Bug #54955 for Parse-DMIDecode: [PATCH] Better handling of failures when invoking dmidecode

This patch better handles the cases where dmidecode exits in error. Common cases for the error exit are: - you are not root - you are root, but cannot read /dev/mem (common on paravirtualized Linux systems) Without this patch, failures give you error output like: /dev/mem: Permission denied Unable to close file handle for command '/usr/sbin/dmidecode': at -e line 1 and with it: Command '/usr/sbin/dmidecode' exited with exit code 1 at -e line 1 which is a bit more palatable (and doesn't spew to the caller's stdout). diff --git a/lib/Parse/DMIDecode.pm b/lib/Parse/DMIDecode.pm index 6258031..441bff1 100644 --- a/lib/Parse/DMIDecode.pm +++ b/lib/Parse/DMIDecode.pm @@ -89,11 +89,48 @@ sub probe { my $fh; local %ENV = %ENV; delete @ENV{qw(IFS CDPATH ENV BASH_ENV PATH)}; - open($fh,'-|',$cmd) || croak "Unable to open file handle for command '$cmd': $!"; - while (local $_ = <$fh>) { - $stor->{raw} .= $_; + + my $pid = open($fh, '-|'); + + if( ! defined $pid ) { + die("Could not fork: $!"); + } + + if( $pid == 0 ) { + # in child + + # Throw away stderr + open(STDERR, '>/dev/null'); + + # new scope to silence Perl warning about code after an + # exec... see 'perldoc exec' for details + { + # Also suppress warnings about exec problems; we'll get + # them below from $! if they actually matter (like + # file not found, etc) + no warnings 'exec'; + exec $cmd; + } + die qq{Could not exec $cmd: $!}; } - close($fh) || carp "Unable to close file handle for command '$cmd': $!"; + + if( ! $fh ) { + croak "No filehandle opened for command '$cmd'"; + } + + # Slurp in entire output + $stor->{raw} = do { local $/; <$fh> }; + + my $rc = close($fh); + + if( ! $rc ) { + my $exitcode = $? >> 8; + my $signal = $? & 127; + carp "Error closing pipe from command '$cmd': $!" if $!; + carp "Command '$cmd' exited due to signal $signal" if ($signal != 0); + carp "Command '$cmd' exited with exit code $exitcode" if ($exitcode != 0); + } + return $self->parse($stor->{raw}); } -- Dave O'Neill <dmo@roaringpenguin.com> Roaring Penguin Software Inc. +1 (613) 231-6599 http://www.roaringpenguin.com/ For CanIt technical support, please mail: support@roaringpenguin.com