45;&gt;</span> <span>unit Ctypes_static.ptr</span> <span>&#45;&gt;</span> Unsigned.size_t <span>&#45;&gt;</span> Unsigned.size_t</code></dt><dd><p><code>sha256 util input input_len output output_len</code></p><p>Calculates the SHA-256 hash of the input and encodes it as base64. If the output buffer is smaller than olm_sha256_length() then olm_utility_last_error() will be &quot;OUTPUT_BUFFER_TOO_SMALL&quot;.</p></dd></dl><dl><dt class="spec value" id="val-ed25519_verify"><a href="#val-ed25519_verify" class="