view checker/knownplugins.h @ 34:6905d8b146f6 plugin-path-config

Toward supporting separate environment variables for 32-bit plugins on a 64-bit system (otherwise we try to load both from the same helpers)

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
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    Copyright (c) 2016 Queen Mary, University of London

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#ifndef KNOWN_PLUGINS_H
#define KNOWN_PLUGINS_H

#include "plugincandidates.h"

#include <string>
#include <map>
#include <vector>

/**
 * Class to identify and list candidate shared-library files possibly
 * containing plugins in a hardcoded set of known formats. Uses a
 * separate process (the "helper", whose executable name must be
 * provided at construction) to test-load each library in order to
 * winnow out any that fail to load or crash on load.
 *
 * Requires C++11 and the Qt5 QtCore library.
 */
class KnownPlugins
{
    typedef std::vector<std::string> stringlist;
    
public:
    enum PluginType {
        VampPlugin,
        LADSPAPlugin,
        DSSIPlugin
    };

    KnownPlugins(std::string helperExecutableName,
                 PluginCandidates::LogCallback *cb = 0);

    std::vector<PluginType> getKnownPluginTypes() const;
    
    std::string getTagFor(PluginType type) const {
        return m_known.at(type).tag;
    }

    stringlist getCandidateLibrariesFor(PluginType type) const {
        return m_candidates.getCandidateLibrariesFor(getTagFor(type));
    }

    std::string getPathEnvironmentVariableFor(PluginType type) const {
        return m_known.at(type).variable;
    }
    
    stringlist getPathFor(PluginType type) const {
        return m_known.at(type).path;
    }

    std::string getHelperExecutableName() const {
        return m_helperExecutableName;
    }

    std::string getFailureReport() const;
    
private:
    struct TypeRec {
        std::string tag;
        std::string variable;
        stringlist path;
        std::string descriptor;
    };
    typedef std::map<PluginType, TypeRec> Known;
    Known m_known;

    stringlist expandConventionalPath(PluginType type, std::string var);
    std::string getDefaultPath(PluginType type);

    PluginCandidates m_candidates;
    std::string m_helperExecutableName;

    /** This returns true if the helper has a name ending in "-32". By
     *  our convention, this means that it is a 32-bit helper found on
     *  a 64-bit system, so (depending on the OS) we may need to look
     *  in 32-bit-specific paths. Note that is32bit() is *not* usually
     *  true on 32-bit systems; it's used specifically to indicate a
     *  "non-native" 32-bit helper.
     */
    bool is32bit() const;
};

#endif