create a C/C++ plugin system for pybullet / C-API.

2017-09-22 19:17:57 -07:00
parent b9b1b2dbca
commit 3783dccaa3
28 changed files with 1111 additions and 524 deletions
--- a/examples/SharedMemory/b3PluginManager.cpp
+++ b/examples/SharedMemory/b3PluginManager.cpp
@@ -0,0 +1,151 @@
+
+#include "b3PluginManager.h"
+#include "Bullet3Common/b3HashMap.h"
+#include "Bullet3Common/b3ResizablePool.h"
+#include "plugins/b3PluginAPI.h"
+#include "SharedMemoryPublic.h"
+
+#ifdef _WIN32
+    #define WIN32_LEAN_AND_MEAN
+    #define VC_EXTRALEAN
+    #include <windows.h>
+
+    typedef HMODULE             B3_DYNLIB_HANDLE;
+
+    #define B3_DYNLIB_OPEN    LoadLibrary
+    #define B3_DYNLIB_CLOSE   FreeLibrary
+    #define B3_DYNLIB_IMPORT  GetProcAddress
+#else
+    #include <dlfcn.h>
+    
+    typedef void*                   B3_DYNLIB_HANDLE;
+
+    #define B3_DYNLIB_OPEN(path)  dlopen(path, RTLD_NOW | RTLD_GLOBAL)
+    #define B3_DYNLIB_CLOSE       dlclose
+    #define B3_DYNLIB_IMPORT      dlsym
+#endif
+
+struct b3Plugin
+{
+	B3_DYNLIB_HANDLE m_pluginHandle;
+	std::string m_pluginPath;
+
+	PFN_INIT m_initFunc;
+	PFN_EXIT m_exitFunc;
+	PFN_EXECUTE m_executeCommandFunc;
+
+	void clear()
+	{
+		B3_DYNLIB_CLOSE(m_pluginHandle);
+		m_pluginHandle = 0;
+		m_initFunc = 0;
+		m_exitFunc = 0;
+		m_executeCommandFunc = 0;
+	}
+};
+
+typedef b3PoolBodyHandle<b3Plugin> b3PluginHandle;
+
+struct b3PluginManagerInternalData
+{
+	b3ResizablePool<b3PluginHandle> m_plugins;
+	b3HashMap<b3HashString, b3PluginHandle> m_pluginMap;
+};
+
+b3PluginManager::b3PluginManager()
+{
+	m_data = new b3PluginManagerInternalData;
+}
+
+b3PluginManager::~b3PluginManager()
+{
+	m_data->m_pluginMap.clear();
+	m_data->m_plugins.exitHandles();
+	delete m_data;
+}
+		
+int b3PluginManager::loadPlugin(const char* pluginPath)
+{
+	int pluginUniqueId = -1;
+
+	b3Plugin* plugin = m_data->m_pluginMap.find(pluginPath);
+	if (plugin)
+	{
+		//already loaded
+	}
+	else
+	{
+		pluginUniqueId = m_data->m_plugins.allocHandle();
+		b3PluginHandle* plugin = m_data->m_plugins.getHandle(pluginUniqueId);
+
+		B3_DYNLIB_HANDLE pluginHandle = B3_DYNLIB_OPEN(pluginPath);
+		bool ok = false;
+		if (pluginHandle)
+		{
+
+			plugin->m_initFunc = (PFN_INIT)B3_DYNLIB_IMPORT(pluginHandle, "initPlugin");
+			plugin->m_exitFunc = (PFN_EXIT)B3_DYNLIB_IMPORT(pluginHandle, "exitPlugin");
+			plugin->m_executeCommandFunc = (PFN_EXECUTE)B3_DYNLIB_IMPORT(pluginHandle, "executePluginCommand");
+
+			if (plugin->m_initFunc && plugin->m_exitFunc && plugin->m_executeCommandFunc)
+			{
+				int version = plugin->m_initFunc();
+				if (version == SHARED_MEMORY_MAGIC_NUMBER)
+				{
+					ok = true;
+					plugin->m_pluginHandle = pluginHandle;
+					plugin->m_pluginPath = pluginPath;
+					m_data->m_pluginMap.insert(pluginPath, *plugin);
+				}
+				else
+				{
+					int expect = SHARED_MEMORY_MAGIC_NUMBER;
+					b3Warning("Warning: plugin is wrong version: expected %d, got %d\n", expect, version);
+				}
+			}
+			else
+			{
+				b3Warning("Loaded plugin but couldn't bind functions");
+			}
+
+			if (!ok)
+			{
+				B3_DYNLIB_CLOSE(pluginHandle);
+			}
+		}
+		else
+		{
+			b3Warning("Warning: couldn't load plugin %s\n", pluginPath);
+		}
+		if (!ok)
+		{
+			m_data->m_plugins.freeHandle(pluginUniqueId);
+			pluginUniqueId = -1;
+		}
+	}
+	return pluginUniqueId;
+}
+
+void b3PluginManager::unloadPlugin(int pluginUniqueId)
+{
+	b3PluginHandle* plugin = m_data->m_plugins.getHandle(pluginUniqueId);
+	if (plugin)
+	{
+		plugin->m_exitFunc();
+		m_data->m_pluginMap.remove(plugin->m_pluginPath.c_str());
+		m_data->m_plugins.freeHandle(pluginUniqueId);
+	}
+}
+		
+
+int b3PluginManager::executePluginCommand(int pluginUniqueId, const char* arguments)
+{
+	int result = -1;
+
+	b3PluginHandle* plugin = m_data->m_plugins.getHandle(pluginUniqueId);
+	if (plugin)
+	{
+		result = plugin->m_executeCommandFunc();
+	}
+	return result;
+}