diff options
Diffstat (limited to 'libqpdf/Pl_DCT.cc')
| -rw-r--r-- | libqpdf/Pl_DCT.cc | 152 |
1 files changed, 130 insertions, 22 deletions
diff --git a/libqpdf/Pl_DCT.cc b/libqpdf/Pl_DCT.cc index b341939e..0853f01d 100644 --- a/libqpdf/Pl_DCT.cc +++ b/libqpdf/Pl_DCT.cc @@ -1,6 +1,7 @@ #include <qpdf/Pl_DCT.hh> #include <qpdf/QUtil.hh> +#include <qpdf/QTC.hh> #include <setjmp.h> #include <string> #include <stdexcept> @@ -80,15 +81,28 @@ Pl_DCT::finish() // and decompress causes a memory leak with setjmp/longjmp. Just // use a pointer and delete it. Buffer* b = this->buf.getBuffer(); + // The jpeg library is a "C" library, so we use setjmp and longjmp + // for exceptoin handling. if (setjmp(jerr.jmpbuf) == 0) { - if (this->action == a_compress) + try { - compress(reinterpret_cast<void*>(&cinfo_compress), b); + if (this->action == a_compress) + { + compress(reinterpret_cast<void*>(&cinfo_compress), b); + } + else + { + decompress(reinterpret_cast<void*>(&cinfo_decompress), b); + } } - else + catch (std::exception& e) { - decompress(reinterpret_cast<void*>(&cinfo_decompress), b); + // 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 @@ -111,24 +125,118 @@ Pl_DCT::finish() } } -class Freer +struct dct_pipeline_dest { - public: - Freer(unsigned char** p) : - p(p) + struct jpeg_destination_mgr pub; /* public fields */ + unsigned char* buffer; + size_t size; + Pipeline* next; +}; + +static void +init_pipeline_destination(j_compress_ptr) +{ +} + +static int +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 *>( + (*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 int +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"); } - ~Freer() + size_t to_skip = static_cast<size_t>(num_bytes); + if ((to_skip > 0) && (to_skip <= cinfo->src->bytes_in_buffer)) { - if (*p) - { - free(*p); - } + 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; } +} - private: - unsigned char** p; -}; +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 *>( + (*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) @@ -146,10 +254,11 @@ Pl_DCT::compress(void* cinfo_p, Buffer* b) defined(__clang__)) # pragma GCC diagnostic pop #endif - unsigned char* outbuffer = 0; - Freer freer(&outbuffer); - unsigned long outsize = 0; - jpeg_mem_dest(cinfo, &outbuffer, &outsize); + static int const BUF_SIZE = 65536; + PointerHolder<unsigned char> outbuffer_ph( + true, new unsigned char[BUF_SIZE]); + unsigned char* outbuffer = outbuffer_ph.getPointer(); + jpeg_pipeline_dest(cinfo, outbuffer, BUF_SIZE, this->getNext()); cinfo->image_width = this->image_width; cinfo->image_height = this->image_height; @@ -182,7 +291,6 @@ Pl_DCT::compress(void* cinfo_p, Buffer* b) (void) jpeg_write_scanlines(cinfo, row_pointer, 1); } jpeg_finish_compress(cinfo); - this->getNext()->write(outbuffer, outsize); this->getNext()->finish(); } @@ -202,7 +310,7 @@ Pl_DCT::decompress(void* cinfo_p, Buffer* b) defined(__clang__)) # pragma GCC diagnostic pop #endif - jpeg_mem_src(cinfo, b->getBuffer(), b->getSize()); + jpeg_buffer_src(cinfo, b); (void) jpeg_read_header(cinfo, TRUE); (void) jpeg_calc_output_dimensions(cinfo); |