Add XCB supportHEADmaster

This adds an XCB backend and hooks it up for cairo (not skia... yet).
This is for doing performance comparisons of the GL backend against
"standard Cairo".

7 files changed, 261 insertions, 0 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 62d0482..a140ccc 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -20,6 +20,12 @@ if (USE_EGL)
     )
 endif (USE_EGL)
 
+if (USE_XCB)
+  list(APPEND caskbench_SOURCES
+    xcb.cpp
+    )
+endif (USE_XCB)
+
 if (USE_SKIA)
   file(GLOB skia_files 
     skia-util.cpp
@@ -34,6 +40,9 @@ if (USE_SKIA)
   if (USE_EGL)
     list(APPEND caskbench_SOURCES skia-egl.cpp)
   endif (USE_EGL)
+  if (USE_XCB)
+    list(APPEND caskbench_SOURCES skia-xcb.cpp)
+  endif (USE_XCB)
 endif (USE_SKIA)
 
 if (USE_CAIRO)
@@ -50,6 +59,9 @@ if (USE_CAIRO)
   if (USE_EGL)
     list(APPEND caskbench_SOURCES cairo-egl.cpp)
   endif (USE_EGL)
+  if (USE_XCB)
+    list(APPEND caskbench_SOURCES cairo-xcb.cpp)
+  endif (USE_XCB)
 endif (USE_CAIRO)
 
 add_executable(generate_tests IMPORTED)
diff --git a/src/cairo-xcb.cpp b/src/cairo-xcb.cpp
new file mode 100644
index 0000000..7a67a54
--- /dev/null
+++ b/src/cairo-xcb.cpp
@@ -0,0 +1,82 @@
+/*
+ * Copyright 2017 © Samsung Research America, Silicon Valley
+ *
+ * Use of this source code is governed by the 3-Clause BSD license
+ * specified in the COPYING file included with this source code.
+ */
+#include <config.h>
+
+#include <err.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include <cairo.h>
+#include <cairo-xcb.h>
+
+#include "xcb.h"
+#include "device_config.h"
+
+static xcb_state_t *state;
+static cairo_surface_t *cairo_surface;
+
+cairo_surface_t *
+create_cairo_surface_xcb (const device_config_t& config)
+{
+    // TODO: This needs initted to 0
+    state = (xcb_state_t*) malloc (sizeof (xcb_state_t));
+    if (!state) {
+        warnx ("Out of memory\n");
+        return NULL;
+    }
+
+    if (!createXCBContextAndWindow(state, config.width, config.height)) {
+        cleanup_state_xcb(state);
+        errx (-1, "Could not create XCB context and window\n");
+    }
+
+    assert(state->xcb_window >= 0);
+    assert(state->xcb_connection);
+    assert(state->xcb_visual_type);
+
+    // TODO: Do XCB-specific setup and surface creation
+    cairo_surface = cairo_xcb_surface_create(
+        state->xcb_connection,     // XCB connection
+        state->xcb_window,      // XCB drawable window
+        state->xcb_visual_type, // Visual to use for drawing to window
+        config.width,           // Window width
+        config.height);         // Window height
+
+    // TODO: Set background, clear colors, etc.
+
+    return cairo_surface;
+}
+
+void
+destroy_cairo_xcb(void)
+{
+    cleanup_state_xcb((void*)state);
+
+    cairo_surface_finish(cairo_surface);
+
+    // TODO: Do I need to destroy the surface here, or higher up?  If here, then do I need to track
+    // cairo_surface in state?  Uncommented, this causes a ref count fault, so it appears to
+    // already have been destroyed (maybe by _finish?)
+    //cairo_surface_destroy(cairo_surface);
+}
+
+void
+update_cairo_xcb(void)
+{
+    // TODO
+}
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
diff --git a/src/caskbench.cpp b/src/caskbench.cpp
index 6fe9823..2b12b32 100644
--- a/src/caskbench.cpp
+++ b/src/caskbench.cpp
@@ -113,6 +113,9 @@ print_surfaces_available()
 #if USE_EGL
     printf("egl\n");
 #endif
+#if USE_XCB
+    printf("xcb\n");
+#endif
 }
 
 static void
diff --git a/src/caskbench_context.cpp b/src/caskbench_context.cpp
index 50f9e1d..375d4e1 100644
--- a/src/caskbench_context.cpp
+++ b/src/caskbench_context.cpp
@@ -70,6 +70,14 @@ context_setup_cairo(caskbench_context_t *context, const device_config_t& config)
 #else
         errx(1, "egl unsupported in this build\n");
 #endif
+    } else if (!strncmp(config.surface_type, "xcb", 3)) {
+#if USE_XCB
+        context->setup_cairo = create_cairo_surface_xcb;
+        context->destroy_cairo = destroy_cairo_xcb;
+        context->update_cairo = update_cairo_xcb;
+#else
+        errx(1, "xcb unsupported in this build\n");
+#endif
     }
     assert (context->setup_cairo);
     assert (context->destroy_cairo);
diff --git a/src/caskbench_context.h b/src/caskbench_context.h
index 691afc8..1351d8d 100644
--- a/src/caskbench_context.h
+++ b/src/caskbench_context.h
@@ -68,6 +68,11 @@ void destroy_skia_egl();
 void update_skia_egl();
 #endif
 
+#if USE_XCB
+cairo_surface_t * create_cairo_surface_xcb (const device_config_t& config);
+void destroy_cairo_xcb();
+void update_cairo_xcb();
+#endif
 
 // Context initialization and management
 void context_init(caskbench_context_t *context, int size);
diff --git a/src/xcb.cpp b/src/xcb.cpp
new file mode 100644
index 0000000..4de34da
--- /dev/null
+++ b/src/xcb.cpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2017 © Samsung Research America, Silicon Valley
+ *
+ * Use of this source code is governed by the 3-Clause BSD license
+ * specified in the COPYING file included with this source code.
+ */
+#include <config.h>
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "xcb.h"
+#include "device_config.h"
+
+bool
+createXCBContextAndWindow(xcb_state_t *state, int width, int height)
+{
+    xcb_screen_t *screen;
+    uint32_t mask[2];
+    const xcb_setup_t *setup;
+    xcb_visualtype_t *visual;
+    xcb_generic_event_t *event;
+    xcb_screen_iterator_t screen_iter;
+    xcb_depth_iterator_t depth_iter;
+
+    // Set up XCB
+    state->xcb_connection = xcb_connect(NULL, &state->xcb_screen_number);
+    if (state->xcb_connection == NULL) {
+        warnx("Could not create XCB context\n");
+        return false;
+    } else if (xcb_connection_has_error(state->xcb_connection)) {
+        warnx("Could not connect to X11 server\n");
+        return false;
+    }
+
+    // Set up screen
+    setup = xcb_get_setup(state->xcb_connection);
+    if (setup == NULL) {
+        warnx("Could not create XCB setup\n");
+        return false;
+    }
+    screen_iter = xcb_setup_roots_iterator(setup);
+    for (; screen_iter.rem; --state->xcb_screen_number, xcb_screen_next(&screen_iter)) {
+        if (state->xcb_screen_number == 0) {
+            state->xcb_screen = screen_iter.data;
+            break;
+        }
+    }
+    if (state->xcb_screen == NULL) {
+        warnx("Could not create XCB screen\n");
+        return false;
+    }
+
+    // Create window
+    state->xcb_window = xcb_generate_id(state->xcb_connection);
+    mask[0] = 1;
+    mask[1] = XCB_EVENT_MASK_EXPOSURE;
+    xcb_create_window(state->xcb_connection,             // XCB connection to X11
+                      XCB_COPY_FROM_PARENT,           // Window's depth
+                      state->xcb_window,              // Window ID
+                      state->xcb_screen->root,        // Parent window
+                      20, 20,                         // X, Y position
+                      width,                          // Window width
+                      height,                         // Window height
+                      0,                              // Border width in pixels
+                      XCB_WINDOW_CLASS_INPUT_OUTPUT,  // Behavior class for window
+                      state->xcb_screen->root_visual, // New window's visual id
+                      XCB_CW_OVERRIDE_REDIRECT | XCB_CW_EVENT_MASK,  // Mask type
+                      mask);                          // Mask values list
+    xcb_map_window(state->xcb_connection, state->xcb_window);
+    xcb_flush(state->xcb_connection);
+
+    // Get the visual
+    depth_iter = xcb_screen_allowed_depths_iterator(state->xcb_screen);
+    for (; depth_iter.rem; xcb_depth_next(&depth_iter)) {
+        xcb_visualtype_iterator_t visual_iter;
+
+        visual_iter = xcb_depth_visuals_iterator(depth_iter.data);
+        for (; visual_iter.rem; xcb_visualtype_next(&visual_iter)) {
+            if (state->xcb_screen->root_visual == visual_iter.data->visual_id) {
+                state->xcb_visual_type = visual_iter.data;
+                return true;
+            }
+        }
+    }
+
+    warnx("XCB internal error, could not find visual\n");
+    xcb_disconnect(state->xcb_connection);
+    return false;
+}
+
+void
+destroyXCBContextAndWindow (xcb_state_t *state)
+{
+    xcb_disconnect(state->xcb_connection);
+}
+ 
+void
+cleanup_state_xcb (void *data)
+{
+    xcb_state_t *state = (xcb_state_t*)data;
+    destroyXCBContextAndWindow(state);
+    free(state);
+}
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
diff --git a/src/xcb.h b/src/xcb.h
new file mode 100644
index 0000000..0b807f4
--- /dev/null
+++ b/src/xcb.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2017 © Samsung Research America, Silicon Valley
+ *
+ * Use of this source code is governed by the 3-Clause BSD license
+ * specified in the COPYING file included with this source code.
+ */
+#ifndef XCB_H_    // -*- mode: c++ -*-
+#define XCB_H_
+
+#include <xcb/xcb.h>
+
+typedef struct {
+    int               xcb_screen_number;
+    xcb_screen_t     *xcb_screen;
+    xcb_window_t      xcb_window;
+    xcb_visualtype_t *xcb_visual_type;
+    xcb_connection_t *xcb_connection;
+} xcb_state_t;
+
+bool createXCBContextAndWindow(xcb_state_t *state, int width, int height);
+void destroyXCBContextAndWindow(xcb_state_t *state);
+void cleanup_state_xcb(void *state);
+
+#endif // XCB_H_
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :