//
// fiv-io.c: image operations
//
// Copyright (c) 2021, Přemysl Eric Janouch
//
// 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
#include
#include
#include
#include
#include
// Colour management must be handled before RGB conversions.
#ifdef HAVE_LCMS2
#include
#endif // HAVE_LCMS2
#ifdef HAVE_JPEG_QS
#include
#include
// This library is tricky to build, simply make it work at all.
#define NO_SIMD
#include
#undef NO_SIMD
#endif // HAVE_JPEG_QS
#ifdef HAVE_LIBRAW
#include
#endif // HAVE_LIBRAW
#ifdef HAVE_LIBRSVG
#include
#endif // HAVE_LIBRSVG
#ifdef HAVE_XCURSOR
#include
#endif // HAVE_XCURSOR
#ifdef HAVE_LIBWEBP
#include
#include
#include
#include
#endif // HAVE_LIBWEBP
#ifdef HAVE_LIBHEIF
#include
#endif // HAVE_LIBHEIF
#ifdef HAVE_LIBTIFF
#include
#include
#endif // HAVE_LIBTIFF
#ifdef HAVE_GDKPIXBUF
#include
#include
#endif // HAVE_GDKPIXBUF
#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"
#include "fiv-io.h"
#include "xdg.h"
#if CAIRO_VERSION >= 11702 && X11_ACTUALLY_SUPPORTS_RGBA128F_OR_WE_USE_OPENGL
#define FIV_CAIRO_RGBA128F
#endif
// A subset of shared-mime-info that produces an appropriate list of
// file extensions. Chiefly motivated by the suckiness of raw photo formats:
// someone else will maintain the list of file extensions for us.
const char *fiv_io_supported_media_types[] = {
"image/bmp",
"image/gif",
"image/png",
"image/jpeg",
#ifdef HAVE_LIBRAW
"image/x-dcraw",
#endif // HAVE_LIBRAW
#ifdef HAVE_LIBRSVG
"image/svg+xml",
#endif // HAVE_LIBRSVG
#ifdef HAVE_XCURSOR
"image/x-xcursor",
#endif // HAVE_XCURSOR
#ifdef HAVE_LIBWEBP
"image/webp",
#endif // HAVE_LIBWEBP
#ifdef HAVE_LIBHEIF
"image/heic",
"image/heif",
"image/avif",
#endif // HAVE_LIBHEIF
#ifdef HAVE_LIBTIFF
"image/tiff",
#endif // HAVE_LIBTIFF
NULL
};
char **
fiv_io_all_supported_media_types(void)
{
GPtrArray *types = g_ptr_array_new();
for (const char **p = fiv_io_supported_media_types; *p; p++)
g_ptr_array_add(types, g_strdup(*p));
#ifdef HAVE_GDKPIXBUF
GSList *formats = gdk_pixbuf_get_formats();
for (GSList *iter = formats; iter; iter = iter->next) {
gchar **subtypes = gdk_pixbuf_format_get_mime_types(iter->data);
for (gchar **p = subtypes; *p; p++)
g_ptr_array_add(types, *p);
g_free(subtypes);
}
g_slist_free(formats);
#endif // HAVE_GDKPIXBUF
g_ptr_array_add(types, NULL);
return (char **) g_ptr_array_free(types, FALSE);
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#define FIV_IO_ERROR fiv_io_error_quark()
G_DEFINE_QUARK(fiv-io-error-quark, fiv_io_error)
enum FivIoError {
FIV_IO_ERROR_OPEN
};
static void
set_error(GError **error, const char *message)
{
g_set_error_literal(error, FIV_IO_ERROR, FIV_IO_ERROR_OPEN, message);
}
static bool
try_append_page(cairo_surface_t *surface, cairo_surface_t **result,
cairo_surface_t **result_tail)
{
if (!surface)
return false;
if (*result) {
cairo_surface_set_user_data(*result_tail, &fiv_io_key_page_next,
surface, (cairo_destroy_func_t) cairo_surface_destroy);
cairo_surface_set_user_data(
surface, &fiv_io_key_page_previous, *result_tail, NULL);
*result_tail = surface;
} else {
*result = *result_tail = surface;
}
return true;
}
// --- Colour management -------------------------------------------------------
FivIoProfile
fiv_io_profile_new(const void *data, size_t len)
{
#ifdef HAVE_LCMS2
return cmsOpenProfileFromMem(data, len);
#else
(void) data;
(void) len;
return NULL;
#endif
}
FivIoProfile
fiv_io_profile_new_sRGB(void)
{
#ifdef HAVE_LCMS2
return cmsCreate_sRGBProfile();
#else
return NULL;
#endif
}
void
fiv_io_profile_free(FivIoProfile self)
{
#ifdef HAVE_LCMS2
cmsCloseProfile(self);
#else
(void) self;
#endif
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// TODO(p): In general, try to use CAIRO_FORMAT_RGB30 or CAIRO_FORMAT_RGBA128F.
#define FIV_IO_LCMS2_ARGB \
(G_BYTE_ORDER == G_LITTLE_ENDIAN ? TYPE_BGRA_8 : TYPE_ARGB_8)
// CAIRO_STRIDE_ALIGNMENT is 4 bytes, so there will be no padding with
// ARGB/BGRA/XRGB/BGRX.
static void
trivial_cmyk_to_host_byte_order_argb(unsigned char *p, int len)
{
// This CMYK handling has been seen in gdk-pixbuf/JPEG, GIMP/JPEG, skcms.
// 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];
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
p[0] = k * y / 255;
p[1] = k * m / 255;
p[2] = k * c / 255;
p[3] = 255;
#else
p[3] = k * y / 255;
p[2] = k * m / 255;
p[1] = k * c / 255;
p[0] = 255;
#endif
p += 4;
}
}
static void
fiv_io_profile_cmyk(
cairo_surface_t *surface, FivIoProfile source, FivIoProfile target)
{
unsigned char *data = cairo_image_surface_get_data(surface);
int w = cairo_image_surface_get_width(surface);
int h = cairo_image_surface_get_height(surface);
#ifndef HAVE_LCMS2
(void) source;
(void) target;
#else
cmsHTRANSFORM transform = NULL;
if (source && target) {
transform = cmsCreateTransform(source, TYPE_CMYK_8_REV, target,
FIV_IO_LCMS2_ARGB, INTENT_PERCEPTUAL, 0);
}
if (transform) {
cmsDoTransform(transform, data, data, w * h);
cmsDeleteTransform(transform);
return;
}
#endif
trivial_cmyk_to_host_byte_order_argb(data, w * h);
}
static void
fiv_io_profile_xrgb(
cairo_surface_t *surface, FivIoProfile source, FivIoProfile target)
{
#ifndef HAVE_LCMS2
(void) surface;
(void) source;
(void) target;
#else
unsigned char *data = cairo_image_surface_get_data(surface);
int w = cairo_image_surface_get_width(surface);
int h = cairo_image_surface_get_height(surface);
// TODO(p): We should make this optional.
cmsHPROFILE src_fallback = NULL;
if (target && !source)
source = src_fallback = cmsCreate_sRGBProfile();
cmsHTRANSFORM transform = NULL;
if (source && target) {
transform = cmsCreateTransform(source, FIV_IO_LCMS2_ARGB, target,
FIV_IO_LCMS2_ARGB, INTENT_PERCEPTUAL, 0);
}
if (transform) {
cmsDoTransform(transform, data, data, w * h);
cmsDeleteTransform(transform);
}
if (src_fallback)
cmsCloseProfile(src_fallback);
#endif
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static void
fiv_io_profile_finalize_page(cairo_surface_t *page, FivIoProfile target)
{
GBytes *bytes = NULL;
gsize len = 0;
gconstpointer p = NULL;
FivIoProfile source = NULL;
if ((bytes = cairo_surface_get_user_data(page, &fiv_io_key_icc)) &&
(p = g_bytes_get_data(bytes, &len)))
source = fiv_io_profile_new(p, len);
// TODO(p): Animations need to be composited in a linear colour space.
for (cairo_surface_t *frame = page; frame != NULL;
frame = cairo_surface_get_user_data(frame, &fiv_io_key_frame_next))
fiv_io_profile_xrgb(frame, source, target);
if (source)
fiv_io_profile_free(source);
}
// TODO(p): Offer better integration, upgrade the bit depth if appropriate.
static cairo_surface_t *
fiv_io_profile_finalize(cairo_surface_t *image, FivIoProfile target)
{
if (!image || !target)
return image;
for (cairo_surface_t *page = image; page != NULL;
page = cairo_surface_get_user_data(page, &fiv_io_key_page_next)) {
// TODO(p): 1. un/premultiply ARGB, 2. do colour management
// early enough, so that no avoidable increase of quantization error
// occurs beforehands, and also for correct alpha compositing.
// FIXME: This assumes that if the first frame is opaque, they all are.
if (cairo_image_surface_get_format(page) == CAIRO_FORMAT_RGB24)
fiv_io_profile_finalize_page(page, target);
}
return image;
}
// --- Wuffs -------------------------------------------------------------------
// From libwebp, verified to exactly match [x * a / 255].
#define PREMULTIPLY8(a, x) (((uint32_t) (x) * (uint32_t) (a) * 32897U) >> 23)
static bool
pull_passthrough(const wuffs_base__more_information *minfo,
wuffs_base__io_buffer *src, wuffs_base__io_buffer *dst, GError **error)
{
wuffs_base__range_ie_u64 r =
wuffs_base__more_information__metadata_raw_passthrough__range(minfo);
if (wuffs_base__range_ie_u64__is_empty(&r))
return true;
// This should currently be zero, because we read files all at once.
uint64_t pos = src->meta.pos;
if (pos > r.min_incl ||
wuffs_base__u64__sat_sub(r.max_excl, pos) > src->meta.wi) {
set_error(error, "metadata is outside the read buffer");
return false;
}
// Mimic WUFFS_BASE__MORE_INFORMATION__FLAVOR__METADATA_RAW_TRANSFORM.
*dst = wuffs_base__make_io_buffer(src->data,
wuffs_base__make_io_buffer_meta(
wuffs_base__u64__sat_sub(r.max_excl, pos),
wuffs_base__u64__sat_sub(r.min_incl, pos), pos, TRUE));
// Seeking to the end of it seems to be a requirement in decode_gif.wuffs.
// Just not in case the block was empty. :^)
src->meta.ri = dst->meta.wi;
return true;
}
static GBytes *
pull_metadata(wuffs_base__image_decoder *dec, wuffs_base__io_buffer *src,
wuffs_base__more_information *minfo, GError **error)
{
uint8_t buf[8192] = {};
GByteArray *array = g_byte_array_new();
while (true) {
*minfo = wuffs_base__empty_more_information();
wuffs_base__io_buffer dst = wuffs_base__ptr_u8__writer(buf, sizeof buf);
wuffs_base__status status =
wuffs_base__image_decoder__tell_me_more(dec, &dst, minfo, src);
switch (minfo->flavor) {
case 0:
// Most likely as a result of an error, we'll handle that below.
case WUFFS_BASE__MORE_INFORMATION__FLAVOR__METADATA_RAW_TRANSFORM:
// Wuffs is reading it into the buffer.
case WUFFS_BASE__MORE_INFORMATION__FLAVOR__METADATA_PARSED:
// Use Wuffs accessor functions in the caller.
break;
default:
set_error(error, "Wuffs metadata API incompatibility");
goto fail;
case WUFFS_BASE__MORE_INFORMATION__FLAVOR__METADATA_RAW_PASSTHROUGH:
// The insane case: error checking really should come first,
// and it can say "even more information". See decode_gif.wuffs.
if (!pull_passthrough(minfo, src, &dst, error))
goto fail;
}
g_byte_array_append(array, wuffs_base__io_buffer__reader_pointer(&dst),
wuffs_base__io_buffer__reader_length(&dst));
if (wuffs_base__status__is_ok(&status))
return g_byte_array_free_to_bytes(array);
if (status.repr != wuffs_base__suspension__even_more_information &&
status.repr != wuffs_base__suspension__short_write) {
set_error(error, wuffs_base__status__message(&status));
goto fail;
}
}
fail:
g_byte_array_unref(array);
return NULL;
}
struct load_wuffs_frame_context {
wuffs_base__image_decoder *dec; ///< Wuffs decoder abstraction
wuffs_base__io_buffer *src; ///< Wuffs source buffer
wuffs_base__image_config cfg; ///< Wuffs image configuration
wuffs_base__slice_u8 workbuf; ///< Work buffer for Wuffs
wuffs_base__frame_config last_fc; ///< Previous frame configuration
uint32_t width; ///< Copied from cfg.pixcfg
uint32_t height; ///< Copied from cfg.pixcfg
cairo_format_t cairo_format; ///< Target format for surfaces
bool pack_16_10; ///< Custom copying swizzle for RGB30
bool expand_16_float; ///< Custom copying swizzle for RGBA128F
GBytes *meta_exif; ///< Reference-counted Exif
GBytes *meta_iccp; ///< Reference-counted ICC profile
GBytes *meta_xmp; ///< Reference-counted XMP
cairo_surface_t *result; ///< The resulting surface (referenced)
cairo_surface_t *result_tail; ///< The final animation frame
};
static bool
load_wuffs_frame(struct load_wuffs_frame_context *ctx, GError **error)
{
wuffs_base__frame_config fc = {};
wuffs_base__status status =
wuffs_base__image_decoder__decode_frame_config(ctx->dec, &fc, ctx->src);
if (status.repr == wuffs_base__note__end_of_data && ctx->result)
return false;
if (!wuffs_base__status__is_ok(&status)) {
set_error(error, wuffs_base__status__message(&status));
return false;
}
bool success = false;
unsigned char *targetbuf = NULL;
cairo_surface_t *surface =
cairo_image_surface_create(ctx->cairo_format, ctx->width, ctx->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));
goto fail;
}
// 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.
unsigned char *surface_data = cairo_image_surface_get_data(surface);
int surface_stride = cairo_image_surface_get_stride(surface);
wuffs_base__pixel_buffer pb = {0};
if (ctx->expand_16_float) {
uint32_t targetbuf_size = ctx->height * ctx->width * 64;
targetbuf = g_malloc(targetbuf_size);
status = wuffs_base__pixel_buffer__set_from_slice(&pb, &ctx->cfg.pixcfg,
wuffs_base__make_slice_u8(targetbuf, targetbuf_size));
} else if (ctx->pack_16_10) {
uint32_t targetbuf_size = ctx->height * ctx->width * 16;
targetbuf = g_malloc(targetbuf_size);
status = wuffs_base__pixel_buffer__set_from_slice(&pb, &ctx->cfg.pixcfg,
wuffs_base__make_slice_u8(targetbuf, targetbuf_size));
} else {
status = wuffs_base__pixel_buffer__set_from_slice(&pb, &ctx->cfg.pixcfg,
wuffs_base__make_slice_u8(surface_data,
surface_stride * cairo_image_surface_get_height(surface)));
}
if (!wuffs_base__status__is_ok(&status)) {
set_error(error, wuffs_base__status__message(&status));
goto fail;
}
// Starting to modify pixel data directly. Probably an unnecessary call.
cairo_surface_flush(surface);
status = wuffs_base__image_decoder__decode_frame(ctx->dec, &pb, ctx->src,
WUFFS_BASE__PIXEL_BLEND__SRC, ctx->workbuf, NULL);
if (!wuffs_base__status__is_ok(&status)) {
set_error(error, wuffs_base__status__message(&status));
goto fail;
}
if (ctx->expand_16_float) {
g_debug("Wuffs to Cairo RGBA128F");
uint16_t *in = (uint16_t *) targetbuf;
float *out = (float *) surface_data;
for (uint32_t y = 0; y < ctx->height; y++) {
for (uint32_t x = 0; x < ctx->width; x++) {
float b = *in++ / 65535., g = *in++ / 65535.,
r = *in++ / 65535., a = *in++ / 65535.;
*out++ = r * a;
*out++ = g * a;
*out++ = b * a;
*out++ = a;
}
}
} else if (ctx->pack_16_10) {
g_debug("Wuffs to Cairo RGB30");
uint16_t *in = (uint16_t *) targetbuf;
uint32_t *out = (uint32_t *) surface_data;
for (uint32_t y = 0; y < ctx->height; y++) {
for (uint32_t x = 0; x < ctx->width; x++) {
uint32_t b = *in++, g = *in++, r = *in++, X = *in++;
*out++ = (X >> 14) << 30 |
(r >> 6) << 20 | (g >> 6) << 10 | (b >> 6);
}
}
}
// Pixel data has been written, need to let Cairo know.
cairo_surface_mark_dirty(surface);
// Single-frame images get a fast path, animations are are handled slowly:
if (wuffs_base__frame_config__index(&fc) > 0) {
// Copy the previous frame to a new surface.
cairo_surface_t *canvas = cairo_image_surface_create(
ctx->cairo_format, ctx->width, ctx->height);
int stride = cairo_image_surface_get_stride(canvas);
int height = cairo_image_surface_get_height(canvas);
memcpy(cairo_image_surface_get_data(canvas),
cairo_image_surface_get_data(ctx->result_tail), stride * height);
cairo_surface_mark_dirty(canvas);
// Apply that frame's disposal method.
wuffs_base__rect_ie_u32 bounds =
wuffs_base__frame_config__bounds(&ctx->last_fc);
wuffs_base__color_u32_argb_premul bg =
wuffs_base__frame_config__background_color(&ctx->last_fc);
double a = (bg >> 24) / 255., r = 0, g = 0, b = 0;
if (a) {
r = (uint8_t) (bg >> 16) / 255. / a;
g = (uint8_t) (bg >> 8) / 255. / a;
b = (uint8_t) (bg) / 255. / a;
}
cairo_t *cr = cairo_create(canvas);
switch (wuffs_base__frame_config__disposal(&ctx->last_fc)) {
case WUFFS_BASE__ANIMATION_DISPOSAL__RESTORE_BACKGROUND:
cairo_rectangle(cr, bounds.min_incl_x, bounds.min_incl_y,
bounds.max_excl_x - bounds.min_incl_x,
bounds.max_excl_y - bounds.min_incl_y);
cairo_set_source_rgba(cr, r, g, b, a);
cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
cairo_fill(cr);
break;
case WUFFS_BASE__ANIMATION_DISPOSAL__RESTORE_PREVIOUS:
// TODO(p): Implement, it seems tricky.
// Might need another surface to keep track of the state.
break;
}
// Paint the current frame over that, within its bounds.
bounds = wuffs_base__frame_config__bounds(&fc);
cairo_rectangle(cr, bounds.min_incl_x, bounds.min_incl_y,
bounds.max_excl_x - bounds.min_incl_x,
bounds.max_excl_y - bounds.min_incl_y);
cairo_clip(cr);
cairo_set_operator(cr,
wuffs_base__frame_config__overwrite_instead_of_blend(&fc)
? CAIRO_OPERATOR_SOURCE
: CAIRO_OPERATOR_OVER);
cairo_set_source_surface(cr, surface, 0, 0);
cairo_paint(cr);
cairo_destroy(cr);
cairo_surface_destroy(surface);
surface = canvas;
}
if (ctx->meta_exif)
cairo_surface_set_user_data(surface, &fiv_io_key_exif,
g_bytes_ref(ctx->meta_exif), (cairo_destroy_func_t) g_bytes_unref);
if (ctx->meta_iccp)
cairo_surface_set_user_data(surface, &fiv_io_key_icc,
g_bytes_ref(ctx->meta_iccp), (cairo_destroy_func_t) g_bytes_unref);
if (ctx->meta_xmp)
cairo_surface_set_user_data(surface, &fiv_io_key_xmp,
g_bytes_ref(ctx->meta_xmp), (cairo_destroy_func_t) g_bytes_unref);
cairo_surface_set_user_data(surface, &fiv_io_key_loops,
(void *) (uintptr_t) wuffs_base__image_decoder__num_animation_loops(
ctx->dec), NULL);
cairo_surface_set_user_data(surface, &fiv_io_key_frame_duration,
(void *) (intptr_t) (wuffs_base__frame_config__duration(&fc) /
WUFFS_BASE__FLICKS_PER_MILLISECOND), NULL);
cairo_surface_set_user_data(
surface, &fiv_io_key_frame_previous, ctx->result_tail, NULL);
if (ctx->result_tail)
cairo_surface_set_user_data(ctx->result_tail, &fiv_io_key_frame_next,
surface, (cairo_destroy_func_t) cairo_surface_destroy);
else
ctx->result = surface;
success = true;
ctx->result_tail = surface;
ctx->last_fc = fc;
fail:
if (!success) {
cairo_surface_destroy(surface);
g_clear_pointer(&ctx->result, cairo_surface_destroy);
ctx->result_tail = NULL;
}
g_free(targetbuf);
return success;
}
// 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)
{
struct load_wuffs_frame_context ctx = {.dec = dec, .src = &src};
// TODO(p): PNG also has sRGB and gAMA, as well as text chunks (Wuffs #58).
// The former two use WUFFS_BASE__MORE_INFORMATION__FLAVOR__METADATA_PARSED.
wuffs_base__image_decoder__set_report_metadata(
ctx.dec, WUFFS_BASE__FOURCC__EXIF, true);
wuffs_base__image_decoder__set_report_metadata(
ctx.dec, WUFFS_BASE__FOURCC__ICCP, true);
while (true) {
wuffs_base__status status =
wuffs_base__image_decoder__decode_image_config(
ctx.dec, &ctx.cfg, ctx.src);
if (wuffs_base__status__is_ok(&status))
break;
if (status.repr != wuffs_base__note__metadata_reported) {
set_error(error, wuffs_base__status__message(&status));
goto fail;
}
wuffs_base__more_information minfo = {};
GBytes *bytes = NULL;
if (!(bytes = pull_metadata(ctx.dec, ctx.src, &minfo, error)))
goto fail;
switch (wuffs_base__more_information__metadata__fourcc(&minfo)) {
case WUFFS_BASE__FOURCC__EXIF:
if (ctx.meta_exif) {
g_warning("ignoring repeated Exif");
break;
}
ctx.meta_exif = bytes;
continue;
case WUFFS_BASE__FOURCC__ICCP:
if (ctx.meta_iccp) {
g_warning("ignoring repeated ICC profile");
break;
}
ctx.meta_iccp = bytes;
continue;
case WUFFS_BASE__FOURCC__XMP:
if (ctx.meta_xmp) {
g_warning("ignoring repeated XMP");
break;
}
ctx.meta_xmp = bytes;
continue;
}
g_bytes_unref(bytes);
}
// This, at least currently, seems excessive.
if (!wuffs_base__image_config__is_valid(&ctx.cfg)) {
set_error(error, "invalid Wuffs image configuration");
goto fail;
}
// We need to check because of the Cairo API.
ctx.width = wuffs_base__pixel_config__width(&ctx.cfg.pixcfg);
ctx.height = wuffs_base__pixel_config__height(&ctx.cfg.pixcfg);
if (ctx.width > INT_MAX || ctx.height > INT_MAX) {
set_error(error, "image dimensions overflow");
goto fail;
}
// Wuffs maps tRNS to BGRA in `decoder.decode_trns?`, we should be fine.
// wuffs_base__pixel_format__transparency() doesn't reflect the image file.
// TODO(p): See if wuffs_base__image_config__first_frame_is_opaque() causes
// issues with animations, and eventually ensure an alpha-capable format.
bool opaque = wuffs_base__image_config__first_frame_is_opaque(&ctx.cfg);
// Wuffs' API is kind of awful--we want to catch deep RGB and deep grey.
wuffs_base__pixel_format srcfmt =
wuffs_base__pixel_config__pixel_format(&ctx.cfg.pixcfg);
uint32_t bpp = wuffs_base__pixel_format__bits_per_pixel(&srcfmt);
// Cairo doesn't support transparency with RGB30, so no premultiplication.
ctx.pack_16_10 = opaque && (bpp > 24 || (bpp < 24 && bpp > 8));
#ifdef FIV_CAIRO_RGBA128F
ctx.expand_16_float = !opaque && (bpp > 24 || (bpp < 24 && bpp > 8));
#endif // FIV_CAIRO_RGBA128F
// In Wuffs, /doc/note/pixel-formats.md declares "memory order", which,
// for our purposes, means big endian, and BGRA results in 32-bit ARGB
// on most machines.
//
// XXX: WUFFS_BASE__PIXEL_FORMAT__ARGB_PREMUL is not expressible, only RGBA.
// Wuffs doesn't support big-endian architectures at all, we might want to
// fall back to spng in such cases, or do a second conversion.
uint32_t wuffs_format = WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL;
// CAIRO_FORMAT_ARGB32: "The 32-bit quantities are stored native-endian.
// Pre-multiplied alpha is used." CAIRO_FORMAT_RGB{24,30} are analogous.
ctx.cairo_format = CAIRO_FORMAT_ARGB32;
#ifdef FIV_CAIRO_RGBA128F
if (ctx.expand_16_float) {
wuffs_format = WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL_4X16LE;
ctx.cairo_format = CAIRO_FORMAT_RGBA128F;
} else
#endif // FIV_CAIRO_RGBA128F
if (ctx.pack_16_10) {
// TODO(p): Make Wuffs support A2RGB30 as a destination format;
// in general, 16-bit depth swizzlers are stubbed.
// See also wuffs_base__pixel_swizzler__prepare__*().
wuffs_format = WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL_4X16LE;
ctx.cairo_format = CAIRO_FORMAT_RGB30;
} else if (opaque) {
// BGRX doesn't have as wide swizzler support, namely in GIF.
wuffs_format = WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL;
ctx.cairo_format = CAIRO_FORMAT_RGB24;
}
wuffs_base__pixel_config__set(&ctx.cfg.pixcfg, wuffs_format,
WUFFS_BASE__PIXEL_SUBSAMPLING__NONE, ctx.width, ctx.height);
uint64_t workbuf_len_max_incl =
wuffs_base__image_decoder__workbuf_len(ctx.dec).max_incl;
if (workbuf_len_max_incl) {
ctx.workbuf = wuffs_base__malloc_slice_u8(malloc, workbuf_len_max_incl);
if (!ctx.workbuf.ptr) {
set_error(error, "failed to allocate a work buffer");
goto fail;
}
}
while (load_wuffs_frame(&ctx, error))
;
// Wrap the chain around, since our caller receives only one pointer.
if (ctx.result)
cairo_surface_set_user_data(
ctx.result, &fiv_io_key_frame_previous, ctx.result_tail, NULL);
fail:
free(ctx.workbuf.ptr);
g_clear_pointer(&ctx.meta_exif, g_bytes_unref);
g_clear_pointer(&ctx.meta_iccp, g_bytes_unref);
g_clear_pointer(&ctx.meta_xmp, g_bytes_unref);
return ctx.result;
}
static cairo_surface_t *
open_wuffs_using(wuffs_base__image_decoder *(*allocate)(),
const gchar *data, gsize len, FivIoProfile profile, 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 fiv_io_profile_finalize(surface, profile);
}
// --- JPEG --------------------------------------------------------------------
static GBytes *
parse_jpeg_metadata(cairo_surface_t *surface, const gchar *data, gsize len)
{
// Because the JPEG file format is simple, just do it manually.
// See: https://www.w3.org/Graphics/JPEG/itu-t81.pdf
enum {
APP0 = 0xE0,
APP1,
APP2,
RST0 = 0xD0,
RST1,
RST2,
RST3,
RST4,
RST5,
RST6,
RST7,
SOI = 0xD8,
EOI = 0xD9,
SOS = 0xDA,
TEM = 0x01,
};
GByteArray *exif = g_byte_array_new(), *icc = g_byte_array_new();
int icc_sequence = 0, icc_done = FALSE;
const guint8 *p = (const guint8 *) data, *end = p + len;
while (p + 3 < end && *p++ == 0xFF && *p != SOS && *p != EOI) {
// The previous byte is a fill byte, restart.
if (*p == 0xFF)
continue;
// These markers stand alone, not starting a marker segment.
guint8 marker = *p++;
switch (marker) {
case RST0:
case RST1:
case RST2:
case RST3:
case RST4:
case RST5:
case RST6:
case RST7:
case SOI:
case TEM:
continue;
}
// Do not bother validating the structure.
guint16 length = p[0] << 8 | p[1];
const guint8 *payload = p + 2;
if ((p += length) > end)
break;
// https://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf 4.7.2
// Adobe XMP Specification Part 3: Storage in Files, 2020/1, 1.1.3
// Not checking the padding byte is intentional.
if (marker == APP1 && p - payload >= 6 &&
!memcmp(payload, "Exif\0", 5) && !exif->len) {
payload += 6;
g_byte_array_append(exif, payload, p - payload);
}
// https://www.color.org/specification/ICC1v43_2010-12.pdf B.4
if (marker == APP2 && p - payload >= 14 &&
!memcmp(payload, "ICC_PROFILE\0", 12) && !icc_done &&
payload[12] == ++icc_sequence && payload[13] >= payload[12]) {
payload += 14;
g_byte_array_append(icc, payload, p - payload);
icc_done = payload[-1] == icc_sequence;
}
// TODO(p): Extract the main XMP segment.
}
if (exif->len)
cairo_surface_set_user_data(surface, &fiv_io_key_exif,
g_byte_array_free_to_bytes(exif),
(cairo_destroy_func_t) g_bytes_unref);
else
g_byte_array_free(exif, TRUE);
GBytes *icc_profile = NULL;
if (icc_done)
cairo_surface_set_user_data(surface, &fiv_io_key_icc,
(icc_profile = g_byte_array_free_to_bytes(icc)),
(cairo_destroy_func_t) g_bytes_unref);
else
g_byte_array_free(icc, TRUE);
return icc_profile;
}
static void
load_jpeg_finalize(cairo_surface_t *surface, bool cmyk,
FivIoProfile destination, const gchar *data, size_t len)
{
GBytes *icc_profile = parse_jpeg_metadata(surface, data, len);
FivIoProfile source = NULL;
if (icc_profile)
source = fiv_io_profile_new(
g_bytes_get_data(icc_profile, NULL), g_bytes_get_size(icc_profile));
if (cmyk)
fiv_io_profile_cmyk(surface, source, destination);
else
fiv_io_profile_xrgb(surface, source, destination);
if (source)
fiv_io_profile_free(source);
// Pixel data has been written, need to let Cairo know.
cairo_surface_mark_dirty(surface);
}
static cairo_surface_t *
open_libjpeg_turbo(
const gchar *data, gsize len, FivIoProfile profile, 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;
}
bool use_cmyk = colorspace == TJCS_CMYK || colorspace == TJCS_YCCK;
int pixel_format = use_cmyk
? TJPF_CMYK
: (G_BYTE_ORDER == G_LITTLE_ENDIAN ? TJPF_BGRX : TJPF_XRGB);
cairo_surface_t *surface =
cairo_image_surface_create(CAIRO_FORMAT_RGB24, 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)) {
if (tjGetErrorCode(dec) == TJERR_WARNING) {
g_warning("%s", tjGetErrorStr2(dec));
} else {
set_error(error, tjGetErrorStr2(dec));
cairo_surface_destroy(surface);
tjDestroy(dec);
return NULL;
}
}
load_jpeg_finalize(surface, use_cmyk, profile, data, len);
tjDestroy(dec);
return surface;
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#ifdef HAVE_JPEG_QS
struct libjpeg_error_mgr {
struct jpeg_error_mgr pub;
jmp_buf buf;
GError **error;
};
static void
libjpeg_error_exit(j_common_ptr cinfo)
{
struct libjpeg_error_mgr *err = (struct libjpeg_error_mgr *) cinfo->err;
char buf[JMSG_LENGTH_MAX] = "";
(*cinfo->err->format_message)(cinfo, buf);
set_error(err->error, buf);
longjmp(err->buf, 1);
}
static cairo_surface_t *
open_libjpeg_enhanced(
const gchar *data, gsize len, FivIoProfile profile, GError **error)
{
cairo_surface_t *volatile surface = NULL;
struct libjpeg_error_mgr jerr = {.error = error};
struct jpeg_decompress_struct cinfo = {.err = jpeg_std_error(&jerr.pub)};
jerr.pub.error_exit = libjpeg_error_exit;
if (setjmp(jerr.buf)) {
g_clear_pointer(&surface, cairo_surface_destroy);
jpeg_destroy_decompress(&cinfo);
return NULL;
}
jpeg_create_decompress(&cinfo);
jpeg_mem_src(&cinfo, (const unsigned char *) data, len);
(void) jpeg_read_header(&cinfo, true);
bool use_cmyk = cinfo.jpeg_color_space == JCS_CMYK ||
cinfo.jpeg_color_space == JCS_YCCK;
if (use_cmyk)
cinfo.out_color_space = JCS_CMYK;
else if (G_BYTE_ORDER == G_BIG_ENDIAN)
cinfo.out_color_space = JCS_EXT_XRGB;
else
cinfo.out_color_space = JCS_EXT_BGRX;
jpeg_calc_output_dimensions(&cinfo);
int width = cinfo.output_width;
int height = cinfo.output_height;
surface = cairo_image_surface_create(CAIRO_FORMAT_RGB24, 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));
longjmp(jerr.buf, 1);
}
unsigned char *surface_data = cairo_image_surface_get_data(surface);
int surface_stride = cairo_image_surface_get_stride(surface);
JSAMPARRAY lines = (*cinfo.mem->alloc_small)(
(j_common_ptr) &cinfo, JPOOL_IMAGE, sizeof *lines * height);
for (int i = 0; i < height; i++)
lines[i] = surface_data + i * surface_stride;
// Go for the maximum quality setting.
jpegqs_control_t opts = {
.flags = JPEGQS_DIAGONALS | JPEGQS_JOINT_YUV | JPEGQS_UPSAMPLE_UV,
.threads = g_get_num_processors(),
.niter = 3,
};
(void) jpegqs_start_decompress(&cinfo, &opts);
while (cinfo.output_scanline < cinfo.output_height)
(void) jpeg_read_scanlines(&cinfo, lines + cinfo.output_scanline,
cinfo.output_height - cinfo.output_scanline);
if (cinfo.out_color_space == JCS_CMYK)
trivial_cmyk_to_host_byte_order_argb(
surface_data, cinfo.output_width * cinfo.output_height);
(void) jpegqs_finish_decompress(&cinfo);
load_jpeg_finalize(surface, use_cmyk, profile, data, len);
jpeg_destroy_decompress(&cinfo);
return surface;
}
#else
#define open_libjpeg_enhanced open_libjpeg_turbo
#endif
// --- Optional dependencies ---------------------------------------------------
#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 ---------------------------------------------------------
#ifdef HAVE_LIBRSVG // --------------------------------------------------------
#ifdef FIV_RSVG_DEBUG
#include
#include
#endif
// FIXME: librsvg rasterizes filters, so this method isn't fully appropriate.
static cairo_surface_t *
open_librsvg(const gchar *data, gsize len, const gchar *path, GError **error)
{
GFile *base_file = g_file_new_for_path(path);
GInputStream *is = g_memory_input_stream_new_from_data(data, len, NULL);
RsvgHandle *handle = rsvg_handle_new_from_stream_sync(
is, base_file, RSVG_HANDLE_FLAG_KEEP_IMAGE_DATA, NULL, error);
g_object_unref(base_file);
g_object_unref(is);
if (!handle)
return NULL;
// TODO(p): Acquire this from somewhere else.
rsvg_handle_set_dpi(handle, 96);
double w = 0, h = 0;
#if LIBRSVG_CHECK_VERSION(2, 51, 0)
if (!rsvg_handle_get_intrinsic_size_in_pixels(handle, &w, &h)) {
#else
RsvgDimensionData dd = {};
rsvg_handle_get_dimensions(handle, &dd);
if ((w = dd.width) <= 0 || (h = dd.height) <= 0) {
#endif
RsvgRectangle viewbox = {};
gboolean has_viewport = FALSE;
rsvg_handle_get_intrinsic_dimensions(
handle, NULL, NULL, NULL, NULL, &has_viewport, &viewbox);
if (!has_viewport) {
set_error(error, "cannot compute pixel dimensions");
g_object_unref(handle);
return NULL;
}
w = viewbox.width;
h = viewbox.height;
}
cairo_rectangle_t extents = {
.x = 0, .y = 0, .width = ceil(w), .height = ceil(h)};
cairo_surface_t *surface =
cairo_recording_surface_create(CAIRO_CONTENT_COLOR_ALPHA, &extents);
#ifdef FIV_RSVG_DEBUG
cairo_device_t *script = cairo_script_create("cairo.script");
cairo_surface_t *tee =
cairo_script_surface_create_for_target(script, surface);
cairo_t *cr = cairo_create(tee);
cairo_device_destroy(script);
cairo_surface_destroy(tee);
#else
cairo_t *cr = cairo_create(surface);
#endif
RsvgRectangle viewport = {.x = 0, .y = 0, .width = w, .height = h};
if (!rsvg_handle_render_document(handle, cr, &viewport, error)) {
cairo_surface_destroy(surface);
cairo_destroy(cr);
g_object_unref(handle);
return NULL;
}
cairo_destroy(cr);
g_object_unref(handle);
#ifdef FIV_RSVG_DEBUG
cairo_surface_t *svg = cairo_svg_surface_create("cairo.svg", w, h);
cr = cairo_create(svg);
cairo_set_source_surface(cr, surface, 0, 0);
cairo_paint(cr);
cairo_destroy(cr);
cairo_surface_destroy(svg);
cairo_surface_t *png =
cairo_image_surface_create(CAIRO_FORMAT_ARGB32, w * 10, h * 10);
cr = cairo_create(png);
cairo_scale(cr, 10, 10);
cairo_set_source_surface(cr, surface, 0, 0);
cairo_paint(cr);
cairo_destroy(cr);
cairo_surface_write_to_png(png, "cairo.png");
cairo_surface_destroy(png);
#endif
return surface;
}
#endif // HAVE_LIBRSVG --------------------------------------------------------
#ifdef HAVE_XCURSOR //---------------------------------------------------------
// fmemopen is part of POSIX-1.2008, this exercise is technically unnecessary.
// libXcursor checks for EOF rather than -1, it may eat your hamster.
struct fiv_io_xcursor {
XcursorFile parent;
unsigned char *data;
long position, len;
};
static int
fiv_io_xcursor_read(XcursorFile *file, unsigned char *buf, int len)
{
struct fiv_io_xcursor *fix = (struct fiv_io_xcursor *) file;
if (fix->position < 0 || fix->position > fix->len) {
errno = EOVERFLOW;
return -1;
}
long n = MIN(fix->len - fix->position, len);
if (n > G_MAXINT) {
errno = EIO;
return -1;
}
memcpy(buf, fix->data + fix->position, n);
fix->position += n;
return n;
}
static int
fiv_io_xcursor_write(G_GNUC_UNUSED XcursorFile *file,
G_GNUC_UNUSED unsigned char *buf, G_GNUC_UNUSED int len)
{
errno = EBADF;
return -1;
}
static int
fiv_io_xcursor_seek(XcursorFile *file, long offset, int whence)
{
struct fiv_io_xcursor *fix = (struct fiv_io_xcursor *) file;
switch (whence) {
case SEEK_SET:
fix->position = offset;
break;
case SEEK_CUR:
fix->position += offset;
break;
case SEEK_END:
fix->position = fix->len + offset;
break;
default:
errno = EINVAL;
return -1;
}
// This is technically too late for fseek(), but libXcursor doesn't care.
if (fix->position < 0) {
errno = EINVAL;
return -1;
}
return fix->position;
}
static const XcursorFile fiv_io_xcursor_adaptor = {
.closure = NULL,
.read = fiv_io_xcursor_read,
.write = fiv_io_xcursor_write,
.seek = fiv_io_xcursor_seek,
};
static cairo_surface_t *
open_xcursor(const gchar *data, gsize len, GError **error)
{
if (len > G_MAXLONG) {
set_error(error, "size overflow");
return NULL;
}
struct fiv_io_xcursor file = {
.parent = fiv_io_xcursor_adaptor,
.data = (unsigned char *) data,
.position = 0,
.len = len,
};
XcursorImages *images = XcursorXcFileLoadAllImages(&file.parent);
if (!images) {
set_error(error, "general failure");
return NULL;
}
// Interpret cursors as animated pages.
cairo_surface_t *pages = NULL, *frames_head = NULL, *frames_tail = NULL;
// XXX: Assuming that all "nominal sizes" have the same dimensions.
XcursorDim last_nominal = -1;
for (int i = 0; i < images->nimage; i++) {
XcursorImage *image = images->images[i];
// The library automatically byte swaps in _XcursorReadImage().
cairo_surface_t *surface = cairo_image_surface_create_for_data(
(unsigned char *) image->pixels, CAIRO_FORMAT_ARGB32,
image->width, image->height, image->width * sizeof *image->pixels);
cairo_surface_set_user_data(surface, &fiv_io_key_frame_duration,
(void *) (intptr_t) image->delay, NULL);
if (pages && image->size == last_nominal) {
cairo_surface_set_user_data(
surface, &fiv_io_key_frame_previous, frames_tail, NULL);
cairo_surface_set_user_data(frames_tail, &fiv_io_key_frame_next,
surface, (cairo_destroy_func_t) cairo_surface_destroy);
} else if (frames_head) {
cairo_surface_set_user_data(
frames_head, &fiv_io_key_frame_previous, frames_tail, NULL);
cairo_surface_set_user_data(frames_head, &fiv_io_key_page_next,
surface, (cairo_destroy_func_t) cairo_surface_destroy);
cairo_surface_set_user_data(
surface, &fiv_io_key_page_previous, frames_head, NULL);
frames_head = surface;
} else {
pages = frames_head = surface;
}
frames_tail = surface;
last_nominal = image->size;
}
if (!pages) {
XcursorImagesDestroy(images);
return NULL;
}
// Wrap around animations in the last page.
cairo_surface_set_user_data(
frames_head, &fiv_io_key_frame_previous, frames_tail, NULL);
// There is no need to copy data, assign it to the surface.
static cairo_user_data_key_t key = {};
cairo_surface_set_user_data(
pages, &key, images, (cairo_destroy_func_t) XcursorImagesDestroy);
// Do not bother doing colour correction, there is no correct rendering.
return pages;
}
#endif // HAVE_XCURSOR --------------------------------------------------------
#ifdef HAVE_LIBWEBP //---------------------------------------------------------
static cairo_surface_t *
load_libwebp_nonanimated(
WebPDecoderConfig *config, const WebPData *wd, GError **error)
{
cairo_surface_t *surface = cairo_image_surface_create(
config->input.has_alpha ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24,
config->input.width, config->input.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);
return NULL;
}
config->options.use_threads = true;
config->output.width = config->input.width;
config->output.height = config->input.height;
config->output.is_external_memory = true;
config->output.u.RGBA.rgba = cairo_image_surface_get_data(surface);
config->output.u.RGBA.stride = cairo_image_surface_get_stride(surface);
config->output.u.RGBA.size =
config->output.u.RGBA.stride * cairo_image_surface_get_height(surface);
if (G_BYTE_ORDER == G_LITTLE_ENDIAN)
config->output.colorspace = MODE_bgrA;
else
config->output.colorspace = MODE_Argb;
VP8StatusCode err = 0;
if ((err = WebPDecode(wd->bytes, wd->size, config))) {
set_error(error, "WebP decoding error");
cairo_surface_destroy(surface);
return NULL;
}
cairo_surface_mark_dirty(surface);
return surface;
}
static cairo_surface_t *
load_libwebp_frame(WebPAnimDecoder *dec, const WebPAnimInfo *info,
int *last_timestamp, GError **error)
{
uint8_t *buf = NULL;
int timestamp = 0;
if (!WebPAnimDecoderGetNext(dec, &buf, ×tamp)) {
set_error(error, "WebP decoding error");
return NULL;
}
bool is_opaque = (info->bgcolor & 0xFF) == 0xFF;
uint64_t area = info->canvas_width * info->canvas_height;
cairo_surface_t *surface = cairo_image_surface_create(
is_opaque ? CAIRO_FORMAT_RGB24 : CAIRO_FORMAT_ARGB32,
info->canvas_width, info->canvas_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);
return NULL;
}
uint32_t *dst = (uint32_t *) cairo_image_surface_get_data(surface);
if (G_BYTE_ORDER == G_LITTLE_ENDIAN) {
memcpy(dst, buf, area * sizeof *dst);
} else {
uint32_t *src = (uint32_t *) buf;
for (uint64_t i = 0; i < area; i++)
*dst++ = GUINT32_FROM_LE(*src++);
}
cairo_surface_mark_dirty(surface);
// This API is confusing and awkward.
cairo_surface_set_user_data(surface, &fiv_io_key_frame_duration,
(void *) (intptr_t) (timestamp - *last_timestamp), NULL);
*last_timestamp = timestamp;
return surface;
}
static cairo_surface_t *
load_libwebp_animated(const WebPData *wd, GError **error)
{
WebPAnimDecoderOptions options = {};
WebPAnimDecoderOptionsInit(&options);
options.use_threads = true;
options.color_mode = MODE_bgrA;
WebPAnimInfo info = {};
WebPAnimDecoder *dec = WebPAnimDecoderNew(wd, &options);
WebPAnimDecoderGetInfo(dec, &info);
cairo_surface_t *frames = NULL, *frames_tail = NULL;
if (info.canvas_width > INT_MAX || info.canvas_height > INT_MAX) {
set_error(error, "image dimensions overflow");
goto fail;
}
int last_timestamp = 0;
while (WebPAnimDecoderHasMoreFrames(dec)) {
cairo_surface_t *surface =
load_libwebp_frame(dec, &info, &last_timestamp, error);
if (!surface) {
g_clear_pointer(&frames, cairo_surface_destroy);
goto fail;
}
if (frames_tail)
cairo_surface_set_user_data(frames_tail, &fiv_io_key_frame_next,
surface, (cairo_destroy_func_t) cairo_surface_destroy);
else
frames = surface;
cairo_surface_set_user_data(
surface, &fiv_io_key_frame_previous, frames_tail, NULL);
frames_tail = surface;
}
if (frames) {
cairo_surface_set_user_data(
frames, &fiv_io_key_frame_previous, frames_tail, NULL);
} else {
set_error(error, "the animation has no frames");
g_clear_pointer(&frames, cairo_surface_destroy);
}
fail:
WebPAnimDecoderDelete(dec);
return frames;
}
static cairo_surface_t *
open_libwebp(const gchar *data, gsize len, const gchar *path,
FivIoProfile profile, GError **error)
{
// It is wholly zero-initialized by libwebp.
WebPDecoderConfig config = {};
if (!WebPInitDecoderConfig(&config)) {
set_error(error, "libwebp version mismatch");
return NULL;
}
// TODO(p): Differentiate between a bad WebP, and not a WebP.
VP8StatusCode err = 0;
WebPData wd = {.bytes = (const uint8_t *) data, .size = len};
if ((err = WebPGetFeatures(wd.bytes, wd.size, &config.input))) {
set_error(error, "WebP decoding error");
return NULL;
}
cairo_surface_t *result = config.input.has_animation
? load_libwebp_animated(&wd, error)
: load_libwebp_nonanimated(&config, &wd, error);
if (!result)
goto fail;
// Of course everything has to use a different abstraction.
WebPDemuxer *demux = WebPDemux(&wd);
if (!demux) {
g_warning("%s: %s", path, "demux failure");
goto fail;
}
// Releasing the demux chunk iterator is actually a no-op.
WebPChunkIterator chunk_iter = {};
uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
if ((flags & EXIF_FLAG) &&
WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter)) {
cairo_surface_set_user_data(result, &fiv_io_key_exif,
g_bytes_new(chunk_iter.chunk.bytes, chunk_iter.chunk.size),
(cairo_destroy_func_t) g_bytes_unref);
WebPDemuxReleaseChunkIterator(&chunk_iter);
}
if ((flags & ICCP_FLAG) &&
WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter)) {
cairo_surface_set_user_data(result, &fiv_io_key_icc,
g_bytes_new(chunk_iter.chunk.bytes, chunk_iter.chunk.size),
(cairo_destroy_func_t) g_bytes_unref);
WebPDemuxReleaseChunkIterator(&chunk_iter);
}
if ((flags & XMP_FLAG) &&
WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter)) {
cairo_surface_set_user_data(result, &fiv_io_key_xmp,
g_bytes_new(chunk_iter.chunk.bytes, chunk_iter.chunk.size),
(cairo_destroy_func_t) g_bytes_unref);
WebPDemuxReleaseChunkIterator(&chunk_iter);
}
if (flags & ANIMATION_FLAG) {
cairo_surface_set_user_data(result, &fiv_io_key_loops,
(void *) (uintptr_t) WebPDemuxGetI(demux, WEBP_FF_LOOP_COUNT),
NULL);
}
WebPDemuxDelete(demux);
fail:
WebPFreeDecBuffer(&config.output);
return fiv_io_profile_finalize(result, profile);
}
#endif // HAVE_LIBWEBP --------------------------------------------------------
#ifdef HAVE_LIBHEIF //---------------------------------------------------------
static cairo_surface_t *
load_libheif_image(struct heif_image_handle *handle, GError **error)
{
cairo_surface_t *surface = NULL;
int has_alpha = heif_image_handle_has_alpha_channel(handle);
int bit_depth = heif_image_handle_get_luma_bits_per_pixel(handle);
if (bit_depth < 0) {
set_error(error, "undefined bit depth");
goto fail;
}
// Setting `convert_hdr_to_8bit` seems to be a no-op for RGBA32/64.
struct heif_decoding_options *opts = heif_decoding_options_alloc();
// TODO(p): We can get 16-bit depth, in reality most likely 10-bit.
struct heif_image *image = NULL;
struct heif_error err = heif_decode_image(handle, &image,
heif_colorspace_RGB, heif_chroma_interleaved_RGBA, opts);
if (err.code != heif_error_Ok) {
set_error(error, err.message);
goto fail_decode;
}
int w = heif_image_get_width(image, heif_channel_interleaved);
int h = heif_image_get_height(image, heif_channel_interleaved);
surface = cairo_image_surface_create(
has_alpha ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24, w, h);
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);
surface = NULL;
goto fail_process;
}
// As of writing, the library is using 16-byte alignment, unlike Cairo.
int src_stride = 0;
const uint8_t *src = heif_image_get_plane_readonly(
image, heif_channel_interleaved, &src_stride);
int dst_stride = cairo_image_surface_get_stride(surface);
const uint8_t *dst = cairo_image_surface_get_data(surface);
for (int y = 0; y < h; y++) {
uint32_t *dstp = (uint32_t *) (dst + dst_stride * y);
const uint32_t *srcp = (const uint32_t *) (src + src_stride * y);
for (int x = 0; x < w; x++) {
uint32_t rgba = g_ntohl(srcp[x]);
*dstp++ = rgba << 24 | rgba >> 8;
}
}
// TODO(p): Test real behaviour on real transparent images.
if (has_alpha && !heif_image_handle_is_premultiplied_alpha(handle)) {
for (int y = 0; y < h; y++) {
uint32_t *dstp = (uint32_t *) (dst + dst_stride * y);
for (int x = 0; x < w; x++) {
uint32_t argb = dstp[x], a = argb >> 24;
dstp[x] = a << 24 |
PREMULTIPLY8(a, 0xFF & (argb >> 16)) << 16 |
PREMULTIPLY8(a, 0xFF & (argb >> 8)) << 8 |
PREMULTIPLY8(a, 0xFF & argb);
}
}
}
heif_item_id exif_id = 0;
if (heif_image_handle_get_list_of_metadata_block_IDs(
handle, "Exif", &exif_id, 1)) {
size_t exif_len = heif_image_handle_get_metadata_size(handle, exif_id);
void *exif = g_malloc0(exif_len);
err = heif_image_handle_get_metadata(handle, exif_id, exif);
if (err.code) {
g_warning("%s", err.message);
g_free(exif);
} else {
cairo_surface_set_user_data(surface, &fiv_io_key_exif,
g_bytes_new_take(exif, exif_len),
(cairo_destroy_func_t) g_bytes_unref);
}
}
// https://loc.gov/preservation/digital/formats/fdd/fdd000526.shtml#factors
if (heif_image_handle_get_color_profile_type(handle) ==
heif_color_profile_type_prof) {
size_t icc_len = heif_image_handle_get_raw_color_profile_size(handle);
void *icc = g_malloc0(icc_len);
err = heif_image_handle_get_raw_color_profile(handle, icc);
if (err.code) {
g_warning("%s", err.message);
g_free(icc);
} else {
cairo_surface_set_user_data(surface, &fiv_io_key_icc,
g_bytes_new_take(icc, icc_len),
(cairo_destroy_func_t) g_bytes_unref);
}
}
cairo_surface_mark_dirty(surface);
fail_process:
heif_image_release(image);
fail_decode:
heif_decoding_options_free(opts);
fail:
return surface;
}
static void
load_libheif_aux_images(const gchar *path, struct heif_image_handle *top,
cairo_surface_t **result, cairo_surface_t **result_tail)
{
// Include the depth image, we have no special processing for it now.
int filter = LIBHEIF_AUX_IMAGE_FILTER_OMIT_ALPHA;
int n = heif_image_handle_get_number_of_auxiliary_images(top, filter);
heif_item_id *ids = g_malloc0_n(n, sizeof *ids);
n = heif_image_handle_get_list_of_auxiliary_image_IDs(top, filter, ids, n);
for (int i = 0; i < n; i++) {
struct heif_image_handle *handle = NULL;
struct heif_error err =
heif_image_handle_get_auxiliary_image_handle(top, ids[i], &handle);
if (err.code != heif_error_Ok) {
g_warning("%s: %s", path, err.message);
continue;
}
GError *e = NULL;
if (!try_append_page(
load_libheif_image(handle, &e), result, result_tail)) {
g_warning("%s: %s", path, e->message);
g_error_free(e);
}
heif_image_handle_release(handle);
}
g_free(ids);
}
static cairo_surface_t *
open_libheif(const gchar *data, gsize len, const gchar *path,
FivIoProfile profile, GError **error)
{
// libheif will throw C++ exceptions on allocation failures.
// The library is generally awful through and through.
struct heif_context *ctx = heif_context_alloc();
cairo_surface_t *result = NULL, *result_tail = NULL;
struct heif_error err;
err = heif_context_read_from_memory_without_copy(ctx, data, len, NULL);
if (err.code != heif_error_Ok) {
set_error(error, err.message);
goto fail_read;
}
int n = heif_context_get_number_of_top_level_images(ctx);
heif_item_id *ids = g_malloc0_n(n, sizeof *ids);
n = heif_context_get_list_of_top_level_image_IDs(ctx, ids, n);
for (int i = 0; i < n; i++) {
struct heif_image_handle *handle = NULL;
err = heif_context_get_image_handle(ctx, ids[i], &handle);
if (err.code != heif_error_Ok) {
g_warning("%s: %s", path, err.message);
continue;
}
GError *e = NULL;
if (!try_append_page(
load_libheif_image(handle, &e), &result, &result_tail)) {
g_warning("%s: %s", path, e->message);
g_error_free(e);
}
// TODO(p): Possibly add thumbnail images as well.
load_libheif_aux_images(path, handle, &result, &result_tail);
heif_image_handle_release(handle);
}
if (!result) {
g_clear_pointer(&result, cairo_surface_destroy);
set_error(error, "empty or unsupported image");
}
g_free(ids);
fail_read:
heif_context_free(ctx);
return fiv_io_profile_finalize(result, profile);
}
#endif // HAVE_LIBHEIF --------------------------------------------------------
#ifdef HAVE_LIBTIFF //---------------------------------------------------------
struct fiv_io_tiff {
unsigned char *data;
gchar *error;
// No, libtiff, the offset is not supposed to be unsigned (also see:
// man 0p sys_types.h), but at least it's fewer cases for us to care about.
toff_t position, len;
};
static tsize_t
fiv_io_tiff_read(thandle_t h, tdata_t buf, tsize_t len)
{
struct fiv_io_tiff *io = h;
if (len < 0) {
// What the FUCK! This argument is not supposed to be signed!
// How many mistakes can you make in such a basic API?
errno = EOWNERDEAD;
return -1;
}
if (io->position > io->len) {
errno = EOVERFLOW;
return -1;
}
toff_t n = MIN(io->len - io->position, (toff_t) len);
if (n > TIFF_TMSIZE_T_MAX) {
errno = EIO;
return -1;
}
memcpy(buf, io->data + io->position, n);
io->position += n;
return n;
}
static tsize_t
fiv_io_tiff_write(G_GNUC_UNUSED thandle_t h,
G_GNUC_UNUSED tdata_t buf, G_GNUC_UNUSED tsize_t len)
{
errno = EBADF;
return -1;
}
static toff_t
fiv_io_tiff_seek(thandle_t h, toff_t offset, int whence)
{
struct fiv_io_tiff *io = h;
switch (whence) {
case SEEK_SET:
io->position = offset;
break;
case SEEK_CUR:
io->position += offset;
break;
case SEEK_END:
io->position = io->len + offset;
break;
default:
errno = EINVAL;
return -1;
}
return io->position;
}
static int
fiv_io_tiff_close(G_GNUC_UNUSED thandle_t h)
{
return 0;
}
static toff_t
fiv_io_tiff_size(thandle_t h)
{
return ((struct fiv_io_tiff *) h)->len;
}
static void
fiv_io_tiff_error(
thandle_t h, const char *module, const char *format, va_list ap)
{
struct fiv_io_tiff *io = h;
gchar *message = g_strdup_vprintf(format, ap);
if (io->error)
// I'm not sure if two errors can ever come in a succession,
// but make sure to log them in any case.
g_warning("tiff: %s: %s", module, message);
else
io->error = g_strconcat(module, ": ", message, NULL);
g_free(message);
}
static void
fiv_io_tiff_warning(G_GNUC_UNUSED thandle_t h,
const char *module, const char *format, va_list ap)
{
gchar *message = g_strdup_vprintf(format, ap);
g_debug("tiff: %s: %s", module, message);
g_free(message);
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
static cairo_surface_t *
load_libtiff_directory(TIFF *tiff, GError **error)
{
char emsg[1024] = "";
if (!TIFFRGBAImageOK(tiff, emsg)) {
set_error(error, emsg);
return NULL;
}
// TODO(p): Are there cases where we might not want to "stop on error"?
TIFFRGBAImage image;
if (!TIFFRGBAImageBegin(&image, tiff, 1 /* stop on error */, emsg)) {
set_error(error, emsg);
return NULL;
}
cairo_surface_t *surface = NULL;
if (image.width > G_MAXINT || image.height >= G_MAXINT ||
G_MAXUINT32 / image.width < image.height) {
set_error(error, "image dimensions too large");
goto fail;
}
surface = cairo_image_surface_create(
CAIRO_FORMAT_ARGB32, image.width, image.height);
image.req_orientation = ORIENTATION_LEFTTOP;
uint32_t *raster = (uint32_t *) cairo_image_surface_get_data(surface);
if (!TIFFRGBAImageGet(&image, raster, image.width, image.height)) {
g_clear_pointer(&surface, cairo_surface_destroy);
goto fail;
}
// Needs to be converted from ABGR to alpha-premultiplied ARGB for Cairo.
for (uint32_t i = image.width * image.height; i--;) {
uint32_t pixel = raster[i],
a = TIFFGetA(pixel),
b = TIFFGetB(pixel) * a / 255,
g = TIFFGetG(pixel) * a / 255,
r = TIFFGetR(pixel) * a / 255;
raster[i] = a << 24 | r << 16 | g << 8 | b;
}
cairo_surface_mark_dirty(surface);
// XXX: The whole file is essentially an Exif, any ideas?
const uint32_t meta_len = 0;
const void *meta = NULL;
if (TIFFGetField(tiff, TIFFTAG_ICCPROFILE, &meta_len, &meta)) {
cairo_surface_set_user_data(surface, &fiv_io_key_icc,
g_bytes_new(meta, meta_len), (cairo_destroy_func_t) g_bytes_unref);
}
if (TIFFGetField(tiff, TIFFTAG_XMLPACKET, &meta_len, &meta)) {
cairo_surface_set_user_data(surface, &fiv_io_key_xmp,
g_bytes_new(meta, meta_len), (cairo_destroy_func_t) g_bytes_unref);
}
// Don't ask. The API is high, alright, I'm just not sure about the level.
uint16_t orientation = 0;
if (TIFFGetField(tiff, TIFFTAG_ORIENTATION, &orientation)) {
if (orientation == 5 || orientation == 7)
cairo_surface_set_user_data(
surface, &fiv_io_key_orientation, (void *) (uintptr_t) 5, NULL);
if (orientation == 6 || orientation == 8)
cairo_surface_set_user_data(
surface, &fiv_io_key_orientation, (void *) (uintptr_t) 7, NULL);
}
fail:
TIFFRGBAImageEnd(&image);
// TODO(p): It's possible to implement ClipPath easily with Cairo.
return surface;
}
static cairo_surface_t *
open_libtiff(const gchar *data, gsize len, const gchar *path, GError **error)
{
// Both kinds of handlers are called, redirect everything.
TIFFErrorHandler eh = TIFFSetErrorHandler(NULL);
TIFFErrorHandler wh = TIFFSetWarningHandler(NULL);
TIFFErrorHandlerExt ehe = TIFFSetErrorHandlerExt(fiv_io_tiff_error);
TIFFErrorHandlerExt whe = TIFFSetWarningHandlerExt(fiv_io_tiff_warning);
struct fiv_io_tiff h = {
.data = (unsigned char *) data,
.position = 0,
.len = len,
};
cairo_surface_t *result = NULL, *result_tail = NULL;
TIFF *tiff = TIFFClientOpen(path, "rm" /* Avoid mmap. */, &h,
fiv_io_tiff_read, fiv_io_tiff_write, fiv_io_tiff_seek,
fiv_io_tiff_close, fiv_io_tiff_size, NULL, NULL);
if (!tiff)
goto fail;
// In Nikon NEF files, IFD0 is a tiny uncompressed thumbnail with SubIFDs--
// two of them JPEGs, the remaining one is raw. libtiff cannot read either
// of those better versions.
//
// TODO(p): If NewSubfileType is ReducedImage, and it has SubIFDs compressed
// as old JPEG (6), decode JPEGInterchangeFormat/JPEGInterchangeFormatLength
// with libjpeg-turbo and insert them as the starting pages.
//
// This is not possible with libtiff directly, because TIFFSetSubDirectory()
// requires an ImageLength tag that's missing, and TIFFReadCustomDirectory()
// takes a privately defined struct that cannot be omitted.
//
// TODO(p): Samsung Android DNGs also claim to be TIFF/EP, but use a smaller
// uncompressed YCbCr image. Apple ProRAW uses the new JPEG Compression (7),
// with a weird Orientation. It also uses that value for its raw data.
uint32_t subtype = 0;
uint16_t subifd_count = 0;
const uint64_t *subifd_offsets = NULL;
if (TIFFGetField(tiff, TIFFTAG_SUBFILETYPE, &subtype) &&
(subtype & FILETYPE_REDUCEDIMAGE) &&
TIFFGetField(tiff, TIFFTAG_SUBIFD, &subifd_count, &subifd_offsets) &&
subifd_count > 0 && subifd_offsets) {
}
do {
// We inform about unsupported directories, but do not fail on them.
GError *err = NULL;
if (!try_append_page(
load_libtiff_directory(tiff, &err), &result, &result_tail)) {
g_warning("%s: %s", path, err->message);
g_error_free(err);
}
} while (TIFFReadDirectory(tiff));
TIFFClose(tiff);
fail:
if (h.error) {
g_clear_pointer(&result, cairo_surface_destroy);
set_error(error, h.error);
g_free(h.error);
} else if (!result) {
set_error(error, "empty or unsupported image");
}
TIFFSetErrorHandlerExt(ehe);
TIFFSetWarningHandlerExt(whe);
TIFFSetErrorHandler(eh);
TIFFSetWarningHandler(wh);
return result;
}
#endif // HAVE_LIBTIFF --------------------------------------------------------
#ifdef HAVE_GDKPIXBUF // ------------------------------------------------------
static cairo_surface_t *
open_gdkpixbuf(
const gchar *data, gsize len, FivIoProfile profile, GError **error)
{
// gdk-pixbuf controls the playback itself, there is no reliable method of
// extracting individual frames (due to loops).
GInputStream *is = g_memory_input_stream_new_from_data(data, len, NULL);
GdkPixbuf *pixbuf = gdk_pixbuf_new_from_stream(is, NULL, error);
g_object_unref(is);
if (!pixbuf)
return NULL;
cairo_surface_t *surface =
gdk_cairo_surface_create_from_pixbuf(pixbuf, 1, NULL);
const char *orientation = gdk_pixbuf_get_option(pixbuf, "orientation");
if (orientation && strlen(orientation) == 1) {
int n = *orientation - '0';
if (n >= 1 && n <= 8)
cairo_surface_set_user_data(
surface, &fiv_io_key_orientation, (void *) (uintptr_t) n, NULL);
}
const char *icc_profile = gdk_pixbuf_get_option(pixbuf, "icc-profile");
if (icc_profile) {
gsize out_len = 0;
guchar *raw = g_base64_decode(icc_profile, &out_len);
if (raw) {
cairo_surface_set_user_data(surface, &fiv_io_key_icc,
g_bytes_new_take(raw, out_len),
(cairo_destroy_func_t) g_bytes_unref);
}
}
g_object_unref(pixbuf);
return fiv_io_profile_finalize(surface, profile);
}
#endif // HAVE_GDKPIXBUF ------------------------------------------------------
cairo_user_data_key_t fiv_io_key_exif;
cairo_user_data_key_t fiv_io_key_orientation;
cairo_user_data_key_t fiv_io_key_icc;
cairo_user_data_key_t fiv_io_key_xmp;
cairo_user_data_key_t fiv_io_key_frame_next;
cairo_user_data_key_t fiv_io_key_frame_previous;
cairo_user_data_key_t fiv_io_key_frame_duration;
cairo_user_data_key_t fiv_io_key_loops;
cairo_user_data_key_t fiv_io_key_page_next;
cairo_user_data_key_t fiv_io_key_page_previous;
cairo_surface_t *
fiv_io_open(
const gchar *path, FivIoProfile profile, gboolean enhance, GError **error)
{
// TODO(p): Don't always load everything into memory, test type first,
// so that we can reject non-pictures early. Wuffs only needs the first
// 16 bytes (soon 12) to make a guess right now.
//
// LibRaw poses an issue--there is no good registry for identification
// of supported files. Many of them are compliant TIFF files.
// The only good filtering method for RAWs are currently file extensions
// extracted from shared-mime-info.
//
// SVG is also problematic, an unbounded search for its root element.
// But problematic files can be assumed to be crafted.
//
// gdk-pixbuf exposes its detection data through gdk_pixbuf_get_formats().
// This may also be unbounded, as per format_check().
gchar *data = NULL;
gsize len = 0;
if (!g_file_get_contents(path, &data, &len, error))
return NULL;
cairo_surface_t *surface =
fiv_io_open_from_data(data, len, path, profile, enhance, error);
free(data);
return surface;
}
cairo_surface_t *
fiv_io_open_from_data(const char *data, size_t len, const gchar *path,
FivIoProfile profile, gboolean enhance, GError **error)
{
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 so far unsupported here.
surface = open_wuffs_using(
wuffs_bmp__decoder__alloc_as__wuffs_base__image_decoder, data, len,
profile, error);
break;
case WUFFS_BASE__FOURCC__GIF:
surface = open_wuffs_using(
wuffs_gif__decoder__alloc_as__wuffs_base__image_decoder, data, len,
profile, error);
break;
case WUFFS_BASE__FOURCC__PNG:
surface = open_wuffs_using(
wuffs_png__decoder__alloc_as__wuffs_base__image_decoder, data, len,
profile, error);
break;
case WUFFS_BASE__FOURCC__JPEG:
surface = enhance
? open_libjpeg_enhanced(data, len, profile, error)
: open_libjpeg_turbo(data, len, profile, 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.
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_LIBRAW ---------------------------------------------------------
#ifdef HAVE_LIBRSVG // --------------------------------------------------------
if ((surface = open_librsvg(data, len, path, error)))
break;
// XXX: It doesn't look like librsvg can return sensible errors.
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_LIBRSVG --------------------------------------------------------
#ifdef HAVE_XCURSOR //---------------------------------------------------------
if ((surface = open_xcursor(data, len, error)))
break;
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_XCURSOR --------------------------------------------------------
#ifdef HAVE_LIBWEBP //---------------------------------------------------------
// TODO(p): https://github.com/google/wuffs/commit/4c04ac1
if ((surface = open_libwebp(data, len, path, profile, error)))
break;
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_LIBWEBP --------------------------------------------------------
#ifdef HAVE_LIBHEIF //---------------------------------------------------------
if ((surface = open_libheif(data, len, path, profile, error)))
break;
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_LIBHEIF --------------------------------------------------------
#ifdef HAVE_LIBTIFF //---------------------------------------------------------
// This needs to be positioned after LibRaw.
if ((surface = open_libtiff(data, len, path, error)))
break;
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_LIBTIFF --------------------------------------------------------
#ifdef HAVE_GDKPIXBUF // ------------------------------------------------------
// This is only used as a last resort, the rest above is special-cased.
if ((surface = open_gdkpixbuf(data, len, profile, error)))
break;
if (error && (*error)->code != GDK_PIXBUF_ERROR_UNKNOWN_TYPE)
break;
if (error) {
g_debug("%s", (*error)->message);
g_clear_error(error);
}
#endif // HAVE_GDKPIXBUF ------------------------------------------------------
set_error(error, "unsupported file type");
}
// gdk-pixbuf only gives out this single field--cater to its limitations,
// since we'd really like to have it.
// TODO(p): The Exif orientation should be ignored in JPEG-XL at minimum.
GBytes *exif = NULL;
gsize exif_len = 0;
gconstpointer exif_data = NULL;
if (surface &&
(exif = cairo_surface_get_user_data(surface, &fiv_io_key_exif)) &&
(exif_data = g_bytes_get_data(exif, &exif_len))) {
cairo_surface_set_user_data(surface, &fiv_io_key_orientation,
(void *) (uintptr_t) fiv_io_exif_orientation(exif_data, exif_len),
NULL);
}
return surface;
}
// --- Export ------------------------------------------------------------------
#ifdef HAVE_LIBWEBP
static WebPData
encode_lossless_webp(cairo_surface_t *surface)
{
cairo_format_t format = cairo_image_surface_get_format(surface);
int w = cairo_image_surface_get_width(surface);
int h = cairo_image_surface_get_height(surface);
if (format != CAIRO_FORMAT_ARGB32 &&
format != CAIRO_FORMAT_RGB24) {
cairo_surface_t *converted =
cairo_image_surface_create((format = CAIRO_FORMAT_ARGB32), w, h);
cairo_t *cr = cairo_create(converted);
cairo_set_source_surface(cr, surface, 0, 0);
cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
cairo_paint(cr);
cairo_destroy(cr);
surface = converted;
} else {
surface = cairo_surface_reference(surface);
}
WebPConfig config = {};
WebPPicture picture = {};
if (!WebPConfigInit(&config) ||
!WebPConfigLosslessPreset(&config, 6) ||
!WebPPictureInit(&picture))
goto fail;
config.thread_level = true;
if (!WebPValidateConfig(&config))
goto fail;
picture.use_argb = true;
picture.width = w;
picture.height = h;
if (!WebPPictureAlloc(&picture))
goto fail;
// Cairo uses a similar internal format, so we should be able to
// copy it over and fix up the minor differences.
// This is written to be easy to follow rather than fast.
int stride = cairo_image_surface_get_stride(surface);
if (picture.argb_stride != w ||
picture.argb_stride * (int) sizeof *picture.argb != stride ||
INT_MAX / picture.argb_stride < h)
goto fail_compatibility;
uint32_t *argb =
memcpy(picture.argb, cairo_image_surface_get_data(surface), stride * h);
if (format == CAIRO_FORMAT_ARGB32)
for (int i = h * picture.argb_stride; i-- > 0; argb++)
*argb = wuffs_base__color_u32_argb_premul__as__color_u32_argb_nonpremul(*argb);
else
for (int i = h * picture.argb_stride; i-- > 0; argb++)
*argb |= 0xFF000000;
WebPMemoryWriter writer = {};
WebPMemoryWriterInit(&writer);
picture.writer = WebPMemoryWrite;
picture.custom_ptr = &writer;
if (!WebPEncode(&config, &picture))
g_debug("WebPEncode: %d\n", picture.error_code);
fail_compatibility:
WebPPictureFree(&picture);
fail:
cairo_surface_destroy(surface);
return (WebPData) {.bytes = writer.mem, .size = writer.size};
}
static gboolean
encode_webp_image(WebPMux *mux, cairo_surface_t *frame)
{
WebPData bitstream = encode_lossless_webp(frame);
gboolean ok = WebPMuxSetImage(mux, &bitstream, true) == WEBP_MUX_OK;
WebPDataClear(&bitstream);
return ok;
}
static gboolean
encode_webp_animation(WebPMux *mux, cairo_surface_t *page)
{
gboolean ok = TRUE;
for (cairo_surface_t *frame = page; ok && frame; frame =
cairo_surface_get_user_data(frame, &fiv_io_key_frame_next)) {
WebPMuxFrameInfo info = {
.bitstream = encode_lossless_webp(frame),
.duration = (intptr_t) cairo_surface_get_user_data(
frame, &fiv_io_key_frame_duration),
.id = WEBP_CHUNK_ANMF,
.dispose_method = WEBP_MUX_DISPOSE_NONE,
.blend_method = WEBP_MUX_NO_BLEND,
};
ok = WebPMuxPushFrame(mux, &info, true) == WEBP_MUX_OK;
WebPDataClear(&info.bitstream);
}
WebPMuxAnimParams params = {
.bgcolor = 0x00000000, // BGRA, curiously.
.loop_count = (uintptr_t)
cairo_surface_get_user_data(page, &fiv_io_key_loops),
};
return ok && WebPMuxSetAnimationParams(mux, ¶ms) == WEBP_MUX_OK;
}
static gboolean
transfer_metadata(WebPMux *mux, const char *fourcc, cairo_surface_t *page,
const cairo_user_data_key_t *kind)
{
GBytes *data = cairo_surface_get_user_data(page, kind);
if (!data)
return TRUE;
gsize len = 0;
gconstpointer p = g_bytes_get_data(data, &len);
return WebPMuxSetChunk(mux, fourcc, &(WebPData) {.bytes = p, .size = len},
false) == WEBP_MUX_OK;
}
gboolean
fiv_io_save(cairo_surface_t *page, cairo_surface_t *frame, const gchar *path,
GError **error)
{
g_return_val_if_fail(page != NULL, FALSE);
g_return_val_if_fail(path != NULL, FALSE);
gboolean ok = TRUE;
WebPMux *mux = WebPMuxNew();
if (frame)
ok = encode_webp_image(mux, frame);
else if (!cairo_surface_get_user_data(page, &fiv_io_key_frame_next))
ok = encode_webp_image(mux, page);
else
ok = encode_webp_animation(mux, page);
ok = ok && transfer_metadata(mux, "EXIF", page, &fiv_io_key_exif);
ok = ok && transfer_metadata(mux, "ICCP", page, &fiv_io_key_icc);
ok = ok && transfer_metadata(mux, "XMP ", page, &fiv_io_key_xmp);
WebPData assembled = {};
WebPDataInit(&assembled);
if (!(ok = ok && WebPMuxAssemble(mux, &assembled) == WEBP_MUX_OK))
set_error(error, "encoding failed");
else
ok = g_file_set_contents(
path, (const gchar *) assembled.bytes, assembled.size, error);
WebPMuxDelete(mux);
WebPDataClear(&assembled);
return ok;
}
#endif // HAVE_LIBWEBP
// --- Metadata ----------------------------------------------------------------
FivIoOrientation
fiv_io_exif_orientation(const guint8 *tiff, gsize len)
{
// libtiff also knows how to do this, but it's not a lot of code.
// The "Orientation" tag/field is part of Baseline TIFF 6.0 (1992),
// it just so happens that Exif is derived from this format.
// There is no other meaningful placement for this than right in IFD0,
// describing the main image.
const uint8_t *end = tiff + len,
le[4] = {'I', 'I', 42, 0},
be[4] = {'M', 'M', 0, 42};
uint16_t (*u16)(const uint8_t *) = NULL;
uint32_t (*u32)(const uint8_t *) = NULL;
if (tiff + 8 > end) {
return FivIoOrientationUnknown;
} else if (!memcmp(tiff, le, sizeof le)) {
u16 = wuffs_base__peek_u16le__no_bounds_check;
u32 = wuffs_base__peek_u32le__no_bounds_check;
} else if (!memcmp(tiff, be, sizeof be)) {
u16 = wuffs_base__peek_u16be__no_bounds_check;
u32 = wuffs_base__peek_u32be__no_bounds_check;
} else {
return FivIoOrientationUnknown;
}
const uint8_t *ifd0 = tiff + u32(tiff + 4);
if (ifd0 + 2 > end)
return FivIoOrientationUnknown;
uint16_t fields = u16(ifd0);
enum { BYTE = 1, ASCII, SHORT, LONG, RATIONAL,
SBYTE, UNDEFINED, SSHORT, SLONG, SRATIONAL, FLOAT, DOUBLE };
enum { Orientation = 274 };
for (const guint8 *p = ifd0 + 2; fields-- && p + 12 <= end; p += 12) {
uint16_t tag = u16(p), type = u16(p + 2), value16 = u16(p + 8);
uint32_t count = u32(p + 4);
if (tag == Orientation && type == SHORT && count == 1 &&
value16 >= 1 && value16 <= 8)
return value16;
}
return FivIoOrientationUnknown;
}
gboolean
fiv_io_save_metadata(cairo_surface_t *page, const gchar *path, GError **error)
{
g_return_val_if_fail(page != NULL, FALSE);
FILE *fp = fopen(path, "wb");
if (!fp) {
g_set_error(error, G_IO_ERROR, g_io_error_from_errno(errno),
"%s: %s", path, g_strerror(errno));
return FALSE;
}
// This does not constitute a valid JPEG codestream--it's a TEM marker
// (standalone) with trailing nonsense.
fprintf(fp, "\xFF\001Exiv2");
GBytes *data = NULL;
gsize len = 0;
gconstpointer p = NULL;
// Adobe XMP Specification Part 3: Storage in Files, 2020/1, 1.1.3
// I don't care if Exiv2 supports it this way.
if ((data = cairo_surface_get_user_data(page, &fiv_io_key_exif)) &&
(p = g_bytes_get_data(data, &len))) {
while (len) {
gsize chunk = MIN(len, 0xFFFF - 2 - 6);
uint8_t header[10] = "\xFF\xE1\000\000Exif\000\000";
header[2] = (chunk + 2 + 6) >> 8;
header[3] = (chunk + 2 + 6);
fwrite(header, 1, sizeof header, fp);
fwrite(p, 1, chunk, fp);
len -= chunk;
p += chunk;
}
}
// https://www.color.org/specification/ICC1v43_2010-12.pdf B.4
if ((data = cairo_surface_get_user_data(page, &fiv_io_key_icc)) &&
(p = g_bytes_get_data(data, &len))) {
gsize limit = 0xFFFF - 2 - 12;
uint8_t current = 0, total = (len + limit - 1) / limit;
while (len) {
gsize chunk = MIN(len, limit);
uint8_t header[18] = "\xFF\xE2\000\000ICC_PROFILE\000\000\000";
header[2] = (chunk + 2 + 12 + 2) >> 8;
header[3] = (chunk + 2 + 12 + 2);
header[16] = ++current;
header[17] = total;
fwrite(header, 1, sizeof header, fp);
fwrite(p, 1, chunk, fp);
len -= chunk;
p += chunk;
}
}
// Adobe XMP Specification Part 3: Storage in Files, 2020/1, 1.1.3
// If the main segment overflows, then it's a sign of bad luck,
// because 1.1.3.1 is way too complex.
if ((data = cairo_surface_get_user_data(page, &fiv_io_key_xmp)) &&
(p = g_bytes_get_data(data, &len))) {
while (len) {
gsize chunk = MIN(len, 0xFFFF - 2 - 29);
uint8_t header[33] =
"\xFF\xE1\000\000http://ns.adobe.com/xap/1.0/\000";
header[2] = (chunk + 2 + 29) >> 8;
header[3] = (chunk + 2 + 29);
fwrite(header, 1, sizeof header, fp);
fwrite(p, 1, chunk, fp);
break;
}
}
fprintf(fp, "\xFF\xD9");
if (ferror(fp)) {
g_set_error(error, G_IO_ERROR, g_io_error_from_errno(errno),
"%s: %s", path, g_strerror(errno));
fclose(fp);
return FALSE;
}
if (fclose(fp)) {
g_set_error(error, G_IO_ERROR, g_io_error_from_errno(errno),
"%s: %s", path, g_strerror(errno));
return FALSE;
}
return TRUE;
}
// --- Thumbnails --------------------------------------------------------------
GType
fiv_io_thumbnail_size_get_type(void)
{
static gsize guard;
if (g_once_init_enter(&guard)) {
#define XX(name, value, dir) {FIV_IO_THUMBNAIL_SIZE_ ## name, \
"FIV_IO_THUMBNAIL_SIZE_" #name, #name},
static const GEnumValue values[] = {FIV_IO_THUMBNAIL_SIZES(XX) {}};
#undef XX
GType type = g_enum_register_static(
g_intern_static_string("FivIoThumbnailSize"), values);
g_once_init_leave(&guard, type);
}
return guard;
}
#define XX(name, value, dir) {value, dir},
FivIoThumbnailSizeInfo
fiv_io_thumbnail_sizes[FIV_IO_THUMBNAIL_SIZE_COUNT] = {
FIV_IO_THUMBNAIL_SIZES(XX)};
#undef XX
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#ifndef __linux__
#define st_mtim st_mtimespec
#endif // ! __linux__
static int // tri-state
check_spng_thumbnail_texts(struct spng_text *texts, uint32_t texts_len,
const gchar *target, time_t mtime)
{
// May contain Thumb::Image::Width Thumb::Image::Height,
// but those aren't interesting currently (would be for fast previews).
bool need_uri = true, need_mtime = true;
for (uint32_t i = 0; i < texts_len; i++) {
struct spng_text *text = texts + i;
if (!strcmp(text->keyword, "Thumb::URI")) {
need_uri = false;
if (strcmp(target, text->text))
return false;
}
if (!strcmp(text->keyword, "Thumb::MTime")) {
need_mtime = false;
if (atol(text->text) != mtime)
return false;
}
}
return need_uri || need_mtime ? -1 : true;
}
static int // tri-state
check_spng_thumbnail(spng_ctx *ctx, const gchar *target, time_t mtime, int *err)
{
uint32_t texts_len = 0;
if ((*err = spng_get_text(ctx, NULL, &texts_len)))
return false;
int result = false;
struct spng_text *texts = g_malloc0_n(texts_len, sizeof *texts);
if (!(*err = spng_get_text(ctx, texts, &texts_len)))
result = check_spng_thumbnail_texts(texts, texts_len, target, mtime);
g_free(texts);
return result;
}
static cairo_surface_t *
read_spng_thumbnail(
const gchar *path, const gchar *uri, time_t mtime, GError **error)
{
FILE *fp;
cairo_surface_t *result = NULL;
if (!(fp = fopen(path, "rb"))) {
set_error(error, g_strerror(errno));
return NULL;
}
errno = 0;
spng_ctx *ctx = spng_ctx_new(0);
if (!ctx) {
set_error(error, g_strerror(errno));
goto fail_init;
}
int err;
size_t size = 0;
if ((err = spng_set_png_file(ctx, fp)) ||
(err = spng_set_image_limits(ctx, INT16_MAX, INT16_MAX)) ||
(err = spng_decoded_image_size(ctx, SPNG_FMT_RGBA8, &size))) {
set_error(error, spng_strerror(err));
goto fail;
}
if (check_spng_thumbnail(ctx, uri, mtime, &err) == false) {
set_error(error, err ? spng_strerror(err) : "mismatch");
goto fail;
}
struct spng_ihdr ihdr = {};
struct spng_trns trns = {};
spng_get_ihdr(ctx, &ihdr);
bool may_be_translucent = !spng_get_trns(ctx, &trns) ||
ihdr.color_type == SPNG_COLOR_TYPE_GRAYSCALE_ALPHA ||
ihdr.color_type == SPNG_COLOR_TYPE_TRUECOLOR_ALPHA;
cairo_surface_t *surface = cairo_image_surface_create(
may_be_translucent ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24,
ihdr.width, ihdr.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));
goto fail_data;
}
uint32_t *data = (uint32_t *) cairo_image_surface_get_data(surface);
g_assert((size_t) cairo_image_surface_get_stride(surface) *
cairo_image_surface_get_height(surface) == size);
cairo_surface_flush(surface);
if ((err = spng_decode_image(ctx, data, size, SPNG_FMT_RGBA8,
SPNG_DECODE_TRNS | SPNG_DECODE_GAMMA))) {
set_error(error, spng_strerror(err));
goto fail_data;
}
// The specification does not say where the required metadata should be,
// it could very well be broken up into two parts.
if (check_spng_thumbnail(ctx, uri, mtime, &err) != true) {
set_error(
error, err ? spng_strerror(err) : "mismatch or not a thumbnail");
goto fail_data;
}
// pixman can be mildly abused to do this operation, but it won't be faster.
if (may_be_translucent) {
for (size_t i = size / sizeof *data; i--; ) {
const uint8_t *unit = (const uint8_t *) &data[i];
uint32_t a = unit[3],
b = PREMULTIPLY8(a, unit[2]),
g = PREMULTIPLY8(a, unit[1]),
r = PREMULTIPLY8(a, unit[0]);
data[i] = a << 24 | r << 16 | g << 8 | b;
}
} else {
for (size_t i = size / sizeof *data; i--; ) {
uint32_t rgba = g_ntohl(data[i]);
data[i] = rgba << 24 | rgba >> 8;
}
}
cairo_surface_mark_dirty((result = surface));
fail_data:
if (!result)
cairo_surface_destroy(surface);
fail:
spng_ctx_free(ctx);
fail_init:
fclose(fp);
return result;
}
cairo_surface_t *
fiv_io_lookup_thumbnail(GFile *target, FivIoThumbnailSize size)
{
g_return_val_if_fail(size >= FIV_IO_THUMBNAIL_SIZE_MIN &&
size <= FIV_IO_THUMBNAIL_SIZE_MAX, NULL);
// Local files only, at least for now.
gchar *path = g_file_get_path(target);
if (!path)
return NULL;
GStatBuf st = {};
int err = g_stat(path, &st);
g_free(path);
if (err)
return NULL;
gchar *uri = g_file_get_uri(target);
gchar *sum = g_compute_checksum_for_string(G_CHECKSUM_MD5, uri, -1);
gchar *cache_dir = get_xdg_home_dir("XDG_CACHE_HOME", ".cache");
// The lookup sequence is: nominal..max, then mirroring back to ..min.
cairo_surface_t *result = NULL;
GError *error = NULL;
for (int i = 0; i < FIV_IO_THUMBNAIL_SIZE_COUNT; i++) {
int use = size + i;
if (use > FIV_IO_THUMBNAIL_SIZE_MAX)
use = FIV_IO_THUMBNAIL_SIZE_MAX - i;
gchar *path = g_strdup_printf("%s/thumbnails/%s/%s.png", cache_dir,
fiv_io_thumbnail_sizes[use].thumbnail_spec_name, sum);
result = read_spng_thumbnail(path, uri, st.st_mtim.tv_sec, &error);
if (error) {
g_debug("%s: %s", path, error->message);
g_clear_error(&error);
}
g_free(path);
if (result)
break;
}
g_free(cache_dir);
g_free(sum);
g_free(uri);
return result;
}
int
fiv_io_filecmp(GFile *location1, GFile *location2)
{
if (g_file_has_prefix(location1, location2))
return +1;
if (g_file_has_prefix(location2, location1))
return -1;
gchar *name1 = g_file_get_parse_name(location1);
gchar *name2 = g_file_get_parse_name(location2);
int result = g_utf8_collate(name1, name2);
g_free(name1);
g_free(name2);
return result;
}