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Diffstat (limited to 'contrib/perl5/lib/IPC/Open3.pm')
| -rw-r--r-- | contrib/perl5/lib/IPC/Open3.pm | 333 |
1 files changed, 0 insertions, 333 deletions
diff --git a/contrib/perl5/lib/IPC/Open3.pm b/contrib/perl5/lib/IPC/Open3.pm deleted file mode 100644 index 5c9c69a..0000000 --- a/contrib/perl5/lib/IPC/Open3.pm +++ /dev/null @@ -1,333 +0,0 @@ -package IPC::Open3; - -use strict; -no strict 'refs'; # because users pass me bareword filehandles -our ($VERSION, @ISA, @EXPORT); - -require Exporter; - -use Carp; -use Symbol qw(gensym qualify); - -$VERSION = 1.0103; -@ISA = qw(Exporter); -@EXPORT = qw(open3); - -=head1 NAME - -IPC::Open3, open3 - open a process for reading, writing, and error handling - -=head1 SYNOPSIS - - $pid = open3(\*WTRFH, \*RDRFH, \*ERRFH, - 'some cmd and args', 'optarg', ...); - - my($wtr, $rdr, $err); - $pid = open3($wtr, $rdr, $err, - 'some cmd and args', 'optarg', ...); - -=head1 DESCRIPTION - -Extremely similar to open2(), open3() spawns the given $cmd and -connects RDRFH for reading, WTRFH for writing, and ERRFH for errors. If -ERRFH is false, or the same file descriptor as RDRFH, then STDOUT and -STDERR of the child are on the same filehandle. The WTRFH will have -autoflush turned on. - -If WTRFH begins with C<< <& >>, then WTRFH will be closed in the parent, and -the child will read from it directly. If RDRFH or ERRFH begins with -C<< >& >>, then the child will send output directly to that filehandle. -In both cases, there will be a dup(2) instead of a pipe(2) made. - -If either reader or writer is the null string, this will be replaced -by an autogenerated filehandle. If so, you must pass a valid lvalue -in the parameter slot so it can be overwritten in the caller, or -an exception will be raised. - -The filehandles may also be integers, in which case they are understood -as file descriptors. - -open3() returns the process ID of the child process. It doesn't return on -failure: it just raises an exception matching C</^open3:/>. However, -C<exec> failures in the child are not detected. You'll have to -trap SIGPIPE yourself. - -open3() does not wait for and reap the child process after it exits. -Except for short programs where it's acceptable to let the operating system -take care of this, you need to do this yourself. This is normally as -simple as calling C<waitpid $pid, 0> when you're done with the process. -Failing to do this can result in an accumulation of defunct or "zombie" -processes. See L<perlfunc/waitpid> for more information. - -If you try to read from the child's stdout writer and their stderr -writer, you'll have problems with blocking, which means you'll want -to use select() or the IO::Select, which means you'd best use -sysread() instead of readline() for normal stuff. - -This is very dangerous, as you may block forever. It assumes it's -going to talk to something like B<bc>, both writing to it and reading -from it. This is presumably safe because you "know" that commands -like B<bc> will read a line at a time and output a line at a time. -Programs like B<sort> that read their entire input stream first, -however, are quite apt to cause deadlock. - -The big problem with this approach is that if you don't have control -over source code being run in the child process, you can't control -what it does with pipe buffering. Thus you can't just open a pipe to -C<cat -v> and continually read and write a line from it. - -=head1 WARNING - -The order of arguments differs from that of open2(). - -=cut - -# &open3: Marc Horowitz <marc@mit.edu> -# derived mostly from &open2 by tom christiansen, <tchrist@convex.com> -# fixed for 5.001 by Ulrich Kunitz <kunitz@mai-koeln.com> -# ported to Win32 by Ron Schmidt, Merrill Lynch almost ended my career -# fixed for autovivving FHs, tchrist again -# allow fd numbers to be used, by Frank Tobin -# -# $Id: open3.pl,v 1.1 1993/11/23 06:26:15 marc Exp $ -# -# usage: $pid = open3('wtr', 'rdr', 'err' 'some cmd and args', 'optarg', ...); -# -# spawn the given $cmd and connect rdr for -# reading, wtr for writing, and err for errors. -# if err is '', or the same as rdr, then stdout and -# stderr of the child are on the same fh. returns pid -# of child (or dies on failure). - - -# if wtr begins with '<&', then wtr will be closed in the parent, and -# the child will read from it directly. if rdr or err begins with -# '>&', then the child will send output directly to that fd. In both -# cases, there will be a dup() instead of a pipe() made. - - -# WARNING: this is dangerous, as you may block forever -# unless you are very careful. -# -# $wtr is left unbuffered. -# -# abort program if -# rdr or wtr are null -# a system call fails - -our $Me = 'open3 (bug)'; # you should never see this, it's always localized - -# Fatal.pm needs to be fixed WRT prototypes. - -sub xfork { - my $pid = fork; - defined $pid or croak "$Me: fork failed: $!"; - return $pid; -} - -sub xpipe { - pipe $_[0], $_[1] or croak "$Me: pipe($_[0], $_[1]) failed: $!"; -} - -# I tried using a * prototype character for the filehandle but it still -# disallows a bearword while compiling under strict subs. - -sub xopen { - open $_[0], $_[1] or croak "$Me: open($_[0], $_[1]) failed: $!"; -} - -sub xclose { - close $_[0] or croak "$Me: close($_[0]) failed: $!"; -} - -sub fh_is_fd { - return $_[0] =~ /\A=?(\d+)\z/; -} - -sub xfileno { - return $1 if $_[0] =~ /\A=?(\d+)\z/; # deal with fh just being an fd - return fileno $_[0]; -} - -my $do_spawn = $^O eq 'os2' || $^O eq 'MSWin32'; - -sub _open3 { - local $Me = shift; - my($package, $dad_wtr, $dad_rdr, $dad_err, @cmd) = @_; - my($dup_wtr, $dup_rdr, $dup_err, $kidpid); - - # simulate autovivification of filehandles because - # it's too ugly to use @_ throughout to make perl do it for us - # tchrist 5-Mar-00 - - unless (eval { - $dad_wtr = $_[1] = gensym unless defined $dad_wtr && length $dad_wtr; - $dad_rdr = $_[2] = gensym unless defined $dad_rdr && length $dad_rdr; - 1; }) - { - # must strip crud for croak to add back, or looks ugly - $@ =~ s/(?<=value attempted) at .*//s; - croak "$Me: $@"; - } - - $dad_err ||= $dad_rdr; - - $dup_wtr = ($dad_wtr =~ s/^[<>]&//); - $dup_rdr = ($dad_rdr =~ s/^[<>]&//); - $dup_err = ($dad_err =~ s/^[<>]&//); - - # force unqualified filehandles into caller's package - $dad_wtr = qualify $dad_wtr, $package unless fh_is_fd($dad_wtr); - $dad_rdr = qualify $dad_rdr, $package unless fh_is_fd($dad_rdr); - $dad_err = qualify $dad_err, $package unless fh_is_fd($dad_err); - - my $kid_rdr = gensym; - my $kid_wtr = gensym; - my $kid_err = gensym; - - xpipe $kid_rdr, $dad_wtr if !$dup_wtr; - xpipe $dad_rdr, $kid_wtr if !$dup_rdr; - xpipe $dad_err, $kid_err if !$dup_err && $dad_err ne $dad_rdr; - - $kidpid = $do_spawn ? -1 : xfork; - if ($kidpid == 0) { # Kid - # If she wants to dup the kid's stderr onto her stdout I need to - # save a copy of her stdout before I put something else there. - if ($dad_rdr ne $dad_err && $dup_err - && xfileno($dad_err) == fileno(STDOUT)) { - my $tmp = gensym; - xopen($tmp, ">&$dad_err"); - $dad_err = $tmp; - } - - if ($dup_wtr) { - xopen \*STDIN, "<&$dad_wtr" if fileno(STDIN) != xfileno($dad_wtr); - } else { - xclose $dad_wtr; - xopen \*STDIN, "<&=" . fileno $kid_rdr; - } - if ($dup_rdr) { - xopen \*STDOUT, ">&$dad_rdr" if fileno(STDOUT) != xfileno($dad_rdr); - } else { - xclose $dad_rdr; - xopen \*STDOUT, ">&=" . fileno $kid_wtr; - } - if ($dad_rdr ne $dad_err) { - if ($dup_err) { - # I have to use a fileno here because in this one case - # I'm doing a dup but the filehandle might be a reference - # (from the special case above). - xopen \*STDERR, ">&" . xfileno($dad_err) - if fileno(STDERR) != xfileno($dad_err); - } else { - xclose $dad_err; - xopen \*STDERR, ">&=" . fileno $kid_err; - } - } else { - xopen \*STDERR, ">&STDOUT" if fileno(STDERR) != fileno(STDOUT); - } - local($")=(" "); - exec @cmd # XXX: wrong process to croak from - or croak "$Me: exec of @cmd failed"; - } elsif ($do_spawn) { - # All the bookkeeping of coincidence between handles is - # handled in spawn_with_handles. - - my @close; - if ($dup_wtr) { - $kid_rdr = \*{$dad_wtr}; - push @close, $kid_rdr; - } else { - push @close, \*{$dad_wtr}, $kid_rdr; - } - if ($dup_rdr) { - $kid_wtr = \*{$dad_rdr}; - push @close, $kid_wtr; - } else { - push @close, \*{$dad_rdr}, $kid_wtr; - } - if ($dad_rdr ne $dad_err) { - if ($dup_err) { - $kid_err = \*{$dad_err}; - push @close, $kid_err; - } else { - push @close, \*{$dad_err}, $kid_err; - } - } else { - $kid_err = $kid_wtr; - } - require IO::Pipe; - $kidpid = eval { - spawn_with_handles( [ { mode => 'r', - open_as => $kid_rdr, - handle => \*STDIN }, - { mode => 'w', - open_as => $kid_wtr, - handle => \*STDOUT }, - { mode => 'w', - open_as => $kid_err, - handle => \*STDERR }, - ], \@close, @cmd); - }; - die "$Me: $@" if $@; - } - - xclose $kid_rdr if !$dup_wtr; - xclose $kid_wtr if !$dup_rdr; - xclose $kid_err if !$dup_err && $dad_rdr ne $dad_err; - # If the write handle is a dup give it away entirely, close my copy - # of it. - xclose $dad_wtr if $dup_wtr; - - select((select($dad_wtr), $| = 1)[0]); # unbuffer pipe - $kidpid; -} - -sub open3 { - if (@_ < 4) { - local $" = ', '; - croak "open3(@_): not enough arguments"; - } - return _open3 'open3', scalar caller, @_ -} - -sub spawn_with_handles { - my $fds = shift; # Fields: handle, mode, open_as - my $close_in_child = shift; - my ($fd, $pid, @saved_fh, $saved, %saved, @errs); - require Fcntl; - - foreach $fd (@$fds) { - $fd->{tmp_copy} = IO::Handle->new_from_fd($fd->{handle}, $fd->{mode}); - $saved{fileno $fd->{handle}} = $fd->{tmp_copy}; - } - foreach $fd (@$fds) { - bless $fd->{handle}, 'IO::Handle' - unless eval { $fd->{handle}->isa('IO::Handle') } ; - # If some of handles to redirect-to coincide with handles to - # redirect, we need to use saved variants: - $fd->{handle}->fdopen($saved{fileno $fd->{open_as}} || $fd->{open_as}, - $fd->{mode}); - } - unless ($^O eq 'MSWin32') { - # Stderr may be redirected below, so we save the err text: - foreach $fd (@$close_in_child) { - fcntl($fd, Fcntl::F_SETFD(), 1) or push @errs, "fcntl $fd: $!" - unless $saved{fileno $fd}; # Do not close what we redirect! - } - } - - unless (@errs) { - $pid = eval { system 1, @_ }; # 1 == P_NOWAIT - push @errs, "IO::Pipe: Can't spawn-NOWAIT: $!" if !$pid || $pid < 0; - } - - foreach $fd (@$fds) { - $fd->{handle}->fdopen($fd->{tmp_copy}, $fd->{mode}); - $fd->{tmp_copy}->close or croak "Can't close: $!"; - } - croak join "\n", @errs if @errs; - return $pid; -} - -1; # so require is happy |
