/* Read the end of the PNG file. Will not read past the end of the * file, will verify the end is accurate, and will read any comments * or time information at the end of the file, if info is not NULL. */ void PNGAPI png_read_end(png_structp png_ptr, png_infop info_ptr) { png_debug(1, "in png_read_end"); if (png_ptr == NULL) return; png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ do { PNG_IHDR; PNG_IDAT; PNG_IEND; PNG_PLTE; #ifdef PNG_READ_bKGD_SUPPORTED PNG_bKGD; #endif #ifdef PNG_READ_cHRM_SUPPORTED PNG_cHRM; #endif #ifdef PNG_READ_gAMA_SUPPORTED PNG_gAMA; #endif #ifdef PNG_READ_hIST_SUPPORTED PNG_hIST; #endif #ifdef PNG_READ_iCCP_SUPPORTED PNG_iCCP; #endif #ifdef PNG_READ_iTXt_SUPPORTED PNG_iTXt; #endif #ifdef PNG_READ_oFFs_SUPPORTED PNG_oFFs; #endif #ifdef PNG_READ_pCAL_SUPPORTED PNG_pCAL; #endif #ifdef PNG_READ_pHYs_SUPPORTED PNG_pHYs; #endif #ifdef PNG_READ_sBIT_SUPPORTED PNG_sBIT; #endif #ifdef PNG_READ_sCAL_SUPPORTED PNG_sCAL; #endif #ifdef PNG_READ_sPLT_SUPPORTED PNG_sPLT; #endif #ifdef PNG_READ_sRGB_SUPPORTED PNG_sRGB; #endif #ifdef PNG_READ_tEXt_SUPPORTED PNG_tEXt; #endif #ifdef PNG_READ_tIME_SUPPORTED PNG_tIME; #endif #ifdef PNG_READ_tRNS_SUPPORTED PNG_tRNS; #endif #ifdef PNG_READ_zTXt_SUPPORTED PNG_zTXt; #endif png_uint_32 length = png_read_chunk_header(png_ptr); PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; if (!png_memcmp(chunk_name, png_IHDR, 4)) png_handle_IHDR(png_ptr, info_ptr, length); else if (!png_memcmp(chunk_name, png_IEND, 4)) png_handle_IEND(png_ptr, info_ptr, length); #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED else if (png_handle_as_unknown(png_ptr, chunk_name)) { if (!png_memcmp(chunk_name, png_IDAT, 4)) { if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) png_benign_error(png_ptr, "Too many IDATs found"); } png_handle_unknown(png_ptr, info_ptr, length); if (!png_memcmp(chunk_name, png_PLTE, 4)) png_ptr->mode |= PNG_HAVE_PLTE; } #endif else if (!png_memcmp(chunk_name, png_IDAT, 4)) { /* Zero length IDATs are legal after the last IDAT has been * read, but not after other chunks have been read. */ if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) png_benign_error(png_ptr, "Too many IDATs found"); png_crc_finish(png_ptr, length); } else if (!png_memcmp(chunk_name, png_PLTE, 4)) png_handle_PLTE(png_ptr, info_ptr, length); #ifdef PNG_READ_bKGD_SUPPORTED else if (!png_memcmp(chunk_name, png_bKGD, 4)) png_handle_bKGD(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_cHRM_SUPPORTED else if (!png_memcmp(chunk_name, png_cHRM, 4)) png_handle_cHRM(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_gAMA_SUPPORTED else if (!png_memcmp(chunk_name, png_gAMA, 4)) png_handle_gAMA(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_hIST_SUPPORTED else if (!png_memcmp(chunk_name, png_hIST, 4)) png_handle_hIST(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_oFFs_SUPPORTED else if (!png_memcmp(chunk_name, png_oFFs, 4)) png_handle_oFFs(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_pCAL_SUPPORTED else if (!png_memcmp(chunk_name, png_pCAL, 4)) png_handle_pCAL(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sCAL_SUPPORTED else if (!png_memcmp(chunk_name, png_sCAL, 4)) png_handle_sCAL(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_pHYs_SUPPORTED else if (!png_memcmp(chunk_name, png_pHYs, 4)) png_handle_pHYs(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sBIT_SUPPORTED else if (!png_memcmp(chunk_name, png_sBIT, 4)) png_handle_sBIT(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sRGB_SUPPORTED else if (!png_memcmp(chunk_name, png_sRGB, 4)) png_handle_sRGB(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_iCCP_SUPPORTED else if (!png_memcmp(chunk_name, png_iCCP, 4)) png_handle_iCCP(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sPLT_SUPPORTED else if (!png_memcmp(chunk_name, png_sPLT, 4)) png_handle_sPLT(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tEXt_SUPPORTED else if (!png_memcmp(chunk_name, png_tEXt, 4)) png_handle_tEXt(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tIME_SUPPORTED else if (!png_memcmp(chunk_name, png_tIME, 4)) png_handle_tIME(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tRNS_SUPPORTED else if (!png_memcmp(chunk_name, png_tRNS, 4)) png_handle_tRNS(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_zTXt_SUPPORTED else if (!png_memcmp(chunk_name, png_zTXt, 4)) png_handle_zTXt(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_iTXt_SUPPORTED else if (!png_memcmp(chunk_name, png_iTXt, 4)) png_handle_iTXt(png_ptr, info_ptr, length); #endif else png_handle_unknown(png_ptr, info_ptr, length); } while (!(png_ptr->mode & PNG_HAVE_IEND)); }
/* Read the information before the actual image data. This has been * changed in v0.90 to allow reading a file that already has the magic * bytes read from the stream. You can tell libpng how many bytes have * been read from the beginning of the stream (up to the maximum of 8) * via png_set_sig_bytes(), and we will only check the remaining bytes * here. The application can then have access to the signature bytes we * read if it is determined that this isn't a valid PNG file. */ void PNGAPI png_read_info(png_structp png_ptr, png_infop info_ptr) { png_debug(1, "in png_read_info"); if (png_ptr == NULL || info_ptr == NULL) return; /* Read and check the PNG file signature. */ png_read_sig(png_ptr, info_ptr); for (;;) { PNG_IHDR; PNG_IDAT; PNG_IEND; PNG_PLTE; #ifdef PNG_READ_bKGD_SUPPORTED PNG_bKGD; #endif #ifdef PNG_READ_cHRM_SUPPORTED PNG_cHRM; #endif #ifdef PNG_READ_gAMA_SUPPORTED PNG_gAMA; #endif #ifdef PNG_READ_hIST_SUPPORTED PNG_hIST; #endif #ifdef PNG_READ_iCCP_SUPPORTED PNG_iCCP; #endif #ifdef PNG_READ_iTXt_SUPPORTED PNG_iTXt; #endif #ifdef PNG_READ_oFFs_SUPPORTED PNG_oFFs; #endif #ifdef PNG_READ_pCAL_SUPPORTED PNG_pCAL; #endif #ifdef PNG_READ_pHYs_SUPPORTED PNG_pHYs; #endif #ifdef PNG_READ_sBIT_SUPPORTED PNG_sBIT; #endif #ifdef PNG_READ_sCAL_SUPPORTED PNG_sCAL; #endif #ifdef PNG_READ_sPLT_SUPPORTED PNG_sPLT; #endif #ifdef PNG_READ_sRGB_SUPPORTED PNG_sRGB; #endif #ifdef PNG_READ_tEXt_SUPPORTED PNG_tEXt; #endif #ifdef PNG_READ_tIME_SUPPORTED PNG_tIME; #endif #ifdef PNG_READ_tRNS_SUPPORTED PNG_tRNS; #endif #ifdef PNG_READ_zTXt_SUPPORTED PNG_zTXt; #endif png_uint_32 length = png_read_chunk_header(png_ptr); PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; /* This should be a binary subdivision search or a hash for * matching the chunk name rather than a linear search. */ if (!png_memcmp(chunk_name, png_IDAT, 4)) if (png_ptr->mode & PNG_AFTER_IDAT) png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; if (!png_memcmp(chunk_name, png_IHDR, 4)) png_handle_IHDR(png_ptr, info_ptr, length); else if (!png_memcmp(chunk_name, png_IEND, 4)) png_handle_IEND(png_ptr, info_ptr, length); #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED else if (png_handle_as_unknown(png_ptr, chunk_name)) { if (!png_memcmp(chunk_name, png_IDAT, 4)) png_ptr->mode |= PNG_HAVE_IDAT; png_handle_unknown(png_ptr, info_ptr, length); if (!png_memcmp(chunk_name, png_PLTE, 4)) png_ptr->mode |= PNG_HAVE_PLTE; else if (!png_memcmp(chunk_name, png_IDAT, 4)) { if (!(png_ptr->mode & PNG_HAVE_IHDR)) png_error(png_ptr, "Missing IHDR before IDAT"); else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && !(png_ptr->mode & PNG_HAVE_PLTE)) png_error(png_ptr, "Missing PLTE before IDAT"); break; } } #endif else if (!png_memcmp(chunk_name, png_PLTE, 4)) png_handle_PLTE(png_ptr, info_ptr, length); else if (!png_memcmp(chunk_name, png_IDAT, 4)) { if (!(png_ptr->mode & PNG_HAVE_IHDR)) png_error(png_ptr, "Missing IHDR before IDAT"); else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && !(png_ptr->mode & PNG_HAVE_PLTE)) png_error(png_ptr, "Missing PLTE before IDAT"); png_ptr->idat_size = length; png_ptr->mode |= PNG_HAVE_IDAT; break; } #ifdef PNG_READ_bKGD_SUPPORTED else if (!png_memcmp(chunk_name, png_bKGD, 4)) png_handle_bKGD(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_cHRM_SUPPORTED else if (!png_memcmp(chunk_name, png_cHRM, 4)) png_handle_cHRM(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_gAMA_SUPPORTED else if (!png_memcmp(chunk_name, png_gAMA, 4)) png_handle_gAMA(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_hIST_SUPPORTED else if (!png_memcmp(chunk_name, png_hIST, 4)) png_handle_hIST(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_oFFs_SUPPORTED else if (!png_memcmp(chunk_name, png_oFFs, 4)) png_handle_oFFs(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_pCAL_SUPPORTED else if (!png_memcmp(chunk_name, png_pCAL, 4)) png_handle_pCAL(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sCAL_SUPPORTED else if (!png_memcmp(chunk_name, png_sCAL, 4)) png_handle_sCAL(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_pHYs_SUPPORTED else if (!png_memcmp(chunk_name, png_pHYs, 4)) png_handle_pHYs(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sBIT_SUPPORTED else if (!png_memcmp(chunk_name, png_sBIT, 4)) png_handle_sBIT(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sRGB_SUPPORTED else if (!png_memcmp(chunk_name, png_sRGB, 4)) png_handle_sRGB(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_iCCP_SUPPORTED else if (!png_memcmp(chunk_name, png_iCCP, 4)) png_handle_iCCP(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_sPLT_SUPPORTED else if (!png_memcmp(chunk_name, png_sPLT, 4)) png_handle_sPLT(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tEXt_SUPPORTED else if (!png_memcmp(chunk_name, png_tEXt, 4)) png_handle_tEXt(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tIME_SUPPORTED else if (!png_memcmp(chunk_name, png_tIME, 4)) png_handle_tIME(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_tRNS_SUPPORTED else if (!png_memcmp(chunk_name, png_tRNS, 4)) png_handle_tRNS(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_zTXt_SUPPORTED else if (!png_memcmp(chunk_name, png_zTXt, 4)) png_handle_zTXt(png_ptr, info_ptr, length); #endif #ifdef PNG_READ_iTXt_SUPPORTED else if (!png_memcmp(chunk_name, png_iTXt, 4)) png_handle_iTXt(png_ptr, info_ptr, length); #endif else png_handle_unknown(png_ptr, info_ptr, length); } }
void PNGAPI png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) { PNG_IDAT; PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff}; PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; int ret; if (png_ptr == NULL) return; png_debug2(1, "in png_read_row (row %lu, pass %d)", (unsigned long) png_ptr->row_number, png_ptr->pass); if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) png_read_start_row(png_ptr); if (png_ptr->row_number == 0 && png_ptr->pass == 0) { /* Check for transforms that have been set but were defined out */ #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) if (png_ptr->transformations & PNG_INVERT_MONO) png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) if (png_ptr->transformations & PNG_FILLER) png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \ !defined(PNG_READ_PACKSWAP_SUPPORTED) if (png_ptr->transformations & PNG_PACKSWAP) png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) if (png_ptr->transformations & PNG_PACK) png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) if (png_ptr->transformations & PNG_SHIFT) png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) if (png_ptr->transformations & PNG_BGR) png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined"); #endif #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) if (png_ptr->transformations & PNG_SWAP_BYTES) png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined"); #endif } #ifdef PNG_READ_INTERLACING_SUPPORTED /* If interlaced and we do not need a new row, combine row and return */ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) { switch (png_ptr->pass) { case 0: if (png_ptr->row_number & 0x07) { if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; case 1: if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) { if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; case 2: if ((png_ptr->row_number & 0x07) != 4) { if (dsp_row != NULL && (png_ptr->row_number & 4)) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; case 3: if ((png_ptr->row_number & 3) || png_ptr->width < 3) { if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; case 4: if ((png_ptr->row_number & 3) != 2) { if (dsp_row != NULL && (png_ptr->row_number & 2)) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; case 5: if ((png_ptr->row_number & 1) || png_ptr->width < 2) { if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); png_read_finish_row(png_ptr); return; } break; default: case 6: if (!(png_ptr->row_number & 1)) { png_read_finish_row(png_ptr); return; } break; } } #endif if (!(png_ptr->mode & PNG_HAVE_IDAT)) png_error(png_ptr, "Invalid attempt to read row data"); png_ptr->zstream.next_out = png_ptr->row_buf; png_ptr->zstream.avail_out = (uInt)(PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1); do { if (!(png_ptr->zstream.avail_in)) { while (!png_ptr->idat_size) { png_crc_finish(png_ptr, 0); png_ptr->idat_size = png_read_chunk_header(png_ptr); if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) png_error(png_ptr, "Not enough image data"); } png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; png_ptr->zstream.next_in = png_ptr->zbuf; if (png_ptr->zbuf_size > png_ptr->idat_size) png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; png_crc_read(png_ptr, png_ptr->zbuf, (png_size_t)png_ptr->zstream.avail_in); png_ptr->idat_size -= png_ptr->zstream.avail_in; } ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); if (ret == Z_STREAM_END) { if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || png_ptr->idat_size) png_benign_error(png_ptr, "Extra compressed data"); png_ptr->mode |= PNG_AFTER_IDAT; png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; break; } if (ret != Z_OK) png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : "Decompression error"); } while (png_ptr->zstream.avail_out); png_ptr->row_info.color_type = png_ptr->color_type; png_ptr->row_info.width = png_ptr->iwidth; png_ptr->row_info.channels = png_ptr->channels; png_ptr->row_info.bit_depth = png_ptr->bit_depth; png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->row_info.width); if (png_ptr->row_buf[0]) png_read_filter_row(png_ptr, &(png_ptr->row_info), png_ptr->row_buf + 1, png_ptr->prev_row + 1, (int)(png_ptr->row_buf[0])); png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1); #ifdef PNG_MNG_FEATURES_SUPPORTED if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) { /* Intrapixel differencing */ png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); } #endif if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) png_do_read_transformations(png_ptr); #ifdef PNG_READ_INTERLACING_SUPPORTED /* Blow up interlaced rows to full size */ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) { if (png_ptr->pass < 6) /* Old interface (pre-1.0.9): * png_do_read_interlace(&(png_ptr->row_info), * png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); */ png_do_read_interlace(png_ptr); if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, png_pass_dsp_mask[png_ptr->pass]); if (row != NULL) png_combine_row(png_ptr, row, png_pass_mask[png_ptr->pass]); } else #endif { if (row != NULL) png_combine_row(png_ptr, row, 0xff); if (dsp_row != NULL) png_combine_row(png_ptr, dsp_row, 0xff); } png_read_finish_row(png_ptr); if (png_ptr->read_row_fn != NULL) (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); }
/* Read the information before the actual image data. This has been * changed in v0.90 to allow reading a file that already has the magic * bytes read from the stream. You can tell libpng how many bytes have * been read from the beginning of the stream (up to the maximum of 8) * via png_set_sig_bytes(), and we will only check the remaining bytes * here. The application can then have access to the signature bytes we * read if it is determined that this isn't a valid PNG file. */ void PNGAPI png_read_info(png_structp png_ptr, png_infop info_ptr) { if (png_ptr == NULL || info_ptr == NULL) return; png_debug(1, "in png_read_info\n"); /* If we haven't checked all of the PNG signature bytes, do so now. */ if (png_ptr->sig_bytes < 8) { png_size_t num_checked = png_ptr->sig_bytes, num_to_check = 8 - num_checked; png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); png_ptr->sig_bytes = 8; if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) { if (num_checked < 4 && png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) png_error(png_ptr, "Not a PNG file"); else png_error(png_ptr, "PNG file corrupted by ASCII conversion"); } if (num_checked < 3) png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; } for (;;) { #ifdef PNG_USE_LOCAL_ARRAYS PNG_CONST PNG_IHDR; PNG_CONST PNG_IDAT; PNG_CONST PNG_IEND; PNG_CONST PNG_PLTE; #if defined(PNG_READ_bKGD_SUPPORTED) PNG_CONST PNG_bKGD; #endif #if defined(PNG_READ_cHRM_SUPPORTED) PNG_CONST PNG_cHRM; #endif #if defined(PNG_READ_gAMA_SUPPORTED) PNG_CONST PNG_gAMA; #endif #if defined(PNG_READ_hIST_SUPPORTED) PNG_CONST PNG_hIST; #endif #if defined(PNG_READ_iCCP_SUPPORTED) PNG_CONST PNG_iCCP; #endif #if defined(PNG_READ_iTXt_SUPPORTED) PNG_CONST PNG_iTXt; #endif #if defined(PNG_READ_oFFs_SUPPORTED) PNG_CONST PNG_oFFs; #endif #if defined(PNG_READ_pCAL_SUPPORTED) PNG_CONST PNG_pCAL; #endif #if defined(PNG_READ_pHYs_SUPPORTED) PNG_CONST PNG_pHYs; #endif #if defined(PNG_READ_sBIT_SUPPORTED) PNG_CONST PNG_sBIT; #endif #if defined(PNG_READ_sCAL_SUPPORTED) PNG_CONST PNG_sCAL; #endif #if defined(PNG_READ_sPLT_SUPPORTED) PNG_CONST PNG_sPLT; #endif #if defined(PNG_READ_sRGB_SUPPORTED) PNG_CONST PNG_sRGB; #endif #if defined(PNG_READ_tEXt_SUPPORTED) PNG_CONST PNG_tEXt; #endif #if defined(PNG_READ_tIME_SUPPORTED) PNG_CONST PNG_tIME; #endif #if defined(PNG_READ_tRNS_SUPPORTED) PNG_CONST PNG_tRNS; #endif #if defined(PNG_READ_zTXt_SUPPORTED) PNG_CONST PNG_zTXt; #endif #endif /* PNG_USE_LOCAL_ARRAYS */ png_uint_32 length = png_read_chunk_header(png_ptr); PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; /* This should be a binary subdivision search or a hash for * matching the chunk name rather than a linear search. */ if (!png_memcmp(chunk_name, png_IDAT, 4)) if (png_ptr->mode & PNG_AFTER_IDAT) png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; if (!png_memcmp(chunk_name, png_IHDR, 4)) png_handle_IHDR(png_ptr, info_ptr, length); else if (!png_memcmp(chunk_name, png_IEND, 4)) png_handle_IEND(png_ptr, info_ptr, length); #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED else if (png_handle_as_unknown(png_ptr, chunk_name)) { if (!png_memcmp(chunk_name, png_IDAT, 4)) png_ptr->mode |= PNG_HAVE_IDAT; png_handle_unknown(png_ptr, info_ptr, length); if (!png_memcmp(chunk_name, png_PLTE, 4)) png_ptr->mode |= PNG_HAVE_PLTE; else if (!png_memcmp(chunk_name, png_IDAT, 4)) { if (!(png_ptr->mode & PNG_HAVE_IHDR)) png_error(png_ptr, "Missing IHDR before IDAT"); else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && !(png_ptr->mode & PNG_HAVE_PLTE)) png_error(png_ptr, "Missing PLTE before IDAT"); break; } } #endif else if (!png_memcmp(chunk_name, png_PLTE, 4)) png_handle_PLTE(png_ptr, info_ptr, length); else if (!png_memcmp(chunk_name, png_IDAT, 4)) { if (!(png_ptr->mode & PNG_HAVE_IHDR)) png_error(png_ptr, "Missing IHDR before IDAT"); else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && !(png_ptr->mode & PNG_HAVE_PLTE)) png_error(png_ptr, "Missing PLTE before IDAT"); png_ptr->idat_size = length; png_ptr->mode |= PNG_HAVE_IDAT; break; } #if defined(PNG_READ_bKGD_SUPPORTED) else if (!png_memcmp(chunk_name, png_bKGD, 4)) png_handle_bKGD(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_cHRM_SUPPORTED) else if (!png_memcmp(chunk_name, png_cHRM, 4)) png_handle_cHRM(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_gAMA_SUPPORTED) else if (!png_memcmp(chunk_name, png_gAMA, 4)) png_handle_gAMA(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_hIST_SUPPORTED) else if (!png_memcmp(chunk_name, png_hIST, 4)) png_handle_hIST(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_oFFs_SUPPORTED) else if (!png_memcmp(chunk_name, png_oFFs, 4)) png_handle_oFFs(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_pCAL_SUPPORTED) else if (!png_memcmp(chunk_name, png_pCAL, 4)) png_handle_pCAL(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_sCAL_SUPPORTED) else if (!png_memcmp(chunk_name, png_sCAL, 4)) png_handle_sCAL(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_pHYs_SUPPORTED) else if (!png_memcmp(chunk_name, png_pHYs, 4)) png_handle_pHYs(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_sBIT_SUPPORTED) else if (!png_memcmp(chunk_name, png_sBIT, 4)) png_handle_sBIT(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_sRGB_SUPPORTED) else if (!png_memcmp(chunk_name, png_sRGB, 4)) png_handle_sRGB(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_iCCP_SUPPORTED) else if (!png_memcmp(chunk_name, png_iCCP, 4)) png_handle_iCCP(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_sPLT_SUPPORTED) else if (!png_memcmp(chunk_name, png_sPLT, 4)) png_handle_sPLT(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_tEXt_SUPPORTED) else if (!png_memcmp(chunk_name, png_tEXt, 4)) png_handle_tEXt(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_tIME_SUPPORTED) else if (!png_memcmp(chunk_name, png_tIME, 4)) png_handle_tIME(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_tRNS_SUPPORTED) else if (!png_memcmp(chunk_name, png_tRNS, 4)) png_handle_tRNS(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_zTXt_SUPPORTED) else if (!png_memcmp(chunk_name, png_zTXt, 4)) png_handle_zTXt(png_ptr, info_ptr, length); #endif #if defined(PNG_READ_iTXt_SUPPORTED) else if (!png_memcmp(chunk_name, png_iTXt, 4)) png_handle_iTXt(png_ptr, info_ptr, length); #endif else png_handle_unknown(png_ptr, info_ptr, length); } }