freeswitch/libs/libtpl-1.5/lang/perl/Tpl.pm
2012-09-13 15:01:01 -05:00

476 lines
19 KiB
Perl
Executable File

package Tpl;
# Copyright (c) 2005-2007, Troy Hanson http://tpl.sourceforge.net
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
# * Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived
# from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
# IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
# OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
use strict;
use warnings;
use Config; # to get the size of "double" on this platform
use bytes; # always use byte (not unicode char) offsets w/tpl images
our $VERSION = 1.1;
# tpl object is a reference to a hash with these keys:
#
# A(0):
# ... :
# A(n):
#
# where each A(i) refers to an A node, except A(0) is the root node.
#
# For each hash key (A node or root node), the value of that key is
# a list reference. The members are of the list are the node's children.
# They're represented as "Ai" (for A nodes) where i is a positive integer;
# for non-A nodes the representation is [type,addr] e.g. [ "i", \$some_integer]
#
# For example,
# Tpl->map("iA(ib)", \$x, \$y, \$z);
# returns a tpl object which is a reference to a hash with these keys/values:
#
# $self->{A0} = [ [ "i", \$x ], "A1" ];
# $self->{A1} = [ [ "i", \$y ], [ "b", \$z ] ];
#
# Now if A1 (that is, the "A(ib)" node) is packed, the tpl object acquires
# another hash key/value:
# $self->{P1} = [ $binary_int, $binary_byte ];
# and repeated calls to pack A1 append further $binary elements.
#
sub tpl_map {
my $invocant = shift;
my $class = ref($invocant) || $invocant;
my $fmt = shift;
my @astack = (0); # stack of current A node's lineage in tpl tree
my $a_count=0; # running count of A's, thus an index of them
my $self = {}; # populate below
my ($lparen_level,$expect_lparen,$in_structure)=(0,0,0);
for (my $i=0; $i < length $fmt; $i++) {
my $c = substr($fmt,$i,1);
if ($c eq 'A') {
$a_count++;
push @{ $self->{"A" . $astack[-1]} }, "A$a_count";
push @astack, $a_count;
$expect_lparen=1;
} elsif ($c eq '(') {
die "invalid format $fmt" unless $expect_lparen;
$expect_lparen=0;
$lparen_level++;
} elsif ($c eq ')') {
$lparen_level--;
die "invalid format $fmt" if $lparen_level < 0;
die "invalid format $fmt" if substr($fmt,$i-1,1) eq '(';
if ($in_structure && ($in_structure-1 == $lparen_level)) {
$in_structure=0;
} else {
pop @astack; # rparen ends A() type, not S() type
}
} elsif ($c eq 'S') {
# in perl we just parse and ignore the S() construct
$expect_lparen=1;
$in_structure=1+$lparen_level; # so we can tell where S fmt ends
} elsif ($c =~ /^(i|u|B|s|c|f|I|U)$/) {
die "invalid format $fmt" if $expect_lparen;
my $r = shift;
die "no reference for $c (position $i of $fmt)" unless ref($r);
if (($c eq "f") and ($Config{doublesize} != 8)) {
die "double not 8 bytes on this platform";
}
if (($c =~ /(U|I)/) and not defined ($Config{use64bitint})) {
die "Tpl.pm: this 32-bit Perl can't pack/unpack 64-bit I/U integers\n";
}
push @{ $self->{"A" . $astack[-1]} }, [ $c , $r ];
} elsif ($c eq "#") {
# test for previous iucfIU
die "unallowed length modifer" unless $self->{"A" . $astack[-1]}->[-1]->[0] =~ /^(i|u|c|I|U|f)$/;
my $n = shift;
die "non-numeric # length modifer" unless $n =~ /^\d+$/;
push @{ $self->{"A" . $astack[-1]}->[-1] }, $n;
push @{ $self->{"#"}}, $n; # master array of octothorpe lengths
} else {
die "invalid character $c in format $fmt";
}
}
die "invalid format $fmt" if $lparen_level != 0;
$self->{fmt} = $fmt;
bless $self;
return $self;
}
sub tpl_format {
my $self = shift;
return $self->{fmt};
}
sub tpl_pack {
my $self = shift;
my $i = shift;
die "invalid index" unless defined $self->{"A$i"};
die "tpl for unpacking only" if defined $self->{"loaded"};
$self->{"packed"}++;
$self->{"P$i"} = undef if $i == 0; # node 0 doesn't accumulate
my @bb;
foreach my $node (@{ $self->{"A$i"} }) {
if (ref($node)) {
my ($type,$addr,$fxlen) = @{ $node };
if (defined $fxlen) { # octothorpic array
push @bb, CORE::pack("l$fxlen",@$addr) if $type eq "i"; # int
push @bb, CORE::pack("L$fxlen",@$addr) if $type eq "u"; # uint
push @bb, CORE::pack("C$fxlen",@$addr) if $type eq "c"; # byte
push @bb, CORE::pack("d$fxlen",@$addr) if $type eq "f"; # double
push @bb, CORE::pack("q$fxlen",@$addr) if $type eq "I"; # int64
push @bb, CORE::pack("Q$fxlen",@$addr) if $type eq "U"; # uint64
} else {
# non-octothorpic singleton
push @bb, CORE::pack("l",$$addr) if $type eq "i"; # int
push @bb, CORE::pack("L",$$addr) if $type eq "u"; # uint
push @bb, CORE::pack("C",$$addr) if $type eq "c"; # byte
push @bb, CORE::pack("d",$$addr) if $type eq "f"; # double (8 byte)
push @bb, CORE::pack("q",$$addr) if $type eq "I"; # int64
push @bb, CORE::pack("Q",$$addr) if $type eq "U"; # uint64
if ($type =~ /^(B|s)$/) { # string/binary
push @bb, CORE::pack("L", length($$addr));
push @bb, CORE::pack("a*", $$addr);
}
}
} elsif ($node =~ /^A(\d+)$/) {
# encode array length (int) and the array data into one scalar
my $alen = pack("l", scalar @{ $self->{"P$1"} or [] });
my $abod = (join "", @{ $self->{"P$1"} or [] });
push @bb, $alen . $abod;
$self->{"P$1"} = undef;
} else {
die "internal error; invalid node symbol $node";
}
}
push @{ $self->{"P$i"} }, (join "", @bb);
}
sub big_endian {
return (CORE::unpack("C", CORE::pack("L",1)) == 1) ? 0 : 1;
}
sub tpl_dump {
my $self = shift;
my $filename = shift;
$self->tpl_pack(0) if not defined $self->{"P0"};
my $format = $self->tpl_format;
my $octothorpe_lens = CORE::pack("L*", @{ $self->{"#"} or [] });
my $data = (join "", @{ $self->{"P0"} });
my $ov_len = length($format) + 1 + length($octothorpe_lens) + length($data) + 8;
my $flags = big_endian() ? 1 : 0;
my $preamble = CORE::pack("CLZ*", $flags, $ov_len, $format);
my $tpl = "tpl" . $preamble . $octothorpe_lens . $data;
return $tpl unless $filename;
# here for file output
open TPL, ">$filename" or die "can't open $filename: $!";
print TPL $tpl;
close TPL;
}
sub tpl_peek {
my $invocant = shift;
my $class = ref($invocant) || $invocant;
my $tplhandle = shift;
my $tpl;
if (ref($tplhandle)) {
$tpl = $$tplhandle;
} else {
open TPL, "<$tplhandle" or die "can't open $tplhandle: $!";
undef $/; # slurp
$tpl = <TPL>;
close TPL;
}
die "invalid tpl file" unless ($tpl =~ /^tpl/);
return (unpack("Z*", substr($tpl,8)));
}
sub tpl_load {
my $self = shift;
my $tplhandle = shift;
die "tpl for packing only" if $self->{"packed"};
die "tpl reloading not supported" if $self->{"loaded"};
# read tpl image from file or was it passed directly via ref?
my $tpl;
if (ref($tplhandle)) {
$tpl = $$tplhandle;
} else {
open TPL, "<$tplhandle" or die "can't open $tplhandle: $!";
undef $/; # slurp
$tpl = <TPL>;
close TPL;
}
$self->{"TI"} = $tpl;
$self->{"TL"} = length $tpl;
# verify preamble
die "invalid image -1" unless length($tpl) >= 9;
die "invalid image -2" unless $tpl =~ /^tpl/;
my $flags = CORE::unpack("C", substr($tpl,3,1));
$self->{"xendian"} = 1 if (big_endian() != ($flags & 1));
$self->{"UF"} = ($flags & 1) ? "N" : "V";
my $ov_len = CORE::unpack($self->{"UF"}, substr($tpl,4,4));
die "invalid image -3" unless $ov_len == length($tpl);
my $format = CORE::unpack("Z*", substr($tpl,8));
die "format mismatch" unless $format eq $self->tpl_format();
my @octothorpe_lens = @{ $self->{"#"} or [] };
my $ol = 8 + length($format) + 1; # start of octothorpe lengths
for (my $i=0; $i < (scalar @octothorpe_lens); $i++) {
my $len = CORE::unpack($self->{"UF"}, substr($tpl,$ol,4));
my $olen = $octothorpe_lens[$i];
die "fixed-length array size mismatch" unless $olen == $len;
$ol += 4;
}
my $dv = $ol; # start of packed data
my $len = $self->serlen("A0",$dv);
die "invalid image -4" if $len == -1;
die "invalid image -5" if (length($tpl) != $len + $dv);
$self->{"C0"} = $dv;
$self->{"loaded"} = 1;
$self->unpackA0; # prepare root child nodes for use
}
# byte reverse a word (any length)
sub reversi {
my $word = shift;
my @w = split //, $word;
my $r = join "", (reverse @w);
return $r;
}
#
# while unpacking, the object has these keys in its hash:
# C0
# C1
# ...
# C<n>
# These are indices (into the tpl image $self->{"TI"}) from which node n
# is being unpacked. I.e. as array elements of node n are unpacked, C<n>
# advances through the tpl image.
#
# Similarly, elements
# N1
# N2
# ...
# N<n>
# refer to the remaining array count for node n.
#
sub tpl_unpack {
my $self = shift;
my $n = shift;
my $ax = "A$n";
my $cx = "C$n";
my $nx = "N$n";
my $rc;
die "tpl for packing only" if $self->{"packed"};
die "tpl not loaded" unless $self->{"loaded"};
# decrement count for non root array nodes
if ($n > 0) {
return 0 if $self->{$nx} <= 0;
$rc = $self->{$nx}--;
}
for my $c (@{ $self->{$ax} }) {
if (ref($c)) {
my ($type,$addr,$fxlen) = @$c;
if (defined $fxlen) { # octothorpic unpack
@{ $addr } = (); # empty existing list before pushing elements
for(my $i=0; $i < $fxlen; $i++) {
if ($type eq "u") { # uint
push @{ $addr }, CORE::unpack($self->{"UF"},
substr($self->{"TI"},$self->{$cx},4));
$self->{$cx} += 4;
} elsif ($type eq "i") { #int (see note below re:signed int)
my $intbytes = substr($self->{"TI"},$self->{$cx},4);
$intbytes = reversi($intbytes) if $self->{"xendian"};
push @{ $addr }, CORE::unpack("l", $intbytes);
$self->{$cx} += 4;
} elsif ($type eq "c") { # byte
push @{ $addr }, CORE::unpack("C",
substr($self->{"TI"},$self->{$cx},1));
$self->{$cx} += 1;
} elsif ($type eq "f") { # double
my $double_bytes = substr($self->{"TI"},$self->{$cx},8);
$double_bytes = reversi($double_bytes) if $self->{"xendian"};
push @{ $addr }, CORE::unpack("d", $double_bytes );
$self->{$cx} += 8;
} elsif ($type eq "I") { #int64
my $intbytes = substr($self->{"TI"},$self->{$cx},8);
$intbytes = reversi($intbytes) if $self->{"xendian"};
push @{ $addr }, CORE::unpack("q", $intbytes);
$self->{$cx} += 8;
} elsif ($type eq "U") { #uint64
my $intbytes = substr($self->{"TI"},$self->{$cx},8);
$intbytes = reversi($intbytes) if $self->{"xendian"};
push @{ $addr }, CORE::unpack("Q", $intbytes);
$self->{$cx} += 8;
}
}
} else {
# non-octothorpe (singleton)
if ($type eq "u") { # uint
${$addr} = CORE::unpack($self->{"UF"},
substr($self->{"TI"},$self->{$cx},4));
$self->{$cx} += 4;
} elsif ($type eq "i") { # int
# while perl's N or V conversions unpack an unsigned
# long from either big or little endian format
# respectively, when it comes to *signed* int, perl
# only has 'l' (which assumes native endianness).
# So we have to manually reverse the bytes in a
# cross-endian 'int' unpacking scenario.
my $intbytes = substr($self->{"TI"},$self->{$cx},4);
$intbytes = reversi($intbytes) if $self->{"xendian"};
${$addr} = CORE::unpack("l", $intbytes);
$self->{$cx} += 4;
} elsif ($type eq 'c') { # byte
${$c->[1]} = CORE::unpack("C",
substr($self->{"TI"},$self->{$cx},1));
$self->{$cx} += 1;
} elsif ($type eq 'f') { # double
${$addr} = CORE::unpack("d",
substr($self->{"TI"},$self->{$cx},8));
$self->{$cx} += 8;
} elsif ($type =~ /^(B|s)$/) { # string/binary
my $slen = CORE::unpack($self->{"UF"},
substr($self->{"TI"},$self->{$cx},4));
$self->{$cx} += 4;
${$addr} = CORE::unpack("a$slen",
substr($self->{"TI"},$self->{$cx},$slen));
$self->{$cx} += $slen;
} elsif ($type eq "I") { # int64
my $intbytes = substr($self->{"TI"},$self->{$cx},8);
$intbytes = reversi($intbytes) if $self->{"xendian"};
${$addr} = CORE::unpack("q", $intbytes);
$self->{$cx} += 8;
} elsif ($type eq "U") { # uint64
my $intbytes = substr($self->{"TI"},$self->{$cx},8);
$intbytes = reversi($intbytes) if $self->{"xendian"};
${$addr} = CORE::unpack("Q", $intbytes);
$self->{$cx} += 8;
} else { die "internal error"; }
}
} elsif ($c =~ /^A(\d+)$/) {
my $alen = $self->serlen($c,$self->{$cx});
$self->{"N$1"} = CORE::unpack($self->{"UF"},
substr($self->{"TI"},$self->{$cx},4)); # get array count
$self->{"C$1"} = $self->{$cx} + 4; # set array node's data start
$self->{$cx} += $alen; # step over array node's data
} else { die "internal error"; }
}
return $rc;
}
# specialized function to prepare root's child A nodes for initial use
sub unpackA0 {
my $self = shift;
my $ax = "A0";
my $cx = "C0";
my $c0 = $self->{$cx};
for my $c (@{ $self->{$ax} }) {
next if ref($c); # skip non-A nodes
if ($c =~ /^A(\d+)$/) {
my $alen = $self->serlen($c,$c0);
$self->{"N$1"} = CORE::unpack($self->{"UF"},
substr($self->{"TI"},$c0,4)); # get array count
$self->{"C$1"} = $c0 + 4; # set array node's data start
$c0 += $alen; # step over array node's data
} else { die "internal error"; }
}
}
# ascertain serialized length of given node by walking
sub serlen {
my $self = shift;
my $ax = shift;
my $dv = shift;
my $len = 0;
my $num;
if ($ax eq "A0") {
$num = 1;
} else {
return -1 unless $self->{"TL"} >= $dv + 4;
$num = CORE::unpack($self->{"UF"},substr($self->{"TI"},$dv,4));
$dv += 4;
$len += 4;
}
while ($num-- > 0) {
for my $c (@{ $self->{$ax} }) {
if (ref($c)) {
my $n = 1;
$n = $c->[2] if (@$c > 2); # octothorpic array length
if ($c->[0] =~ /^(i|u)$/) { # int/uint
return -1 unless $self->{"TL"} >= $dv + 4*$n;
$len += 4*$n;
$dv += 4*$n;
} elsif ($c->[0] eq "c") { # byte
return -1 unless $self->{"TL"} >= $dv + 1*$n;
$len += 1*$n;
$dv += 1*$n;
} elsif ($c->[0] eq "f") { # double
return -1 unless $self->{"TL"} >= $dv + 8*$n;
$len += 8*$n;
$dv += 8*$n;
} elsif ($c->[0] =~ /(I|U)/) { # int64/uint64
return -1 unless $self->{"TL"} >= $dv + 8*$n;
$len += 8*$n;
$dv += 8*$n;
} elsif ($c->[0] =~ /^(B|s)$/) { # string/binary
return -1 unless $self->{"TL"} >= $dv + 4;
my $slen = CORE::unpack($self->{"UF"},
substr($self->{"TI"},$dv,4));
$len += 4;
$dv += 4;
return -1 unless $self->{"TL"} >= $dv + $slen;
$len += $slen;
$dv += $slen;
} else { die "internal error" }
} elsif ($c =~ /^A/) {
my $alen = $self->serlen($c,$dv);
return -1 if $alen == -1;
$dv += $alen;
$len += $alen;
} else { die "internal error"; }
}
}
return $len;
}
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