When remote timers are fetched from a peer VDR, we no longer blindly delete and re-add them, but rather compare them and make only the minimum necessary changes

HISTORY

@@ -9162,7 +9162,7 @@ Video Disk Recorder Revision History
   a subdirectory.
 - SVDRP peering can now be limited to the default SVDRP host (see MANUAL for details).
 
-2018-02-27: Version 2.3.9
+2018-02-28: Version 2.3.9
 
 - Updated the Italian OSD texts (thanks to Diego Pierotto).
 - Updated the Finnish OSD texts (thanks to Rolf Ahrenberg).
@@ -9286,3 +9286,5 @@ Video Disk Recorder Revision History
 - Moved handling remote timers into cSVDRPClientHandler::ProcessConnections().
 - Combined Start/StopSVDRPServer/ClientHandler() into Start/StopSVDRPHandler().
 - Updated the Polish OSD texts (thanks to Tomasz Maciej Nowak).
+- When remote timers are fetched from a peer VDR, we no longer blindly delete and re-add
+  them, but rather compare them and make only the minimum necessary changes.

svdrp.c

@@ -10,7 +10,7 @@
  * and interact with the Video Disk Recorder - or write a full featured
  * graphical interface that sits on top of an SVDRP connection.
  *
- * $Id: svdrp.c 4.30 2018/02/26 15:42:15 kls Exp $
+ * $Id: svdrp.c 4.31 2018/02/28 10:04:00 kls Exp $
  */
 
 #include "svdrp.h"
@@ -483,8 +483,23 @@ bool cSVDRPClient::HasFetchFlag(eSvdrpFetchFlags Flag)
 
 bool cSVDRPClient::GetRemoteTimers(cStringList &Response)
 {
-  if (HasFetchFlag(sffTimers))
-     return Execute("LSTT ID", &Response);
+  if (HasFetchFlag(sffTimers)) {
+     if (Execute("LSTT ID", &Response)) {
+        for (int i = 0; i < Response.Size(); i++) {
+            char *s = Response[i];
+            int Code = SVDRPCode(s);
+            if (Code == 250)
+               strshift(s, 4);
+            else {
+               if (Code != 550)
+                  esyslog("ERROR: %s: %s", ServerName(), s);
+               return false;
+               }
+            }
+        Response.SortNumerically();
+        return true;
+        }
+     }
   return false;
 }
 

timers.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: timers.c 4.15 2018/02/25 13:05:03 kls Exp $
+ * $Id: timers.c 4.16 2018/02/28 10:05:52 kls Exp $
  */
 
 #include "timers.h"
@@ -900,9 +900,9 @@ bool cTimers::DeleteExpired(void)
 
 bool cTimers::StoreRemoteTimers(const char *ServerName, const cStringList *RemoteTimers)
 {
-  //TODO handle only new/deleted/modified timers?
   bool Result = false;
-  // Delete old remote timers:
+  if (!ServerName || !RemoteTimers || RemoteTimers->Size() == 0) {
+     // Remove remote timers from this list:
      cTimer *Timer = First();
      while (Timer) {
            cTimer *t = Next(Timer);
@@ -912,20 +912,73 @@ bool cTimers::StoreRemoteTimers(const char *ServerName, const cStringList *Remot
               }
            Timer = t;
            }
-  // Add new remote timers:
-  if (ServerName && RemoteTimers) {
-     for (int i = 0; i < RemoteTimers->Size(); i++) {
-         const char *s = (*RemoteTimers)[i];
-         int Code = SVDRPCode(s);
-         if (Code == 250) {
-            if (const char *v = SVDRPValue(s)) {
-               int Id = atoi(v);
+     return Result;
+     }
+  // Collect all locally stored remote timers from ServerName:
+  cStringList tl;
+  for (cTimer *ti = First(); ti; ti = Next(ti)) {
+      if (ti->Remote() && strcmp(ti->Remote(), ServerName) == 0)
+         tl.Append(strdup(cString::sprintf("%d %s", ti->Id(), *ti->ToText(true))));
+      }
+  tl.SortNumerically(); // RemoteTimers is also sorted numerically!
+  // Compare the two lists and react accordingly:
+  int il = 0; // index into the local ("left") list of remote timers
+  int ir = 0; // index into the remote ("right") list of timers
+  int sl = tl.Size();
+  int sr = RemoteTimers->Size();
+  for (;;) {
+      int AddTimer = 0;
+      int DelTimer = 0;
+      if (il < sl) { // still have left entries
+         int nl = atoi(tl[il]);
+         if (ir < sr) { // still have right entries
+            // Compare timers:
+            int nr = atoi((*RemoteTimers)[ir]);
+            if (nl == nr) // same timer id
+               AddTimer = DelTimer = nl;
+            else if (nl < nr) // left entry not in right list
+               DelTimer = nl;
+            else // right entry not in left list
+               AddTimer = nr;
+            }
+         else // processed all right entries
+            DelTimer = nl;
+         }
+      else if (ir < sr) // still have right entries
+         AddTimer = atoi((*RemoteTimers)[ir]);
+      else // processed all left and right entries
+         break;
+      if (AddTimer && DelTimer) {
+         if (strcmp(tl[il], (*RemoteTimers)[ir]) != 0) {
+            // Overwrite timer:
+            char *v = (*RemoteTimers)[ir];
+            while (*v && *v != ' ')
+                  v++; // skip id
+            if (cTimer *l = GetById(DelTimer, ServerName)) {
+               cTimer r;
+               if (r.Parse(v)) {
+                  r.SetRemote(ServerName);
+                  r.SetId(AddTimer);
+                  *l = r;
+                  Result = true;
+                  }
+               else
+                  esyslog("ERROR: %s: error in timer settings: %s", ServerName, v);
+               }
+            }
+         else // identical timer, nothing to do
+            ;
+         il++;
+         ir++;
+         }
+      else if (AddTimer) {
+         char *v = (*RemoteTimers)[ir];
          while (*v && *v != ' ')
                v++; // skip id
          cTimer *Timer = new cTimer;
          if (Timer->Parse(v)) {
             Timer->SetRemote(ServerName);
-                  Timer->SetId(Id);
+            Timer->SetId(AddTimer);
             Add(Timer);
             Result = true;
             }
@@ -933,10 +986,14 @@ bool cTimers::StoreRemoteTimers(const char *ServerName, const cStringList *Remot
             esyslog("ERROR: %s: error in timer settings: %s", ServerName, v);
             delete Timer;
             }
+         ir++;
          }
+      else if (DelTimer) {
+         if (cTimer *t = GetById(DelTimer, ServerName)) {
+            Del(t);
+            Result = true;
             }
-         else if (Code != 550)
-            esyslog("ERROR: %s: %s", ServerName, s);
+         il++;
          }
       }
   return Result;

timers.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: timers.h 4.10 2018/02/25 12:54:55 kls Exp $
+ * $Id: timers.h 4.11 2018/02/27 13:57:26 kls Exp $
  */
 
 #ifndef __TIMERS_H
@@ -190,7 +190,9 @@ public:
       ///< this list. If no ServerName is given, all remote timers from all peer machines
       ///< will be removed from this list. If no RemoteTimers are given, only the remote
       ///< timers from ServerName will be removed from this list.
-      ///< Returns true if any remote timers have been added or deleted
+      ///< The given list of RemoteTimers must be sorted numerically (by a call to its
+      ///< SortNumerically() function).
+      ///< Returns true if any remote timers have been added, deleted or modified.
   };
 
 bool HandleRemoteTimerModifications(cTimer *NewTimer, cTimer *OldTimer = NULL, cString *Msg = NULL);

tools.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.c 4.8 2017/06/25 11:45:39 kls Exp $
+ * $Id: tools.c 4.9 2018/02/27 10:09:21 kls Exp $
  */
 
 #include "tools.h"
@@ -296,6 +296,18 @@ cString strgetval(const char *s, const char *name, char d)
   return NULL;
 }
 
+char *strshift(char *s, int n)
+{
+  if (s && n > 0) {
+     int l = strlen(s);
+     if (n < l)
+        memmove(s, s + n, l - n + 1); // we also copy the terminating 0!
+     else
+        *s = 0;
+     }
+  return s;
+}
+
 bool startswith(const char *s, const char *p)
 {
   while (*p) {

tools.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.h 4.13 2017/06/25 11:45:38 kls Exp $
+ * $Id: tools.h 4.14 2018/02/28 10:06:47 kls Exp $
  */
 
 #ifndef __TOOLS_H
@@ -226,6 +226,12 @@ cString strgetval(const char *s, const char *name, char d = '=');
     ///< If an other delimiter shall be used (like, e.g., ':'), it can be given
     ///< as the third parameter.
     ///< If name occurs more than once in s, only the first occurrence is taken.
+char *strshift(char *s, int n);
+    ///< Shifts the given string to the left by the given number of bytes, thus
+    ///< removing the first n bytes from s.
+    ///< If n is greater than the length of s, the resulting string will be empty.
+    ///< If n is <= 0 s will be unchanged.
+    ///< Returns s.
 bool startswith(const char *s, const char *p);
 bool endswith(const char *s, const char *p);
 bool isempty(const char *s);
@@ -781,6 +787,12 @@ inline int CompareStringsIgnoreCase(const void *a, const void *b)
   return strcasecmp(*(const char **)a, *(const char **)b);
 }
 
+inline int CompareStringsNumerically(const void *a, const void *b)
+{
+  int d = atoi(*(const char **)a) - atoi(*(const char **)b);
+  return d ? d : CompareStrings(a, b);
+}
+
 class cStringList : public cVector<char *> {
 public:
   cStringList(int Allocated = 10): cVector<char *>(Allocated) {}
@@ -793,6 +805,10 @@ public:
     else
        cVector<char *>::Sort(CompareStrings);
   }
+  void SortNumerically(void)
+  {
+    cVector<char *>::Sort(CompareStringsNumerically);
+  }
   virtual void Clear(void);
   };