Shearwater: restore ID_MODEL as model source, expose FWID for consumer sub-model refinement

include/libdivecomputer/descriptor.h

@@ -124,6 +124,26 @@ dc_descriptor_get_transports (const dc_descriptor_t *descriptor);
 int
 dc_descriptor_filter (const dc_descriptor_t *descriptor, dc_transport_t transport, const void *userdata);
 
+/**
+ * Find a descriptor by hardware identifier.
+ *
+ * Some device families share a coarse model number across multiple marketed
+ * products. When a device reports a hardware identifier (via
+ * DC_EVENT_DEVINFO.hw_id), this function can find a more specific
+ * descriptor than the model number alone provides. This is best-effort:
+ * returns NULL if the hardware id is unknown or not in the table.
+ *
+ * The returned descriptor is a direct reference to an internal table entry
+ * and must be released with dc_descriptor_free(), which is safe to call on
+ * such a reference.
+ *
+ * @param[in]  family  The device family type.
+ * @param[in]  hw_id   The hardware identifier from DC_EVENT_DEVINFO.
+ * @returns A descriptor on success, or NULL if no match.
+ */
+dc_descriptor_t *
+dc_descriptor_find_by_hw_id (dc_family_t family, unsigned int hw_id);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

include/libdivecomputer/device.h

@@ -52,6 +52,13 @@ typedef struct dc_event_devinfo_t {
 	unsigned int model;
 	unsigned int firmware;
 	unsigned int serial;
+	/* Generic hardware identifier, 0 = unknown/not available.
+	 * On live download from devices that support it, this is populated
+	 * with the device's hardware type identifier (e.g. Shearwater FWID
+	 * from RDBI 0x8050). It supplements the coarse model field for
+	 * consumer-side sub-model differentiation. Consumers that do not use
+	 * this field are unaffected; the model field remains authoritative. */
+	unsigned int hw_id;
 } dc_event_devinfo_t;
 
 typedef struct dc_event_clock_t {

src/cochran_commander.c

@@ -937,7 +937,6 @@ cochran_commander_device_foreach (dc_device_t *abstract, dc_dive_callback_t call
 		devinfo.serial = array_uint32_word_be(data.config + layout->cf_serial_number);
 	else
 		devinfo.serial = array_uint32_le(data.config + layout->cf_serial_number);
-
 	device_event_emit (abstract, DC_EVENT_DEVINFO, &devinfo);
 
 	unsigned int head_dive = 0, tail_dive = 0, dive_count = 0;

src/descriptor.c

@@ -97,6 +97,38 @@ static const dc_iterator_vtable_t dc_descriptor_iterator_vtable = {
  * actually used to identify individual models, identical values are assigned.
  */
 
+/* Hardware-identifier to descriptor mapping.
+ *
+ * Some device families share a coarse model number (DC_EVENT_DEVINFO.model)
+ * across multiple marketed products; the hardware identifier (hw_id)
+ * from DC_EVENT_DEVINFO can refine the selection to a specific descriptor.
+ * This table is best-effort: the FWID is only available on live download and
+ * may change across firmware updates. Consumers should treat a NULL result
+ * from dc_descriptor_find_by_hw_id() as "use the coarse model descriptor". */
+typedef struct {
+	dc_family_t family;
+	unsigned int model;
+	unsigned int hw_id;
+	const char *product;
+} dc_hw_id_entry_t;
+
+static const dc_hw_id_entry_t g_hw_id_map[] = {
+	/* Shearwater Petrel family.
+	 * Petrel 1 (model=3): hardware ids 0x0404, 0x0909 */
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0404, "Petrel"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0909, "Petrel"},
+	/* Petrel 2 (model=3): hardware ids 0x0505, 0x0808, 0x0838, 0x08A5,
+	 *                                   0x0B0B, 0x7828, 0x7B2C, 0x8838 */
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0505, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0808, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0838, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x08A5, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x0B0B, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x7828, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x7B2C, "Petrel 2"},
+	{DC_FAMILY_SHEARWATER_PETREL, 3, 0x8838, "Petrel 2"},
+};
+
 static const dc_descriptor_t g_descriptors[] = {
 	/* Suunto Solution */
 	{"Suunto", "Solution", DC_FAMILY_SUUNTO_SOLUTION, 0, DC_TRANSPORT_SERIAL, NULL},
@@ -1055,6 +1087,36 @@ dc_descriptor_free (dc_descriptor_t *descriptor)
 	return;
 }
 
+dc_descriptor_t *
+dc_descriptor_find_by_hw_id (dc_family_t family, unsigned int hw_id)
+{
+	if (hw_id == 0)
+		return NULL;
+
+	for (size_t i = 0; i < C_ARRAY_SIZE(g_hw_id_map); i++) {
+		if (g_hw_id_map[i].family != family || g_hw_id_map[i].hw_id != hw_id)
+			continue;
+
+		/* Matched — find the corresponding entry in g_descriptors[] by
+		 * family, model, and product name.  Returning a direct pointer
+		 * into the static table is safe: dc_descriptor_free() is a
+		 * no-op and g_descriptors[] has static storage duration. */
+		for (size_t j = 0; j < C_ARRAY_SIZE(g_descriptors); j++) {
+			if (g_descriptors[j].type == family &&
+			    g_descriptors[j].model == g_hw_id_map[i].model &&
+			    strcmp(g_descriptors[j].product, g_hw_id_map[i].product) == 0) {
+				return (dc_descriptor_t *) &g_descriptors[j];
+			}
+		}
+		/* hw_id matched the map but the descriptor was not found —
+		 * product name mismatch or g_descriptors[] was edited without
+		 * updating g_hw_id_map[]. */
+		return NULL;
+	}
+
+	return NULL;
+}
+
 const char *
 dc_descriptor_get_vendor (const dc_descriptor_t *descriptor)
 {

src/device-private.h

@@ -88,6 +88,9 @@ dc_device_deallocate (dc_device_t *device);
 void
 device_event_emit (dc_device_t *device, dc_event_type_t event, const void *data);
 
+void
+device_set_hw_id (dc_device_t *device, unsigned int hw_id);
+
 int
 device_is_cancelled (dc_device_t *device);
 

src/device.c

@@ -462,6 +462,13 @@ dc_device_close (dc_device_t *device)
 }
 
 
+// AI-generated (Claude)
+void
+device_set_hw_id (dc_device_t *device, unsigned int hw_id)
+{
+	device->devinfo.hw_id = hw_id;
+}
+
 void
 device_event_emit (dc_device_t *device, dc_event_type_t event, const void *data)
 {
@@ -493,7 +500,13 @@ device_event_emit (dc_device_t *device, dc_event_type_t event, const void *data)
 	// Cache the event data.
 	switch (event) {
 	case DC_EVENT_DEVINFO:
-		device->devinfo = *(const dc_event_devinfo_t *) data;
+	{
+		const dc_event_devinfo_t *devinfo = (const dc_event_devinfo_t *) data;
+		device->devinfo.model = devinfo->model;
+		device->devinfo.firmware = devinfo->firmware;
+		device->devinfo.serial = devinfo->serial;
+		data = &device->devinfo;
+	}
 		break;
 	case DC_EVENT_CLOCK:
 		device->clock = *(const dc_event_clock_t *) data;

src/libdivecomputer.symbols

@@ -36,6 +36,7 @@ dc_descriptor_get_type
 dc_descriptor_get_model
 dc_descriptor_get_transports
 dc_descriptor_filter
+dc_descriptor_find_by_hw_id
 
 dc_iostream_get_transport
 dc_iostream_set_timeout

src/shearwater_common.c

@@ -762,110 +762,3 @@ shearwater_common_timesync_utc (shearwater_common_device_t *device, const dc_dat
 
 	return status;
 }
-
-dc_status_t shearwater_common_get_model(shearwater_common_device_t *device, unsigned int *model)
-{
-	// Read the hardware type.
-	unsigned char rsp_hardware[2] = {0};
-	dc_status_t status = shearwater_common_rdbi (device, ID_HARDWARE, rsp_hardware, sizeof(rsp_hardware), NULL);
-	if (status != DC_STATUS_SUCCESS) {
-		ERROR (device->base.context, "Failed to read the hardware type.");
-		return status;
-	}
-
-	// Convert and map to the model number.
-	unsigned int hardware = array_uint16_be (rsp_hardware);
-
-	DEBUG(device->base.context, "Hardware type: 0x%04x", hardware);
-
-	switch (hardware) {
-	case 0x0101:
-	case 0x0202:
-		*model = PREDATOR;
-		break;
-	case 0x0404:
-	case 0x0909:
-		*model = PETREL;
-		break;
-	case 0x0505:
-	case 0x0808:
-	case 0x0838:
-	case 0x08A5:
-	case 0x0B0B:
-	case 0x7828:
-	case 0x7B2C:
-	case 0x8838:
-		*model = PETREL2;
-		break;
-	case 0xB407:
-	case 0xB429:
-	case 0xB469:
-	case 0x3C3D:
-		*model = PETREL3;
-		break;
-	case 0x0606:
-	case 0x0A0A:
-		*model = NERD;
-		break;
-	case 0x0E0D:
-	case 0x7E2D:
-		*model = NERD2;
-		break;
-	case 0x0707:
-		*model = PERDIX;
-		break;
-	case 0x0C0D:
-	case 0x425B:
-	case 0x7C2D:
-	case 0x8D6C:
-		*model = PERDIXAI;
-		break;
-	case 0x704C:
-	case 0x924C:
-	case 0x9C64:
-	case 0xC407:
-	case 0xC429:
-	case 0xC964:
-		*model = PERDIX2;
-		break;
-	case 0x39C2:
-	case 0x4AB1:
-		*model = PERDIX3;
-		break;
-	case 0x1F0A:
-	case 0x1F0F:
-	case 0x0F0F:
-	case 0x1F10:
-	case 0x1F1A:
-		*model = TERIC;
-		break;
-	case 0x1512:
-	case 0x1613:
-	case 0x2623:
-	case 0x63A5:
-		*model = PEREGRINE;
-		break;
-	case 0x1712:
-	case 0x813A:
-		*model = PEREGRINE_TX;
-		break;
-	case 0xC0E0:
-		*model = TERN;
-		break;
-	default:
-		// Unknown hardware type: fall back to reading the model number directly from the device.
-		WARNING (device->base.context, "Unknown hardware type 0x%04x, falling back to ID_MODEL.", hardware);
-		{
-			unsigned char rsp_model = 0;
-			dc_status_t rc = shearwater_common_rdbi (device, ID_MODEL, &rsp_model, sizeof(rsp_model), NULL);
-			if (rc != DC_STATUS_SUCCESS) {
-				ERROR (device->base.context, "Failed to read the model number.");
-				return rc;
-			}
-			*model = rsp_model;
-		}
-		break;
-	}
-
-	return status;
-}

src/shearwater_common.h

@@ -46,6 +46,9 @@ extern "C" {
 
 #define PREDATOR 2
 #define PETREL   3
+/* PETREL2: Petrel 2 hardware reports ID_MODEL=PETREL (3); there is no
+ * distinct Product-Version value for it. FWID-based sub-model distinction
+ * is exposed via devinfo.hw_id on live download. */
 #define PETREL2  PETREL
 #define NERD     4
 #define PERDIX   5
@@ -93,8 +96,6 @@ dc_status_t shearwater_common_can_wdbi (shearwater_common_device_t *device, dc_b
 
 dc_status_t shearwater_common_device_timesync(dc_device_t *abstract, const dc_datetime_t *datetime);
 
-dc_status_t shearwater_common_get_model(shearwater_common_device_t *device, unsigned int *model);
-
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

src/shearwater_petrel.c

@@ -190,16 +190,33 @@ shearwater_petrel_device_foreach (dc_device_t *abstract, dc_dive_callback_t call
 	// Convert to a number.
 	unsigned int firmware = str2num (rsp_firmware, rsp_firmware_length, 1);
 
-	unsigned int model = 0;
-	rc = shearwater_common_get_model (&device->base, &model);
-	if (rc != DC_STATUS_SUCCESS)
+	// Read the model number (ID_MODEL, RDBI 0x8060) — Product-Version byte,
+	// authoritative for the coarse product family (aligns with upstream libdc).
+	unsigned char rsp_model = 0;
+	rc = shearwater_common_rdbi (&device->base, ID_MODEL, &rsp_model, sizeof(rsp_model), NULL);
+	if (rc != DC_STATUS_SUCCESS) {
+		ERROR (abstract->context, "Failed to read the model number.");
 		return rc;
+	}
+
+	// Attempt to read the hardware type (ID_HARDWARE, RDBI 0x8050) for
+	// consumer-side sub-model differentiation (e.g. Petrel 1 vs Petrel 2).
+	// Best-effort: FWID can change across firmware updates and stored logs
+	// do not carry it. Failure is non-fatal; hw_id remains 0.
+	unsigned char rsp_hardware[2] = {0};
+	unsigned int fwid = 0;
+	dc_status_t hw_rc = shearwater_common_rdbi (&device->base, ID_HARDWARE, rsp_hardware, sizeof(rsp_hardware), NULL);
+	if (hw_rc == DC_STATUS_SUCCESS) {
+		fwid = array_uint16_be (rsp_hardware);
+		DEBUG (abstract->context, "Hardware type (FWID): 0x%04x", fwid);
+	}
 
 	// Emit a device info event.
 	dc_event_devinfo_t devinfo;
-	devinfo.model = model;
+	devinfo.model = rsp_model;
 	devinfo.firmware = firmware;
 	devinfo.serial = array_uint32_be (serial);
+	device_set_hw_id (abstract, fwid);
 	device_event_emit (abstract, DC_EVENT_DEVINFO, &devinfo);
 
 	// Read the logbook type
@@ -356,15 +373,17 @@ shearwater_petrel_device_foreach (dc_device_t *abstract, dc_dive_callback_t call
 static dc_status_t
 shearwater_petrel_device_timesync (dc_device_t *abstract, const dc_datetime_t *datetime)
 {
-	dc_status_t status = DC_STATUS_SUCCESS;
 	shearwater_common_device_t *device = (shearwater_common_device_t *) abstract;
 
-	unsigned int model = 0;
-	status = shearwater_common_get_model (device, &model);
-	if (status != DC_STATUS_SUCCESS)
+	// Read ID_MODEL (RDBI 0x8060) directly to determine time-sync variant.
+	unsigned char rsp_model = 0;
+	dc_status_t status = shearwater_common_rdbi (device, ID_MODEL, &rsp_model, sizeof(rsp_model), NULL);
+	if (status != DC_STATUS_SUCCESS) {
+		ERROR (abstract->context, "Failed to read the model number.");
 		return status;
+	}
 
-	if (model == TERIC) {
+	if (rsp_model == TERIC) {
 		return shearwater_common_timesync_utc (device, datetime);
 	} else {
 		return shearwater_common_timesync_local (device, datetime);

src/shearwater_predator_parser.c

@@ -873,6 +873,11 @@ shearwater_predator_parser_cache (shearwater_predator_parser_t *parser)
 	}
 
 	// Get the correct model number from the final block.
+	// Product-Version byte from the device's final record — authoritative for
+	// the coarse product family. This value is not the FWID; stored logs do not
+	// carry the FWID, so sub-model distinctions (e.g. Petrel 1 vs Petrel 2) are
+	// not recoverable on re-parse. Consumer-side refinement uses the FWID
+	// exposed via devinfo.hw_id on live download.
 	if (parser->final != UNDEFINED) {
 		parser->model = data[parser->final + 13];
 		DEBUG (abstract->context, "Device: model=%u, serial=%u, firmware=%u",