public suspend fun decodeChunked()

in ktor-http/ktor-http-cio/common/src/io/ktor/http/cio/ChunkedTransferEncoding.kt [57:107]
44 lines of code
15 McCabe index (conditional complexity)

public suspend fun decodeChunked(input: ByteReadChannel, out: ByteWriteChannel, contentLength: Long) {
    val chunkSizeBuffer = ChunkSizeBufferPool.borrow()
    var totalBytesCopied = 0L

    try {
        while (true) {
            chunkSizeBuffer.clear()
            if (!input.readUTF8LineTo(chunkSizeBuffer, MAX_CHUNK_SIZE_LENGTH)) {
                throw EOFException("Chunked stream has ended unexpectedly: no chunk size")
            } else if (chunkSizeBuffer.isEmpty()) {
                throw EOFException("Invalid chunk size: empty")
            }

            val chunkSize =
                if (chunkSizeBuffer.length == 1 && chunkSizeBuffer[0] == '0') 0
                else chunkSizeBuffer.parseHexLong()

            if (contentLength != -1L && chunkSize > (contentLength - totalBytesCopied)) {
                input.cancel()
                throw ParserException("Invalid chunk: chunk-encoded content is larger than expected $contentLength")
            }

            if (chunkSize > 0) {
                input.copyTo(out, chunkSize)
                out.flush()
                totalBytesCopied += chunkSize
            }

            chunkSizeBuffer.clear()
            if (!input.readUTF8LineTo(chunkSizeBuffer, 2)) {
                throw EOFException("Invalid chunk: content block of size $chunkSize ended unexpectedly")
            }
            if (chunkSizeBuffer.isNotEmpty()) {
                throw EOFException("Invalid chunk: content block should end with CR+LF")
            }

            if (chunkSize == 0L) break
        }

        if (contentLength != -1L && totalBytesCopied != contentLength) {
            input.cancel()
            throw EOFException("Corrupted chunk-encoded content: steam ended before the expected number of bytes ($contentLength) were decoded.")
        }
    } catch (t: Throwable) {
        out.close(t)
        throw t
    } finally {
        ChunkSizeBufferPool.recycle(chunkSizeBuffer)
        out.close()
    }
}