Function DoTransfer

engine/dlib/src/dlib/http_client.cpp:711–804

    }

    static Result DoTransfer(HClient client, Response* response, int to_transfer, HttpContent http_content, bool add_to_cache, const char* method)
    {
        // to_transfer can be set to -1 when the "Content-Length" is unknown
        int total_transferred = 0;

#if defined(DM_NO_HTTP_CACHE)
        (void) add_to_cache;
#endif

        while (true)
        {
            int n;
            if (to_transfer == -1) {
                // Unknown "Content-Length". Read as much as we can.
                n = response->m_TotalReceived - response->m_ContentOffset;
            } else {
                n = dmMath::Min(to_transfer - total_transferred, response->m_TotalReceived - response->m_ContentOffset);
            }
            http_content(response, client->m_Userdata, response->m_Status, client->m_Buffer + response->m_ContentOffset, n, response->m_ContentLength,
                        response->m_RangeStart, response->m_RangeEnd, response->m_DocumentSize,
                        method);

#if !defined(DM_NO_HTTP_CACHE)
            if (response->m_CacheCreator && add_to_cache)
            {
                dmHttpCache::Add(client->m_HttpCache, response->m_CacheCreator, client->m_Buffer + response->m_ContentOffset, n);
            }
#endif

            total_transferred += n;
            assert(total_transferred <= to_transfer || to_transfer == -1);
            response->m_ContentOffset += n;

            if (total_transferred == to_transfer)
            {
                // Move "extra" bytes to buffer start
                memmove(client->m_Buffer, client->m_Buffer + response->m_ContentOffset, response->m_TotalReceived - response->m_ContentOffset);
                response->m_TotalReceived = response->m_TotalReceived - response->m_ContentOffset;
                response->m_ContentOffset = 0;
                break;
            }

            assert(response->m_TotalReceived - response->m_ContentOffset == 0);
            response->m_ContentOffset = 0;
            response->m_TotalReceived = 0;

            int recv_bytes;
            dmSocket::Result sock_res = Receive(response, client->m_Buffer, BUFFER_SIZE, &recv_bytes);

            if( sock_res == dmSocket::RESULT_WOULDBLOCK )
            {
                sock_res = dmSocket::RESULT_TRY_AGAIN;
            }
            if( (sock_res == dmSocket::RESULT_OK || sock_res == dmSocket::RESULT_TRY_AGAIN) && HasRequestTimedOut(client) )
            {
                sock_res = dmSocket::RESULT_WOULDBLOCK;
            }