Stop abusing Cairo user data, part 1

This commit temporarily breaks multi-page images and animations.

fiv-io.h

@@ -33,92 +33,6 @@ void fiv_io_profile_free(FivIoProfile self);
 // From libwebp, verified to exactly match [x * a / 255].
 #define PREMULTIPLY8(a, x) (((uint32_t) (x) * (uint32_t) (a) * 32897U) >> 23)
 
-// --- Loading -----------------------------------------------------------------
-
-extern const char *fiv_io_supported_media_types[];
-
-gchar **fiv_io_all_supported_media_types(void);
-
-// Userdata are typically attached to all Cairo surfaces in an animation.
-
-/// GBytes with plain Exif/TIFF data.
-extern cairo_user_data_key_t fiv_io_key_exif;
-/// FivIoOrientation, as a uintptr_t.
-extern cairo_user_data_key_t fiv_io_key_orientation;
-/// GBytes with plain ICC profile data.
-extern cairo_user_data_key_t fiv_io_key_icc;
-/// GBytes with plain XMP data.
-extern cairo_user_data_key_t fiv_io_key_xmp;
-/// GBytes with a WebP's THUM chunk, used for our thumbnails.
-extern cairo_user_data_key_t fiv_io_key_thum;
-/// GHashTable with key-value pairs from PNG's tEXt, zTXt, iTXt chunks.
-/// Currently only read by fiv_io_open_png_thumbnail().
-extern cairo_user_data_key_t fiv_io_key_text;
-
-/// The next frame in a sequence, as a surface, in a chain, pre-composited.
-/// There is no wrap-around.
-extern cairo_user_data_key_t fiv_io_key_frame_next;
-/// The previous frame in a sequence, as a surface, in a chain, pre-composited.
-/// This is a weak pointer that wraps around, and needn't be present
-/// for static images.
-extern cairo_user_data_key_t fiv_io_key_frame_previous;
-/// Frame duration in milliseconds as an intptr_t.
-extern cairo_user_data_key_t fiv_io_key_frame_duration;
-/// How many times to repeat the animation, or zero for +inf, as a uintptr_t.
-extern cairo_user_data_key_t fiv_io_key_loops;
-
-/// The first frame of the next page, as a surface, in a chain.
-/// There is no wrap-around.
-extern cairo_user_data_key_t fiv_io_key_page_next;
-/// The first frame of the previous page, as a surface, in a chain.
-/// There is no wrap-around. This is a weak pointer.
-extern cairo_user_data_key_t fiv_io_key_page_previous;
-
-typedef struct _FivIoRenderClosure {
-	/// The rendering is allowed to fail, returning NULL.
-	cairo_surface_t *(*render)(struct _FivIoRenderClosure *, double scale);
-} FivIoRenderClosure;
-
-/// A FivIoRenderClosure for parametrized re-rendering of vector formats.
-/// This is attached at the page level.
-/// The rendered image will not have this key.
-extern cairo_user_data_key_t fiv_io_key_render;
-
-typedef struct {
-	const char *uri;                    ///< Source URI
-	FivIoProfile screen_profile;        ///< Target colour space or NULL
-	int screen_dpi;                     ///< Target DPI
-	gboolean enhance;                   ///< Enhance JPEG (currently)
-	gboolean first_frame_only;          ///< Only interested in the 1st frame
-	GPtrArray *warnings;                ///< String vector for non-fatal errors
-} FivIoOpenContext;
-
-cairo_surface_t *fiv_io_open(const FivIoOpenContext *ctx, GError **error);
-cairo_surface_t *fiv_io_open_from_data(
-	const char *data, size_t len, const FivIoOpenContext *ctx, GError **error);
-cairo_surface_t *fiv_io_open_png_thumbnail(const char *path, GError **error);
-
-// --- Thumbnail passing utilities ---------------------------------------------
-
-enum { FIV_IO_SERIALIZE_LOW_QUALITY = 1 << 0 };
-
-void fiv_io_serialize_to_stdout(cairo_surface_t *surface, guint64 user_data);
-cairo_surface_t *fiv_io_deserialize(GBytes *bytes, guint64 *user_data);
-
-GBytes *fiv_io_serialize_for_search(cairo_surface_t *surface, GError **error);
-
-// --- Export ------------------------------------------------------------------
-
-/// Encodes a Cairo surface as a WebP bitstream, following the configuration.
-/// The result needs to be freed using WebPFree/WebPDataClear().
-unsigned char *fiv_io_encode_webp(
-	cairo_surface_t *surface, const WebPConfig *config, size_t *len);
-
-/// Saves the page as a lossless WebP still picture or animation.
-/// If no exact frame is specified, this potentially creates an animation.
-gboolean fiv_io_save(cairo_surface_t *page, cairo_surface_t *frame,
-	FivIoProfile target, const char *path, GError **error);
-
 // --- Metadata ----------------------------------------------------------------
 
 // https://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf Table 6
@@ -147,3 +61,143 @@ FivIoOrientation fiv_io_exif_orientation(const guint8 *exif, gsize len);
 /// Save metadata attached by this module in Exiv2 format.
 gboolean fiv_io_save_metadata(
 	cairo_surface_t *page, const char *path, GError **error);
+
+// --- Loading -----------------------------------------------------------------
+
+extern const char *fiv_io_supported_media_types[];
+
+gchar **fiv_io_all_supported_media_types(void);
+
+typedef struct _FivIoRenderClosure {
+	/// The rendering is allowed to fail, returning NULL.
+	cairo_surface_t *(*render)(struct _FivIoRenderClosure *, double scale);
+	void (*destroy)(struct _FivIoRenderClosure *);
+} FivIoRenderClosure;
+
+typedef struct _FivIoImage {
+	uint8_t *data;                      ///< Raw image data
+	cairo_format_t format;              ///< Data format
+	uint32_t width;                     ///< Width of the image in pixels
+	uint32_t stride;                    ///< Row stride in bytes
+	uint32_t height;                    ///< Height of the image in pixels
+
+	FivIoOrientation orientation;       ///< Orientation to use for display
+
+	GBytes *exif;                       ///< Raw Exif/TIFF segment
+	GBytes *icc;                        ///< Raw ICC profile data
+	GBytes *xmp;                        ///< Raw XMP data
+	GBytes *thum;                       ///< WebP THUM chunk, for our thumbnails
+
+	/// A FivIoRenderClosure for parametrized re-rendering of vector formats.
+	/// This is attached at the page level.
+	FivIoRenderClosure *render;
+
+	/// The first frame of the next page, in a chain.
+	/// There is no wrap-around.
+	struct _FivIoImage *page_next;
+
+	/// The first frame of the previous page, in a chain.
+	/// There is no wrap-around. This is a weak pointer.
+	struct _FivIoImage *page_previous;
+
+	/// The next frame in a sequence, in a chain, pre-composited.
+	/// There is no wrap-around.
+	struct _FivIoImage *frame_next;
+
+	/// The previous frame in a sequence, in a chain, pre-composited.
+	/// This is a weak pointer that wraps around,
+	/// and needn't be present for static images.
+	struct _FivIoImage *frame_previous;
+
+	/// Frame duration in milliseconds.
+	int64_t frame_duration;
+
+	/// How many times to repeat the animation, or zero for +inf.
+	uint64_t loops;
+} FivIoImage;
+
+FivIoImage *fiv_io_image_ref(FivIoImage *image);
+void fiv_io_image_unref(FivIoImage *image);
+
+/// Return a new Cairo image surface referencing the same data as the image,
+/// eating the reference to it.
+cairo_surface_t *fiv_io_image_to_surface(FivIoImage *image);
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// Userdata are typically attached to all Cairo surfaces in an animation.
+
+/// GBytes with plain Exif/TIFF data.
+extern cairo_user_data_key_t fiv_io_key_exif;
+/// FivIoOrientation, as a uintptr_t.
+extern cairo_user_data_key_t fiv_io_key_orientation;
+/// GBytes with plain ICC profile data.
+extern cairo_user_data_key_t fiv_io_key_icc;
+/// GBytes with plain XMP data.
+extern cairo_user_data_key_t fiv_io_key_xmp;
+/// GBytes with a WebP's THUM chunk, used for our thumbnails.
+extern cairo_user_data_key_t fiv_io_key_thum;
+
+/// GHashTable with key-value pairs from PNG's tEXt, zTXt, iTXt chunks.
+/// Currently only read by fiv_io_open_png_thumbnail().
+extern cairo_user_data_key_t fiv_io_key_text;
+
+/// The next frame in a sequence, as a surface, in a chain, pre-composited.
+/// There is no wrap-around.
+extern cairo_user_data_key_t fiv_io_key_frame_next;
+/// The previous frame in a sequence, as a surface, in a chain, pre-composited.
+/// This is a weak pointer that wraps around, and needn't be present
+/// for static images.
+extern cairo_user_data_key_t fiv_io_key_frame_previous;
+/// Frame duration in milliseconds as an intptr_t.
+extern cairo_user_data_key_t fiv_io_key_frame_duration;
+/// How many times to repeat the animation, or zero for +inf, as a uintptr_t.
+extern cairo_user_data_key_t fiv_io_key_loops;
+
+/// The first frame of the next page, as a surface, in a chain.
+/// There is no wrap-around.
+extern cairo_user_data_key_t fiv_io_key_page_next;
+/// The first frame of the previous page, as a surface, in a chain.
+/// There is no wrap-around. This is a weak pointer.
+extern cairo_user_data_key_t fiv_io_key_page_previous;
+
+/// A FivIoRenderClosure for parametrized re-rendering of vector formats.
+/// This is attached at the page level.
+/// The rendered image will not have this key.
+extern cairo_user_data_key_t fiv_io_key_render;
+
+typedef struct {
+	const char *uri;                    ///< Source URI
+	FivIoProfile screen_profile;        ///< Target colour space or NULL
+	int screen_dpi;                     ///< Target DPI
+	gboolean enhance;                   ///< Enhance JPEG (currently)
+	gboolean first_frame_only;          ///< Only interested in the 1st frame
+	GPtrArray *warnings;                ///< String vector for non-fatal errors
+} FivIoOpenContext;
+
+FivIoImage *fiv_io_open(const FivIoOpenContext *ctx, GError **error);
+FivIoImage *fiv_io_open_from_data(
+	const char *data, size_t len, const FivIoOpenContext *ctx, GError **error);
+
+cairo_surface_t *fiv_io_open_png_thumbnail(const char *path, GError **error);
+
+// --- Thumbnail passing utilities ---------------------------------------------
+
+enum { FIV_IO_SERIALIZE_LOW_QUALITY = 1 << 0 };
+
+void fiv_io_serialize_to_stdout(cairo_surface_t *surface, guint64 user_data);
+cairo_surface_t *fiv_io_deserialize(GBytes *bytes, guint64 *user_data);
+
+GBytes *fiv_io_serialize_for_search(cairo_surface_t *surface, GError **error);
+
+// --- Export ------------------------------------------------------------------
+
+/// Encodes a Cairo surface as a WebP bitstream, following the configuration.
+/// The result needs to be freed using WebPFree/WebPDataClear().
+unsigned char *fiv_io_encode_webp(
+	cairo_surface_t *surface, const WebPConfig *config, size_t *len);
+
+/// Saves the page as a lossless WebP still picture or animation.
+/// If no exact frame is specified, this potentially creates an animation.
+gboolean fiv_io_save(cairo_surface_t *page, cairo_surface_t *frame,
+	FivIoProfile target, const char *path, GError **error);

fiv-thumbnail.c

@@ -137,8 +137,8 @@ render(GFile *target, GBytes *data, gboolean *color_managed, GError **error)
 		.warnings = g_ptr_array_new_with_free_func(g_free),
 	};
 
-	cairo_surface_t *surface = fiv_io_open_from_data(
+	cairo_surface_t *surface = fiv_io_image_to_surface(fiv_io_open_from_data(
-		g_bytes_get_data(data, NULL), g_bytes_get_size(data), &ctx, error);
+		g_bytes_get_data(data, NULL), g_bytes_get_size(data), &ctx, error));
 	g_free((gchar *) ctx.uri);
 	g_ptr_array_free(ctx.warnings, TRUE);
 	if ((*color_managed = !!ctx.screen_profile))
@@ -793,8 +793,8 @@ read_wide_thumbnail(const char *path, const Stat *st, GError **error)
 	if (!thumbnail_uri)
 		return NULL;
 
-	cairo_surface_t *surface =
+	cairo_surface_t *surface = fiv_io_image_to_surface(
-		fiv_io_open(&(FivIoOpenContext){.uri = thumbnail_uri}, error);
+		fiv_io_open(&(FivIoOpenContext){.uri = thumbnail_uri}, error));
 	g_free(thumbnail_uri);
 	if (!surface)
 		return NULL;

fiv-view.c

@@ -1374,7 +1374,8 @@ open_without_swapping_in(FivView *self, const char *uri)
 	};
 
 	GError *error = NULL;
-	cairo_surface_t *surface = fiv_io_open(&ctx, &error);
+	cairo_surface_t *surface =
+		fiv_io_image_to_surface(fiv_io_open(&ctx, &error));
 	if (error) {
 		g_ptr_array_add(ctx.warnings, g_strdup(error->message));
 		g_error_free(error);

tools/benchmark-io.c

@@ -41,14 +41,14 @@ one_file(const char *filename)
 		.warnings = g_ptr_array_new_with_free_func(g_free),
 	};
 
-	cairo_surface_t *loaded_by_us = fiv_io_open(&ctx, NULL);
+	FivIoImage *loaded_by_us = fiv_io_open(&ctx, NULL);
 	g_clear_object(&file);
 	g_free((char *) ctx.uri);
 	g_ptr_array_free(ctx.warnings, TRUE);
 	if (!loaded_by_us)
 		return;
 
-	cairo_surface_destroy(loaded_by_us);
+	fiv_io_image_unref(loaded_by_us);
 	us = timestamp() - since_us;
 
 	double since_pixbuf = timestamp(), pixbuf = 0;