Append script parent dir to lua package.path

Signed-off-by: Tin Švagelj <tin.svagelj@live.com>

src/conky.cc

@@ -38,6 +38,7 @@
 #include <cmath>
 #include <cstdarg>
 #include <ctime>
+#include <filesystem>
 #include <iostream>
 #include <memory>
 #include <sstream>
@@ -275,7 +276,7 @@ int text_width = 1,
 struct information info;
 
 /* path to config file */
-std::string current_config;
+std::filesystem::path current_config;
 
 /* set to 1 if you want all text to be in uppercase */
 static conky::simple_config_setting<bool> stuff_in_uppercase("uppercase", false,
@@ -1961,6 +1962,40 @@ void load_config_file() {
   lua::stack_sentry s(l);
   l.checkstack(2);
 
+  // Extend lua package.path so scripts can use relative paths
+  {
+    struct stat file_stat {};
+
+    std::string path_ext;
+
+    // add XDG directory to lua path
+    auto xdg_path =
+        std::filesystem::path(to_real_path(XDG_CONFIG_FILE)).parent_path();
+    if (stat(xdg_path.c_str(), &file_stat) == 0) {
+      path_ext.push_back(';');
+      path_ext.append(xdg_path);
+      path_ext.append("/?.lua");
+    }
+
+    auto parent_path = current_config.parent_path();
+    if (xdg_path != parent_path && stat(path_ext.c_str(), &file_stat) == 0) {
+      path_ext.push_back(';');
+      path_ext.append(parent_path);
+      path_ext.append("/?.lua");
+    }
+
+    l.getglobal("package");
+    l.getfield(-1, "path");
+
+    auto path = l.tostring(-1);
+    path.append(path_ext);
+    l.pop();
+    l.pushstring(path.c_str());
+
+    l.setfield(-2, "path");
+    l.pop();
+  }
+
   try {
 #ifdef BUILD_BUILTIN_CONFIG
     if (current_config == builtin_config_magic) {

src/conky.h

@@ -38,6 +38,7 @@
 #include <config.h>      /* defines */
 #include <sys/utsname.h> /* struct uname_s */
 #include <csignal>
+#include <filesystem>
 #include <memory>
 
 #include "colours.h"
@@ -346,7 +347,7 @@ extern conky::simple_config_setting<bool> utf8_mode;
 extern conky::range_config_setting<unsigned int> max_user_text;
 
 /* path to config file */
-extern std::string current_config;
+extern std::filesystem::path current_config;
 
 #define DEFAULT_TEXT_BUFFER_SIZE_S "##DEFAULT_TEXT_BUFFER_SIZE"