feat: c wrapper #2
Conversation
Some refactoring to allow creating libnegentropy.so shared library
Actually char* is nothing but a representation of memory. Null terminated chars cause trouble only when you start using operations like length or copying a char*. since underlying implementation is c++ which uses std::string which inturn supports null chars in string, this should not be a problem. But to ensure this doesn't cause an issue, i will add a test to validate this. And yes, in C blobs are generally passed around as char* along with a len param. |
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| result->have_ids_len = haveIds.size(); | ||
| result->need_ids_len = needIds.size(); | ||
| result->have_ids = (buffer*)malloc(result->have_ids_len*sizeof(buffer)); |
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Where is this memory being released?
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I had implemented a free_result function which releases memory for all these buffers.
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| //Note: This function assumes that all relevant heap memory is alloced and just tries to free | ||
| void free_result(result* r){ |
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ah I see, yes I think it is necessary to explore the callback approach that we have mentioned. This might bring mem leaks in the future.
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Yep, this is a stop-gap approach as callbacks are having additional trouble in nim.
I could not use a closure based callback and hence took this approach to begin with.
I will test a callback model in sample code and then migrate to callback approach(which will not involve such memory leak issues). Also in callback i could use stack memory for many things and reduce amount of heap allocations.
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Merging this as will take up pending items in a separate PR. |
As integrating a c++ library to nim has some drawbacks, approach taken is to write a C API wrapper to be integrated into nwaku.
To that end, all required functionalities have been wrapped into C API.
Tasks:
Following shall be taken up separately as this PR is becoming huge: