Function zstd_sys::ZSTD_estimateCCtxSize [] [src]

pub unsafe extern "C" fn ZSTD_estimateCCtxSize(compressionLevel: c_int) -> usize

ZSTD_estimate*() : These functions make it possible to estimate memory usage of a future {D,C}Ctx, before its creation. ZSTD_estimateCCtxSize() will provide a budget large enough for any compression level up to selected one. It will also consider src size to be arbitrarily "large", which is worst case. If srcSize is known to always be small, ZSTD_estimateCCtxSize_usingCParams() can provide a tighter estimation. ZSTD_estimateCCtxSize_usingCParams() can be used in tandem with ZSTD_getCParams() to create cParams from compressionLevel. ZSTD_estimateCCtxSize_usingCCtxParams() can be used in tandem with ZSTD_CCtxParam_setParameter(). Only single-threaded compression is supported. This function will return an error code if ZSTD_p_nbThreads is > 1. Note : CCtx estimation is only correct for single-threaded compression