zbus: add zbus_chan_from_name() function

Add a new API function zbus_chan_from_name() that allows retrieving a
zbus channel by its name string. This complements the existing
zbus_chan_from_id() function and provides more flexibility for channel
lookup operations.

The function performs a linear search through all channels using
STRUCT_SECTION_FOREACH and compares channel names using strcmp(). It
returns NULL if no matching channel is found, maintaining consistency
with the existing zbus_chan_from_id() API.

The implementation is conditionally compiled when CONFIG_ZBUS_CHANNEL_NAME
is enabled, ensuring it's only available when channel names are configured
in the system.

Signed-off-by: Trond F. Christiansen <[email protected]>

Author: Trond-F-Christiansen

include/zephyr/zbus/zbus.h

@@ -690,6 +690,20 @@ const struct zbus_channel *zbus_chan_from_id(uint32_t channel_id);
 
 #endif
 
+#if defined(CONFIG_ZBUS_CHANNEL_NAME) || defined(__DOXYGEN__)
+
+/**
+ * @brief Retrieve a zbus channel from its name string
+ *
+ * @param name Name of the channel to retrieve.
+ *
+ * @retval NULL If channel with name @a name does not exist.
+ * @retval chan Channel pointer with name @a name otherwise.
+ */
+const struct zbus_channel *zbus_chan_from_name(const char *name);
+
+#endif
+
 /**
  * @brief Get the reference for a channel message directly.
  *

subsys/zbus/zbus.c

@@ -122,6 +122,26 @@ const struct zbus_channel *zbus_chan_from_id(uint32_t channel_id)
 
 #endif /* CONFIG_ZBUS_CHANNEL_ID */
 
+#if defined(CONFIG_ZBUS_CHANNEL_NAME)
+
+const struct zbus_channel *zbus_chan_from_name(const char *name)
+{
+	if (!name) {
+		return NULL;
+	}
+
+	STRUCT_SECTION_FOREACH(zbus_channel, chan) {
+		if (strcmp(chan->name, name) == 0) {
+			/* Found matching channel */
+			return chan;
+		}
+	}
+	/* No matching channel exists */
+	return NULL;
+}
+
+#endif /* CONFIG_ZBUS_CHANNEL_NAME */
+
 static inline int _zbus_notify_observer(const struct zbus_channel *chan,
 					const struct zbus_observer *obs, k_timepoint_t end_time,
 					struct net_buf *buf)