Plugin System (#1590)

---------

Co-authored-by: Mihai Fufezan <fufexan@protonmail.com>

src/plugins/PluginSystem.cpp

@@ -0,0 +1,139 @@
+#include "PluginSystem.hpp"
+
+#include <dlfcn.h>
+#include "../Compositor.hpp"
+
+CPluginSystem::CPluginSystem() {
+    g_pFunctionHookSystem = std::make_unique<CHookSystem>();
+}
+
+CPlugin* CPluginSystem::loadPlugin(const std::string& path) {
+
+    if (getPluginByPath(path)) {
+        Debug::log(ERR, " [PluginSystem] Cannot load a plugin twice!");
+        return nullptr;
+    }
+
+    auto* const PLUGIN = m_vLoadedPlugins.emplace_back(std::make_unique<CPlugin>()).get();
+
+    PLUGIN->path = path;
+
+    HANDLE MODULE = dlopen(path.c_str(), RTLD_LAZY);
+
+    if (!MODULE) {
+        Debug::log(ERR, " [PluginSystem] Plugin %s could not be loaded: %s", path.c_str(), dlerror());
+        m_vLoadedPlugins.pop_back();
+        return nullptr;
+    }
+
+    PLUGIN->m_pHandle = MODULE;
+
+    PPLUGIN_API_VERSION_FUNC apiVerFunc = (PPLUGIN_API_VERSION_FUNC)dlsym(MODULE, PLUGIN_API_VERSION_FUNC_STR);
+    PPLUGIN_INIT_FUNC        initFunc   = (PPLUGIN_INIT_FUNC)dlsym(MODULE, PLUGIN_INIT_FUNC_STR);
+
+    if (!apiVerFunc || !initFunc) {
+        Debug::log(ERR, " [PluginSystem] Plugin %s could not be loaded. (No apiver/init func)", path.c_str());
+        dlclose(MODULE);
+        m_vLoadedPlugins.pop_back();
+        return nullptr;
+    }
+
+    const std::string PLUGINAPIVER = apiVerFunc();
+
+    if (PLUGINAPIVER != HYPRLAND_API_VERSION) {
+        Debug::log(ERR, " [PluginSystem] Plugin %s could not be loaded. (API version mismatch)", path.c_str());
+        dlclose(MODULE);
+        m_vLoadedPlugins.pop_back();
+        return nullptr;
+    }
+
+    PLUGIN_DESCRIPTION_INFO PLUGINDATA;
+
+    try {
+        if (!setjmp(m_jbPluginFaultJumpBuf)) {
+            m_bAllowConfigVars = true;
+            PLUGINDATA         = initFunc(MODULE);
+        } else {
+            // this module crashed.
+            throw std::exception();
+        }
+    } catch (std::exception& e) {
+        m_bAllowConfigVars = false;
+        Debug::log(ERR, " [PluginSystem] Plugin %s (Handle %lx) crashed in init. Unloading.", path.c_str(), MODULE);
+        unloadPlugin(PLUGIN, true); // Plugin could've already hooked/done something
+        return nullptr;
+    }
+
+    m_bAllowConfigVars = false;
+
+    PLUGIN->author      = PLUGINDATA.author;
+    PLUGIN->description = PLUGINDATA.description;
+    PLUGIN->version     = PLUGINDATA.version;
+    PLUGIN->name        = PLUGINDATA.name;
+
+    Debug::log(LOG, " [PluginSystem] Plugin %s loaded. Handle: %lx, path: \"%s\", author: \"%s\", description: \"%s\", version: \"%s\"", PLUGINDATA.name.c_str(), MODULE,
+               path.c_str(), PLUGINDATA.author.c_str(), PLUGINDATA.description.c_str(), PLUGINDATA.version.c_str());
+
+    return PLUGIN;
+}
+
+void CPluginSystem::unloadPlugin(const CPlugin* plugin, bool eject) {
+    if (!plugin)
+        return;
+
+    if (!eject) {
+        PPLUGIN_EXIT_FUNC exitFunc = (PPLUGIN_EXIT_FUNC)dlsym(plugin->m_pHandle, PLUGIN_EXIT_FUNC_STR);
+        if (exitFunc)
+            exitFunc();
+    }
+
+    for (auto& [k, v] : plugin->registeredCallbacks)
+        g_pHookSystem->unhook(v);
+
+    const auto ls = plugin->registeredLayouts;
+    for (auto& l : ls)
+        g_pLayoutManager->removeLayout(l);
+
+    g_pFunctionHookSystem->removeAllHooksFrom(plugin->m_pHandle);
+
+    const auto rd = plugin->registeredDecorations;
+    for (auto& d : rd)
+        HyprlandAPI::removeWindowDecoration(plugin->m_pHandle, d);
+
+    const auto rdi = plugin->registeredDispatchers;
+    for (auto& d : rdi)
+        HyprlandAPI::removeDispatcher(plugin->m_pHandle, d);
+
+    g_pConfigManager->removePluginConfig(plugin->m_pHandle);
+
+    dlclose(plugin->m_pHandle);
+
+    Debug::log(LOG, " [PluginSystem] Plugin %s unloaded.", plugin->name.c_str());
+
+    std::erase_if(m_vLoadedPlugins, [&](const auto& other) { return other->m_pHandle == plugin->m_pHandle; });
+}
+
+CPlugin* CPluginSystem::getPluginByPath(const std::string& path) {
+    for (auto& p : m_vLoadedPlugins) {
+        if (p->path == path)
+            return p.get();
+    }
+
+    return nullptr;
+}
+
+CPlugin* CPluginSystem::getPluginByHandle(HANDLE handle) {
+    for (auto& p : m_vLoadedPlugins) {
+        if (p->m_pHandle == handle)
+            return p.get();
+    }
+
+    return nullptr;
+}
+
+std::vector<CPlugin*> CPluginSystem::getAllPlugins() {
+    std::vector<CPlugin*> results(m_vLoadedPlugins.size());
+    for (size_t i = 0; i < m_vLoadedPlugins.size(); ++i)
+        results[i] = m_vLoadedPlugins[i].get();
+    return results;
+}