Version 1.09.1607.14

Improvements to COAA MLAT functions
Reduce CPU load in PPUP1090 and DUMP1090 during cleanup

dump1090.h

@@ -37,7 +37,7 @@
 // MinorVer changes when additional features are added, but not for bug fixes (range 00-99)
 // DayDate & Year changes for all changes, including for bug fixes. It represent the release date of the update
 //
-#define MODES_DUMP1090_VERSION     "1.09.1007.14"
+#define MODES_DUMP1090_VERSION     "1.09.1607.14"
 
 // ============================= Include files ==========================
 
@@ -229,6 +229,7 @@ struct aircraft {
 
 struct stDF {
     struct stDF     *pNext;                      // Pointer to next item in the linked list
+    struct stDF     *pPrev;                      // Pointer to previous item in the linked list
     struct aircraft *pAircraft;                  // Pointer to the Aircraft structure for this DF
     time_t           seen;                       // Dos/UNIX Time at which the this packet was received
     uint64_t         llTimestamp;                // Timestamp at which the this packet was received
@@ -325,6 +326,7 @@ struct {                             // Internal state
     // Interactive mode
     struct aircraft *aircrafts;
     uint64_t         interactive_last_update; // Last screen update in milliseconds
+    time_t           last_cleanup_time;       // Last cleanup time in seconds
 
     // DF List mode
     int             bEnableDFLogging; // Set to enable DF Logging

interactive.c

@@ -61,8 +61,10 @@ void interactiveCreateDF(struct aircraft *a, struct modesMessage *mm) {
         memcpy(pDF->msg, mm->msg, MODES_LONG_MSG_BYTES);
 
         if (!pthread_mutex_lock(&Modes.pDF_mutex)) {
-            pDF->pNext = Modes.pDF;
-            Modes.pDF  = pDF;
+            if ((pDF->pNext = Modes.pDF)) {
+                Modes.pDF->pPrev = pDF;
+            }
+            Modes.pDF = pDF;
             pthread_mutex_unlock(&Modes.pDF_mutex);
         } else {
             free(pDF);
@@ -83,7 +85,7 @@ void interactiveRemoveStaleDF(time_t now) {
         pDF  = Modes.pDF;
         while(pDF) {
             if ((now - pDF->seen) > Modes.interactive_delete_ttl) {
-                if (!prev) {
+                if (Modes.pDF == pDF) {
                     Modes.pDF = NULL;
                 } else {
                     prev->pNext = NULL;
@@ -91,14 +93,13 @@ void interactiveRemoveStaleDF(time_t now) {
 
                 // All DF's in the list from here onwards will be time
                 // expired, so delete them all
-                while ((prev = pDF)) {
-                    pDF = pDF->pNext;
+                while (pDF) {
+                    prev = pDF; pDF = pDF->pNext;
                     free(prev);
                 }
 
             } else {
-                prev = pDF;
-                pDF  = pDF->pNext;
+                prev = pDF; pDF = pDF->pNext;
             }
         }
         pthread_mutex_unlock (&Modes.pDF_mutex);
@@ -533,25 +534,24 @@ void interactiveRemoveStaleAircrafts(void) {
     struct aircraft *prev = NULL;
     time_t now = time(NULL);
 
-    interactiveRemoveStaleDF(now);
+    // Only do cleanup once per second
+    if (Modes.last_cleanup_time != now) {
+        Modes.last_cleanup_time = now;
 
-    while(a) {
-        if ((now - a->seen) > Modes.interactive_delete_ttl) {
-            struct aircraft *next = a->next;
-            // Remove the element from the linked list, with care
-            // if we are removing the first element
+        interactiveRemoveStaleDF(now);
 
-            if (!prev) {
-                Modes.aircrafts = next;
+        while(a) {
+            if ((now - a->seen) > Modes.interactive_delete_ttl) {
+                // Remove the element from the linked list, with care
+                // if we are removing the first element
+                if (!prev) {
+                    Modes.aircrafts = a->next; free(a); a = Modes.aircrafts;
+                } else {
+                    prev->next = a->next; free(a); a = prev->next;
+                }
             } else {
-                prev->next = next;
+                prev = a; a = a->next;
             }
-             
-            free(a);
-            a = next;
-        } else {
-            prev = a;
-            a = a->next;
         }
     }
 }

mode_s.c

@@ -2044,7 +2044,6 @@ void decodeCPR(struct aircraft *a, int fflag, int surface) {
             surface_rlat = Modes.fUserLat;
             surface_rlon = Modes.fUserLon;
         } else {
-            surface_rlat = Modes.fUserLat;
             return;
         }
         rlat0 += floor(surface_rlat / 90.0) * 90.0;  // Move from 1st quadrant to our quadrant

ppup1090.c

@@ -208,7 +208,7 @@ int main(int argc, char **argv) {
 
 #ifdef _WIN32
     // Try to comply with the Copyright license conditions for binary distribution
-    if (!Modes.quiet) {showCopyright();}
+    if (!ppup1090.quiet) {showCopyright();}
 #endif
 
     // Initialization
@@ -222,18 +222,18 @@ int main(int argc, char **argv) {
     //
     // Setup a service callback client structure for a beast binary input (from dump1090)
     // This is a bit dodgy under Windows. The fd parameter is a handle to the internet
-    // socket on which we are receiving data. Under Linux, these seem to start at 0 and 
+    // socket on which we are receiving data. Under Linux, these seem to start at 0 and
     // count upwards. However, Windows uses "HANDLES" and these don't nececeriy start at 0.
-    // dump1090 limits fd to values less than 1024, and then uses the fd parameter to 
+    // dump1090 limits fd to values less than 1024, and then uses the fd parameter to
     // index into an array of clients. This is ok-ish if handles are allocated up from 0.
-    // However, there is no gaurantee that Windows will behave like this, and if Windows 
-    // allocates a handle greater than 1024, then dump1090 won't like it. On my test machine, 
+    // However, there is no gaurantee that Windows will behave like this, and if Windows
+    // allocates a handle greater than 1024, then dump1090 won't like it. On my test machine,
     // the first Windows handle is usually in the 0x54 (84 decimal) region.
 
     c = (struct client *) malloc(sizeof(*c));
     c->next    = NULL;
     c->buflen  = 0;
-    c->fd      = 
+    c->fd      =
     c->service =
     Modes.bis  = fd;
     Modes.clients = c;
@@ -246,7 +246,7 @@ int main(int argc, char **argv) {
     }
 
     // The user has stopped us, so close any socket we opened
-    if (fd != ANET_ERR) 
+    if (fd != ANET_ERR)
       {close(fd);}
 
     closeCOAA ();