Clean up and improve documentation (#156)

* Clean up documentation

Signed-off-by: ahcorde <ahcorde@gmail.com>

* Added extra space between brief and params

Signed-off-by: ahcorde <ahcorde@gmail.com>

Author: ahcorde

include/class_loader/class_loader.hpp

@@ -59,25 +59,22 @@
 namespace class_loader
 {
 
-/// Returns the default library prefix for the native os
-CLASS_LOADER_PUBLIC
-std::string systemLibraryPrefix();
-
-/// Returns runtime library extension for native os
-CLASS_LOADER_PUBLIC
-std::string systemLibrarySuffix();
-
 /// Returns a platform specific version of a basic library name
 /**
  * On *nix platforms the library name is prefixed with `lib`.
  * On all platforms the output of class_loader::systemLibrarySuffix() is appended.
+ *
+ * @param[in] library_name name to add the prefix
+ * @return library name with the prefix added
  */
 CLASS_LOADER_PUBLIC
 std::string systemLibraryFormat(const std::string & library_name);
 
 /**
  * @class ClassLoader
- * @brief This class allows loading and unloading of dynamically linked libraries which contain class definitions from which objects can be created/destroyed during runtime (i.e. class_loader). Libraries loaded by a ClassLoader are only accessible within scope of that ClassLoader object.
+ * @brief This class allows loading and unloading of dynamically linked libraries which contain class
+ * definitions from which objects can be created/destroyed during runtime (i.e. class_loader).
+ * Libraries loaded by a ClassLoader are only accessible within scope of that ClassLoader object.
  */
 class ClassLoader
 {
@@ -89,21 +86,24 @@ class ClassLoader
   using UniquePtr = std::unique_ptr<Base, DeleterType<Base>>;
 
   /**
-   * @brief  Constructor for ClassLoader
+   * @brief Constructor for ClassLoader
+   *
    * @param library_path - The path of the runtime library to load
-   * @param ondemand_load_unload - Indicates if on-demand (lazy) unloading/loading of libraries occurs as plugins are created/destroyed
+   * @param ondemand_load_unload - Indicates if on-demand (lazy) unloading/loading of libraries
+   * occurs as plugins are created/destroyed.
    */
   CLASS_LOADER_PUBLIC
   explicit ClassLoader(const std::string & library_path, bool ondemand_load_unload = false);
 
   /**
-   * @brief  Destructor for ClassLoader. All libraries opened by this ClassLoader are unloaded automatically.
+   * @brief Destructor for ClassLoader. All libraries opened by this ClassLoader are unloaded automatically.
    */
   CLASS_LOADER_PUBLIC
   virtual ~ClassLoader();
 
   /**
-   * @brief  Indicates which classes (i.e. class_loader) that can be loaded by this object
+   * @brief Indicates which classes (i.e. class_loader) that can be loaded by this object
+   *
    * @return vector of strings indicating names of instantiable classes derived from <Base>
    */
   template<class Base>
@@ -113,12 +113,12 @@ class ClassLoader
   }
 
   /**
-   * @brief  Generates an instance of loadable classes (i.e. class_loader).
+   * @brief Generates an instance of loadable classes (i.e. class_loader).
    *
    * It is not necessary for the user to call loadLibrary() as it will be invoked automatically
    * if the library is not yet loaded (which typically happens when in "On Demand Load/Unload" mode).
    *
-   * @param  derived_class_name The name of the class we want to create (@see getAvailableClasses())
+   * @param derived_class_name The name of the class we want to create (@see getAvailableClasses())
    * @return A std::shared_ptr<Base> to newly created plugin object
    */
   template<class Base>
@@ -174,6 +174,7 @@ class ClassLoader
 
   /**
    * @brief Indicates if a plugin class is available
+   *
    * @param Base - polymorphic type indicating base class
    * @param class_name - the name of the plugin class
    * @return true if yes it is available, false otherwise
@@ -188,40 +189,64 @@ class ClassLoader
 
   /**
    * @brief Gets the full-qualified path and name of the library associated with this class loader
+   *
+   * @return the full-qualified path and name of the library
    */
   CLASS_LOADER_PUBLIC
   const std::string & getLibraryPath() const;
 
   /**
-   * @brief  Indicates if a library is loaded within the scope of this ClassLoader. Note that the library may already be loaded internally through another ClassLoader, but until loadLibrary() method is called, the ClassLoader cannot create objects from said library. If we want to see if the library has been opened by somebody else, @see isLibraryLoadedByAnyClassloader()
-   * @param  library_path The path to the library to load
+   * @brief Indicates if a library is loaded within the scope of this ClassLoader.
+   *
+   * Note that the library may already be loaded internally through another ClassLoader,
+   * but until loadLibrary() method is called, the ClassLoader cannot create objects from said library.
+   * If we want to see if the library has been opened by somebody else, @see isLibraryLoadedByAnyClassloader()
+   *
+   * @param library_path The path to the library to load
    * @return true if library is loaded within this ClassLoader object's scope, otherwise false
    */
   CLASS_LOADER_PUBLIC
   bool isLibraryLoaded() const;
 
   /**
-   * @brief  Indicates if a library is loaded by some entity in the plugin system (another ClassLoader), but not necessarily loaded by this ClassLoader
+   * @brief Indicates if a library is loaded by some entity in the plugin system (another ClassLoader),
+   * but not necessarily loaded by this ClassLoader.
+   *
    * @return true if library is loaded within the scope of the plugin system, otherwise false
    */
   CLASS_LOADER_PUBLIC
   bool isLibraryLoadedByAnyClassloader() const;
 
   /**
-   * @brief Indicates if the library is to be loaded/unloaded on demand...meaning that only to load a lib when the first plugin is created and automatically shut it down when last active plugin is destroyed.
+   * @brief Indicates if the library is to be loaded/unloaded on demand...meaning that only to load
+   * a lib when the first plugin is created and automatically shut it down when last active plugin
+   * is destroyed.
+   *
+   * @return true if ondemand load and unload is active, otherwise false
    */
   CLASS_LOADER_PUBLIC
   bool isOnDemandLoadUnloadEnabled() const;
 
   /**
-   * @brief  Attempts to load a library on behalf of the ClassLoader. If the library is already opened, this method has no effect. If the library has been already opened by some other entity (i.e. another ClassLoader or global interface), this object is given permissions to access any plugin classes loaded by that other entity. This is
-   * @param  library_path The path to the library to load
+   * @brief  Attempts to load a library on behalf of the ClassLoader. If the library is already
+   * opened, this method has no effect. If the library has been already opened by some other entity
+   * (i.e. another ClassLoader or global interface), this object is given permissions to access any
+   * plugin classes loaded by that other entity.
    */
   CLASS_LOADER_PUBLIC
   void loadLibrary();
 
   /**
-   * @brief  Attempts to unload a library loaded within scope of the ClassLoader. If the library is not opened, this method has no effect. If the library is opened by other another ClassLoader, the library will NOT be unloaded internally -- however this ClassLoader will no longer be able to instantiate class_loader bound to that library. If there are plugin objects that exist in memory created by this classloader, a warning message will appear and the library will not be unloaded. If loadLibrary() was called multiple times (e.g. in the case of multiple threads or purposefully in a single thread), the user is responsible for calling unloadLibrary() the same number of times. The library will not be unloaded within the context of this classloader until the number of unload calls matches the number of loads.
+   * @brief  Attempts to unload a library loaded within scope of the ClassLoader. If the library is
+   * not opened, this method has no effect. If the library is opened by other another ClassLoader,
+   * the library will NOT be unloaded internally -- however this ClassLoader will no longer be able
+   * to instantiate class_loader bound to that library. If there are plugin objects that exist in
+   * memory created by this classloader, a warning message will appear and the library will not be
+   * unloaded. If loadLibrary() was called multiple times (e.g. in the case of multiple threads or
+   * purposefully in a single thread), the user is responsible for calling unloadLibrary() the same
+   * number of times. The library will not be unloaded within the context of this classloader until
+   * the number of unload calls matches the number of loads.
+   *
    * @return The number of times more unloadLibrary() has to be called for it to be unbound from this ClassLoader
    */
   CLASS_LOADER_PUBLIC
@@ -230,6 +255,7 @@ class ClassLoader
 private:
   /**
    * @brief Callback method when a plugin created by this class loader is destroyed
+   *
    * @param obj - A pointer to the deleted object
    */
   template<class Base>
@@ -319,9 +345,14 @@ class ClassLoader
   static void setUnmanagedInstanceBeenCreated(bool state);
 
   /**
-   * @brief As the library may be unloaded in "on-demand load/unload" mode, unload maybe called from createInstance(). The problem is that createInstance() locks the plugin_ref_count as does unloadLibrary(). This method is the implementation of unloadLibrary but with a parameter to decide if plugin_ref_mutex_ should be locked
+   * @brief As the library may be unloaded in "on-demand load/unload" mode, unload maybe called from
+   * createInstance(). The problem is that createInstance() locks the plugin_ref_count as does
+   * unloadLibrary(). This method is the implementation of unloadLibrary but with a parameter to
+   * decide if plugin_ref_mutex_ should be locked.
+   *
    * @param lock_plugin_ref_count - Set to true if plugin_ref_count_mutex_ should be locked, else false
-   * @return The number of times unloadLibraryInternal has to be called again for it to be unbound from this ClassLoader
+   * @return The number of times unloadLibraryInternal has to be called again for it to be unbound
+   *   from this ClassLoader
    */
   CLASS_LOADER_PUBLIC
   int unloadLibraryInternal(bool lock_plugin_ref_count);