comparison vamp-hostsdk/host-c.h @ 393:632c662e95e7 vh

Small test program & some changes to support it

 */
 
 /*
     This file defines a low-level API for enumerating and loading
     plugin libraries using C calling conventions. It could be used in
-    C programs or in languages with C-compatible foreign-function
-    interfaces.
+    C programs, or in languages with C-compatible foreign-function
+    interfaces. Note that this works by calling to the C++ Vamp host
+    SDK, so any program using this interface must still link against
+    the rest of the Vamp plugin library and the C++ standard library.
 
     This is not the simplest or easiest interface for hosting Vamp
     plugins -- if you have the capability to use the C++ API, please
     do that instead. (Most programs should not even include this
     header.)

     string) plus a method to load a single plugin based on its key
     (obtaining an instance of class Plugin). With the C++ interface
     you go straight from the key to a live instance of the plugin. The
     PluginLoader also provides various facilities to adapt the plugin
     based on your requirements (e.g. to do time- to frequency-domain
-    conversion for its input).
+    conversion for you if the plugin requires it).
 
     This low-level C interface, on the other hand, deals only in
     plugin libraries and static descriptors, not in plugin
     instances. You can enumerate the installed libraries, getting just
     the base .soname of each library. Then you can retrieve each of
     the raw C plugin descriptors from a library, and use the
     descriptor (whose interface is defined in vamp/vamp.h) to
-    instantiate the plugin. So this header corresponds to the first
-    part of the PluginLoader class interface (finding and loading
-    plugin libraries and retrieving plugin descriptors from them) but
-    does not do any of the rest (instantiating and adapting the
-    plugins themselves), which may mean the resulting plugin is
-    relatively hard to use compared to that provided by the
-    PluginLoader API.
+    instantiate the plugin.
+
+    So this header corresponds to the first part of the PluginLoader
+    class interface: finding and loading plugin libraries and
+    retrieving plugin descriptors from them. But it does not do any of
+    the rest, i.e. instantiating and adapting the plugins themselves.
+    Although this makes the API appear very simple, it means the
+    resulting plugins are relatively hard to use compared to those
+    obtained by the PluginLoader API. There is no way to get to the
+    full C++ abstraction using this API.
 
     This API is not thread-safe; use it from a single application
     thread, or guard access to it with a mutex.
 
     This header was introduced in version 2.6 of the Vamp plugin SDK.

  * index, in the range 0..(vhGetLibraryCount()-1).
  */
 extern const char *vhGetLibraryName(int library);
 
 /**
- * Load a plugin library given its library name, that is, the base
- * soname as returned by vhGetLibraryName. If the library cannot be
+ * Return the library index for the given library name, or -1 if the
+ * name is not known.
+ */
+extern int vhGetLibraryIndex(const char *name);
+    
+/**
+ * Load the library with the given index. If the library cannot be
  * loaded for any reason, the return value is 0; otherwise it is an
  * opaque pointer suitable for passing to other functions in this API.
  */
-extern vhLibrary vhLoadLibrary(const char *libraryName);
+extern vhLibrary vhLoadLibrary(int library);
 
 /**
  * Return the number of Vamp plugins in the given library.
  */
 extern int vhGetPluginCount(vhLibrary library);
 
 /**
  * Return a Vamp plugin descriptor for a plugin in a given
- * library. (This simply calls the vampGetPluginDescriptor function in
- * that library with the given plugin index and returns the result.)
+ * library. This simply calls the vampGetPluginDescriptor function in
+ * that library with the given plugin index and returns the
+ * result. See vamp/vamp.h for details about the plugin descriptor.
  */ 
 extern const VampPluginDescriptor *vhGetPluginDescriptor(vhLibrary library,
 							 int plugin);
 
 /**