logos-module-loader-qt

Implementation of logos-module-loader contract, using Qt Plugins for loading modules.

logos-module-loader   (ModuleFormatLoader interface)
   └─ logos-module-loader-qt  <-- this repo
         consumed by logos-liblogos

What's here

The whole Qt-plugin mechanism, in two parts:

Artifact	Side	Sources	Links
logos_module_loader_qt (static lib)	parent	qt_plugin_format_loader.{h,cpp}, qt_plugin_format_loader_factory.cpp	boost::dll, spdlog, the loader contract. Qt-free / SDK-free. Linked into logos_core.
logos_host_qt (binary)	child	host/ (logos_host, command_line_parser, module_initializer, qt_app, token_source)	the full SDK stack + Qt + CLI11 + logos-module. Bundled by frontends.

The parent (QtPluginFormatLoader) only resolves the logos_host_qt binary path and builds its CLI arguments (--name, --path, --instance-persistence-path, --transport-set) — it is deliberately light so logos_core doesn't pull Qt or the SDK just to know how to launch a Qt-plugin module. The factory TU defines LogosCore::makeFormatLoader() (the logos-module-loader factory seam) → a QtPluginFormatLoader, so logos_core selects this loader at link time without naming it.

The child (logos_host_qt) loads a single Qt-plugin module in its own process: it reads its auth token from the channel its container designated via --token-source (default stdin — so the host depends on no container package), then loads the plugin and brings up LogosAPI.

A logos_host → logos_host_qt compatibility symlink is installed so frontends keep working with either name.

Consuming it

This package installs a generic CMake config so a consumer selects "the format-loader implementation" without naming this one:

find_package(LogosFormatLoaderImpl REQUIRED)   # provided by this package
target_link_libraries(your_target PRIVATE LogosFormatLoaderImpl::impl)

LogosFormatLoaderImpl::impl carries the logos_module_loader_qt static library plus its own deps (Boost.Filesystem, spdlog, nlohmann_json). A different format-loader implementation that ships the same LogosFormatLoaderImpl config is a drop-in replacement. (The logos_host_qt binary is consumed separately — frontends bundle it; liblogos re-exports it.)

Build & test

nix build .#logos-module-loader-qt              # lib + header + host binary
nix build .#checks.aarch64-linux.tests -L       # run the loader + token-source tests