luahl: global the luahl

8 files changed, 103 insertions, 85 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index e58035b6c7..21f7c8e931 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -244,78 +244,6 @@ Boolean nvim_buf_detach(uint64_t channel_id,
   return true;
 }
 
-static void buf_clear_luahl(buf_T *buf, bool force)
-{
-  if (buf->b_luahl || force) {
-    api_free_luaref(buf->b_luahl_start);
-    api_free_luaref(buf->b_luahl_window);
-    api_free_luaref(buf->b_luahl_line);
-    api_free_luaref(buf->b_luahl_end);
-  }
-  buf->b_luahl_start = LUA_NOREF;
-  buf->b_luahl_window = LUA_NOREF;
-  buf->b_luahl_line = LUA_NOREF;
-  buf->b_luahl_end = LUA_NOREF;
-}
-
-/// Unstabilized interface for defining syntax hl in lua.
-///
-/// This is not yet safe for general use, lua callbacks will need to
-/// be restricted, like textlock and probably other stuff.
-///
-/// The API on_line/nvim__put_attr is quite raw and not intended to be the
-/// final shape. Ideally this should operate on chunks larger than a single
-/// line to reduce interpreter overhead, and generate annotation objects
-/// (bufhl/virttext) on the fly but using the same representation.
-void nvim__buf_set_luahl(uint64_t channel_id, Buffer buffer,
-                         DictionaryOf(LuaRef) opts, Error *err)
-  FUNC_API_LUA_ONLY
-{
-  buf_T *buf = find_buffer_by_handle(buffer, err);
-
-  if (!buf) {
-    return;
-  }
-
-  redraw_buf_later(buf, NOT_VALID);
-  buf_clear_luahl(buf, false);
-
-  for (size_t i = 0; i < opts.size; i++) {
-    String k = opts.items[i].key;
-    Object *v = &opts.items[i].value;
-    if (strequal("on_start", k.data)) {
-      if (v->type != kObjectTypeLuaRef) {
-        api_set_error(err, kErrorTypeValidation, "callback is not a function");
-        goto error;
-      }
-      buf->b_luahl_start = v->data.luaref;
-      v->data.luaref = LUA_NOREF;
-    } else if (strequal("on_window", k.data)) {
-      if (v->type != kObjectTypeLuaRef) {
-        api_set_error(err, kErrorTypeValidation, "callback is not a function");
-        goto error;
-      }
-      buf->b_luahl_window = v->data.luaref;
-      v->data.luaref = LUA_NOREF;
-    } else if (strequal("on_line", k.data)) {
-      if (v->type != kObjectTypeLuaRef) {
-        api_set_error(err, kErrorTypeValidation, "callback is not a function");
-        goto error;
-      }
-      buf->b_luahl_line = v->data.luaref;
-      v->data.luaref = LUA_NOREF;
-    } else {
-      api_set_error(err, kErrorTypeValidation, "unexpected key: %s", k.data);
-      goto error;
-    }
-  }
-  buf->b_luahl = true;
-  return;
-error:
-  buf_clear_luahl(buf, true);
-  buf->b_luahl = false;
-}
-
 void nvim__buf_redraw_range(Buffer buffer, Integer first, Integer last,
                             Error *err)
   FUNC_API_LUA_ONLY
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index f1ecd732ee..e0d5862e02 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -1618,3 +1618,15 @@ free_exit:
   clear_virttext(&virt_text);
   return virt_text;
 }
+
+bool api_is_truthy(Object obj, const char *what, Error *err)
+{
+  if (obj.type == kObjectTypeBoolean) {
+    return obj.data.boolean;
+  } else if (obj.type == kObjectTypeInteger) {
+    return obj.data.integer;  // C semantics: non-zery int is true
+  } else {
+    api_set_error(err, kErrorTypeValidation, "%s is not an boolean", what);
+    return false;
+  }
+}
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index cb5d1e1f77..1de1472fc2 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -2702,3 +2702,68 @@ void nvim__screenshot(String path)
 {
   ui_call_screenshot(path);
 }
+
+static void clear_luahl(bool force)
+{
+  if (luahl_active || force) {
+    api_free_luaref(luahl_start);
+    api_free_luaref(luahl_win);
+    api_free_luaref(luahl_line);
+    api_free_luaref(luahl_end);
+  }
+  luahl_start = LUA_NOREF;
+  luahl_win = LUA_NOREF;
+  luahl_line = LUA_NOREF;
+  luahl_end = LUA_NOREF;
+  luahl_active = false;
+}
+
+/// Unstabilized interface for defining syntax hl in lua.
+///
+/// This is not yet safe for general use, lua callbacks will need to
+/// be restricted, like textlock and probably other stuff.
+///
+/// The API on_line/nvim__put_attr is quite raw and not intended to be the
+/// final shape. Ideally this should operate on chunks larger than a single
+/// line to reduce interpreter overhead, and generate annotation objects
+/// (bufhl/virttext) on the fly but using the same representation.
+void nvim__set_luahl(DictionaryOf(LuaRef) opts, Error *err)
+  FUNC_API_LUA_ONLY
+{
+  redraw_later(NOT_VALID);
+  clear_luahl(false);
+
+  for (size_t i = 0; i < opts.size; i++) {
+    String k = opts.items[i].key;
+    Object *v = &opts.items[i].value;
+    if (strequal("on_start", k.data)) {
+      if (v->type != kObjectTypeLuaRef) {
+        api_set_error(err, kErrorTypeValidation, "callback is not a function");
+        goto error;
+      }
+      luahl_start = v->data.luaref;
+      v->data.luaref = LUA_NOREF;
+    } else if (strequal("on_win", k.data)) {
+      if (v->type != kObjectTypeLuaRef) {
+        api_set_error(err, kErrorTypeValidation, "callback is not a function");
+        goto error;
+      }
+      luahl_win = v->data.luaref;
+      v->data.luaref = LUA_NOREF;
+    } else if (strequal("on_line", k.data)) {
+      if (v->type != kObjectTypeLuaRef) {
+        api_set_error(err, kErrorTypeValidation, "callback is not a function");
+        goto error;
+      }
+      luahl_line = v->data.luaref;
+      v->data.luaref = LUA_NOREF;
+    } else {
+      api_set_error(err, kErrorTypeValidation, "unexpected key: %s", k.data);
+      goto error;
+    }
+  }
+  luahl_active = true;
+  return;
+error:
+  clear_luahl(true);
+}
diff --git a/src/nvim/buffer_defs.h b/src/nvim/buffer_defs.h
index b3c95f9362..bd9cd2f5ec 100644
--- a/src/nvim/buffer_defs.h
+++ b/src/nvim/buffer_defs.h
@@ -842,12 +842,6 @@ struct file_buffer {
   // The number for times the current line has been flushed in the memline.
   int flush_count;
 
-  bool b_luahl;
-  LuaRef b_luahl_start;
-  LuaRef b_luahl_window;
-  LuaRef b_luahl_line;
-  LuaRef b_luahl_end;
-
   int b_diff_failed;    // internal diff failed for this buffer
 };
 
diff --git a/src/nvim/extmark.c b/src/nvim/extmark.c
index 3a04908ccb..c45714de78 100644
--- a/src/nvim/extmark.c
+++ b/src/nvim/extmark.c
@@ -845,7 +845,7 @@ bool decorations_redraw_reset(buf_T *buf, DecorationRedrawState *state)
 {
   state->row = -1;
   kv_size(state->active) = 0;
-  return buf->b_extmark_index || buf->b_luahl;
+  return buf->b_extmark_index;
 }
 
 
diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index 205be4b811..ddb69fc567 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -405,6 +405,12 @@ EXTERN int sys_menu INIT(= false);
 // ('lines' and 'rows') must not be changed.
 EXTERN int updating_screen INIT(= 0);
 
+EXTERN bool luahl_active INIT(= false);
+EXTERN LuaRef luahl_start INIT(= LUA_NOREF);
+EXTERN LuaRef luahl_win INIT(= LUA_NOREF);
+EXTERN LuaRef luahl_line INIT(= LUA_NOREF);
+EXTERN LuaRef luahl_end INIT(= LUA_NOREF);
+
 // All windows are linked in a list. firstwin points to the first entry,
 // lastwin to the last entry (can be the same as firstwin) and curwin to the
 // currently active window.
diff --git a/src/nvim/main.c b/src/nvim/main.c
index 1374c5eb5d..a22df9cc69 100644
--- a/src/nvim/main.c
+++ b/src/nvim/main.c
@@ -7,6 +7,8 @@
 #include <string.h>
 #include <stdbool.h>
 
+#include <lua.h>
+#include <lauxlib.h>
 #include <msgpack.h>
 
 #include "nvim/ascii.h"
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index ca1c4589f8..7d020432d9 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -158,6 +158,8 @@ static bool msg_grid_invalid = false;
 
 static bool resizing = false;
 
+static bool do_luahl_line = false;
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "screen.c.generated.h"
 #endif
@@ -508,12 +510,12 @@ int update_screen(int type)
       }
 
       buf_T *buf = wp->w_buffer;
-      if (buf->b_luahl && buf->b_luahl_window != LUA_NOREF) {
+      if (luahl_active && luahl_start != LUA_NOREF) {
         Error err = ERROR_INIT;
         FIXED_TEMP_ARRAY(args, 2);
         args.items[0] = BUFFER_OBJ(buf->handle);
         args.items[1] = INTEGER_OBJ(display_tick);
-        nlua_call_ref(buf->b_luahl_start, "start", args, false, &err);
+        nlua_call_ref(luahl_start, "start", args, false, &err);
         if (ERROR_SET(&err)) {
           ELOG("error in luahl start: %s", err.msg);
           api_clear_error(&err);
@@ -1239,7 +1241,9 @@ static void win_update(win_T *wp)
 
   decorations_active = decorations_redraw_reset(buf, &decorations);
 
-  if (buf->b_luahl && buf->b_luahl_window != LUA_NOREF) {
+  do_luahl_line = false;
+
+  if (luahl_win != LUA_NOREF) {
     Error err = ERROR_INIT;
     FIXED_TEMP_ARRAY(args, 4);
     linenr_T knownmax = ((wp->w_valid & VALID_BOTLINE)
@@ -1252,7 +1256,13 @@ static void win_update(win_T *wp)
     args.items[3] = INTEGER_OBJ(knownmax);
     // TODO(bfredl): we could allow this callback to change mod_top, mod_bot.
     // For now the "start" callback is expected to use nvim__buf_redraw_range.
-    nlua_call_ref(buf->b_luahl_window, "window", args, false, &err);
+    Object ret = nlua_call_ref(luahl_win, "win", args, true, &err);
+
+    if (!ERROR_SET(&err) && api_is_truthy(ret, "luahl_window retval", &err)) {
+      do_luahl_line = true;
+      decorations_active = true;
+    }
+
     if (ERROR_SET(&err)) {
       ELOG("error in luahl window: %s", err.msg);
       api_clear_error(&err);
@@ -2349,7 +2359,7 @@ win_line (
     }
 
     if (decorations_active) {
-      if (buf->b_luahl && buf->b_luahl_line != LUA_NOREF) {
+      if (do_luahl_line && luahl_line != LUA_NOREF) {
         Error err = ERROR_INIT;
         FIXED_TEMP_ARRAY(args, 3);
         args.items[0] = WINDOW_OBJ(wp->handle);
@@ -2357,8 +2367,9 @@ win_line (
         args.items[2] = INTEGER_OBJ(lnum-1);
         lua_attr_active = true;
         extra_check = true;
-        nlua_call_ref(buf->b_luahl_line, "line", args, false, &err);
+        nlua_call_ref(luahl_line, "line", args, false, &err);
         lua_attr_active = false;
+
         if (ERROR_SET(&err)) {
           ELOG("error in luahl line: %s", err.msg);
           luatext = err.msg;