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+=head1 NAME
+
+Git - Perl interface to the Git version control system
+
+=cut
+
+
+package Git;
+
+use strict;
+
+
+BEGIN {
+
+our ($VERSION, @ISA, @EXPORT, @EXPORT_OK);
+
+# Totally unstable API.
+$VERSION = '0.01';
+
+
+=head1 SYNOPSIS
+
+ use Git;
+
+ my $version = Git::command_oneline('version');
+
+ git_cmd_try { Git::command_noisy('update-server-info') }
+ '%s failed w/ code %d';
+
+ my $repo = Git->repository (Directory => '/srv/git/cogito.git');
+
+
+ my @revs = $repo->command('rev-list', '--since=last monday', '--all');
+
+ my ($fh, $c) = $repo->command_output_pipe('rev-list', '--since=last monday', '--all');
+ my $lastrev = <$fh>; chomp $lastrev;
+ $repo->command_close_pipe($fh, $c);
+
+ my $lastrev = $repo->command_oneline( [ 'rev-list', '--all' ],
+ STDERR => 0 );
+
+=cut
+
+
+require Exporter;
+
+@ISA = qw(Exporter);
+
+@EXPORT = qw(git_cmd_try);
+
+# Methods which can be called as standalone functions as well:
+@EXPORT_OK = qw(command command_oneline command_noisy
+ command_output_pipe command_input_pipe command_close_pipe
+ version exec_path hash_object git_cmd_try);
+
+
+=head1 DESCRIPTION
+
+This module provides Perl scripts easy way to interface the Git version control
+system. The modules have an easy and well-tested way to call arbitrary Git
+commands; in the future, the interface will also provide specialized methods
+for doing easily operations which are not totally trivial to do over
+the generic command interface.
+
+While some commands can be executed outside of any context (e.g. 'version'
+or 'init'), most operations require a repository context, which in practice
+means getting an instance of the Git object using the repository() constructor.
+(In the future, we will also get a new_repository() constructor.) All commands
+called as methods of the object are then executed in the context of the
+repository.
+
+Part of the "repository state" is also information about path to the attached
+working copy (unless you work with a bare repository). You can also navigate
+inside of the working copy using the C<wc_chdir()> method. (Note that
+the repository object is self-contained and will not change working directory
+of your process.)
+
+TODO: In the future, we might also do
+
+ my $remoterepo = $repo->remote_repository (Name => 'cogito', Branch => 'master');
+ $remoterepo ||= Git->remote_repository ('http://git.or.cz/cogito.git/');
+ my @refs = $remoterepo->refs();
+
+Currently, the module merely wraps calls to external Git tools. In the future,
+it will provide a much faster way to interact with Git by linking directly
+to libgit. This should be completely opaque to the user, though (performance
+increate nonwithstanding).
+
+=cut
+
+
+use Carp qw(carp croak); # but croak is bad - throw instead
+use Error qw(:try);
+use Cwd qw(abs_path);
+
+}
+
+
+=head1 CONSTRUCTORS
+
+=over 4
+
+=item repository ( OPTIONS )
+
+=item repository ( DIRECTORY )
+
+=item repository ()
+
+Construct a new repository object.
+C<OPTIONS> are passed in a hash like fashion, using key and value pairs.
+Possible options are:
+
+B<Repository> - Path to the Git repository.
+
+B<WorkingCopy> - Path to the associated working copy; not strictly required
+as many commands will happily crunch on a bare repository.
+
+B<WorkingSubdir> - Subdirectory in the working copy to work inside.
+Just left undefined if you do not want to limit the scope of operations.
+
+B<Directory> - Path to the Git working directory in its usual setup.
+The C<.git> directory is searched in the directory and all the parent
+directories; if found, C<WorkingCopy> is set to the directory containing
+it and C<Repository> to the C<.git> directory itself. If no C<.git>
+directory was found, the C<Directory> is assumed to be a bare repository,
+C<Repository> is set to point at it and C<WorkingCopy> is left undefined.
+If the C<$GIT_DIR> environment variable is set, things behave as expected
+as well.
+
+You should not use both C<Directory> and either of C<Repository> and
+C<WorkingCopy> - the results of that are undefined.
+
+Alternatively, a directory path may be passed as a single scalar argument
+to the constructor; it is equivalent to setting only the C<Directory> option
+field.
+
+Calling the constructor with no options whatsoever is equivalent to
+calling it with C<< Directory => '.' >>. In general, if you are building
+a standard porcelain command, simply doing C<< Git->repository() >> should
+do the right thing and setup the object to reflect exactly where the user
+is right now.
+
+=cut
+
+sub repository {
+ my $class = shift;
+ my @args = @_;
+ my %opts = ();
+ my $self;
+
+ if (defined $args[0]) {
+ if ($#args % 2 != 1) {
+ # Not a hash.
+ $#args == 0 or throw Error::Simple("bad usage");
+ %opts = ( Directory => $args[0] );
+ } else {
+ %opts = @args;
+ }
+ }
+
+ if (not defined $opts{Repository} and not defined $opts{WorkingCopy}) {
+ $opts{Directory} ||= '.';
+ }
+
+ if ($opts{Directory}) {
+ -d $opts{Directory} or throw Error::Simple("Directory not found: $!");
+
+ my $search = Git->repository(WorkingCopy => $opts{Directory});
+ my $dir;
+ try {
+ $dir = $search->command_oneline(['rev-parse', '--git-dir'],
+ STDERR => 0);
+ } catch Git::Error::Command with {
+ $dir = undef;
+ };
+
+ if ($dir) {
+ $dir =~ m#^/# or $dir = $opts{Directory} . '/' . $dir;
+ $opts{Repository} = $dir;
+
+ # If --git-dir went ok, this shouldn't die either.
+ my $prefix = $search->command_oneline('rev-parse', '--show-prefix');
+ $dir = abs_path($opts{Directory}) . '/';
+ if ($prefix) {
+ if (substr($dir, -length($prefix)) ne $prefix) {
+ throw Error::Simple("rev-parse confused me - $dir does not have trailing $prefix");
+ }
+ substr($dir, -length($prefix)) = '';
+ }
+ $opts{WorkingCopy} = $dir;
+ $opts{WorkingSubdir} = $prefix;
+
+ } else {
+ # A bare repository? Let's see...
+ $dir = $opts{Directory};
+
+ unless (-d "$dir/refs" and -d "$dir/objects" and -e "$dir/HEAD") {
+ # Mimick git-rev-parse --git-dir error message:
+ throw Error::Simple('fatal: Not a git repository');
+ }
+ my $search = Git->repository(Repository => $dir);
+ try {
+ $search->command('symbolic-ref', 'HEAD');
+ } catch Git::Error::Command with {
+ # Mimick git-rev-parse --git-dir error message:
+ throw Error::Simple('fatal: Not a git repository');
+ }
+
+ $opts{Repository} = abs_path($dir);
+ }
+
+ delete $opts{Directory};
+ }
+
+ $self = { opts => \%opts };
+ bless $self, $class;
+}
+
+
+=back
+
+=head1 METHODS
+
+=over 4
+
+=item command ( COMMAND [, ARGUMENTS... ] )
+
+=item command ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
+
+Execute the given Git C<COMMAND> (specify it without the 'git-'
+prefix), optionally with the specified extra C<ARGUMENTS>.
+
+The second more elaborate form can be used if you want to further adjust
+the command execution. Currently, only one option is supported:
+
+B<STDERR> - How to deal with the command's error output. By default (C<undef>)
+it is delivered to the caller's C<STDERR>. A false value (0 or '') will cause
+it to be thrown away. If you want to process it, you can get it in a filehandle
+you specify, but you must be extremely careful; if the error output is not
+very short and you want to read it in the same process as where you called
+C<command()>, you are set up for a nice deadlock!
+
+The method can be called without any instance or on a specified Git repository
+(in that case the command will be run in the repository context).
+
+In scalar context, it returns all the command output in a single string
+(verbatim).
+
+In array context, it returns an array containing lines printed to the
+command's stdout (without trailing newlines).
+
+In both cases, the command's stdin and stderr are the same as the caller's.
+
+=cut
+
+sub command {
+ my ($fh, $ctx) = command_output_pipe(@_);
+
+ if (not defined wantarray) {
+ # Nothing to pepper the possible exception with.
+ _cmd_close($fh, $ctx);
+
+ } elsif (not wantarray) {
+ local $/;
+ my $text = <$fh>;
+ try {
+ _cmd_close($fh, $ctx);
+ } catch Git::Error::Command with {
+ # Pepper with the output:
+ my $E = shift;
+ $E->{'-outputref'} = \$text;
+ throw $E;
+ };
+ return $text;
+
+ } else {
+ my @lines = <$fh>;
+ defined and chomp for @lines;
+ try {
+ _cmd_close($fh, $ctx);
+ } catch Git::Error::Command with {
+ my $E = shift;
+ $E->{'-outputref'} = \@lines;
+ throw $E;
+ };
+ return @lines;
+ }
+}
+
+
+=item command_oneline ( COMMAND [, ARGUMENTS... ] )
+
+=item command_oneline ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
+
+Execute the given C<COMMAND> in the same way as command()
+does but always return a scalar string containing the first line
+of the command's standard output.
+
+=cut
+
+sub command_oneline {
+ my ($fh, $ctx) = command_output_pipe(@_);
+
+ my $line = <$fh>;
+ defined $line and chomp $line;
+ try {
+ _cmd_close($fh, $ctx);
+ } catch Git::Error::Command with {
+ # Pepper with the output:
+ my $E = shift;
+ $E->{'-outputref'} = \$line;
+ throw $E;
+ };
+ return $line;
+}
+
+
+=item command_output_pipe ( COMMAND [, ARGUMENTS... ] )
+
+=item command_output_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
+
+Execute the given C<COMMAND> in the same way as command()
+does but return a pipe filehandle from which the command output can be
+read.
+
+The function can return C<($pipe, $ctx)> in array context.
+See C<command_close_pipe()> for details.
+
+=cut
+
+sub command_output_pipe {
+ _command_common_pipe('-|', @_);
+}
+
+
+=item command_input_pipe ( COMMAND [, ARGUMENTS... ] )
+
+=item command_input_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
+
+Execute the given C<COMMAND> in the same way as command_output_pipe()
+does but return an input pipe filehandle instead; the command output
+is not captured.
+
+The function can return C<($pipe, $ctx)> in array context.
+See C<command_close_pipe()> for details.
+
+=cut
+
+sub command_input_pipe {
+ _command_common_pipe('|-', @_);
+}
+
+
+=item command_close_pipe ( PIPE [, CTX ] )
+
+Close the C<PIPE> as returned from C<command_*_pipe()>, checking
+whether the command finished successfully. The optional C<CTX> argument
+is required if you want to see the command name in the error message,
+and it is the second value returned by C<command_*_pipe()> when
+called in array context. The call idiom is:
+
+ my ($fh, $ctx) = $r->command_output_pipe('status');
+ while (<$fh>) { ... }
+ $r->command_close_pipe($fh, $ctx);
+
+Note that you should not rely on whatever actually is in C<CTX>;
+currently it is simply the command name but in future the context might
+have more complicated structure.
+
+=cut
+
+sub command_close_pipe {
+ my ($self, $fh, $ctx) = _maybe_self(@_);
+ $ctx ||= '<unknown>';
+ _cmd_close($fh, $ctx);
+}
+
+
+=item command_noisy ( COMMAND [, ARGUMENTS... ] )
+
+Execute the given C<COMMAND> in the same way as command() does but do not
+capture the command output - the standard output is not redirected and goes
+to the standard output of the caller application.
+
+While the method is called command_noisy(), you might want to as well use
+it for the most silent Git commands which you know will never pollute your
+stdout but you want to avoid the overhead of the pipe setup when calling them.
+
+The function returns only after the command has finished running.
+
+=cut
+
+sub command_noisy {
+ my ($self, $cmd, @args) = _maybe_self(@_);
+ _check_valid_cmd($cmd);
+
+ my $pid = fork;
+ if (not defined $pid) {
+ throw Error::Simple("fork failed: $!");
+ } elsif ($pid == 0) {
+ _cmd_exec($self, $cmd, @args);
+ }
+ if (waitpid($pid, 0) > 0 and $?>>8 != 0) {
+ throw Git::Error::Command(join(' ', $cmd, @args), $? >> 8);
+ }
+}
+
+
+=item version ()
+
+Return the Git version in use.
+
+=cut
+
+sub version {
+ my $verstr = command_oneline('--version');
+ $verstr =~ s/^git version //;
+ $verstr;
+}
+
+
+=item exec_path ()
+
+Return path to the Git sub-command executables (the same as
+C<git --exec-path>). Useful mostly only internally.
+
+=cut
+
+sub exec_path { command_oneline('--exec-path') }
+
+
+=item repo_path ()
+
+Return path to the git repository. Must be called on a repository instance.
+
+=cut
+
+sub repo_path { $_[0]->{opts}->{Repository} }
+
+
+=item wc_path ()
+
+Return path to the working copy. Must be called on a repository instance.
+
+=cut
+
+sub wc_path { $_[0]->{opts}->{WorkingCopy} }
+
+
+=item wc_subdir ()
+
+Return path to the subdirectory inside of a working copy. Must be called
+on a repository instance.
+
+=cut
+
+sub wc_subdir { $_[0]->{opts}->{WorkingSubdir} ||= '' }
+
+
+=item wc_chdir ( SUBDIR )
+
+Change the working copy subdirectory to work within. The C<SUBDIR> is
+relative to the working copy root directory (not the current subdirectory).
+Must be called on a repository instance attached to a working copy
+and the directory must exist.
+
+=cut
+
+sub wc_chdir {
+ my ($self, $subdir) = @_;
+ $self->wc_path()
+ or throw Error::Simple("bare repository");
+
+ -d $self->wc_path().'/'.$subdir
+ or throw Error::Simple("subdir not found: $!");
+ # Of course we will not "hold" the subdirectory so anyone
+ # can delete it now and we will never know. But at least we tried.
+
+ $self->{opts}->{WorkingSubdir} = $subdir;
+}
+
+
+=item config ( VARIABLE )
+
+Retrieve the configuration C<VARIABLE> in the same manner as C<config>
+does. In scalar context requires the variable to be set only one time
+(exception is thrown otherwise), in array context returns allows the
+variable to be set multiple times and returns all the values.
+
+Must be called on a repository instance.
+
+This currently wraps command('config') so it is not so fast.
+
+=cut
+
+sub config {
+ my ($self, $var) = @_;
+ $self->repo_path()
+ or throw Error::Simple("not a repository");
+
+ try {
+ if (wantarray) {
+ return $self->command('config', '--get-all', $var);
+ } else {
+ return $self->command_oneline('config', '--get', $var);
+ }
+ } catch Git::Error::Command with {
+ my $E = shift;
+ if ($E->value() == 1) {
+ # Key not found.
+ return undef;
+ } else {
+ throw $E;
+ }
+ };
+}
+
+
+=item config_bool ( VARIABLE )
+
+Retrieve the bool configuration C<VARIABLE>. The return value
+is usable as a boolean in perl (and C<undef> if it's not defined,
+of course).
+
+Must be called on a repository instance.
+
+This currently wraps command('config') so it is not so fast.
+
+=cut
+
+sub config_bool {
+ my ($self, $var) = @_;
+ $self->repo_path()
+ or throw Error::Simple("not a repository");
+
+ try {
+ my $val = $self->command_oneline('config', '--bool', '--get',
+ $var);
+ return undef unless defined $val;
+ return $val eq 'true';
+ } catch Git::Error::Command with {
+ my $E = shift;
+ if ($E->value() == 1) {
+ # Key not found.
+ return undef;
+ } else {
+ throw $E;
+ }
+ };
+}
+
+
+=item ident ( TYPE | IDENTSTR )
+
+=item ident_person ( TYPE | IDENTSTR | IDENTARRAY )
+
+This suite of functions retrieves and parses ident information, as stored
+in the commit and tag objects or produced by C<var GIT_type_IDENT> (thus
+C<TYPE> can be either I<author> or I<committer>; case is insignificant).
+
+The C<ident> method retrieves the ident information from C<git-var>
+and either returns it as a scalar string or as an array with the fields parsed.
+Alternatively, it can take a prepared ident string (e.g. from the commit
+object) and just parse it.
+
+C<ident_person> returns the person part of the ident - name and email;
+it can take the same arguments as C<ident> or the array returned by C<ident>.
+
+The synopsis is like:
+
+ my ($name, $email, $time_tz) = ident('author');
+ "$name <$email>" eq ident_person('author');
+ "$name <$email>" eq ident_person($name);
+ $time_tz =~ /^\d+ [+-]\d{4}$/;
+
+Both methods must be called on a repository instance.
+
+=cut
+
+sub ident {
+ my ($self, $type) = @_;
+ my $identstr;
+ if (lc $type eq lc 'committer' or lc $type eq lc 'author') {
+ $identstr = $self->command_oneline('var', 'GIT_'.uc($type).'_IDENT');
+ } else {
+ $identstr = $type;
+ }
+ if (wantarray) {
+ return $identstr =~ /^(.*) <(.*)> (\d+ [+-]\d{4})$/;
+ } else {
+ return $identstr;
+ }
+}
+
+sub ident_person {
+ my ($self, @ident) = @_;
+ $#ident == 0 and @ident = $self->ident($ident[0]);
+ return "$ident[0] <$ident[1]>";
+}
+
+
+=item hash_object ( TYPE, FILENAME )
+
+Compute the SHA1 object id of the given C<FILENAME> (or data waiting in
+C<FILEHANDLE>) considering it is of the C<TYPE> object type (C<blob>,
+C<commit>, C<tree>).
+
+The method can be called without any instance or on a specified Git repository,
+it makes zero difference.
+
+The function returns the SHA1 hash.
+
+=cut
+
+# TODO: Support for passing FILEHANDLE instead of FILENAME
+sub hash_object {
+ my ($self, $type, $file) = _maybe_self(@_);
+ command_oneline('hash-object', '-t', $type, $file);
+}
+
+
+
+=back
+
+=head1 ERROR HANDLING
+
+All functions are supposed to throw Perl exceptions in case of errors.
+See the L<Error> module on how to catch those. Most exceptions are mere
+L<Error::Simple> instances.
+
+However, the C<command()>, C<command_oneline()> and C<command_noisy()>
+functions suite can throw C<Git::Error::Command> exceptions as well: those are
+thrown when the external command returns an error code and contain the error
+code as well as access to the captured command's output. The exception class
+provides the usual C<stringify> and C<value> (command's exit code) methods and
+in addition also a C<cmd_output> method that returns either an array or a
+string with the captured command output (depending on the original function
+call context; C<command_noisy()> returns C<undef>) and $<cmdline> which
+returns the command and its arguments (but without proper quoting).
+
+Note that the C<command_*_pipe()> functions cannot throw this exception since
+it has no idea whether the command failed or not. You will only find out
+at the time you C<close> the pipe; if you want to have that automated,
+use C<command_close_pipe()>, which can throw the exception.
+
+=cut
+
+{
+ package Git::Error::Command;
+
+ @Git::Error::Command::ISA = qw(Error);
+
+ sub new {
+ my $self = shift;
+ my $cmdline = '' . shift;
+ my $value = 0 + shift;
+ my $outputref = shift;
+ my(@args) = ();
+
+ local $Error::Depth = $Error::Depth + 1;
+
+ push(@args, '-cmdline', $cmdline);
+ push(@args, '-value', $value);
+ push(@args, '-outputref', $outputref);
+
+ $self->SUPER::new(-text => 'command returned error', @args);
+ }
+
+ sub stringify {
+ my $self = shift;
+ my $text = $self->SUPER::stringify;
+ $self->cmdline() . ': ' . $text . ': ' . $self->value() . "\n";
+ }
+
+ sub cmdline {
+ my $self = shift;
+ $self->{'-cmdline'};
+ }
+
+ sub cmd_output {
+ my $self = shift;
+ my $ref = $self->{'-outputref'};
+ defined $ref or undef;
+ if (ref $ref eq 'ARRAY') {
+ return @$ref;
+ } else { # SCALAR
+ return $$ref;
+ }
+ }
+}
+
+=over 4
+
+=item git_cmd_try { CODE } ERRMSG
+
+This magical statement will automatically catch any C<Git::Error::Command>
+exceptions thrown by C<CODE> and make your program die with C<ERRMSG>
+on its lips; the message will have %s substituted for the command line
+and %d for the exit status. This statement is useful mostly for producing
+more user-friendly error messages.
+
+In case of no exception caught the statement returns C<CODE>'s return value.
+
+Note that this is the only auto-exported function.
+
+=cut
+
+sub git_cmd_try(&$) {
+ my ($code, $errmsg) = @_;
+ my @result;
+ my $err;
+ my $array = wantarray;
+ try {
+ if ($array) {
+ @result = &$code;
+ } else {
+ $result[0] = &$code;
+ }
+ } catch Git::Error::Command with {
+ my $E = shift;
+ $err = $errmsg;
+ $err =~ s/\%s/$E->cmdline()/ge;
+ $err =~ s/\%d/$E->value()/ge;
+ # We can't croak here since Error.pm would mangle
+ # that to Error::Simple.
+ };
+ $err and croak $err;
+ return $array ? @result : $result[0];
+}
+
+
+=back
+
+=head1 COPYRIGHT
+
+Copyright 2006 by Petr Baudis E<lt>pasky@suse.czE<gt>.
+
+This module is free software; it may be used, copied, modified
+and distributed under the terms of the GNU General Public Licence,
+either version 2, or (at your option) any later version.
+
+=cut
+
+
+# Take raw method argument list and return ($obj, @args) in case
+# the method was called upon an instance and (undef, @args) if
+# it was called directly.
+sub _maybe_self {
+ # This breaks inheritance. Oh well.
+ ref $_[0] eq 'Git' ? @_ : (undef, @_);
+}
+
+# Check if the command id is something reasonable.
+sub _check_valid_cmd {
+ my ($cmd) = @_;
+ $cmd =~ /^[a-z0-9A-Z_-]+$/ or throw Error::Simple("bad command: $cmd");
+}
+
+# Common backend for the pipe creators.
+sub _command_common_pipe {
+ my $direction = shift;
+ my ($self, @p) = _maybe_self(@_);
+ my (%opts, $cmd, @args);
+ if (ref $p[0]) {
+ ($cmd, @args) = @{shift @p};
+ %opts = ref $p[0] ? %{$p[0]} : @p;
+ } else {
+ ($cmd, @args) = @p;
+ }
+ _check_valid_cmd($cmd);
+
+ my $fh;
+ if ($^O eq 'MSWin32') {
+ # ActiveState Perl
+ #defined $opts{STDERR} and
+ # warn 'ignoring STDERR option - running w/ ActiveState';
+ $direction eq '-|' or
+ die 'input pipe for ActiveState not implemented';
+ # the strange construction with *ACPIPE is just to
+ # explain the tie below that we want to bind to
+ # a handle class, not scalar. It is not known if
+ # it is something specific to ActiveState Perl or
+ # just a Perl quirk.
+ tie (*ACPIPE, 'Git::activestate_pipe', $cmd, @args);
+ $fh = *ACPIPE;
+
+ } else {
+ my $pid = open($fh, $direction);
+ if (not defined $pid) {
+ throw Error::Simple("open failed: $!");
+ } elsif ($pid == 0) {
+ if (defined $opts{STDERR}) {
+ close STDERR;
+ }
+ if ($opts{STDERR}) {
+ open (STDERR, '>&', $opts{STDERR})
+ or die "dup failed: $!";
+ }
+ _cmd_exec($self, $cmd, @args);
+ }
+ }
+ return wantarray ? ($fh, join(' ', $cmd, @args)) : $fh;
+}
+
+# When already in the subprocess, set up the appropriate state
+# for the given repository and execute the git command.
+sub _cmd_exec {
+ my ($self, @args) = @_;
+ if ($self) {
+ $self->repo_path() and $ENV{'GIT_DIR'} = $self->repo_path();
+ $self->wc_path() and chdir($self->wc_path());
+ $self->wc_subdir() and chdir($self->wc_subdir());
+ }
+ _execv_git_cmd(@args);
+ die "exec failed: $!";
+}
+
+# Execute the given Git command ($_[0]) with arguments ($_[1..])
+# by searching for it at proper places.
+sub _execv_git_cmd { exec('git', @_); }
+
+# Close pipe to a subprocess.
+sub _cmd_close {
+ my ($fh, $ctx) = @_;
+ if (not close $fh) {
+ if ($!) {
+ # It's just close, no point in fatalities
+ carp "error closing pipe: $!";
+ } elsif ($? >> 8) {
+ # The caller should pepper this.
+ throw Git::Error::Command($ctx, $? >> 8);
+ }
+ # else we might e.g. closed a live stream; the command
+ # dying of SIGPIPE would drive us here.
+ }
+}
+
+
+sub DESTROY { }
+
+
+# Pipe implementation for ActiveState Perl.
+
+package Git::activestate_pipe;
+use strict;
+
+sub TIEHANDLE {
+ my ($class, @params) = @_;
+ # FIXME: This is probably horrible idea and the thing will explode
+ # at the moment you give it arguments that require some quoting,
+ # but I have no ActiveState clue... --pasky
+ # Let's just hope ActiveState Perl does at least the quoting
+ # correctly.
+ my @data = qx{git @params};
+ bless { i => 0, data => \@data }, $class;
+}
+
+sub READLINE {
+ my $self = shift;
+ if ($self->{i} >= scalar @{$self->{data}}) {
+ return undef;
+ }
+ return $self->{'data'}->[ $self->{i}++ ];
+}
+
+sub CLOSE {
+ my $self = shift;
+ delete $self->{data};
+ delete $self->{i};
+}
+
+sub EOF {
+ my $self = shift;
+ return ($self->{i} >= scalar @{$self->{data}});
+}
+
+
+1; # Famous last words