Function zstd_sys::ZSTD_getDecompressedSize

pub unsafe extern "C" fn ZSTD_getDecompressedSize(
    src: *const c_void, 
    srcSize: usize
) -> c_ulonglong

ZSTD_getDecompressedSize() : * NOTE: This function is planned to be obsolete, in favour of ZSTD_getFrameContentSize. * ZSTD_getFrameContentSize functions the same way, returning the decompressed size of a single * frame, but distinguishes empty frames from frames with an unknown size, or errors. * * Additionally, ZSTD_findDecompressedSize can be used instead. It can handle multiple * concatenated frames in one buffer, and so is more general. * As a result however, it requires more computation and entire frames to be passed to it, * as opposed to ZSTD_getFrameContentSize which requires only a single frame's header. * * 'src' is the start of a zstd compressed frame. * @return : content size to be decompressed, as a 64-bits value if known, 0 otherwise. * note 1 : decompressed size is an optional field, that may not be present, especially in streaming mode. * When return==0, data to decompress could be any size. * In which case, it's necessary to use streaming mode to decompress data. * Optionally, application can still use ZSTD_decompress() while relying on implied limits. * (For example, data may be necessarily cut into blocks <= 16 KB). * note 2 : decompressed size is always present when compression is done with ZSTD_compress() * note 3 : decompressed size can be very large (64-bits value), * potentially larger than what local system can handle as a single memory segment. * In which case, it's necessary to use streaming mode to decompress data. * note 4 : If source is untrusted, decompressed size could be wrong or intentionally modified. * Always ensure result fits within application's authorized limits. * Each application can set its own limits. * note 5 : when return==0, if precise failure cause is needed, use ZSTD_getFrameParams() to know more.