void pngSetHeader(PngStream* stream)
{
stream->info.imageWidth = png_get_image_width(stream->png_ptr, stream->info_ptr);
stream->info.imageHeight = png_get_image_height(stream->png_ptr, stream->info_ptr);
stream->info.numComponents = png_get_channels(stream->png_ptr, stream->info_ptr);
stream->info.colorSpace = getPngDecColourType(png_get_color_type(stream->png_ptr, stream->info_ptr));
stream->info.bitDepth = png_get_bit_depth(stream->png_ptr, stream->info_ptr);
stream->info.interlaceMethod = png_get_interlace_type(stream->png_ptr, stream->info_ptr);
stream->info.chunkInformation = pngDecGetChunkInformation(stream);
}
s32 pngDecOpen(PPUThread& ppu, PHandle handle, PPStream png_stream, PSrc source, POpenInfo open_info, PCbControlStream control_stream = vm::null, POpenParam open_param = vm::null)
{
// Check if partial image decoding is used
if (control_stream || open_param)
{
throw EXCEPTION("Partial image decoding is not supported.");
}
// Allocate memory for the stream structure
auto stream = vm::ptr<PngStream>::make(handle->malloc(ppu, sizeof(PngStream), handle->malloc_arg).addr());
// Check if the allocation of memory for the stream structure failed
if (!stream)
{
cellPngDec.error("PNG stream creation failed.");
return CELL_PNGDEC_ERROR_FATAL;
}
// Set memory info
open_info->initSpaceAllocated = sizeof(PngStream);
// Set the stream source to the source give by the game
stream->source = *source;
// Indicate that a fixed alpha value isn't used, if not specified otherwise
stream->fixed_alpha = false;
// Use virtual memory address as a handle
*png_stream = stream;
// Allocate memory for the PNG buffer for decoding
auto buffer = vm::ptr<PngBuffer>::make(handle->malloc(ppu, sizeof(PngBuffer), handle->malloc_arg).addr());
// Check for if the buffer structure allocation failed
if (!buffer)
{
throw EXCEPTION("Memory allocation for the PNG buffer structure failed.");
}
// We might not be reading from a file stream
buffer->file = false;
// Set the buffer pointer in the stream structure, so we can later deallocate it
stream->buffer = buffer;
// Open the buffer/file and check the header
u8 header[8];
// Need to test it somewhere
if (stream->source.fileOffset != 0)
{
throw EXCEPTION("Non-0 file offset not supported.");
}
// Depending on the source type, get the first 8 bytes
if (source->srcSelect == CELL_PNGDEC_FILE)
{
// Open a file stream
fs::file file_stream(vfs::get(stream->source.fileName.get_ptr()));
// Check if opening of the PNG file failed
if (!file_stream)
{
cellPngDec.error("Opening of PNG failed. (%s)", stream->source.fileName.get_ptr());
return CELL_PNGDEC_ERROR_OPEN_FILE;
}
// Read the header
if (file_stream.read(header, 8) != 8)
{
cellPngDec.error("PNG header is too small.");
return CELL_PNGDEC_ERROR_HEADER;
}
// Get the file descriptor
buffer->fd = idm::make<lv2_file_t>(std::move(file_stream), 0, 0);
// Indicate that we need to read from a file stream
buffer->file = true;
}
else
{
// We can simply copy the first 8 bytes
memcpy(header, stream->source.streamPtr.get_ptr(), 8);
}
// Check if the header indicates a valid PNG file
if (png_sig_cmp(header, 0, 8))
{
cellPngDec.error("PNG signature is invalid.");
return CELL_PNGDEC_ERROR_HEADER;
}
// Create a libpng structure, also pass our custom error/warning functions
stream->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, pngDecError, pngDecWarning);
// Check if the creation of the structure failed
if (!stream->png_ptr)
{
cellPngDec.error("Creation of png_structp failed.");
return CELL_PNGDEC_ERROR_FATAL;
}
// Create a libpng info structure
stream->info_ptr = png_create_info_struct(stream->png_ptr);
// Check if the creation of the structure failed
if (!stream->info_ptr)
{
throw EXCEPTION("Creation of png_infop failed.");
}
// Set a point to return to when an error occurs in libpng
if (setjmp(png_jmpbuf(stream->png_ptr)))
{
throw EXCEPTION("Fatal error in libpng.");
}
// We must indicate, that we allocated more memory
open_info->initSpaceAllocated += sizeof(PngBuffer);
// Init the IO for either reading from a file or a buffer
if (source->srcSelect == CELL_PNGDEC_BUFFER)
{
// Set the data pointer and the file size
buffer->length = stream->source.fileSize;
buffer->data = stream->source.streamPtr;
// Since we already read the header, we start reading from position 8
buffer->cursor = 8;
}
// Set the custom read function for decoding
png_set_read_fn(stream->png_ptr, buffer.get_ptr(), pngDecReadBuffer);
// We need to tell libpng, that we already read 8 bytes
png_set_sig_bytes(stream->png_ptr, 8);
// Read the basic info of the PNG file
png_read_info(stream->png_ptr, stream->info_ptr);
// Read the header info for future use
stream->info.imageWidth = png_get_image_width(stream->png_ptr, stream->info_ptr);
stream->info.imageHeight = png_get_image_height(stream->png_ptr, stream->info_ptr);
stream->info.numComponents = png_get_channels(stream->png_ptr, stream->info_ptr);
stream->info.colorSpace = getPngDecColourType(png_get_color_type(stream->png_ptr, stream->info_ptr));
stream->info.bitDepth = png_get_bit_depth(stream->png_ptr, stream->info_ptr);
stream->info.interlaceMethod = png_get_interlace_type(stream->png_ptr, stream->info_ptr);
stream->info.chunkInformation = pngDecGetChunkInformation(stream);
return CELL_OK;
}
