void /* PRIVATE */ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length) { int ret; if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length) png_error(png_ptr, "Extra compression data"); png_ptr->zstream.next_in = buffer; png_ptr->zstream.avail_in = (uInt)buffer_length; for(;;) { ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); if (ret != Z_OK) { if (ret == Z_STREAM_END) { if (png_ptr->zstream.avail_in) png_error(png_ptr, "Extra compressed data"); if (!(png_ptr->zstream.avail_out)) { png_push_process_row(png_ptr); } png_ptr->mode |= PNG_AFTER_IDAT; png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; break; } else if (ret == Z_BUF_ERROR) break; else png_error(png_ptr, "Decompression Error"); } if (!(png_ptr->zstream.avail_out)) { if (( #if defined(PNG_READ_INTERLACING_SUPPORTED) png_ptr->interlaced && png_ptr->pass > 6) || (!png_ptr->interlaced && #endif png_ptr->row_number == png_ptr->num_rows)) { if (png_ptr->zstream.avail_in) { png_warning(png_ptr, "Too much data in IDAT chunks"); } png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; break; } png_push_process_row(png_ptr); png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; png_ptr->zstream.next_out = png_ptr->row_buf; } else break; } }
void /* PRIVATE */ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length) { int ret; if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length) png_error(png_ptr, "Extra compression data"); png_ptr->zstream.next_in = buffer; png_ptr->zstream.avail_in = (uInt)buffer_length; for(;;) { ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); if (ret != Z_OK) { if (ret == Z_STREAM_END) { if (png_ptr->zstream.avail_in) png_error(png_ptr, "Extra compressed data"); if (!(png_ptr->zstream.avail_out)) { png_push_process_row(png_ptr); } png_ptr->mode |= PNG_AFTER_IDAT; png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; break; } else if (ret == Z_BUF_ERROR) break; else png_error(png_ptr, "Decompression Error"); } if (!(png_ptr->zstream.avail_out)) { png_push_process_row(png_ptr); png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; png_ptr->zstream.next_out = png_ptr->row_buf; } else break; } }
void /* PRIVATE */ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length) { /* The caller checks for a non-zero buffer length. */ if (!(buffer_length > 0) || buffer == NULL) png_error(png_ptr, "No IDAT data (internal error)"); /* This routine must process all the data it has been given * before returning, calling the row callback as required to * handle the uncompressed results. */ png_ptr->zstream.next_in = buffer; png_ptr->zstream.avail_in = (uInt)buffer_length; /* Keep going until the decompressed data is all processed * or the stream marked as finished. */ while (png_ptr->zstream.avail_in > 0 && !(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) { int ret; /* We have data for zlib, but we must check that zlib * has somewhere to put the results. It doesn't matter * if we don't expect any results -- it may be the input * data is just the LZ end code. */ if (!(png_ptr->zstream.avail_out > 0)) { png_ptr->zstream.avail_out = (uInt) PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1; png_ptr->zstream.next_out = png_ptr->row_buf; } /* Using Z_SYNC_FLUSH here means that an unterminated * LZ stream can still be handled (a stream with a missing * end code), otherwise (Z_NO_FLUSH) a future zlib * implementation might defer output and, therefore, * change the current behavior. (See comments in inflate.c * for why this doesn't happen at present with zlib 1.2.5.) */ ret = inflate(&png_ptr->zstream, Z_SYNC_FLUSH); /* Check for any failure before proceeding. */ if (ret != Z_OK && ret != Z_STREAM_END) { /* Terminate the decompression. */ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; /* This may be a truncated stream (missing or * damaged end code). Treat that as a warning. */ if (png_ptr->row_number >= png_ptr->num_rows || png_ptr->pass > 6) png_warning(png_ptr, "Truncated compressed data in IDAT"); else png_error(png_ptr, "Decompression error in IDAT"); /* Skip the check on unprocessed input */ return; } /* Did inflate output any data? */ if (png_ptr->zstream.next_out != png_ptr->row_buf) { /* Is this unexpected data after the last row? * If it is, artificially terminate the LZ output * here. */ if (png_ptr->row_number >= png_ptr->num_rows || png_ptr->pass > 6) { /* Extra data. */ png_warning(png_ptr, "Extra compressed data in IDAT"); png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; /* Do no more processing; skip the unprocessed * input check below. */ return; } /* Do we have a complete row? */ if (png_ptr->zstream.avail_out == 0) png_push_process_row(png_ptr); } /* And check for the end of the stream. */ if (ret == Z_STREAM_END) png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; } /* All the data should have been processed, if anything * is left at this point we have bytes of IDAT data * after the zlib end code. */ if (png_ptr->zstream.avail_in > 0) png_warning(png_ptr, "Extra compression data"); }
void /* PRIVATE */ png_process_IDAT_data(png_structrp png_ptr, png_bytep buffer, png_size_t buffer_length) { /* The caller checks for a non-zero buffer length. */ if (!(buffer_length > 0) || buffer == NULL) png_error(png_ptr, "No IDAT data (internal error)"); #ifdef PNG_READ_APNG_SUPPORTED /* If the app is not APNG-aware, decode only the first frame */ if ((png_ptr->apng_flags & PNG_APNG_APP) == 0 && png_ptr->num_frames_read > 0) { png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; return; } #endif /* This routine must process all the data it has been given * before returning, calling the row callback as required to * handle the uncompressed results. */ png_ptr->zstream.next_in = buffer; /* TODO: WARNING: TRUNCATION ERROR: DANGER WILL ROBINSON: */ png_ptr->zstream.avail_in = (uInt)buffer_length; /* Keep going until the decompressed data is all processed * or the stream marked as finished. */ while (png_ptr->zstream.avail_in > 0 && (png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0) { int ret; /* We have data for zlib, but we must check that zlib * has someplace to put the results. It doesn't matter * if we don't expect any results -- it may be the input * data is just the LZ end code. */ if (!(png_ptr->zstream.avail_out > 0)) { /* TODO: WARNING: TRUNCATION ERROR: DANGER WILL ROBINSON: */ png_ptr->zstream.avail_out = (uInt)(PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1); png_ptr->zstream.next_out = png_ptr->row_buf; } /* Using Z_SYNC_FLUSH here means that an unterminated * LZ stream (a stream with a missing end code) can still * be handled, otherwise (Z_NO_FLUSH) a future zlib * implementation might defer output and therefore * change the current behavior (see comments in inflate.c * for why this doesn't happen at present with zlib 1.2.5). */ ret = PNG_INFLATE(png_ptr, Z_SYNC_FLUSH); /* Check for any failure before proceeding. */ if (ret != Z_OK && ret != Z_STREAM_END) { /* Terminate the decompression. */ png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; png_ptr->zowner = 0; /* This may be a truncated stream (missing or * damaged end code). Treat that as a warning. */ if (png_ptr->row_number >= png_ptr->num_rows || png_ptr->pass > 6) png_warning(png_ptr, "Truncated compressed data in IDAT"); else { if (ret == Z_DATA_ERROR) png_benign_error(png_ptr, "IDAT: ADLER32 checksum mismatch"); else png_error(png_ptr, "Decompression error in IDAT"); } /* Skip the check on unprocessed input */ return; } /* Did inflate output any data? */ if (png_ptr->zstream.next_out != png_ptr->row_buf) { /* Is this unexpected data after the last row? * If it is, artificially terminate the LZ output * here. */ if (png_ptr->row_number >= png_ptr->num_rows || png_ptr->pass > 6) { /* Extra data. */ png_warning(png_ptr, "Extra compressed data in IDAT"); png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; png_ptr->zowner = 0; /* Do no more processing; skip the unprocessed * input check below. */ return; } /* Do we have a complete row? */ if (png_ptr->zstream.avail_out == 0) png_push_process_row(png_ptr); } /* And check for the end of the stream. */ if (ret == Z_STREAM_END) png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; } /* All the data should have been processed, if anything * is left at this point we have bytes of IDAT data * after the zlib end code. */ if (png_ptr->zstream.avail_in > 0) png_warning(png_ptr, "Extra compression data in IDAT"); }