Adopt shorter identifiers

Also, slightly reformat the source code according to clang-format.

1 files changed, 122 insertions, 0 deletions

diff --git a/fiv-io.h b/fiv-io.h
new file mode 100644
index 0000000..5fbe276
--- /dev/null
+++ b/fiv-io.h
@@ -0,0 +1,122 @@
+//
+// fiv-io.h: image operations
+//
+// 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.
+//
+
+#pragma once
+
+#include <cairo.h>
+#include <gio/gio.h>
+#include <glib.h>
+
+extern const char *fiv_io_supported_media_types[];
+
+char **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;
+
+/// 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;
+
+cairo_surface_t *fiv_io_open(const gchar *path, GError **error);
+cairo_surface_t *fiv_io_open_from_data(
+	const char *data, size_t len, const gchar *path, GError **error);
+
+int fiv_io_filecmp(GFile *f1, GFile *f2);
+
+// --- Export ------------------------------------------------------------------
+
+/// Requires libwebp.
+/// If no exact frame is specified, this potentially creates an animation.
+gboolean fiv_io_save(cairo_surface_t *page, cairo_surface_t *frame,
+	const gchar *path, GError **error);
+
+// --- Metadata ----------------------------------------------------------------
+
+// https://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf Table 6
+typedef enum _FivIoOrientation {
+	FivIoOrientationUnknown   = 0,
+	FivIoOrientation0         = 1,
+	FivIoOrientationMirror0   = 2,
+	FivIoOrientation180       = 3,
+	FivIoOrientationMirror180 = 4,
+	FivIoOrientationMirror270 = 5,
+	FivIoOrientation90        = 6,
+	FivIoOrientationMirror90  = 7,
+	FivIoOrientation270       = 8
+} FivIoOrientation;
+
+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 gchar *path, GError **error);
+
+// --- Thumbnails --------------------------------------------------------------
+
+// And this is how you avoid glib-mkenums.
+typedef enum _FivIoThumbnailSize {
+#define FIV_IO_THUMBNAIL_SIZES(XX) \
+	XX(SMALL,  128, "normal") \
+	XX(NORMAL, 256, "large") \
+	XX(LARGE,  512, "x-large") \
+	XX(HUGE,  1024, "xx-large")
+#define XX(name, value, dir) FIV_IO_THUMBNAIL_SIZE_ ## name,
+	FIV_IO_THUMBNAIL_SIZES(XX)
+#undef XX
+	FIV_IO_THUMBNAIL_SIZE_COUNT,
+
+	FIV_IO_THUMBNAIL_SIZE_MIN = 0,
+	FIV_IO_THUMBNAIL_SIZE_MAX = FIV_IO_THUMBNAIL_SIZE_COUNT - 1
+} FivIoThumbnailSize;
+
+GType fiv_io_thumbnail_size_get_type(void) G_GNUC_CONST;
+#define FIV_TYPE_IO_THUMBNAIL_SIZE (fiv_io_thumbnail_size_get_type())
+
+typedef struct _FivIoThumbnailSizeInfo {
+	int size;                           ///< Nominal size in pixels
+	const char *thumbnail_spec_name;    ///< thumbnail-spec directory name
+} FivIoThumbnailSizeInfo;
+
+extern FivIoThumbnailSizeInfo
+	fiv_io_thumbnail_sizes[FIV_IO_THUMBNAIL_SIZE_COUNT];
+
+cairo_surface_t *fiv_io_lookup_thumbnail(
+	GFile *target, FivIoThumbnailSize size);