Ladybird/ladybird
1
0
Fork 0
mirror of https://github.com/LadybirdBrowser/ladybird.git synced 2025-06-09 17:44:56 +09:00
Code Activity

LibGfx: Add .cur file support to ICO loader

Browse source 
This extends ICO loader to support Windows cursor files. There is no
point in creating a separate loader for this, as the ICO format is
very similar to the CUR format. The only differences are bytes used to
identify the file and a presence of a hotspot in the CUR header.
This commit is contained in:
aplefull 2025-05-06 17:49:14 +02:00 • committed by Jelle Raaijmakers
parent 48ca895f5f
commit 4d8717fa3a
Notes: github-actions[bot] 2025-05-09 19:49:29 +00:00
3 changed files with 48 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

46
Libraries/LibGfx/ImageFormats/ICOLoader.cpp
View file

@ -13,10 +13,15 @@
namespace Gfx {
enum class IconType : u16 {
ICO = 1,
CUR = 2,
};
// FIXME: This is in little-endian order. Maybe need a NetworkOrdered<T> equivalent eventually.
struct ICONDIR {
u16 must_be_0 = 0;
u16 must_be_1 = 0;
IconType type = IconType::ICO;
u16 image_count = 0;
};
static_assert(AssertSize<ICONDIR, 6>());
@ -53,6 +58,8 @@ struct ICOImageDescriptor {
u16 width;
u16 height;
u16 bits_per_pixel;
u16 hotspot_x { 0 };
u16 hotspot_y { 0 };
size_t offset;
size_t size;
RefPtr<Gfx::Bitmap> bitmap;
@ -68,22 +75,40 @@ struct ICOLoadingContext {
State state { NotDecoded };
u8 const* data { nullptr };
size_t data_size { 0 };
IconType file_type { IconType::ICO };
Vector<ICOImageDescriptor> images;
size_t largest_index;
};
static ErrorOr<size_t> decode_ico_header(Stream& stream)
static ErrorOr<size_t> decode_ico_header(Stream& stream, IconType& out_type)
{
auto header = TRY(stream.read_value<ICONDIR>());
if (header.must_be_0 != 0 || header.must_be_1 != 1)
return Error::from_string_literal("Invalid ICO header");
if (header.must_be_0 != 0 || (header.type != IconType::ICO && header.type != IconType::CUR))
return Error::from_string_literal("Invalid ICO/CUR header");
out_type = header.type;
return { header.image_count };
}
static ErrorOr<ICOImageDescriptor> decode_ico_direntry(Stream& stream)
static ErrorOr<ICOImageDescriptor> decode_ico_direntry(Stream& stream, IconType file_type)
{
auto entry = TRY(stream.read_value<ICONDIRENTRY>());
ICOImageDescriptor desc = { entry.width, entry.height, entry.bits_per_pixel, entry.offset, entry.size, nullptr };
ICOImageDescriptor desc = {
entry.width,
entry.height,
entry.bits_per_pixel,
0, 0,
entry.offset,
entry.size,
nullptr
};
if (file_type == IconType::CUR) {
// For cursor files, hotsport coordinates are stored in the planes and bits_per_pixel fields
desc.hotspot_x = entry.planes;
desc.hotspot_y = entry.bits_per_pixel;
}
if (desc.width == 0)
desc.width = 256;
if (desc.height == 0)
@ -115,12 +140,12 @@ static ErrorOr<void> load_ico_directory(ICOLoadingContext& context)
{
FixedMemoryStream stream { { context.data, context.data_size } };
auto image_count = TRY(decode_ico_header(stream));
auto image_count = TRY(decode_ico_header(stream, context.file_type));
if (image_count == 0)
return Error::from_string_literal("ICO file has no images");
return Error::from_string_literal("ICO/CUR file has no images");
for (size_t i = 0; i < image_count; ++i) {
auto desc = TRY(decode_ico_direntry(stream));
auto desc = TRY(decode_ico_direntry(stream, context.file_type));
if (desc.offset + desc.size < desc.offset // detect integer overflow
|| (desc.offset + desc.size) > context.data_size) {
dbgln_if(ICO_DEBUG, "load_ico_directory: offset: {} size: {} doesn't fit in ICO size: {}", desc.offset, desc.size, context.data_size);
@ -175,7 +200,8 @@ ErrorOr<void> ICOImageDecoderPlugin::load_ico_bitmap(ICOLoadingContext& context)
bool ICOImageDecoderPlugin::sniff(ReadonlyBytes data)
{
FixedMemoryStream stream { data };
return !decode_ico_header(stream).is_error();
IconType file_type;
return !decode_ico_header(stream, file_type).is_error();
}
ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> ICOImageDecoderPlugin::create(ReadonlyBytes data)