The function cCamSlot::Decrypt() can now also be called with Data == NULL

HISTORY

@@ -8925,7 +8925,7 @@ Video Disk Recorder Revision History
 - Now stopping any ongoing recordings before stopping the plugins, to avoid
   a crash when stopping VDR while recording.
 
-2017-04-06: Version 2.3.4
+2017-04-15: Version 2.3.4
 
 - The functionality of HandleRemoteModifications(), which synchronizes changes to
   timers between peer VDR machines, has been moved to timers.[ch] and renamed to
@@ -8965,3 +8965,10 @@ Video Disk Recorder Revision History
   recording being replayed.
 - Signal strength and quality (CNR) are now determined via DVB API 5 (if available).
   Fallback is the old DVB API 3 method.
+- The function cCamSlot::Decrypt() can now also be called with Data == NULL.
+  This is necessary to allow CAMs that copy the incoming data into a separate buffer
+  to return previously received and decrypted TS packets. See ci.h for details.
+  Plugins that implement a derived cCamSlot need to properly handle this case, and
+  plugins that implement a derived cDevice need to call Decrypt() in their
+  GetTSPacket() function even if the incoming buffer is currently empty (see
+  cDvbDevice::GetTSPacket()).

ci.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: ci.c 4.10 2017/04/02 10:02:13 kls Exp $
+ * $Id: ci.c 4.11 2017/04/11 16:45:55 kls Exp $
  */
 
 #include "ci.h"
@@ -2415,7 +2415,8 @@ bool cCamSlot::IsDecrypting(void)
 
 uchar *cCamSlot::Decrypt(uchar *Data, int &Count)
 {
-  Count = TS_SIZE;
+  if (Data)
+     Count = TS_SIZE;
   return Data;
 }
 

ci.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: ci.h 4.5 2017/03/23 14:23:33 kls Exp $
+ * $Id: ci.h 4.6 2017/04/10 09:17:56 kls Exp $
  */
 
 #ifndef __CI_H
@@ -345,7 +345,12 @@ public:
        ///< in hardware, it can implement this function to be given access
        ///< to the data in the device's TS buffer. Data points to a buffer
        ///< of Count bytes of TS data. The first byte in Data is guaranteed
-       ///< to be a TS_SYNC_BYTE.
+       ///< to be a TS_SYNC_BYTE, and Count is at least TS_SIZE.
+       ///< Note that Decrypt() may be called with Data == NULL! This is necessary
+       ///< to allow CAMs that copy the incoming data into a separate buffer to
+       ///< return previously received and decrypted TS packets. If Data is NULL,
+       ///< Count is 0 and must not be modified, and the return value shall point to the
+       ///< next available decrypted TS packet (if any).
        ///< There are three possible ways a CAM can handle decryption:
        ///< 1. If the full TS data is physically routed through the CAM in hardware,
        ///< there is no need to reimplement this function.

device.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: device.c 4.12 2017/04/02 10:08:49 kls Exp $
+ * $Id: device.c 4.13 2017/04/14 09:38:42 kls Exp $
  */
 
 #include "device.h"
@@ -1860,13 +1860,15 @@ void cTSBuffer::Action(void)
      }
 }
 
-uchar *cTSBuffer::Get(int *Available)
+uchar *cTSBuffer::Get(int *Available, bool CheckAvailable)
 {
   int Count = 0;
   if (delivered) {
      ringBuffer->Del(TS_SIZE);
      delivered = false;
      }
+  if (CheckAvailable && ringBuffer->Available() < TS_SIZE)
+     return NULL;
   uchar *p = ringBuffer->Get(Count);
   if (p && Count >= TS_SIZE) {
      if (*p != TS_SYNC_BYTE) {

device.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: device.h 4.5 2017/04/02 10:08:49 kls Exp $
+ * $Id: device.h 4.6 2017/04/14 09:59:20 kls Exp $
  */
 
 #ifndef __DEVICE_H
@@ -846,13 +846,17 @@ private:
 public:
   cTSBuffer(int File, int Size, int CardIndex);
   virtual ~cTSBuffer();
-  uchar *Get(int *Available = NULL);
+  uchar *Get(int *Available = NULL, bool CheckAvailable = false);
      ///< Returns a pointer to the first TS packet in the buffer. If Available is given,
      ///< it will return the total number of consecutive bytes pointed to in the buffer.
      ///< It is guaranteed that the returned pointer points to a TS_SYNC_BYTE and that
      ///< there are at least TS_SIZE bytes in the buffer. Otherwise NULL will be
      ///< returned and the value in Available (if given) is undefined.
      ///< Each call to Get() returns a pointer to the next TS packet in the buffer.
+     ///< If CheckAvailable is true, the buffer will be checked whether it contains
+     ///< at least TS_SIZE bytes before trying to get any data from it. Otherwise, if
+     ///< the buffer is empty, this function will wait a little while for the buffer
+     ///< to be filled again.
   void Skip(int Count);
      ///< If after a call to Get() more or less than TS_SIZE of the available data
      ///< has been processed, a call to Skip() with the number of processed bytes

dvbdevice.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: dvbdevice.c 4.5 2017/04/06 17:02:35 kls Exp $
+ * $Id: dvbdevice.c 4.6 2017/04/14 10:05:15 kls Exp $
  */
 
 #include "dvbdevice.h"
@@ -1187,6 +1187,7 @@ cDvbDevice::cDvbDevice(int Adapter, int Frontend)
   fd_ca = DvbOpen(DEV_DVB_CA, adapter, frontend, O_RDWR);
   if (fd_ca >= 0)
      ciAdapter = cDvbCiAdapter::CreateCiAdapter(this, fd_ca);
+  checkTsBuffer = false;
 
   // The DVR device (will be opened and closed as needed):
 
@@ -1763,11 +1764,12 @@ bool cDvbDevice::GetTSPacket(uchar *&Data)
      if (cCamSlot *cs = CamSlot()) {
         if (cs->WantsTsData()) {
            int Available;
-           Data = tsBuffer->Get(&Available);
-           if (Data) {
-              Data = cs->Decrypt(Data, Available);
-              tsBuffer->Skip(Available);
-              }
+           Data = tsBuffer->Get(&Available, checkTsBuffer);
+           if (!Data)
+              Available = 0;
+           Data = cs->Decrypt(Data, Available);
+           tsBuffer->Skip(Available);
+           checkTsBuffer = Data != NULL;
            return true;
            }
         }

dvbdevice.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: dvbdevice.h 4.1 2015/04/18 13:57:27 kls Exp $
+ * $Id: dvbdevice.h 4.2 2017/04/14 09:31:29 kls Exp $
  */
 
 #ifndef __DVBDEVICE_H
@@ -187,6 +187,7 @@ private:
   int numDeliverySystems;
   int numModulations;
   int fd_dvr, fd_ca;
+  bool checkTsBuffer;
   static cMutex bondMutex;
   cDvbDevice *bondedDevice;
   mutable bool needsDetachBondedReceivers;