Support XDG_CONFIG_HOME

The loading of the config file has been changed to support the XDG
Base Directory specification. More info here:

  https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html

If in a UNIX environment, LuaRocks will try loading a config file in
XDG_CONFIG_HOME. If this fails, try loading one in the old location
~/.luarocks.

This method clashed a bit with the old code that separated the setting
of confdirs and the loading of the config files. As we now change
cfg.homeconfdir depending on where we find the config file I found it
necessary to remove the function set_confdirs() and move some pieces
into the config loading logic.

1 files changed, 27 insertions, 21 deletions

diff --git a/src/luarocks/core/cfg.lua b/src/luarocks/core/cfg.lua
index 7ea86542..e24fa4f6 100644
--- a/src/luarocks/core/cfg.lua
+++ b/src/luarocks/core/cfg.lua
@@ -70,21 +70,6 @@ local function detect_sysconfdir()
    return basedir
 end
 
-local function set_confdirs(cfg, platforms, hardcoded_sysconfdir)
-   local sysconfdir = os.getenv("LUAROCKS_SYSCONFDIR") or hardcoded_sysconfdir
-   if platforms.windows and not platforms.msys2_mingw_w64 then
-      cfg.home = os.getenv("APPDATA") or "c:"
-      cfg.home_tree = cfg.home.."/luarocks"
-      cfg.homeconfdir = cfg.home_tree
-      cfg.sysconfdir = sysconfdir or ((os.getenv("PROGRAMFILES") or "c:") .. "/luarocks")
-   else
-      cfg.home = os.getenv("HOME") or ""
-      cfg.home_tree = cfg.home.."/.luarocks"
-      cfg.homeconfdir = cfg.home_tree
-      cfg.sysconfdir = sysconfdir or detect_sysconfdir() or "/etc/luarocks"
-   end
-end
-
 local load_config_file
 do
    -- Create global environment for the config files;
@@ -653,17 +638,24 @@ function cfg.init(detected, warning)
    local sys_config_file
    local home_config_file
    local project_config_file
+
+   local config_file_name = "config-"..cfg.lua_version..".lua"
+
    do
-      set_confdirs(cfg, platforms, hardcoded.SYSCONFDIR)
-      local name = "config-"..cfg.lua_version..".lua"
-      sys_config_file = (cfg.sysconfdir .. "/" .. name):gsub("\\", "/")
-      home_config_file = (cfg.homeconfdir .. "/" .. name):gsub("\\", "/")
-      if cfg.project_dir then
-         project_config_file = cfg.project_dir .. "/.luarocks/" .. name
+      local sysconfdir = os.getenv("LUAROCKS_SYSCONFDIR") or hardcoded.SYSCONFDIR
+      if platforms.windows and not platforms.msys2_mingw_w64 then
+         cfg.home = os.getenv("APPDATA") or "c:"
+         cfg.home_tree = cfg.home.."/luarocks"
+         cfg.sysconfdir = sysconfdir or ((os.getenv("PROGRAMFILES") or "c:") .. "/luarocks")
+      else
+         cfg.home = os.getenv("HOME") or ""
+         cfg.home_tree = cfg.home.."/.luarocks"
+         cfg.sysconfdir = sysconfdir or detect_sysconfdir() or "/etc/luarocks"
       end
    end
 
    -- Load system configuration file
+   sys_config_file = (cfg.sysconfdir .. "/" .. config_file_name):gsub("\\", "/")
    local sys_config_ok, err = load_config_file(cfg, platforms, sys_config_file)
    if err then
       return nil, err, "config"
@@ -693,8 +685,21 @@ function cfg.init(detected, warning)
          end
       end
 
+      -- try XDG config home
+      if platforms.unix and not home_config_ok then
+         local xdg_config_home = os.getenv("XDG_CONFIG_HOME") or cfg.home .. "/.config"
+         cfg.homeconfdir = xdg_config_home .. "/luarocks"
+         home_config_file = (cfg.homeconfdir .. "/" .. config_file_name):gsub("\\", "/")
+         home_config_ok, err = load_config_file(cfg, platforms, home_config_file)
+         if err then
+            return nil, err, "config"
+         end
+      end
+
       -- try the alternative defaults if there was no environment specified file or it didn't work
       if not home_config_ok then
+         cfg.homeconfdir = cfg.home_tree
+         home_config_file = (cfg.homeconfdir .. "/" .. config_file_name):gsub("\\", "/")
          home_config_ok, err = load_config_file(cfg, platforms, home_config_file)
          if err then
             return nil, err, "config"
@@ -703,6 +708,7 @@ function cfg.init(detected, warning)
 
       -- finally, use the project-specific config file if any
       if cfg.project_dir then
+         project_config_file = cfg.project_dir .. "/.luarocks/" .. config_file_name
          project_config_ok, err = load_config_file(cfg, platforms, project_config_file)
          if err then
             return nil, err, "config"