SenseApis: Define descriptors exported by libs

hcore/include/senseApis/senseApiLib.h

@@ -0,0 +1,73 @@
+#ifndef SENSE_API_PROVIDER_DESC_H
+#define SENSE_API_PROVIDER_DESC_H
+
+#include <string>
+#include <memory>
+#include <vector>
+#include <dlfcn.h>
+#include <functional>
+#include <user/senseApiDesc.h>
+
+namespace hk {
+namespace sense_api {
+
+/* C++ version of the C struct above, which Harikoff uses to manage the 
+ * lib and connect implexors to it.
+ */
+class SenseApiDesc
+{
+public:
+    class ExportedImplexorApiDesc
+    {
+    public:
+        const std::string name;
+    };
+
+public:
+    SenseApiDesc(const CSenseApiDesc& cDesc)
+    :   cDescriptor(cDesc), name(cDesc.name)
+    {}
+
+    std::reference_wrapper<const CSenseApiDesc> cDescriptor;
+    std::string name;
+    // These options affect the sense api lib's behaviour globally.
+    std::vector<std::string> options;
+    // These are the implexors whose APIs this lib exports.
+    std::vector<ExportedImplexorApiDesc> exportedImplexorApis;
+};
+
+class SenseApiLib
+{
+public:
+    typedef const CSenseApiDesc *(SenseApiDescGetterFn)(void);
+
+public:
+    SenseApiLib(const std::string& path)
+    :   libraryPath(path), handle(nullptr, &dlclose)
+    {}
+
+public:
+    std::string libraryPath;
+    std::unique_ptr<void, decltype(&dlclose)> handle;
+
+    /**
+     * @brief Every sense API lib is required to provide a function that returns
+     * a CSenseApiDesc struct. This struct states which API the lib uses to
+     * connect Harikoff to the sense provider it supports.
+     *
+     * This getter function should be visible to dlsym() so that Harikoff can
+     * find it in the lib after loading it, and call it.
+     */
+    SenseApiDescGetterFn *getSenseApiDescriptor;
+
+    /**
+     * @brief Harikoff will call the `getSenseApiDescriptor` getter function and
+     * use the data it provides in order to fill out this descriptor.
+     */
+    std::unique_ptr<SenseApiDesc> apiDescriptor;
+};
+
+} // namespace sense_api
+} // namespace hk
+
+#endif // SENSE_API_PROVIDER_DESC_H