text: /*
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  /* pngstruct.h - header file for PNG reference library
   *
   * This file is available under and governed by the GNU General Public
   * License version 2 only, as published by the Free Software Foundation.
   * However, the following notice accompanied the original version of this
   * file and, per its terms, should not be removed:
   *
   * Last changed in libpng 1.6.32 [August 24, 2017]
   * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
   * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
   * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
   *
   * This code is released under the libpng license.
   * For conditions of distribution and use, see the disclaimer
   * and license in png.h
   */
  
  /* The structure that holds the information to read and write PNG files.
   * The only people who need to care about what is inside of this are the
   * people who will be modifying the library for their own special needs.
   * It should NOT be accessed directly by an application.
   */
  
  #ifndef PNGSTRUCT_H
  #define PNGSTRUCT_H
  /* zlib.h defines the structure z_stream, an instance of which is included
   * in this structure and is required for decompressing the LZ compressed
   * data in PNG files.
   */
  #ifndef ZLIB_CONST
     /* We must ensure that zlib uses 'const' in declarations. */
  #  define ZLIB_CONST
  #endif
  #include "zlib.h"
  #ifdef const
     /* zlib.h sometimes #defines const to nothing, undo this. */
  #  undef const
  #endif
  
  /* zlib.h has mediocre z_const use before 1.2.6, this stuff is for compatibility
   * with older builds.
   */
  #if ZLIB_VERNUM < 0x1260
  #  define PNGZ_MSG_CAST(s) png_constcast(char*,s)
  #  define PNGZ_INPUT_CAST(b) png_constcast(png_bytep,b)
  #else
  #  define PNGZ_MSG_CAST(s) (s)
  #  define PNGZ_INPUT_CAST(b) (b)
  #endif
  
  /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
   * can handle at once.  This type need be no larger than 16 bits (so maximum of
   * 65535), this define allows us to discover how big it is, but limited by the
   * maximuum for png_size_t.  The value can be overriden in a library build
   * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
   * lower value (e.g. 255 works).  A lower value may help memory usage (slightly)
   * and may even improve performance on some systems (and degrade it on others.)
   */
  #ifndef ZLIB_IO_MAX
  #  define ZLIB_IO_MAX ((uInt)-1)
  #endif
  
  #ifdef PNG_WRITE_SUPPORTED
  /* The type of a compression buffer list used by the write code. */
  typedef struct png_compression_buffer
  {
     struct png_compression_buffer *next;
     png_byte                       output[1]; /* actually zbuf_size */
  } png_compression_buffer, *png_compression_bufferp;
  
  #define PNG_COMPRESSION_BUFFER_SIZE(pp)\
     (offsetof(png_compression_buffer, output) + (pp)->zbuffer_size)
  #endif
  
  /* Colorspace support; structures used in png_struct, png_info and in internal
   * functions to hold and communicate information about the color space.
   *
   * PNG_COLORSPACE_SUPPORTED is only required if the application will perform
   * colorspace corrections, otherwise all the colorspace information can be
   * skipped and the size of libpng can be reduced (significantly) by compiling
   * out the colorspace support.
   */
  #ifdef PNG_COLORSPACE_SUPPORTED
  /* The chromaticities of the red, green and blue colorants and the chromaticity
   * of the corresponding white point (i.e. of rgb(1.0,1.0,1.0)).
   */
  typedef struct png_xy
  {
     png_fixed_point redx, redy;
     png_fixed_point greenx, greeny;
     png_fixed_point bluex, bluey;
     png_fixed_point whitex, whitey;
  } png_xy;
  
  /* The same data as above but encoded as CIE XYZ values.  When this data comes
   * from chromaticities the sum of the Y values is assumed to be 1.0
   */
  typedef struct png_XYZ
  {
     png_fixed_point red_X, red_Y, red_Z;
     png_fixed_point green_X, green_Y, green_Z;
     png_fixed_point blue_X, blue_Y, blue_Z;
  } png_XYZ;
  #endif /* COLORSPACE */
  
  #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
  /* A colorspace is all the above plus, potentially, profile information;
   * however at present libpng does not use the profile internally so it is only
   * stored in the png_info struct (if iCCP is supported.)  The rendering intent
   * is retained here and is checked.
   *
   * The file gamma encoding information is also stored here and gamma correction
   * is done by libpng, whereas color correction must currently be done by the
   * application.
   */
  typedef struct png_colorspace
  {
  #ifdef PNG_GAMMA_SUPPORTED
     png_fixed_point gamma;        /* File gamma */
  #endif
  
  #ifdef PNG_COLORSPACE_SUPPORTED
     png_xy      end_points_xy;    /* End points as chromaticities */
     png_XYZ     end_points_XYZ;   /* End points as CIE XYZ colorant values */
     png_uint_16 rendering_intent; /* Rendering intent of a profile */
  #endif
  
     /* Flags are always defined to simplify the code. */
     png_uint_16 flags;            /* As defined below */
  } png_colorspace, * PNG_RESTRICT png_colorspacerp;
  
  typedef const png_colorspace * PNG_RESTRICT png_const_colorspacerp;
  
  /* General flags for the 'flags' field */
  #define PNG_COLORSPACE_HAVE_GAMMA           0x0001
  #define PNG_COLORSPACE_HAVE_ENDPOINTS       0x0002
  #define PNG_COLORSPACE_HAVE_INTENT          0x0004
  #define PNG_COLORSPACE_FROM_gAMA            0x0008
  #define PNG_COLORSPACE_FROM_cHRM            0x0010
  #define PNG_COLORSPACE_FROM_sRGB            0x0020
  #define PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB 0x0040
  #define PNG_COLORSPACE_MATCHES_sRGB         0x0080 /* exact match on profile */
  #define PNG_COLORSPACE_INVALID              0x8000
  #define PNG_COLORSPACE_CANCEL(flags)        (0xffff ^ (flags))
  #endif /* COLORSPACE || GAMMA */
  
  struct png_struct_def
  {
  #ifdef PNG_SETJMP_SUPPORTED
     jmp_buf jmp_buf_local;     /* New name in 1.6.0 for jmp_buf in png_struct */
     png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
     jmp_buf *jmp_buf_ptr;      /* passed to longjmp_fn */
     size_t jmp_buf_size;       /* size of the above, if allocated */
  #endif
     png_error_ptr error_fn;    /* function for printing errors and aborting */
  #ifdef PNG_WARNINGS_SUPPORTED
     png_error_ptr warning_fn;  /* function for printing warnings */
  #endif
     png_voidp error_ptr;       /* user supplied struct for error functions */
     png_rw_ptr write_data_fn;  /* function for writing output data */
     png_rw_ptr read_data_fn;   /* function for reading input data */
     png_voidp io_ptr;          /* ptr to application struct for I/O functions */
  
  #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
     png_user_transform_ptr read_user_transform_fn; /* user read transform */
  #endif
  
  #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
     png_user_transform_ptr write_user_transform_fn; /* user write transform */
  #endif
  
  /* These were added in libpng-1.0.2 */
  #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
  #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
      defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
     png_voidp user_transform_ptr; /* user supplied struct for user transform */
     png_byte user_transform_depth;    /* bit depth of user transformed pixels */
     png_byte user_transform_channels; /* channels in user transformed pixels */
  #endif
  #endif
  
     png_uint_32 mode;          /* tells us where we are in the PNG file */
     png_uint_32 flags;         /* flags indicating various things to libpng */
     png_uint_32 transformations; /* which transformations to perform */
  
     png_uint_32 zowner;        /* ID (chunk type) of zstream owner, 0 if none */
     z_stream    zstream;       /* decompression structure */
  
  #ifdef PNG_WRITE_SUPPORTED
     png_compression_bufferp zbuffer_list; /* Created on demand during write */
     uInt                    zbuffer_size; /* size of the actual buffer */
  
     int zlib_level;            /* holds zlib compression level */
     int zlib_method;           /* holds zlib compression method */
     int zlib_window_bits;      /* holds zlib compression window bits */
     int zlib_mem_level;        /* holds zlib compression memory level */
     int zlib_strategy;         /* holds zlib compression strategy */
  #endif
  /* Added at libpng 1.5.4 */
  #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
     int zlib_text_level;            /* holds zlib compression level */
     int zlib_text_method;           /* holds zlib compression method */
     int zlib_text_window_bits;      /* holds zlib compression window bits */
     int zlib_text_mem_level;        /* holds zlib compression memory level */
     int zlib_text_strategy;         /* holds zlib compression strategy */
  #endif
  /* End of material added at libpng 1.5.4 */
  /* Added at libpng 1.6.0 */
  #ifdef PNG_WRITE_SUPPORTED
     int zlib_set_level;        /* Actual values set into the zstream on write */
     int zlib_set_method;
     int zlib_set_window_bits;
     int zlib_set_mem_level;
     int zlib_set_strategy;
  #endif
  
     png_uint_32 width;         /* width of image in pixels */
     png_uint_32 height;        /* height of image in pixels */
     png_uint_32 num_rows;      /* number of rows in current pass */
     png_uint_32 usr_width;     /* width of row at start of write */
     png_size_t rowbytes;       /* size of row in bytes */
     png_uint_32 iwidth;        /* width of current interlaced row in pixels */
     png_uint_32 row_number;    /* current row in interlace pass */
     png_uint_32 chunk_name;    /* PNG_CHUNK() id of current chunk */
     png_bytep prev_row;        /* buffer to save previous (unfiltered) row.
                                 * While reading this is a pointer into
                                 * big_prev_row; while writing it is separately
                                 * allocated if needed.
                                 */
     png_bytep row_buf;         /* buffer to save current (unfiltered) row.
                                 * While reading, this is a pointer into
                                 * big_row_buf; while writing it is separately
                                 * allocated.
                                 */
  #ifdef PNG_WRITE_FILTER_SUPPORTED
     png_bytep try_row;    /* buffer to save trial row when filtering */
     png_bytep tst_row;    /* buffer to save best trial row when filtering */
  #endif
     png_size_t info_rowbytes;  /* Added in 1.5.4: cache of updated row bytes */
  
     png_uint_32 idat_size;     /* current IDAT size for read */
     png_uint_32 crc;           /* current chunk CRC value */
     png_colorp palette;        /* palette from the input file */
     png_uint_16 num_palette;   /* number of color entries in palette */
  
  /* Added at libpng-1.5.10 */
  #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
     int num_palette_max;       /* maximum palette index found in IDAT */
  #endif
  
     png_uint_16 num_trans;     /* number of transparency values */
     png_byte compression;      /* file compression type (always 0) */
     png_byte filter;           /* file filter type (always 0) */
     png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
     png_byte pass;             /* current interlace pass (0 - 6) */
     png_byte do_filter;        /* row filter flags (see PNG_FILTER_ in png.h ) */
     png_byte color_type;       /* color type of file */
     png_byte bit_depth;        /* bit depth of file */
     png_byte usr_bit_depth;    /* bit depth of users row: write only */
     png_byte pixel_depth;      /* number of bits per pixel */
     png_byte channels;         /* number of channels in file */
  #ifdef PNG_WRITE_SUPPORTED
     png_byte usr_channels;     /* channels at start of write: write only */
  #endif
     png_byte sig_bytes;        /* magic bytes read/written from start of file */
     png_byte maximum_pixel_depth;
                                /* pixel depth used for the row buffers */
     png_byte transformed_pixel_depth;
                                /* pixel depth after read/write transforms */
  #if ZLIB_VERNUM >= 0x1240
     png_byte zstream_start;    /* at start of an input zlib stream */
  #endif /* Zlib >= 1.2.4 */
  #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
     png_uint_16 filler;           /* filler bytes for pixel expansion */
  #endif
  
  #if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
     defined(PNG_READ_ALPHA_MODE_SUPPORTED)
     png_byte background_gamma_type;
     png_fixed_point background_gamma;
     png_color_16 background;   /* background color in screen gamma space */
  #ifdef PNG_READ_GAMMA_SUPPORTED
     png_color_16 background_1; /* background normalized to gamma 1.0 */
  #endif
  #endif /* bKGD */
  
  #ifdef PNG_WRITE_FLUSH_SUPPORTED
     png_flush_ptr output_flush_fn; /* Function for flushing output */
     png_uint_32 flush_dist;    /* how many rows apart to flush, 0 - no flush */
     png_uint_32 flush_rows;    /* number of rows written since last flush */
  #endif
  
  #ifdef PNG_READ_GAMMA_SUPPORTED
     int gamma_shift;      /* number of "insignificant" bits in 16-bit gamma */
     png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
  
     png_bytep gamma_table;     /* gamma table for 8-bit depth files */
     png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
  #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
     defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
     defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
     png_bytep gamma_from_1;    /* converts from 1.0 to screen */
     png_bytep gamma_to_1;      /* converts from file to 1.0 */
     png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
     png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
  #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
  #endif
  
  #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
     png_color_8 sig_bit;       /* significant bits in each available channel */
  #endif
  
  #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
     png_color_8 shift;         /* shift for significant bit tranformation */
  #endif
  
  #if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
   || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
     png_bytep trans_alpha;           /* alpha values for paletted files */
     png_color_16 trans_color;  /* transparent color for non-paletted files */
  #endif
  
     png_read_status_ptr read_row_fn;   /* called after each row is decoded */
     png_write_status_ptr write_row_fn; /* called after each row is encoded */
  #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
     png_progressive_info_ptr info_fn; /* called after header data fully read */
     png_progressive_row_ptr row_fn;   /* called after a prog. row is decoded */
     png_progressive_end_ptr end_fn;   /* called after image is complete */
     png_bytep save_buffer_ptr;        /* current location in save_buffer */
     png_bytep save_buffer;            /* buffer for previously read data */
     png_bytep current_buffer_ptr;     /* current location in current_buffer */
     png_bytep current_buffer;         /* buffer for recently used data */
     png_uint_32 push_length;          /* size of current input chunk */
     png_uint_32 skip_length;          /* bytes to skip in input data */
     png_size_t save_buffer_size;      /* amount of data now in save_buffer */
     png_size_t save_buffer_max;       /* total size of save_buffer */
     png_size_t buffer_size;           /* total amount of available input data */
     png_size_t current_buffer_size;   /* amount of data now in current_buffer */
     int process_mode;                 /* what push library is currently doing */
     int cur_palette;                  /* current push library palette index */
  
  #endif /* PROGRESSIVE_READ */
  
  #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
  /* For the Borland special 64K segment handler */
     png_bytepp offset_table_ptr;
     png_bytep offset_table;
     png_uint_16 offset_table_number;
     png_uint_16 offset_table_count;
     png_uint_16 offset_table_count_free;
  #endif
  
  #ifdef PNG_READ_QUANTIZE_SUPPORTED
     png_bytep palette_lookup; /* lookup table for quantizing */
     png_bytep quantize_index; /* index translation for palette files */
  #endif
  
  /* Options */
  #ifdef PNG_SET_OPTION_SUPPORTED
     png_uint_32 options;           /* On/off state (up to 16 options) */
  #endif
  
  #if PNG_LIBPNG_VER < 10700
  /* To do: remove this from libpng-1.7 */
  #ifdef PNG_TIME_RFC1123_SUPPORTED
     char time_buffer[29]; /* String to hold RFC 1123 time text */
  #endif
  #endif
  
  /* New members added in libpng-1.0.6 */
  
     png_uint_32 free_me;    /* flags items libpng is responsible for freeing */
  
  #ifdef PNG_USER_CHUNKS_SUPPORTED
     png_voidp user_chunk_ptr;
  #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
     png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
  #endif
  #endif
  
  #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
     int          unknown_default; /* As PNG_HANDLE_* */
     unsigned int num_chunk_list;  /* Number of entries in the list */
     png_bytep    chunk_list;      /* List of png_byte[5]; the textual chunk name
                                    * followed by a PNG_HANDLE_* byte */
  #endif
  
  /* New members added in libpng-1.0.3 */
  #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
     png_byte rgb_to_gray_status;
     /* Added in libpng 1.5.5 to record setting of coefficients: */
     png_byte rgb_to_gray_coefficients_set;
     /* These were changed from png_byte in libpng-1.0.6 */
     png_uint_16 rgb_to_gray_red_coeff;
     png_uint_16 rgb_to_gray_green_coeff;
     /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */
  #endif
  
  /* New member added in libpng-1.0.4 (renamed in 1.0.9) */
  #if defined(PNG_MNG_FEATURES_SUPPORTED)
  /* Changed from png_byte to png_uint_32 at version 1.2.0 */
     png_uint_32 mng_features_permitted;
  #endif
  
  /* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
  #ifdef PNG_MNG_FEATURES_SUPPORTED
     png_byte filter_type;
  #endif
  
  /* New members added in libpng-1.2.0 */
  
  /* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
  #ifdef PNG_USER_MEM_SUPPORTED
     png_voidp mem_ptr;             /* user supplied struct for mem functions */
     png_malloc_ptr malloc_fn;      /* function for allocating memory */
     png_free_ptr free_fn;          /* function for freeing memory */
  #endif
  
  /* New member added in libpng-1.0.13 and 1.2.0 */
     png_bytep big_row_buf;         /* buffer to save current (unfiltered) row */
  
  #ifdef PNG_READ_QUANTIZE_SUPPORTED
  /* The following three members were added at version 1.0.14 and 1.2.4 */
     png_bytep quantize_sort;          /* working sort array */
     png_bytep index_to_palette;       /* where the original index currently is
                                          in the palette */
     png_bytep palette_to_index;       /* which original index points to this
                                           palette color */
  #endif
  
  /* New members added in libpng-1.0.16 and 1.2.6 */
     png_byte compression_type;
  
  #ifdef PNG_USER_LIMITS_SUPPORTED
     png_uint_32 user_width_max;
     png_uint_32 user_height_max;
  
     /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
      * chunks that can be stored (0 means unlimited).
      */
     png_uint_32 user_chunk_cache_max;
  
     /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk
      * can occupy when decompressed.  0 means unlimited.
      */
     png_alloc_size_t user_chunk_malloc_max;
  #endif
  
  /* New member added in libpng-1.0.25 and 1.2.17 */
  #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
     /* Temporary storage for unknown chunk that the library doesn't recognize,
      * used while reading the chunk.
      */
     png_unknown_chunk unknown_chunk;
  #endif
  
  /* New member added in libpng-1.2.26 */
    png_size_t old_big_row_buf_size;
  
  #ifdef PNG_READ_SUPPORTED
  /* New member added in libpng-1.2.30 */
    png_bytep        read_buffer;      /* buffer for reading chunk data */
    png_alloc_size_t read_buffer_size; /* current size of the buffer */
  #endif
  #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
    uInt             IDAT_read_size;   /* limit on read buffer size for IDAT */
  #endif
  
  #ifdef PNG_IO_STATE_SUPPORTED
  /* New member added in libpng-1.4.0 */
     png_uint_32 io_state;
  #endif
  
  /* New member added in libpng-1.5.6 */
     png_bytep big_prev_row;
  
  /* New member added in libpng-1.5.7 */
     void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
        png_bytep row, png_const_bytep prev_row);
  
  #ifdef PNG_READ_SUPPORTED
  #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
     png_colorspace   colorspace;
  #endif
  #endif
  };
  #endif /* PNGSTRUCT_H */
  