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LibGfx+GIFLoader: Use InputMemoryStream instead of BufferStream.

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asynts 2020-09-19 19:18:21 +02:00 • committed by Andreas Kling
parent 5056d8bb20
commit 0f5b42ac80
1 changed files with 46 additions and 33 deletions
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79
Libraries/LibGfx/GIFLoader.cpp
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@ -24,10 +24,11 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/ */
#include <AK/BufferStream.h> #include <AK/Array.h>
#include <AK/ByteBuffer.h> #include <AK/ByteBuffer.h>
#include <AK/LexicalPath.h> #include <AK/LexicalPath.h>
#include <AK/MappedFile.h> #include <AK/MappedFile.h>
#include <AK/MemoryStream.h>
#include <AK/NonnullOwnPtrVector.h> #include <AK/NonnullOwnPtrVector.h>
#include <LibGfx/GIFLoader.h> #include <LibGfx/GIFLoader.h>
#include <LibGfx/Painter.h> #include <LibGfx/Painter.h>
@ -122,21 +123,20 @@ enum class GIFFormat {
GIF89a, GIF89a,
}; };
static Optional<GIFFormat> decode_gif_header(BufferStream& stream) static Optional<GIFFormat> decode_gif_header(InputMemoryStream& stream)
{ {
static const char valid_header_87[] = "GIF87a"; static const char valid_header_87[] = "GIF87a";
static const char valid_header_89[] = "GIF89a"; static const char valid_header_89[] = "GIF89a";
char header[6]; Array<u8, 6> header;
for (int i = 0; i < 6; ++i) stream >> header;
stream >> header[i];
if (stream.handle_read_failure()) if (stream.handle_any_error())
return {}; return {};
if (!memcmp(header, valid_header_87, sizeof(header))) if (header.span() == ReadonlyBytes { valid_header_87, 6 })
return GIFFormat::GIF87a; return GIFFormat::GIF87a;
else if (!memcmp(header, valid_header_89, sizeof(header))) if (header.span() == ReadonlyBytes { valid_header_89, 6 })
return GIFFormat::GIF89a; return GIFFormat::GIF89a;
return {}; return {};
@ -387,8 +387,7 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
if (context.data_size < 32) if (context.data_size < 32)
return false; return false;
auto buffer = ByteBuffer::wrap(const_cast<u8*>(context.data), context.data_size); InputMemoryStream stream { { context.data, context.data_size } };
BufferStream stream(buffer);
Optional<GIFFormat> format = decode_gif_header(stream); Optional<GIFFormat> format = decode_gif_header(stream);
if (!format.has_value()) { if (!format.has_value()) {
@ -397,15 +396,21 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
printf("Format is %s\n", format.value() == GIFFormat::GIF89a ? "GIF89a" : "GIF87a"); printf("Format is %s\n", format.value() == GIFFormat::GIF89a ? "GIF89a" : "GIF87a");
stream >> context.logical_screen.width; LittleEndian<u16> value;
stream >> context.logical_screen.height;
if (stream.handle_read_failure()) stream >> value;
context.logical_screen.width = value;
stream >> value;
context.logical_screen.height = value;
if (stream.handle_any_error())
return false; return false;
u8 gcm_info = 0; u8 gcm_info = 0;
stream >> gcm_info; stream >> gcm_info;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
bool global_color_map_follows_descriptor = gcm_info & 0x80; bool global_color_map_follows_descriptor = gcm_info & 0x80;
@ -418,14 +423,14 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
printf("bits_of_color_resolution: %u\n", bits_of_color_resolution); printf("bits_of_color_resolution: %u\n", bits_of_color_resolution);
stream >> context.background_color_index; stream >> context.background_color_index;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
printf("background_color: %u\n", context.background_color_index); printf("background_color: %u\n", context.background_color_index);
u8 pixel_aspect_ratio = 0; u8 pixel_aspect_ratio = 0;
stream >> pixel_aspect_ratio; stream >> pixel_aspect_ratio;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
int color_map_entry_count = 1; int color_map_entry_count = 1;
@ -442,7 +447,7 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
context.logical_screen.color_map[i] = { r, g, b }; context.logical_screen.color_map[i] = { r, g, b };
} }
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
for (int i = 0; i < color_map_entry_count; ++i) { for (int i = 0; i < color_map_entry_count; ++i) {
@ -459,7 +464,7 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
if (sentinel == 0x21) { if (sentinel == 0x21) {
u8 extension_type = 0; u8 extension_type = 0;
stream >> extension_type; stream >> extension_type;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
printf("Extension block of type %02x\n", extension_type); printf("Extension block of type %02x\n", extension_type);
@ -470,7 +475,7 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
for (;;) { for (;;) {
stream >> sub_block_length; stream >> sub_block_length;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
if (sub_block_length == 0) if (sub_block_length == 0)
@ -482,7 +487,7 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
sub_block.append(dummy); sub_block.append(dummy);
} }
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
} }
@ -529,13 +534,24 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
context.images.append(move(current_image)); context.images.append(move(current_image));
auto& image = context.images.last(); auto& image = context.images.last();
LittleEndian<u16> tmp;
u8 packed_fields { 0 }; u8 packed_fields { 0 };
stream >> image.x;
stream >> image.y; stream >> tmp;
stream >> image.width; image.x = tmp;
stream >> image.height;
stream >> tmp;
image.y = tmp;
stream >> tmp;
image.width = tmp;
stream >> tmp;
image.height = tmp;
stream >> packed_fields; stream >> packed_fields;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
image.use_global_color_map = !(packed_fields & 0x80); image.use_global_color_map = !(packed_fields & 0x80);
@ -564,18 +580,16 @@ static bool load_gif_frame_descriptors(GIFLoadingContext& context)
for (;;) { for (;;) {
stream >> lzw_encoded_bytes_expected; stream >> lzw_encoded_bytes_expected;
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
if (lzw_encoded_bytes_expected == 0) if (lzw_encoded_bytes_expected == 0)
break; break;
u8 buffer[256]; Array<u8, 256> buffer;
for (int i = 0; i < lzw_encoded_bytes_expected; ++i) { stream >> buffer.span().trim(lzw_encoded_bytes_expected);
stream >> buffer[i];
}
if (stream.handle_read_failure()) if (stream.handle_any_error())
return false; return false;
for (int i = 0; i < lzw_encoded_bytes_expected; ++i) { for (int i = 0; i < lzw_encoded_bytes_expected; ++i) {
@ -649,8 +663,7 @@ bool GIFImageDecoderPlugin::set_nonvolatile()
bool GIFImageDecoderPlugin::sniff() bool GIFImageDecoderPlugin::sniff()
{ {
auto buffer = ByteBuffer::wrap(const_cast<u8*>(m_context->data), m_context->data_size); InputMemoryStream stream { { m_context->data, m_context->data_size } };
BufferStream stream(buffer);
return decode_gif_header(stream).has_value(); return decode_gif_header(stream).has_value();
} }