audacia/src/LoadModules.cpp

296 lines
8.6 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/msgdlg.h>
#include <wx/string.h>
#include <wx/filename.h>
#include "Audacity.h"
#include "AudacityApp.h"
#include "Internat.h"
#include "commands/ScriptCommandRelay.h"
#include <NonGuiThread.h> // header from libwidgetextra
#ifdef EXPERIMENTAL_MODULE_PREFS
#include "Prefs.h"
#endif
#include "LoadModules.h"
#include "widgets/MultiDialog.h"
#define initFnName "ExtensionModuleInit"
#define versionFnName "GetVersionString"
#define scriptFnName "RegScriptServerFunc"
#define mainPanelFnName "MainPanelFunc"
typedef wxWindow * pwxWindow;
typedef int (*tModuleInit)(int);
//typedef wxString (*tVersionFn)();
typedef wxChar * (*tVersionFn)();
typedef pwxWindow (*tPanelFn)(int);
// This variable will hold the address of a subroutine in
// a DLL that can hijack the normal panel.
static 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.
static tpRegScriptServerFunc scriptFn;
#ifdef EXPERIMENTAL_MODULE_PREFS
bool IsAllowedModule( wxString fname )
{
bool bLoad = false;
wxString ShortName = wxFileName( fname ).GetName();
if( (ShortName.CmpNoCase( wxT("mod-script-pipe")) == 0 ))
{
gPrefs->Read(wxT("/Module/mod-script-pipe"), &bLoad, false);
}
else if( (ShortName.CmpNoCase( wxT("mod-nyq-bench")) == 0 ))
{
gPrefs->Read(wxT("/Module/mod-nyq-bench"), &bLoad, false);
}
else if( (ShortName.CmpNoCase( wxT("mod-track-panel")) == 0 ))
{
gPrefs->Read(wxT("/Module/mod-track-panel"), &bLoad, false);
}
return bLoad;
}
#endif // EXPERIMENTAL_MODULE_PREFS
Module::Module(const wxString & name)
{
mName = name;
mLib = new wxDynamicLibrary();
mDispatch = NULL;
}
Module::~Module()
{
delete mLib;
}
bool Module::Load()
{
if (mLib->IsLoaded()) {
if (mDispatch) {
return true;
}
return false;
}
if (!mLib->Load(mName, wxDL_LAZY)) {
return false;
}
// Check version string matches. (For now, they must match exactly)
tVersionFn versionFn = (tVersionFn)(mLib->GetSymbol(wxT(versionFnName)));
if (versionFn == NULL){
wxString ShortName = wxFileName( mName ).GetName();
wxMessageBox(wxString::Format(_("The module %s does not provide a version string.\nIt will not be loaded."), ShortName.c_str()), _("Module Unsuitable"));
wxLogMessage(wxString::Format(_("The module %s does not provide a version string. It will not be loaded."), mName.c_str()));
mLib->Unload();
return false;
}
wxString moduleVersion = versionFn();
if( !moduleVersion.IsSameAs(AUDACITY_VERSION_STRING)) {
wxString ShortName = wxFileName( mName ).GetName();
wxMessageBox(wxString::Format(_("The module %s is matched with Audacity version %s.\n\nIt will not be loaded."), ShortName.c_str(), moduleVersion.c_str()), _("Module Unsuitable"));
wxLogMessage(wxString::Format(_("The module %s is matched with Audacity version %s. It will not be loaded."), mName.c_str(), moduleVersion.c_str()));
mLib->Unload();
return false;
}
mDispatch = (fnModuleDispatch) mLib->GetSymbol(wxT(ModuleDispatchName));
if (!mDispatch) {
// Module does not provide a dispatch function...
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;
}
void * Module::GetSymbol(wxString name)
{
return mLib->GetSymbol(name);
}
//
// Module Manager
//
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(CommandHandler &cmdHandler)
{
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);
#else
wxGetApp().FindFilesInPathList(wxT("*.so"), pathList, files);
#endif
for (i = 0; i < files.GetCount(); i++) {
// 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(files[i]);
::wxSetWorkingDirectory(prefix);
#ifdef EXPERIMENTAL_MODULE_PREFS
if( !IsAllowedModule( files[i] ) ) // don't try and check the in-date-ness before this as that means loading the module to call it's GetVersionString, which could do anything.
#endif
{
wxString ShortName = wxFileName( files[i] ).GetName();
wxString msg;
msg.Printf(_("Module \"%s\" found."), ShortName.c_str());
msg += _("\n\nOnly use modules from trusted sources");
const wxChar *buttons[] = {_("Yes"), _("No"), NULL}; // could add a button here for 'yes and remember that', and put it into the cfg file. Needs more thought.
int action;
action = ShowMultiDialog(msg, _("Module Loader"), buttons, _("Try and load this module?"), false);
if(action == 1) // "No"
continue;
}
Module *module = new Module(files[i]);
if (module->Load()) // it will get rejected if there are version problems
{
mInstance->mModules.Add(module);
// We've loaded and initialised OK.
// So look for special case functions:
wxLogNull logNo; // Don't show wxWidgets errors if we can't do these. (Was: Fix bug 544.)
// (a) for scripting.
if( scriptFn == NULL )
scriptFn = (tpRegScriptServerFunc)(module->GetSymbol(wxT(scriptFnName)));
// (b) for hijacking the entire Audacity panel.
if( pPanelHijack==NULL )
{
pPanelHijack = (tPanelFn)(module->GetSymbol(wxT(mainPanelFnName)));
}
}
else {
delete module;
}
::wxSetWorkingDirectory(saveOldCWD);
}
// After loading all the modules, we may have a registered scripting function.
if(scriptFn)
{
ScriptCommandRelay::SetCommandHandler(cmdHandler);
ScriptCommandRelay::SetRegScriptServerFunc(scriptFn);
NonGuiThread::StartChild(&ScriptCommandRelay::Run);
}
}
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);