Check in AIVDM regression tests for sentence types 1-4.

6 files changed, 320 insertions, 28 deletions

diff --git a/Makefile.am b/Makefile.am
index efd89229..4ae29d71 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -438,6 +438,25 @@ rtcm-makeregress: gpsdecode
 		$(srcdir)/gpsdecode < $${f} > $${f}.chk; \
 	done
 
+
+# Regression-test the AIVDM decoder.
+aivdm-regress: gpsdecode
+	@echo "Testing AIVDM decoding..."
+	@mkdir -p test
+	@for f in $(srcdir)/test/*.aivdm; do \
+		echo "Testing $${f}..."; \
+		$(srcdir)/gpsdecode <$${f} >test/test.chk; \
+		diff -ub $${f}.chk test/test.chk; \
+	done; \
+	rm test/test.chk
+
+# Rebuild the AIVDM regression tests.
+aivdm-makeregress: gpsdecode
+	@for f in $(srcdir)/test/*.aivdm; do \
+		$(srcdir)/gpsdecode < $${f} > $${f}.chk; \
+	done
+
+
 # Regression-test the packet getter.
 packet-regress: test_packet
 	@echo "Testing detection of invalid packets..."
@@ -471,7 +490,7 @@ time_regress: test_mkgmtime
 	./test_mkgmtime
 
 # Do all normal regression tests
-testregress: gps-regress rtcm-regress packet-regress undump-regress time_regress
+testregress: gps-regress rtcm-regress aidvm-regress packet-regress undump-regress time_regress
 	@echo "Regressions complete."
 
 # We would like "${MAKE} check" to run the regression tests.  automake
diff --git a/bits.c b/bits.c
index 41599634..bd807348 100644
--- a/bits.c
+++ b/bits.c
@@ -30,25 +30,30 @@ unsigned long long ubits(char buf[], unsigned int start, unsigned int width)
 	fld <<= BITS_PER_BYTE;
 	fld |= (unsigned char)buf[i];
     }
-#ifdef UDEBUG
-    printf("Extracting %d:%d from %s: segment 0x%llx = %lld\n", start, width,
-	   gpsd_hexdump(buf, 12), fld, fld);
-#endif /* UDEBUG */
+#ifdef DEBUG
+    (void)printf("%d:%d from %s:\n", start, width, gpsd_hexdump(buf, 32));
+#endif 
 
+#ifdef DEBUG
+    (void)printf("    segment=0x%llx,", fld);
+#endif /* DEBUG */
     end = (start + width) % BITS_PER_BYTE;
     if (end != 0) {
 	fld >>= (BITS_PER_BYTE - end);
-#ifdef UDEBUG
-	printf("After downshifting by %d bits: 0x%llx = %lld\n", 
-	       BITS_PER_BYTE - end, fld, fld);
+#ifdef DEBUG
+	(void)printf(" after downshifting by %d bits: 0x%llx", 
+		     BITS_PER_BYTE - end, fld);
 #endif /* UDEBUG */
     }
+#ifdef DEBUG
+    (void)printf(" = %lld\n", fld);
+#endif /* UDEBUG */
 
     fld &= ~(-1LL << width);
-#ifdef UDEBUG
-    printf("After selecting out the bottom %u bits: 0x%llx = %lld\n", 
-	   width, fld, fld);
-#endif /* UDEBUG */
+#ifdef DEBUG
+    (void)printf("    after selecting out the bottom %u bits: 0x%llx = %lld\n", 
+		 width, fld, fld);
+#endif /* DEBUG */
 
     return fld;
 }
@@ -58,19 +63,19 @@ signed long long sbits(char buf[], unsigned int start, unsigned int width)
 {
     unsigned long long fld = ubits(buf, start, width);
 
-#ifdef DEBUG
+#ifdef SDEBUG
     (void)fprintf(stderr, "sbits(%d, %d) extracts %llx\n", start, width, fld);
-#endif /* DEBUG */
+#endif /* SDEBUG */
     /*@ +relaxtypes */
     if (fld & (1 << (width-1))) {
-#ifdef DEBUG
+#ifdef SDEBUG
 	(void)fprintf(stderr, "%llx is signed\n", fld);
-#endif /* DEBUG */
+#endif /* SDEBUG */
 	fld |= (-1LL << (width-1));
     }
-#ifdef DEBUG
+#ifdef SDEBUG
     (void)fprintf(stderr, "sbits(%d, %d) returns %lld\n", start, width, (signed long long)fld);
-#endif /* DEBUG */
+#endif /* SDEBUG */
     return (signed long long)fld;
     /*@ -relaxtypes */
 }
diff --git a/packet.c b/packet.c
index e5645cb0..3f3641c5 100644
--- a/packet.c
+++ b/packet.c
@@ -968,8 +968,10 @@ void packet_parse(struct gps_packet_t *lexer)
 		else
 #endif /* AIVDM_ENABLE */
 		    packet_accept(lexer, NMEA_PACKET);
-	    } else
+	    } else {
+		gpsd_report(LOG_WARN, "bad checksum in NMEA packet.\n");
 		lexer->state = GROUND_STATE;
+	    }
 	    packet_discard(lexer);
 	    break;
 	}
diff --git a/test/schwehr.aivdm b/test/schwehr.aivdm
new file mode 100644
index 00000000..1ed0c9a2
--- /dev/null
+++ b/test/schwehr.aivdm
@@ -0,0 +1,125 @@
+# Sample AIVDM data sentences provided from real data by Kurt Schwehr
+#
+# Sample sentences of types 1-4.
+#
+!AIVDM,1,1,,A,15RTgt0PAso;90TKcjM8h6g208CQ,0*4A
+#       MessageID:          1
+#       RepeatIndicator:    0
+#       UserID:             371798000
+#       NavigationStatus:   0
+#       ROT:                -127
+#       SOG:                12.3
+#       PositionAccuracy:   1
+#       longitude:          -123.395383333
+#       latitude:           48.38163333333
+#       COG:                224
+#       TrueHeading:        215
+#       TimeStamp:          33
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slotoffset:   4252
+#
+!AIVDM,1,1,,A,16SteH0P00Jt63hHaa6SagvJ087r,0*42
+#       MessageID:          1
+#       RepeatIndicator:    0
+#       UserID:             440348000
+#       NavigationStatus:   0
+#       ROT:                -128
+#       SOG:                0
+#       PositionAccuracy:   0
+#       longitude:          -70.7582
+#       latitude:           43.08015
+#       COG:                93.4
+#       TrueHeading:        511
+#       TimeStamp:          13
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       stare_slottimeout:  2
+#       state_slotoffset:   506
+#
+# 2 is really uncommon
+#
+!AIVDM,1,1,,B,25Cjtd0Oj;Jp7ilG7=UkKBoB0<06,0*60
+#       MessageID:          2
+#       RepeatIndicator:    0
+#       UserID:             356302000
+#       NavigationStatus:   0
+#       ROT:                127
+#       SOG:                13.9
+#       PositionAccuracy:   0
+#       longitude:          -71.62614333333333333333333333
+#       latitude:           40.39235833333333333333333333
+#       COG:                87.7
+#       TrueHeading:        91
+#       TimeStamp:          41
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  3
+#       state_slotoffset:   6
+#
+!AIVDM,1,1,,A,38Id705000rRVJhE7cl9n;160000,0*40
+#       MessageID:          3
+#       RepeatIndicator:    0
+#       UserID:             563808000
+#       NavigationStatus:   5
+#       ROT:                0
+#       SOG:                0
+#       PositionAccuracy:   1
+#       longitude:          -76.32753333333333333333333333
+#       latitude:           36.91
+#       COG:                252
+#       TrueHeading:        352
+#       TimeStamp:          35
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  0
+#       state_slotoffset:   0
+#
+!AIVDM,1,1,,A,403OviQuMGCqWrRO9>E6fE700@GO,0*4D
+#       MessageID:          4
+#       RepeatIndicator:    0
+#       UserID:             3669702
+#       Time_year:          2007
+#       Time_month:         5
+#       Time_day:           14
+#       Time_hour:          19
+#       Time_min:           57
+#       Time_sec:           39
+#       PositionAccuracy:   1
+#       Position_longitude: -76.35236166666666666666666667
+#       Position_latitude:  36.88376666666666666666666667
+#       fixtype:            7
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  4
+#       state_slotoffset:   1503
+#
+!AIVDM,1,1,,A,403OviQuMGCqWrRO9>E6fE700@GO,0*4D
+#       MessageID:           4
+#       RepeatIndicator:     0
+#       UserID:              3669702
+#       Time_year:           2007
+#       Time_month:          5
+#       Time_day:            14
+#       Time_hour:           19
+#       Time_min:            57
+#       Time_sec:            39
+#       PositionAccuracy:    1
+#       Position_longitude:  -76.35236166666666666666666667
+#       Position_latitude:   36.88376666666666666666666667
+#       fixtype:             7
+#       Spare:               0
+#       RAIM:                False
+#       state_syncstate:     0
+#       state_slottimeout:   4
+#       state_slotoffset:    1503
+#
diff --git a/test/schwehr.aivdm.chk b/test/schwehr.aivdm.chk
new file mode 100644
index 00000000..f3d22f7f
--- /dev/null
+++ b/test/schwehr.aivdm.chk
@@ -0,0 +1,118 @@
+# Sample AIVDM data sentences provided from real data by Kurt Schwehr
+#
+# Sample sentences of types 1-4.
+#
+1,0,371798000,Under way using engine,fastleft,12.3,1,-123.3954,48.3816,2240,215,33,0,0,84e1
+#       RepeatIndicator:    0
+#       UserID:             371798000
+#       NavigationStatus:   0
+#       ROT:                -127
+#       SOG:                12.3
+#       PositionAccuracy:   1
+#       longitude:          -123.395383333
+#       latitude:           48.38163333333
+#       COG:                224
+#       TrueHeading:        215
+#       TimeStamp:          33
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slotoffset:   4252
+#
+1,0,440348000,Under way using engine,nan,0.0,0,-70.7582,43.0802,934,511,13,0,0,81fa
+#       RepeatIndicator:    0
+#       UserID:             440348000
+#       NavigationStatus:   0
+#       ROT:                -128
+#       SOG:                0
+#       PositionAccuracy:   0
+#       longitude:          -70.7582
+#       latitude:           43.08015
+#       COG:                93.4
+#       TrueHeading:        511
+#       TimeStamp:          13
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       stare_slottimeout:  2
+#       state_slotoffset:   506
+#
+# 2 is really uncommon
+#
+2,0,356302000,Under way using engine,fastright,13.9,0,-71.6261,40.3924,877,91,41,0,0,c006
+#       RepeatIndicator:    0
+#       UserID:             356302000
+#       NavigationStatus:   0
+#       ROT:                127
+#       SOG:                13.9
+#       PositionAccuracy:   0
+#       longitude:          -71.62614333333333333333333333
+#       latitude:           40.39235833333333333333333333
+#       COG:                87.7
+#       TrueHeading:        91
+#       TimeStamp:          41
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  3
+#       state_slotoffset:   6
+#
+3,1,563808000,Moored,0,0.0,1,-76.3275,36.9100,2520,352,35,0,0,0
+#       RepeatIndicator:    0
+#       UserID:             563808000
+#       NavigationStatus:   5
+#       ROT:                0
+#       SOG:                0
+#       PositionAccuracy:   1
+#       longitude:          -76.32753333333333333333333333
+#       latitude:           36.91
+#       COG:                252
+#       TrueHeading:        352
+#       TimeStamp:          35
+#       RegionalReserved:   0
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  0
+#       state_slotoffset:   0
+#
+4,0,003669702,2007:05:14T19:57:39Z,1,36.8838,-76.3524,Surveyed,0,82ef
+#       RepeatIndicator:    0
+#       UserID:             3669702
+#       Time_year:          2007
+#       Time_month:         5
+#       Time_day:           14
+#       Time_hour:          19
+#       Time_min:           57
+#       Time_sec:           39
+#       PositionAccuracy:   1
+#       Position_longitude: -76.35236166666666666666666667
+#       Position_latitude:  36.88376666666666666666666667
+#       fixtype:            7
+#       Spare:              0
+#       RAIM:               False
+#       state_syncstate:    0
+#       state_slottimeout:  4
+#       state_slotoffset:   1503
+#
+#       RepeatIndicator:     0
+#       UserID:              3669702
+#       Time_year:           2007
+#       Time_month:          5
+#       Time_day:            14
+#       Time_hour:           19
+#       Time_min:            57
+#       Time_sec:            39
+#       PositionAccuracy:    1
+#       Position_longitude:  -76.35236166666666666666666667
+#       Position_latitude:   36.88376666666666666666666667
+#       fixtype:             7
+#       Spare:               0
+#       RAIM:                False
+#       state_syncstate:     0
+#       state_slottimeout:   4
+#       state_slotoffset:    1503
+#
diff --git a/www/AIVDM.txt b/www/AIVDM.txt
index 9f7b891e..76a9c620 100644
--- a/www/AIVDM.txt
+++ b/www/AIVDM.txt
@@ -30,23 +30,29 @@ found at <<AIS>>.
 
 == Standards ==
 
-The relevant standard is ITU Recommendation M.1371, "Technical
-Characteristics for a Universal Shipborne Automatic. Identification
-System Using Time Division Multiple Access" <<ITU1371>>, issued in 2001. It is
-proprietary, expensive, and surrounded by attack lawyers, which is why
-this document exists.  I have not looked at it.
+ITU Recommendation M.1371, "Technical Characteristics for a Universal
+Shipborne Automatic. Identification System Using Time Division
+Multiple Access" <<ITU1371>>, issued in 2001, describes the format of
+AIS binary messages. It is proprietary, expensive, and surrounded by
+attack lawyers, which is why this document exists.  I have not looked
+at it.
 
 ITU-R M.1371 is expanded and clarified by "IALA Technical
 Clarifications on Recommendation ITU-R M.1371-1" <<IALA>>, which
 is freely available.
 
+I have been unable to determine what technical standard sets the ASCII
+format for AIS messages; most likely it is <<NMEA>>, which I also have
+not looked at because it is proprietary and expensive and surrounded
+by even more rapacious attack lawyers.
+
 == Information Sources ==
 
 Together, the the IALA Technical Clarifications at <<IALA>> and the
 Coast Guard's AIS pages at <<NAVCEN>> describe AIS message payloads
 almost completely.  The detail information on payload formats in this
 document is derived from these.  Together, they explain everything
-except the Repeat Indicator found in some messages
+except the Repeat Indicator found in some messages.
 
 The AIVDM ASCII packet format is described at <<BOSUN>>.
 
@@ -56,7 +62,7 @@ There's a web form that does sentence decoding at http://rl.se/aivdm.
 
 AIVDM/AIVDO is a two-layer protocol.  The outer layer is a variant of
 NMEA 0183, the ancient standard for data interchange in marine
-navigation systems, described at <<NMEA>>.
+navigation systems; NMEA 0183 is described at <<NMEA>>.
 
 Here is a typical AIVDM data packet:
 
@@ -180,7 +186,7 @@ software.
 Field   Len Description                       Units
 -------------------------------------------------------------------------------
 0-5      6  Message Type             Unsigned integer: 1-24
-6-7      2  Repeat Indicator         Unknown
+6-7      2  Repeat Indicator         Unknown; 3 = "Do not repeat".
 8-37    30  MMSI                     Unsigned integer: 9 decimal digits
 38-41    4  Navigation Status        See table below
 42-49    8  Rate of Turn (ROT)       Signed integer: see below
@@ -242,7 +248,7 @@ default.
 
 Latitude is given in in 1/10000 min. Values up to plus or minus 90
 degrees, North = positive, South = negative. A value of 91 degrees (0x3412140
-hex) indicates latitude is not available (default).
+hex) indicates latitude is not available and is the default.
 
 Seconds in UTC timestamp should be 0-59, except for these special values:
 
@@ -418,6 +424,20 @@ Code   Ship & Cargo Classification
 99     Other Type, no additional information
 -------------------------------------------------------------
 
+== Local extensions ==
+
+Some regional authorities extend the AIS message set.
+
+The St. Lawrence Seaway broadcasts hydrological and lock-scheduling
+messages using special encodings of the binary data of message types 6
+and 8 (described in <<SEAWAY>>, freely available), and safety
+information using types 12 and 14.
+
+The U.S. Coast Guard has a system called PAWSS (Port and Water Safety
+System) which uses extended AIS formats. <<SEAWAY>> says it's
+intercompatible with the St. Lawrence Seaway system; I have not
+been able to find any message documentation, however.
+
 == References ==
 
 [bibliography]
@@ -439,3 +459,6 @@ Identification System]
 - [[[BOSUN]]] http://www.bosunsmate.org/ais/[Marine Automatic Identification System (AIS)]
 
 - [[[NMEA]]] http://gpsd.berlios.de/standards/NMEA.txt[NMEA sentences]
+
+- [[[SEAWAY]]] http://www.greatlakes-seaway.com/en/pdf/aisdata.pdf[St. Lawrence
+  Seaway AIS Data Messaging Formats and Specifications]