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diff --git a/perl/Git.pm b/perl/Git.pm
index 212337ee5bfe64bb0479eab01beb073f4f007f89..7bbb5be77e1731bd378307826078843f7785cbc2 100644 (file)
--- a/perl/Git.pm
+++ b/perl/Git.pm
my $version = Git::command_oneline('version');
my $version = Git::command_oneline('version');
- Git::command_noisy('update-server-info');
+ 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 $repo = Git->repository (Directory => '/srv/git/cogito.git');
my @revs = $repo->command('rev-list', '--since=last monday', '--all');
- my $fh = $repo->command_pipe('rev-list', '--since=last monday', '--all');
+ my ($fh, $c) = $repo->command_output_pipe('rev-list', '--since=last monday', '--all');
my $lastrev = <$fh>; chomp $lastrev;
my $lastrev = <$fh>; chomp $lastrev;
- close $fh; # You may want to test rev-list exit status here
+ $repo->command_close_pipe($fh, $c);
- my $lastrev = $repo->command_oneline('rev-list', '--all');
+ my $lastrev = $repo->command_oneline( [ 'rev-list', '--all' ],
+ STDERR => 0 );
=cut
=cut
@ISA = qw(Exporter);
@ISA = qw(Exporter);
-@EXPORT = qw();
+@EXPORT = qw(git_cmd_try);
# Methods which can be called as standalone functions as well:
# Methods which can be called as standalone functions as well:
-@EXPORT_OK = qw(command command_oneline command_pipe command_noisy
- exec_path hash_object);
+@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
=head1 DESCRIPTION
called as methods of the object are then executed in the context of the
repository.
called as methods of the object are then executed in the context of the
repository.
-TODO: In the future, we might also do
+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.)
- my $subdir = $repo->subdir('Documentation');
- # Gets called in the subdirectory context:
- $subdir->command('status');
+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();
my $remoterepo = $repo->remote_repository (Name => 'cogito', Branch => 'master');
$remoterepo ||= Git->remote_repository ('http://git.or.cz/cogito.git/');
my @refs = $remoterepo->refs();
-So far, all functions just die if anything goes wrong. If you don't want that,
-make appropriate provisions to catch the possible deaths. Better error recovery
-mechanisms will be provided in the future.
-
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
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
=cut
=cut
-use Carp qw(carp croak);
+use Carp qw(carp croak); # but croak is bad - throw instead
+use Error qw(:try);
+use Cwd qw(abs_path);
require XSLoader;
XSLoader::load('Git', $VERSION);
require XSLoader;
XSLoader::load('Git', $VERSION);
B<WorkingCopy> - Path to the associated working copy; not strictly required
as many commands will happily crunch on a bare repository.
B<WorkingCopy> - Path to the associated working copy; not strictly required
as many commands will happily crunch on a bare repository.
-B<Directory> - Path to the Git working directory in its usual setup. This
-is just for convenient setting of both C<Repository> and C<WorkingCopy>
-at once: If the directory as a C<.git> subdirectory, C<Repository> is pointed
-to the subdirectory and the directory is assumed to be the working copy.
-If the directory does not have the subdirectory, C<WorkingCopy> is left
-undefined and C<Repository> is pointed to the directory itself.
+B<WorkingSubdir> - Subdirectory in the working copy to work inside.
+Just left undefined if you do not want to limit the scope of operations.
+
+B<Directory> - Path to the Git working directory in its usual setup.
+The C<.git> directory is searched in the directory and all the parent
+directories; if found, C<WorkingCopy> is set to the directory containing
+it and C<Repository> to the C<.git> directory itself. If no C<.git>
+directory was found, the C<Directory> is assumed to be a bare repository,
+C<Repository> is set to point at it and C<WorkingCopy> is left undefined.
+If the C<$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.
You should not use both C<Directory> and either of C<Repository> and
C<WorkingCopy> - the results of that are undefined.
field.
Calling the constructor with no options whatsoever is equivalent to
field.
Calling the constructor with no options whatsoever is equivalent to
-calling it with C<< Directory => '.' >>.
+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
=cut
if (defined $args[0]) {
if ($#args % 2 != 1) {
# Not a hash.
if (defined $args[0]) {
if ($#args % 2 != 1) {
# Not a hash.
- $#args == 0 or croak "bad usage";
- %opts = (Directory => $args[0]);
+ $#args == 0 or throw Error::Simple("bad usage");
+ %opts = ( Directory => $args[0] );
} else {
%opts = @args;
}
} else {
%opts = @args;
}
+ }
- if ($opts{Directory}) {
- -d $opts{Directory} or croak "Directory not found: $!";
- if (-d $opts{Directory}."/.git") {
- # TODO: Might make this more clever
- $opts{WorkingCopy} = $opts{Directory};
- $opts{Repository} = $opts{Directory}."/.git";
- } else {
- $opts{Repository} = $opts{Directory};
+ 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) {
+ $opts{Repository} = abs_path($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)) = '';
}
}
- delete $opts{Directory};
+ $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 };
}
$self = { opts => \%opts };
=item command ( COMMAND [, ARGUMENTS... ] )
=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>.
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).
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).
=cut
sub command {
=cut
sub command {
- my $fh = command_pipe(@_);
+ my ($fh, $ctx) = command_output_pipe(@_);
if (not defined wantarray) {
if (not defined wantarray) {
- _cmd_close($fh);
+ # Nothing to pepper the possible exception with.
+ _cmd_close($fh, $ctx);
} elsif (not wantarray) {
local $/;
my $text = <$fh>;
} elsif (not wantarray) {
local $/;
my $text = <$fh>;
- _cmd_close($fh);
+ try {
+ _cmd_close($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>;
return $text;
} else {
my @lines = <$fh>;
- _cmd_close($fh);
chomp @lines;
chomp @lines;
+ try {
+ _cmd_close($fh, $ctx);
+ } catch Git::Error::Command with {
+ my $E = shift;
+ $E->{'-outputref'} = \@lines;
+ throw $E;
+ };
return @lines;
}
}
return @lines;
}
}
=item command_oneline ( COMMAND [, ARGUMENTS... ] )
=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.
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 {
=cut
sub command_oneline {
- my $fh = command_pipe(@_);
+ my ($fh, $ctx) = command_output_pipe(@_);
my $line = <$fh>;
my $line = <$fh>;
- _cmd_close($fh);
-
- chomp $line;
+ 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;
}
return $line;
}
-=item command_pipe ( COMMAND [, ARGUMENTS... ] )
+=item command_output_pipe ( COMMAND [, ARGUMENTS... ] )
+
+=item command_output_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
Execute the given C<COMMAND> in the same way as command()
does but return a pipe filehandle from which the command output can be
read.
Execute the given C<COMMAND> in the same way as command()
does but return a pipe filehandle from which the command output can be
read.
+The function can return C<($pipe, $ctx)> in array context.
+See C<command_close_pipe()> for details.
+
=cut
=cut
-sub command_pipe {
- my ($self, $cmd, @args) = _maybe_self(@_);
+sub command_output_pipe {
+ _command_common_pipe('-|', @_);
+}
- $cmd =~ /^[a-z0-9A-Z_-]+$/ or croak "bad command: $cmd";
- my $pid = open(my $fh, "-|");
- if (not defined $pid) {
- croak "open failed: $!";
- } elsif ($pid == 0) {
- _cmd_exec($self, $cmd, @args);
- }
- return $fh;
+=item command_input_pipe ( COMMAND [, ARGUMENTS... ] )
+
+=item command_input_pipe ( [ COMMAND, ARGUMENTS... ], { Opt => Val ... } )
+
+Execute the given C<COMMAND> in the same way as command_output_pipe()
+does but return an input pipe filehandle instead; the command output
+is not captured.
+
+The function can return C<($pipe, $ctx)> in array context.
+See C<command_close_pipe()> for details.
+
+=cut
+
+sub command_input_pipe {
+ _command_common_pipe('|-', @_);
+}
+
+
+=item command_close_pipe ( PIPE [, CTX ] )
+
+Close the C<PIPE> as returned from C<command_*_pipe()>, checking
+whether the command finished successfuly. The optional C<CTX> argument
+is required if you want to see the command name in the error message,
+and it is the second value returned by C<command_*_pipe()> when
+called in array context. The call idiom is:
+
+ my ($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, $ctx);
}
}
sub command_noisy {
my ($self, $cmd, @args) = _maybe_self(@_);
sub command_noisy {
my ($self, $cmd, @args) = _maybe_self(@_);
-
- $cmd =~ /^[a-z0-9A-Z_-]+$/ or croak "bad command: $cmd";
+ _check_valid_cmd($cmd);
my $pid = fork;
if (not defined $pid) {
my $pid = fork;
if (not defined $pid) {
- croak "fork failed: $!";
+ throw Error::Simple("fork failed: $!");
} elsif ($pid == 0) {
_cmd_exec($self, $cmd, @args);
}
} elsif ($pid == 0) {
_cmd_exec($self, $cmd, @args);
}
- if (waitpid($pid, 0) > 0 and $? != 0) {
- croak "exit status: $?";
+ if (waitpid($pid, 0) > 0 and $?>>8 != 0) {
+ throw Git::Error::Command(join(' ', $cmd, @args), $? >> 8);
}
}
}
}
+=item version ()
+
+Return the Git version in use.
+
+Implementation of this function is very fast; no external command calls
+are involved.
+
+=cut
+
+# Implemented in Git.xs.
+
+
=item exec_path ()
=item exec_path ()
-Return path to the git sub-command executables (the same as
+Return path to the Git sub-command executables (the same as
C<git --exec-path>). Useful mostly only internally.
Implementation of this function is very fast; no external command calls
C<git --exec-path>). Useful mostly only internally.
Implementation of this function is very fast; no external command calls
# Implemented in Git.xs.
# Implemented in Git.xs.
+=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 hash_object ( FILENAME [, TYPE ] )
=item hash_object ( FILEHANDLE [, TYPE ] )
=item hash_object ( FILENAME [, TYPE ] )
=item hash_object ( FILEHANDLE [, TYPE ] )
# Implemented in Git.xs.
# Implemented in Git.xs.
+
=back
=back
-=head1 TODO
+=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];
+}
+
-This is still fairly crude.
-We need some good way to report errors back except just dying.
+=back
=head1 COPYRIGHT
=head1 COPYRIGHT
ref $_[0] eq 'Git' ? @_ : (undef, @_);
}
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 $pid = open(my $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 ($self) {
# When already in the subprocess, set up the appropriate state
# for the given repository and execute the git command.
sub _cmd_exec {
my ($self, @args) = @_;
if ($self) {
- $self->{opts}->{Repository} and $ENV{'GIT_DIR'} = $self->{opts}->{Repository};
- $self->{opts}->{WorkingCopy} and chdir($self->{opts}->{WorkingCopy});
+ $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());
}
}
- xs__execv_git_cmd(@args);
- croak "exec failed: $!";
+ _execv_git_cmd(@args);
+ die "exec failed: $!";
}
# Execute the given Git command ($_[0]) with arguments ($_[1..])
}
# Execute the given Git command ($_[0]) with arguments ($_[1..])
# Close pipe to a subprocess.
sub _cmd_close {
# Close pipe to a subprocess.
sub _cmd_close {
- my ($fh) = @_;
+ my ($fh, $ctx) = @_;
if (not close $fh) {
if ($!) {
# It's just close, no point in fatalities
carp "error closing pipe: $!";
} elsif ($? >> 8) {
if (not close $fh) {
if ($!) {
# It's just close, no point in fatalities
carp "error closing pipe: $!";
} elsif ($? >> 8) {
- croak "exit status: ".($? >> 8);
+ # The caller should pepper this.
+ throw Git::Error::Command($ctx, $? >> 8);
}
# else we might e.g. closed a live stream; the command
# dying of SIGPIPE would drive us here.
}
# else we might e.g. closed a live stream; the command
# dying of SIGPIPE would drive us here.
#xs_call_gate($self->{opts}->{Repository});
}
#xs_call_gate($self->{opts}->{Repository});
}
+ # Having to call throw from the C code is a sure path to insanity.
+ local $SIG{__DIE__} = sub { throw Error::Simple("@_"); };
&$xsfunc(@args);
}
&$xsfunc(@args);
}
my $xsname;
our $AUTOLOAD;
($xsname = $AUTOLOAD) =~ s/.*:://;
my $xsname;
our $AUTOLOAD;
($xsname = $AUTOLOAD) =~ s/.*:://;
- croak "&Git::$xsname not defined" if $xsname =~ /^xs_/;
+ throw Error::Simple("&Git::$xsname not defined") if $xsname =~ /^xs_/;
$xsname = 'xs_'.$xsname;
_call_gate(\&$xsname, @_);
}
$xsname = 'xs_'.$xsname;
_call_gate(\&$xsname, @_);
}