Add XDG_BASE_DIR support

runtime/doc/freedesktop.txt

@@ -0,0 +1,46 @@
+*freedesktop.txt* For Vim version 9.1. Last change: 2024 Mar 20
+
+
+		  VIM REFERENCE MANUAL    by Bram Moolenaar
+
+
+				      *freedesktop* *X-desktop-group* *xdg*
+This file contains some information on what it is freedesktop and the XDG
+families of specifications.
+
+Freedesktop is a project aiming to develop specifications to enable
+interoperability between Unix-like operating systems.
+
+Vim tries to conform, for some extent, to the specifications made by
+freedesktop (see |xdg-base-dir|).
+
+==============================================================================
+XDG Base Directory Specification	*xdg-base-dir* *$XDG_CONFIG_HOME*
+
+The XDG Base Directory Specification aim to define standard locations for the
+multilple data e configuration files used by applications. In order to divide
+this files by their use and not by application. This is mainly done to go
+against the legacy behavior of dumping everything in the home directory.
+
+This directories should be overwritable by the user, using environment
+variable but should also give fallback in case those variables weren't set. 
+
+This is a not exhaustive of those directories:
+  XDG_CACHE_HOME    HOME/.cache		Ephemiral data files
+  XDG_CONFIG_HOME   HOME/.config	Configuration files
+  XDG_DATA_HOME	    HOME/.local/share	Persistent data files
+  XDG_STATE_HOME    HOME/.local/state	State data files
+
+							*xdg-vimrc*
+Vim, on Unix systems, will look at `$XDG_CONFIG_HOME/vim/vimrc` for
+configuration (see |vimrc|) but it will source it only if no other rc is found
+in  `$HOME` or `$HOME/vim`.
+
+							*xdg-runtime*
+When the |xdg-vimrc| is used the |'runtimepath'| will be modified accordingly
+to respect the |xdg-base-dir|: >
+
+    "$XDG_CONFIG_HOME/vim,$VIMRUNTIME,/after,$XDG_CONFIG_HOME/vim/after"
+<
+
+ vim:tw=78:ts=8:noet:ft=help:norl:

runtime/doc/starting.txt

@@ -809,7 +809,8 @@ accordingly.  Vim proceeds in this order:
 	name.  Also see |vimrc-intro|.
 
 	Places for your personal initializations:
-		Unix		$HOME/.vimrc or $HOME/.vim/vimrc
+		Unix		$HOME/.vimrc, $HOME/.vim/vimrc
+                                or $XDG_CONFIG_HOME/vim/vimrc
 		MS-Windows	$HOME/_vimrc, $HOME/vimfiles/vimrc
 				or $VIM/_vimrc
 		Amiga		s:.vimrc, home:.vimrc, home:vimfiles:vimrc

src/main.c

@@ -3276,6 +3276,10 @@ source_startup_scripts(mparm_T *parmp)
 		&& do_source((char_u *)USR_VIMRC_FILE2, TRUE,
 						      DOSO_VIMRC, NULL) == FAIL
 #endif
+#ifdef XDG_VIMRC_FILE
+		&& do_source((char_u *)XDG_VIMRC_FILE, TRUE,
+						      DOSO_VIMRC, NULL) == FAIL
+#endif
 #ifdef USR_VIMRC_FILE3
 		&& do_source((char_u *)USR_VIMRC_FILE3, TRUE,
 						      DOSO_VIMRC, NULL) == FAIL

src/option.c

@@ -364,6 +364,66 @@ set_init_clean_rtp(void)
 }
 #endif
 
+#ifdef UNIX
+/*
+ * Change 'runtimepath' and 'packdir' to '$XDG_CONFIG_HOME/vim' if the only
+ * vimrc found is located in '$XDG_CONFIG_HOME/vim/vimrc'.  
+ * In case the '$XDG_CONFIG_HOME' variable is not set, '$HOME/.config' is used 
+ * as a fallback as is defined in the XDG base dir specification:
+ * <https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html>
+ */
+    static void
+set_init_xdg_rtp(void)
+{
+    int		opt_idx;
+    int		has_xdg_env = TRUE;
+    int		should_free_xdg_dir = FALSE;
+    char_u	*vimrc1 = NULL;
+    char_u 	*vimrc2 = NULL;
+    char_u 	*xdg_dir = NULL;
+    char_u 	*xdg_rtp = NULL;
+    char_u 	*vimrc_xdg = NULL;
+
+    vimrc1 = expand_env_save((char_u *)USR_VIMRC_FILE);
+    vimrc2 = expand_env_save((char_u *)USR_VIMRC_FILE2);
+
+    xdg_dir = mch_getenv("XDG_CONFIG_HOME");
+    if (!xdg_dir)
+    {
+	xdg_dir = expand_env_save((char_u *)"~/.config");
+	should_free_xdg_dir = TRUE;
+	has_xdg_env = FALSE;
+    }
+    vimrc_xdg = concat_fnames(xdg_dir, (char_u *)"vim/vimrc", TRUE);
+
+    if (file_is_readable(vimrc1) || file_is_readable(vimrc2) ||
+	    !file_is_readable(vimrc_xdg))
+	goto theend;
+
+    xdg_rtp = has_xdg_env ? (char_u *)XDG_RUNTIMEPATH 
+	: (char_u *)XDG_RUNTIMEPATH_FB;
+
+    if ((opt_idx = findoption((char_u *)"runtimepath")) < 0)
+	goto theend;
+
+    options[opt_idx].def_val[VI_DEFAULT] = xdg_rtp;
+    p_rtp = xdg_rtp;
+
+    if ((opt_idx = findoption((char_u *)"packpath")) < 0)
+	goto theend;
+
+    options[opt_idx].def_val[VI_DEFAULT] = xdg_rtp;
+    p_pp = xdg_rtp;
+
+theend:
+    vim_free(vimrc1);
+    vim_free(vimrc2);
+    vim_free(vimrc_xdg);
+    if (should_free_xdg_dir)
+	vim_free(xdg_dir);
+}
+#endif
+
 /*
  * Expand environment variables and things like "~" for the defaults.
  * If option_expand() returns non-NULL the variable is expanded.  This can
@@ -588,6 +648,7 @@ set_init_1(int clean_arg)
     set_options_default(0);
 
 #ifdef UNIX
+    set_init_xdg_rtp();
     set_init_restricted_mode();
 #endif
 

src/os_unix.h

@@ -236,7 +236,7 @@ typedef struct dsc$descriptor   DESC;
 # ifdef VMS
 # define USR_VIMRC_FILE  "sys$login:.vimrc"
 # else
-#  define USR_VIMRC_FILE "$HOME/.vimrc"
+#  define USR_VIMRC_FILE "~/.vimrc"
 # endif
 #endif
 
@@ -249,6 +249,12 @@ typedef struct dsc$descriptor   DESC;
 # endif
 #endif
 
+#ifndef XDG_VIMRC_FILE
+# define XDG_VIMRC_FILE mch_getenv("XDG_CONFIG_HOME") \
+	? (char_u *)"$XDG_CONFIG_HOME/vim/vimrc" \
+	: (char_u *)"~/.config/vim/vimrc"
+#endif
+
 #if !defined(USR_VIMRC_FILE3) && defined(VMS)
 # define USR_VIMRC_FILE3 "sys$login:_vimrc"
 #endif
@@ -349,13 +355,19 @@ typedef struct dsc$descriptor   DESC;
 #  ifdef RUNTIME_GLOBAL
 #   ifdef RUNTIME_GLOBAL_AFTER
 #    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER ",~/.vim/after"
+#    define XDG_RUNTIMEPATH	"$XDG_CONFIG_HOME/vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER "/after,$XDG_CONFIG_HOME/vim/after"
+#    define XDG_RUNTIMEPATH_FB	"~/.config/vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER "/after,~/.config/vim/after"
 #    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER
 #   else
 #    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,~/.vim/after"
+#    define XDG_RUNTIMEPATH	"$XDG_CONFIG_HOME/vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,$XDG_CONFIG_HOME/vim/after"
+#    define XDG_RUNTIMEPATH_FB	"~/.config/vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,~/.config/vim/after"
 #    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after"
 #   endif
 #  else
 #   define DFLT_RUNTIMEPATH	"~/.vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,~/.vim/after"
+#   define XDG_RUNTIMEPATH	"$XDG_CONFIG_HOME/vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,$XDG_CONFIG_HOME/vim/after"
+#   define XDG_RUNTIMEPATH_FB	"~/.config/vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,~/.config/vim/after"
 #   define CLEAN_RUNTIMEPATH	"$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
 #  endif
 # endif

src/testdir/Make_all.mak

@@ -329,6 +329,7 @@ NEW_TESTS = \
 	test_wnext \
 	test_wordcount \
 	test_writefile \
+	test_xdg \
 	test_xxd \
 	test_alot_latin \
 	test_alot_utf8 \
@@ -561,6 +562,7 @@ NEW_TESTS_RES = \
 	test_winfixbuf.res \
 	test_wordcount.res \
 	test_writefile.res \
+	test_xdg.res \
 	test_xxd.res \
 	test_alot_latin.res \
 	test_alot_utf8.res \

src/testdir/test_xdg.vim

@@ -0,0 +1,34 @@
+func s:get_rcs()
+  let rcs = {
+        \ 'file1': { 'path': '~/.vimrc' },
+        \ 'file2': { 'path': '~/.vim/vimrc' },
+        \ 'xdg': { 'path': exists('$XDG_CONFIG_HOME') ? '$XDG_CONFIG_HOME' : "~/.config" },
+        \}
+  for v in values(rcs)
+    let v.exists = filereadable(expand(v.path))
+  endfor
+  return rcs
+endfunc
+
+func Test_xdg_rc_detection()
+  if !has('unix')
+    return v:false
+  endif
+  let rc = s:get_rcs()
+  let before =<< trim CODE
+    call writefile([expand('$MYVIMRC')], "XMY_VIMRC")
+    quit!
+  CODE
+  call RunVim(before, [], "")
+  let my_rc = readfile("XMY_VIMRC")
+  if rc.file1.exists
+    call assert_equal(rc.file1.path, my_rc)
+  elseif !rc.file1.exists && rc.file2.exists
+    call assert_equal(rc.file2.path, my_rc)
+  elseif !rc.file1.exists && !rc.file2.exists && rc.xdg.exists
+    call assert_equal(rc.xdg.path, my_rc)
+  endif
+  call delete("XMY_VIMRC")
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab