cmd = "$exec";
}
# system('i3-msg', $cmd) == 0 or die "Could not launch i3-msg: $?";
print "$cmd";
=encoding utf-8
=head1 NAME
i3-dmenu-desktop - run .desktop files with dmenu
=head1 SYNOPSIS
i3-dmenu-desktop [--dmenu='dmenu -i'] [--entry-type=name]
=head1 DESCRIPTION
i3-dmenu-desktop is a script which extracts the (localized) name from
application .desktop files, offers the user a choice via dmenu(1) and then
starts the chosen application via i3 (for startup notification support).
The advantage of using .desktop files instead of dmenu_run(1) is that dmenu_run
offers B<all> binaries in your $PATH, including non-interactive utilities like
"sed". Also, .desktop files contain a proper name, information about whether
the application runs in a terminal and whether it supports startup
notifications.
The .desktop files are searched in $XDG_DATA_HOME/applications (by default
$HOME/.local/share/applications) and in the "applications" subdirectory of each
entry of $XDG_DATA_DIRS (by default /usr/local/share/:/usr/share/).
Files with the same name in $XDG_DATA_HOME/applications take precedence over
files in $XDG_DATA_DIRS, so that you can overwrite parts of the system-wide
.desktop files by copying them to your local directory and making changes.
i3-dmenu-desktop displays the "Name" value in the localized version depending
on LC_MESSAGES as specified in the Desktop Entry Specification.
You can pass a filename or URL (%f/%F and %u/%U field codes in the .desktop
file respectively) by appending it to the name of the application. E.g., if you
want to launch "GNU Emacs 24" with the patch /tmp/foobar.txt, you would type
"emacs", press TAB, type " /tmp/foobar.txt" and press ENTER.
.desktop files with Terminal=true are started using i3-sensible-terminal(1).
.desktop files with NoDisplay=true or Hidden=true are skipped.
UTF-8 is supported, of course, but dmenu does not support displaying all
glyphs. E.g., xfce4-terminal.desktop's Name[fi]=Pääte will be displayed just
fine, but not its Name[ru]=Терминал.
=head1 OPTIONS
=over
=item B<--dmenu=command>
Execute command instead of 'dmenu -i'. This option can be used to pass custom
parameters to dmenu, or to make i3-dmenu-desktop start a custom (patched?)
version of dmenu.
=item B<--entry-type=type>
Display the (localized) "Name" (type = name), the command (type = command) or
the (*.desktop) filename (type = filename) in dmenu. This option can be
specified multiple times.
Examples are "GNU Image Manipulation Program" (type = name), "gimp" (type =
command), and "libreoffice-writer" (type = filename).
=back
=head1 VERSION
Version 1.5
=head1 AUTHOR
Michael Stapelberg, C<< <michael at i3wm.org> >>
=head1 LICENSE AND COPYRIGHT
Copyright 2012 Michael Stapelberg.
This program is free software; you can redistribute it and/or modify it
under the terms of the BSD license.
=cut
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