#!/usr/bin/perl -w
-# Copyright © 2001, 2002 Jamie Zawinski <jwz@jwz.org>.
+# Copyright © 2001-2013 Jamie Zawinski <jwz@jwz.org>.
#
# Permission to use, copy, modify, distribute, and sell this software and its
# documentation for any purpose is hereby granted without fee, provided that
# software for any purpose. It is provided "as is" without express or
# implied warranty.
#
-# This program attempts to locate a random image from the specified directory,
-# and load it on to the root window, using some other program that can decode
-# image files. (It attempts to find such a program.)
+# This program chooses a random file from under the given directory, and
+# prints its name. The file will be an image file whose dimensions are
+# larger than a certain minimum size.
#
-# The various xscreensaver hacks that manipulate images ("slidescreen",
-# "jigsaw", etc.) get the image to manipulate by running the
-# "xscreensaver-getimage" program.
+# If the directory is a URL, it is assumed to be an RSS or Atom feed.
+# The images from that feed will be downloaded, cached, and selected from
+# at random. The feed will be re-polled periodically, as needed.
#
-# "xscreensaver-getimage" will invoke this program, depending on the
-# value of the "chooseRandomImages" and "imageDirectory" settings in
-# the ~/.xscreensaver file (or /usr/lib/X11/app-defaults/XScreenSaver).
+# The various xscreensaver hacks that manipulate images ("jigsaw", etc.) get
+# the image to manipulate by running the "xscreensaver-getimage" program.
+#
+# Under X11, the "xscreensaver-getimage" program invokes this script,
+# depending on the value of the "chooseRandomImages" and "imageDirectory"
+# settings in the ~/.xscreensaver file (or .../app-defaults/XScreenSaver).
+# The screen savers invoke "xscreensaver-getimage" via utils/grabclient.c,
+# which then invokes this script.
+#
+# Under Cocoa, this script lives inside the .saver bundle, and is invoked
+# directly from utils/grabclient.c.
#
# Created: 12-Apr-01.
require 5;
-use diagnostics;
+#use diagnostics; # Fails on some MacOS 10.5 systems
use strict;
use POSIX;
use Fcntl;
-# use Fcntl ':mode'; # Perl 5.6ism?
-use POSIX ':fcntl_h'; # more portable?
+use Fcntl ':flock'; # import LOCK_* constants
+
+use POSIX ':fcntl_h'; # S_ISDIR was here in Perl 5.6
+import Fcntl ':mode' unless defined &S_ISUID; # but it is here in Perl 5.8
+ # but in Perl 5.10, both of these load, and cause errors!
+ # So we have to check for S_ISUID instead of S_ISDIR? WTF?
+
+use bytes; # Larry can take Unicode and shove it up his ass sideways.
+ # Perl 5.8.0 causes us to start getting incomprehensible
+ # errors about UTF-8 all over the place without this.
+
+use Digest::MD5 qw(md5_base64);
+
+# Some Linux systems don't install LWP by default!
+# Only error out if we're actually loading a URL instead of local data.
+BEGIN { eval 'use LWP::Simple;' }
my $progname = $0; $progname =~ s@.*/@@g;
-my $version = q{ $Revision: 1.10 $ }; $version =~ s/^[^0-9]+([0-9.]+).*$/$1/;
+my $version = q{ $Revision: 1.37 $ }; $version =~ s/^[^0-9]+([0-9.]+).*$/$1/;
my $verbose = 0;
-# These are programs that can be used to put an image file on the root
-# window (including virtual root windows.) The first one of these programs
-# that exists on $PATH will be used (with the file name as the last arg.)
+# Whether to use MacOS X's Spotlight to generate the list of files.
+# When set to -1, uses Spotlight if "mdfind" exists.
#
-# If you add other programs to this list, please let me know!
+# (In my experience, this isn't actually any faster, and might not find
+# everything if your Spotlight index is out of date, which happens often.)
#
-my @programs = (
- "chbg -once -xscreensaver -max_grow 4 -max_size 100",
- "xv -root -quit -viewonly -maxpect +noresetroot -quick24 -rmode 5" .
- " -rfg black -rbg black",
- "xli -quiet -fullscreen -onroot -center -border black",
- "xloadimage -quiet -fullscreen -onroot -center -border black",
+my $use_spotlight_p = 0;
-# this lame program wasn't built with vroot.h:
-# "xsri -scale -keep-aspect -center-horizontal -center-vertical",
-);
+# Whether to cache the results of the last run.
+#
+my $cache_p = 1;
-sub pick_displayer {
- my @names = ();
+# Regenerate the cache if it is older than this many seconds.
+#
+my $cache_max_age = 60 * 60 * 3; # 3 hours
- foreach my $cmd (@programs) {
- $_ = $cmd;
- my ($name) = m/^([^ ]+)/;
- push @names, "\"$name\"";
- print STDERR "$progname: looking for $name...\n" if ($verbose > 2);
- foreach my $dir (split (/:/, $ENV{PATH})) {
- print STDERR "$progname: checking $dir/$name\n" if ($verbose > 3);
- return $cmd if (-x "$dir/$name");
- }
- }
+# Re-poll RSS/Atom feeds when local copy is older than this many seconds.
+#
+my $feed_max_age = $cache_max_age;
- $names[$#names] = "or " . $names[$#names];
- printf STDERR "$progname: none of: " . join (", ", @names) .
- " were found on \$PATH.\n";
- exit 1;
-}
+
+# This matches files that we are allowed to use as images (case-insensitive.)
+# Anything not matching this is ignored. This is so you can point your
+# imageDirectory at directory trees that have things other than images in
+# them, but it assumes that you gave your images sensible file extensions.
+#
+my @good_extensions = ('jpg', 'jpeg', 'pjpeg', 'pjpg', 'png', 'gif',
+ 'tif', 'tiff', 'xbm', 'xpm');
+my $good_file_re = '\.(' . join("|", @good_extensions) . ')$';
+
+# This matches file extensions that might occur in an image directory,
+# and that are never used in the name of a subdirectory. This is an
+# optimization that prevents us from having to stat() those files to
+# tell whether they are directories or not. (It speeds things up a
+# lot. Don't give your directories stupid names.)
+#
+my @nondir_extensions = ('ai', 'bmp', 'bz2', 'cr2', 'crw', 'db',
+ 'dmg', 'eps', 'gz', 'hqx', 'htm', 'html', 'icns', 'ilbm', 'mov',
+ 'nef', 'pbm', 'pdf', 'pl', 'ppm', 'ps', 'psd', 'sea', 'sh', 'shtml',
+ 'tar', 'tgz', 'thb', 'txt', 'xcf', 'xmp', 'Z', 'zip' );
+my $nondir_re = '\.(' . join("|", @nondir_extensions) . ')$';
-my @all_files = ();
-my %seen_inodes;
+# JPEG, GIF, and PNG files that are are smaller than this are rejected:
+# this is so that you can use an image directory that contains both big
+# images and thumbnails, and have it only select the big versions.
+#
+my $min_image_width = 255;
+my $min_image_height = 255;
+
+my @all_files = (); # list of "good" files we've collected
+my %seen_inodes; # for breaking recursive symlink loops
-sub find_all_files {
+# For diagnostic messages:
+#
+my $dir_count = 1; # number of directories seen
+my $stat_count = 0; # number of files/dirs stat'ed
+my $skip_count_unstat = 0; # number of files skipped without stat'ing
+my $skip_count_stat = 0; # number of files skipped after stat
+
+sub find_all_files($);
+sub find_all_files($) {
my ($dir) = @_;
- print STDERR "$progname: reading dir $dir/...\n" if ($verbose > 2);
+ print STDERR "$progname: + reading dir $dir/...\n" if ($verbose > 1);
- local *DIR;
- if (! opendir (DIR, $dir)) {
- print STDERR "$progname: couldn't open $dir: $!\n";
+ my $dd;
+ if (! opendir ($dd, $dir)) {
+ print STDERR "$progname: couldn't open $dir: $!\n" if ($verbose);
return;
}
- my @files = readdir (DIR);
- closedir (DIR);
+ my @files = readdir ($dd);
+ closedir ($dd);
my @dirs = ();
foreach my $file (@files) {
- next if ($file =~ m/^\./); # ignore dot files
- next if ($file =~ m/[~%\#]$/); # ignore backup files
- next if ($file =~ m/\.(BAK|bak|tmp|orig|rej|rpmsave)$/);
- next if ($file eq "core");
+ next if ($file =~ m/^\./); # silently ignore dot files/dirs
+
+ if ($file =~ m/[~%\#]$/) { # ignore backup files (and dirs...)
+ $skip_count_unstat++;
+ print STDERR "$progname: - skip file $file\n" if ($verbose > 1);
+ }
$file = "$dir/$file";
- my @st = stat($file);
- my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
- $atime,$mtime,$ctime,$blksize,$blocks) = @st;
-
- if ($#st == -1) {
- if ($verbose) {
- my $ll = readlink $file;
- if (defined ($ll)) {
- print STDERR "$progname: dangling symlink: $file -> $ll\n";
- } else {
- print STDERR "$progname: unreadable: $file\n";
+
+ if ($file =~ m/$good_file_re/io) {
+ #
+ # Assume that files ending in .jpg exist and are not directories.
+ #
+ push @all_files, $file;
+ print STDERR "$progname: - found file $file\n" if ($verbose > 1);
+
+ } elsif ($file =~ m/$nondir_re/io) {
+ #
+ # Assume that files ending in .html are not directories.
+ #
+ $skip_count_unstat++;
+ print STDERR "$progname: -- skip file $file\n" if ($verbose > 1);
+
+ } else {
+ #
+ # Now we need to stat the file to see if it's a subdirectory.
+ #
+ # Note: we could use the trick of checking "nlinks" on the parent
+ # directory to see if this directory contains any subdirectories,
+ # but that would exclude any symlinks to directories.
+ #
+ my @st = stat($file);
+ my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
+ $atime,$mtime,$ctime,$blksize,$blocks) = @st;
+
+ $stat_count++;
+
+ if ($#st == -1) {
+ if ($verbose) {
+ my $ll = readlink $file;
+ if (defined ($ll)) {
+ print STDERR "$progname: + dangling symlink: $file -> $ll\n";
+ } else {
+ print STDERR "$progname: + unreadable: $file\n";
+ }
}
+ next;
}
- next;
- }
- next if ($seen_inodes{$ino}); # break symlink loops
- $seen_inodes{$ino} = 1;
+ next if ($seen_inodes{"$dev:$ino"}); # break symlink loops
+ $seen_inodes{"$dev:$ino"} = 1;
- if (S_ISDIR($mode)) {
- push @dirs, $file;
- print STDERR "$progname: found dir $file\n" if ($verbose > 2);
- } elsif (S_ISREG($mode) || S_ISLNK($mode)) {
- push @all_files, $file;
- print STDERR "$progname: found file $file\n" if ($verbose > 2);
- } elsif ($verbose > 2) {
- print STDERR "$progname: nonreg $file\n";
+ if (S_ISDIR($mode)) {
+ push @dirs, $file;
+ $dir_count++;
+ print STDERR "$progname: + found dir $file\n" if ($verbose > 1);
+
+ } else {
+ $skip_count_stat++;
+ print STDERR "$progname: + skip file $file\n" if ($verbose > 1);
+ }
}
}
}
-sub find_random_file {
+sub spotlight_all_files($) {
my ($dir) = @_;
- $dir =~ s@/+$@@g;
+ my @terms = ();
+ # "public.image" matches all (indexed) images, including Photoshop, etc.
+# push @terms, "kMDItemContentTypeTree == 'public.image'";
+ foreach (@good_extensions) {
+
+ # kMDItemFSName hits the file system every time: much worse than "find".
+# push @terms, "kMDItemFSName == '*.$_'";
+
+ # kMDItemDisplayName matches against the name in the Spotlight index,
+ # but won't find files that (for whatever reason) didn't get indexed.
+ push @terms, "kMDItemDisplayName == '*.$_'";
+ }
+
+ $dir =~ s@([^-_/a-z\d.,])@\\$1@gsi; # quote for sh
+ my $cmd = "mdfind -onlyin $dir \"" . join (' || ', @terms) . "\"";
+
+ print STDERR "$progname: executing: $cmd\n" if ($verbose > 1);
+ @all_files = split (/[\r\n]+/, `$cmd`);
+}
+
+
+# If we're using cacheing, read the cache file and return its contents,
+# if any. This also holds an exclusive lock on the cache file, which
+# has the additional benefit that if two copies of this program are
+# running at once, one will wait for the other, instead of both of
+# them spanking the same file system at the same time.
+#
+my $cache_fd = undef;
+my $cache_file_name = undef;
+my $read_cache_p = 0;
+
+sub read_cache($) {
+ my ($dir) = @_;
+
+ return () unless ($cache_p);
+
+ my $dd = "$ENV{HOME}/Library/Caches"; # MacOS location
+ if (-d $dd) {
+ $cache_file_name = "$dd/org.jwz.xscreensaver.getimage.cache";
+ } elsif (-d "$ENV{HOME}/.cache") { # Gnome "FreeDesktop XDG" location
+ $dd = "$ENV{HOME}/.cache/xscreensaver";
+ if (! -d $dd) { mkdir ($dd) || error ("mkdir $dd: $!"); }
+ $cache_file_name = "$dd/xscreensaver-getimage.cache"
+ } elsif (-d "$ENV{HOME}/tmp") { # If ~/.tmp/ exists, use it.
+ $cache_file_name = "$ENV{HOME}/tmp/.xscreensaver-getimage.cache";
+ } else {
+ $cache_file_name = "$ENV{HOME}/.xscreensaver-getimage.cache";
+ }
+
+ print STDERR "$progname: awaiting lock: $cache_file_name\n"
+ if ($verbose > 1);
+
+ my $file = $cache_file_name;
+ open ($cache_fd, '+>>', $file) || error ("unable to write $file: $!");
+ flock ($cache_fd, LOCK_EX) || error ("unable to lock $file: $!");
+ seek ($cache_fd, 0, 0) || error ("unable to rewind $file: $!");
+
+ my $mtime = (stat($cache_fd))[9];
+
+ if ($mtime + $cache_max_age < time) {
+ print STDERR "$progname: cache is too old\n" if ($verbose);
+ return ();
+ }
+
+ my $odir = <$cache_fd>;
+ $odir =~ s/[\r\n]+$//s if defined ($odir);
+ if (!defined ($odir) || ($dir ne $odir)) {
+ print STDERR "$progname: cache is for $odir, not $dir\n"
+ if ($verbose && $odir);
+ return ();
+ }
+
+ my @files = ();
+ while (<$cache_fd>) {
+ s/[\r\n]+$//s;
+ push @files, "$odir/$_";
+ }
+
+ print STDERR "$progname: " . ($#files+1) . " files in cache\n"
+ if ($verbose);
+
+ $read_cache_p = 1;
+ return @files;
+}
+
+
+sub write_cache($) {
+ my ($dir) = @_;
+
+ return unless ($cache_p);
+
+ # If we read the cache, just close it without rewriting it.
+ # If we didn't read it, then write it now.
+
+ if (! $read_cache_p) {
+
+ truncate ($cache_fd, 0) ||
+ error ("unable to truncate $cache_file_name: $!");
+ seek ($cache_fd, 0, 0) ||
+ error ("unable to rewind $cache_file_name: $!");
+
+ if ($#all_files >= 0) {
+ print $cache_fd "$dir\n";
+ foreach (@all_files) {
+ my $f = $_; # stupid Perl. do this to avoid modifying @all_files!
+ $f =~ s@^\Q$dir/@@so || die; # remove $dir from front
+ print $cache_fd "$f\n";
+ }
+ }
+
+ print STDERR "$progname: cached " . ($#all_files+1) . " files\n"
+ if ($verbose);
+ }
+
+ flock ($cache_fd, LOCK_UN) ||
+ error ("unable to unlock $cache_file_name: $!");
+ close ($cache_fd);
+ $cache_fd = undef;
+}
+
+
+sub html_unquote($) {
+ my ($h) = @_;
+
+ # This only needs to handle entities that occur in RSS, not full HTML.
+ my %ent = ( 'amp' => '&', 'lt' => '<', 'gt' => '>',
+ 'quot' => '"', 'apos' => "'" );
+ $h =~ s/(&(\#)?([[:alpha:]\d]+);?)/
+ {
+ my ($o, $c) = ($1, $3);
+ if (! defined($2)) {
+ $c = $ent{$c}; # for <
+ } else {
+ if ($c =~ m@^x([\dA-F]+)$@si) { # for A
+ $c = chr(hex($1));
+ } elsif ($c =~ m@^\d+$@si) { # for A
+ $c = chr($c);
+ } else {
+ $c = undef;
+ }
+ }
+ ($c || $o);
+ }
+ /gexi;
+ return $h;
+}
+
+
+
+sub set_proxy($) {
+ my ($ua) = @_;
+
+ if (!defined($ENV{http_proxy}) && !defined($ENV{HTTP_PROXY})) {
+ my $proxy_data = `scutil --proxy 2>/dev/null`;
+ my ($server) = ($proxy_data =~ m/\bHTTPProxy\s*:\s*([^\s]+)/s);
+ my ($port) = ($proxy_data =~ m/\bHTTPPort\s*:\s*([^\s]+)/s);
+ if ($server) {
+ # Note: this ignores the "ExceptionsList".
+ $ENV{http_proxy} = "http://" . $server . ($port ? ":$port" : "") . "/";
+ print STDERR "$progname: MacOS proxy: $ENV{http_proxy}\n"
+ if ($verbose > 2)
+ }
+ }
+
+ $ua->env_proxy();
+}
+
+
+sub init_lwp() {
+ if (! defined ($LWP::Simple::ua)) {
+ error ("\n\n\tPerl is broken. Do this to repair it:\n" .
+ "\n\tsudo cpan LWP::Simple\n");
+ }
+ set_proxy ($LWP::Simple::ua);
+}
+
+
+# Returns a list of the image enclosures in the RSS or Atom feed.
+# Elements of the list are references, [ "url", "guid" ].
+#
+sub parse_feed($);
+sub parse_feed($) {
+ my ($url) = @_;
+
+ init_lwp();
+ $LWP::Simple::ua->agent ("$progname/$version");
+ $LWP::Simple::ua->timeout (10); # bail sooner than the default of 3 minutes
+
+ my $body = (LWP::Simple::get($url) || '');
+
+ if ($body !~ m@^<\?xml\s@si) {
+ # Not an RSS/Atom feed. Try RSS autodiscovery.
+
+ # (Great news, everybody: Flickr no longer provides RSS for "Sets",
+ # only for "Photostreams", and only the first 20 images of those.
+ # Thanks, assholes.)
+
+ error ("not an RSS or Atom feed, or HTML: $url")
+ unless ($body =~ m@<(HEAD|BODY|A|IMG)\b@si);
+
+ # Find the first <link> with RSS or Atom in it, and use that instead.
+
+ $body =~ s@<LINK\s+([^<>]*)>@{
+ my $p = $1;
+ if ($p =~ m! \b REL \s* = \s* ['"]? alternate \b!six &&
+ $p =~ m! \b TYPE \s* = \s* ['"]? application/(atom|rss) !six &&
+ $p =~ m! \b HREF \s* = \s* ['"] ( [^<>'"]+ ) !six
+ ) {
+ my $u2 = html_unquote ($1);
+ if ($u2 =~ m!^/!s) {
+ my ($h) = ($url =~ m!^([a-z]+://[^/]+)!si);
+ $u2 = "$h$u2";
+ }
+ print STDERR "$progname: found feed: $u2\n"
+ if ($verbose);
+ return parse_feed ($u2);
+ }
+ '';
+ }@gsexi;
+
+ error ("no RSS or Atom feed for HTML page: $url");
+ }
+
+
+ $body =~ s@(<ENTRY|<ITEM)@\001$1@gsi;
+ my @items = split(/\001/, $body);
+ shift @items;
+
+ my @imgs = ();
+ my %ids;
+
+ foreach my $item (@items) {
+ my $iurl = undef;
+ my $id = undef;
+
+ # First look for <link rel="enclosure" href="...">
+ #
+ if (! $iurl) {
+ $item =~ s!(<LINK[^<>]*>)!{
+ my $link = $1;
+ my ($rel) = ($link =~ m/\bREL\s*=\s*[\"\']?([^<>\'\"]+)/si);
+ my ($type) = ($link =~ m/\bTYPE\s*=\s*[\"\']?([^<>\'\"]+)/si);
+ my ($href) = ($link =~ m/\bHREF\s*=\s*[\"\']([^<>\'\"]+)/si);
+
+ if ($rel && lc($rel) eq 'enclosure') {
+ if ($type) {
+ $href = undef unless ($type =~ m@^image/@si); # omit videos
+ }
+ $iurl = html_unquote($href) if $href;
+ }
+ $link;
+ }!gsexi;
+ }
+
+ # Then look for <media:content url="...">
+ #
+ if (! $iurl) {
+ $item =~ s!(<MEDIA:CONTENT[^<>]*>)!{
+ my $link = $1;
+ my ($href) = ($link =~ m/\bURL\s*=\s*[\"\']([^<>\'\"]+)/si);
+ $iurl = html_unquote($href) if $href;
+ $link;
+ }!gsexi;
+ }
+
+ # Then look for <enclosure url="..."/>
+ #
+ if (! $iurl) {
+ $item =~ s!(<ENCLOSURE[^<>]*>)!{
+ my $link = $1;
+ my ($type) = ($link =~ m/\bTYPE\s*=\s*[\"\']?([^<>\'\"]+)/si);
+ my ($href) = ($link =~ m/\bURL\s*=\s*[\"\']([^<>\'\"]+)/si);
+ $iurl = html_unquote($href)
+ if ($href && $type && $type =~ m@^image/@si); # omit videos
+ $link;
+ }!gsexi;
+ }
+
+ # Ok, maybe there's an image in the <url> field?
+ #
+ if (! $iurl) {
+ $item =~ s!((<URL\b[^<>]*>)([^<>]*))!{
+ my ($all, $u2) = ($1, $3);
+ $iurl = html_unquote($u2) if ($u2 =~ m/$good_file_re/io);
+ $all;
+ }!gsexi;
+ }
+
+ # Then look for <description>... with an <img src="..."> inside.
+ #
+ if (! $iurl) {
+ $item =~ s!(<description[^<>]*>.*?</description>)!{
+ my $desc = $1;
+ $desc = html_unquote($desc);
+ my ($href) = ($desc =~ m@<IMG[^<>]*\bSRC=[\"\']?([^\"\'<>]+)@si);
+ $iurl = $href if ($href);
+ $desc;
+ }!gsexi;
+ }
+
+ # Could also do <content:encoded>, but the above probably covers all
+ # of the real-world possibilities.
+
+
+ # Find a unique ID for this image, to defeat image farms.
+ # First look for <id>...</id>
+ ($id) = ($item =~ m!<ID\b[^<>]*>\s*([^<>]+?)\s*</ID>!si) unless $id;
+
+ # Then look for <guid isPermaLink=...> ... </guid>
+ ($id) = ($item =~ m!<GUID\b[^<>]*>\s*([^<>]+?)\s*</GUID>!si) unless $id;
+
+ # Then look for <link> ... </link>
+ ($id) = ($item =~ m!<LINK\b[^<>]*>\s*([^<>]+?)\s*</LINK>!si) unless $id;
+
+
+ if ($iurl) {
+ $id = $iurl unless $id;
+ my $o = $ids{$id};
+ if (! $o) {
+ $ids{$id} = $iurl;
+ my @P = ($iurl, $id);
+ push @imgs, \@P;
+ } elsif ($iurl ne $o) {
+ print STDERR "$progname: WARNING: dup ID \"$id\"" .
+ " for \"$o\" and \"$iurl\"\n";
+ }
+ }
+ }
+
+ return @imgs;
+}
+
+
+# Like md5_base64 but uses filename-safe characters.
+#
+sub md5_file($) {
+ my ($s) = @_;
+ $s = md5_base64($s);
+ $s =~ s@[/]@_@gs;
+ $s =~ s@[+]@-@gs;
+ return $s;
+}
+
+
+# Given the URL of an image, download it into the given directory
+# and return the file name.
+#
+sub download_image($$$) {
+ my ($url, $uid, $dir) = @_;
+
+ my $url2 = $url;
+ $url2 =~ s/\#.*$//s; # Omit search terms after file extension
+ $url2 =~ s/\?.*$//s;
+ my ($ext) = ($url2 =~ m@\.([a-z\d]+)$@si);
+
+ # If the feed hasn't put a sane extension on their URLs, nothing's going
+ # to work. This code assumes that file names have extensions, even the
+ # ones in the cache directory.
+ #
+ if (! $ext) {
+ print STDERR "$progname: skipping extensionless URL: $url\n"
+ if ($verbose > 1);
+ return undef;
+ }
+
+ # Don't bother downloading files that we will reject anyway.
+ #
+ if (! ($url2 =~ m/$good_file_re/io)) {
+ print STDERR "$progname: skipping non-image URL: $url\n"
+ if ($verbose > 1);
+ return undef;
+ }
+
+ my $file = md5_file ($uid);
+ $file .= '.' . lc($ext) if $ext;
+
+ # Don't bother doing If-Modified-Since to see if the URL has changed.
+ # If we have already downloaded it, assume it's good.
+ if (-f "$dir/$file") {
+ print STDERR "$progname: exists: $dir/$file for $uid / $url\n"
+ if ($verbose > 1);
+ return $file;
+ }
+
+ # Special-case kludge for Flickr:
+ # Their RSS feeds sometimes include only the small versions of the images.
+ # So if the URL ends in one of the "small-size" letters, change it to "b".
+ #
+ # _o orig, 1600 +
+ # _k large, 2048 max
+ # _h large, 1600 max
+ # _b large, 1024 max
+ # _c medium, 800 max
+ # _z medium, 640 max
+ # "" medium, 500 max
+ # _n small, 320 max
+ # _m small, 240 max
+ # _t thumb, 100 max
+ # _q square, 150x150
+ # _s square, 75x75
+ #
+ $url =~ s@_[sqtmnzc](\.[a-z]+)$@_b$1@si
+ if ($url =~ m@^https?://[^/?#&]*?flickr\.com/@si);
+
+ print STDERR "$progname: downloading: $dir/$file for $uid / $url\n"
+ if ($verbose > 1);
+ init_lwp();
+ $LWP::Simple::ua->agent ("$progname/$version");
+ my $status = LWP::Simple::mirror ($url, "$dir/$file");
+ if (!LWP::Simple::is_success ($status)) {
+ print STDERR "$progname: error $status: $url\n"; # keep going
+ }
+
+ return $file;
+}
+
+
+sub mirror_feed($) {
+ my ($url) = @_;
+
+ if ($url !~ m/^https?:/si) { # not a URL: local directory.
+ return (undef, $url);
+ }
+
+ my $dir = "$ENV{HOME}/Library/Caches"; # MacOS location
+ if (-d $dir) {
+ $dir = "$dir/org.jwz.xscreensaver.feeds";
+ } elsif (-d "$ENV{HOME}/.cache") { # Gnome "FreeDesktop XDG" location
+ $dir = "$ENV{HOME}/.cache/xscreensaver";
+ if (! -d $dir) { mkdir ($dir) || error ("mkdir $dir: $!"); }
+ $dir .= "/feeds";
+ if (! -d $dir) { mkdir ($dir) || error ("mkdir $dir: $!"); }
+ } elsif (-d "$ENV{HOME}/tmp") { # If ~/.tmp/ exists, use it.
+ $dir = "$ENV{HOME}/tmp/.xscreensaver-feeds";
+ } else {
+ $dir = "$ENV{HOME}/.xscreensaver-feeds";
+ }
+
+ if (! -d $dir) {
+ mkdir ($dir) || error ("mkdir $dir: $!");
+ print STDERR "$progname: mkdir $dir/\n" if ($verbose);
+ }
+
+ # MD5 for directory name to use for cache of a feed URL.
+ $dir .= '/' . md5_file ($url);
- print STDERR "$progname: recursively reading $dir...\n" if ($verbose > 1);
- find_all_files ($dir);
- print STDERR "$progname: found " . ($#all_files+1) . " files\n"
+ if (! -d $dir) {
+ mkdir ($dir) || error ("mkdir $dir: $!");
+ print STDERR "$progname: mkdir $dir/ for $url\n" if ($verbose);
+ }
+
+ # At this point, we have the directory corresponding to this URL.
+ # Now check to see if the files in it are up to date, and download
+ # them if not.
+
+ my $stamp = '.timestamp';
+ my $lock = "$dir/$stamp";
+
+ print STDERR "$progname: awaiting lock: $lock\n"
if ($verbose > 1);
- @all_files = sort(@all_files);
+ my $mtime = ((stat($lock))[9]) || 0;
+
+ my $lock_fd;
+ open ($lock_fd, '+>>', $lock) || error ("unable to write $lock: $!");
+ flock ($lock_fd, LOCK_EX) || error ("unable to lock $lock: $!");
+ seek ($lock_fd, 0, 0) || error ("unable to rewind $lock: $!");
+
+ my $poll_p = ($mtime + $feed_max_age < time);
+
+ # --no-cache cmd line arg means poll again right now.
+ $poll_p = 1 unless ($cache_p);
+
+ # Even if the cache is young, make sure there is at least one file,
+ # and re-check if not.
+ #
+ if (! $poll_p) {
+ my $count = 0;
+ opendir (my $dirh, $dir) || error ("$dir: $!");
+ foreach my $f (readdir ($dirh)) {
+ next if ($f =~ m/^\./s);
+ $count++;
+ last;
+ }
+ closedir $dirh;
+
+ if ($count <= 0) {
+ print STDERR "$progname: no files in cache of $url\n" if ($verbose);
+ $poll_p = 1;
+ }
+ }
+
+ if ($poll_p) {
+
+ print STDERR "$progname: loading $url\n" if ($verbose);
+
+ my %files;
+ opendir (my $dirh, $dir) || error ("$dir: $!");
+ foreach my $f (readdir ($dirh)) {
+ next if ($f eq '.' || $f eq '..');
+ $files{$f} = 0; # 0 means "file exists, should be deleted"
+ }
+ closedir $dirh;
+
+ $files{$stamp} = 1;
+
+ # Download each image currently in the feed.
+ #
+ my $count = 0;
+ my @urls = parse_feed ($url);
+ print STDERR "$progname: " . ($#urls + 1) . " images\n"
+ if ($verbose > 1);
+ foreach my $p (@urls) {
+ my ($furl, $id) = @$p;
+ my $f = download_image ($furl, $id, $dir);
+ next unless $f;
+ $files{$f} = 1; # Got it, don't delete
+ $count++;
+ }
+
+ my $empty_p = ($count <= 0);
+
+ # Now delete any files that are no longer in the feed.
+ # But if there was nothing in the feed (network failure?)
+ # then don't blow away the old files.
+ #
+ my $kept = 0;
+ foreach my $f (keys(%files)) {
+ if ($count <= 0) {
+ $kept++;
+ } elsif ($files{$f}) {
+ $kept++;
+ } else {
+ if (unlink ("$dir/$f")) {
+ print STDERR "$progname: rm $dir/$f\n" if ($verbose > 1);
+ } else {
+ print STDERR "$progname: rm $dir/$f: $!\n"; # don't bail
+ }
+ }
+ }
+
+ # Both feed and cache are empty. No files at all. Bail.
+ error ("empty feed: $url") if ($kept <= 1);
+
+ # Feed is empty, but we have some files from last time. Warn.
+ print STDERR "$progname: empty feed: using cache: $url\n"
+ if ($empty_p);
+
+ $mtime = time(); # update the timestamp
+
+ } else {
+
+ # Not yet time to re-check the URL.
+ print STDERR "$progname: using cache: $url\n" if ($verbose);
+
+ }
+
+ # Unlock and update the write date on the .timestamp file.
+ #
+ truncate ($lock_fd, 0) || error ("unable to truncate $lock: $!");
+ seek ($lock_fd, 0, 0) || error ("unable to rewind $lock: $!");
+ utime ($mtime, $mtime, $lock_fd) || error ("unable to touch $lock: $!");
+ flock ($lock_fd, LOCK_UN) || error ("unable to unlock $lock: $!");
+ close ($lock_fd);
+ $lock_fd = undef;
+ print STDERR "$progname: unlocked $lock\n" if ($verbose > 1);
+
+ # Don't bother using the imageDirectory cache. We know that this directory
+ # is flat, and we can assume that an RSS feed doesn't contain 100,000 images
+ # like ~/Pictures/ might.
+ #
+ $cache_p = 0;
+
+ # Return the URL and directory name of the files of that URL's local cache.
+ #
+ return ($url, $dir);
+}
+
+
+sub find_random_file($) {
+ my ($dir) = @_;
+
+ if ($use_spotlight_p == -1) {
+ $use_spotlight_p = 0;
+ if (-x '/usr/bin/mdfind') {
+ $use_spotlight_p = 1;
+ }
+ }
+
+ my $url;
+ ($url, $dir) = mirror_feed ($dir);
+
+ if ($url) {
+ $use_spotlight_p = 0;
+ print STDERR "$progname: $dir is cache for $url\n" if ($verbose > 1);
+ }
+
+ @all_files = read_cache ($dir);
+
+ if ($#all_files >= 0) {
+ # got it from the cache...
+
+ } elsif ($use_spotlight_p) {
+ print STDERR "$progname: spotlighting $dir...\n" if ($verbose);
+ spotlight_all_files ($dir);
+ print STDERR "$progname: found " . ($#all_files+1) .
+ " file" . ($#all_files == 0 ? "" : "s") .
+ " via Spotlight\n"
+ if ($verbose);
+ } else {
+ print STDERR "$progname: recursively reading $dir...\n" if ($verbose);
+ find_all_files ($dir);
+ print STDERR "$progname: " .
+ "f=" . ($#all_files+1) . "; " .
+ "d=$dir_count; " .
+ "s=$stat_count; " .
+ "skip=${skip_count_unstat}+$skip_count_stat=" .
+ ($skip_count_unstat + $skip_count_stat) .
+ ".\n"
+ if ($verbose);
+ }
+
+ write_cache ($dir);
if ($#all_files < 0) {
print STDERR "$progname: no files in $dir\n";
exit 1;
}
- my $n = int (rand ($#all_files + 1));
- my $file = $all_files[$n];
+ my $max_tries = 50;
+ for (my $i = 0; $i < $max_tries; $i++) {
- print STDERR "$progname: chose file $n: $file\n" if ($verbose > 1);
- return $file;
+ my $n = int (rand ($#all_files + 1));
+ my $file = $all_files[$n];
+ if (large_enough_p ($file)) {
+ if (! $url) {
+ $file =~ s@^\Q$dir/@@so || die; # remove $dir from front
+ }
+ return $file;
+ }
+ }
+
+ print STDERR "$progname: no suitable images in $dir " .
+ "(after $max_tries tries)\n";
+
+ # If we got here, blow away the cache. Maybe it's stale.
+ unlink $cache_file_name if $cache_file_name;
+
+ exit 1;
}
+sub large_enough_p($) {
+ my ($file) = @_;
+
+ my ($w, $h) = image_file_size ($file);
+
+ if (!defined ($h)) {
-sub display_file {
- my ($file, $displayer) = @_;
+ # Nonexistent files are obviously too small!
+ # Already printed $verbose message about the file not existing.
+ return 0 unless -f $file;
- if (!defined($displayer)) {
- print STDOUT "$file\n";
- } else {
- my @cmd = split (/ +/, $displayer);
- push @cmd, $file; # do it this way to allow file names with spaces.
- print STDERR "$progname: executing \"" . join(" ", @cmd) . "\"\n"
+ print STDERR "$progname: $file: unable to determine image size\n"
if ($verbose);
- exec (@cmd) || die;
+ # Assume that unknown files are of good sizes: this will happen if
+ # they matched $good_file_re, but we don't have code to parse them.
+ # (This will also happen if the file is junk...)
+ return 1;
}
+
+ if ($w < $min_image_width || $h < $min_image_height) {
+ print STDERR "$progname: $file: too small ($w x $h)\n" if ($verbose);
+ return 0;
+ }
+
+ print STDERR "$progname: $file: $w x $h\n" if ($verbose);
+ return 1;
}
-sub find_and_display {
- my ($dir, $displayer) = @_;
- my $file = find_random_file ($dir);
- display_file ($file, $displayer);
+
+# Given the raw body of a GIF document, returns the dimensions of the image.
+#
+sub gif_size($) {
+ my ($body) = @_;
+ my $type = substr($body, 0, 6);
+ my $s;
+ return () unless ($type =~ /GIF8[7,9]a/);
+ $s = substr ($body, 6, 10);
+ my ($a,$b,$c,$d) = unpack ("C"x4, $s);
+ return (($b<<8|$a), ($d<<8|$c));
+}
+
+# Given the raw body of a JPEG document, returns the dimensions of the image.
+#
+sub jpeg_size($) {
+ my ($body) = @_;
+ my $i = 0;
+ my $L = length($body);
+
+ my $c1 = substr($body, $i, 1); $i++;
+ my $c2 = substr($body, $i, 1); $i++;
+ return () unless (ord($c1) == 0xFF && ord($c2) == 0xD8);
+
+ my $ch = "0";
+ while (ord($ch) != 0xDA && $i < $L) {
+ # Find next marker, beginning with 0xFF.
+ while (ord($ch) != 0xFF) {
+ return () if (length($body) <= $i);
+ $ch = substr($body, $i, 1); $i++;
+ }
+ # markers can be padded with any number of 0xFF.
+ while (ord($ch) == 0xFF) {
+ return () if (length($body) <= $i);
+ $ch = substr($body, $i, 1); $i++;
+ }
+
+ # $ch contains the value of the marker.
+ my $marker = ord($ch);
+
+ if (($marker >= 0xC0) &&
+ ($marker <= 0xCF) &&
+ ($marker != 0xC4) &&
+ ($marker != 0xCC)) { # it's a SOFn marker
+ $i += 3;
+ return () if (length($body) <= $i);
+ my $s = substr($body, $i, 4); $i += 4;
+ my ($a,$b,$c,$d) = unpack("C"x4, $s);
+ return (($c<<8|$d), ($a<<8|$b));
+
+ } else {
+ # We must skip variables, since FFs in variable names aren't
+ # valid JPEG markers.
+ return () if (length($body) <= $i);
+ my $s = substr($body, $i, 2); $i += 2;
+ my ($c1, $c2) = unpack ("C"x2, $s);
+ my $length = ($c1 << 8) | $c2;
+ return () if ($length < 2);
+ $i += $length-2;
+ }
+ }
+ return ();
+}
+
+# Given the raw body of a PNG document, returns the dimensions of the image.
+#
+sub png_size($) {
+ my ($body) = @_;
+ return () unless ($body =~ m/^\211PNG\r/s);
+ my ($bits) = ($body =~ m/^.{12}(.{12})/s);
+ return () unless defined ($bits);
+ return () unless ($bits =~ /^IHDR/);
+ my ($ign, $w, $h) = unpack("a4N2", $bits);
+ return ($w, $h);
}
-sub usage {
- print STDERR "usage: $progname [--verbose] [--name] directory\n";
- print STDERR "Puts a randomly selected image on the root window.\n";
- print STDERR "With --name, merely prints the filename to stdout.\n";
+# Given the raw body of a GIF, JPEG, or PNG document, returns the dimensions
+# of the image.
+#
+sub image_size($) {
+ my ($body) = @_;
+ return () if (length($body) < 10);
+ my ($w, $h) = gif_size ($body);
+ if ($w && $h) { return ($w, $h); }
+ ($w, $h) = jpeg_size ($body);
+ if ($w && $h) { return ($w, $h); }
+ # #### TODO: need image parsers for TIFF, XPM, XBM.
+ return png_size ($body);
+}
+
+# Returns the dimensions of the image file.
+#
+sub image_file_size($) {
+ my ($file) = @_;
+ my $in;
+ if (! open ($in, '<:raw', $file)) {
+ print STDERR "$progname: $file: $!\n" if ($verbose);
+ return ();
+ }
+ my $body = '';
+ sysread ($in, $body, 1024 * 50); # The first 50k should be enough.
+ close $in; # (It's not for certain huge jpegs...
+ return image_size ($body); # but we know they're huge!)
+}
+
+
+sub error($) {
+ my ($err) = @_;
+ print STDERR "$progname: $err\n";
exit 1;
}
-sub main {
+sub usage() {
+ print STDERR "usage: $progname [--verbose] directory-or-feed-url\n\n" .
+ " Prints the name of a randomly-selected image file. The directory\n" .
+ " is searched recursively. Images smaller than " .
+ "${min_image_width}x${min_image_height} are excluded.\n" .
+ "\n" .
+ " The directory may also be the URL of an RSS/Atom feed. Enclosed\n" .
+ " images will be downloaded and cached locally.\n" .
+ "\n";
+ exit 1;
+}
+
+sub main() {
my $dir = undef;
- my $do_name = 0;
while ($_ = $ARGV[0]) {
shift @ARGV;
- if ($_ eq "--verbose") { $verbose++; }
- elsif (m/^-v+$/) { $verbose += length($_)-1; }
- elsif ($_ eq "--name") { $do_name++; }
- elsif (m/^-./) { usage; }
- elsif (!defined($dir)) { $dir = $_; }
- else { usage; }
+ if (m/^--?verbose$/s) { $verbose++; }
+ elsif (m/^-v+$/s) { $verbose += length($_)-1; }
+ elsif (m/^--?name$/s) { } # ignored, for compatibility
+ elsif (m/^--?spotlight$/s) { $use_spotlight_p = 1; }
+ elsif (m/^--?no-spotlight$/s) { $use_spotlight_p = 0; }
+ elsif (m/^--?cache$/s) { $cache_p = 1; }
+ elsif (m/^--?no-?cache$/s) { $cache_p = 0; }
+ elsif (m/^-./) { usage; }
+ elsif (!defined($dir)) { $dir = $_; }
+ else { usage; }
}
usage unless (defined($dir));
- my $displayer = undef;
- $displayer = pick_displayer() unless $do_name;
+ $dir =~ s@^feed:@http:@si;
- if (-d $dir) {
- find_and_display ($dir, $displayer);
- } elsif (-f $dir) {
- display_file ($dir, $displayer);
+ if ($dir =~ m/^https?:/si) {
+ # ok
} else {
- usage();
+ $dir =~ s@^~/@$ENV{HOME}/@s; # allow literal "~/"
+ $dir =~ s@/+$@@s; # omit trailing /
+
+ if (! -d $dir) {
+ print STDERR "$progname: $dir: not a directory or URL\n";
+ usage;
+ }
}
+
+ my $file = find_random_file ($dir);
+ print STDOUT "$file\n";
}
main;
projects / xscreensaver / blobdiff