Add /etc/xkb as extra lookup path for system data files

This completes the usual triplet of configuration locations available for most
processes:
- vendor-provided data files in /usr/share/X11/xkb
- system-specific data files in /etc/xkb
- user-specific data files in $XDG_CONFIG_HOME/xkb

The default lookup order user, system, vendor, just like everything else that
uses these conventions.

For include directives in rules files, the '%E' resolves to that path.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

4 files changed, 27 insertions, 2 deletions

diff --git a/src/context.c b/src/context.c
index ef9b774..2abaa9b 100644
--- a/src/context.c
+++ b/src/context.c
@@ -84,6 +84,13 @@ err:
 }
 
 const char *
+xkb_context_include_path_get_extra_path(struct xkb_context *ctx)
+{
+    const char *extra = secure_getenv("XKB_CONFIG_EXTRA_PATH");
+    return extra ? extra : DFLT_XKB_CONFIG_EXTRA_PATH;
+}
+
+const char *
 xkb_context_include_path_get_system_path(struct xkb_context *ctx)
 {
     const char *root = secure_getenv("XKB_CONFIG_ROOT");
@@ -96,7 +103,7 @@ xkb_context_include_path_get_system_path(struct xkb_context *ctx)
 XKB_EXPORT int
 xkb_context_include_path_append_default(struct xkb_context *ctx)
 {
-    const char *home, *xdg, *root;
+    const char *home, *xdg, *root, *extra;
     char *user_path;
     int ret = 0;
 
@@ -126,6 +133,8 @@ xkb_context_include_path_append_default(struct xkb_context *ctx)
         }
     }
 
+    extra = xkb_context_include_path_get_extra_path(ctx);
+    ret |= xkb_context_include_path_append(ctx, extra);
     root = xkb_context_include_path_get_system_path(ctx);
     ret |= xkb_context_include_path_append(ctx, root);
 
diff --git a/src/context.h b/src/context.h
index 9584dbc..ead2508 100644
--- a/src/context.h
+++ b/src/context.h
@@ -60,6 +60,9 @@ xkb_context_failed_include_path_get(struct xkb_context *ctx,
                                     unsigned int idx);
 
 const char *
+xkb_context_include_path_get_extra_path(struct xkb_context *ctx);
+
+const char *
 xkb_context_include_path_get_system_path(struct xkb_context *ctx);
 
 /*
diff --git a/src/registry.c b/src/registry.c
index 956d850..d3d95f5 100644
--- a/src/registry.c
+++ b/src/registry.c
@@ -583,7 +583,7 @@ err:
 XKB_EXPORT bool
 rxkb_context_include_path_append_default(struct rxkb_context *ctx)
 {
-    const char *home, *xdg, *root;
+    const char *home, *xdg, *root, *extra;
     char *user_path;
     bool ret = false;
 
@@ -618,6 +618,12 @@ rxkb_context_include_path_append_default(struct rxkb_context *ctx)
         }
     }
 
+    extra = secure_getenv("XKB_CONFIG_EXTRA_PATH");
+    if (extra != NULL)
+        ret |= rxkb_context_include_path_append(ctx, extra);
+    else
+        ret |= rxkb_context_include_path_append(ctx, DFLT_XKB_CONFIG_EXTRA_PATH);
+
     root = secure_getenv("XKB_CONFIG_ROOT");
     if (root != NULL)
         ret |= rxkb_context_include_path_append(ctx, root);
diff --git a/src/xkbcomp/rules.c b/src/xkbcomp/rules.c
index 3359552..099500a 100644
--- a/src/xkbcomp/rules.c
+++ b/src/xkbcomp/rules.c
@@ -399,6 +399,13 @@ matcher_include(struct matcher *m, struct scanner *parent_scanner,
                     return;
                 }
             }
+            else if (chr(&s, 'E')) {
+                const char *default_root = xkb_context_include_path_get_extra_path(m->ctx);
+                if (!buf_appends(&s, default_root) || !buf_appends(&s, "/rules")) {
+                    scanner_err(&s, "include path after expanding %%E is too long");
+                    return;
+                }
+            }
             else {
                 scanner_err(&s, "unknown %% format (%c) in include statement", peek(&s));
                 return;