From ccc370e1c474c6eecdaa8c485e117a054b23fe00 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 15 May 2021 10:41:54 +0530
Subject: [PATCH] Dont initialize FontConfig when importing fast_data_types

This reduces the import time for fast_data_types by 12ms on my machine.
FontConfig initialization is very slow and it is only needed by the
main kitty program, however fast_data_types is imported in kittens and
remote control as well, where FontConfig is useless.
---
 kitty/fontconfig.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/kitty/fontconfig.c b/kitty/fontconfig.c
index 3826f820c..3c0db030c 100644
--- a/kitty/fontconfig.c
+++ b/kitty/fontconfig.c
@@ -16,6 +16,25 @@
 #define FC_COLOR "color"
 #endif
 
+
+static bool initialized = false;
+
+static void
+ensure_initialized(void) {
+    if (!initialized) {
+        if (!FcInit()) fatal("Failed to initialize fontconfig library");
+        initialized = true;
+    }
+}
+
+static void
+finalize(void) {
+    if (initialized) {
+        FcFini();
+        initialized = false;
+    }
+}
+
 static inline PyObject*
 pybool(FcBool x) { PyObject *ans = x ? Py_True: Py_False; Py_INCREF(ans); return ans; }
 
@@ -109,6 +128,7 @@ font_set(FcFontSet *fs) {
 
 static PyObject*
 fc_list(PyObject UNUSED *self, PyObject *args) {
+    ensure_initialized();
     int allow_bitmapped_fonts = 0, spacing = -1;
     PyObject *ans = NULL;
     FcObjectSet *os = NULL;
@@ -198,6 +218,7 @@ end:
 
 bool
 information_for_font_family(const char *family, bool bold, bool italic, FontConfigFace *ans) {
+    ensure_initialized();
     memset(ans, 0, sizeof(FontConfigFace));
     FcPattern *pat = FcPatternCreate();
     bool ok = false;
@@ -214,6 +235,7 @@ end:
 
 static PyObject*
 fc_match(PyObject UNUSED *self, PyObject *args) {
+    ensure_initialized();
     char *family = NULL;
     int bold = 0, italic = 0, allow_bitmapped_fonts = 0, spacing = FC_MONO;
     double size_in_pts = 0, dpi = 0;
@@ -248,6 +270,7 @@ end:
 
 static PyObject*
 fc_match_postscript_name(PyObject UNUSED *self, PyObject *args) {
+    ensure_initialized();
     const char *postscript_name = NULL;
     FcPattern *pat = NULL;
     PyObject *ans = NULL;
@@ -269,6 +292,7 @@ end:
 
 PyObject*
 specialize_font_descriptor(PyObject *base_descriptor, FONTS_DATA_HANDLE fg) {
+    ensure_initialized();
     PyObject *p = PyDict_GetItemString(base_descriptor, "path"), *ans = NULL;
     PyObject *idx = PyDict_GetItemString(base_descriptor, "index");
     if (p == NULL) { PyErr_SetString(PyExc_ValueError, "Base descriptor has no path"); return NULL; }
@@ -292,6 +316,7 @@ end:
 
 bool
 fallback_font(char_type ch, const char *family, bool bold, bool italic, bool prefer_color, FontConfigFace *ans) {
+    ensure_initialized();
     memset(ans, 0, sizeof(FontConfigFace));
     bool ok = false;
     FcPattern *pat = FcPatternCreate();
@@ -310,6 +335,7 @@ end:
 
 PyObject*
 create_fallback_face(PyObject UNUSED *base_face, CPUCell* cell, bool bold, bool italic, bool emoji_presentation, FONTS_DATA_HANDLE fg) {
+    ensure_initialized();
     PyObject *ans = NULL;
     FcPattern *pat = FcPatternCreate();
     if (pat == NULL) return PyErr_NoMemory();
@@ -336,11 +362,7 @@ static PyMethodDef module_methods[] = {
 
 bool
 init_fontconfig_library(PyObject *module) {
-    if (!FcInit()) {
-        PyErr_SetString(PyExc_RuntimeError, "Failed to initialize the fontconfig library");
-        return false;
-    }
-    register_at_exit_cleanup_func(FONTCONFIG_CLEANUP_FUNC, FcFini);
+    register_at_exit_cleanup_func(FONTCONFIG_CLEANUP_FUNC, finalize);
     if (PyModule_AddFunctions(module, module_methods) != 0) return false;
     PyModule_AddIntMacro(module, FC_WEIGHT_REGULAR);
     PyModule_AddIntMacro(module, FC_WEIGHT_MEDIUM);