add cbor_value_ptr_{text,byte}_string #205
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Add functions to directly obtain a pointer to the data of a text or byte string, without the need to copy. Otherwise these are analogous to the corresponding _copy_ functions.
petm-dec
changed the title
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Zero-copy API is already implemented in dev...thiagomacieira:dev. I've just never published it because it doesn't work really well for microcontrollers. Since I haven't got the necessary help from them for that in the last 3 years, I'm simply going to ignore them and publish the API as-is. |
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Is there some way to help getting the new API merged?... What specifically doesn't work well for microcontrollers? |
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The problem is that TinyCBOR requires a single buffer with all of your data in it. On many small OSes (I know Zephyr), memory allocation is preferably done in chunks of a fixed size, so if you want for example 200 bytes, you get two 120-byte chunks and form a linked-list with them. The parsing API was meant to help fix that, but if you couple that with the string API, it gets messy. Suppose you have that 2x120-byte linked list and your string starts 5 bytes into the first one: how does the API return that information? |
Add functions to directly obtain a pointer to the data
of a text or byte string, without the need to copy.
Otherwise these are analogous to the corresponding copy functions.