libz_rs_sys

Function deflateParams

Source 
#[export_name = "deflateParams"]
pub unsafe extern "C-unwind" fn deflateParams(
    strm: z_streamp,
    level: c_int,
    strategy: c_int,
) -> c_int
Expand description

Dynamically update the compression level and compression strategy.

This can be used to switch between compression and straight copy of the input data, or to switch to a different kind of input data requiring a different strategy.

The interpretation of level and strategy is as in deflateInit2_.

§Returns

  • Z_OK if success
  • Z_STREAM_ERROR if the stream state was inconsistent or if a parameter was invalid
  • Z_BUF_ERROR if there was not enough output space to complete the compression of the available input data before a change in the strategy or approach.

Note that in the case of a Z_BUF_ERROR, the parameters are not changed. A return value of Z_BUF_ERROR is not fatal, in which case deflateParams can be retried with more output space.

§Safety

The caller must guarantee that

  • Either
    • strm is NULL
    • strm satisfies the requirements of &mut *strm and was initialized with deflateInit_ or similar