feat: Added message buffer releasing

app/src/incphub/include/incphub/incphub_client.h

@@ -28,6 +28,12 @@ int incphub_init_client(incphub_cli_t **cli, ntl_port_t port);
 /// @return INCPHUB_OK on success, an error otherwise
 int incphub_get_msg_buffer(incphub_cli_t *cli, uint8_t **buffer_ptr, size_t length);
 
+/// @brief Releases a buffer previously acquired with incphub_get_msg_buffer
+/// @param cli Current client handle
+/// @param buffer The buffer to release
+/// @return INCPHUB_OK on success, an error otherwise
+int incphub_release_msg_buffer(incphub_cli_t *cli, uint8_t *buffer);
+
 /// @brief Attempts to send a message to the local interface
 /// @param cli Current client handle
 /// @param buffer The message buffer

app/src/incphub/src/incphub_client.c

@@ -42,6 +42,23 @@ int incphub_get_msg_buffer(incphub_cli_t *cli, uint8_t **buffer_ptr, size_t leng
 	return INCPHUB_OK;
 }
 
+int incphub_release_msg_buffer(incphub_cli_t *cli, uint8_t *buffer)
+{
+	if (cli == NULL)
+		return INCPHUB_EINVAL;
+	if (buffer == NULL)
+		return INCPHUB_EINVAL;
+
+	// cli requested for interface consistency only (for now)
+	(void)cli;
+
+	// Unwind buffer pointer
+	uint8_t *unwound = buffer - sizeof(nil_header_t) + sizeof(ntl_header_t);
+
+	// Release correct buffer pointer
+	return release_msg_buffer(buffer);
+}
+
 int incphub_send_local(incphub_cli_t *cli, uint8_t *buffer, size_t length, ntl_port_t dst_port)
 {
 	if (cli == NULL)

app/src/incphub/src/incphub_shared.c

@@ -38,6 +38,8 @@ static incphub_cli_t *find_empty_client();
 static incphub_cli_t *find_client_with_port(ntl_port_t port);
 /// @remark Returns NULL if not found
 static uint8_t *find_unused_buffer();
+/// @remark Returns -1 if not found
+static int find_index_of_buffer(uint8_t *buffer);
 
 
 
@@ -111,6 +113,38 @@ int get_msg_buffer(uint8_t **buffer_ptr, size_t len)
     return INCPHUB_OK;
 }
 
+int release_msg_buffer(uint8_t *buffer)
+{
+    if (buffer == NULL)
+        return INCPHUB_EINVAL;
+
+    // == Enter ==
+    if (!global_lock(portMAX_DELAY))
+        return INCPHUB_EAGAIN;
+
+    int index = find_index_of_buffer(buffer);
+
+    // Handle invalid buffers
+    if (index == -1)
+    {
+        global_unlock();
+        return INCPHUB_EINVAL;
+    }
+
+    // Handle not-in-use buffers
+    if (_msg_buffer_used[index] == false)
+    {
+        global_unlock();
+        return INCPHUB_EINVAL;
+    }
+
+    // Mark buffer as free
+    _msg_buffer_used[index] = false;
+
+    global_unlock();
+    return INCPHUB_OK;
+}
+
 int get_client_with_port(ntl_port_t port, incphub_cli_t **client_ptr)
 {
     if (port == NTL_PORT_EMPTY)
@@ -195,3 +229,14 @@ static uint8_t *find_unused_buffer()
 
     return NULL;
 }
+
+static int find_index_of_buffer(uint8_t *buffer)
+{
+    for (int i = 0; i < INCPHUB_MSG_BUFFER_COUNT; ++i)
+    {
+        if (buffer = _msg_buffers[i])
+            return i;
+    }
+
+    return -1;
+}

app/src/incphub/src/incphub_shared.h

@@ -46,6 +46,11 @@ int register_client(incphub_cli_t **cli_ptr, ntl_port_t port, TaskHandle_t task)
 /// @return INCPHUB_OK on success, an error otherwise
 int get_msg_buffer(uint8_t **buffer_ptr, size_t len);
 
+/// @brief Releases a buffer previously acquired with get_msg_buffer
+/// @param buffer The buffer to release
+/// @return INCPHUB_OK on success, an error otherwise
+int release_msg_buffer(uint8_t *buffer);
+
 /// @brief Attempts to get the client assigned to the given port
 /// @param port The port to look for
 /// @param client_ptr Location to return the client