Add a basic benchmarking tool

fastiv-io-benchmark.c

@@ -0,0 +1,65 @@
+//
+// fastiv-io-benchmark.c: see if we're worth the name
+//
+// Copyright (c) 2021, Přemysl Eric Janouch <p@janouch.name>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+#include <time.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+#include "fastiv-view.h"
+
+static double
+timestamp(void)
+{
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	return ts.tv_sec + ts.tv_nsec / 1.e9;
+}
+
+static void
+one_file(const char *filename)
+{
+	double since_us = timestamp();
+	cairo_surface_t *loaded_by_us = fastiv_io_open(filename, NULL);
+	if (!loaded_by_us)
+		return;
+
+	cairo_surface_destroy(loaded_by_us);
+	double us = timestamp() - since_us;
+
+	double since_pixbuf = timestamp();
+	GdkPixbuf *gdk_pixbuf = gdk_pixbuf_new_from_file(filename, NULL);
+	if (!gdk_pixbuf)
+		return;
+
+	cairo_surface_t *loaded_by_pixbuf =
+		gdk_cairo_surface_create_from_pixbuf(gdk_pixbuf, 1, NULL);
+	g_object_unref(gdk_pixbuf);
+	cairo_surface_destroy(loaded_by_pixbuf);
+	double pixbuf = timestamp() - since_pixbuf;
+
+	printf("%f\t%f\t%.0f%%\t%s\n", us, pixbuf, us / pixbuf * 100, filename);
+}
+
+int
+main(int argc, char *argv[])
+{
+	// Needed for gdk_cairo_surface_create_from_pixbuf().
+	gdk_init(&argc, &argv);
+
+	for (int i = 1; i < argc; i++)
+		one_file(argv[i]);
+	return 0;
+}

fastiv-io.c

@@ -0,0 +1,426 @@
+//
+// fastiv-io.c: image loaders
+//
+// Copyright (c) 2021, Přemysl Eric Janouch <p@janouch.name>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+#include "config.h"
+
+#include <glib.h>
+#include <cairo.h>
+#include <turbojpeg.h>
+#ifdef HAVE_LIBRAW
+#include <libraw.h>
+#endif  // HAVE_LIBRAW
+
+#define WUFFS_IMPLEMENTATION
+#define WUFFS_CONFIG__MODULES
+#define WUFFS_CONFIG__MODULE__ADLER32
+#define WUFFS_CONFIG__MODULE__BASE
+#define WUFFS_CONFIG__MODULE__BMP
+#define WUFFS_CONFIG__MODULE__CRC32
+#define WUFFS_CONFIG__MODULE__DEFLATE
+#define WUFFS_CONFIG__MODULE__GIF
+#define WUFFS_CONFIG__MODULE__LZW
+#define WUFFS_CONFIG__MODULE__PNG
+#define WUFFS_CONFIG__MODULE__ZLIB
+#include "wuffs-mirror-release-c/release/c/wuffs-v0.3.c"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+#define FASTIV_IO_ERROR  fastiv_io_error_quark()
+
+G_DEFINE_QUARK(fastiv-io-error-quark, fastiv_io_error)
+
+enum FastivIoError {
+	FASTIV_IO_ERROR_OPEN,
+};
+
+static void
+set_error(GError **error, const char *message)
+{
+	g_set_error_literal(error,
+		FASTIV_IO_ERROR, FASTIV_IO_ERROR_OPEN, message);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// https://github.com/google/wuffs/blob/main/example/gifplayer/gifplayer.c
+// is pure C, and a good reference. I can't use the auxiliary libraries,
+// since they depend on C++, which is undesirable.
+static cairo_surface_t *
+open_wuffs(wuffs_base__image_decoder *dec,
+	wuffs_base__io_buffer src, GError **error)
+{
+	wuffs_base__image_config cfg;
+	wuffs_base__status status =
+		wuffs_base__image_decoder__decode_image_config(dec, &cfg, &src);
+	if (!wuffs_base__status__is_ok(&status)) {
+		set_error(error, wuffs_base__status__message(&status));
+		return NULL;
+	}
+	if (!wuffs_base__image_config__is_valid(&cfg)) {
+		set_error(error, "invalid Wuffs image configuration");
+		return NULL;
+	}
+
+	// We need to check because of the Cairo API.
+	uint32_t width = wuffs_base__pixel_config__width(&cfg.pixcfg);
+	uint32_t height = wuffs_base__pixel_config__height(&cfg.pixcfg);
+	if (width > INT_MAX || height > INT_MAX) {
+		set_error(error, "image dimensions overflow");
+		return NULL;
+	}
+
+	// CAIRO_FORMAT_ARGB32: "The 32-bit quantities are stored native-endian.
+	//   Pre-multiplied alpha is used."
+	// CAIRO_FORMAT_RGB{24,30}: analogous, not going to use these so far.
+	//
+	// Wuffs: /doc/note/pixel-formats.md specifies it as "memory order", which,
+	// for our purposes, means big endian.  Currently useful formats, as per
+	// support within wuffs_base__pixel_swizzler__prepare__*():
+	//  - WUFFS_BASE__PIXEL_FORMAT__ARGB_PREMUL: big-endian
+	//  - WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL: little-endian
+	//  - WUFFS_BASE__PIXEL_FORMAT__XRGB: big-endian
+	//  - WUFFS_BASE__PIXEL_FORMAT__BGRX: little-endian
+	//
+	// TODO(p): Make Wuffs support RGB30 as a destination format,
+	// so far we only have WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL_4X16LE
+	// and in general, 16-bit depth swizzlers are stubbed.
+	wuffs_base__pixel_config__set(&cfg.pixcfg,
+#if G_BYTE_ORDER == G_LITTLE_ENDIAN
+		WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL,
+#else
+		WUFFS_BASE__PIXEL_FORMAT__ARGB_PREMUL,
+#endif
+		WUFFS_BASE__PIXEL_SUBSAMPLING__NONE, width, height);
+
+	wuffs_base__slice_u8 workbuf = {0};
+	uint64_t workbuf_len_max_incl =
+		wuffs_base__image_decoder__workbuf_len(dec).max_incl;
+	if (workbuf_len_max_incl) {
+		workbuf = wuffs_base__malloc_slice_u8(malloc, workbuf_len_max_incl);
+		if (!workbuf.ptr) {
+			set_error(error, "failed to allocate a work buffer");
+			return NULL;
+		}
+	}
+
+	cairo_surface_t *surface =
+		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
+	cairo_status_t surface_status = cairo_surface_status(surface);
+	if (surface_status != CAIRO_STATUS_SUCCESS) {
+		set_error(error, cairo_status_to_string(surface_status));
+		cairo_surface_destroy(surface);
+		free(workbuf.ptr);
+		return NULL;
+	}
+
+	// CAIRO_STRIDE_ALIGNMENT is 4 bytes, so there will be no padding with
+	// ARGB/BGR/XRGB/BGRX.  This function does not support a stride different
+	// from the width, maybe Wuffs internals do not either.
+	wuffs_base__pixel_buffer pb = {0};
+	status = wuffs_base__pixel_buffer__set_from_slice(&pb, &cfg.pixcfg,
+		wuffs_base__make_slice_u8(cairo_image_surface_get_data(surface),
+			cairo_image_surface_get_stride(surface) *
+			cairo_image_surface_get_height(surface)));
+	if (!wuffs_base__status__is_ok(&status)) {
+		set_error(error, wuffs_base__status__message(&status));
+		cairo_surface_destroy(surface);
+		free(workbuf.ptr);
+		return NULL;
+	}
+
+#if 0  // We're not using this right now.
+	wuffs_base__frame_config fc = {0};
+	status = wuffs_png__decoder__decode_frame_config(&dec, &fc, &src);
+	if (!wuffs_base__status__is_ok(&status)) {
+		set_error(error, wuffs_base__status__message(&status));
+		cairo_surface_destroy(surface);
+		free(workbuf.ptr);
+		return NULL;
+	}
+#endif
+
+	// Starting to modify pixel data directly. Probably an unnecessary call.
+	cairo_surface_flush(surface);
+
+	status = wuffs_base__image_decoder__decode_frame(dec, &pb, &src,
+		WUFFS_BASE__PIXEL_BLEND__SRC, workbuf, NULL);
+	if (!wuffs_base__status__is_ok(&status)) {
+		set_error(error, wuffs_base__status__message(&status));
+		cairo_surface_destroy(surface);
+		free(workbuf.ptr);
+		return NULL;
+	}
+
+	// Pixel data has been written, need to let Cairo know.
+	cairo_surface_mark_dirty(surface);
+
+	free(workbuf.ptr);
+	return surface;
+}
+
+static cairo_surface_t *
+open_wuffs_using(wuffs_base__image_decoder *(*allocate)(),
+	const gchar *data, gsize len, GError **error)
+{
+	wuffs_base__image_decoder *dec = allocate();
+	if (!dec) {
+		set_error(error, "memory allocation failed or internal error");
+		return NULL;
+	}
+
+	cairo_surface_t *surface = open_wuffs(dec,
+		wuffs_base__ptr_u8__reader((uint8_t *) data, len, TRUE), error);
+	free(dec);
+	return surface;
+}
+
+static void
+trivial_cmyk_to_bgra(unsigned char *p, int len)
+{
+	// Inspired by gdk-pixbuf's io-jpeg.c:
+	//
+	// Assume that all YCCK/CMYK JPEG files use inverted CMYK, as Photoshop
+	// does, see https://bugzilla.gnome.org/show_bug.cgi?id=618096
+	while (len--) {
+		int c = p[0], m = p[1], y = p[2], k = p[3];
+		p[0] = k * y / 255;
+		p[1] = k * m / 255;
+		p[2] = k * c / 255;
+		p[3] = 255;
+		p += 4;
+	}
+}
+
+static cairo_surface_t *
+open_libjpeg_turbo(const gchar *data, gsize len, GError **error)
+{
+	tjhandle dec = tjInitDecompress();
+	if (!dec) {
+		set_error(error, tjGetErrorStr2(dec));
+		return NULL;
+	}
+
+	int width = 0, height = 0, subsampling = TJSAMP_444, colorspace = TJCS_RGB;
+	if (tjDecompressHeader3(dec, (const unsigned char *) data, len,
+			&width, &height, &subsampling, &colorspace)) {
+		set_error(error, tjGetErrorStr2(dec));
+		tjDestroy(dec);
+		return NULL;
+	}
+
+	int pixel_format = (colorspace == TJCS_CMYK || colorspace == TJCS_YCCK)
+		? TJPF_CMYK
+		: (G_BYTE_ORDER == G_LITTLE_ENDIAN ? TJPF_BGRA : TJPF_ARGB);
+
+	cairo_surface_t *surface =
+		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
+	cairo_status_t surface_status = cairo_surface_status(surface);
+	if (surface_status != CAIRO_STATUS_SUCCESS) {
+		set_error(error, cairo_status_to_string(surface_status));
+		cairo_surface_destroy(surface);
+		tjDestroy(dec);
+		return NULL;
+	}
+
+	// Starting to modify pixel data directly. Probably an unnecessary call.
+	cairo_surface_flush(surface);
+
+	int stride = cairo_image_surface_get_stride(surface);
+	if (tjDecompress2(dec, (const unsigned char *) data, len,
+			cairo_image_surface_get_data(surface), width, stride,
+			height, pixel_format, TJFLAG_ACCURATEDCT)) {
+		set_error(error, tjGetErrorStr2(dec));
+		cairo_surface_destroy(surface);
+		tjDestroy(dec);
+		return NULL;
+	}
+
+	// TODO(p): Support big-endian machines, too, those need ARGB ordering.
+	if (pixel_format == TJPF_CMYK) {
+		// CAIRO_STRIDE_ALIGNMENT is 4 bytes, so there will be no padding with
+		// ARGB/BGR/XRGB/BGRX.
+		trivial_cmyk_to_bgra(cairo_image_surface_get_data(surface),
+			width * height);
+	}
+
+	// Pixel data has been written, need to let Cairo know.
+	cairo_surface_mark_dirty(surface);
+
+	tjDestroy(dec);
+	return surface;
+}
+
+#ifdef HAVE_LIBRAW  // ---------------------------------------------------------
+
+static cairo_surface_t *
+open_libraw(const gchar *data, gsize len, GError **error)
+{
+	// https://github.com/LibRaw/LibRaw/issues/418
+	libraw_data_t *iprc = libraw_init(LIBRAW_OPIONS_NO_MEMERR_CALLBACK
+		| LIBRAW_OPIONS_NO_DATAERR_CALLBACK);
+	if (!iprc) {
+		set_error(error, "failed to obtain a LibRaw handle");
+		return NULL;
+	}
+
+#if 0
+	// TODO(p): Consider setting this--the image is still likely to be
+	// rendered suboptimally, so why not make it faster.
+	iprc->params.half_size = 1;
+#endif
+
+	// TODO(p): Check if we need to set anything for autorotation (sizes.flip).
+	iprc->params.use_camera_wb = 1;
+	iprc->params.output_color = 1;  // sRGB, TODO(p): Is this used?
+	iprc->params.output_bps = 8;  // This should be the default value.
+
+	int err = 0;
+	if ((err = libraw_open_buffer(iprc, (void *) data, len))) {
+		set_error(error, libraw_strerror(err));
+		libraw_close(iprc);
+		return NULL;
+	}
+
+	// TODO(p): Do we need to check iprc->idata.raw_count? Maybe for TIFFs?
+	if ((err = libraw_unpack(iprc))) {
+		set_error(error, libraw_strerror(err));
+		libraw_close(iprc);
+		return NULL;
+	}
+
+#if 0
+	// TODO(p): I'm not sure when this is necessary or useful yet.
+	if ((err = libraw_adjust_sizes_info_only(iprc))) {
+		set_error(error, libraw_strerror(err));
+		libraw_close(iprc);
+		return NULL;
+	}
+#endif
+
+	// TODO(p): Documentation says I should look at the code and do it myself.
+	if ((err = libraw_dcraw_process(iprc))) {
+		set_error(error, libraw_strerror(err));
+		libraw_close(iprc);
+		return NULL;
+	}
+
+	// FIXME: This is shittily written to iterate over the range of
+	// idata.colors, and will be naturally slow.
+	libraw_processed_image_t *image = libraw_dcraw_make_mem_image(iprc, &err);
+	if (!image) {
+		set_error(error, libraw_strerror(err));
+		libraw_close(iprc);
+		return NULL;
+	}
+
+	// This should have been transformed, and kept, respectively.
+	if (image->colors != 3 || image->bits != 8) {
+		set_error(error, "unexpected number of colours, or bit depth");
+		libraw_dcraw_clear_mem(image);
+		libraw_close(iprc);
+		return NULL;
+	}
+
+	int width = image->width, height = image->height;
+	cairo_surface_t *surface =
+		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
+	cairo_status_t surface_status = cairo_surface_status(surface);
+	if (surface_status != CAIRO_STATUS_SUCCESS) {
+		set_error(error, cairo_status_to_string(surface_status));
+		cairo_surface_destroy(surface);
+		libraw_dcraw_clear_mem(image);
+		libraw_close(iprc);
+		return NULL;
+	}
+
+	// Starting to modify pixel data directly. Probably an unnecessary call.
+	cairo_surface_flush(surface);
+
+	uint32_t *pixels = (uint32_t *) cairo_image_surface_get_data(surface);
+	unsigned char *p = image->data;
+	for (ushort y = 0; y < image->height; y++) {
+		for (ushort x = 0; x < image->width; x++) {
+			*pixels++ = 0xff000000 | (uint32_t) p[0] << 16
+				| (uint32_t) p[1] << 8 | (uint32_t) p[2];
+			p += 3;
+		}
+	}
+
+	// Pixel data has been written, need to let Cairo know.
+	cairo_surface_mark_dirty(surface);
+
+	libraw_dcraw_clear_mem(image);
+	libraw_close(iprc);
+	return surface;
+}
+
+#endif  // HAVE_LIBRAW ---------------------------------------------------------
+
+cairo_surface_t *
+fastiv_io_open(const gchar *path, GError **error)
+{
+	// TODO(p): Don't always load everything into memory, test type first,
+	// for which we only need the first 16 bytes right now.
+	// Though LibRaw poses an issue--we may want to try to map RAW formats
+	// to FourCC values--many of them are compliant TIFF files.
+	// We might want to employ a more generic way of magic identification,
+	// and with some luck, it could even be integrated into Wuffs.
+	gchar *data = NULL;
+	gsize len = 0;
+	if (!g_file_get_contents(path, &data, &len, error))
+		return NULL;
+
+	wuffs_base__slice_u8 prefix =
+		wuffs_base__make_slice_u8((uint8_t *) data, len);
+
+	cairo_surface_t *surface = NULL;
+	switch (wuffs_base__magic_number_guess_fourcc(prefix)) {
+	case WUFFS_BASE__FOURCC__BMP:
+		// Note that BMP can redirect into another format, which is unsupported.
+		surface = open_wuffs_using(
+			wuffs_bmp__decoder__alloc_as__wuffs_base__image_decoder,
+			data, len, error);
+		break;
+	case WUFFS_BASE__FOURCC__GIF:
+		surface = open_wuffs_using(
+			wuffs_gif__decoder__alloc_as__wuffs_base__image_decoder,
+			data, len, error);
+		break;
+	case WUFFS_BASE__FOURCC__PNG:
+		surface = open_wuffs_using(
+			wuffs_png__decoder__alloc_as__wuffs_base__image_decoder,
+			data, len, error);
+		break;
+	case WUFFS_BASE__FOURCC__JPEG:
+		surface = open_libjpeg_turbo(data, len, error);
+		break;
+	default:
+#ifdef HAVE_LIBRAW  // ---------------------------------------------------------
+		if ((surface = open_libraw(data, len, error)))
+			break;
+
+		// TODO(p): We should try to pass actual processing errors through,
+		// notably only continue with LIBRAW_FILE_UNSUPPORTED.
+		g_clear_error(error);
+#endif  // HAVE_LIBRAW ---------------------------------------------------------
+
+		// TODO(p): Integrate gdk-pixbuf as a fallback (optional dependency).
+		set_error(error, "unsupported file type");
+	}
+	free(data);
+	return surface;
+}

fastiv-view.c

@@ -15,37 +15,37 @@
 // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 //
 
-#define WUFFS_IMPLEMENTATION
-#define WUFFS_CONFIG__MODULES
-#define WUFFS_CONFIG__MODULE__ADLER32
-#define WUFFS_CONFIG__MODULE__BASE
-#define WUFFS_CONFIG__MODULE__BMP
-#define WUFFS_CONFIG__MODULE__CRC32
-#define WUFFS_CONFIG__MODULE__DEFLATE
-#define WUFFS_CONFIG__MODULE__GIF
-#define WUFFS_CONFIG__MODULE__LZW
-#define WUFFS_CONFIG__MODULE__PNG
-#define WUFFS_CONFIG__MODULE__ZLIB
+#include <math.h>
 
-#include "wuffs-mirror-release-c/release/c/wuffs-v0.3.c"
-#include <turbojpeg.h>
-
-#include "config.h"
 #include "fastiv-view.h"
 
-#ifdef HAVE_LIBRAW
-#include <libraw.h>
-#endif  // HAVE_LIBRAW
-
 struct _FastivView {
 	GtkWidget parent_instance;
 	cairo_surface_t *surface;
-	// TODO(p): Eventually, we'll want to have the zoom level (scale) here,
-	// and some zoom-to-fit indication.
+	// TODO(p): Zoom-to-fit indication.
+	double scale;
 };
 
 G_DEFINE_TYPE(FastivView, fastiv_view, GTK_TYPE_WIDGET)
 
+static int
+get_display_width(FastivView *self)
+{
+	if (!self->surface)
+		return 0;
+
+	return ceil(cairo_image_surface_get_width(self->surface) * self->scale);
+}
+
+static int
+get_display_height(FastivView *self)
+{
+	if (!self->surface)
+		return 0;
+
+	return ceil(cairo_image_surface_get_height(self->surface) * self->scale);
+}
+
 static void
 fastiv_view_finalize(GObject *gobject)
 {
@@ -62,10 +62,8 @@ fastiv_view_get_preferred_height(GtkWidget *widget,
 	*minimum = 0;
 	*natural = 0;
 
-	// TODO(p): Times the zoom.
 	FastivView *self = FASTIV_VIEW(widget);
-	if (self->surface)
-		*natural = cairo_image_surface_get_height(self->surface);
+	*natural = get_display_height(self);
 }
 
 static void
@@ -75,10 +73,8 @@ fastiv_view_get_preferred_width(GtkWidget *widget,
 	*minimum = 0;
 	*natural = 0;
 
-	// TODO(p): Times the zoom.
 	FastivView *self = FASTIV_VIEW(widget);
-	if (self->surface)
-		*natural = cairo_image_surface_get_width(self->surface);
+	*natural = get_display_width(self);
 }
 
 static gboolean
@@ -95,8 +91,8 @@ fastiv_view_draw(GtkWidget *widget, cairo_t *cr)
 	GtkAllocation allocation;
 	gtk_widget_get_allocation(widget, &allocation);
 
-	int w = cairo_image_surface_get_width(self->surface);
-	int h = cairo_image_surface_get_height(self->surface);
+	int w = get_display_width(self);
+	int h = get_display_height(self);
 
 	double x = 0;
 	double y = 0;
@@ -105,8 +101,10 @@ fastiv_view_draw(GtkWidget *widget, cairo_t *cr)
 	if (h < allocation.height)
 		y = (allocation.height - h) / 2;
 
-	// TODO(p): Times the zoom.
-	cairo_set_source_surface(cr, self->surface, x, y);
+	cairo_scale(cr, self->scale, self->scale);
+	cairo_set_source_surface(cr, self->surface,
+		x / self->scale, y / self->scale);
+
 	cairo_paint(cr);
 	return TRUE;
 }
@@ -126,393 +124,20 @@ fastiv_view_class_init(FastivViewClass *klass)
 static void
 fastiv_view_init(FastivView *self)
 {
+	self->scale = 1.0;
+
 	gtk_widget_set_has_window(GTK_WIDGET(self), FALSE);
 }
 
 // --- Picture loading ---------------------------------------------------------
 
-#define FASTIV_VIEW_ERROR  fastiv_view_error_quark()
-
-G_DEFINE_QUARK(fastiv-view-error-quark, fastiv_view_error)
-
-enum FastivViewError {
-	FASTIV_VIEW_ERROR_OPEN,
-};
-
-static void
-set_error(GError **error, const char *message)
-{
-	g_set_error_literal(error,
-		FASTIV_VIEW_ERROR, FASTIV_VIEW_ERROR_OPEN, message);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-// https://github.com/google/wuffs/blob/main/example/gifplayer/gifplayer.c
-// is pure C, and a good reference. I can't use the auxiliary libraries,
-// since they depend on C++, which is undesirable.
-static cairo_surface_t *
-open_wuffs(wuffs_base__image_decoder *dec,
-	wuffs_base__io_buffer src, GError **error)
-{
-	wuffs_base__image_config cfg;
-	wuffs_base__status status =
-		wuffs_base__image_decoder__decode_image_config(dec, &cfg, &src);
-	if (!wuffs_base__status__is_ok(&status)) {
-		set_error(error, wuffs_base__status__message(&status));
-		return NULL;
-	}
-	if (!wuffs_base__image_config__is_valid(&cfg)) {
-		set_error(error, "invalid Wuffs image configuration");
-		return NULL;
-	}
-
-	// We need to check because of the Cairo API.
-	uint32_t width = wuffs_base__pixel_config__width(&cfg.pixcfg);
-    uint32_t height = wuffs_base__pixel_config__height(&cfg.pixcfg);
-	if (width > INT_MAX || height > INT_MAX) {
-		set_error(error, "image dimensions overflow");
-		return NULL;
-	}
-
-	// CAIRO_FORMAT_ARGB32: "The 32-bit quantities are stored native-endian.
-	//   Pre-multiplied alpha is used."
-	// CAIRO_FORMAT_RGB{24,30}: analogous, not going to use these so far.
-	//
-	// Wuffs: /doc/note/pixel-formats.md specifies it as "memory order", which,
-	// for our purposes, means big endian.  Currently useful formats, as per
-	// support within wuffs_base__pixel_swizzler__prepare__*():
-	//  - WUFFS_BASE__PIXEL_FORMAT__ARGB_PREMUL: big-endian
-	//  - WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL: little-endian
-	//  - WUFFS_BASE__PIXEL_FORMAT__XRGB: big-endian
-	//  - WUFFS_BASE__PIXEL_FORMAT__BGRX: little-endian
-	//
-	// TODO(p): Make Wuffs support RGB30 as a destination format,
-	// so far we only have WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL_4X16LE
-	// and in general, 16-bit depth swizzlers are stubbed.
-	wuffs_base__pixel_config__set(&cfg.pixcfg,
-#if G_BYTE_ORDER == G_LITTLE_ENDIAN
-		WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL,
-#else
-		WUFFS_BASE__PIXEL_FORMAT__ARGB_PREMUL,
-#endif
-		WUFFS_BASE__PIXEL_SUBSAMPLING__NONE, width, height);
-
-	wuffs_base__slice_u8 workbuf = {0};
-	uint64_t workbuf_len_max_incl =
-		wuffs_base__image_decoder__workbuf_len(dec).max_incl;
-	if (workbuf_len_max_incl) {
-		workbuf = wuffs_base__malloc_slice_u8(malloc, workbuf_len_max_incl);
-		if (!workbuf.ptr) {
-			set_error(error, "failed to allocate a work buffer");
-			return NULL;
-		}
-	}
-
-	cairo_surface_t *surface =
-		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
-	if (!surface) {
-		set_error(error, "failed to allocate an image surface");
-		free(workbuf.ptr);
-		return NULL;
-	}
-
-	// CAIRO_STRIDE_ALIGNMENT is 4 bytes, so there will be no padding with
-	// ARGB/BGR/XRGB/BGRX.  This function does not support a stride different
-	// from the width, maybe Wuffs internals do not either.
-	wuffs_base__pixel_buffer pb = {0};
-	status = wuffs_base__pixel_buffer__set_from_slice(&pb, &cfg.pixcfg,
-		wuffs_base__make_slice_u8(cairo_image_surface_get_data(surface),
-			cairo_image_surface_get_stride(surface) *
-			cairo_image_surface_get_height(surface)));
-	if (!wuffs_base__status__is_ok(&status)) {
-		set_error(error, wuffs_base__status__message(&status));
-		cairo_surface_destroy(surface);
-		free(workbuf.ptr);
-		return NULL;
-	}
-
-#if 0  // We're not using this right now.
-	wuffs_base__frame_config fc = {0};
-	status = wuffs_png__decoder__decode_frame_config(&dec, &fc, &src);
-	if (!wuffs_base__status__is_ok(&status)) {
-		set_error(error, wuffs_base__status__message(&status));
-		cairo_surface_destroy(surface);
-		free(workbuf.ptr);
-		return NULL;
-	}
-#endif
-
-	// Starting to modify pixel data directly. Probably an unnecessary call.
-	cairo_surface_flush(surface);
-
-	status = wuffs_base__image_decoder__decode_frame(dec, &pb, &src,
-		WUFFS_BASE__PIXEL_BLEND__SRC, workbuf, NULL);
-	if (!wuffs_base__status__is_ok(&status)) {
-		set_error(error, wuffs_base__status__message(&status));
-		cairo_surface_destroy(surface);
-		free(workbuf.ptr);
-		return NULL;
-	}
-
-	// Pixel data has been written, need to let Cairo know.
-	cairo_surface_mark_dirty(surface);
-
-	free(workbuf.ptr);
-	return surface;
-}
-
-static cairo_surface_t *
-open_wuffs_using(wuffs_base__image_decoder *(*allocate)(),
-	const gchar *data, gsize len, GError **error)
-{
-	wuffs_base__image_decoder *dec = allocate();
-	if (!dec) {
-		set_error(error, "memory allocation failed or internal error");
-		return NULL;
-	}
-
-	cairo_surface_t *surface = open_wuffs(dec,
-		wuffs_base__ptr_u8__reader((uint8_t *) data, len, TRUE), error);
-	free(dec);
-	return surface;
-}
-
-static void
-trivial_cmyk_to_bgra(unsigned char *p, int len)
-{
-	// Inspired by gdk-pixbuf's io-jpeg.c:
-	//
-	// Assume that all YCCK/CMYK JPEG files use inverted CMYK, as Photoshop
-	// does, see https://bugzilla.gnome.org/show_bug.cgi?id=618096
-	while (len--) {
-		int c = p[0], m = p[1], y = p[2], k = p[3];
-		p[0] = k * y / 255;
-		p[1] = k * m / 255;
-		p[2] = k * c / 255;
-		p[3] = 255;
-		p += 4;
-	}
-}
-
-static cairo_surface_t *
-open_libjpeg_turbo(const gchar *data, gsize len, GError **error)
-{
-	tjhandle dec = tjInitDecompress();
-	if (!dec) {
-		set_error(error, tjGetErrorStr2(dec));
-		return NULL;
-	}
-
-	int width = 0, height = 0, subsampling = TJSAMP_444, colorspace = TJCS_RGB;
-	if (tjDecompressHeader3(dec, (const unsigned char *) data, len,
-			&width, &height, &subsampling, &colorspace)) {
-		set_error(error, tjGetErrorStr2(dec));
-		tjDestroy(dec);
-		return NULL;
-	}
-
-	int pixel_format = (colorspace == TJCS_CMYK || colorspace == TJCS_YCCK)
-		? TJPF_CMYK
-		: (G_BYTE_ORDER == G_LITTLE_ENDIAN ? TJPF_BGRA : TJPF_ARGB);
-
-	cairo_surface_t *surface =
-		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
-	if (!surface) {
-		set_error(error, "failed to allocate an image surface");
-		tjDestroy(dec);
-		return NULL;
-	}
-
-	// Starting to modify pixel data directly. Probably an unnecessary call.
-	cairo_surface_flush(surface);
-
-	int stride = cairo_image_surface_get_stride(surface);
-	if (tjDecompress2(dec, (const unsigned char *) data, len,
-			cairo_image_surface_get_data(surface), width, stride,
-			height, pixel_format, TJFLAG_ACCURATEDCT)) {
-		set_error(error, tjGetErrorStr2(dec));
-		cairo_surface_destroy(surface);
-		tjDestroy(dec);
-		return NULL;
-	}
-
-	// TODO(p): Support big-endian machines, too, those need ARGB ordering.
-	if (pixel_format == TJPF_CMYK) {
-		// CAIRO_STRIDE_ALIGNMENT is 4 bytes, so there will be no padding with
-		// ARGB/BGR/XRGB/BGRX.
-		trivial_cmyk_to_bgra(cairo_image_surface_get_data(surface),
-			width * height);
-	}
-
-	// Pixel data has been written, need to let Cairo know.
-	cairo_surface_mark_dirty(surface);
-
-	tjDestroy(dec);
-	return surface;
-}
-
-#ifdef HAVE_LIBRAW  // ---------------------------------------------------------
-
-static cairo_surface_t *
-open_libraw(const gchar *data, gsize len, GError **error)
-{
-	// https://github.com/LibRaw/LibRaw/issues/418
-	libraw_data_t *iprc = libraw_init(LIBRAW_OPIONS_NO_MEMERR_CALLBACK
-		| LIBRAW_OPIONS_NO_DATAERR_CALLBACK);
-	if (!iprc) {
-		set_error(error, "failed to obtain a LibRaw handle");
-		return NULL;
-	}
-
-#if 0
-	// TODO(p): Consider setting this--the image is still likely to be
-	// rendered suboptimally, so why not make it faster.
-	iprc->params.half_size = 1;
-#endif
-
-	// TODO(p): Check if we need to set anything for autorotation (sizes.flip).
-	iprc->params.use_camera_wb = 1;
-	iprc->params.output_color = 1;  // sRGB, TODO(p): Is this used?
-	iprc->params.output_bps = 8;  // This should be the default value.
-
-	int err = 0;
-	if ((err = libraw_open_buffer(iprc, (void *) data, len))) {
-		set_error(error, libraw_strerror(err));
-		libraw_close(iprc);
-		return NULL;
-	}
-
-	// TODO(p): Do we need to check iprc->idata.raw_count? Maybe for TIFFs?
-	if ((err = libraw_unpack(iprc))) {
-		set_error(error, libraw_strerror(err));
-		libraw_close(iprc);
-		return NULL;
-	}
-
-#if 0
-	// TODO(p): I'm not sure when this is necessary or useful yet.
-	if ((err = libraw_adjust_sizes_info_only(iprc))) {
-		set_error(error, libraw_strerror(err));
-		libraw_close(iprc);
-		return NULL;
-	}
-#endif
-
-	// TODO(p): Documentation says I should look at the code and do it myself.
-	if ((err = libraw_dcraw_process(iprc))) {
-		set_error(error, libraw_strerror(err));
-		libraw_close(iprc);
-		return NULL;
-	}
-
-	// FIXME: This is shittily written to iterate over the range of
-	// idata.colors, and will be naturally slow.
-	libraw_processed_image_t *image = libraw_dcraw_make_mem_image(iprc, &err);
-	if (!image) {
-		set_error(error, libraw_strerror(err));
-		libraw_close(iprc);
-		return NULL;
-	}
-
-	// This should have been transformed, and kept, respectively.
-	if (image->colors != 3 || image->bits != 8) {
-		set_error(error, "unexpected number of colours, or bit depth");
-		libraw_dcraw_clear_mem(image);
-		libraw_close(iprc);
-		return NULL;
-	}
-
-	int width = image->width, height = image->height;
-	cairo_surface_t *surface =
-		cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
-	if (!surface) {
-		set_error(error, "failed to allocate an image surface");
-		libraw_dcraw_clear_mem(image);
-		libraw_close(iprc);
-		return NULL;
-	}
-
-	// Starting to modify pixel data directly. Probably an unnecessary call.
-	cairo_surface_flush(surface);
-
-	uint32_t *pixels = (uint32_t *) cairo_image_surface_get_data(surface);
-	unsigned char *p = image->data;
-	for (ushort y = 0; y < image->height; y++) {
-		for (ushort x = 0; x < image->width; x++) {
-			*pixels++ = 0xff000000 | (uint32_t) p[0] << 16
-				| (uint32_t) p[1] << 8 | (uint32_t) p[2];
-			p += 3;
-		}
-	}
-
-	// Pixel data has been written, need to let Cairo know.
-	cairo_surface_mark_dirty(surface);
-
-	libraw_dcraw_clear_mem(image);
-	libraw_close(iprc);
-	return surface;
-}
-
-#endif  // HAVE_LIBRAW ---------------------------------------------------------
-
 // TODO(p): Progressive picture loading, or at least async/cancellable.
 gboolean
 fastiv_view_open(FastivView *self, const gchar *path, GError **error)
 {
-	// TODO(p): Don't always load everything into memory, test type first,
-	// for which we only need the first 16 bytes right now.
-	// Though LibRaw poses an issue--we may want to try to map RAW formats
-	// to FourCC values--many of them are compliant TIFF files.
-	// We might want to employ a more generic way of magic identification,
-	// and with some luck, it could even be integrated into Wuffs.
-	gchar *data = NULL;
-	gsize len = 0;
-	if (!g_file_get_contents(path, &data, &len, error))
-		return FALSE;
-
-	wuffs_base__slice_u8 prefix =
-		wuffs_base__make_slice_u8((uint8_t *) data, len);
-
-	cairo_surface_t *surface = NULL;
-	switch (wuffs_base__magic_number_guess_fourcc(prefix)) {
-	case WUFFS_BASE__FOURCC__BMP:
-		// Note that BMP can redirect into another format, which is unsupported.
-		surface = open_wuffs_using(
-			wuffs_bmp__decoder__alloc_as__wuffs_base__image_decoder,
-			data, len, error);
-		break;
-	case WUFFS_BASE__FOURCC__GIF:
-		surface = open_wuffs_using(
-			wuffs_gif__decoder__alloc_as__wuffs_base__image_decoder,
-			data, len, error);
-		break;
-	case WUFFS_BASE__FOURCC__PNG:
-		surface = open_wuffs_using(
-			wuffs_png__decoder__alloc_as__wuffs_base__image_decoder,
-			data, len, error);
-		break;
-	case WUFFS_BASE__FOURCC__JPEG:
-		surface = open_libjpeg_turbo(data, len, error);
-		break;
-	default:
-#ifdef HAVE_LIBRAW  // ---------------------------------------------------------
-		if ((surface = open_libraw(data, len, error)))
-			break;
-
-		// TODO(p): We should try to pass actual processing errors through,
-		// notably only continue with LIBRAW_FILE_UNSUPPORTED.
-		g_clear_error(error);
-#endif  // HAVE_LIBRAW ---------------------------------------------------------
-
-		// TODO(p): Integrate gdk-pixbuf as a fallback (optional dependency).
-		set_error(error, "unsupported file type");
-	}
-
-	free(data);
+	cairo_surface_t *surface = fastiv_io_open(path, error);
 	if (!surface)
 		return FALSE;
-
 	if (self->surface)
 		cairo_surface_destroy(self->surface);
 

fastiv-view.h

@@ -24,3 +24,6 @@ G_DECLARE_FINAL_TYPE(FastivView, fastiv_view, FASTIV, VIEW, GtkWidget)
 
 /// Try to open the given file, synchronously, to be displayed by the widget.
 gboolean fastiv_view_open(FastivView *self, const gchar *path, GError **error);
+
+// Private, fastiv-io.c
+cairo_surface_t *fastiv_io_open(const gchar *path, GError **error);

meson.build

@@ -6,6 +6,7 @@ dependencies = [
 	dependency('gtk+-3.0'),
 	dependency('libturbojpeg'),
 	libraw,
+	meson.get_compiler('c').find_library('m', required : false),
 ]
 
 conf = configuration_data()
@@ -17,10 +18,18 @@ configure_file(
 	configuration : conf,
 )
 
-executable('fastiv', 'fastiv.c', 'fastiv-view.c',
+executable('fastiv', 'fastiv.c', 'fastiv-view.c', 'fastiv-io.c',
 	install : true,
 	dependencies : [dependencies])
 
+# TODO(p): See fastiv_io_open(), consider optionally integrating this.
+gdk_pixbuf = dependency('gdk-pixbuf-2.0', required : false)
+if gdk_pixbuf.found()
+	executable('io-benchmark', 'fastiv-io-benchmark.c', 'fastiv-io.c',
+		build_by_default : false,
+		dependencies : [dependencies, gdk_pixbuf])
+endif
+
 install_data('fastiv.desktop',
 	install_dir : get_option('datadir') + '/applications')
 install_data('fastiv.svg',