Net-SNMP-XS/XS.pm

=head1 NAME

Net::SNMP::XS - speed up Net::SNMP by decoding in XS, with limitations

=head1 SYNOPSIS

 use Net::SNMP::XS;

 # loading it is enough, there are no public symbols

=head1 DESCRIPTION

This module tries to speed up Net::SNMP response packet decoding.

It does this by overriding a few selected internal method by (almost)
equivalent XS methods.

This currently reduces decode time by a factor of ten for typical bulk
responses.

There are currently the following limitations when using this module:

=over 4

=item overriding internal functions might cause the module to
malfunction with future versions of Net::SNMP

=item error messages will be simpler/different

=item translation will be ignored (all values will be delivered "raw")

=item a moderately modern (>= C99) C compiler is required

=item only tested with 5.10, no intentions to port to older perls

=item duplicate OIDs are not supported

=item REPORT PDUs are not supported

=back

=cut

package Net::SNMP::XS;

use strict qw(vars subs);
no warnings;

use Guard;

use Net::SNMP ();
use Net::SNMP::PDU ();
use Net::SNMP::Message ();
use Net::SNMP::MessageProcessing ();

our $VERSION;
our $old_prepare;

BEGIN {
   $VERSION = '0.03';

   $old_prepare = \&Net::SNMP::MessageProcessing::prepare_data_elements;

   # this overrides many methods inside
   require XSLoader;
   XSLoader::load Net::SNMP::XS, $VERSION;
}

sub Net::SNMP::MessageProcessing::prepare_data_elements {
   my ($self, $msg) = @_;

   set_msg $msg, $msg->{_buffer};
   scope_guard \&clr_msg;
   &$old_prepare
}

package Net::SNMP::Message;

Net::SNMP::XS::set_type INTEGER          , \&_process_integer32;
Net::SNMP::XS::set_type OCTET_STRING     , \&_process_octet_string;
Net::SNMP::XS::set_type NULL             , \&_process_null;
Net::SNMP::XS::set_type OBJECT_IDENTIFIER, \&_process_object_identifier;
Net::SNMP::XS::set_type SEQUENCE         , \&_process_sequence;
Net::SNMP::XS::set_type IPADDRESS        , \&_process_ipaddress;
Net::SNMP::XS::set_type COUNTER          , \&_process_counter;
Net::SNMP::XS::set_type GAUGE            , \&_process_gauge;
Net::SNMP::XS::set_type TIMETICKS        , \&_process_timeticks;
Net::SNMP::XS::set_type OPAQUE           , \&_process_opaque;
Net::SNMP::XS::set_type COUNTER64        , \&_process_counter64;
Net::SNMP::XS::set_type NOSUCHOBJECT     , \&_process_nosuchobject;
Net::SNMP::XS::set_type NOSUCHINSTANCE   , \&_process_nosuchinstance;
Net::SNMP::XS::set_type ENDOFMIBVIEW     , \&_process_endofmibview;
Net::SNMP::XS::set_type GET_REQUEST      , \&_process_get_request;
Net::SNMP::XS::set_type GET_NEXT_REQUEST , \&_process_get_next_request;
Net::SNMP::XS::set_type GET_RESPONSE     , \&_process_get_response;
Net::SNMP::XS::set_type SET_REQUEST      , \&_process_set_request;
Net::SNMP::XS::set_type TRAP             , \&_process_trap;
Net::SNMP::XS::set_type GET_BULK_REQUEST , \&_process_get_bulk_request;
Net::SNMP::XS::set_type INFORM_REQUEST   , \&_process_inform_request;
Net::SNMP::XS::set_type SNMPV2_TRAP      , \&_process_v2_trap;
Net::SNMP::XS::set_type REPORT           , \&_process_report;

package Net::SNMP::PDU;

# var_bind_list hardcodes oid_lext_sort. *sigh*
# we copy it 1:1, except for using oid_lex_sort.

sub var_bind_list
{
   my ($this, $vbl, $types) = @_;

   return if defined($this->{_error});

   if (@_ > 1) {
      # The VarBindList HASH is being updated from an external
      # source.  We need to update the VarBind names ARRAY to
      # correspond to the new keys of the HASH.  If the updated
      # information is valid, we will use lexicographical ordering
      # for the ARRAY entries since we do not have a PDU to use
      # to determine the ordering.  The ASN.1 types HASH is also
      # updated here if a cooresponding HASH is passed.  We double
      # check the mapping by populating the hash with the keys of
      # the VarBindList HASH. 

      if (!defined($vbl) || (ref($vbl) ne 'HASH')) {

         $this->{_var_bind_list}  = undef;
         $this->{_var_bind_names} = [];
         $this->{_var_bind_types} = undef; 

      } else {

         $this->{_var_bind_list} = $vbl;

         @{$this->{_var_bind_names}} = Net::SNMP::oid_lex_sort keys %$vbl;

         if (!defined($types) || (ref($types) ne 'HASH')) {
             $types = {};
         }

         map { 
            $this->{_var_bind_types}->{$_} = 
               exists($types->{$_}) ? $types->{$_} : undef; 
         } keys(%{$vbl});

      }

   }

   $this->{_var_bind_list};
}

1;

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

Revision:	1.9
Committed:	Sun Apr 12 00:48:39 2009 UTC (15 years, 2 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_03
Changes since 1.8:	+1 -3 lines
Log Message:	0.03
#	Content
1	=head1 NAME
2
3	Net::SNMP::XS - speed up Net::SNMP by decoding in XS, with limitations
4
5	=head1 SYNOPSIS
6
7	use Net::SNMP::XS;
8
9	# loading it is enough, there are no public symbols
10
11	=head1 DESCRIPTION
12
13	This module tries to speed up Net::SNMP response packet decoding.
14
15	It does this by overriding a few selected internal method by (almost)
16	equivalent XS methods.
17
18	This currently reduces decode time by a factor of ten for typical bulk
19	responses.
20
21	There are currently the following limitations when using this module:
22
23	=over 4
24
25	=item overriding internal functions might cause the module to
26	malfunction with future versions of Net::SNMP
27
28	=item error messages will be simpler/different
29
30	=item translation will be ignored (all values will be delivered "raw")
31
32	=item a moderately modern (>= C99) C compiler is required
33
34	=item only tested with 5.10, no intentions to port to older perls
35
36	=item duplicate OIDs are not supported
37
38	=item REPORT PDUs are not supported
39
40	=back
41
42	=cut
43
44	package Net::SNMP::XS;
45
46	use strict qw(vars subs);
47	no warnings;
48
49	use Guard;
50
51	use Net::SNMP ();
52	use Net::SNMP::PDU ();
53	use Net::SNMP::Message ();
54	use Net::SNMP::MessageProcessing ();
55
56	our $VERSION;
57	our $old_prepare;
58
59	BEGIN {
60	$VERSION = '0.03';
61
62	$old_prepare = \&Net::SNMP::MessageProcessing::prepare_data_elements;
63
64	# this overrides many methods inside
65	require XSLoader;
66	XSLoader::load Net::SNMP::XS, $VERSION;
67	}
68
69	sub Net::SNMP::MessageProcessing::prepare_data_elements {
70	my ($self, $msg) = @_;
71
72	set_msg $msg, $msg->{_buffer};
73	scope_guard \&clr_msg;
74	&$old_prepare
75	}
76
77	package Net::SNMP::Message;
78
79	Net::SNMP::XS::set_type INTEGER , \&_process_integer32;
80	Net::SNMP::XS::set_type OCTET_STRING , \&_process_octet_string;
81	Net::SNMP::XS::set_type NULL , \&_process_null;
82	Net::SNMP::XS::set_type OBJECT_IDENTIFIER, \&_process_object_identifier;
83	Net::SNMP::XS::set_type SEQUENCE , \&_process_sequence;
84	Net::SNMP::XS::set_type IPADDRESS , \&_process_ipaddress;
85	Net::SNMP::XS::set_type COUNTER , \&_process_counter;
86	Net::SNMP::XS::set_type GAUGE , \&_process_gauge;
87	Net::SNMP::XS::set_type TIMETICKS , \&_process_timeticks;
88	Net::SNMP::XS::set_type OPAQUE , \&_process_opaque;
89	Net::SNMP::XS::set_type COUNTER64 , \&_process_counter64;
90	Net::SNMP::XS::set_type NOSUCHOBJECT , \&_process_nosuchobject;
91	Net::SNMP::XS::set_type NOSUCHINSTANCE , \&_process_nosuchinstance;
92	Net::SNMP::XS::set_type ENDOFMIBVIEW , \&_process_endofmibview;
93	Net::SNMP::XS::set_type GET_REQUEST , \&_process_get_request;
94	Net::SNMP::XS::set_type GET_NEXT_REQUEST , \&_process_get_next_request;
95	Net::SNMP::XS::set_type GET_RESPONSE , \&_process_get_response;
96	Net::SNMP::XS::set_type SET_REQUEST , \&_process_set_request;
97	Net::SNMP::XS::set_type TRAP , \&_process_trap;
98	Net::SNMP::XS::set_type GET_BULK_REQUEST , \&_process_get_bulk_request;
99	Net::SNMP::XS::set_type INFORM_REQUEST , \&_process_inform_request;
100	Net::SNMP::XS::set_type SNMPV2_TRAP , \&_process_v2_trap;
101	Net::SNMP::XS::set_type REPORT , \&_process_report;
102
103	package Net::SNMP::PDU;
104
105	# var_bind_list hardcodes oid_lext_sort. sigh
106	# we copy it 1:1, except for using oid_lex_sort.
107
108	sub var_bind_list
109	{
110	my ($this, $vbl, $types) = @_;
111
112	return if defined($this->{_error});
113
114	if (@_ > 1) {
115	# The VarBindList HASH is being updated from an external
116	# source. We need to update the VarBind names ARRAY to
117	# correspond to the new keys of the HASH. If the updated
118	# information is valid, we will use lexicographical ordering
119	# for the ARRAY entries since we do not have a PDU to use
120	# to determine the ordering. The ASN.1 types HASH is also
121	# updated here if a cooresponding HASH is passed. We double
122	# check the mapping by populating the hash with the keys of
123	# the VarBindList HASH.
124
125	if (!defined($vbl) \|\| (ref($vbl) ne 'HASH')) {
126
127	$this->{_var_bind_list} = undef;
128	$this->{_var_bind_names} = [];
129	$this->{_var_bind_types} = undef;
130
131	} else {
132
133	$this->{_var_bind_list} = $vbl;
134
135	@{$this->{_var_bind_names}} = Net::SNMP::oid_lex_sort keys %$vbl;
136
137	if (!defined($types) \|\| (ref($types) ne 'HASH')) {
138	$types = {};
139	}
140
141	map {
142	$this->{_var_bind_types}->{$_} =
143	exists($types->{$_}) ? $types->{$_} : undef;
144	} keys(%{$vbl});
145
146	}
147
148	}
149
150	$this->{_var_bind_list};
151	}
152
153	1;
154
155	=head1 AUTHOR
156
157	Marc Lehmann <schmorp@schmorp.de>
158	http://home.schmorp.de/
159
160	=cut
161