Bump version to v1.0.1

Signed-off-by: Nicolás Ortega Froysa <nicolas@ortegas.org>

.gitignore

@@ -0,0 +1,2 @@
+pacundo
+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: pacundo.pl
+	pp -o $@ $^
+
+pacundo.1.gz: pacundo.1
+	gzip -c $^ > $@
+
+.PHONY: install clean
+
+clean:
+	$(RM) pacundo
+	$(RM) pacundo.1.gz
+
+install: pacundo pacundo.1.gz
+	install -d $(PREFIX)/bin
+	install -m 755 pacundo $(PREFIX)/bin/
+	install -d $(PREFIX)/share/man/man1
+	install -m 644 pacundo.1.gz $(PREFIX)/share/man/man1/

README.md

@@ -7,10 +7,47 @@ to boot from a USB depending on just how broken it is).
 
 ## Installation
 
-Dependencies:
+### Dependencies
 
 - Perl 5
 - `File::ReadBackwards` module
+- PAR Packager (for compiling)
+- GNU Makefile
+
+You can install these packages with the following command:
+
+```console
+# pacman -S perl perl-file-readbackwards perl-par-packer
+```
+
+### 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)
 
 ## License
 

pacundo.1

@@ -0,0 +1,49 @@
+.TH PACUNDO "1" "April 2024" "pacundo 1.0.1" "User Commands"
+.SH "NAME"
+pacundo - A time machine to return your ArchLinux machine back 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

@@ -29,8 +29,8 @@ use feature qw(signatures);
 use Getopt::Std;
 use File::ReadBackwards;
 
-my $VERSION   = "1.0";
+my $VERSION   = '1.0.1';
-my $PROG_NAME = "pacundo";
+my $PROG_NAME = 'pacundo';
 
 sub print_version() {
 	print("$PROG_NAME v$VERSION\n");
@@ -47,9 +47,9 @@ USAGE:
 	$PROG_NAME -v
 
 OPTIONS:
-	-i         Enter interactive mode to select packages to downgrade [default behavior]
+	-i         Enter interactive mode to select package operations to undo (default behavior)
-	-r         Automatically downgrade all packages from last upgrade
+	-r         Non-interactively undo entire transactions
-	-t <num>   Specify the number of transactions to include for undoing selection [default 1]
+	-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");
@@ -60,8 +60,8 @@ sub read_txs($num_txs = 1) {
 	my $found_txs = 0;
 	my $in_tx = 0;
 	my @undo_txs;
-	my $pacman_log = File::ReadBackwards->new("/var/log/pacman.log") or
+	my $pacman_log = File::ReadBackwards->new('/var/log/pacman.log') or
-		die("Failed to load pacman log file.\n$!");
+		die("Failed to load pacman log file.\n$!\n");
 
 	while ($found_txs < $num_txs && defined(my $line = $pacman_log->readline)) {
 		unless ($in_tx) {
@@ -77,18 +77,18 @@ sub read_txs($num_txs = 1) {
 				$line =~ /\[ALPM\] (upgraded|downgraded) ([^\s]+) \((.*) -> (.*)\)/;
 			push(@undo_txs,
 				{
-					'action' => $action,
+					action   => $action,
-					'pkg_name' => $pkg_name,
+					pkg_name => $pkg_name,
-					'oldver' => $oldver,
+					oldver   => $oldver,
-					'newver' => $newver,
+					newver   => $newver,
 				}
 			);
 		} elsif ($line =~ /\[ALPM\] (installed|removed)/) {
 			my ($action, $pkg_name) = $line =~ /\[ALPM\] (installed|removed) ([^\s]+)/;
 			push(@undo_txs,
 				{
-					'action' => $action,
+					action   => $action,
-					'pkg_name' => $pkg_name,
+					pkg_name => $pkg_name,
 				}
 			);
 		}
@@ -118,8 +118,7 @@ $n, $tx->{action}, $tx->{pkg_name}
 		$n++;
 	}
 
-	print("Select transactions to undo (e.g. '1 2 3', '1-3')\n");
+	print("Select transactions to undo (e.g. '1 2 3', '1-3')\n> ");
-	print("> ");
 
 	my @sel = split(' ', <STDIN>);
 
@@ -129,7 +128,7 @@ $n, $tx->{action}, $tx->{pkg_name}
 		push(@sel, ($start..$end));
 	}
 
-	@sel = sort grep({!/[0-9+]-[0-9+]/} @sel);
+	@sel = sort grep({!/[0-9]+-[0-9]+/} @sel);
 
 	my @sel_undo;
 	push(@sel_undo, $undo_txs[$_-1]) foreach (@sel);
@@ -137,30 +136,79 @@ $n, $tx->{action}, $tx->{pkg_name}
 	return @sel_undo;
 }
 
+# NOTE: Currently this subroutine only works for pacman and yay. You'll have to
+# add options for additional AUR helpers.
 sub get_pkgmgr() {
-	my $mgr = $ENV{DEFAULT_PKGMGR} // 'pacman';
+	my $mgr = '';
-	my $mgr_bin = `which $mgr`;
+	my $mgr_bin;
+	my @supported_mgrs = (
+		'yay',
+		'pacman',
+	);
+	my $sudo = '';
+	my $user = $ENV{LOGNAME} || $ENV{USER};
 
-	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;
 	}
+	chomp($mgr_bin);
 
-	my $mgr_cmd_search = "$mgr_bin -Ss";
+	if ($mgr eq 'pacman' && $user ne 'root') {
-	my $mgr_cmd_install_remote = "$mgr_bin -S";
+		$sudo = 'sudo';
-	my $mgr_cmd_install_local = "$mgr_bin -U";
+	}
 
 	my %pkgmgr = (
 		name           => $mgr,
 		bin            => $mgr_bin,
-		search         => $mgr_cmd_search,
+		search         => "$mgr_bin -Ss",
-		install_remote => $mgr_cmd_install_remote,
+		info           => "$mgr_bin -Si",
-		install_local  => $mgr_cmd_install_local,
+		install_remote => "$sudo $mgr_bin -S",
+		install_local  => "$sudo $mgr_bin -U",
+		remove         => "$sudo $mgr_bin -R",
 	);
 
 	return \%pkgmgr;
 }
 
+sub find_local_pkg($pkgmgr, $pkg_name, $pkg_ver='') {
+	my $pkg_file = '';
+	my $pkg_pat;
+	my $repo = `$pkgmgr->{info} $pkg_name | awk '{ if (\$1 == "Repository") print \$3; }'`;;
+
+	if ($pkg_ver ne '') {
+		$pkg_pat = "$pkg_name-$pkg_ver-*.pkg.tar.zst";
+	} else {
+		$pkg_pat = "$pkg_name-*.pkg.tar.zst";
+	}
+
+	if ($repo eq 'aur') {
+		my $aur_dir;
+
+		if ($pkgmgr->{name} eq 'yay') {
+			$aur_dir = "$ENV{'XDG_CACHE_HOME'}/yay/$pkg_name";
+		} else {
+			return '';
+		}
+
+		$pkg_file = `ls $aur_dir/$pkg_pat | tail -n1`;
+	} else {
+		$pkg_file = `ls /var/cache/pacman/pkg/$pkg_pat | tail -n1`;
+	}
+
+	chomp($pkg_file);
+
+	return $pkg_file;
+}
+
 getopts("irt:dvh", \my %opts);
 
 if ($opts{'v'}) {
@@ -187,3 +235,37 @@ my @undo_txs = &read_txs($num_txs);
 
 # Interactive mode
 @undo_txs = &select_txs(@undo_txs) unless ($r_flag);
+
+my $remove_pkgs = "";          # executed via -R
+my $remote_install_pkgs = "";  # executed via -S
+my $local_install_pkgs = "";   # executed via -U
+
+foreach my $tx (@undo_txs) {
+	if ($tx->{action} eq 'installed') {
+		$remove_pkgs .= "$tx->{pkg_name} ";
+	} elsif ($tx->{action} eq 'removed') {
+		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}, $tx->{oldver});
+		if ($pkg_file eq '') {
+			$remote_install_pkgs .= "$tx->{pkg_name} ";
+		} else {
+			$local_install_pkgs .= "$pkg_file ";
+		}
+	}
+}
+
+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 '');
+}