1 files changed, 166 insertions, 0 deletions
diff --git a/src/mem_fb.c b/src/mem_fb.c
new file mode 100644
index 0000000..a564c1f
--- /dev/null
+++ b/src/mem_fb.c
@@ -0,0 +1,166 @@
+#include <assert.h>
+#include <stdlib.h>
+
+#include "til_fb.h"
+#include "til_settings.h"
+#include "til_util.h"
+
+/* dummy mem_fb backend; render to anonymous memory */
+/* useful for testing/debugging, and benchmarking systems even if headless */
+
+typedef struct mem_fb_page_t mem_fb_page_t;
+
+struct mem_fb_page_t {
+	void			*unused;
+	uint32_t		buf[];
+};
+
+typedef struct mem_fb_setup_t {
+	til_setup_t		til_setup;
+	unsigned		width, height;
+} mem_fb_setup_t;
+
+typedef struct mem_fb_t {
+	mem_fb_setup_t		setup;
+} mem_fb_t;
+
+
+static int mem_fb_setup(const til_settings_t *settings, til_setting_t **res_setting, const til_setting_desc_t **res_desc, til_setup_t **res_setup)
+{
+	const char	*size;
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Virtual window size",
+							.key = "size",
+							.regex = "[1-9][0-9]*[xX][1-9][0-9]*",
+							.preferred = "640x480",
+							.values = NULL,
+							.annotations = NULL
+						},
+						&size,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	if (res_setup) {
+		mem_fb_setup_t	*setup;
+
+		setup = til_setup_new(sizeof(*setup), (void(*)(til_setup_t *))free);
+		if (!setup)
+			return -ENOMEM;
+
+		/* TODO FIXME: parse errors */
+		sscanf(size, "%ux%u", &setup->width, &setup->height);
+
+		*res_setup = &setup->til_setup;
+	}
+
+	return 0;
+}
+
+
+static int mem_fb_init(const til_setup_t *setup, void **res_context)
+{
+	mem_fb_t	*c;
+	int		r;
+
+	assert(setup);
+	assert(res_context);
+
+	c = calloc(1, sizeof(mem_fb_t));
+	if (!c) {
+		r = -ENOMEM;
+		goto _err;
+	}
+
+	c->setup = *(mem_fb_setup_t *)setup;
+
+	*res_context = c;
+
+	return 0;
+
+_err:
+	return r;
+}
+
+
+static void mem_fb_shutdown(til_fb_t *fb, void *context)
+{
+	mem_fb_t	*c = context;
+
+	assert(c);
+
+	free(c);
+}
+
+
+static int mem_fb_acquire(til_fb_t *fb, void *context, void *page)
+{
+	mem_fb_t	*c = context;
+	mem_fb_page_t	*p = page;
+
+	return 0;
+}
+
+
+static void mem_fb_release(til_fb_t *fb, void *context)
+{
+}
+
+
+static void * mem_fb_page_alloc(til_fb_t *fb, void *context, til_fb_page_t *res_page)
+{
+	mem_fb_t	*c = context;
+	mem_fb_page_t	*p;
+
+	p = calloc(1, sizeof(mem_fb_page_t) + c->setup.width * c->setup.height * sizeof(uint32_t));
+	if (!p)
+		return NULL;
+
+	*res_page =	(til_fb_page_t){
+				.fragment.buf = p->buf,
+				.fragment.width = c->setup.width,
+				.fragment.frame_width = c->setup.width,
+				.fragment.height = c->setup.height,
+				.fragment.frame_height = c->setup.height,
+				.fragment.pitch = c->setup.width,
+			};
+
+	return p;
+}
+
+
+static int mem_fb_page_free(til_fb_t *fb, void *context, void *page)
+{
+	mem_fb_t	*c = context;
+	mem_fb_page_t	*p = page;
+
+	free(p);
+
+	return 0;
+}
+
+
+static int mem_fb_page_flip(til_fb_t *fb, void *context, void *page)
+{
+	mem_fb_t	*c = context;
+	mem_fb_page_t	*p = page;
+
+	/* TODO: add a timer for supporting an fps setting? */
+	return 0;
+}
+
+
+til_fb_ops_t mem_fb_ops = {
+	.setup = mem_fb_setup,
+	.init = mem_fb_init,
+	.shutdown = mem_fb_shutdown,
+	.acquire = mem_fb_acquire,
+	.release = mem_fb_release,
+	.page_alloc = mem_fb_page_alloc,
+	.page_free = mem_fb_page_free,
+	.page_flip = mem_fb_page_flip
+};