Docs: add some long/short options
[alt-git.git] / perl / Git.pm
blob97e61efaff240a60ecd25ba68d391e75ed7ce958
1 =head1 NAME
3 Git - Perl interface to the Git version control system
5 =cut
8 package Git;
10 use strict;
13 BEGIN {
15 our ($VERSION, @ISA, @EXPORT, @EXPORT_OK);
17 # Totally unstable API.
18 $VERSION = '0.01';
21 =head1 SYNOPSIS
23 use Git;
25 my $version = Git::command_oneline('version');
27 git_cmd_try { Git::command_noisy('update-server-info') }
28 '%s failed w/ code %d';
30 my $repo = Git->repository (Directory => '/srv/git/cogito.git');
33 my @revs = $repo->command('rev-list', '--since=last monday', '--all');
35 my ($fh, $c) = $repo->command_output_pipe('rev-list', '--since=last monday', '--all');
36 my $lastrev = <$fh>; chomp $lastrev;
37 $repo->command_close_pipe($fh, $c);
39 my $lastrev = $repo->command_oneline( [ 'rev-list', '--all' ],
40 STDERR => 0 );
42 my $sha1 = $repo->hash_and_insert_object('file.txt');
43 my $tempfile = tempfile();
44 my $size = $repo->cat_blob($sha1, $tempfile);
46 =cut
49 require Exporter;
51 @ISA = qw(Exporter);
53 @EXPORT = qw(git_cmd_try);
55 # Methods which can be called as standalone functions as well:
56 @EXPORT_OK = qw(command command_oneline command_noisy
57 command_output_pipe command_input_pipe command_close_pipe
58 command_bidi_pipe command_close_bidi_pipe
59 version exec_path hash_object git_cmd_try);
62 =head1 DESCRIPTION
64 This module provides Perl scripts easy way to interface the Git version control
65 system. The modules have an easy and well-tested way to call arbitrary Git
66 commands; in the future, the interface will also provide specialized methods
67 for doing easily operations which are not totally trivial to do over
68 the generic command interface.
70 While some commands can be executed outside of any context (e.g. 'version'
71 or 'init'), most operations require a repository context, which in practice
72 means getting an instance of the Git object using the repository() constructor.
73 (In the future, we will also get a new_repository() constructor.) All commands
74 called as methods of the object are then executed in the context of the
75 repository.
77 Part of the "repository state" is also information about path to the attached
78 working copy (unless you work with a bare repository). You can also navigate
79 inside of the working copy using the C<wc_chdir()> method. (Note that
80 the repository object is self-contained and will not change working directory
81 of your process.)
83 TODO: In the future, we might also do
85 my $remoterepo = $repo->remote_repository (Name => 'cogito', Branch => 'master');
86 $remoterepo ||= Git->remote_repository ('http://git.or.cz/cogito.git/');
87 my @refs = $remoterepo->refs();
89 Currently, the module merely wraps calls to external Git tools. In the future,
90 it will provide a much faster way to interact with Git by linking directly
91 to libgit. This should be completely opaque to the user, though (performance
92 increate nonwithstanding).
94 =cut
97 use Carp qw(carp croak); # but croak is bad - throw instead
98 use Error qw(:try);
99 use Cwd qw(abs_path);
100 use IPC::Open2 qw(open2);
105 =head1 CONSTRUCTORS
107 =over 4
109 =item repository ( OPTIONS )
111 =item repository ( DIRECTORY )
113 =item repository ()
115 Construct a new repository object.
116 C<OPTIONS> are passed in a hash like fashion, using key and value pairs.
117 Possible options are:
119 B<Repository> - Path to the Git repository.
121 B<WorkingCopy> - Path to the associated working copy; not strictly required
122 as many commands will happily crunch on a bare repository.
124 B<WorkingSubdir> - Subdirectory in the working copy to work inside.
125 Just left undefined if you do not want to limit the scope of operations.
127 B<Directory> - Path to the Git working directory in its usual setup.
128 The C<.git> directory is searched in the directory and all the parent
129 directories; if found, C<WorkingCopy> is set to the directory containing
130 it and C<Repository> to the C<.git> directory itself. If no C<.git>
131 directory was found, the C<Directory> is assumed to be a bare repository,
132 C<Repository> is set to point at it and C<WorkingCopy> is left undefined.
133 If the C<$GIT_DIR> environment variable is set, things behave as expected
134 as well.
136 You should not use both C<Directory> and either of C<Repository> and
137 C<WorkingCopy> - the results of that are undefined.
139 Alternatively, a directory path may be passed as a single scalar argument
140 to the constructor; it is equivalent to setting only the C<Directory> option
141 field.
143 Calling the constructor with no options whatsoever is equivalent to
144 calling it with C<< Directory => '.' >>. In general, if you are building
145 a standard porcelain command, simply doing C<< Git->repository() >> should
146 do the right thing and setup the object to reflect exactly where the user
147 is right now.
149 =cut
151 sub repository {
152 my $class = shift;
153 my @args = @_;
154 my %opts = ();
155 my $self;
157 if (defined $args[0]) {
158 if ($#args % 2 != 1) {
159 # Not a hash.
160 $#args == 0 or throw Error::Simple("bad usage");
161 %opts = ( Directory => $args[0] );
162 } else {
163 %opts = @args;
167 if (not defined $opts{Repository} and not defined $opts{WorkingCopy}) {
168 $opts{Directory} ||= '.';
171 if ($opts{Directory}) {
172 -d $opts{Directory} or throw Error::Simple("Directory not found: $!");
174 my $search = Git->repository(WorkingCopy => $opts{Directory});
175 my $dir;
176 try {
177 $dir = $search->command_oneline(['rev-parse', '--git-dir'],
178 STDERR => 0);
179 } catch Git::Error::Command with {
180 $dir = undef;
183 if ($dir) {
184 $dir =~ m#^/# or $dir = $opts{Directory} . '/' . $dir;
185 $opts{Repository} = $dir;
187 # If --git-dir went ok, this shouldn't die either.
188 my $prefix = $search->command_oneline('rev-parse', '--show-prefix');
189 $dir = abs_path($opts{Directory}) . '/';
190 if ($prefix) {
191 if (substr($dir, -length($prefix)) ne $prefix) {
192 throw Error::Simple("rev-parse confused me - $dir does not have trailing $prefix");
194 substr($dir, -length($prefix)) = '';
196 $opts{WorkingCopy} = $dir;
197 $opts{WorkingSubdir} = $prefix;
199 } else {
200 # A bare repository? Let's see...
201 $dir = $opts{Directory};
203 unless (-d "$dir/refs" and -d "$dir/objects" and -e "$dir/HEAD") {
204 # Mimick git-rev-parse --git-dir error message:
205 throw Error::Simple('fatal: Not a git repository');
207 my $search = Git->repository(Repository => $dir);
208 try {
209 $search->command('symbolic-ref', 'HEAD');
210 } catch Git::Error::Command with {
211 # Mimick git-rev-parse --git-dir error message:
212 throw Error::Simple('fatal: Not a git repository');
215 $opts{Repository} = abs_path($dir);
218 delete $opts{Directory};
221 $self = { opts => \%opts };
222 bless $self, $class;
225 =back
227 =head1 METHODS
229 =over 4
231 =item command ( COMMAND [, ARGUMENTS... ] )
233 =item command ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
235 Execute the given Git C<COMMAND> (specify it without the 'git-'
236 prefix), optionally with the specified extra C<ARGUMENTS>.
238 The second more elaborate form can be used if you want to further adjust
239 the command execution. Currently, only one option is supported:
241 B<STDERR> - How to deal with the command's error output. By default (C<undef>)
242 it is delivered to the caller's C<STDERR>. A false value (0 or '') will cause
243 it to be thrown away. If you want to process it, you can get it in a filehandle
244 you specify, but you must be extremely careful; if the error output is not
245 very short and you want to read it in the same process as where you called
246 C<command()>, you are set up for a nice deadlock!
248 The method can be called without any instance or on a specified Git repository
249 (in that case the command will be run in the repository context).
251 In scalar context, it returns all the command output in a single string
252 (verbatim).
254 In array context, it returns an array containing lines printed to the
255 command's stdout (without trailing newlines).
257 In both cases, the command's stdin and stderr are the same as the caller's.
259 =cut
261 sub command {
262 my ($fh, $ctx) = command_output_pipe(@_);
264 if (not defined wantarray) {
265 # Nothing to pepper the possible exception with.
266 _cmd_close($fh, $ctx);
268 } elsif (not wantarray) {
269 local $/;
270 my $text = <$fh>;
271 try {
272 _cmd_close($fh, $ctx);
273 } catch Git::Error::Command with {
274 # Pepper with the output:
275 my $E = shift;
276 $E->{'-outputref'} = \$text;
277 throw $E;
279 return $text;
281 } else {
282 my @lines = <$fh>;
283 defined and chomp for @lines;
284 try {
285 _cmd_close($fh, $ctx);
286 } catch Git::Error::Command with {
287 my $E = shift;
288 $E->{'-outputref'} = \@lines;
289 throw $E;
291 return @lines;
296 =item command_oneline ( COMMAND [, ARGUMENTS... ] )
298 =item command_oneline ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
300 Execute the given C<COMMAND> in the same way as command()
301 does but always return a scalar string containing the first line
302 of the command's standard output.
304 =cut
306 sub command_oneline {
307 my ($fh, $ctx) = command_output_pipe(@_);
309 my $line = <$fh>;
310 defined $line and chomp $line;
311 try {
312 _cmd_close($fh, $ctx);
313 } catch Git::Error::Command with {
314 # Pepper with the output:
315 my $E = shift;
316 $E->{'-outputref'} = \$line;
317 throw $E;
319 return $line;
323 =item command_output_pipe ( COMMAND [, ARGUMENTS... ] )
325 =item command_output_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
327 Execute the given C<COMMAND> in the same way as command()
328 does but return a pipe filehandle from which the command output can be
329 read.
331 The function can return C<($pipe, $ctx)> in array context.
332 See C<command_close_pipe()> for details.
334 =cut
336 sub command_output_pipe {
337 _command_common_pipe('-|', @_);
341 =item command_input_pipe ( COMMAND [, ARGUMENTS... ] )
343 =item command_input_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
345 Execute the given C<COMMAND> in the same way as command_output_pipe()
346 does but return an input pipe filehandle instead; the command output
347 is not captured.
349 The function can return C<($pipe, $ctx)> in array context.
350 See C<command_close_pipe()> for details.
352 =cut
354 sub command_input_pipe {
355 _command_common_pipe('|-', @_);
359 =item command_close_pipe ( PIPE [, CTX ] )
361 Close the C<PIPE> as returned from C<command_*_pipe()>, checking
362 whether the command finished successfully. The optional C<CTX> argument
363 is required if you want to see the command name in the error message,
364 and it is the second value returned by C<command_*_pipe()> when
365 called in array context. The call idiom is:
367 my ($fh, $ctx) = $r->command_output_pipe('status');
368 while (<$fh>) { ... }
369 $r->command_close_pipe($fh, $ctx);
371 Note that you should not rely on whatever actually is in C<CTX>;
372 currently it is simply the command name but in future the context might
373 have more complicated structure.
375 =cut
377 sub command_close_pipe {
378 my ($self, $fh, $ctx) = _maybe_self(@_);
379 $ctx ||= '<unknown>';
380 _cmd_close($fh, $ctx);
383 =item command_bidi_pipe ( COMMAND [, ARGUMENTS... ] )
385 Execute the given C<COMMAND> in the same way as command_output_pipe()
386 does but return both an input pipe filehandle and an output pipe filehandle.
388 The function will return return C<($pid, $pipe_in, $pipe_out, $ctx)>.
389 See C<command_close_bidi_pipe()> for details.
391 =cut
393 sub command_bidi_pipe {
394 my ($pid, $in, $out);
395 $pid = open2($in, $out, 'git', @_);
396 return ($pid, $in, $out, join(' ', @_));
399 =item command_close_bidi_pipe ( PID, PIPE_IN, PIPE_OUT [, CTX] )
401 Close the C<PIPE_IN> and C<PIPE_OUT> as returned from C<command_bidi_pipe()>,
402 checking whether the command finished successfully. The optional C<CTX>
403 argument is required if you want to see the command name in the error message,
404 and it is the fourth value returned by C<command_bidi_pipe()>. The call idiom
407 my ($pid, $in, $out, $ctx) = $r->command_bidi_pipe('cat-file --batch-check');
408 print "000000000\n" $out;
409 while (<$in>) { ... }
410 $r->command_close_bidi_pipe($pid, $in, $out, $ctx);
412 Note that you should not rely on whatever actually is in C<CTX>;
413 currently it is simply the command name but in future the context might
414 have more complicated structure.
416 =cut
418 sub command_close_bidi_pipe {
419 my ($pid, $in, $out, $ctx) = @_;
420 foreach my $fh ($in, $out) {
421 unless (close $fh) {
422 if ($!) {
423 carp "error closing pipe: $!";
424 } elsif ($? >> 8) {
425 throw Git::Error::Command($ctx, $? >>8);
430 waitpid $pid, 0;
432 if ($? >> 8) {
433 throw Git::Error::Command($ctx, $? >>8);
438 =item command_noisy ( COMMAND [, ARGUMENTS... ] )
440 Execute the given C<COMMAND> in the same way as command() does but do not
441 capture the command output - the standard output is not redirected and goes
442 to the standard output of the caller application.
444 While the method is called command_noisy(), you might want to as well use
445 it for the most silent Git commands which you know will never pollute your
446 stdout but you want to avoid the overhead of the pipe setup when calling them.
448 The function returns only after the command has finished running.
450 =cut
452 sub command_noisy {
453 my ($self, $cmd, @args) = _maybe_self(@_);
454 _check_valid_cmd($cmd);
456 my $pid = fork;
457 if (not defined $pid) {
458 throw Error::Simple("fork failed: $!");
459 } elsif ($pid == 0) {
460 _cmd_exec($self, $cmd, @args);
462 if (waitpid($pid, 0) > 0 and $?>>8 != 0) {
463 throw Git::Error::Command(join(' ', $cmd, @args), $? >> 8);
468 =item version ()
470 Return the Git version in use.
472 =cut
474 sub version {
475 my $verstr = command_oneline('--version');
476 $verstr =~ s/^git version //;
477 $verstr;
481 =item exec_path ()
483 Return path to the Git sub-command executables (the same as
484 C<git --exec-path>). Useful mostly only internally.
486 =cut
488 sub exec_path { command_oneline('--exec-path') }
491 =item repo_path ()
493 Return path to the git repository. Must be called on a repository instance.
495 =cut
497 sub repo_path { $_[0]->{opts}->{Repository} }
500 =item wc_path ()
502 Return path to the working copy. Must be called on a repository instance.
504 =cut
506 sub wc_path { $_[0]->{opts}->{WorkingCopy} }
509 =item wc_subdir ()
511 Return path to the subdirectory inside of a working copy. Must be called
512 on a repository instance.
514 =cut
516 sub wc_subdir { $_[0]->{opts}->{WorkingSubdir} ||= '' }
519 =item wc_chdir ( SUBDIR )
521 Change the working copy subdirectory to work within. The C<SUBDIR> is
522 relative to the working copy root directory (not the current subdirectory).
523 Must be called on a repository instance attached to a working copy
524 and the directory must exist.
526 =cut
528 sub wc_chdir {
529 my ($self, $subdir) = @_;
530 $self->wc_path()
531 or throw Error::Simple("bare repository");
533 -d $self->wc_path().'/'.$subdir
534 or throw Error::Simple("subdir not found: $!");
535 # Of course we will not "hold" the subdirectory so anyone
536 # can delete it now and we will never know. But at least we tried.
538 $self->{opts}->{WorkingSubdir} = $subdir;
542 =item config ( VARIABLE )
544 Retrieve the configuration C<VARIABLE> in the same manner as C<config>
545 does. In scalar context requires the variable to be set only one time
546 (exception is thrown otherwise), in array context returns allows the
547 variable to be set multiple times and returns all the values.
549 This currently wraps command('config') so it is not so fast.
551 =cut
553 sub config {
554 my ($self, $var) = _maybe_self(@_);
556 try {
557 my @cmd = ('config');
558 unshift @cmd, $self if $self;
559 if (wantarray) {
560 return command(@cmd, '--get-all', $var);
561 } else {
562 return command_oneline(@cmd, '--get', $var);
564 } catch Git::Error::Command with {
565 my $E = shift;
566 if ($E->value() == 1) {
567 # Key not found.
568 return;
569 } else {
570 throw $E;
576 =item config_bool ( VARIABLE )
578 Retrieve the bool configuration C<VARIABLE>. The return value
579 is usable as a boolean in perl (and C<undef> if it's not defined,
580 of course).
582 This currently wraps command('config') so it is not so fast.
584 =cut
586 sub config_bool {
587 my ($self, $var) = _maybe_self(@_);
589 try {
590 my @cmd = ('config', '--bool', '--get', $var);
591 unshift @cmd, $self if $self;
592 my $val = command_oneline(@cmd);
593 return undef unless defined $val;
594 return $val eq 'true';
595 } catch Git::Error::Command with {
596 my $E = shift;
597 if ($E->value() == 1) {
598 # Key not found.
599 return undef;
600 } else {
601 throw $E;
606 =item config_int ( VARIABLE )
608 Retrieve the integer configuration C<VARIABLE>. The return value
609 is simple decimal number. An optional value suffix of 'k', 'm',
610 or 'g' in the config file will cause the value to be multiplied
611 by 1024, 1048576 (1024^2), or 1073741824 (1024^3) prior to output.
612 It would return C<undef> if configuration variable is not defined,
614 This currently wraps command('config') so it is not so fast.
616 =cut
618 sub config_int {
619 my ($self, $var) = _maybe_self(@_);
621 try {
622 my @cmd = ('config', '--int', '--get', $var);
623 unshift @cmd, $self if $self;
624 return command_oneline(@cmd);
625 } catch Git::Error::Command with {
626 my $E = shift;
627 if ($E->value() == 1) {
628 # Key not found.
629 return undef;
630 } else {
631 throw $E;
636 =item get_colorbool ( NAME )
638 Finds if color should be used for NAMEd operation from the configuration,
639 and returns boolean (true for "use color", false for "do not use color").
641 =cut
643 sub get_colorbool {
644 my ($self, $var) = @_;
645 my $stdout_to_tty = (-t STDOUT) ? "true" : "false";
646 my $use_color = $self->command_oneline('config', '--get-colorbool',
647 $var, $stdout_to_tty);
648 return ($use_color eq 'true');
651 =item get_color ( SLOT, COLOR )
653 Finds color for SLOT from the configuration, while defaulting to COLOR,
654 and returns the ANSI color escape sequence:
656 print $repo->get_color("color.interactive.prompt", "underline blue white");
657 print "some text";
658 print $repo->get_color("", "normal");
660 =cut
662 sub get_color {
663 my ($self, $slot, $default) = @_;
664 my $color = $self->command_oneline('config', '--get-color', $slot, $default);
665 if (!defined $color) {
666 $color = "";
668 return $color;
671 =item ident ( TYPE | IDENTSTR )
673 =item ident_person ( TYPE | IDENTSTR | IDENTARRAY )
675 This suite of functions retrieves and parses ident information, as stored
676 in the commit and tag objects or produced by C<var GIT_type_IDENT> (thus
677 C<TYPE> can be either I<author> or I<committer>; case is insignificant).
679 The C<ident> method retrieves the ident information from C<git-var>
680 and either returns it as a scalar string or as an array with the fields parsed.
681 Alternatively, it can take a prepared ident string (e.g. from the commit
682 object) and just parse it.
684 C<ident_person> returns the person part of the ident - name and email;
685 it can take the same arguments as C<ident> or the array returned by C<ident>.
687 The synopsis is like:
689 my ($name, $email, $time_tz) = ident('author');
690 "$name <$email>" eq ident_person('author');
691 "$name <$email>" eq ident_person($name);
692 $time_tz =~ /^\d+ [+-]\d{4}$/;
694 =cut
696 sub ident {
697 my ($self, $type) = _maybe_self(@_);
698 my $identstr;
699 if (lc $type eq lc 'committer' or lc $type eq lc 'author') {
700 my @cmd = ('var', 'GIT_'.uc($type).'_IDENT');
701 unshift @cmd, $self if $self;
702 $identstr = command_oneline(@cmd);
703 } else {
704 $identstr = $type;
706 if (wantarray) {
707 return $identstr =~ /^(.*) <(.*)> (\d+ [+-]\d{4})$/;
708 } else {
709 return $identstr;
713 sub ident_person {
714 my ($self, @ident) = _maybe_self(@_);
715 $#ident == 0 and @ident = $self ? $self->ident($ident[0]) : ident($ident[0]);
716 return "$ident[0] <$ident[1]>";
720 =item hash_object ( TYPE, FILENAME )
722 Compute the SHA1 object id of the given C<FILENAME> considering it is
723 of the C<TYPE> object type (C<blob>, C<commit>, C<tree>).
725 The method can be called without any instance or on a specified Git repository,
726 it makes zero difference.
728 The function returns the SHA1 hash.
730 =cut
732 # TODO: Support for passing FILEHANDLE instead of FILENAME
733 sub hash_object {
734 my ($self, $type, $file) = _maybe_self(@_);
735 command_oneline('hash-object', '-t', $type, $file);
739 =item hash_and_insert_object ( FILENAME )
741 Compute the SHA1 object id of the given C<FILENAME> and add the object to the
742 object database.
744 The function returns the SHA1 hash.
746 =cut
748 # TODO: Support for passing FILEHANDLE instead of FILENAME
749 sub hash_and_insert_object {
750 my ($self, $filename) = @_;
752 carp "Bad filename \"$filename\"" if $filename =~ /[\r\n]/;
754 $self->_open_hash_and_insert_object_if_needed();
755 my ($in, $out) = ($self->{hash_object_in}, $self->{hash_object_out});
757 unless (print $out $filename, "\n") {
758 $self->_close_hash_and_insert_object();
759 throw Error::Simple("out pipe went bad");
762 chomp(my $hash = <$in>);
763 unless (defined($hash)) {
764 $self->_close_hash_and_insert_object();
765 throw Error::Simple("in pipe went bad");
768 return $hash;
771 sub _open_hash_and_insert_object_if_needed {
772 my ($self) = @_;
774 return if defined($self->{hash_object_pid});
776 ($self->{hash_object_pid}, $self->{hash_object_in},
777 $self->{hash_object_out}, $self->{hash_object_ctx}) =
778 command_bidi_pipe(qw(hash-object -w --stdin-paths));
781 sub _close_hash_and_insert_object {
782 my ($self) = @_;
784 return unless defined($self->{hash_object_pid});
786 my @vars = map { 'hash_object_' . $_ } qw(pid in out ctx);
788 command_close_bidi_pipe($self->{@vars});
789 delete $self->{@vars};
792 =item cat_blob ( SHA1, FILEHANDLE )
794 Prints the contents of the blob identified by C<SHA1> to C<FILEHANDLE> and
795 returns the number of bytes printed.
797 =cut
799 sub cat_blob {
800 my ($self, $sha1, $fh) = @_;
802 $self->_open_cat_blob_if_needed();
803 my ($in, $out) = ($self->{cat_blob_in}, $self->{cat_blob_out});
805 unless (print $out $sha1, "\n") {
806 $self->_close_cat_blob();
807 throw Error::Simple("out pipe went bad");
810 my $description = <$in>;
811 if ($description =~ / missing$/) {
812 carp "$sha1 doesn't exist in the repository";
813 return -1;
816 if ($description !~ /^[0-9a-fA-F]{40} \S+ (\d+)$/) {
817 carp "Unexpected result returned from git cat-file";
818 return -1;
821 my $size = $1;
823 my $blob;
824 my $bytesRead = 0;
826 while (1) {
827 my $bytesLeft = $size - $bytesRead;
828 last unless $bytesLeft;
830 my $bytesToRead = $bytesLeft < 1024 ? $bytesLeft : 1024;
831 my $read = read($in, $blob, $bytesToRead, $bytesRead);
832 unless (defined($read)) {
833 $self->_close_cat_blob();
834 throw Error::Simple("in pipe went bad");
837 $bytesRead += $read;
840 # Skip past the trailing newline.
841 my $newline;
842 my $read = read($in, $newline, 1);
843 unless (defined($read)) {
844 $self->_close_cat_blob();
845 throw Error::Simple("in pipe went bad");
847 unless ($read == 1 && $newline eq "\n") {
848 $self->_close_cat_blob();
849 throw Error::Simple("didn't find newline after blob");
852 unless (print $fh $blob) {
853 $self->_close_cat_blob();
854 throw Error::Simple("couldn't write to passed in filehandle");
857 return $size;
860 sub _open_cat_blob_if_needed {
861 my ($self) = @_;
863 return if defined($self->{cat_blob_pid});
865 ($self->{cat_blob_pid}, $self->{cat_blob_in},
866 $self->{cat_blob_out}, $self->{cat_blob_ctx}) =
867 command_bidi_pipe(qw(cat-file --batch));
870 sub _close_cat_blob {
871 my ($self) = @_;
873 return unless defined($self->{cat_blob_pid});
875 my @vars = map { 'cat_blob_' . $_ } qw(pid in out ctx);
877 command_close_bidi_pipe($self->{@vars});
878 delete $self->{@vars};
881 =back
883 =head1 ERROR HANDLING
885 All functions are supposed to throw Perl exceptions in case of errors.
886 See the L<Error> module on how to catch those. Most exceptions are mere
887 L<Error::Simple> instances.
889 However, the C<command()>, C<command_oneline()> and C<command_noisy()>
890 functions suite can throw C<Git::Error::Command> exceptions as well: those are
891 thrown when the external command returns an error code and contain the error
892 code as well as access to the captured command's output. The exception class
893 provides the usual C<stringify> and C<value> (command's exit code) methods and
894 in addition also a C<cmd_output> method that returns either an array or a
895 string with the captured command output (depending on the original function
896 call context; C<command_noisy()> returns C<undef>) and $<cmdline> which
897 returns the command and its arguments (but without proper quoting).
899 Note that the C<command_*_pipe()> functions cannot throw this exception since
900 it has no idea whether the command failed or not. You will only find out
901 at the time you C<close> the pipe; if you want to have that automated,
902 use C<command_close_pipe()>, which can throw the exception.
904 =cut
907 package Git::Error::Command;
909 @Git::Error::Command::ISA = qw(Error);
911 sub new {
912 my $self = shift;
913 my $cmdline = '' . shift;
914 my $value = 0 + shift;
915 my $outputref = shift;
916 my(@args) = ();
918 local $Error::Depth = $Error::Depth + 1;
920 push(@args, '-cmdline', $cmdline);
921 push(@args, '-value', $value);
922 push(@args, '-outputref', $outputref);
924 $self->SUPER::new(-text => 'command returned error', @args);
927 sub stringify {
928 my $self = shift;
929 my $text = $self->SUPER::stringify;
930 $self->cmdline() . ': ' . $text . ': ' . $self->value() . "\n";
933 sub cmdline {
934 my $self = shift;
935 $self->{'-cmdline'};
938 sub cmd_output {
939 my $self = shift;
940 my $ref = $self->{'-outputref'};
941 defined $ref or undef;
942 if (ref $ref eq 'ARRAY') {
943 return @$ref;
944 } else { # SCALAR
945 return $$ref;
950 =over 4
952 =item git_cmd_try { CODE } ERRMSG
954 This magical statement will automatically catch any C<Git::Error::Command>
955 exceptions thrown by C<CODE> and make your program die with C<ERRMSG>
956 on its lips; the message will have %s substituted for the command line
957 and %d for the exit status. This statement is useful mostly for producing
958 more user-friendly error messages.
960 In case of no exception caught the statement returns C<CODE>'s return value.
962 Note that this is the only auto-exported function.
964 =cut
966 sub git_cmd_try(&$) {
967 my ($code, $errmsg) = @_;
968 my @result;
969 my $err;
970 my $array = wantarray;
971 try {
972 if ($array) {
973 @result = &$code;
974 } else {
975 $result[0] = &$code;
977 } catch Git::Error::Command with {
978 my $E = shift;
979 $err = $errmsg;
980 $err =~ s/\%s/$E->cmdline()/ge;
981 $err =~ s/\%d/$E->value()/ge;
982 # We can't croak here since Error.pm would mangle
983 # that to Error::Simple.
985 $err and croak $err;
986 return $array ? @result : $result[0];
990 =back
992 =head1 COPYRIGHT
994 Copyright 2006 by Petr Baudis E<lt>pasky@suse.czE<gt>.
996 This module is free software; it may be used, copied, modified
997 and distributed under the terms of the GNU General Public Licence,
998 either version 2, or (at your option) any later version.
1000 =cut
1003 # Take raw method argument list and return ($obj, @args) in case
1004 # the method was called upon an instance and (undef, @args) if
1005 # it was called directly.
1006 sub _maybe_self {
1007 # This breaks inheritance. Oh well.
1008 ref $_[0] eq 'Git' ? @_ : (undef, @_);
1011 # Check if the command id is something reasonable.
1012 sub _check_valid_cmd {
1013 my ($cmd) = @_;
1014 $cmd =~ /^[a-z0-9A-Z_-]+$/ or throw Error::Simple("bad command: $cmd");
1017 # Common backend for the pipe creators.
1018 sub _command_common_pipe {
1019 my $direction = shift;
1020 my ($self, @p) = _maybe_self(@_);
1021 my (%opts, $cmd, @args);
1022 if (ref $p[0]) {
1023 ($cmd, @args) = @{shift @p};
1024 %opts = ref $p[0] ? %{$p[0]} : @p;
1025 } else {
1026 ($cmd, @args) = @p;
1028 _check_valid_cmd($cmd);
1030 my $fh;
1031 if ($^O eq 'MSWin32') {
1032 # ActiveState Perl
1033 #defined $opts{STDERR} and
1034 # warn 'ignoring STDERR option - running w/ ActiveState';
1035 $direction eq '-|' or
1036 die 'input pipe for ActiveState not implemented';
1037 # the strange construction with *ACPIPE is just to
1038 # explain the tie below that we want to bind to
1039 # a handle class, not scalar. It is not known if
1040 # it is something specific to ActiveState Perl or
1041 # just a Perl quirk.
1042 tie (*ACPIPE, 'Git::activestate_pipe', $cmd, @args);
1043 $fh = *ACPIPE;
1045 } else {
1046 my $pid = open($fh, $direction);
1047 if (not defined $pid) {
1048 throw Error::Simple("open failed: $!");
1049 } elsif ($pid == 0) {
1050 if (defined $opts{STDERR}) {
1051 close STDERR;
1053 if ($opts{STDERR}) {
1054 open (STDERR, '>&', $opts{STDERR})
1055 or die "dup failed: $!";
1057 _cmd_exec($self, $cmd, @args);
1060 return wantarray ? ($fh, join(' ', $cmd, @args)) : $fh;
1063 # When already in the subprocess, set up the appropriate state
1064 # for the given repository and execute the git command.
1065 sub _cmd_exec {
1066 my ($self, @args) = @_;
1067 if ($self) {
1068 $self->repo_path() and $ENV{'GIT_DIR'} = $self->repo_path();
1069 $self->wc_path() and chdir($self->wc_path());
1070 $self->wc_subdir() and chdir($self->wc_subdir());
1072 _execv_git_cmd(@args);
1073 die qq[exec "@args" failed: $!];
1076 # Execute the given Git command ($_[0]) with arguments ($_[1..])
1077 # by searching for it at proper places.
1078 sub _execv_git_cmd { exec('git', @_); }
1080 # Close pipe to a subprocess.
1081 sub _cmd_close {
1082 my ($fh, $ctx) = @_;
1083 if (not close $fh) {
1084 if ($!) {
1085 # It's just close, no point in fatalities
1086 carp "error closing pipe: $!";
1087 } elsif ($? >> 8) {
1088 # The caller should pepper this.
1089 throw Git::Error::Command($ctx, $? >> 8);
1091 # else we might e.g. closed a live stream; the command
1092 # dying of SIGPIPE would drive us here.
1097 sub DESTROY {
1098 my ($self) = @_;
1099 $self->_close_hash_and_insert_object();
1100 $self->_close_cat_blob();
1104 # Pipe implementation for ActiveState Perl.
1106 package Git::activestate_pipe;
1107 use strict;
1109 sub TIEHANDLE {
1110 my ($class, @params) = @_;
1111 # FIXME: This is probably horrible idea and the thing will explode
1112 # at the moment you give it arguments that require some quoting,
1113 # but I have no ActiveState clue... --pasky
1114 # Let's just hope ActiveState Perl does at least the quoting
1115 # correctly.
1116 my @data = qx{git @params};
1117 bless { i => 0, data => \@data }, $class;
1120 sub READLINE {
1121 my $self = shift;
1122 if ($self->{i} >= scalar @{$self->{data}}) {
1123 return undef;
1125 my $i = $self->{i};
1126 if (wantarray) {
1127 $self->{i} = $#{$self->{'data'}} + 1;
1128 return splice(@{$self->{'data'}}, $i);
1130 $self->{i} = $i + 1;
1131 return $self->{'data'}->[ $i ];
1134 sub CLOSE {
1135 my $self = shift;
1136 delete $self->{data};
1137 delete $self->{i};
1140 sub EOF {
1141 my $self = shift;
1142 return ($self->{i} >= scalar @{$self->{data}});
1146 1; # Famous last words