audacia/src/LoadModules.cpp

319 lines
8.2 KiB
C++

/**********************************************************************
Audacity: A Digital Audio Editor
LoadModules.cpp
Dominic Mazzoni
James Crook
*******************************************************************//*!
\file LoadModules.cpp
\brief Based on LoadLadspa, this code loads pluggable Audacity
extension modules. It also has the code to (a) invoke a script
server and (b) invoke a function returning a replacement window,
i.e. an alternative to the usual interface, for Audacity.
*//*******************************************************************/
#include <wx/dynlib.h>
#include <wx/list.h>
#include <wx/log.h>
#include <wx/string.h>
#include "Audacity.h"
#include "AudacityApp.h"
#include "Internat.h"
#include "commands/ScriptCommandRelay.h"
#include <NonGuiThread.h> // header from libwidgetextra
#include "LoadModules.h"
#define initFnName "ExtensionModuleInit"
#define versionFnName "GetVersionString"
#define scriptFnName "RegScriptServerFunc"
#define mainPanelFnName "MainPanelFunc"
typedef wxWindow * pwxWindow;
typedef int (*tModuleInit)(int);
typedef wxString (*tVersionFn)();
typedef pwxWindow (*tPanelFn)(int);
// This variable will hold the address of a subroutine in
// a DLL that can hijack the normal panel.
tPanelFn pPanelHijack=NULL;
// Next two commented out lines are handy when investigating
// strange DLL behaviour. Instead of dynamic linking,
// link the library which has the replacement panel statically.
// Give the address of the routine here.
// This is a great help in identifying missing
// symbols which otherwise cause a dll to unload after loading
// without an explanation as to why!
//extern wxWindow * MainPanelFunc( int i );
//tPanelFn pPanelHijack=&MainPanelFunc;
/// IF pPanelHijack has been found in a module DLL
/// THEN when this function is called we'll go and
/// create that window instead of the normal one.
wxWindow * MakeHijackPanel()
{
if( pPanelHijack == NULL )
return NULL;
return pPanelHijack(0);
}
// This variable will hold the address of a subroutine in a DLL that
// starts a thread and reads script commands.
tpRegScriptServerFunc scriptFn;
void LoadModule(wxString fname)
{
wxLogDebug(wxT("About to load module %s"), fname.c_str());
tModuleInit mainFn = NULL;
#if defined(__WXMAC__)
wxLogNull logNo;
#endif
// As a courtesy to some modules that might be bridges to
// open other modules, we set the current working
// directory to be the module's directory.
wxString saveOldCWD = ::wxGetCwd();
wxString prefix = ::wxPathOnly(fname);
::wxSetWorkingDirectory(prefix);
wxDynamicLibrary* pDLL = new wxDynamicLibrary();
if (pDLL && pDLL->Load(fname, wxDL_LAZY))
{
int result = 1;
mainFn = (tModuleInit)(pDLL->GetSymbol(wxT(initFnName)));
if (mainFn)
result = mainFn( 0 );
// If the module provides a version string, check that it matches the
// Audacity version string. (For now, they must match exactly)
// For compatibility reasons, if no version string is provided we try to
// load the module anyway.
tVersionFn versionFn = (tVersionFn)(pDLL->GetSymbol(wxT(versionFnName)));
if (versionFn)
{
wxString moduleVersion = versionFn();
if (!moduleVersion.IsSameAs(AUDACITY_VERSION_STRING))
{
wxLogError(wxT("The module %s is designed to work with Audacity version %s; it will not be loaded."), fname.c_str(), moduleVersion.c_str());
delete pDLL;
return;
}
}
else
{
wxLogWarning(wxT("The module %s does not provide a version string. Attempting to load it anyway."), fname.c_str());
}
if(( scriptFn == NULL ) &&(result>=0 ))
scriptFn = (tpRegScriptServerFunc)(pDLL->GetSymbol(wxT(scriptFnName)));
if((pPanelHijack==NULL ) && (result>=0))
pPanelHijack = (tPanelFn)(pDLL->GetSymbol(wxT(mainPanelFnName)));
}
::wxSetWorkingDirectory(saveOldCWD);
}
void LoadModules(CommandHandler &cmdHandler)
{
wxArrayString audacityPathList = wxGetApp().audacityPathList;
wxArrayString pathList;
wxArrayString files;
wxString pathVar;
unsigned int i;
#if 0
// Code from LoadLadspa that might be useful in load modules.
pathVar = wxGetenv(wxT("AUDACITY_MODULES_PATH"));
if (pathVar != wxT(""))
wxGetApp().AddMultiPathsToPathList(pathVar, pathList);
#ifdef __WXGTK__
wxGetApp().AddUniquePathToPathList(INSTALL_PREFIX wxT("/modules"), pathList);
wxGetApp().AddUniquePathToPathList(wxT("/usr/local/lib/modules"), pathList);
wxGetApp().AddUniquePathToPathList(wxT("/usr/lib/modules"), pathList);
#endif
#endif
for(i=0; i<audacityPathList.GetCount(); i++) {
wxString prefix = audacityPathList[i] + wxFILE_SEP_PATH;
wxGetApp().AddUniquePathToPathList(prefix + wxT("modules"),
pathList);
}
#ifdef __WXMSW__
wxGetApp().FindFilesInPathList(wxT("*.dll"), pathList, files);
#else
wxGetApp().FindFilesInPathList(wxT("*.so"), pathList, files);
#endif
for(i=0; i<files.GetCount(); i++)
LoadModule(files[i]);
// After loading all the modules, we may have a registered scripting function.
if(scriptFn)
{
ScriptCommandRelay::SetCommandHandler(cmdHandler);
ScriptCommandRelay::SetRegScriptServerFunc(scriptFn);
NonGuiThread::StartChild(&ScriptCommandRelay::Run);
}
}
Module::Module(const wxString & name)
{
mName = name;
mLib = new wxDynamicLibrary();
mDispatch = NULL;
}
Module::~Module()
{
delete mLib;
}
bool Module::Load()
{
wxLogNull logNo;
if (mLib->IsLoaded()) {
if (mDispatch) {
return true;
}
return false;
}
if (!mLib->Load(mName, wxDL_LAZY)) {
return false;
}
mDispatch = (fnModuleDispatch) mLib->GetSymbol(wxT(ModuleDispatchName));
if (!mDispatch) {
return false;
}
bool res = ((mDispatch(ModuleInitialize))!=0);
if (res) {
return true;
}
mDispatch = NULL;
return false;
}
void Module::Unload()
{
if (mLib->IsLoaded()) {
mDispatch(ModuleTerminate);
}
mLib->Unload();
}
int Module::Dispatch(ModuleDispatchTypes type)
{
if (mLib->IsLoaded()) {
return mDispatch(type);
}
return 0;
}
//
// Module Manager (using wxPluginManager would be MUCH better)
//
ModuleManager *ModuleManager::mInstance;
bool ModuleManager::OnInit()
{
mInstance = this;
return true;
}
void ModuleManager::OnExit()
{
size_t cnt = mModules.GetCount();
for (size_t ndx = 0; ndx < cnt; ndx++) {
delete (Module *) mModules[ndx];
}
mModules.Clear();
}
void ModuleManager::Initialize()
{
wxArrayString audacityPathList = wxGetApp().audacityPathList;
wxArrayString pathList;
wxArrayString files;
wxString pathVar;
size_t i;
// Code from LoadLadspa that might be useful in load modules.
pathVar = wxGetenv(wxT("AUDACITY_MODULES_PATH"));
if (pathVar != wxT("")) {
wxGetApp().AddMultiPathsToPathList(pathVar, pathList);
}
for (i = 0; i < audacityPathList.GetCount(); i++) {
wxString prefix = audacityPathList[i] + wxFILE_SEP_PATH;
wxGetApp().AddUniquePathToPathList(prefix + wxT("modules"),
pathList);
}
#if defined(__WXMSW__)
wxGetApp().FindFilesInPathList(wxT("*.dll"), pathList, files);
// #elif defined(__WXMAC__)
// wxGetApp().FindFilesInPathList(wxT("*.dylib"), pathList, files);
#else
wxGetApp().FindFilesInPathList(wxT("*.so"), pathList, files);
#endif
for (i = 0; i < files.GetCount(); i++) {
Module *module = new Module(files[i]);
if (module->Load()) {
mInstance->mModules.Add(module);
}
else {
delete module;
}
}
}
int ModuleManager::Dispatch(ModuleDispatchTypes type)
{
size_t cnt = mInstance->mModules.GetCount();
for (size_t ndx = 0; ndx < cnt; ndx++) {
Module *module = (Module *)mInstance->mModules[ndx];
module->Dispatch(type);
}
return 0;
}
IMPLEMENT_DYNAMIC_CLASS(ModuleManager, wxModule);
// Indentation settings for Vim and Emacs and unique identifier for Arch, a
// version control system. Please do not modify past this point.
//
// Local Variables:
// c-basic-offset: 3
// indent-tabs-mode: nil
// End:
//
// vim: et sts=3 sw=3