control_protocol_manager.cc

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/*
    Copyright (C) 2000-2007 Paul Davis

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <glibmm/module.h>

#include <glibmm/fileutils.h>

#include "pbd/compose.h"
#include "pbd/file_utils.h"
#include "pbd/error.h"

#include "control_protocol/control_protocol.h"

#include "ardour/debug.h"
#include "ardour/control_protocol_manager.h"

#include "ardour/search_paths.h"


using namespace ARDOUR;
using namespace std;
using namespace PBD;

#include "i18n.h"

ControlProtocolManager* ControlProtocolManager::_instance = 0;
const string ControlProtocolManager::state_node_name = X_("ControlProtocols");

ControlProtocolManager::ControlProtocolManager ()
{
}

ControlProtocolManager::~ControlProtocolManager()
{
        Glib::Threads::Mutex::Lock lm (protocols_lock);

        for (list<ControlProtocol*>::iterator i = control_protocols.begin(); i != control_protocols.end(); ++i) {
                delete (*i);
        }

        control_protocols.clear ();


        for (list<ControlProtocolInfo*>::iterator p = control_protocol_info.begin(); p != control_protocol_info.end(); ++p) {
                delete (*p);
        }

        control_protocol_info.clear();
}

void
ControlProtocolManager::set_session (Session* s)
{
        SessionHandlePtr::set_session (s);

        if (_session) {
                Glib::Threads::Mutex::Lock lm (protocols_lock);

                for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
                        if ((*i)->requested || (*i)->mandatory) {
                                (void) activate (**i);
                        }
                }
        }
}

int
ControlProtocolManager::activate (ControlProtocolInfo& cpi)
{
        ControlProtocol* cp;

        cpi.requested = true;

        if ((cp = instantiate (cpi)) == 0) {
                return -1;
        }

        /* we split the set_state() and set_active() operations so that
           protocols that need state to configure themselves (e.g. "What device
           is connected, or supposed to be connected?") can get it before
           actually starting any interaction.
        */

        if (cpi.state) {
                /* force this by tweaking the internals of the state
                 * XMLNode. Ugh.
                 */
                cp->set_state (*cpi.state, Stateful::loading_state_version);
        } else {
                /* guarantee a call to
                   set_state() whether we have
                   existing state or not
                */
                cp->set_state (XMLNode(""), Stateful::loading_state_version);
        }

        cp->set_active (true);

        return 0;
}       

int
ControlProtocolManager::deactivate (ControlProtocolInfo& cpi)
{
        cpi.requested = false;
        return teardown (cpi);
}

void
ControlProtocolManager::session_going_away()
{
        SessionHandlePtr::session_going_away ();

        {
                Glib::Threads::Mutex::Lock lm (protocols_lock);

                for (list<ControlProtocol*>::iterator p = control_protocols.begin(); p != control_protocols.end(); ++p) {
                        delete *p;
                }

                control_protocols.clear ();

                for (list<ControlProtocolInfo*>::iterator p = control_protocol_info.begin(); p != control_protocol_info.end(); ++p) {
                        // mark existing protocols as requested
                        // otherwise the ControlProtocol instances are not recreated in set_session
                        if ((*p)->protocol) {
                                (*p)->requested = true;
                                (*p)->protocol = 0;
                        }
                }
        }
}

ControlProtocol*
ControlProtocolManager::instantiate (ControlProtocolInfo& cpi)
{
        /* CALLER MUST HOLD LOCK */

        if (_session == 0) {
                return 0;
        }

        cpi.descriptor = get_descriptor (cpi.path);

        DEBUG_TRACE (DEBUG::ControlProtocols, string_compose ("instantiating %1\n", cpi.name));

        if (cpi.descriptor == 0) {
                error << string_compose (_("control protocol name \"%1\" has no descriptor"), cpi.name) << endmsg;
                return 0;
        }

        DEBUG_TRACE (DEBUG::ControlProtocols, string_compose ("initializing %1\n", cpi.name));

        if ((cpi.protocol = cpi.descriptor->initialize (cpi.descriptor, _session)) == 0) {
                error << string_compose (_("control protocol name \"%1\" could not be initialized"), cpi.name) << endmsg;
                return 0;
        }

        control_protocols.push_back (cpi.protocol);

        ProtocolStatusChange (&cpi);

        return cpi.protocol;
}

int
ControlProtocolManager::teardown (ControlProtocolInfo& cpi)
{
        if (!cpi.protocol) {
                return 0;
        }

        if (!cpi.descriptor) {
                return 0;
        }

        if (cpi.mandatory) {
                return 0;
        }
        
        /* save current state */

        delete cpi.state;
        cpi.state = new XMLNode (cpi.protocol->get_state());
        cpi.state->add_property (X_("active"), "no");

        cpi.descriptor->destroy (cpi.descriptor, cpi.protocol);

        {
                Glib::Threads::Mutex::Lock lm (protocols_lock);
                list<ControlProtocol*>::iterator p = find (control_protocols.begin(), control_protocols.end(), cpi.protocol);
                if (p != control_protocols.end()) {
                        control_protocols.erase (p);
                } else {
                        cerr << "Programming error: ControlProtocolManager::teardown() called for " << cpi.name << ", but it was not found in control_protocols" << endl;
                }
        }

        cpi.protocol = 0;
        delete cpi.state;
        cpi.state = 0;
        delete (Glib::Module*)cpi.descriptor->module;

        ProtocolStatusChange (&cpi);

        return 0;
}

void
ControlProtocolManager::load_mandatory_protocols ()
{
        if (_session == 0) {
                return;
        }

        Glib::Threads::Mutex::Lock lm (protocols_lock);

        for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
                if ((*i)->mandatory && ((*i)->protocol == 0)) {
                        DEBUG_TRACE (DEBUG::ControlProtocols,
                                     string_compose (_("Instantiating mandatory control protocol %1"), (*i)->name));
                        instantiate (**i);
                }
        }
}

void
ControlProtocolManager::discover_control_protocols ()
{
        vector<std::string> cp_modules;

#ifdef COMPILER_MSVC

        #if defined (_DEBUG)
                Glib::PatternSpec dll_extension_pattern("*D.dll");
        #elif defined (RDC_BUILD)
                Glib::PatternSpec dll_extension_pattern("*RDC.dll");
        #elif defined (_WIN64)
                Glib::PatternSpec dll_extension_pattern("*64.dll");
        #else
                Glib::PatternSpec dll_extension_pattern("*32.dll");
        #endif
#else
        Glib::PatternSpec dll_extension_pattern("*.dll");
#endif

        Glib::PatternSpec so_extension_pattern("*.so");
        Glib::PatternSpec dylib_extension_pattern("*.dylib");

        find_files_matching_pattern (cp_modules, control_protocol_search_path (),
                                     dll_extension_pattern);

        find_files_matching_pattern (cp_modules, control_protocol_search_path (),
                                     so_extension_pattern);

        find_files_matching_pattern (cp_modules, control_protocol_search_path (),
                                     dylib_extension_pattern);

        DEBUG_TRACE (DEBUG::ControlProtocols, 
                     string_compose (_("looking for control protocols in %1\n"), control_protocol_search_path().to_string()));
        
        for (vector<std::string>::iterator i = cp_modules.begin(); i != cp_modules.end(); ++i) {
                control_protocol_discover (*i);
        }
}

int
ControlProtocolManager::control_protocol_discover (string path)
{
        ControlProtocolDescriptor* descriptor;

#ifdef __APPLE__
        /* don't load OS X shared objects that are just symlinks to the real thing.
         */

        if (path.find (".dylib") && Glib::file_test (path, Glib::FILE_TEST_IS_SYMLINK)) {
                return 0;
        }
#endif

        if ((descriptor = get_descriptor (path)) != 0) {

                if (!descriptor->probe (descriptor)) {
                        DEBUG_TRACE (DEBUG::ControlProtocols,
                                     string_compose (_("Control protocol %1 not usable"), descriptor->name));
                } else {

                        ControlProtocolInfo* cpi = new ControlProtocolInfo ();

                        cpi->descriptor = descriptor;
                        cpi->name = descriptor->name;
                        cpi->path = path;
                        cpi->protocol = 0;
                        cpi->requested = false;
                        cpi->mandatory = descriptor->mandatory;
                        cpi->supports_feedback = descriptor->supports_feedback;
                        cpi->state = 0;

                        control_protocol_info.push_back (cpi);

                        DEBUG_TRACE (DEBUG::ControlProtocols, 
                                     string_compose(_("Control surface protocol discovered: \"%1\"\n"), cpi->name));
                }

                delete (Glib::Module*)descriptor->module;
        }

        return 0;
}

ControlProtocolDescriptor*
ControlProtocolManager::get_descriptor (string path)
{
        Glib::Module* module = new Glib::Module(path);
        ControlProtocolDescriptor *descriptor = 0;
        ControlProtocolDescriptor* (*dfunc)(void);
        void* func = 0;

        if (!(*module)) {
                error << string_compose(_("ControlProtocolManager: cannot load module \"%1\" (%2)"), path, Glib::Module::get_last_error()) << endmsg;
                delete module;
                return 0;
        }

        if (!module->get_symbol("protocol_descriptor", func)) {
                error << string_compose(_("ControlProtocolManager: module \"%1\" has no descriptor function."), path) << endmsg;
                error << Glib::Module::get_last_error() << endmsg;
                delete module;
                return 0;
        }

        dfunc = (ControlProtocolDescriptor* (*)(void))func;
        descriptor = dfunc();

        if (descriptor) {
                descriptor->module = (void*)module;
        } else {
                delete module;
        }

        return descriptor;
}

void
ControlProtocolManager::foreach_known_protocol (boost::function<void(const ControlProtocolInfo*)> method)
{
        for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
                method (*i);
        }
}

ControlProtocolInfo*
ControlProtocolManager::cpi_by_name (string name)
{
        for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
                if (name == (*i)->name) {
                        return *i;
                }
        }
        return 0;
}

int
ControlProtocolManager::set_state (const XMLNode& node, int /*version*/)
{
        XMLNodeList clist;
        XMLNodeConstIterator citer;
        XMLProperty* prop;

        Glib::Threads::Mutex::Lock lm (protocols_lock);

        clist = node.children();

        for (citer = clist.begin(); citer != clist.end(); ++citer) {
                if ((*citer)->name() == X_("Protocol")) {

                        if ((prop = (*citer)->property (X_("active"))) == 0) {
                                continue;
                        }

                        bool active = string_is_affirmative (prop->value());
                        
                        if ((prop = (*citer)->property (X_("name"))) == 0) {
                                continue;
                        }

                        ControlProtocolInfo* cpi = cpi_by_name (prop->value());
                        
                        if (cpi) {
                                cpi->state = new XMLNode (**citer);
                                
                                if (active) {
                                        if (_session) {
                                                instantiate (*cpi);
                                        } else {
                                                cpi->requested = true;
                                        }
                                } else {
                                        if (_session) {
                                                teardown (*cpi);
                                        } else {
                                                cpi->requested = false;
                                        }
                                }
                        }
                }
        }

        return 0;
}

XMLNode&
ControlProtocolManager::get_state ()
{
        XMLNode* root = new XMLNode (state_node_name);
        Glib::Threads::Mutex::Lock lm (protocols_lock);

        for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {

                if ((*i)->protocol) {
                        XMLNode& child_state ((*i)->protocol->get_state());
                        child_state.add_property (X_("active"), "yes");
                        root->add_child_nocopy (child_state);
                } else if ((*i)->state) {
                        XMLNode* child_state = new XMLNode (*(*i)->state);
                        child_state->add_property (X_("active"), "no");
                        root->add_child_nocopy (*child_state);
                } else {
                        XMLNode* child_state = new XMLNode (X_("Protocol"));
                        child_state->add_property (X_("name"), (*i)->name);
                        child_state->add_property (X_("active"), "no");
                        root->add_child_nocopy (*child_state);
                }

        }

        return *root;
}


ControlProtocolManager&
ControlProtocolManager::instance ()
{
        if (_instance == 0) {
                _instance = new ControlProtocolManager ();
        }

        return *_instance;
}

void
ControlProtocolManager::midi_connectivity_established ()
{
        Glib::Threads::Mutex::Lock lm (protocols_lock);

        for (list<ControlProtocol*>::iterator p = control_protocols.begin(); p != control_protocols.end(); ++p) {
                (*p)->midi_connectivity_established ();
        }
}