summaryrefslogtreecommitdiff
path: root/docs/core-window-interface.md
diff options
context:
space:
mode:
Diffstat (limited to 'docs/core-window-interface.md')
-rw-r--r--docs/core-window-interface.md677
1 files changed, 677 insertions, 0 deletions
diff --git a/docs/core-window-interface.md b/docs/core-window-interface.md
new file mode 100644
index 000000000..09c29990d
--- /dev/null
+++ b/docs/core-window-interface.md
@@ -0,0 +1,677 @@
+Core Window Interface
+=====================
+
+The NetSurf core provides an optional API to frontend implementations
+which allows a number of "standard" window content interfaces to be
+provided.
+
+The currently available user interfaces are:
+
+ - Cookies
+ - Global history
+ - Hotlist
+ - SSL certificate view
+ - local history
+
+Although not currently included in future additional user interfaces
+will be available for the main browser render.
+
+To be clear these are generic implementations of this functionality
+that any frontend may use. Frontends are free to implement these
+interfaces in any manner as they see fit, the corewindow interface
+simply provides a default.
+
+core window API
+---------------
+
+The API is fairly simple and simply involves passing a callback table
+and context pointer to the interface element being constructed.
+
+The header that defines the callback interface is netsurf/core_window.h
+
+The callback table contains five function pointer interfaces which the
+frontend must implement for the core.
+
+ - invalidate
+ invalidate an area of a window
+
+ - update_size
+ Update the limits of the window
+
+ - scroll_visible
+ Scroll the window to make area visible
+
+ - get_window_dimensions
+ Get window viewport dimensions
+
+ - drag_status
+ Inform corewindow owner of drag status
+
+Each callback will be passed the context pointer for the corewindow
+instance and the relevant additional information necessary to perform
+the operation.
+
+Each exported user interface element wraps this generic interface with
+a concrete implementation. For example the SSL certificate viewer is
+initialised with:
+
+ nserror sslcert_viewer_init(struct core_window_callback_table *cw_t,
+ void *core_window_handle,
+ struct sslcert_session_data *ssl_d);
+
+This call creates a context which will display and navigate the ssl
+session data passed. The frontend must service the callbacks from the
+core to provide the necessary interactions with the frontend windowing
+system.
+
+These actions should ideally use the standard frontend window
+processing. So for the GTK frontend when the core calls the invalidate
+operation it simply marks the area passed as damaged (using
+gtk_widget_queue_draw_area()) and lets the standard expose event cause
+the redraw to occur.
+
+If the frontend needs to redraw an area of a window (perhaps an expose
+event occurred or the window has had an area marked as invalid) it
+must call the core window API wrappers implementation which will
+perform the plot operations required to update an area of the window.
+
+e.g in the case of ssl certificate viewer
+
+ void sslcert_viewer_redraw(struct sslcert_session_data *ssl_d,
+ int x, int y, struct rect *clip,
+ const struct redraw_context *ctx);
+
+would perform the plot operations for that SSL data window.
+
+Usage
+-----
+
+The usage pattern that is expected is for a frontend to create a core
+window implementation that implements the necessary five API in a
+generic way and allows the frontend to provide the specific
+specialisation for each of the user interface elements it wishes to
+use (cookies, SSL viewer etc).
+
+The GTK frontend for example:
+
+has source corewindow.[ch] which implement the five core callbacks
+using generic GTK operations (invalidate calls
+gtk_widget_queue_draw_area() etc.) and then provides additional
+operations on a GTK drawing area object to attach expose event
+processing, keypress processing etc.
+
+The GTK corewindow (not to be confused with the core window API
+itself, this is purely the gtk wrapper) is used by ssl_cert.c which
+creates a nsgtk_crtvrfy_window structure containing the
+nsgtk_corewindow structure. It attaches actual GTK window handles to
+this structure and populates elements of nsgtk_corewindow and then
+calls sslcert_viewer_init() directly.
+
+frontend skeleton
+-----------------
+
+An example core window implementation for a frontend ssl certificate
+viewer is presented here. This implements the suggested usage above
+and provides generic corewindow helpers.
+
+
+frontends/example/corewindow.h
+------------------------------
+
+ /*
+ * Copyright 2016 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+ #ifndef EXAMPLE_COREWINDOW_H
+ #define EXAMPLE_COREWINDOW_H
+
+ #include "netsurf/core_window.h"
+
+ /**
+ * example core window state
+ */
+ struct example_corewindow {
+
+
+ /*
+ * Any variables common to any frontend window would go here.
+ * e.g. drawing area handles, toolkit pointers or other state
+ */
+ example_toolkit_widget *tk_widget;
+
+
+
+ /** drag status set by core */
+ core_window_drag_status drag_staus;
+
+ /** table of callbacks for core window operations */
+ struct core_window_callback_table *cb_table;
+
+ /**
+ * callback to draw on drawable area of example core window
+ *
+ * \param example_cw The example core window structure.
+ * \param r The rectangle of the window that needs updating.
+ * \return NSERROR_OK on success otherwise apropriate error code
+ */
+ nserror (*draw)(struct example_corewindow *example_cw, struct rect *r);
+
+ /**
+ * callback for keypress on example core window
+ *
+ * \param example_cw The example core window structure.
+ * \param nskey The netsurf key code.
+ * \return NSERROR_OK if key processed,
+ * NSERROR_NOT_IMPLEMENTED if key not processed
+ * otherwise apropriate error code
+ */
+ nserror (*key)(struct example_corewindow *example_cw, uint32_t nskey);
+
+ /**
+ * callback for mouse event on example core window
+ *
+ * \param example_cw The example core window structure.
+ * \param mouse_state mouse state
+ * \param x location of event
+ * \param y location of event
+ * \return NSERROR_OK on sucess otherwise apropriate error code.
+ */
+ nserror (*mouse)(struct example_corewindow *example_cw, browser_mouse_state mouse_state, int x, int y);
+ };
+
+ /**
+ * initialise elements of example core window.
+ *
+ * As a pre-requisite the draw, key and mouse callbacks must be defined
+ *
+ * \param example_cw A example core window structure to initialise
+ * \return NSERROR_OK on successful initialisation otherwise error code.
+ */
+ nserror example_corewindow_init(struct example_corewindow *example_cw);
+
+ /**
+ * finalise elements of example core window.
+ *
+ * \param example_cw A example core window structure to initialise
+ * \return NSERROR_OK on successful finalisation otherwise error code.
+ */
+ nserror example_corewindow_fini(struct example_corewindow *example_cw);
+
+ #endif
+
+frontends/example/corewindow.c
+------------------------------
+
+ /*
+ * Copyright 2016 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+ /**
+ * file
+ * EXAMPLE generic core window interface.
+ *
+ * Provides interface for core renderers to the example toolkit drawable area.
+ *
+ * This module is an object that must be encapsulated. Client users
+ * should embed a struct example_corewindow at the beginning of their
+ * context for this display surface, fill in relevant data and then
+ * call example_corewindow_init()
+ *
+ * The example core window structure requires the callback for draw, key and
+ * mouse operations.
+ */
+
+ #include <assert.h>
+ #include <string.h>
+ #include <math.h>
+
+ #include "utils/log.h"
+ #include "utils/utils.h"
+ #include "utils/messages.h"
+ #include "utils/utf8.h"
+ #include "netsurf/keypress.h"
+ #include "netsurf/mouse.h"
+ #include "netsurf/plot_style.h"
+
+ /* extremely likely there will be additional headers required in a real frontend */
+ #include "example/corewindow.h"
+
+
+ /* toolkit event handlers that do generic things and call internal callbacks */
+
+
+ static bool
+ example_cw_mouse_press_event(toolkit_widget *widget, toolkit_button bt, int x, int y, void *ctx)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)ctx;
+
+ example_cw->mouse(example_cw, state, x, y);
+
+ return true;
+ }
+
+ static bool
+ example_cw_keyrelease_event(toolkit_widget *widget, void *ctx)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)ctx;
+
+ example_cw->key(example_cw, keycode);
+
+ return true;
+ }
+
+
+
+ /* signal handler for toolkit window redraw */
+ static bool
+ example_cw_draw_event(toolkit_widget *widget,
+ toolkit_area *tk_area,
+ void *ctx)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)ctx;
+ struct rect clip;
+
+ clip.x0 = tk_area.x;
+ clip.y0 = tk_area.y;
+ clip.x1 = tk_area.width;
+ clip.y1 = tk_area.height;
+
+ example_cw->draw(example_cw, &clip);
+
+ return true;
+ }
+
+
+ /**
+ * callback from core to request a redraw
+ */
+ static nserror
+ example_cw_invalidate(struct core_window *cw, const struct rect *r)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)cw;
+
+ toolkit_widget_queue_draw_area(example_cw->widget,
+ r->x0, r->y0,
+ r->x1 - r->x0, r->y1 - r->y0);
+ }
+
+
+ static void
+ example_cw_update_size(struct core_window *cw, int width, int height)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)cw;
+
+ toolkit_widget_set_size_request(EXAMPLE_WIDGET(example_cw->drawing_area),
+ width, height);
+ }
+
+
+ static void
+ example_cw_scroll_visible(struct core_window *cw, const struct rect *r)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)cw;
+
+ toolkit_scroll_widget(example_cw->widget, r);
+ }
+
+
+ static void
+ example_cw_get_window_dimensions(struct core_window *cw, int *width, int *height)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)cw;
+
+ *width = toolkit_get_widget_width(example_cw->widget);
+ *height = toolkit_get_widget_height(example_cw->widget);
+ }
+
+
+ static void
+ example_cw_drag_status(struct core_window *cw, core_window_drag_status ds)
+ {
+ struct example_corewindow *example_cw = (struct example_corewindow *)cw;
+ example_cw->drag_staus = ds;
+ }
+
+
+ struct core_window_callback_table example_cw_cb_table = {
+ .invalidate = example_cw_invalidate,
+ .update_size = example_cw_update_size,
+ .scroll_visible = example_cw_scroll_visible,
+ .get_window_dimensions = example_cw_get_window_dimensions,
+ .drag_status = example_cw_drag_status
+ };
+
+ /* exported function documented example/corewindow.h */
+ nserror example_corewindow_init(struct example_corewindow *example_cw)
+ {
+ /* setup the core window callback table */
+ example_cw->cb_table = &example_cw_cb_table;
+
+ /* frontend toolkit specific method of causing example_cw_draw_event to be called when a drawing operation is required */
+ toolkit_connect_draw_event(example_cw->tk_widget,
+ example_cw_draw_event,
+ example_cw);
+
+ /* frontend toolkit specific method of causing example_cw_button_press_event to be called when a button press occours */
+ toolkit_connect_button_press_event(example_cw->tk_widget,
+ example_cw_button_press_event,
+ example_cw);
+
+ /* frontend toolkit specific method of causing example_cw_button_release_event to be called when a button release occours */
+ toolkit_connect_button_release_event(example_cw->tk_widget,
+ example_cw_button_release_event,
+ example_cw);
+
+ /* frontend toolkit specific method of causing example_cw_motion_notify_event to be called when there is motion over the widget */
+ toolkit_connect_motion_event(example_cw->tk_widget,
+ example_cw_motion_notify_event,
+ example_cw);
+
+ /* frontend toolkit specific method of causing example_cw_key_press_event to be called when a key press occours */
+ toolkit_connect_button_press_event(example_cw->tk_widget,
+ example_cw_key_press_event,
+ example_cw);
+
+ /* frontend toolkit specific method of causing example_cw_key_release_event to be called when a key release occours */
+ toolkit_connect_button_release_event(example_cw->tk_widget,
+ example_cw_key_release_event,
+ example_cw);
+
+
+ return NSERROR_OK;
+ }
+
+ /* exported interface documented in example/corewindow.h */
+ nserror example_corewindow_fini(struct example_corewindow *example_cw)
+ {
+ return NSERROR_OK;
+ }
+
+
+frontends/example/ssl_cert.h
+----------------------------
+
+ /*
+ * Copyright 2016 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+ #ifndef NETSURF_EXAMPLE_SSL_CERT_H
+ #define NETSURF_EXAMPLE_SSL_CERT_H 1
+
+ struct nsurl;
+ struct ssl_cert_info;
+
+ /**
+ * Prompt the user to verify a certificate with issuse.
+ *
+ * \param url The URL being verified.
+ * \param certs The certificate to be verified
+ * \param num The number of certificates to be verified.
+ * \param cb Callback upon user decision.
+ * \param cbpw Context pointer passed to cb
+ * \return NSERROR_OK or error code if prompt creation failed.
+ */
+ nserror example_cert_verify(struct nsurl *url, const struct ssl_cert_info *certs, unsigned long num, nserror (*cb)(bool proceed, void *pw), void *cbpw);
+
+ #endif
+
+frontends/example/ssl_cert.c
+----------------------------
+
+ /*
+ * Copyright 2015 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+ /**
+ * file
+ * Implementation of example certificate viewing using example core windows.
+ */
+
+ #include <stdint.h>
+ #include <stdlib.h>
+
+ #include "utils/log.h"
+ #include "netsurf/keypress.h"
+ #include "netsurf/plotters.h"
+ #include "desktop/sslcert_viewer.h"
+
+ #include "example/corewindow.h"
+
+
+ /**
+ * EXAMPLE certificate viewing window context
+ */
+ struct example_crtvrfy_window {
+ /** example core window context */
+ struct example_corewindow core;
+
+ /** SSL certificate viewer context data */
+ struct sslcert_session_data *ssl_data;
+ };
+
+ /**
+ * destroy a previously created certificate view
+ */
+ static nserror example_crtvrfy_destroy(struct example_crtvrfy_window *crtvrfy_win)
+ {
+ nserror res;
+
+ res = sslcert_viewer_fini(crtvrfy_win->ssl_data);
+ if (res == NSERROR_OK) {
+ res = example_corewindow_fini(&crtvrfy_win->core);
+ toolkit_windown_destroy(crtvrfy_win->window);
+ free(crtvrfy_win);
+ }
+ return res;
+ }
+
+ static void
+ example_crtvrfy_accept(ExampleButton *w, gpointer data)
+ {
+ struct example_crtvrfy_window *crtvrfy_win;
+ crtvrfy_win = (struct example_crtvrfy_window *)data;
+
+ sslcert_viewer_accept(crtvrfy_win->ssl_data);
+
+ example_crtvrfy_destroy(crtvrfy_win);
+ }
+
+ static void
+ example_crtvrfy_reject(ExampleWidget *w, gpointer data)
+ {
+ struct example_crtvrfy_window *crtvrfy_win;
+ crtvrfy_win = (struct example_crtvrfy_window *)data;
+
+ sslcert_viewer_reject(crtvrfy_win->ssl_data);
+
+ example_crtvrfy_destroy(crtvrfy_win);
+ }
+
+
+ /**
+ * callback for mouse action for certificate verify on core window
+ *
+ * \param example_cw The example core window structure.
+ * \param mouse_state netsurf mouse state on event
+ * \param x location of event
+ * \param y location of event
+ * \return NSERROR_OK on success otherwise apropriate error code
+ */
+ static nserror
+ example_crtvrfy_mouse(struct example_corewindow *example_cw,
+ browser_mouse_state mouse_state,
+ int x, int y)
+ {
+ struct example_crtvrfy_window *crtvrfy_win;
+ /* technically degenerate container of */
+ crtvrfy_win = (struct example_crtvrfy_window *)example_cw;
+
+ sslcert_viewer_mouse_action(crtvrfy_win->ssl_data, mouse_state, x, y);
+
+ return NSERROR_OK;
+ }
+
+ /**
+ * callback for keypress for certificate verify on core window
+ *
+ * \param example_cw The example core window structure.
+ * \param nskey The netsurf key code
+ * \return NSERROR_OK on success otherwise apropriate error code
+ */
+ static nserror
+ example_crtvrfy_key(struct example_corewindow *example_cw, uint32_t nskey)
+ {
+ struct example_crtvrfy_window *crtvrfy_win;
+
+ /* technically degenerate container of */
+ crtvrfy_win = (struct example_crtvrfy_window *)example_cw;
+
+ if (sslcert_viewer_keypress(crtvrfy_win->ssl_data, nskey)) {
+ return NSERROR_OK;
+ }
+ return NSERROR_NOT_IMPLEMENTED;
+ }
+
+ /**
+ * callback on draw event for certificate verify on core window
+ *
+ * \param example_cw The example core window structure.
+ * \param r The rectangle of the window that needs updating.
+ * \return NSERROR_OK on success otherwise apropriate error code
+ */
+ static nserror
+ example_crtvrfy_draw(struct example_corewindow *example_cw, struct rect *r)
+ {
+ struct redraw_context ctx = {
+ .interactive = true,
+ .background_images = true,
+ .plot = &example_plotters
+ };
+ struct example_crtvrfy_window *crtvrfy_win;
+
+ /* technically degenerate container of */
+ crtvrfy_win = (struct example_crtvrfy_window *)example_cw;
+
+ sslcert_viewer_redraw(crtvrfy_win->ssl_data, 0, 0, r, &ctx);
+
+ return NSERROR_OK;
+ }
+
+ /* exported interface documented in example/ssl_cert.h */
+ nserror example_cert_verify(struct nsurl *url,
+ const struct ssl_cert_info *certs,
+ unsigned long num,
+ nserror (*cb)(bool proceed, void *pw),
+ void *cbpw)
+ {
+ struct example_crtvrfy_window *ncwin;
+ nserror res;
+
+ ncwin = malloc(sizeof(struct example_crtvrfy_window));
+ if (ncwin == NULL) {
+ return NSERROR_NOMEM;
+ }
+
+ res = toolkit_create_window(&ncwin->window);
+ if (res != NSERROR_OK) {
+ LOG("SSL UI builder init failed");
+ free(ncwin);
+ return res;
+ }
+
+ /* store the widget that the toolkit is drawing into */
+ ncwin->core.widget = toolkit_get_widget(ncwin->window, "SSLDrawingArea"));
+
+ /* would typicaly setup toolkit accept/reject buttons etc. here */
+ toolkit_connect_button_press(ncwin->tk_accept_button,
+ example_crtvrfy_accept,
+ ncwin);
+
+
+ /* initialise example core window */
+ ncwin->core.draw = example_crtvrfy_draw;
+ ncwin->core.key = example_crtvrfy_key;
+ ncwin->core.mouse = example_crtvrfy_mouse;
+
+ res = example_corewindow_init(&ncwin->core);
+ if (res != NSERROR_OK) {
+ free(ncwin);
+ return res;
+ }
+
+ /* initialise certificate viewing interface */
+ res = sslcert_viewer_create_session_data(num, url, cb, cbpw, certs,
+ &ncwin->ssl_data);
+ if (res != NSERROR_OK) {
+ free(ncwin);
+ return res;
+ }
+
+ res = sslcert_viewer_init(ncwin->core.cb_table,
+ (struct core_window *)ncwin,
+ ncwin->ssl_data);
+ if (res != NSERROR_OK) {
+ free(ncwin);
+ return res;
+ }
+
+ toolkit_widget_show(ncwin->window);
+
+ return NSERROR_OK;
+ }