| … | |
… | |
| 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 = 1.86; |
69 | our $VERSION = 1.87; |
| 70 | our @ISA = qw(Exporter); |
70 | our @ISA = qw(Exporter); |
| 71 | |
71 | |
| 72 | our @EXPORT = qw(encode_cbor decode_cbor); |
72 | our @EXPORT = qw(encode_cbor decode_cbor); |
| 73 | |
73 | |
| 74 | use Exporter; |
74 | use Exporter; |
| … | |
… | |
| 216 | communication partner supports the value sharing extensions to CBOR |
216 | communication partner supports the value sharing extensions to CBOR |
| 217 | (L<http://cbor.schmorp.de/value-sharing>), as without decoder support, the |
217 | (L<http://cbor.schmorp.de/value-sharing>), as without decoder support, the |
| 218 | resulting data structure might be unusable. |
218 | resulting data structure might be unusable. |
| 219 | |
219 | |
| 220 | Detecting shared values incurs a runtime overhead when values are encoded |
220 | Detecting shared values incurs a runtime overhead when values are encoded |
| 221 | that have a reference counter large than one, and might unnecessarily |
221 | that have a reference counter larger than one, and might unnecessarily |
| 222 | increase the encoded size, as potentially shared values are encoded as |
222 | increase the encoded size, as potentially shared values are encoded as |
| 223 | shareable whether or not they are actually shared. |
223 | shareable whether or not they are actually shared. |
| 224 | |
224 | |
| 225 | At the moment, only targets of references can be shared (e.g. scalars, |
225 | At the moment, only targets of references can be shared (e.g. scalars, |
| 226 | arrays or hashes pointed to by a reference). Weirder constructs, such as |
226 | arrays or hashes pointed to by a reference). Weirder constructs, such as |
| … | |
… | |
| 245 | isn't prepared for this will not leak memory. |
245 | isn't prepared for this will not leak memory. |
| 246 | |
246 | |
| 247 | If C<$enable> is false (the default), then C<decode> will throw an error |
247 | If C<$enable> is false (the default), then C<decode> will throw an error |
| 248 | when it encounters a self-referential/cyclic data structure. |
248 | when it encounters a self-referential/cyclic data structure. |
| 249 | |
249 | |
| 250 | FUTURE DIRECTION: the motivation behind this option is to avoid I<real> |
250 | This option does not affect C<encode> in any way - shared values and |
| 251 | cycles - future versions of this module might chose to decode cyclic data |
251 | references will always be encoded properly if present. |
| 252 | structures using weak references when this option is off, instead of |
252 | |
| 253 | throwing an error. |
253 | =item $cbor = $cbor->allow_weak_cycles ([$enable]) |
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254 | |
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255 | =item $enabled = $cbor->get_allow_weak_cycles |
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256 | |
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257 | This works like C<allow_cycles> in that it allows the resulting data |
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258 | structures to contain cycles, but unlike C<allow_cycles>, those cyclic |
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259 | rreferences will be weak. That means that code that recurrsively walks |
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260 | the data structure must be prepared with cycles, but at least not special |
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261 | precautions must be implemented to free these data structures. |
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262 | |
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263 | Only those references leading to actual cycles will be weakened - other |
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264 | references, e.g. when the same hash or arrray is referenced multiple times |
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265 | in an arrray, will be normal references. |
| 254 | |
266 | |
| 255 | This option does not affect C<encode> in any way - shared values and |
267 | This option does not affect C<encode> in any way - shared values and |
| 256 | references will always be encoded properly if present. |
268 | references will always be encoded properly if present. |
| 257 | |
269 | |
| 258 | =item $cbor = $cbor->forbid_objects ([$enable]) |
270 | =item $cbor = $cbor->forbid_objects ([$enable]) |
