Makefile: simplify install command.

No longer exists.

.gitignore

@@ -0,0 +1 @@
+pacundo.1.gz

Makefile

@@ -0,0 +1,43 @@
+# Copyright (C) 2024 Ortega Froysa, Nicolás <nicolas@ortegas.org> All rights reserved.
+# Author: Ortega Froysa, Nicolás <nicolas@ortegas.org>
+#
+# This software is provided 'as-is', without any express or implied
+# warranty. In no event will the authors be held liable for any damages
+# arising from the use of this software.
+#
+# Permission is granted to anyone to use this software for any purpose,
+# including commercial applications, and to alter it and redistribute it
+# freely, subject to the following restrictions:
+#
+# 1. The origin of this software must not be misrepresented; you must not
+#    claim that you wrote the original software. If you use this software
+#    in a product, an acknowledgment in the product documentation would be
+#    appreciated but is not required.
+#
+# 2. Altered source versions must be plainly marked as such, and must not be
+#    misrepresented as being the original software.
+#
+# 3. This notice may not be removed or altered from any source
+#    distribution.
+
+ifeq ($(PREFIX),)
+	PREFIX := /usr/local
+endif
+
+pacundo.1.gz: pacundo.1
+	gzip -c $^ > $@
+
+.PHONY: clean doc install uninstall
+
+clean:
+	$(RM) pacundo.1.gz
+
+doc: pacundo.1.gz
+
+install: pacundo.1.gz
+	install -Dm755 pacundo.pl $(PREFIX)/bin/pacundo
+	install -Dm644 pacundo.1.gz $(PREFIX)/share/man/man1/
+
+uninstall:
+	$(RM) $(PREFIX)/bin/pacundo
+	$(RM) $(PREFIX)/share/man/man1/pacundo.1.gz

README.md

@@ -7,10 +7,67 @@ to boot from a USB depending on just how broken it is).
 
 ## Installation
 
-Dependencies:
+### Dependencies
 
 - Perl 5
 - `File::ReadBackwards` module
+- cURL
+- GNU Make
+
+You can install these packages with the following command:
+
+```console
+# pacman -S perl perl-file-readbackwards curl
+```
+
+### Compiling & Installing
+
+The script is compiled and installed using GNU Makefile. Therefore you can use
+`make install` to build and install the script and its man-page as expected.
+They are installed (by default) to `/usr/local`. To change this to a different
+directory simply prepend the `PREFIX=<path>` to your `make install` command.
+
+## Usage
+
+The first concept to understand is that of a transaction. A transaction is
+defined in the pacman logs as package operations done during a single use of the
+command (or so it seems, at least). If you look at the logs
+(`/var/log/pacman.log`) this would be everything between the lines `[ALPM]
+transaction started` and `[ALPM] transaction completed`. You can set how many
+transactions to list/undo by using the `-t` argument.
+
+There are two modes for undoing pacman transactions:
+
+- Interactive (`-i`, default): will show you a numbered list with all the package
+  operations of the selected transactions.
+- Automatic (`-r`): will automatically undo all package operations of the
+  selected transactions.
+
+Look at the man-page (`man pacundo`) for more information.
+
+### Supported AUR Helpers
+
+- [yay](https://github.com/Jguer/yay)
+
+## Contributing
+
+If you find any issues, feel free to report them on GitHub or send me an E-Mail
+(see my website/profile for the address). I will add these issues to my personal
+Gitea page and (unless specified otherwise) mention you as the person who found
+the issue.
+
+For patches/pull requests, if you open a PR on GitHub I will likely not merge
+directly but instead apply the patches locally (via Git patches, conserving
+authorship), push them to my Gitea repository, which will finally be mirrored to
+GitHub. However, you can save me a bit of work by just sending me the Git
+patches directly (via E-Mail).
+
+If you're looking for a way to contribute, there are a few to-do items within
+the code which you can find using `grep`:
+
+```console
+# grep -n "TODO" pacundo.pl
+```
 
 ## License
 

pacundo.1

@@ -0,0 +1,49 @@
+.TH PACUNDO "1" "April 2024" "pacundo 1.1.1" "User Commands"
+.SH "NAME"
+pacundo - A time machine to roll back your ArchLinux machine to a working state.
+.SH "SYNOPSIS"
+.B pacundo
+[\fI\-i\fR|\fI\-r\fR] [\fI\-t\fR <\fInum\fR>] [\fI\-d\fR]
+
+.B pacundo
+\fI\-h\fR
+
+.B pacundo
+\fI\-v\fR
+
+.SH "DESCRIPTION"
+This program helps to undo the last pacman/yay transactions automatically, which
+is especially helpful if the last update broke your system for some reason.
+
+\fBNote:\fR the term \fItransaction\fR refers to an operation done by pacman
+(e.g. all packages upgraded by \fIpacman -Syu\fR).
+
+.SH "OPTIONS"
+.TP
+\fB\-i\fR
+Enter interactive mode to select package operations to undo (default behavior)
+.TP
+\fB\-r\fR
+Non-interactively undo entire transactions
+.TP
+\fB\-t\fR <\fInum\fR>
+Specify the number of transactions to include (default: 1)
+.TP
+\fB\-d\fR
+Dry run, i.e. don't actually do anything
+.TP
+\fB\-h\fR
+Show this help information
+.TP
+\fB\-v\fR
+Print program version
+
+.SH "AUTHOR"
+Written by Nicolás A. Ortega Froysa.
+
+.SH "COPYRIGHT"
+Copyright \(co 2024 Ortega Froysa, Nicolás A. <nicolas@ortegas.org>.
+License: ZLib License.
+
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.

pacundo.pl

@@ -29,7 +29,7 @@ use feature qw(signatures);
 use Getopt::Std;
 use File::ReadBackwards;
 
-my $VERSION   = '1.0';
+my $VERSION   = '1.1.1';
 my $PROG_NAME = 'pacundo';
 
 sub print_version() {
@@ -39,7 +39,7 @@ sub print_version() {
 
 sub print_help() {
 	&print_version();
-	print("A time machine to return your ArchLinux machine back to a working state.
+	print("A time machine to roll back your ArchLinux machine to a working state.
 
 USAGE:
 	$PROG_NAME [-i|-r] [-t <num>] [-d]
@@ -47,9 +47,9 @@ USAGE:
 	$PROG_NAME -v
 
 OPTIONS:
-	-i         Enter interactive mode to select packages to downgrade [default behavior]
-	-r         Automatically downgrade all packages from last upgrade
-	-t <num>   Specify the number of transactions to include for undoing selection [default 1]
+	-i         Enter interactive mode to select package operations to undo (default behavior)
+	-r         Non-interactively undo entire transactions
+	-t <num>   Specify the number of transactions to include (default: 1)
 	-d         Dry run, i.e. don't actually do anything
 	-h         Show this help information
 	-v         Print program version\n");
@@ -139,13 +139,24 @@ $n, $tx->{action}, $tx->{pkg_name}
 # NOTE: Currently this subroutine only works for pacman and yay. You'll have to
 # add options for additional AUR helpers.
 sub get_pkgmgr() {
-	# TODO: autodetect AUR helper
-	my $mgr = $ENV{DEFAULT_PKGMGR} // 'pacman';
+	my $mgr = '';
+	my $mgr_bin;
+	my @supported_mgrs = (
+		'yay',
+		'pacman',
+	);
 	my $sudo = '';
 	my $user = $ENV{LOGNAME} || $ENV{USER};
 
-	my $mgr_bin = `which $mgr 2>&1`;
-	if ($? != 0) {
+	foreach my $i (@supported_mgrs) {
+		$mgr_bin = `which $i 2>&1`;
+		if ($? == 0) {
+			$mgr = $i;
+			last;
+		}
+	}
+
+	if ($mgr eq '') {
 		print(STDERR "Failed to find pacman executable. Are you using an ArchLinux system?\n");
 		exit 1;
 	}
@@ -158,7 +169,8 @@ sub get_pkgmgr() {
 	my %pkgmgr = (
 		name           => $mgr,
 		bin            => $mgr_bin,
-		search         => "$sudo $mgr_bin -Ss",
+		search         => "$mgr_bin -Ss",
+		info           => "$mgr_bin -Si",
 		install_remote => "$sudo $mgr_bin -S",
 		install_local  => "$sudo $mgr_bin -U",
 		remove         => "$sudo $mgr_bin -R",
@@ -167,17 +179,76 @@ sub get_pkgmgr() {
 	return \%pkgmgr;
 }
 
-sub find_local_pkg($pkgmgr, $pkg_name, $pkg_ver) {
+sub find_local_pkg($pkgmgr, $pkg_name, $pkg_ver='') {
 	my $pkg_file = '';
-	my $aur_dir = "$ENV{'XDG_CACHE_HOME'}/yay/$pkg_name";
+	my $pkg_pat;
+	my $repo = `$pkgmgr->{info} $pkg_name | awk '{ if (\$1 == "Repository") print \$3; }'`;;
+	chomp($repo);
 
-	if ($pkgmgr->{name} eq 'yay' && -d $aur_dir) {
-		$pkg_file = `ls $aur_dir/$pkg_name-$pkg_ver-*.pkg.tar.zst | tail -n1`;
+	if ($pkg_ver ne '') {
+		$pkg_pat = "$pkg_name-$pkg_ver-*.pkg.tar.zst";
 	} else {
-		$pkg_file = `ls /var/cache/pacman/pkg/$pkg_name-$pkg_ver-*.pkg.tar.zst | tail -n1`;
+		$pkg_pat = "$pkg_name-*.pkg.tar.zst";
+	}
+
+	if ($repo eq 'aur') {
+		my $aur_dir;
+
+		if ($pkgmgr->{name} eq 'yay') {
+			if ($ENV{'XDG_CACHE_HOME'} ne '') {
+				$aur_dir = "$ENV{'XDG_CACHE_HOME'}/yay/$pkg_name";
+			} else {
+				$aur_dir = "$ENV{'HOME'}/.cache/yay/$pkg_name";
+			}
+		} else {
+			return '';
+		}
+
+		$pkg_file = `ls $aur_dir/$pkg_pat 2> /dev/null | tail -n1`;
+	} else {
+		$pkg_file = `ls /var/cache/pacman/pkg/$pkg_pat 2> /dev/null | tail -n1`;
 	}
 
 	chomp($pkg_file);
+
+	return $pkg_file;
+}
+
+sub find_remote_archive($pkgmgr, $pkg_name, $pkg_ver) {
+	my $repo = `$pkgmgr->{info} $pkg_name | awk '{ if (\$1 == "Repository") print \$3; }'`;;
+	chomp($repo);
+	# TODO: look through git history for version.
+	if ($repo eq 'aur') {
+		return '';
+	}
+
+	# TODO: Probably a better way of managing architectures. There should be a
+	# way of getting the architecture of the package.
+	my @archs = (`uname -m`, 'any');
+	my $ala_url = "https://archive.archlinux.org/packages/" .
+		substr($pkg_name,0,1) . "/" . $pkg_name;
+	my $pkg_file = '';
+
+	foreach my $arch (@archs) {
+		chomp($arch);
+		my $filename = "$pkg_name-$pkg_ver-$arch.pkg.tar.zst";
+		my $pkg_url = "$ala_url/$filename";
+		my $output_file = "/tmp/$filename";
+
+		my $resp = `curl -Lo $output_file -s -w '%{http_code}\n' $pkg_url`;
+		chomp($resp);
+		if ($resp eq '200') {
+			system("curl -Lo $output_file.sig -s $pkg_url.sig");
+			$pkg_file = $output_file;
+			last;
+		} else {
+			unlink $output_file;
+		}
+	}
+
+	if ($pkg_file ne '') {
+		print("Downloaded from archive: $pkg_file\n");
+	}
 	return $pkg_file;
 }
 
@@ -216,18 +287,30 @@ foreach my $tx (@undo_txs) {
 	if ($tx->{action} eq 'installed') {
 		$remove_pkgs .= "$tx->{pkg_name} ";
 	} elsif ($tx->{action} eq 'removed') {
-		# TODO: install local package if available
-		$remote_install_pkgs .= "$tx->{pkg_name} ";
-	} else {
-		my $pkg_file = &find_local_pkg($pkgmgr, $tx->{pkg_name}, $tx->{oldver});
+		my $pkg_file = &find_local_pkg($pkgmgr, $tx->{pkg_name});
 		if ($pkg_file eq '') {
 			$remote_install_pkgs .= "$tx->{pkg_name} ";
 		} else {
 			$local_install_pkgs .= "$pkg_file ";
 		}
+	} else {
+		my $pkg_file = &find_local_pkg($pkgmgr, $tx->{pkg_name}, $tx->{oldver});
+		$pkg_file = &find_remote_archive($pkgmgr, $tx->{pkg_name}, $tx->{oldver}) if ($pkg_file eq '');
+
+		if ($pkg_file ne '') {
+			$local_install_pkgs .= "$pkg_file ";
+		} else {
+			print(STDERR "Unable to find $tx->{pkg_name} $tx->{pkg_ver}");
+		}
 	}
 }
 
-system("$pkgmgr->{remove} $remove_pkgs") if ($remove_pkgs ne '');
-system("$pkgmgr->{install_remote} $remote_install_pkgs") if ($remote_install_pkgs ne '');
-system("$pkgmgr->{install_local} $local_install_pkgs") if ($local_install_pkgs ne '');
+if ($dry_run) {
+	print("$pkgmgr->{remove} $remove_pkgs\n") if ($remove_pkgs ne '');
+	print("$pkgmgr->{install_remote} $remote_install_pkgs\n") if ($remote_install_pkgs ne '');
+	print("$pkgmgr->{install_local} $local_install_pkgs\n") if ($local_install_pkgs ne '');
+} else {
+	system("$pkgmgr->{remove} $remove_pkgs") if ($remove_pkgs ne '');
+	system("$pkgmgr->{install_remote} $remote_install_pkgs") if ($remote_install_pkgs ne '');
+	system("$pkgmgr->{install_local} $local_install_pkgs") if ($local_install_pkgs ne '');
+}