| … | |
… | |
| 64 | |
64 | |
| 65 | package CBOR::XS; |
65 | package CBOR::XS; |
| 66 | |
66 | |
| 67 | use common::sense; |
67 | use common::sense; |
| 68 | |
68 | |
| 69 | our $VERSION = '1.0'; |
69 | our $VERSION = 1.25; |
| 70 | our @ISA = qw(Exporter); |
70 | our @ISA = qw(Exporter); |
| 71 | |
71 | |
| 72 | our @EXPORT = qw(encode_cbor decode_cbor); |
72 | our @EXPORT = qw(encode_cbor decode_cbor); |
| 73 | |
73 | |
| 74 | use Exporter; |
74 | use Exporter; |
| … | |
… | |
| 242 | the standard CBOR way. |
242 | the standard CBOR way. |
| 243 | |
243 | |
| 244 | This option does not affect C<decode> in any way - string references will |
244 | This option does not affect C<decode> in any way - string references will |
| 245 | always be decoded properly if present. |
245 | always be decoded properly if present. |
| 246 | |
246 | |
|
|
247 | =item $cbor = $cbor->validate_utf8 ([$enable]) |
|
|
248 | |
|
|
249 | =item $enabled = $cbor->get_validate_utf8 |
|
|
250 | |
|
|
251 | If C<$enable> is true (or missing), then C<decode> will validate that |
|
|
252 | elements (text strings) containing UTF-8 data in fact contain valid UTF-8 |
|
|
253 | data (instead of blindly accepting it). This validation obviously takes |
|
|
254 | extra time during decoding. |
|
|
255 | |
|
|
256 | The concept of "valid UTF-8" used is perl's concept, which is a superset |
|
|
257 | of the official UTF-8. |
|
|
258 | |
|
|
259 | If C<$enable> is false (the default), then C<decode> will blindly accept |
|
|
260 | UTF-8 data, marking them as valid UTF-8 in the resulting data structure |
|
|
261 | regardless of whether thats true or not. |
|
|
262 | |
|
|
263 | Perl isn't too happy about corrupted UTF-8 in strings, but should |
|
|
264 | generally not crash or do similarly evil things. Extensions might be not |
|
|
265 | so forgiving, so it's recommended to turn on this setting if you receive |
|
|
266 | untrusted CBOR. |
|
|
267 | |
|
|
268 | This option does not affect C<encode> in any way - strings that are |
|
|
269 | supposedly valid UTF-8 will simply be dumped into the resulting CBOR |
|
|
270 | string without checking whether that is, in fact, true or not. |
|
|
271 | |
| 247 | =item $cbor = $cbor->filter ([$cb->($tag, $value)]) |
272 | =item $cbor = $cbor->filter ([$cb->($tag, $value)]) |
| 248 | |
273 | |
| 249 | =item $cb_or_undef = $cbor->get_filter |
274 | =item $cb_or_undef = $cbor->get_filter |
| 250 | |
275 | |
| 251 | Sets or replaces the tagged value decoding filter (when C<$cb> is |
276 | Sets or replaces the tagged value decoding filter (when C<$cb> is |
| … | |
… | |
| 305 | and you need to know where the first CBOR string ends amd the next one |
330 | and you need to know where the first CBOR string ends amd the next one |
| 306 | starts. |
331 | starts. |
| 307 | |
332 | |
| 308 | CBOR::XS->new->decode_prefix ("......") |
333 | CBOR::XS->new->decode_prefix ("......") |
| 309 | => ("...", 3) |
334 | => ("...", 3) |
|
|
335 | |
|
|
336 | =back |
|
|
337 | |
|
|
338 | =head2 INCREMENTAL PARSING |
|
|
339 | |
|
|
340 | In some cases, there is the need for incremental parsing of JSON |
|
|
341 | texts. While this module always has to keep both CBOR text and resulting |
|
|
342 | Perl data structure in memory at one time, it does allow you to parse a |
|
|
343 | CBOR stream incrementally, using a similar to using "decode_prefix" to see |
|
|
344 | if a full CBOR object is available, but is much more efficient. |
|
|
345 | |
|
|
346 | It basically works by parsing as much of a CBOR string as possible - if |
|
|
347 | the CBOR data is not complete yet, the pasrer will remember where it was, |
|
|
348 | to be able to restart when more data has been accumulated. Once enough |
|
|
349 | data is available to either decode a complete CBOR value or raise an |
|
|
350 | error, a real decode will be attempted. |
|
|
351 | |
|
|
352 | A typical use case would be a network protocol that consists of sending |
|
|
353 | and receiving CBOR-encoded messages. The solution that works with CBOR and |
|
|
354 | about anything else is by prepending a length to every CBOR value, so the |
|
|
355 | receiver knows how many octets to read. More compact (and slightly slower) |
|
|
356 | would be to just send CBOR values back-to-back, as C<CBOR::XS> knows where |
|
|
357 | a CBOR value ends, and doesn't need an explicit length. |
|
|
358 | |
|
|
359 | The following methods help with this: |
|
|
360 | |
|
|
361 | =over 4 |
|
|
362 | |
|
|
363 | =item @decoded = $cbor->incr_parse ($buffer) |
|
|
364 | |
|
|
365 | This method attempts to decode exactly one CBOR value from the beginning |
|
|
366 | of the given C<$buffer>. The value is removed from the C<$buffer> on |
|
|
367 | success. When C<$buffer> doesn't contain a complete value yet, it returns |
|
|
368 | nothing. Finally, when the C<$buffer> doesn't start with something |
|
|
369 | that could ever be a valid CBOR value, it raises an exception, just as |
|
|
370 | C<decode> would. In the latter case the decoder state is undefined and |
|
|
371 | must be reset before being able to parse further. |
|
|
372 | |
|
|
373 | This method modifies the C<$buffer> in place. When no CBOR value can be |
|
|
374 | decoded, the decoder stores the current string offset. On the next call, |
|
|
375 | continues decoding at the place where it stopped before. For this to make |
|
|
376 | sense, the C<$buffer> must begin with the same octets as on previous |
|
|
377 | unsuccessful calls. |
|
|
378 | |
|
|
379 | You can call this method in scalar context, in which case it either |
|
|
380 | returns a decoded value or C<undef>. This makes it impossible to |
|
|
381 | distinguish between CBOR null values (which decode to C<undef>) and an |
|
|
382 | unsuccessful decode, which is often acceptable. |
|
|
383 | |
|
|
384 | =item @decoded = $cbor->incr_parse_multiple ($buffer) |
|
|
385 | |
|
|
386 | Same as C<incr_parse>, but attempts to decode as many CBOR values as |
|
|
387 | possible in one go, instead of at most one. Calls to C<incr_parse> and |
|
|
388 | C<incr_parse_multiple> can be interleaved. |
|
|
389 | |
|
|
390 | =item $cbor->incr_reset |
|
|
391 | |
|
|
392 | Resets the incremental decoder. This throws away any saved state, so that |
|
|
393 | subsequent calls to C<incr_parse> or C<incr_parse_multiple> start to parse |
|
|
394 | a new CBOR value from the beginning of the C<$buffer> again. |
|
|
395 | |
|
|
396 | This method can be caled at any time, but it I<must> be called if you want |
|
|
397 | to change your C<$buffer> or there was a decoding error and you want to |
|
|
398 | reuse the C<$cbor> object for future incremental parsings. |
| 310 | |
399 | |
| 311 | =back |
400 | =back |
| 312 | |
401 | |
| 313 | |
402 | |
| 314 | =head1 MAPPING |
403 | =head1 MAPPING |
| … | |
… | |
| 773 | perl core distribution (e.g. L<URI>), it is (currently) up to the user to |
862 | perl core distribution (e.g. L<URI>), it is (currently) up to the user to |
| 774 | provide these modules. The decoding usually fails with an exception if the |
863 | provide these modules. The decoding usually fails with an exception if the |
| 775 | required module cannot be loaded. |
864 | required module cannot be loaded. |
| 776 | |
865 | |
| 777 | =over 4 |
866 | =over 4 |
|
|
867 | |
|
|
868 | =item 0, 1 (date/time string, seconds since the epoch) |
|
|
869 | |
|
|
870 | These tags are decoded into L<Time::Piece> objects. The corresponding |
|
|
871 | C<Time::Piece::TO_CBOR> method always encodes into tag 1 values currently. |
|
|
872 | |
|
|
873 | The L<Time::Piece> API is generally surprisingly bad, and fractional |
|
|
874 | seconds are only accidentally kept intact, so watch out. On the plus side, |
|
|
875 | the module comes with perl since 5.10, which has to count for something. |
| 778 | |
876 | |
| 779 | =item 2, 3 (positive/negative bignum) |
877 | =item 2, 3 (positive/negative bignum) |
| 780 | |
878 | |
| 781 | These tags are decoded into L<Math::BigInt> objects. The corresponding |
879 | These tags are decoded into L<Math::BigInt> objects. The corresponding |
| 782 | C<Math::BigInt::TO_CBOR> method encodes "small" bigints into normal CBOR |
880 | C<Math::BigInt::TO_CBOR> method encodes "small" bigints into normal CBOR |
| … | |
… | |
| 947 | service. I put the contact address into my modules for a reason. |
1045 | service. I put the contact address into my modules for a reason. |
| 948 | |
1046 | |
| 949 | =cut |
1047 | =cut |
| 950 | |
1048 | |
| 951 | our %FILTER = ( |
1049 | our %FILTER = ( |
| 952 | # 0 # rfc4287 datetime, utf-8 |
1050 | 0 => sub { # rfc4287 datetime, utf-8 |
| 953 | # 1 # unix timestamp, any |
1051 | require Time::Piece; |
|
|
1052 | # Time::Piece::Strptime uses the "incredibly flexible date parsing routine" |
|
|
1053 | # from FreeBSD, which can't parse ISO 8601, RFC3339, RFC4287 or much of anything |
|
|
1054 | # else either. Whats incredibe over standard strptime totally escapes me. |
|
|
1055 | # doesn't do fractional times, either. sigh. |
|
|
1056 | # In fact, it's all a lie, it uses whatever strptime it wants, and of course, |
|
|
1057 | # they are all incomptible. The openbsd one simply ignores %z (but according to the |
|
|
1058 | # docs, it would be much more incredibly flexible indeed. If it worked, that is.). |
|
|
1059 | scalar eval { |
|
|
1060 | my $s = $_[1]; |
|
|
1061 | |
|
|
1062 | $s =~ s/Z$/+00:00/; |
|
|
1063 | $s =~ s/(\.[0-9]+)?([+-][0-9][0-9]):([0-9][0-9])$// |
|
|
1064 | or die; |
|
|
1065 | |
|
|
1066 | my $b = $1 - ($2 * 60 + $3) * 60; # fractional part + offset. hopefully |
|
|
1067 | my $d = Time::Piece->strptime ($s, "%Y-%m-%dT%H:%M:%S"); |
|
|
1068 | |
|
|
1069 | Time::Piece::gmtime ($d->epoch + $b) |
|
|
1070 | } || die "corrupted CBOR date/time string ($_[0])"; |
|
|
1071 | }, |
|
|
1072 | |
|
|
1073 | 1 => sub { # seconds since the epoch, possibly fractional |
|
|
1074 | require Time::Piece; |
|
|
1075 | scalar Time::Piece::gmtime (pop) |
|
|
1076 | }, |
| 954 | |
1077 | |
| 955 | 2 => sub { # pos bigint |
1078 | 2 => sub { # pos bigint |
| 956 | require Math::BigInt; |
1079 | require Math::BigInt; |
| 957 | Math::BigInt->new ("0x" . unpack "H*", pop) |
1080 | Math::BigInt->new ("0x" . unpack "H*", pop) |
| 958 | }, |
1081 | }, |
| … | |
… | |
| 994 | } |
1117 | } |
| 995 | |
1118 | |
| 996 | sub URI::TO_CBOR { |
1119 | sub URI::TO_CBOR { |
| 997 | my $uri = $_[0]->as_string; |
1120 | my $uri = $_[0]->as_string; |
| 998 | utf8::upgrade $uri; |
1121 | utf8::upgrade $uri; |
| 999 | CBOR::XS::tag 32, $uri |
1122 | tag 32, $uri |
| 1000 | } |
1123 | } |
| 1001 | |
1124 | |
| 1002 | sub Math::BigInt::TO_CBOR { |
1125 | sub Math::BigInt::TO_CBOR { |
| 1003 | if ($_[0] >= -2147483648 && $_[0] <= 2147483647) { |
1126 | if ($_[0] >= -2147483648 && $_[0] <= 2147483647) { |
| 1004 | $_[0]->numify |
1127 | $_[0]->numify |
| 1005 | } else { |
1128 | } else { |
| 1006 | my $hex = substr $_[0]->as_hex, 2; |
1129 | my $hex = substr $_[0]->as_hex, 2; |
| 1007 | $hex = "0$hex" if 1 & length $hex; # sigh |
1130 | $hex = "0$hex" if 1 & length $hex; # sigh |
| 1008 | CBOR::XS::tag $_[0] >= 0 ? 2 : 3, pack "H*", $hex |
1131 | tag $_[0] >= 0 ? 2 : 3, pack "H*", $hex |
| 1009 | } |
1132 | } |
| 1010 | } |
1133 | } |
| 1011 | |
1134 | |
| 1012 | sub Math::BigFloat::TO_CBOR { |
1135 | sub Math::BigFloat::TO_CBOR { |
| 1013 | my ($m, $e) = $_[0]->parts; |
1136 | my ($m, $e) = $_[0]->parts; |
| 1014 | CBOR::XS::tag 4, [$e->numify, $m] |
1137 | tag 4, [$e->numify, $m] |
|
|
1138 | } |
|
|
1139 | |
|
|
1140 | sub Time::Piece::TO_CBOR { |
|
|
1141 | tag 1, 0 + $_[0]->epoch |
| 1015 | } |
1142 | } |
| 1016 | |
1143 | |
| 1017 | XSLoader::load "CBOR::XS", $VERSION; |
1144 | XSLoader::load "CBOR::XS", $VERSION; |
| 1018 | |
1145 | |
| 1019 | =head1 SEE ALSO |
1146 | =head1 SEE ALSO |
