drivers/apator: decode HCA proprietary payload

drivers/europe/apator/apator.c

@@ -8,6 +8,8 @@
 
 #include "../../engine/driver.h"
 
+#include <stdio.h>
+
 /* amiplus — smart electricity (relabelled by NES, DEV, APT). */
 static const WmbusMVT k_mvt_amiplus[] = {
     {"APA", 0x01, 0x02},
@@ -95,6 +97,63 @@ const WmbusDriver wmbus_drv_apator_elf = {
  * in the wild: wmbusmeters' apatoreitn driver registers (mfr, 0x08,
  * 0x04) which is version=0x08, medium=0x04, while older firmware uses
  * the inverted (0x04, 0x08). Cover both. */
+static uint16_t apator_hca_le16(const uint8_t* p) {
+    return (uint16_t)p[0] | ((uint16_t)p[1] << 8);
+}
+
+static size_t apator_hca_fallback(const uint8_t* a, size_t len, char* o, size_t cap) {
+    size_t pos = (size_t)snprintf(o, cap, "Apator HCA\n");
+    pos += (size_t)snprintf(o + pos, cap - pos,
+                            "Bytes %u\n"
+                            "Status bad length\n",
+                            (unsigned)len);
+
+    size_t off = 0;
+    int rows = 0;
+    while(off < len && rows < 3 && pos + 24 < cap) {
+        size_t n = len - off;
+        if(n > 6) n = 6;
+        pos += (size_t)snprintf(o + pos, cap - pos, "Hex%02u ", (unsigned)off);
+        for(size_t i = 0; i < n && pos + 3 < cap; i++) {
+            pos += (size_t)snprintf(o + pos, cap - pos, "%02X", a[off + i]);
+        }
+        if(pos + 1 < cap) {
+            o[pos++] = '\n';
+            o[pos] = '\0';
+        }
+        off += n;
+        rows++;
+    }
+
+    return pos;
+}
+
+static size_t decode_apator_hca(uint16_t m, uint8_t v, uint8_t med,
+                                const uint8_t* a, size_t len,
+                                char* o, size_t cap) {
+    (void)m;
+    (void)v;
+    (void)med;
+
+    if(len != 15) return apator_hca_fallback(a, len, o, cap);
+
+    const uint16_t units = apator_hca_le16(a + 3);
+    const uint16_t ref_units = apator_hca_le16(a + 7);
+
+    return (size_t)snprintf(o, cap,
+                            "Apator HCA\n"
+                            "Units %u\n"
+                            "RefUnits %u\n"
+                            "TempC %u\n"
+                            "Marker %02X%02X\n"
+                            "Flags %02X%02X%02X%02X%02X\n",
+                            units,
+                            ref_units,
+                            (unsigned)a[12],
+                            a[9], a[10],
+                            a[5], a[6], a[11], a[13], a[14]);
+}
+
 static const WmbusMVT k_mvt_apator_hca[] = {
     {"APA", 0x04, 0x08},
     {"APT", 0x04, 0x08},
@@ -104,7 +163,7 @@ static const WmbusMVT k_mvt_apator_hca[] = {
 };
 const WmbusDriver wmbus_drv_apator_hca = {
     .id = "apator-hca", .title = "Apator HCA",
-    .mvt = k_mvt_apator_hca, .decode = NULL,
+    .mvt = k_mvt_apator_hca, .decode = decode_apator_hca,
 };
 
 /* Ultrimis water (cold) */

tests/Makefile

@@ -20,6 +20,17 @@ IZAR_SRC = test_izar.c \
 test_izar: $(IZAR_SRC)
 	$(CC) $(CFLAGS) $(IZAR_SRC) -o $@
 
+APATOR_HCA_SRC = test_apator_hca.c \
+           ../drivers/europe/apator/apator.c \
+           ../drivers/engine/driver.c \
+           ../protocol/wmbus_link.c \
+           ../protocol/wmbus_manuf.c \
+           ../protocol/wmbus_medium.c \
+           ../protocol/wmbus_app_layer.c
+
+test_apator_hca: $(APATOR_HCA_SRC)
+	$(CC) $(CFLAGS) $(APATOR_HCA_SRC) -o $@
+
 PORTS_SRC = test_ports.c \
             ../drivers/europe/bmeters/hydrodigit.c \
             ../drivers/europe/engelmann/hydroclima.c \
@@ -36,12 +47,13 @@ PORTS_SRC = test_ports.c \
 test_ports: $(PORTS_SRC)
 	$(CC) $(CFLAGS) $(PORTS_SRC) -o $@
 
-check: test_link test_izar test_ports
+check: test_link test_izar test_apator_hca test_ports
 	./test_link
 	./test_izar
+	./test_apator_hca
 	./test_ports
 
 clean:
-	rm -f test_link test_izar test_ports
+	rm -f test_link test_izar test_apator_hca test_ports
 
 .PHONY: check clean

tests/test_apator_hca.c

@@ -0,0 +1,68 @@
+#include "../drivers/engine/driver.h"
+
+#include <stdio.h>
+#include <string.h>
+
+extern const WmbusDriver wmbus_drv_apator_hca;
+
+const WmbusDriver* const wmbus_engine_registry[] = { &wmbus_drv_apator_hca };
+const size_t wmbus_engine_registry_len = 1;
+
+#define MANUF(a, b, c) \
+    ((uint16_t)((((uint16_t)((a) - '@')) << 10) | \
+                (((uint16_t)((b) - '@')) << 5) | \
+                ((uint16_t)((c) - '@'))))
+
+static int expect_contains(const char* name, const char* out, const char* expected) {
+    if(strstr(out, expected)) return 0;
+    fprintf(stderr, "%s: missing '%s' in:\n%s\n", name, expected, out);
+    return 1;
+}
+
+static int run_sample(void) {
+    const uint8_t apdu[] = {
+        0x21, 0x01, 0x00, 0x87, 0x19, 0x00, 0x00, 0x04,
+        0x20, 0xE7, 0x34, 0x88, 0x16, 0x08, 0x19,
+    };
+    char out[256];
+    int fails = 0;
+
+    wmbus_engine_decode(MANUF('A', 'P', 'A'), 0x04, 0x08,
+                        apdu, sizeof(apdu), out, sizeof(out));
+
+    fails += expect_contains("sample", out, "Apator HCA\n");
+    fails += expect_contains("sample", out, "Units 6535\n");
+    fails += expect_contains("sample", out, "RefUnits 8196\n");
+    fails += expect_contains("sample", out, "TempC 22\n");
+    fails += expect_contains("sample", out, "Marker E734\n");
+    fails += expect_contains("sample", out, "Flags 0000880819\n");
+
+    return fails;
+}
+
+static int run_bad_length(void) {
+    const uint8_t apdu[] = {0x21, 0x01, 0x00};
+    char out[256];
+    int fails = 0;
+
+    wmbus_engine_decode(MANUF('A', 'P', 'A'), 0x04, 0x08,
+                        apdu, sizeof(apdu), out, sizeof(out));
+
+    fails += expect_contains("bad_length", out, "Apator HCA\n");
+    fails += expect_contains("bad_length", out, "Bytes 3\n");
+    fails += expect_contains("bad_length", out, "Status bad length\n");
+    fails += expect_contains("bad_length", out, "Hex00 210100\n");
+
+    return fails;
+}
+
+int main(void) {
+    int fails = 0;
+
+    fails += run_sample();
+    fails += run_bad_length();
+
+    if(fails) return 1;
+    printf("All Apator HCA tests passed.\n");
+    return 0;
+}