Bluetooth: Audio: Change lang to 3-byte value from uint32_t

The 3-byte value suits the assigned number much better,
and also allows for less memory copies when getting and
setting the values.

Signed-off-by: Emil Gydesen <[email protected]>

doc/releases/migration-guide-3.7.rst

@@ -454,6 +454,15 @@ Bluetooth Audio
   :c:func:`bt_audio_codec_cfg_meta_set_lang`
   :c:func:`bt_audio_codec_cfg_meta_get_lang`
 
+* Changed ``lang`` from ``uint32_t`` to ``uint8_t [3]``. This modifies the following functions
+  - :c:func:`bt_audio_codec_cap_meta_set_lang`
+  - :c:func:`bt_audio_codec_cap_meta_get_lang`
+  - :c:func:`bt_audio_codec_cfg_meta_set_lang`
+  - :c:func:`bt_audio_codec_cfg_meta_get_lang`
+
+  The result of this is that string values such as ``"eng"`` and ``"deu"`` can now be used to set
+  new values, and to prevent unnecessary copies of data when getting the values.
+
 * All occurrences of ``set_sirk`` have been changed to just ``sirk`` as the ``s`` in ``sirk`` stands
   for set. (:github:`73413`)
 

include/zephyr/bluetooth/audio/audio.h

@@ -41,6 +41,9 @@ extern "C" {
 
 #define BT_AUDIO_BROADCAST_CODE_SIZE             16
 
+/** Size of the stream language value, e.g. "eng" */
+#define BT_AUDIO_LANG_SIZE 3
+
 /**
  * @brief Codec capability types
  *
@@ -376,6 +379,7 @@ enum bt_audio_metadata_type {
 	/** @brief Language
 	 *
 	 * 3 octet lower case language code defined by ISO 639-3
+	 * Possible values can be found at https://iso639-3.sil.org/code_tables/639/data
 	 */
 	BT_AUDIO_METADATA_TYPE_LANG                = 0x04,
 
@@ -1212,14 +1216,16 @@ int bt_audio_codec_cfg_meta_set_program_info(struct bt_audio_codec_cfg *codec_cf
  *
  *  See @ref BT_AUDIO_METADATA_TYPE_LANG for more information about this value.
  *
- *  @param codec_cfg The codec data to search in.
+ *  @param[in]  codec_cfg The codec data to search in.
+ *  @param[out] lang      Pointer to the language bytes (of length BT_AUDIO_LANG_SIZE)
  *
  *  @retval The language if positive or 0
  *  @retval -EINVAL if arguments are invalid
  *  @retval -ENODATA if not found
  *  @retval -EBADMSG if found value has invalid size
  */
-int bt_audio_codec_cfg_meta_get_lang(const struct bt_audio_codec_cfg *codec_cfg);
+int bt_audio_codec_cfg_meta_get_lang(const struct bt_audio_codec_cfg *codec_cfg,
+				     const uint8_t **lang);
 
 /**
  * @brief Set the language of a codec configuration metadata.
@@ -1231,7 +1237,8 @@ int bt_audio_codec_cfg_meta_get_lang(const struct bt_audio_codec_cfg *codec_cfg)
  * @retval -EINVAL if arguments are invalid
  * @retval -ENOMEM if the new value could not set or added due to memory
  */
-int bt_audio_codec_cfg_meta_set_lang(struct bt_audio_codec_cfg *codec_cfg, uint32_t lang);
+int bt_audio_codec_cfg_meta_set_lang(struct bt_audio_codec_cfg *codec_cfg,
+				     const uint8_t lang[BT_AUDIO_LANG_SIZE]);
 
 /** @brief Extract CCID list
  *
@@ -1734,14 +1741,16 @@ int bt_audio_codec_cap_meta_set_program_info(struct bt_audio_codec_cap *codec_ca
  *
  *  See @ref BT_AUDIO_METADATA_TYPE_LANG for more information about this value.
  *
- *  @param codec_cap The codec data to search in.
+ *  @param[in]  codec_cap The codec data to search in.
+ *  @param[out] lang      Pointer to the language bytes (of length BT_AUDIO_LANG_SIZE)
  *
- *  @retval The language if positive or 0
+ *  @retval 0 On success
  *  @retval -EINVAL if arguments are invalid
  *  @retval -ENODATA if not found
  *  @retval -EBADMSG if found value has invalid size
  */
-int bt_audio_codec_cap_meta_get_lang(const struct bt_audio_codec_cap *codec_cap);
+int bt_audio_codec_cap_meta_get_lang(const struct bt_audio_codec_cap *codec_cap,
+				     const uint8_t **lang);
 
 /**
  * @brief Set the language of a codec capability metadata.
@@ -1753,7 +1762,8 @@ int bt_audio_codec_cap_meta_get_lang(const struct bt_audio_codec_cap *codec_cap)
  * @retval -EINVAL if arguments are invalid
  * @retval -ENOMEM if the new value could not set or added due to memory
  */
-int bt_audio_codec_cap_meta_set_lang(struct bt_audio_codec_cap *codec_cap, uint32_t lang);
+int bt_audio_codec_cap_meta_set_lang(struct bt_audio_codec_cap *codec_cap,
+				     const uint8_t lang[BT_AUDIO_LANG_SIZE]);
 
 /** @brief Extract CCID list
  *

subsys/bluetooth/audio/ascs.c

@@ -2098,7 +2098,7 @@ static bool ascs_parse_metadata(struct bt_data *data, void *user_data)
 		break;
 	}
 	case BT_AUDIO_METADATA_TYPE_LANG:
-		if (data_len != 3) {
+		if (data_len != BT_AUDIO_LANG_SIZE) {
 			*result->rsp = BT_BAP_ASCS_RSP(BT_BAP_ASCS_RSP_CODE_METADATA_INVALID,
 						       data_type);
 			result->err = -EBADMSG;

subsys/bluetooth/audio/codec.c

@@ -796,7 +796,7 @@ static int codec_meta_set_program_info(uint8_t meta[], size_t meta_len, size_t m
 				  program_info, program_info_len);
 }
 
-static int codec_meta_get_lang(const uint8_t meta[], size_t meta_len)
+static int codec_meta_get_lang(const uint8_t meta[], size_t meta_len, const uint8_t **lang)
 {
 	const uint8_t *data;
 	int ret;
@@ -806,36 +806,40 @@ static int codec_meta_get_lang(const uint8_t meta[], size_t meta_len)
 		return -EINVAL;
 	}
 
+	CHECKIF(lang == NULL) {
+		LOG_DBG("lang is NULL");
+		return -EINVAL;
+	}
+
 	ret = codec_meta_get_val(meta, meta_len, BT_AUDIO_METADATA_TYPE_LANG, &data);
 	if (data == NULL) {
 		return -ENODATA;
 	}
 
-	if (ret != 3) { /* Language is 3 octets */
+	if (ret != BT_AUDIO_LANG_SIZE) {
 		return -EBADMSG;
 	}
 
-	return sys_get_le24(data);
+	*lang = data;
+
+	return 0;
 }
 
-static int codec_meta_set_lang(uint8_t meta[], size_t meta_len, size_t meta_size, uint32_t lang)
+static int codec_meta_set_lang(uint8_t meta[], size_t meta_len, size_t meta_size,
+			       const uint8_t lang[BT_AUDIO_LANG_SIZE])
 {
-	uint8_t lang_le[3];
-
 	CHECKIF(meta == NULL) {
 		LOG_DBG("meta is NULL");
 		return -EINVAL;
 	}
 
-	if ((lang & 0xFFFFFFU) != lang) {
-		LOG_DBG("Invalid lang value: %d", lang);
+	CHECKIF(lang == NULL) {
+		LOG_DBG("lang is NULL");
 		return -EINVAL;
 	}
 
-	sys_put_le24(lang, lang_le);
-
-	return codec_meta_set_val(meta, meta_len, meta_size, BT_AUDIO_METADATA_TYPE_LANG, lang_le,
-				  sizeof(lang_le));
+	return codec_meta_set_val(meta, meta_len, meta_size, BT_AUDIO_METADATA_TYPE_LANG, lang,
+				  BT_AUDIO_LANG_SIZE);
 }
 
 static int codec_meta_get_ccid_list(const uint8_t meta[], size_t meta_len,
@@ -1247,17 +1251,19 @@ int bt_audio_codec_cfg_meta_set_program_info(struct bt_audio_codec_cfg *codec_cf
 	return ret;
 }
 
-int bt_audio_codec_cfg_meta_get_lang(const struct bt_audio_codec_cfg *codec_cfg)
+int bt_audio_codec_cfg_meta_get_lang(const struct bt_audio_codec_cfg *codec_cfg,
+				     const uint8_t **lang)
 {
 	CHECKIF(codec_cfg == NULL) {
 		LOG_DBG("codec_cfg is NULL");
 		return -EINVAL;
 	}
 
-	return codec_meta_get_lang(codec_cfg->meta, codec_cfg->meta_len);
+	return codec_meta_get_lang(codec_cfg->meta, codec_cfg->meta_len, lang);
 }
 
-int bt_audio_codec_cfg_meta_set_lang(struct bt_audio_codec_cfg *codec_cfg, uint32_t lang)
+int bt_audio_codec_cfg_meta_set_lang(struct bt_audio_codec_cfg *codec_cfg,
+				     const uint8_t lang[BT_AUDIO_LANG_SIZE])
 {
 	int ret;
 
@@ -1573,17 +1579,19 @@ int bt_audio_codec_cap_meta_set_program_info(struct bt_audio_codec_cap *codec_ca
 	return ret;
 }
 
-int bt_audio_codec_cap_meta_get_lang(const struct bt_audio_codec_cap *codec_cap)
+int bt_audio_codec_cap_meta_get_lang(const struct bt_audio_codec_cap *codec_cap,
+				     const uint8_t **lang)
 {
 	CHECKIF(codec_cap == NULL) {
 		LOG_DBG("codec_cap is NULL");
 		return -EINVAL;
 	}
 
-	return codec_meta_get_lang(codec_cap->meta, codec_cap->meta_len);
+	return codec_meta_get_lang(codec_cap->meta, codec_cap->meta_len, lang);
 }
 
-int bt_audio_codec_cap_meta_set_lang(struct bt_audio_codec_cap *codec_cap, uint32_t lang)
+int bt_audio_codec_cap_meta_set_lang(struct bt_audio_codec_cap *codec_cap,
+				     const uint8_t lang[BT_AUDIO_LANG_SIZE])
 {
 	int ret;
 

subsys/bluetooth/audio/shell/audio.h

@@ -361,14 +361,11 @@ static inline void print_codec_meta_program_info(const struct shell *sh, size_t
 	shell_fprintf(sh, SHELL_NORMAL, "\n");
 }
 
-static inline void print_codec_meta_language(const struct shell *sh, size_t indent, uint32_t lang)
+static inline void print_codec_meta_language(const struct shell *sh, size_t indent,
+					     const uint8_t lang[BT_AUDIO_LANG_SIZE])
 {
-	uint8_t lang_array[3];
-
-	sys_put_be24(lang, lang_array);
-
-	shell_print(sh, "%*sLanguage: %c%c%c", indent, "", (char)lang_array[0], (char)lang_array[1],
-		    (char)lang_array[2]);
+	shell_print(sh, "%*sLanguage: %c%c%c", indent, "", (char)lang[0], (char)lang[1],
+		    (char)lang[2]);
 }
 
 static inline void print_codec_meta_ccid_list(const struct shell *sh, size_t indent,
@@ -720,9 +717,9 @@ static inline void print_codec_cap(const struct shell *sh, size_t indent,
 			print_codec_meta_program_info(sh, indent, data, (uint8_t)ret);
 		}
 
-		ret = bt_audio_codec_cap_meta_get_lang(codec_cap);
+		ret = bt_audio_codec_cap_meta_get_lang(codec_cap, &data);
 		if (ret >= 0) {
-			print_codec_meta_language(sh, indent, (uint32_t)ret);
+			print_codec_meta_language(sh, indent, data);
 		}
 
 		ret = bt_audio_codec_cap_meta_get_ccid_list(codec_cap, &data);
@@ -956,9 +953,9 @@ static inline void print_codec_cfg(const struct shell *sh, size_t indent,
 			print_codec_meta_program_info(sh, indent, data, (uint8_t)ret);
 		}
 
-		ret = bt_audio_codec_cfg_meta_get_lang(codec_cfg);
+		ret = bt_audio_codec_cfg_meta_get_lang(codec_cfg, &data);
 		if (ret >= 0) {
-			print_codec_meta_language(sh, indent, (uint32_t)ret);
+			print_codec_meta_language(sh, indent, data);
 		}
 
 		ret = bt_audio_codec_cfg_meta_get_ccid_list(codec_cfg, &data);

subsys/bluetooth/audio/shell/bap.c

@@ -1948,17 +1948,15 @@ static ssize_t parse_config_meta_args(const struct shell *sh, size_t argn, size_
 
 			arg = argv[argn];
 
-			if (strlen(arg) != 3) {
+			if (strlen(arg) != BT_AUDIO_LANG_SIZE) {
 				shell_error(sh, "Failed to parse lang from %s", arg);
 
 				return -1;
 			}
 
-			val = sys_get_le24(arg);
-
-			err = bt_audio_codec_cfg_meta_set_lang(codec_cfg, (uint32_t)val);
+			err = bt_audio_codec_cfg_meta_set_lang(codec_cfg, arg);
 			if (err < 0) {
-				shell_error(sh, "Failed to set lang with value %lu: %d", val, err);
+				shell_error(sh, "Failed to set lang with value %s: %d", arg, err);
 
 				return -1;
 			}

tests/bluetooth/audio/codec/src/main.c

@@ -517,34 +517,38 @@ ZTEST(audio_codec_test_suite, test_bt_audio_codec_cfg_meta_set_program_info)
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cfg_meta_get_lang)
 {
-	const uint32_t expected_data = sys_get_le24((uint8_t[]){'e', 'n', 'g'});
 	const struct bt_audio_codec_cfg codec_cfg = BT_AUDIO_CODEC_CFG(
 		BT_HCI_CODING_FORMAT_LC3, 0x0000, 0x0000, {},
 		{BT_AUDIO_CODEC_DATA(BT_AUDIO_METADATA_TYPE_LANG, 'e', 'n', 'g')});
+	char expected_data[] = "eng";
+	const uint8_t *lang;
 	int ret;
 
-	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg);
-	zassert_equal(ret, expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(expected_data, lang, BT_AUDIO_LANG_SIZE);
 }
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cfg_meta_set_lang)
 {
-	const uint32_t expected_data = sys_get_le24((uint8_t[]){'e', 'n', 'g'});
-	const uint32_t new_expected_data = sys_get_le24((uint8_t[]){'d', 'e', 'u'});
 	struct bt_audio_codec_cfg codec_cfg = BT_AUDIO_CODEC_CFG(
 		BT_HCI_CODING_FORMAT_LC3, 0x0000, 0x0000, {},
 		{BT_AUDIO_CODEC_DATA(BT_AUDIO_METADATA_TYPE_LANG, 'e', 'n', 'g')});
-	const uint32_t new_lang = sys_le32_to_cpu(new_expected_data);
+	char new_expected_data[] = "deu";
+	char expected_data[] = "eng";
+	const uint8_t *lang;
 	int ret;
 
-	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg);
-	zassert_equal(ret, expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(expected_data, lang, BT_AUDIO_LANG_SIZE);
 
-	ret = bt_audio_codec_cfg_meta_set_lang(&codec_cfg, new_lang);
+	ret = bt_audio_codec_cfg_meta_set_lang(&codec_cfg, new_expected_data);
 	zassert_true(ret > 0, "Unexpected return value %d", ret);
 
-	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg);
-	zassert_equal(ret, new_expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cfg_meta_get_lang(&codec_cfg, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(new_expected_data, lang, BT_AUDIO_LANG_SIZE);
 }
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cfg_meta_get_ccid_list)
@@ -1410,34 +1414,38 @@ ZTEST(audio_codec_test_suite, test_bt_audio_codec_cap_meta_set_program_info)
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cap_meta_get_lang)
 {
-	const uint32_t expected_data = sys_get_le24((uint8_t[]){'e', 'n', 'g'});
 	const struct bt_audio_codec_cap codec_cap = BT_AUDIO_CODEC_CAP(
 		BT_HCI_CODING_FORMAT_LC3, 0x0000, 0x0000, {},
 		{BT_AUDIO_CODEC_DATA(BT_AUDIO_METADATA_TYPE_LANG, 'e', 'n', 'g')});
+	char expected_data[] = "eng";
+	const uint8_t *lang;
 	int ret;
 
-	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap);
-	zassert_equal(ret, expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(expected_data, lang, BT_AUDIO_LANG_SIZE);
 }
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cap_meta_set_lang)
 {
-	const uint32_t expected_data = sys_get_le24((uint8_t[]){'e', 'n', 'g'});
-	const uint32_t new_expected_data = sys_get_le24((uint8_t[]){'d', 'e', 'u'});
 	struct bt_audio_codec_cap codec_cap = BT_AUDIO_CODEC_CAP(
 		BT_HCI_CODING_FORMAT_LC3, 0x0000, 0x0000, {},
 		{BT_AUDIO_CODEC_DATA(BT_AUDIO_METADATA_TYPE_LANG, 'e', 'n', 'g')});
-	const uint32_t new_lang = sys_le32_to_cpu(new_expected_data);
+	char new_expected_data[] = "deu";
+	char expected_data[] = "eng";
+	const uint8_t *lang;
 	int ret;
 
-	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap);
-	zassert_equal(ret, expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(expected_data, lang, BT_AUDIO_LANG_SIZE);
 
-	ret = bt_audio_codec_cap_meta_set_lang(&codec_cap, new_lang);
+	ret = bt_audio_codec_cap_meta_set_lang(&codec_cap, new_expected_data);
 	zassert_true(ret > 0, "Unexpected return value %d", ret);
 
-	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap);
-	zassert_equal(ret, new_expected_data, "Unexpected return value %d", ret);
+	ret = bt_audio_codec_cap_meta_get_lang(&codec_cap, &lang);
+	zassert_equal(ret, 0, "Unexpected return value %d", ret);
+	zassert_mem_equal(new_expected_data, lang, BT_AUDIO_LANG_SIZE);
 }
 
 ZTEST(audio_codec_test_suite, test_bt_audio_codec_cap_meta_get_ccid_list)

tests/bsim/bluetooth/audio/src/bap_common.h

@@ -63,7 +63,7 @@ static inline bool valid_metadata_type(uint8_t type, uint8_t len)
 
 		return true;
 	case BT_AUDIO_METADATA_TYPE_LANG:
-		if (len != 3) {
+		if (len != BT_AUDIO_LANG_SIZE) {
 			return false;
 		}