tests: Migrate screenshot code from internal test to client helpers

These routines provide test cases an ability to capture screen images
for rendering verification.

This commit is a no-change refactoring, except for making the routines
non-static.  Makefile rules are also updated; most notably, this links
test clients against the cairo libraries now.

v2: Fix pointer code styling, suggested in review

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Derek Foreman <derekf@osg.samsung.com>

3 files changed, 172 insertions, 162 deletions

diff --git a/tests/internal-screenshot-test.c b/tests/internal-screenshot-test.c
index 6b26e1a5..563aa3d3 100644
--- a/tests/internal-screenshot-test.c
+++ b/tests/internal-screenshot-test.c
@@ -25,172 +25,12 @@
 
 #include "config.h"
 
-#include <unistd.h>
 #include <stdio.h>
-#include <string.h> /* memcpy */
-#include <cairo.h>
 
-#include "zalloc.h"
 #include "weston-test-client-helper.h"
 
 char *server_parameters="--use-pixman --width=320 --height=240";
 
-/** write_surface_as_png()
- *
- * Writes out a given weston test surface to disk as a PNG image
- * using the provided filename (with path).
- *
- * @returns true if successfully saved file; false otherwise.
- */
-static bool
-write_surface_as_png(const struct surface* weston_surface, const char *fname)
-{
-	cairo_surface_t *cairo_surface;
-	cairo_status_t status;
-	int bpp = 4; /* Assume ARGB */
-	int stride = bpp * weston_surface->width;
-
-	cairo_surface = cairo_image_surface_create_for_data(weston_surface->data,
-							    CAIRO_FORMAT_ARGB32,
-							    weston_surface->width,
-							    weston_surface->height,
-							    stride);
-	printf("Writing PNG to disk\n");
-	status = cairo_surface_write_to_png(cairo_surface, fname);
-	if (status != CAIRO_STATUS_SUCCESS) {
-		printf("Failed to save screenshot: %s\n",
-		       cairo_status_to_string(status));
-		return false;
-	}
-	cairo_surface_destroy(cairo_surface);
-	return true;
-}
-
-/** load_surface_from_png()
- *
- * Reads a PNG image from disk using the given filename (and path)
- * and returns as a freshly allocated weston test surface.
- *
- * @returns weston test surface with image, which should be free'd
- * when no longer used; or, NULL in case of error.
- */
-static struct surface*
-load_surface_from_png(const char *fname)
-{
-	struct surface *reference;
-	cairo_surface_t *reference_cairo_surface;
-	cairo_status_t status;
-	size_t source_data_size;
-	int bpp;
-	int stride;
-
-	reference_cairo_surface = cairo_image_surface_create_from_png(fname);
-	status = cairo_surface_status(reference_cairo_surface);
-	if (status != CAIRO_STATUS_SUCCESS) {
-		printf("Could not open %s: %s\n", fname, cairo_status_to_string(status));
-		cairo_surface_destroy(reference_cairo_surface);
-		return NULL;
-	}
-
-	/* Disguise the cairo surface in a weston test surface */
-	reference = zalloc(sizeof *reference);
-	if (reference == NULL) {
-		perror("zalloc reference");
-		cairo_surface_destroy(reference_cairo_surface);
-		return NULL;
-	}
-	reference->width = cairo_image_surface_get_width(reference_cairo_surface);
-	reference->height = cairo_image_surface_get_height(reference_cairo_surface);
-	stride = cairo_image_surface_get_stride(reference_cairo_surface);
-	source_data_size = stride * reference->height;
-
-	/* Check that the file's stride matches our assumption */
-	bpp = 4;
-	if (stride != bpp * reference->width) {
-		printf("Mismatched stride for screenshot reference image %s\n", fname);
-		cairo_surface_destroy(reference_cairo_surface);
-		free(reference);
-		return NULL;
-	}
-
-	/* Allocate new buffer for our weston reference, and copy the data from
-	   the cairo surface so we can destroy it */
-	reference->data = zalloc(source_data_size);
-	if (reference->data == NULL) {
-		perror("zalloc reference data");
-		cairo_surface_destroy(reference_cairo_surface);
-		free(reference);
-		return NULL;
-	}
-	memcpy(reference->data,
-	       cairo_image_surface_get_data(reference_cairo_surface),
-	       source_data_size);
-
-	cairo_surface_destroy(reference_cairo_surface);
-	return reference;
-}
-
-/** create_screenshot_surface()
- *
- *  Allocates and initializes a weston test surface for use in
- *  storing a screenshot of the client's output.  Establishes a
- *  shm backed wl_buffer for retrieving screenshot image data
- *  from the server, sized to match the client's output display.
- *
- *  @returns stack allocated surface image, which should be
- *  free'd when done using it.
- */
-static struct surface*
-create_screenshot_surface(struct client *client)
-{
-	struct surface* screenshot;
-	screenshot = zalloc(sizeof *screenshot);
-	if (screenshot == NULL)
-		return NULL;
-	screenshot->wl_buffer = create_shm_buffer(client,
-						  client->output->width,
-						  client->output->height,
-						  &screenshot->data);
-	screenshot->height = client->output->height;
-	screenshot->width = client->output->width;
-
-	return screenshot;
-}
-
-/** capture_screenshot_of_output()
- *
- * Requests a screenshot from the server of the output that the
- * client appears on.  The image data returned from the server
- * can be accessed from the screenshot surface's data member.
- *
- * @returns a new surface object, which should be free'd when no
- * longer needed.
- */
-static struct surface *
-capture_screenshot_of_output(struct client *client)
-{
-	struct surface *screenshot;
-
-	/* Create a surface to hold the screenshot */
-	screenshot = create_screenshot_surface(client);
-
-	client->test->buffer_copy_done = 0;
-	weston_test_capture_screenshot(client->test->weston_test,
-				       client->output->wl_output,
-				       screenshot->wl_buffer);
-	while (client->test->buffer_copy_done == 0)
-		if (wl_display_dispatch(client->wl_display) < 0)
-			break;
-
-	/* FIXME: Document somewhere the orientation the screenshot is taken
-	 * and how the clip coords are interpreted, in case of scaling/transform.
-	 * If we're using read_pixels() just make sure it is documented somewhere.
-	 * Protocol docs in the XML, comparison function docs in Doxygen style.
-	 */
-
-	return screenshot;
-}
-
 static void
 draw_stuff(void *pixels, int w, int h)
 {
diff --git a/tests/weston-test-client-helper.c b/tests/weston-test-client-helper.c
index 65a8880b..16786d9b 100644
--- a/tests/weston-test-client-helper.c
+++ b/tests/weston-test-client-helper.c
@@ -31,7 +31,9 @@
 #include <unistd.h>
 #include <errno.h>
 #include <sys/mman.h>
+#include <cairo.h>
 
+#include "zalloc.h"
 #include "shared/os-compatibility.h"
 #include "weston-test-client-helper.h"
 
@@ -979,3 +981,159 @@ check_surfaces_match_in_clip(const struct surface *a, const struct surface *b, c
 
 	return true;
 }
+
+/** write_surface_as_png()
+ *
+ * Writes out a given weston test surface to disk as a PNG image
+ * using the provided filename (with path).
+ *
+ * @returns true if successfully saved file; false otherwise.
+ */
+bool
+write_surface_as_png(const struct surface *weston_surface, const char *fname)
+{
+	cairo_surface_t *cairo_surface;
+	cairo_status_t status;
+	int bpp = 4; /* Assume ARGB */
+	int stride = bpp * weston_surface->width;
+
+	cairo_surface = cairo_image_surface_create_for_data(weston_surface->data,
+							    CAIRO_FORMAT_ARGB32,
+							    weston_surface->width,
+							    weston_surface->height,
+							    stride);
+	printf("Writing PNG to disk\n");
+	status = cairo_surface_write_to_png(cairo_surface, fname);
+	if (status != CAIRO_STATUS_SUCCESS) {
+		printf("Failed to save screenshot: %s\n",
+		       cairo_status_to_string(status));
+		return false;
+	}
+	cairo_surface_destroy(cairo_surface);
+	return true;
+}
+
+/** load_surface_from_png()
+ *
+ * Reads a PNG image from disk using the given filename (and path)
+ * and returns as a freshly allocated weston test surface.
+ *
+ * @returns weston test surface with image, which should be free'd
+ * when no longer used; or, NULL in case of error.
+ */
+struct surface *
+load_surface_from_png(const char *fname)
+{
+	struct surface *reference;
+	cairo_surface_t *reference_cairo_surface;
+	cairo_status_t status;
+	size_t source_data_size;
+	int bpp;
+	int stride;
+
+	reference_cairo_surface = cairo_image_surface_create_from_png(fname);
+	status = cairo_surface_status(reference_cairo_surface);
+	if (status != CAIRO_STATUS_SUCCESS) {
+		printf("Could not open %s: %s\n", fname, cairo_status_to_string(status));
+		cairo_surface_destroy(reference_cairo_surface);
+		return NULL;
+	}
+
+	/* Disguise the cairo surface in a weston test surface */
+	reference = zalloc(sizeof *reference);
+	if (reference == NULL) {
+		perror("zalloc reference");
+		cairo_surface_destroy(reference_cairo_surface);
+		return NULL;
+	}
+	reference->width = cairo_image_surface_get_width(reference_cairo_surface);
+	reference->height = cairo_image_surface_get_height(reference_cairo_surface);
+	stride = cairo_image_surface_get_stride(reference_cairo_surface);
+	source_data_size = stride * reference->height;
+
+	/* Check that the file's stride matches our assumption */
+	bpp = 4;
+	if (stride != bpp * reference->width) {
+		printf("Mismatched stride for screenshot reference image %s\n", fname);
+		cairo_surface_destroy(reference_cairo_surface);
+		free(reference);
+		return NULL;
+	}
+
+	/* Allocate new buffer for our weston reference, and copy the data from
+	   the cairo surface so we can destroy it */
+	reference->data = zalloc(source_data_size);
+	if (reference->data == NULL) {
+		perror("zalloc reference data");
+		cairo_surface_destroy(reference_cairo_surface);
+		free(reference);
+		return NULL;
+	}
+	memcpy(reference->data,
+	       cairo_image_surface_get_data(reference_cairo_surface),
+	       source_data_size);
+
+	cairo_surface_destroy(reference_cairo_surface);
+	return reference;
+}
+
+/** create_screenshot_surface()
+ *
+ *  Allocates and initializes a weston test surface for use in
+ *  storing a screenshot of the client's output.  Establishes a
+ *  shm backed wl_buffer for retrieving screenshot image data
+ *  from the server, sized to match the client's output display.
+ *
+ *  @returns stack allocated surface image, which should be
+ *  free'd when done using it.
+ */
+struct surface *
+create_screenshot_surface(struct client *client)
+{
+	struct surface *screenshot;
+	screenshot = zalloc(sizeof *screenshot);
+	if (screenshot == NULL)
+		return NULL;
+	screenshot->wl_buffer = create_shm_buffer(client,
+						  client->output->width,
+						  client->output->height,
+						  &screenshot->data);
+	screenshot->height = client->output->height;
+	screenshot->width = client->output->width;
+
+	return screenshot;
+}
+
+/** capture_screenshot_of_output()
+ *
+ * Requests a screenshot from the server of the output that the
+ * client appears on.  The image data returned from the server
+ * can be accessed from the screenshot surface's data member.
+ *
+ * @returns a new surface object, which should be free'd when no
+ * longer needed.
+ */
+struct surface *
+capture_screenshot_of_output(struct client *client)
+{
+	struct surface *screenshot;
+
+	/* Create a surface to hold the screenshot */
+	screenshot = create_screenshot_surface(client);
+
+	client->test->buffer_copy_done = 0;
+	weston_test_capture_screenshot(client->test->weston_test,
+				       client->output->wl_output,
+				       screenshot->wl_buffer);
+	while (client->test->buffer_copy_done == 0)
+		if (wl_display_dispatch(client->wl_display) < 0)
+			break;
+
+	/* FIXME: Document somewhere the orientation the screenshot is taken
+	 * and how the clip coords are interpreted, in case of scaling/transform.
+	 * If we're using read_pixels() just make sure it is documented somewhere.
+	 * Protocol docs in the XML, comparison function docs in Doxygen style.
+	 */
+
+	return screenshot;
+}
diff --git a/tests/weston-test-client-helper.h b/tests/weston-test-client-helper.h
index 7c2727ad..e3ebd1f2 100644
--- a/tests/weston-test-client-helper.h
+++ b/tests/weston-test-client-helper.h
@@ -197,10 +197,10 @@ void
 expect_protocol_error(struct client *client,
 		      const struct wl_interface *intf, uint32_t code);
 
-char*
+char *
 screenshot_output_filename(const char *basename, uint32_t seq);
 
-char*
+char *
 screenshot_reference_filename(const char *basename, uint32_t seq);
 
 bool
@@ -212,4 +212,16 @@ check_surfaces_equal(const struct surface *a, const struct surface *b);
 bool
 check_surfaces_match_in_clip(const struct surface *a, const struct surface *b, const struct rectangle *clip);
 
+bool
+write_surface_as_png(const struct surface *weston_surface, const char *fname);
+
+struct surface *
+load_surface_from_png(const char *fname);
+
+struct surface *
+create_screenshot_surface(struct client *client);
+
+struct surface *
+capture_screenshot_of_output(struct client *client);
+
 #endif