Add the Wayland platform to FLTK 1.4

1 files changed, 127 insertions, 0 deletions

diff --git a/libdecor/build/fl_libdecor.c b/libdecor/build/fl_libdecor.c
new file mode 100644
index 000000000..a09155566
--- /dev/null
+++ b/libdecor/build/fl_libdecor.c
@@ -0,0 +1,127 @@
+//
+// Interface with the libdecor library for the Fast Light Tool Kit (FLTK).
+//
+// Copyright 2022 by Bill Spitzak and others.
+//
+// This library is free software. Distribution and use rights are outlined in
+// the file "COPYING" which should have been included with this file.  If this
+// file is missing or damaged, see the license at:
+//
+//     https://www.fltk.org/COPYING.php
+//
+// Please see the following page on how to report bugs and issues:
+//
+//     https://www.fltk.org/bugs.php
+//
+
+/* Improvements to libdecor.c without modifying libdecor.c itself */
+
+#define libdecor_frame_set_minimized libdecor_frame_set_minimized_orig
+#define libdecor_new libdecor_new_orig
+#include <dlfcn.h>
+static void *dlopen_corrected(const char *, int);
+#define dlopen(A, B) dlopen_corrected(A, B)
+#include "../src/libdecor.c"
+#undef dlopen
+#undef libdecor_frame_set_minimized
+#undef libdecor_new
+
+extern bool fl_libdecor_using_weston(void);
+extern const struct libdecor_plugin_description *fl_libdecor_plugin_description;
+//#include <stdio.h>
+
+// we have a built-in plugin so don't need a fallback one
+struct libdecor_plugin *libdecor_fallback_plugin_new(struct libdecor *context) {
+  return NULL;
+}
+
+// see get_libdecor_plugin_description() explaining why this is useful
+static void *dlopen_corrected(const char *filename, int flags) {
+  static int best_priority = -1;
+  void *retval = dlopen(filename, flags);
+  if (retval) {
+    const struct libdecor_plugin_description *description =
+        (const struct libdecor_plugin_description*)dlsym(retval, "libdecor_plugin_description");
+    if (description && description->priorities->priority > best_priority) {
+        fl_libdecor_plugin_description = description;
+        best_priority = description->priorities->priority;
+    }
+  }
+  return retval;
+}
+
+
+LIBDECOR_EXPORT void libdecor_frame_set_minimized(struct libdecor_frame *frame)
+{
+  static bool done = false;
+  static bool using_weston = false;
+  if (!done) {
+    typedef bool (*ext_f)(void);
+    volatile ext_f ext = fl_libdecor_using_weston;
+    done = true;
+    if (ext) using_weston = fl_libdecor_using_weston();
+//fprintf(stderr, "fl_libdecor_using_weston=%p using_weston=%d\n", fl_libdecor_using_weston, using_weston);
+    if (using_weston) { // determine the version of the running Weston compositor
+      FILE *pipe = popen("weston --version", "r");
+      if (pipe) {
+        char line[50], *p;
+        int version = 0;
+        p = fgets(line, sizeof(line), pipe);
+        pclose(pipe);
+        if (p) p = strchr(line, ' ');
+        if (p) {
+          sscanf(p, "%d", &version);
+          // Weston version 10 has fixed the bug handled here
+          if (version >= 10) using_weston = false;
+        }
+      }
+    }
+  }
+  if (using_weston) libdecor_frame_set_visibility(frame, false);
+  libdecor_frame_set_minimized_orig(frame);
+}
+
+
+/*
+ By default, FLTK modifies libdecor's libdecor_new() function to determine the plugin as follows :
+ 1) the directory pointed by environment variable LIBDECOR_PLUGIN_DIR or, in absence of this variable,
+    by -DLIBDECOR_PLUGIN_DIR=xxx at build time is searched for a libdecor plugin;
+ 2) if this directory does not exist or contains no plugin, the built-in plugin is used.
+    * if FLTK was built with package libgtk-3-dev, the GTK plugin is used
+    * if FLTK was built without package libgtk-3-dev, the Cairo plugin is used
+ 
+ If FLTK was built with OPTION_USE_SYSTEM_LIBDECOR turned ON, the present modification
+ isn't compiled, so the plugin-searching algorithm of libdecor_new() in libdecor-0.so is used.
+ This corresponds to step 1) above and to use no titlebar is no plugin is found.
+ 
+ N.B.: only the system package is built with a meaningful value of -DLIBDECOR_PLUGIN_DIR=
+ so a plugin may be loaded that way only if FLTK was built with OPTION_USE_SYSTEM_LIBDECOR turned ON.
+ 
+ */
+LIBDECOR_EXPORT struct libdecor *libdecor_new(struct wl_display *wl_display, struct libdecor_interface *iface)
+{
+  struct libdecor *context;
+  context = zalloc(sizeof *context);
+  context->ref_count = 1;
+  context->iface = iface;
+  context->wl_display = wl_display;
+  context->wl_registry = wl_display_get_registry(wl_display);
+  wl_registry_add_listener(context->wl_registry, &registry_listener, context);
+  context->init_callback = wl_display_sync(context->wl_display);
+  wl_callback_add_listener(context->init_callback, &init_wl_display_callback_listener, context);
+  wl_list_init(&context->frames);
+  // attempt to dynamically load a libdecor plugin with dlopen()
+  FILE *old_stderr = stderr;
+  stderr = fopen("/dev/null", "w+"); // avoid "Couldn't open plugin directory" messages
+  if (init_plugins(context) != 0) { // attempt to load plugin by dlopen()
+    // no plug-in was found by dlopen(), use built-in plugin instead
+    // defined in the source code of the built-in plugin:  libdecor-cairo.c or libdecor-gtk.c
+    extern const struct libdecor_plugin_description libdecor_plugin_description;
+    context->plugin = libdecor_plugin_description.constructor(context);
+  }
+  fclose(stderr); // restore stderr as it was before
+  stderr = old_stderr;
+
+  wl_display_flush(wl_display);
+  return context;
+}