Add the Wayland platform to FLTK 1.4

1 files changed, 348 insertions, 0 deletions

diff --git a/libdecor/build/fl_libdecor-plugins.c b/libdecor/build/fl_libdecor-plugins.c
new file mode 100644
index 000000000..ff8d5a101
--- /dev/null
+++ b/libdecor/build/fl_libdecor-plugins.c
@@ -0,0 +1,348 @@
+//
+// 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
+//
+
+/* Support of interactions between FLTK and libdecor plugins, either dynamically
+ loaded by dlopen() or built-in FLTK.
+ 
+ Under USE_SYSTEM_LIBDECOR, the plugin can only be dynamically loaded.
+ Under ! USE_SYSTEM_LIBDECOR, it can be dynamically loaded from a directory
+ given in environment variable LIBDECOR_PLUGIN_DIR, or the built-in one is used.
+ */
+
+#include <dlfcn.h>
+#include <string.h>
+#include "../src/libdecor.h"
+#include "xdg-decoration-client-protocol.h"
+#include <pango/pangocairo.h>
+
+#if USE_SYSTEM_LIBDECOR
+#include "../src/libdecor-plugin.h"
+
+enum component {NONE};
+enum decoration_type {DECORATION_TYPE_NONE};
+
+struct buffer { // identical in libdecor-cairo.c and libdecor-gtk.c
+  struct wl_buffer *wl_buffer;
+  bool in_use;
+  bool is_detached;
+
+  void *data;
+  size_t data_size;
+  int width;
+  int height;
+  int scale;
+  int buffer_width;
+  int buffer_height;
+};
+
+#else // !USE_SYSTEM_LIBDECOR
+
+const struct libdecor_plugin_description *fl_libdecor_plugin_description = NULL;
+
+#  ifdef HAVE_GTK
+#    include <gtk/gtk.h>
+#    include "../src/plugins/gtk/libdecor-gtk.c"
+#  else
+#    include "../src/plugins/cairo/libdecor-cairo.c"
+#    undef libdecor_frame_set_min_content_size
+#  endif // HAVE_GTK
+
+#endif // USE_SYSTEM_LIBDECOR
+
+
+#if USE_SYSTEM_LIBDECOR || HAVE_GTK
+/* these definitions derive from libdecor/src/plugins/cairo/libdecor-cairo.c */
+
+struct libdecor_plugin_cairo {
+  struct libdecor_plugin plugin;
+
+  struct wl_callback *globals_callback;
+  struct wl_callback *globals_callback_shm;
+
+  struct libdecor *context;
+
+  struct wl_registry *wl_registry;
+  struct wl_subcompositor *wl_subcompositor;
+  struct wl_compositor *wl_compositor;
+
+  struct wl_shm *wl_shm;
+  struct wl_callback *shm_callback;
+  bool has_argb;
+
+  struct wl_list visible_frame_list;
+  struct wl_list seat_list;
+  struct wl_list output_list;
+
+  char *cursor_theme_name;
+  int cursor_size;
+
+  PangoFontDescription *font;
+};
+
+enum composite_mode {
+  COMPOSITE_SERVER,
+  COMPOSITE_CLIENT,
+};
+
+struct border_component_cairo {
+  enum component type;
+
+  bool is_hidden;
+  bool opaque;
+
+  enum composite_mode composite_mode;
+  struct {
+    struct wl_surface *wl_surface;
+    struct wl_subsurface *wl_subsurface;
+    struct buffer *buffer;
+    struct wl_list output_list;
+    int scale;
+  } server;
+  struct {
+    cairo_surface_t *image;
+    struct border_component_cairo *parent_component;
+  } client;
+
+  struct wl_list child_components; /* border_component::link */
+  struct wl_list link; /* border_component::child_components */
+};
+
+struct libdecor_frame_cairo {
+  struct libdecor_frame frame;
+
+  struct libdecor_plugin_cairo *plugin_cairo;
+
+  int content_width;
+  int content_height;
+
+  enum decoration_type decoration_type;
+
+  enum libdecor_window_state window_state;
+
+  char *title;
+
+  enum libdecor_capabilities capabilities;
+
+  struct border_component_cairo *focus;
+  struct border_component_cairo *active;
+  struct border_component_cairo *grab;
+
+  bool shadow_showing;
+  struct border_component_cairo shadow;
+
+  struct {
+    bool is_showing;
+    struct border_component_cairo title;
+    struct border_component_cairo min;
+    struct border_component_cairo max;
+    struct border_component_cairo close;
+  } title_bar;
+
+  /* store pre-processed shadow tile */
+  cairo_surface_t *shadow_blur;
+
+  struct wl_list link;
+};
+#endif
+
+
+#if USE_SYSTEM_LIBDECOR || !HAVE_GTK
+
+/* Definitions derived from libdecor-gtk.c */
+
+typedef struct _GtkWidget GtkWidget;
+enum header_element { HDR_NONE };
+typedef enum { GTK_STATE_FLAG_NORMAL = 0 } GtkStateFlags;
+
+struct border_component_gtk {
+  enum component type;
+  struct wl_surface *wl_surface;
+  struct wl_subsurface *wl_subsurface;
+  struct buffer *buffer;
+  bool opaque;
+  struct wl_list output_list;
+  int scale;
+  struct wl_list child_components; /* border_component::link */
+  struct wl_list link; /* border_component::child_components */
+};
+
+struct header_element_data {
+  const char* name;
+  enum header_element type;
+  GtkWidget *widget;
+  GtkStateFlags state;
+};
+
+struct libdecor_frame_gtk {
+  struct libdecor_frame frame;
+  struct libdecor_plugin_gtk *plugin_gtk;
+  int content_width;
+  int content_height;
+  enum libdecor_window_state window_state;
+  enum decoration_type decoration_type;
+  char *title;
+  enum libdecor_capabilities capabilities;
+  struct border_component_gtk *active;
+  struct border_component_gtk *focus;
+  struct border_component_gtk *grab;
+  bool shadow_showing;
+  struct border_component_gtk shadow;
+  GtkWidget *window; /* offscreen window for rendering */
+  GtkWidget *header; /* header bar with widgets */
+  struct border_component_gtk headerbar;
+  struct header_element_data hdr_focus;
+  cairo_surface_t *shadow_blur;
+  struct wl_list link;
+};
+
+#endif // USE_SYSTEM_LIBDECOR || !HAVE_GTK
+
+/* these definitions are copied from libdecor/src/libdecor.c */
+
+struct libdecor_limits {
+  int min_width;
+  int min_height;
+  int max_width;
+  int max_height;
+};
+
+struct libdecor_frame_private {
+  int ref_count;
+  struct libdecor *context;
+  struct wl_surface *wl_surface;
+  struct libdecor_frame_interface *iface;
+  void *user_data;
+  struct xdg_surface *xdg_surface;
+  struct xdg_toplevel *xdg_toplevel;
+  struct zxdg_toplevel_decoration_v1 *toplevel_decoration;
+  bool pending_map;
+  struct {
+    char *app_id;
+    char *title;
+    struct libdecor_limits content_limits;
+    struct xdg_toplevel *parent;
+  } state;
+  struct libdecor_configuration *pending_configuration;
+  int content_width;
+  int content_height;
+  enum libdecor_window_state window_state;
+  enum zxdg_toplevel_decoration_v1_mode decoration_mode;
+  enum libdecor_capabilities capabilities;
+  struct libdecor_limits interactive_limits;
+  bool visible;
+};
+
+
+static unsigned char *gtk_titlebar_buffer(struct libdecor_frame *frame,
+                                                 int *width, int *height, int *stride)
+{
+  struct libdecor_frame_gtk *lfg = (struct libdecor_frame_gtk *)frame;
+#if USE_SYSTEM_LIBDECOR || !HAVE_GTK
+  struct border_component_gtk *bc;
+#else
+  struct border_component *bc;
+#endif
+  bc = &lfg->headerbar;
+  struct buffer *buffer = bc->buffer;
+  *width = buffer->buffer_width;
+  *height = buffer->buffer_height;
+  *stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, buffer->buffer_width);
+  return (unsigned char*)buffer->data;
+}
+
+
+static unsigned char *cairo_titlebar_buffer(struct libdecor_frame *frame,
+                                                 int *width, int *height, int *stride)
+{
+  struct libdecor_frame_cairo *lfc = (struct libdecor_frame_cairo *)frame;
+#if USE_SYSTEM_LIBDECOR || HAVE_GTK
+  struct border_component_cairo *bc = &lfc->title_bar.title;
+#else
+  struct border_component *bc = &lfc->title_bar.title;
+#endif
+  struct buffer *buffer = bc->server.buffer;
+  *width = buffer->buffer_width;
+  *height = buffer->buffer_height;
+  *stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, buffer->buffer_width);
+  return (unsigned char*)buffer->data;
+}
+
+
+/*
+ Although each plugin declares an exported global variable
+ LIBDECOR_EXPORT const struct libdecor_plugin_description libdecor_plugin_description;
+ these plugins are dlopen()'ed in libdecor.c without the RTLD_GLOBAL flag.
+ Consequently their symbols are not discovered by dlsym(RTLD_DEFAULT, "symbol-name").
+ 
+ Under USE_SYSTEM_LIBDECOR, we repeat the dlopen() for the same plugin
+ then dlsym() will report the address of libdecor_plugin_description.
+ 
+ Under !USE_SYSTEM_LIBDECOR, we compile fl_libdecor.c which modifies the dlopen()
+ to call dlsym(ld, "libdecor_plugin_description") just after the dlopen and memorizes
+ this address.
+ 
+ A plugin is loaded also if SSD.
+ KDE has its own size limit, similar to that of GDK plugin
+ */
+static const char *get_libdecor_plugin_description(struct libdecor_frame *frame) {
+  static const struct libdecor_plugin_description *plugin_description = NULL;
+  if (frame->priv->decoration_mode == ZXDG_TOPLEVEL_DECORATION_V1_MODE_SERVER_SIDE) {
+    return "Server-Side Decoration";
+  }
+   if (!plugin_description) {
+ #if USE_SYSTEM_LIBDECOR
+     char fname[PATH_MAX];
+     const char *dir = getenv("LIBDECOR_PLUGIN_DIR");
+     if (!dir) dir = LIBDECOR_PLUGIN_DIR;
+     sprintf(fname, "%s/libdecor-gtk.so", dir);
+     void *dl = dlopen(fname, RTLD_LAZY | RTLD_LOCAL);
+     if (!dl) {
+       sprintf(fname, "%s/libdecor-cairo.so", dir);
+       dl = dlopen(fname, RTLD_LAZY | RTLD_LOCAL);
+     }
+     if (dl) plugin_description = (const struct libdecor_plugin_description*)dlsym(dl, "libdecor_plugin_description");
+#else
+     plugin_description = fl_libdecor_plugin_description;
+     extern const struct libdecor_plugin_description libdecor_plugin_description;
+     if (!plugin_description) plugin_description = &libdecor_plugin_description;
+#endif
+     //if (plugin_description) puts(plugin_description->description);
+  }
+  return plugin_description ? plugin_description->description : NULL;
+}
+
+
+/*
+ FLTK-added utility function to give access to the pixel array representing
+ the titlebar of a window decorated by the cairo plugin of libdecor.
+   frame: a libdecor-defined pointer given by fl_xid(win)->frame (with Fl_Window *win);
+   *width, *height: returned assigned to the width and height in pixels of the titlebar;
+   *stride: returned assigned to the number of bytes per line of the pixel array;
+   return value: start of the pixel array, which is in BGRA order, or NULL.
+ */
+unsigned char *fl_libdecor_titlebar_buffer(struct libdecor_frame *frame,
+                                                 int *width, int *height, int *stride)
+{
+  static const char *my_plugin = NULL;
+  if (!my_plugin) my_plugin = get_libdecor_plugin_description(frame);
+  if (my_plugin && !strcmp(my_plugin, "GTK plugin")) {
+    return gtk_titlebar_buffer(frame, width, height, stride);
+  }
+  else if (my_plugin && !strcmp(my_plugin, "libdecor plugin using Cairo")) {
+    return cairo_titlebar_buffer(frame, width, height, stride);
+  }
+  return NULL;
+}