Function gzsetparams

zlib/gzwrite.c:630–664

-- see zlib.h -- */

/* -- see zlib.h -- */
int ZEXPORT gzsetparams(gzFile file, int level, int strategy) {
    gz_statep state;
    z_streamp strm;

    /* get internal structure */
    if (file == NULL)
        return Z_STREAM_ERROR;
    state = (gz_statep)file;
    strm = &(state->strm);

    /* check that we're compressing and that there's no (serious) error */
    if (state->mode != GZ_WRITE || (state->err != Z_OK && !state->again) ||
            state->direct)
        return Z_STREAM_ERROR;
    gz_error(state, Z_OK, NULL);

    /* if no change is requested, then do nothing */
    if (level == state->level && strategy == state->strategy)
        return Z_OK;

    /* check for seek request */
    if (state->skip && gz_zero(state) == -1)
        return state->err;

    /* change compression parameters for subsequent input */
    if (state->size) {
        /* flush previous input with previous parameters before changing */
        if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
            return state->err;
        deflateParams(strm, level, strategy);
    }
    state->level = level;
    state->strategy = strategy;
    return Z_OK;
}

/* -- see zlib.h -- */
int ZEXPORT gzclose_w(gzFile file) {