Clean up divecomputer 'device' handling

We have this odd legacy notion of a divecomputer 'device', that was
originally just basically the libdivecomputer 'EVENT_DEVINFO' report
that was associated with each dive.  So it had firmware version,
deviceid, and serial number.

It had also gotten extended to do 'nickname' handling, and it was all
confusing, ugly and bad.  It was particularly bad because it wasn't
actually a 'per device' thing at all: due to the firmware field, a dive
computer that got a firmware update forced a new 'device'.

To make matters worse, the 'deviceid' was also almost random, because
we've calculated it a couple of different ways, and libdivecomputer
itself has changed how the legacy 32-bit 'serial number' is expressed.

Finally, because of all these issues, we didn't even try to make the
thing unique, so it really ended up being a random snapshot of the state
of the dive computer at the time of a dive, and sometimes we'd pick one,
and sometimes another, since they weren't really well-defined.

So get rid of all this confusion.

The new rules:

 - the actual random dive computer state at the time of a dive is kept
   in the dive data. So if you want to know the firmware version, it
   should be in the 'extra data'

 - the only serial number that matters is the string one in the extra
   data, because that's the one that actually matches what the dive
   computer reports, and isn't some random 32-bit integer with ambiguous
   formatting.

 - the 'device id' - the thing we match with (together with the model
   name, eg "Suunto EON Steel") is purely a hash of the real serial
   number.

   The device ID that libdivecomputer reports in EVENT_DEVINFO is
   ignored, as is the device ID we've saved in the XML or git files. If
   we have a serial number, the device ID will be uniquely associated
   with that serial number, and if we don't have one, the device ID will
   be zero (for 'match anything').

   So now 'deviceid' is literally just a shorthand for the serial number
   string, and the two are joined at the hip.

 - the 'device' managament is _only_ used to track devices that have
   serial numbers _and_ nicknames. So no more different device
   structures just because one had a nickname and the other didn't etc.

   Without a serial number, the device is 'anonymous' and fundamentally
   cannot be distinguished from other devices of the same model, so a
   nickname is meaningless. And without a nickname, there is no point in
   creating a device data structure, since all the data is in the dive
   itself and the device structure wouldn't add any value..

These rules mean that we no longer have ambiguous 'device' structures,
and we can never have duplicates that can confuse us.

This does mean that you can't give a nickname to a device that cannot be
uniquely identified with a serial number, but those are happily fairly
rare (and mostly older ones).  Dirk said he'd look at what it takes to
give more dive computers proper serial numbers, and I already did it for
the Garmin Descent family yesterday.

(Honesty in advertizing: right now you can't add a nickname to a dive
computer that doesn't already have one, because such a dive computer
will not have a device structure.  But that's a UI issue, and I'll sort
that out separately)

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

12 files changed, 70 insertions, 178 deletions

diff --git a/core/datatrak.c b/core/datatrak.c
index 2fa89010e..c19c243a5 100644
--- a/core/datatrak.c
+++ b/core/datatrak.c
@@ -566,7 +566,6 @@ static unsigned char *dt_dive_parser(unsigned char *runner, struct dive *dt_dive
 		dt_dive->dc.deviceid = 0;
 	else
 		dt_dive->dc.deviceid = 0xffffffff;
-	create_device_node(devices, dt_dive->dc.model, dt_dive->dc.deviceid, "", "", dt_dive->dc.model);
 	dt_dive->dc.next = NULL;
 	if (!is_SCR && dt_dive->cylinders.nr > 0) {
 		get_cylinder(dt_dive, 0)->end.mbar = get_cylinder(dt_dive, 0)->start.mbar -
diff --git a/core/device.cpp b/core/device.cpp
index c251144a2..42c2be004 100644
--- a/core/device.cpp
+++ b/core/device.cpp
@@ -13,31 +13,33 @@ struct device_table device_table;
 bool device::operator==(const device &a) const
 {
 	return model == a.model &&
-	       deviceId == a.deviceId &&
-	       firmware == a.firmware &&
-	       serialNumber == a.serialNumber &&
-	       nickName == a.nickName;
+	       serialNumber == a.serialNumber;
 }
 
 static bool same_device(const device &dev1, const device &dev2)
 {
-	return dev1.deviceId == dev2.deviceId && strcoll(dev1.model.c_str(), dev2.model.c_str()) == 0;
+	return strcmp(dev1.model.c_str(), dev2.model.c_str()) == 0 &&
+		strcmp(dev1.serialNumber.c_str(), dev2.serialNumber.c_str()) == 0;
 }
 
 bool device::operator<(const device &a) const
 {
-	if (deviceId != a.deviceId)
-		return deviceId < a.deviceId;
+	int diff;
 
-	// Use strcoll to compare model-strings, since these might be unicode
-	// and therefore locale dependent? Let's hope that not, but who knows?
-	return strcoll(model.c_str(), a.model.c_str()) < 0;
+	diff = strcmp(model.c_str(), a.model.c_str());
+	if (diff)
+		return diff < 0;
+
+	return strcmp(serialNumber.c_str(), a.serialNumber.c_str()) < 0;
 }
 
 extern "C" const struct device *get_device_for_dc(const struct device_table *table, const struct divecomputer *dc)
 {
+	if (!dc->model || !dc->serial)
+		return NULL;
+
 	const std::vector<device> &dcs = table->devices;
-	device dev { dc->model ?: "", dc->deviceid, {}, {}, {} };
+	device dev { dc->model, dc->serial };
 	auto it = std::lower_bound(dcs.begin(), dcs.end(), dev);
 	return it != dcs.end() && same_device(*it, dev) ? &*it : NULL;
 }
@@ -48,79 +50,51 @@ extern "C" bool device_exists(const struct device_table *device_table, const str
 	return it != device_table->devices.end() && same_device(*it, *dev);
 }
 
-/*
- * When setting the device ID, we also fill in the
- * serial number and firmware version data
- */
-extern "C" void set_dc_deviceid(struct divecomputer *dc, unsigned int deviceid, const struct device_table *device_table)
+void device::showchanges(const std::string &n) const
 {
-	if (!deviceid)
-		return;
-
-	dc->deviceid = deviceid;
-
-	// Serial and firmware can only be deduced if we know the model
-	if (empty_string(dc->model))
-		return;
-
-	const device *node = get_device_for_dc(device_table, dc);
-	if (!node)
-		return;
-
-	if (!node->serialNumber.empty() && empty_string(dc->serial)) {
-		free((void *)dc->serial);
-		dc->serial = strdup(node->serialNumber.c_str());
-	}
-	if (!node->firmware.empty() && empty_string(dc->fw_version)) {
-		free((void *)dc->fw_version);
-		dc->fw_version = strdup(node->firmware.c_str());
+	if (nickName != n) {
+		if (!n.empty())
+			qDebug("new nickname %s for DC model %s serial %s", n.c_str(), model.c_str(), serialNumber.c_str());
+		else
+			qDebug("deleted nickname %s for DC model %s serial %s", nickName.c_str(), model.c_str(), serialNumber.c_str());
 	}
 }
 
-void device::showchanges(const std::string &n, const std::string &s, const std::string &f) const
+static int addDC(std::vector<device> &dcs, const std::string &m, const std::string &s, const std::string &n)
 {
-	if (nickName != n && !n.empty())
-		qDebug("new nickname %s for DC model %s deviceId 0x%x", n.c_str(), model.c_str(), deviceId);
-	if (serialNumber != s && !s.empty())
-		qDebug("new serial number %s for DC model %s deviceId 0x%x", s.c_str(), model.c_str(), deviceId);
-	if (firmware != f && !f.empty())
-		qDebug("new firmware version %s for DC model %s deviceId 0x%x", f.c_str(), model.c_str(), deviceId);
-}
-
-static void addDC(std::vector<device> &dcs, const std::string &m, uint32_t d, const std::string &n, const std::string &s, const std::string &f)
-{
-	if (m.empty() || d == 0)
-		return;
-	device dev { m, d, {}, {}, {} };
+	if (m.empty() || s.empty())
+		return -1;
+	device dev { m, s, n };
 	auto it = std::lower_bound(dcs.begin(), dcs.end(), dev);
 	if (it != dcs.end() && same_device(*it, dev)) {
 		// debugging: show changes
 		if (verbose)
-			it->showchanges(n, s, f);
+			it->showchanges(n);
 		// Update any non-existent fields from the old entry
-		if (!n.empty())
-			it->nickName = n;
-		if (!s.empty())
-			it->serialNumber = s;
-		if (!f.empty())
-			it->firmware = f;
+		if (n.empty()) {
+			dcs.erase(it);
+			return -1;
+		}
+		it->nickName = n;
+		return it - dcs.begin();
 	} else {
-		dcs.insert(it, device{m, d, s, f, n});
+		if (n.empty())
+			return -1;
+
+		dev.deviceId = calculate_string_hash(s.c_str());
+		dcs.insert(it, dev);
+		return it - dcs.begin();
 	}
 }
 
-extern "C" void create_device_node(struct device_table *device_table, const char *model, uint32_t deviceid, const char *serial, const char *firmware, const char *nickname)
+extern "C" int create_device_node(struct device_table *device_table, const char *model, const char *serial, const char *nickname)
 {
-	addDC(device_table->devices, model ?: "", deviceid, nickname ?: "", serial ?: "", firmware ?: "");
+	return addDC(device_table->devices, model ?: "", serial ?: "", nickname ?: "");
 }
 
-/* Does not check for duplicates! */
 extern "C" int add_to_device_table(struct device_table *device_table, const struct device *dev)
 {
-	auto it = std::lower_bound(device_table->devices.begin(), device_table->devices.end(), *dev);
-	int idx = it - device_table->devices.begin();
-	device_table->devices.insert(it, *dev);
-	return idx;
+	return create_device_node(device_table, dev->model.c_str(), dev->serialNumber.c_str(), dev->nickName.c_str());
 }
 
 extern "C" int remove_device(struct device_table *device_table, const struct device *dev)
@@ -165,34 +139,6 @@ extern "C" int is_default_dive_computer_device(const char *name)
 	return qPrefDiveComputer::device() == name;
 }
 
-extern "C" void add_devices_of_dive(const struct dive *dive, struct device_table *device_table)
-{
-	if (!dive)
-		return;
-
-	const struct divecomputer *dc;
-
-	for_each_dc (dive, dc) {
-		if (!empty_string(dc->model) && dc->deviceid &&
-		    !get_device_for_dc(device_table, dc)) {
-			// we don't have this one, yet
-			if (std::any_of(device_table->devices.begin(), device_table->devices.end(),
-				        [dc] (const device &dev)
-				        { return !strcasecmp(dev.model.c_str(), dc->model); })) {
-				// we already have this model but a different deviceid
-				std::string simpleNick(dc->model);
-				if (dc->deviceid == 0)
-					simpleNick += " (unknown deviceid)";
-				else
-					simpleNick += " (" + QString::number(dc->deviceid, 16).toStdString() + ")";
-				addDC(device_table->devices, dc->model, dc->deviceid, simpleNick, {}, {});
-			} else {
-				addDC(device_table->devices, dc->model, dc->deviceid, {}, {}, {});
-			}
-		}
-	}
-}
-
 const char *get_dc_nickname(const struct divecomputer *dc)
 {
 	const device *existNode = get_device_for_dc(&device_table, dc);
@@ -227,21 +173,11 @@ extern "C" const char *device_get_model(const struct device *dev)
 	return dev ? dev->model.c_str() : NULL;
 }
 
-extern "C" const uint32_t device_get_id(const struct device *dev)
-{
-	return dev ? dev->deviceId : -1;
-}
-
 extern "C" const char *device_get_serial(const struct device *dev)
 {
 	return dev ? dev->serialNumber.c_str() : NULL;
 }
 
-extern "C" const char *device_get_firmware(const struct device *dev)
-{
-	return dev ? dev->firmware.c_str() : NULL;
-}
-
 extern "C" const char *device_get_nickname(const struct device *dev)
 {
 	return dev ? dev->nickName.c_str() : NULL;
diff --git a/core/device.h b/core/device.h
index 1de436e33..6bfb85e3c 100644
--- a/core/device.h
+++ b/core/device.h
@@ -16,10 +16,7 @@ struct dive_table;
 // global device table
 extern struct device_table device_table;
 
-extern void set_dc_deviceid(struct divecomputer *dc, unsigned int deviceid, const struct device_table *table);
-
-extern void add_devices_of_dive(const struct dive *dive, struct device_table *table);
-extern void create_device_node(struct device_table *table, const char *model, uint32_t deviceid, const char *serial, const char *firmware, const char *nickname);
+extern int create_device_node(struct device_table *table, const char *model, const char *serial, const char *nickname);
 extern int nr_devices(const struct device_table *table);
 extern const struct device *get_device(const struct device_table *table, int i);
 extern struct device *get_device_mutable(struct device_table *table, int i);
@@ -35,9 +32,7 @@ extern void remove_from_device_table(struct device_table *table, int idx);
 
 // struct device accessors for C-code. The returned strings are not stable!
 const char *device_get_model(const struct device *dev);
-const uint32_t device_get_id(const struct device *dev);
 const char *device_get_serial(const struct device *dev);
-const char *device_get_firmware(const struct device *dev);
 const char *device_get_nickname(const struct device *dev);
 
 // for C code that needs to alloc/free a device table. (Let's try to get rid of those)
@@ -56,16 +51,15 @@ extern void free_device_table(struct device_table *devices);
 struct device {
 	bool operator==(const device &a) const; // TODO: remove, once devices are integrated in the undo system
 	bool operator<(const device &a) const;
-	void showchanges(const std::string &n, const std::string &s, const std::string &f) const;
+	void showchanges(const std::string &n) const;
 	std::string model;
-	uint32_t deviceId;
 	std::string serialNumber;
-	std::string firmware;
 	std::string nickName;
+	uint32_t deviceId;	// Always the string hash of the serialNumber
 };
 
 struct device_table {
-	// Keep the dive computers in a vector sorted by (model, deviceId)
+	// Keep the dive computers in a vector sorted by (model, serial)
 	std::vector<device> devices;
 };
 
diff --git a/core/divecomputer.c b/core/divecomputer.c
index fa836f7ca..200094588 100644
--- a/core/divecomputer.c
+++ b/core/divecomputer.c
@@ -475,6 +475,9 @@ void add_extra_data(struct divecomputer *dc, const char *key, const char *value)
 {
 	struct extra_data **ed = &dc->extra_data;
 
+	if (!strcasecmp(key, "Serial"))
+		dc->deviceid = calculate_string_hash(value);
+
 	while (*ed)
 		ed = &(*ed)->next;
 	*ed = malloc(sizeof(struct extra_data));
diff --git a/core/divecomputer.h b/core/divecomputer.h
index eb48e9b86..8bb571c44 100644
--- a/core/divecomputer.h
+++ b/core/divecomputer.h
@@ -68,6 +68,7 @@ extern struct event *add_event(struct divecomputer *dc, unsigned int time, int t
 extern void remove_event_from_dc(struct divecomputer *dc, struct event *event);
 extern void add_extra_data(struct divecomputer *dc, const char *key, const char *value);
 extern bool is_dc_planner(const struct divecomputer *dc);
+extern uint32_t calculate_string_hash(const char *str);
 
 /* Check if two dive computer entries are the exact same dive (-1=no/0=maybe/1=yes) */
 extern int match_one_dc(const struct divecomputer *a, const struct divecomputer *b);
diff --git a/core/divelist.c b/core/divelist.c
index a1420e407..9beea4d7c 100644
--- a/core/divelist.c
+++ b/core/divelist.c
@@ -807,13 +807,6 @@ void delete_single_dive(int idx)
 
 void process_loaded_dives()
 {
-	int i;
-	struct dive *dive;
-
-	/* Register dive computer nick names. */
-	for_each_dive(i, dive)
-		add_devices_of_dive(dive, &device_table);
-
 	sort_dive_table(&dive_table);
 	sort_trip_table(&trip_table);
 
@@ -1172,17 +1165,6 @@ void process_imported_dives(struct dive_table *import_table, struct trip_table *
 			add_to_device_table(devices_to_add, dev);
 	}
 
-	/* check if we need a nickname for the divecomputer for newly downloaded dives;
-	 * since we know they all came from the same divecomputer we just check for the
-	 * first one */
-	if (flags & IMPORT_IS_DOWNLOADED) {
-		add_devices_of_dive(import_table->dives[0], devices_to_add);
-	} else {
-		/* they aren't downloaded, so record / check all new ones */
-		for (i = 0; i < import_table->nr; i++)
-			add_devices_of_dive(import_table->dives[i], devices_to_add);
-	}
-
 	/* Sort the table of dives to be imported and combine mergable dives */
 	sort_dive_table(import_table);
 	merge_imported_dives(import_table);
diff --git a/core/libdivecomputer.c b/core/libdivecomputer.c
index dff44e287..d2d25306d 100644
--- a/core/libdivecomputer.c
+++ b/core/libdivecomputer.c
@@ -548,7 +548,7 @@ static uint32_t calculate_diveid(const unsigned char *fingerprint, unsigned int
 	return csum[0];
 }
 
-static uint32_t calculate_string_hash(const char *str)
+uint32_t calculate_string_hash(const char *str)
 {
 	return calculate_diveid((const unsigned char *)str, strlen(str));
 }
@@ -556,10 +556,7 @@ static uint32_t calculate_string_hash(const char *str)
 /*
  * Set the serial number.
  *
- * This also sets the device ID by looking for existing devices that
- * have that serial number.
- *
- * If no existing device ID exists, create a new by hashing the serial
+ * This also sets the device ID by hashing the serial
  * number string.
  */
 static void set_dc_serial(struct divecomputer *dc, const char *serial, const device_data_t *devdata)
@@ -567,14 +564,7 @@ static void set_dc_serial(struct divecomputer *dc, const char *serial, const dev
 	const struct device *device;
 
 	dc->serial = strdup(serial);
-	if ((device = get_device_for_dc(&device_table, dc)) != NULL)	// prefer already known ID over downloaded ID.
-		dc->deviceid = device_get_id(device);
-
-	if (!dc->deviceid && (device = get_device_for_dc(devdata->devices, dc)) != NULL)
-		dc->deviceid = device_get_id(device);
-
-	if (!dc->deviceid)
-		dc->deviceid = calculate_string_hash(serial);
+	dc->deviceid = calculate_string_hash(serial);
 }
 
 static void parse_string_field(device_data_t *devdata, struct dive *dive, dc_field_string_t *str)
@@ -937,7 +927,6 @@ static unsigned int fixup_suunto_versions(device_data_t *devdata, const dc_event
 			 (devinfo->firmware >> 8) & 0xff,
 			 (devinfo->firmware >> 0) & 0xff);
 	}
-	create_device_node(devdata->devices, devdata->model, devdata->deviceid, serial_nr, firmware, "");
 
 	return serial;
 }
diff --git a/core/load-git.c b/core/load-git.c
index c44a880ae..3826099e4 100644
--- a/core/load-git.c
+++ b/core/load-git.c
@@ -725,8 +725,7 @@ static void parse_dc_deviceid(char *line, struct membuffer *str, struct git_pars
 {
 	UNUSED(str);
 	int id = get_hex(line);
-	set_dc_deviceid(state->active_dc, id, &device_table); // prefer already known serial/firmware over those from the loaded log
-	set_dc_deviceid(state->active_dc, id, state->devices);
+	UNUSED(id);	// legacy
 }
 
 static void parse_dc_diveid(char *line, struct membuffer *str, struct git_parser_state *state)
@@ -974,16 +973,16 @@ static void parse_divecomputerid_keyvalue(void *_cid, const char *key, const cha
 {
 	struct divecomputerid *cid = _cid;
 
-	if (!strcmp(key, "deviceid")) {
-		cid->deviceid = get_hex(value);
+	// Ignored legacy fields
+	if (!strcmp(key, "firmware"))
 		return;
-	}
+	if (!strcmp(key, "deviceid"))
+		return;
+
+	// Serial number and nickname matter
 	if (!strcmp(key, "serial")) {
 		cid->serial = value;
-		return;
-	}
-	if (!strcmp(key, "firmware")) {
-		cid->firmware = value;
+		cid->deviceid = calculate_string_hash(value);
 		return;
 	}
 	if (!strcmp(key, "nickname")) {
@@ -1014,7 +1013,7 @@ static void parse_settings_divecomputerid(char *line, struct membuffer *str, str
 			break;
 		line = parse_keyvalue_entry(parse_divecomputerid_keyvalue, &id, line, str);
 	}
-	create_device_node(state->devices, id.model, id.deviceid, id.serial, id.firmware, id.nickname);
+	create_device_node(state->devices, id.model, id.serial, id.nickname);
 }
 
 static void parse_picture_filename(char *line, struct membuffer *str, struct git_parser_state *state)
diff --git a/core/parse-xml.c b/core/parse-xml.c
index c5864d6f5..5b9abc341 100644
--- a/core/parse-xml.c
+++ b/core/parse-xml.c
@@ -830,11 +830,8 @@ static void try_to_fill_dc(struct divecomputer *dc, const char *name, char *buf,
 		return;
 	if (MATCH("model", utf8_string, &dc->model))
 		return;
-	if (MATCH("deviceid", hex_value, &deviceid)) {
-		set_dc_deviceid(dc, deviceid, &device_table); // prefer already known serial/firmware over those from the loaded log
-		set_dc_deviceid(dc, deviceid, state->devices);
+	if (MATCH("deviceid", hex_value, &deviceid))
 		return;
-	}
 	if (MATCH("diveid", hex_value, &dc->diveid))
 		return;
 	if (MATCH("dctype", get_dc_type, &dc->divemode))
diff --git a/core/parse.c b/core/parse.c
index 241d5763f..fdc73fc9f 100644
--- a/core/parse.c
+++ b/core/parse.c
@@ -203,8 +203,10 @@ void dc_settings_start(struct parser_state *state)
 
 void dc_settings_end(struct parser_state *state)
 {
-	create_device_node(state->devices, state->cur_settings.dc.model, state->cur_settings.dc.deviceid, state->cur_settings.dc.serial_nr,
-			   state->cur_settings.dc.firmware, state->cur_settings.dc.nickname);
+	create_device_node(state->devices,
+		state->cur_settings.dc.model,
+		state->cur_settings.dc.serial_nr,
+		state->cur_settings.dc.nickname);
 	reset_dc_settings(state);
 }
 
diff --git a/core/save-git.c b/core/save-git.c
index cea69974b..6bd237a8b 100644
--- a/core/save-git.c
+++ b/core/save-git.c
@@ -853,19 +853,15 @@ static void save_one_device(struct membuffer *b, const struct device *d)
 	const char *model = device_get_model(d);
 	const char *nickname = device_get_nickname(d);
 	const char *serial = device_get_serial(d);
-	const char *firmware = device_get_firmware(d);
-	if (!empty_string(nickname) && !strcmp(model, nickname))
-		nickname = NULL;
+
 	if (empty_string(serial)) serial = NULL;
-	if (empty_string(firmware)) firmware = NULL;
 	if (empty_string(nickname)) nickname = NULL;
-	if (!nickname && !serial && !firmware)
+	if (!nickname || !serial)
 		return;
 
 	show_utf8(b, "divecomputerid ", model, "");
-	put_format(b, " deviceid=%08x", device_get_id(d));
+	put_format(b, " deviceid=%08x", calculate_string_hash(serial));
 	show_utf8(b, " serial=", serial, "");
-	show_utf8(b, " firmware=", firmware, "");
 	show_utf8(b, " nickname=", nickname, "");
 	put_string(b, "\n");
 }
diff --git a/core/save-xml.c b/core/save-xml.c
index 4c7c2ee04..3836ea35c 100644
--- a/core/save-xml.c
+++ b/core/save-xml.c
@@ -583,29 +583,23 @@ static void save_one_device(struct membuffer *b, const struct device *d)
 	const char *model = device_get_model(d);
 	const char *nickname = device_get_nickname(d);
 	const char *serial_nr = device_get_serial(d);
-	const char *firmware = device_get_firmware(d);
 
 	/* Nicknames that are empty or the same as the device model are not interesting */
 	if (empty_string(nickname) || !strcmp(model, nickname))
-			nickname = NULL;
+		nickname = NULL;
 
 	/* Serial numbers that are empty are not interesting */
 	if (empty_string(serial_nr))
 		serial_nr = NULL;
 
-	/* Firmware strings that are empty are not interesting */
-	if (empty_string(firmware))
-		firmware = NULL;
-
 	/* Do we have anything interesting about this dive computer to save? */
-	if (!serial_nr && !nickname && !firmware)
+	if (!serial_nr || !nickname)
 		return;
 
 	put_format(b, "<divecomputerid");
 	show_utf8(b, model, " model='", "'", 1);
-	put_format(b, " deviceid='%08x'", device_get_id(d));
+	put_format(b, " deviceid='%08x'", calculate_string_hash(serial_nr));
 	show_utf8(b, serial_nr, " serial='", "'", 1);
-	show_utf8(b, firmware, " firmware='", "'", 1);
 	show_utf8(b, nickname, " nickname='", "'", 1);
 	put_format(b, "/>\n");
 }