libcruft-vk/load/vendor_win32.cpp

#include "vendor.hpp"

#include <cruft/json/tree.hpp>

#include <cruft/util/io.hpp>
#include <cruft/util/log.hpp>
#include <cruft/util/win32/registry.hpp>
#include <cruft/util/win32/except.hpp>


///////////////////////////////////////////////////////////////////////////////
std::vector<cruft::vk::load::icd_t>
cruft::vk::load::enumerate()
{
    std::vector<icd_t> res;

    win32::key root (HKEY_LOCAL_MACHINE, "System\\CurrentControlSet\\Control\\Class\\");

    for (auto &&adapter: root.subkeys ()) {
        for (auto &&device: adapter.subkeys ()) {
            // device keys must be of the form '000X'
            auto const name = device.name ();
            if (name.size () != 4 ||
                name[0] != '0' ||
                name[1] != '0' ||
                name[2] != '0' ||
                !std::isdigit(name[3]))
            {
                continue;
            }

            // 'VulkanDriverName' contains the JSON for the ICD data. Parse
            // this and add to the list. If we encounter an error then
            // quietly  drop it.
            try {
                auto const path = device.data<std::string> ("VulkanDriverName");
                auto const text = cruft::slurp<char> (path);
                auto const jobj = json::tree::parse (cruft::view{text});
                auto const data = from_json<icd_t> (*jobj);

                res.push_back (data);
            } catch (win32::error const&) {
                ;
            } catch (std::exception const &e) {
                LOG_WARNING ("error loading Vulkan ICD manifest, %!", e.what ());
            }
        }
    }

    return res;
}