1 # Copyright (C) 2002-2024 Free Software Foundation, Inc.
3 # This program is free software; you can redistribute it and/or modify
4 # it under the terms of the GNU General Public License as published by
5 # the Free Software Foundation; either version 2, or (at your option)
8 # This program is distributed in the hope that it will be useful,
9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 # GNU General Public License for more details.
13 # You should have received a copy of the GNU General Public License
14 # along with this program. If not, see <https://www.gnu.org/licenses/>.
16 package Automake
::Location
;
20 use warnings FATAL
=> 'all';
24 Automake::Location - a class for location tracking, with a stack of contexts
28 use Automake::Location;
30 # Create a new Location object
31 my $where = new Automake::Location "foo.c:13";
34 $where->set ("foo.c:14");
36 # Get the location (without context).
37 # Here this should print "foo.c:14"
38 print $where->get, "\n";
40 # Push a context, and change the location
41 $where->push_context ("included from here");
42 $where->set ("bar.h:1");
44 # Print the location and the stack of context (for debugging)
48 # foo.c:14: included from here
50 # Get the contexts (list of [$location_string, $description])
51 for my $pair (reverse $where->contexts)
53 my ($loc, $descr) = @{$pair};
57 # Pop a context, and reset the location to the previous context.
60 # Clone a Location. Use this when storing the state of a location
61 # that would otherwise be modified.
62 my $where_copy = $where->clone;
64 # Serialize a Location object (for passing through a thread queue,
66 my @array = $where->serialize ();
68 # De-serialize: recreate a Location object from a queue.
69 my $where = new Automake::Location::deserialize ($queue);
73 C<Location> objects are used to keep track of locations in Automake,
74 and used to produce diagnostics.
76 A C<Location> object is made of two parts: a location string, and
79 For instance if C<VAR> is defined at line 1 in F<bar.h> which was
80 included at line 14 in F<foo.c>, then the location string should be
81 C<"bar.h:10"> and the context should be the pair (C<"foo.c:14">,
82 C<"included from here">).
84 Section I<SYNOPSIS> shows how to setup such a C<Location>, and access
85 the location string or the stack of contexts.
87 You can pass a C<Location> to C<Automake::Channels::msg>.
95 =item C<$where = new Automake::Location ([$position])>
97 Create and return a new Location object.
103 my ($class, $position) = @_;
105 position
=> $position,
112 =item C<$location-E<gt>set ($position)>
114 Change the location to be C<$position>.
120 my ($self, $position) = @_;
121 $self->{'position'} = $position;
124 =item C<$location-E<gt>get>
126 Get the location (without context).
133 return $self->{'position'};
136 =item C<$location-E<gt>push_context ($context)>
138 Push a context to the location.
142 sub push_context
($$)
144 my ($self, $context) = @_;
145 push @
{$self->{'contexts'}}, [$self->get, $context];
149 =item C<$where = $location-E<gt>pop_context ($context)>
151 Pop a context, and reset the location to the previous context.
158 my $pair = pop @
{$self->{'contexts'}};
159 $self->set ($pair->[0]);
163 =item C<@contexts = $location-E<gt>get_contexts>
165 Return the array of contexts.
172 return @
{$self->{'contexts'}};
175 =item C<$location = $location-E<gt>clone>
177 Clone a Location. Use this when storing the state of a location
178 that would otherwise be modified.
185 my $other = new Automake
::Location
($self->get);
186 my @contexts = $self->get_contexts;
187 for my $pair (@contexts)
189 push @
{$other->{'contexts'}}, [@
{$pair}];
194 =item C<$res = $location-E<gt>dump>
196 Print the location and the stack of context (for debugging).
203 my $res = ($self->get || 'INTERNAL') . ":\n";
204 for my $pair (reverse $self->get_contexts)
206 $res .= $pair->[0] || 'INTERNAL';
207 $res .= ": $pair->[1]\n";
212 =item C<@array = $location-E<gt>serialize>
214 Serialize a Location object (for passing through a thread queue,
223 push @serial, $self->get;
224 my @contexts = $self->get_contexts;
225 for my $pair (@contexts)
227 push @serial, @
{$pair};
233 =item C<new Automake::Location::deserialize ($queue)>
235 De-serialize: recreate a Location object from a queue.
242 my $position = $queue->dequeue ();
243 my $self = new Automake
::Location
$position;
244 while (my $position = $queue->dequeue ())
246 my $context = $queue->dequeue ();
247 push @
{$self->{'contexts'}}, [$position, $context];
256 L<Automake::Channels>
260 Written by Alexandre Duret-Lutz E<lt>F<adl@gnu.org>E<gt>.