AIS:refine parsing of type 8 DAC 1 FID 16 messages

- Type 8, DAC = 1 FID = 16: This should only be decoded as "Persons on board" if the message length is either 72 or 136 bits long (if even then). - Type 8, DAC = 1 FID = 16: If decoded, the json output should use the ais->type8.dac1fid16.persons field and not the type6 field Was not able to locate entry that had persons actually populated in AISHub sample data file added sample data that should not be decoded to sample.aivdm had to regenerate large sample file as it had multiple entries for this Identified by: Stefan Roels <[email protected]> type 8 dac 1 fid 16 can have either data or persons had to add logic to detect structured vs not structured for type 8 FID 16 messages
andersson · Oct 8, 2015 · 780c8a9 · 780c8a9
1 parent 51916a1
commit 780c8a9
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Showing 7 changed files with 47 additions and 26 deletions.
diff --git a/ais_json.c b/ais_json.c
@@ -316,7 +316,9 @@ int json_ais_read(const char *buf,
 	    }
 	    else if (strstr(buf, "\"fid\":16,") != NULL) {
 		status = json_read_object(buf, json_ais8_fid16, endptr);
-		structured = true;
+		if (status == 0) {
+			structured = true;
+		}
 	    }
 	    else if (strstr(buf, "\"fid\":17,") != NULL) {
 		status = json_read_object(buf, json_ais8_fid17, endptr);

diff --git a/driver_ais.c b/driver_ais.c
@@ -526,10 +526,15 @@ bool ais_binary_decode(const struct gpsd_errout_t *errout,
 		break;
 	    case 16:	    /* Number of Persons On Board */
 		if (ais->type8.bitcount == 136)
-		    ais->type8.dac1fid16.persons = UBITS(88, 13);/* 289 */
-		else
-		    ais->type8.dac1fid16.persons = UBITS(55, 13);/* 236 */
-		ais->type8.structured = true;
+		{
+			ais->type8.dac1fid16.persons = UBITS(88, 13);/* 289 */
+			ais->type8.structured = true;
+		}
+		else if (ais->type8.bitcount == 72)
+		{
+			ais->type8.dac1fid16.persons = UBITS(55, 13);/* 236 */
+			ais->type8.structured = true;
+		}
 		break;
 	    case 17:        /* IMO289 - VTS-generated/synthetic targets */
 #define ARRAY_BASE 56

diff --git a/test/daemon/ais-nmea-sample.log.chk b/test/daemon/ais-nmea-sample.log.chk
diff --git a/test/sample.aivdm b/test/sample.aivdm
@@ -1065,3 +1065,11 @@ AIVDM,2,2,1,B,00000000000,2*26
 !AIVDM,3,2,7,A,?A;J6b7AwuiqIGLeNiKCPDR7HQR<u;TTFufegr>kCSF,0*41
 !AIVDM,3,3,7,A,Uq:1Kk`e8,4*27
 # {"class":"AIS","type":8,"repeat":0,"mmsi":366999607,"scaled":false,"dac":366,"fid":57,"data":"510:7ffdef068fbded3c0a1943dfb997b4a10fadec21e6e0a6608f0f44b686a8747ff71e595dcb5ec5b4e05221d886233d2e4916f6eb6fe8ecd38d69792816f3a2d0"}
+# sample of type 8 fid 16 where persons shouldn't be parsed
+!AIVDM,1,1,,A,802At?00D000qFap02:lA0b@?3fw0001<:iFP2:rf0cCGp0w00,4*5E
+#{"class":"AIS","type":8,"repeat":0,"mmsi":2391100,"scaled":false,"dac":1,"fid":16,"data":"240:0000e56a780022b4440a903c3bbf00000130ac568022bab80ad35f803f00"}
+# I do also have some examples of the type 8 DAC 1 FID 16 messages that should not be converted. I have no examples of the ones that should, but from the documentation, it seems not sure that they actually exist.
+!AIVDM,3,1,0,A,802UMp@0D002G`lCH2FuR@mE8;;w2d00001h82F0@hm;gh0w00010Wk3<2FG,0*00
+!AIVDM,3,2,0,A,ePm;5@0w0000iLBaP2F4khlwAH0w0000u7fUP2G=u0m3T@0w00010W:s02F>,0*72
+!AIVDM,3,3,0,A,Ghm4utWw2P,4*27
+# 8|0|002711009|1|16|720:00025e8d136025bd890d5520b2ff0ac000000070202580430d4bbf003f000001027cc3302597b60d4b15003f000000c5c4a9802584cf0d3f45803f000000f47ba58025cdf40d4391003f0000010272bb00258e5f0d44f7c9ff0a
diff --git a/test/sample.aivdm.chk b/test/sample.aivdm.chk
@@ -86,3 +86,5 @@
 8|0|002766080|1|11|1382800|3532000|20T18:30Z|0|0|0|0|0|0|0|0|0|0|0|0|255|0|0|0|0|0|0|0|0|3|0|0|0|0|0|1|0|0|0
 6|0|002053507|2|244670500|0|200|3|16:3200
 8|0|366999607|366|57|510:7ffdef068fbded3c0a1943dfb997b4a10fadec21e6e0a6608f0f44b686a8747ff71e595dcb5ec5b4e05221d886233d2e4916f6eb6fe8ecd38d69792816f3a2d0
+8|0|002391100|1|16|240:0000e56a780022b4440a903c3bbf00000130ac568022bab80ad35f803f00
+8|0|002711009|1|16|720:00025e8d136025bd890d5520b2ff0ac000000070202580430d4bbf003f000001027cc3302597b60d4b15003f000000c5c4a9802584cf0d3f45803f000000f47ba58025cdf40d4391003f0000010272bb00258e5f0d44f7c9ff0a
diff --git a/test/sample.aivdm.js.chk b/test/sample.aivdm.js.chk
@@ -86,3 +86,5 @@
 {"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2766080,"scaled":true,"dac":1,"fid":11,"lat":58.867,"lon":23.047,"timestamp":"20T18:30Z","wspeed":0,"wgust":0,"wdir":0,"wgustdir":0,"humidity":0,"airtemp":-60.0,"dewpoint":-20.0,"pressure":800,"pressuretend":"steady","visibility":0.0,"waterlevel":-10.0,"leveltrend":"steady","cspeed":25.5,"cdir":0,"cspeed2":0.0,"cdir2":0,"cdepth2":0,"cspeed3":0.0,"cdir3":0,"cdepth3":0,"waveheight":0.0,"waveperiod":3,"wavedir":0,"swellheight":0.0,"swellperiod":0,"swelldir":0,"seastate":0,"watertemp":-9.9,"preciptype":0,"preciptype_text":"reserved","salinity":0.0,"ice":0,"ice_text":"no"}
 {"class":"AIS","device":"stdin","type":6,"repeat":0,"mmsi":2053507,"scaled":true,"seqno":2,"dest_mmsi":244670500,"retransmit":false,"dac":200,"fid":3,"data":"16:3200"}
 {"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":366999607,"scaled":true,"dac":366,"fid":57,"data":"510:7ffdef068fbded3c0a1943dfb997b4a10fadec21e6e0a6608f0f44b686a8747ff71e595dcb5ec5b4e05221d886233d2e4916f6eb6fe8ecd38d69792816f3a2d0"}
+{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2391100,"scaled":true,"dac":1,"fid":16,"data":"240:0000e56a780022b4440a903c3bbf00000130ac568022bab80ad35f803f00"}
+{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2711009,"scaled":true,"dac":1,"fid":16,"data":"720:00025e8d136025bd890d5520b2ff0ac000000070202580430d4bbf003f000001027cc3302597b60d4b15003f000000c5c4a9802584cf0d3f45803f000000f47ba58025cdf40d4391003f0000010272bb00258e5f0d44f7c9ff0a"}
diff --git a/test/sample.aivdm.ju.chk b/test/sample.aivdm.ju.chk
@@ -86,3 +86,5 @@
 {"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2766080,"scaled":false,"dac":1,"fid":11,"lat":3532000,"lon":1382800,"timestamp":"20T18:30Z","wspeed":0,"wgust":0,"wdir":0,"wgustdir":0,"humidity":0,"airtemp":0,"dewpoint":0,"pressure":0,"pressuretend":0,"visibility":0,"waterlevel":0,"leveltrend":0,"cspeed":255,"cdir":0,"cspeed2":0,"cdir2":0,"cdepth2":0,"cspeed3":0,"cdir3":0,"cdepth3":0,"waveheight":0,"waveperiod":3,"wavedir":0,"swellheight":0,"swellperiod":0,"swelldir":0,"seastate":0,"watertemp":1,"preciptype":0,"preciptype_text":"reserved","salinity":0,"ice":0,"ice_text":"no"}
 {"class":"AIS","device":"stdin","type":6,"repeat":0,"mmsi":2053507,"scaled":false,"seqno":2,"dest_mmsi":244670500,"retransmit":false,"dac":200,"fid":3,"data":"16:3200"}
 {"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":366999607,"scaled":false,"dac":366,"fid":57,"data":"510:7ffdef068fbded3c0a1943dfb997b4a10fadec21e6e0a6608f0f44b686a8747ff71e595dcb5ec5b4e05221d886233d2e4916f6eb6fe8ecd38d69792816f3a2d0"}
+{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2391100,"scaled":false,"dac":1,"fid":16,"data":"240:0000e56a780022b4440a903c3bbf00000130ac568022bab80ad35f803f00"}
+{"class":"AIS","device":"stdin","type":8,"repeat":0,"mmsi":2711009,"scaled":false,"dac":1,"fid":16,"data":"720:00025e8d136025bd890d5520b2ff0ac000000070202580430d4bbf003f000001027cc3302597b60d4b15003f000000c5c4a9802584cf0d3f45803f000000f47ba58025cdf40d4391003f0000010272bb00258e5f0d44f7c9ff0a"}