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qpdf/libqpdf/Pl_DCT.cc
2022-05-03 18:31:23 -04:00

356 lines
10 KiB
C++

#include <qpdf/Pl_DCT.hh>
#include <qpdf/QIntC.hh>
#include <qpdf/QTC.hh>
#include <qpdf/QUtil.hh>
#include <cstring>
#include <setjmp.h>
#include <stdexcept>
#include <stdlib.h>
#include <string>
#if BITS_IN_JSAMPLE != 8
# error "qpdf does not support libjpeg built with BITS_IN_JSAMPLE != 8"
#endif
namespace
{
struct qpdf_jpeg_error_mgr
{
struct jpeg_error_mgr pub;
jmp_buf jmpbuf;
std::string msg;
};
} // namespace
static void
error_handler(j_common_ptr cinfo)
{
qpdf_jpeg_error_mgr* jerr =
reinterpret_cast<qpdf_jpeg_error_mgr*>(cinfo->err);
char buf[JMSG_LENGTH_MAX];
(*cinfo->err->format_message)(cinfo, buf);
jerr->msg = buf;
longjmp(jerr->jmpbuf, 1);
}
Pl_DCT::Members::Members(
action_e action,
char const* buf_description,
JDIMENSION image_width,
JDIMENSION image_height,
int components,
J_COLOR_SPACE color_space,
CompressConfig* config_callback) :
action(action),
buf(buf_description),
image_width(image_width),
image_height(image_height),
components(components),
color_space(color_space),
config_callback(config_callback)
{
}
Pl_DCT::Pl_DCT(char const* identifier, Pipeline* next) :
Pipeline(identifier, next),
m(new Members(a_decompress, "DCT compressed image"))
{
}
Pl_DCT::Pl_DCT(
char const* identifier,
Pipeline* next,
JDIMENSION image_width,
JDIMENSION image_height,
int components,
J_COLOR_SPACE color_space,
CompressConfig* config_callback) :
Pipeline(identifier, next),
m(new Members(
a_compress,
"DCT uncompressed image",
image_width,
image_height,
components,
color_space,
config_callback))
{
}
Pl_DCT::~Pl_DCT()
{
// Must be explicit and not inline -- see QPDF_DLL_CLASS in
// README-maintainer
}
void
Pl_DCT::write(unsigned char const* data, size_t len)
{
this->m->buf.write(data, len);
}
void
Pl_DCT::finish()
{
this->m->buf.finish();
// Using a std::shared_ptr<Buffer> here and passing it into compress
// and decompress causes a memory leak with setjmp/longjmp. Just
// use a pointer and delete it.
Buffer* b = this->m->buf.getBuffer();
if (b->getSize() == 0) {
// Special case: empty data will never succeed and probably
// means we're calling finish a second time from an exception
// handler.
delete b;
this->getNext()->finish();
return;
}
struct jpeg_compress_struct cinfo_compress;
struct jpeg_decompress_struct cinfo_decompress;
struct qpdf_jpeg_error_mgr jerr;
cinfo_compress.err = jpeg_std_error(&(jerr.pub));
cinfo_decompress.err = jpeg_std_error(&(jerr.pub));
jerr.pub.error_exit = error_handler;
bool error = false;
// The jpeg library is a "C" library, so we use setjmp and longjmp
// for exception handling.
if (setjmp(jerr.jmpbuf) == 0) {
try {
if (this->m->action == a_compress) {
compress(reinterpret_cast<void*>(&cinfo_compress), b);
} else {
decompress(reinterpret_cast<void*>(&cinfo_decompress), b);
}
} catch (std::exception& e) {
// Convert an exception back to a longjmp so we can ensure
// that the right cleanup happens. This will get converted
// back to an exception.
jerr.msg = e.what();
longjmp(jerr.jmpbuf, 1);
}
} else {
error = true;
}
delete b;
if (this->m->action == a_compress) {
jpeg_destroy_compress(&cinfo_compress);
}
if (this->m->action == a_decompress) {
jpeg_destroy_decompress(&cinfo_decompress);
}
if (error) {
throw std::runtime_error(jerr.msg);
}
}
namespace
{
struct dct_pipeline_dest
{
struct jpeg_destination_mgr pub; /* public fields */
unsigned char* buffer;
size_t size;
Pipeline* next;
};
} // namespace
static void
init_pipeline_destination(j_compress_ptr)
{
}
static boolean
empty_pipeline_output_buffer(j_compress_ptr cinfo)
{
QTC::TC("libtests", "Pl_DCT empty_pipeline_output_buffer");
dct_pipeline_dest* dest = reinterpret_cast<dct_pipeline_dest*>(cinfo->dest);
dest->next->write(dest->buffer, dest->size);
dest->pub.next_output_byte = dest->buffer;
dest->pub.free_in_buffer = dest->size;
return TRUE;
}
static void
term_pipeline_destination(j_compress_ptr cinfo)
{
QTC::TC("libtests", "Pl_DCT term_pipeline_destination");
dct_pipeline_dest* dest = reinterpret_cast<dct_pipeline_dest*>(cinfo->dest);
dest->next->write(dest->buffer, dest->size - dest->pub.free_in_buffer);
}
static void
jpeg_pipeline_dest(
j_compress_ptr cinfo, unsigned char* outbuffer, size_t size, Pipeline* next)
{
cinfo->dest = static_cast<struct jpeg_destination_mgr*>(
// line-break
(*cinfo->mem->alloc_small)(
reinterpret_cast<j_common_ptr>(cinfo),
JPOOL_PERMANENT,
sizeof(dct_pipeline_dest)));
dct_pipeline_dest* dest = reinterpret_cast<dct_pipeline_dest*>(cinfo->dest);
dest->pub.init_destination = init_pipeline_destination;
dest->pub.empty_output_buffer = empty_pipeline_output_buffer;
dest->pub.term_destination = term_pipeline_destination;
dest->pub.next_output_byte = dest->buffer = outbuffer;
dest->pub.free_in_buffer = dest->size = size;
dest->next = next;
}
static void
init_buffer_source(j_decompress_ptr)
{
}
static boolean
fill_buffer_input_buffer(j_decompress_ptr)
{
// The whole JPEG data is expected to reside in the supplied memory
// buffer, so any request for more data beyond the given buffer size
// is treated as an error.
throw std::runtime_error("invalid jpeg data reading from buffer");
return TRUE;
}
static void
skip_buffer_input_data(j_decompress_ptr cinfo, long num_bytes)
{
if (num_bytes < 0) {
throw std::runtime_error("reading jpeg: jpeg library requested"
" skipping a negative number of bytes");
}
size_t to_skip = QIntC::to_size(num_bytes);
if ((to_skip > 0) && (to_skip <= cinfo->src->bytes_in_buffer)) {
cinfo->src->next_input_byte += to_skip;
cinfo->src->bytes_in_buffer -= to_skip;
} else if (to_skip != 0) {
cinfo->src->next_input_byte += cinfo->src->bytes_in_buffer;
cinfo->src->bytes_in_buffer = 0;
}
}
static void
term_buffer_source(j_decompress_ptr)
{
}
static void
jpeg_buffer_src(j_decompress_ptr cinfo, Buffer* buffer)
{
cinfo->src = reinterpret_cast<jpeg_source_mgr*>(
// line-break
(*cinfo->mem->alloc_small)(
reinterpret_cast<j_common_ptr>(cinfo),
JPOOL_PERMANENT,
sizeof(jpeg_source_mgr)));
jpeg_source_mgr* src = cinfo->src;
src->init_source = init_buffer_source;
src->fill_input_buffer = fill_buffer_input_buffer;
src->skip_input_data = skip_buffer_input_data;
src->resync_to_restart = jpeg_resync_to_restart; /* use default method */
src->term_source = term_buffer_source;
src->bytes_in_buffer = buffer->getSize();
src->next_input_byte = buffer->getBuffer();
}
void
Pl_DCT::compress(void* cinfo_p, Buffer* b)
{
struct jpeg_compress_struct* cinfo =
reinterpret_cast<jpeg_compress_struct*>(cinfo_p);
#if ( \
(defined(__GNUC__) && ((__GNUC__ * 100) + __GNUC_MINOR__) >= 406) || \
defined(__clang__))
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wold-style-cast"
#endif
jpeg_create_compress(cinfo);
#if ( \
(defined(__GNUC__) && ((__GNUC__ * 100) + __GNUC_MINOR__) >= 406) || \
defined(__clang__))
# pragma GCC diagnostic pop
#endif
static int const BUF_SIZE = 65536;
auto outbuffer_ph = std::make_unique<unsigned char[]>(BUF_SIZE);
unsigned char* outbuffer = outbuffer_ph.get();
jpeg_pipeline_dest(cinfo, outbuffer, BUF_SIZE, this->getNext());
cinfo->image_width = this->m->image_width;
cinfo->image_height = this->m->image_height;
cinfo->input_components = this->m->components;
cinfo->in_color_space = this->m->color_space;
jpeg_set_defaults(cinfo);
if (this->m->config_callback) {
this->m->config_callback->apply(cinfo);
}
jpeg_start_compress(cinfo, TRUE);
unsigned int width =
cinfo->image_width * QIntC::to_uint(cinfo->input_components);
size_t expected_size = QIntC::to_size(cinfo->image_height) *
QIntC::to_size(cinfo->image_width) *
QIntC::to_size(cinfo->input_components);
if (b->getSize() != expected_size) {
throw std::runtime_error(
"Pl_DCT: image buffer size = " +
QUtil::uint_to_string(b->getSize()) +
"; expected size = " + QUtil::uint_to_string(expected_size));
}
JSAMPROW row_pointer[1];
unsigned char* buffer = b->getBuffer();
while (cinfo->next_scanline < cinfo->image_height) {
// We already verified that the buffer is big enough.
row_pointer[0] = &buffer[cinfo->next_scanline * width];
(void)jpeg_write_scanlines(cinfo, row_pointer, 1);
}
jpeg_finish_compress(cinfo);
this->getNext()->finish();
}
void
Pl_DCT::decompress(void* cinfo_p, Buffer* b)
{
struct jpeg_decompress_struct* cinfo =
reinterpret_cast<jpeg_decompress_struct*>(cinfo_p);
#if ( \
(defined(__GNUC__) && ((__GNUC__ * 100) + __GNUC_MINOR__) >= 406) || \
defined(__clang__))
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wold-style-cast"
#endif
jpeg_create_decompress(cinfo);
#if ( \
(defined(__GNUC__) && ((__GNUC__ * 100) + __GNUC_MINOR__) >= 406) || \
defined(__clang__))
# pragma GCC diagnostic pop
#endif
jpeg_buffer_src(cinfo, b);
(void)jpeg_read_header(cinfo, TRUE);
(void)jpeg_calc_output_dimensions(cinfo);
unsigned int width =
cinfo->output_width * QIntC::to_uint(cinfo->output_components);
JSAMPARRAY buffer = (*cinfo->mem->alloc_sarray)(
reinterpret_cast<j_common_ptr>(cinfo), JPOOL_IMAGE, width, 1);
(void)jpeg_start_decompress(cinfo);
while (cinfo->output_scanline < cinfo->output_height) {
(void)jpeg_read_scanlines(cinfo, buffer, 1);
this->getNext()->write(buffer[0], width * sizeof(buffer[0][0]));
}
(void)jpeg_finish_decompress(cinfo);
this->getNext()->finish();
}