Fixed sound buffering issues with compressed formats

(cherry picked from commit d9d22aa42207e4d8e23ec5337bce83f87726cd20)

diff --git a/channels/rdpsnd/client/rdpsnd_main.c b/channels/rdpsnd/client/rdpsnd_main.c
index 43bbbc5..c6d193e 100644 (file)
--- a/channels/rdpsnd/client/rdpsnd_main.c
+++ b/channels/rdpsnd/client/rdpsnd_main.c
@@ -495,6 +495,38 @@ static BOOL rdpsnd_detect_overrun(rdpsndPlugin* rdpsnd, const AUDIO_FORMAT* form
        if (!rdpsnd || !format)
                return FALSE;
 
+       /* Older windows RDP servers do not limit the send buffer, which can
+        * cause quite a large amount of sound data buffered client side.
+        * If e.g. sound is paused server side the client will keep playing
+        * for a long time instead of pausing playback.
+        *
+        * To avoid this we check:
+        *
+        * 1. Is the sound sample received from a known format these servers
+        *    support
+        * 2. If it is calculate the size of the client side sound buffer
+        * 3. If the buffer is too large silently drop the sample which will
+        *    trigger a retransmit later on.
+        *
+        * This check must only be applied to these known formats, because
+        * with newer and other formats the sample size can not be calculated
+        * without decompressing the sample first.
+        */
+       switch (format->wFormatTag)
+       {
+               case WAVE_FORMAT_PCM:
+               case WAVE_FORMAT_DVI_ADPCM:
+               case WAVE_FORMAT_ADPCM:
+               case WAVE_FORMAT_ALAW:
+               case WAVE_FORMAT_MULAW:
+                       break;
+               case WAVE_FORMAT_MSG723:
+               case WAVE_FORMAT_GSM610:
+               case WAVE_FORMAT_AAC_MS:
+               default:
+                       return FALSE;
+       }
+
        audio_format_print(WLog_Get(TAG), WLOG_DEBUG, format);
        bpf = format->nChannels * format->wBitsPerSample * format->nSamplesPerSec / 8;
        if (bpf == 0)
@@ -634,9 +666,9 @@ static UINT rdpsnd_recv_wave2_pdu(rdpsndPlugin* rdpsnd, wStream* s, UINT16 BodyS
        rdpsnd->waveDataSize = BodySize - 12;
        rdpsnd->wArrivalTime = GetTickCount64();
        WLog_Print(rdpsnd->log, WLOG_DEBUG,
-                  "%s Wave2PDU: cBlockNo: %" PRIu8 " wFormatNo: %" PRIu16 ", align=%hu",
+                  "%s Wave2PDU: cBlockNo: %" PRIu8 " wFormatNo: %" PRIu16 " [%s] , align=%hu",
                   rdpsnd_is_dyn_str(rdpsnd->dynamic), rdpsnd->cBlockNo, wFormatNo,
-                  format->nBlockAlign);
+                  audio_format_get_tag_string(format->wFormatTag), format->nBlockAlign);
 
        if (!rdpsnd_ensure_device_is_open(rdpsnd, wFormatNo, format))
                return ERROR_INTERNAL_ERROR;