src/png/pngconf.h

   1
   2 /* pngconf.h - machine configurable file for libpng
   3  *
   4  * libpng version 1.5.7 - December 15, 2011
   5  *
   6  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
   7  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
   8  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
   9  *
  10  * This code is released under the libpng license.
  11  * For conditions of distribution and use, see the disclaimer
  12  * and license in png.h
  13  *
  14  */
  15
  16 /* Any machine specific code is near the front of this file, so if you
  17  * are configuring libpng for a machine, you may want to read the section
  18  * starting here down to where it starts to typedef png_color, png_text,
  19  * and png_info.
  20  */
  21
  22 #ifndef PNGCONF_H
  23 #define PNGCONF_H
  24
  25 #ifdef __DMC__
  26 #define PNG_NO_SNPRINTF
  27 #endif
  28
  29 #ifndef PNG_BUILDING_SYMBOL_TABLE
  30 /* PNG_NO_LIMITS_H may be used to turn off the use of the standard C
  31  * definition file for  machine specific limits, this may impact the
  32  * correctness of the definitons below (see uses of INT_MAX).
  33  */
  34 #  ifndef PNG_NO_LIMITS_H
  35 #    include <limits.h>
  36 #  endif
  37
  38 /* For the memory copy APIs (i.e. the standard definitions of these),
  39  * because this file defines png_memcpy and so on the base APIs must
  40  * be defined here.
  41  */
  42 #  ifdef BSD
  43 #    include <strings.h>
  44 #  else
  45 #    include <string.h>
  46 #  endif
  47
  48 /* For png_FILE_p - this provides the standard definition of a
  49  * FILE
  50  */
  51 #  ifdef PNG_STDIO_SUPPORTED
  52 #    include <stdio.h>
  53 #  endif
  54 #endif
  55
  56 /* This controls optimization of the reading of 16 and 32 bit values
  57  * from PNG files.  It can be set on a per-app-file basis - it
  58  * just changes whether a macro is used to the function is called.
  59  * The library builder sets the default, if read functions are not
  60  * built into the library the macro implementation is forced on.
  61  */
  62 #ifndef PNG_READ_INT_FUNCTIONS_SUPPORTED
  63 #  define PNG_USE_READ_MACROS
  64 #endif
  65 #if !defined(PNG_NO_USE_READ_MACROS) && !defined(PNG_USE_READ_MACROS)
  66 #  if PNG_DEFAULT_READ_MACROS
  67 #    define PNG_USE_READ_MACROS
  68 #  endif
  69 #endif
  70
  71 /* COMPILER SPECIFIC OPTIONS.
  72  *
  73  * These options are provided so that a variety of difficult compilers
  74  * can be used.  Some are fixed at build time (e.g. PNG_API_RULE
  75  * below) but still have compiler specific implementations, others
  76  * may be changed on a per-file basis when compiling against libpng.
  77  */
  78
  79 /* The PNGARG macro protects us against machines that don't have function
  80  * prototypes (ie K&R style headers).  If your compiler does not handle
  81  * function prototypes, define this macro and use the included ansi2knr.
  82  * I've always been able to use _NO_PROTO as the indicator, but you may
  83  * need to drag the empty declaration out in front of here, or change the
  84  * ifdef to suit your own needs.
  85  */
  86 #ifndef PNGARG
  87
  88 #  ifdef OF /* zlib prototype munger */
  89 #    define PNGARG(arglist) OF(arglist)
  90 #  else
  91
  92 #    ifdef _NO_PROTO
  93 #      define PNGARG(arglist) ()
  94 #    else
  95 #      define PNGARG(arglist) arglist
  96 #    endif /* _NO_PROTO */
  97
  98 #  endif /* OF */
  99
 100 #endif /* PNGARG */
 101
 102 /* Function calling conventions.
 103  * =============================
 104  * Normally it is not necessary to specify to the compiler how to call
 105  * a function - it just does it - however on x86 systems derived from
 106  * Microsoft and Borland C compilers ('IBM PC', 'DOS', 'Windows' systems
 107  * and some others) there are multiple ways to call a function and the
 108  * default can be changed on the compiler command line.  For this reason
 109  * libpng specifies the calling convention of every exported function and
 110  * every function called via a user supplied function pointer.  This is
 111  * done in this file by defining the following macros:
 112  *
 113  * PNGAPI    Calling convention for exported functions.
 114  * PNGCBAPI  Calling convention for user provided (callback) functions.
 115  * PNGCAPI   Calling convention used by the ANSI-C library (required
 116  *           for longjmp callbacks and sometimes used internally to
 117  *           specify the calling convention for zlib).
 118  *
 119  * These macros should never be overridden.  If it is necessary to
 120  * change calling convention in a private build this can be done
 121  * by setting PNG_API_RULE (which defaults to 0) to one of the values
 122  * below to select the correct 'API' variants.
 123  *
 124  * PNG_API_RULE=0 Use PNGCAPI - the 'C' calling convention - throughout.
 125  *                This is correct in every known environment.
 126  * PNG_API_RULE=1 Use the operating system convention for PNGAPI and
 127  *                the 'C' calling convention (from PNGCAPI) for
 128  *                callbacks (PNGCBAPI).  This is no longer required
 129  *                in any known environment - if it has to be used
 130  *                please post an explanation of the problem to the
 131  *                libpng mailing list.
 132  *
 133  * These cases only differ if the operating system does not use the C
 134  * calling convention, at present this just means the above cases
 135  * (x86 DOS/Windows sytems) and, even then, this does not apply to
 136  * Cygwin running on those systems.
 137  *
 138  * Note that the value must be defined in pnglibconf.h so that what
 139  * the application uses to call the library matches the conventions
 140  * set when building the library.
 141  */
 142
 143 /* Symbol export
 144  * =============
 145  * When building a shared library it is almost always necessary to tell
 146  * the compiler which symbols to export.  The png.h macro 'PNG_EXPORT'
 147  * is used to mark the symbols.  On some systems these symbols can be
 148  * extracted at link time and need no special processing by the compiler,
 149  * on other systems the symbols are flagged by the compiler and just
 150  * the declaration requires a special tag applied (unfortunately) in a
 151  * compiler dependent way.  Some systems can do either.
 152  *
 153  * A small number of older systems also require a symbol from a DLL to
 154  * be flagged to the program that calls it.  This is a problem because
 155  * we do not know in the header file included by application code that
 156  * the symbol will come from a shared library, as opposed to a statically
 157  * linked one.  For this reason the application must tell us by setting
 158  * the magic flag PNG_USE_DLL to turn on the special processing before
 159  * it includes png.h.
 160  *
 161  * Four additional macros are used to make this happen:
 162  *
 163  * PNG_IMPEXP The magic (if any) to cause a symbol to be exported from
 164  *            the build or imported if PNG_USE_DLL is set - compiler
 165  *            and system specific.
 166  *
 167  * PNG_EXPORT_TYPE(type) A macro that pre or appends PNG_IMPEXP to
 168  *                       'type', compiler specific.
 169  *
 170  * PNG_DLL_EXPORT Set to the magic to use during a libpng build to
 171  *                make a symbol exported from the DLL.  Not used in the
 172  *                public header files; see pngpriv.h for how it is used
 173  *                in the libpng build.
 174  *
 175  * PNG_DLL_IMPORT Set to the magic to force the libpng symbols to come
 176  *                from a DLL - used to define PNG_IMPEXP when
 177  *                PNG_USE_DLL is set.
 178  */
 179
 180 /* System specific discovery.
 181  * ==========================
 182  * This code is used at build time to find PNG_IMPEXP, the API settings
 183  * and PNG_EXPORT_TYPE(), it may also set a macro to indicate the DLL
 184  * import processing is possible.  On Windows/x86 systems it also sets
 185  * compiler-specific macros to the values required to change the calling
 186  * conventions of the various functions.
 187  */
 188 #if ( defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
 189       defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) ) &&\
 190     ( defined(_X86_) || defined(_X64_) || defined(_M_IX86) ||\
 191       defined(_M_X64) || defined(_M_IA64) )
 192   /* Windows system (DOS doesn't support DLLs) running on x86/x64.  Includes
 193    * builds under Cygwin or MinGW.  Also includes Watcom builds but these need
 194    * special treatment because they are not compatible with GCC or Visual C
 195    * because of different calling conventions.
 196    */
 197 #  if PNG_API_RULE == 2
 198     /* If this line results in an error, either because __watcall is not
 199      * understood or because of a redefine just below you cannot use *this*
 200      * build of the library with the compiler you are using.  *This* build was
 201      * build using Watcom and applications must also be built using Watcom!
 202      */
 203 #    define PNGCAPI __watcall
 204 #  endif
 205
 206 #  if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
 207 #    define PNGCAPI __cdecl
 208 #    if PNG_API_RULE == 1
 209 #      define PNGAPI __stdcall
 210 #    endif
 211 #  else
 212     /* An older compiler, or one not detected (erroneously) above,
 213      * if necessary override on the command line to get the correct
 214      * variants for the compiler.
 215      */
 216 #    ifndef PNGCAPI
 217 #      define PNGCAPI _cdecl
 218 #    endif
 219 #    if PNG_API_RULE == 1 && !defined(PNGAPI)
 220 #      define PNGAPI _stdcall
 221 #    endif
 222 #  endif /* compiler/api */
 223   /* NOTE: PNGCBAPI always defaults to PNGCAPI. */
 224
 225 #  if defined(PNGAPI) && !defined(PNG_USER_PRIVATEBUILD)
 226    ERROR: PNG_USER_PRIVATEBUILD must be defined if PNGAPI is changed
 227 #  endif
 228
 229 #  if (defined(_MSC_VER) && _MSC_VER < 800) ||\
 230       (defined(__BORLANDC__) && __BORLANDC__ < 0x500)
 231     /* older Borland and MSC
 232      * compilers used '__export' and required this to be after
 233      * the type.
 234      */
 235 #    ifndef PNG_EXPORT_TYPE
 236 #      define PNG_EXPORT_TYPE(type) type PNG_IMPEXP
 237 #    endif
 238 #    define PNG_DLL_EXPORT __export
 239 #  else /* newer compiler */
 240 #    define PNG_DLL_EXPORT __declspec(dllexport)
 241 #    ifndef PNG_DLL_IMPORT
 242 #      define PNG_DLL_IMPORT __declspec(dllimport)
 243 #    endif
 244 #  endif /* compiler */
 245
 246 #else /* !Windows/x86 */
 247 #  if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
 248 #    define PNGAPI _System
 249 #  else /* !Windows/x86 && !OS/2 */
 250     /* Use the defaults, or define PNG*API on the command line (but
 251      * this will have to be done for every compile!)
 252      */
 253 #  endif /* other system, !OS/2 */
 254 #endif /* !Windows/x86 */
 255
 256 /* Now do all the defaulting . */
 257 #ifndef PNGCAPI
 258 #  define PNGCAPI
 259 #endif
 260 #ifndef PNGCBAPI
 261 #  define PNGCBAPI PNGCAPI
 262 #endif
 263 #ifndef PNGAPI
 264 #  define PNGAPI PNGCAPI
 265 #endif
 266
 267 /* PNG_IMPEXP may be set on the compilation system command line or (if not set)
 268  * then in an internal header file when building the library, otherwise (when
 269  * using the library) it is set here.
 270  */
 271 #ifndef PNG_IMPEXP
 272 #  if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
 273      /* This forces use of a DLL, disallowing static linking */
 274 #    define PNG_IMPEXP PNG_DLL_IMPORT
 275 #  endif
 276
 277 #  ifndef PNG_IMPEXP
 278 #    define PNG_IMPEXP
 279 #  endif
 280 #endif
 281
 282 /* In 1.5.2 the definition of PNG_FUNCTION has been changed to always treat
 283  * 'attributes' as a storage class - the attributes go at the start of the
 284  * function definition, and attributes are always appended regardless of the
 285  * compiler.  This considerably simplifies these macros but may cause problems
 286  * if any compilers both need function attributes and fail to handle them as
 287  * a storage class (this is unlikely.)
 288  */
 289 #ifndef PNG_FUNCTION
 290 #  define PNG_FUNCTION(type, name, args, attributes) attributes type name args
 291 #endif
 292
 293 #ifndef PNG_EXPORT_TYPE
 294 #  define PNG_EXPORT_TYPE(type) PNG_IMPEXP type
 295 #endif
 296
 297    /* The ordinal value is only relevant when preprocessing png.h for symbol
 298     * table entries, so we discard it here.  See the .dfn files in the
 299     * scripts directory.
 300     */
 301 #ifndef PNG_EXPORTA
 302
 303 #  define PNG_EXPORTA(ordinal, type, name, args, attributes)\
 304       PNG_FUNCTION(PNG_EXPORT_TYPE(type),(PNGAPI name),PNGARG(args), \
 305         extern attributes)
 306 #endif
 307
 308 /* ANSI-C (C90) does not permit a macro to be invoked with an empty argument,
 309  * so make something non-empty to satisfy the requirement:
 310  */
 311 #define PNG_EMPTY /*empty list*/
 312
 313 #define PNG_EXPORT(ordinal, type, name, args)\
 314    PNG_EXPORTA(ordinal, type, name, args, PNG_EMPTY)
 315
 316 /* Use PNG_REMOVED to comment out a removed interface. */
 317 #ifndef PNG_REMOVED
 318 #  define PNG_REMOVED(ordinal, type, name, args, attributes)
 319 #endif
 320
 321 #ifndef PNG_CALLBACK
 322 #  define PNG_CALLBACK(type, name, args) type (PNGCBAPI name) PNGARG(args)
 323 #endif
 324
 325 /* Support for compiler specific function attributes.  These are used
 326  * so that where compiler support is available incorrect use of API
 327  * functions in png.h will generate compiler warnings.
 328  *
 329  * Added at libpng-1.2.41.
 330  */
 331
 332 #ifndef PNG_NO_PEDANTIC_WARNINGS
 333 #  ifndef PNG_PEDANTIC_WARNINGS_SUPPORTED
 334 #    define PNG_PEDANTIC_WARNINGS_SUPPORTED
 335 #  endif
 336 #endif
 337
 338 #ifdef PNG_PEDANTIC_WARNINGS_SUPPORTED
 339   /* Support for compiler specific function attributes.  These are used
 340    * so that where compiler support is available incorrect use of API
 341    * functions in png.h will generate compiler warnings.  Added at libpng
 342    * version 1.2.41.
 343    */
 344 #  if defined(__GNUC__)
 345 #    ifndef PNG_USE_RESULT
 346 #      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
 347 #    endif
 348 #    ifndef PNG_NORETURN
 349 #      define PNG_NORETURN   __attribute__((__noreturn__))
 350 #    endif
 351 #    ifndef PNG_ALLOCATED
 352 #      define PNG_ALLOCATED  __attribute__((__malloc__))
 353 #    endif
 354 #    ifndef PNG_DEPRECATED
 355 #      define PNG_DEPRECATED __attribute__((__deprecated__))
 356 #    endif
 357 #    ifndef PNG_PRIVATE
 358 #      if 0 /* Doesn't work so we use deprecated instead*/
 359 #        define PNG_PRIVATE \
 360           __attribute__((warning("This function is not exported by libpng.")))
 361 #      else
 362 #        define PNG_PRIVATE \
 363           __attribute__((__deprecated__))
 364 #      endif
 365 #    endif
 366 #  endif /* __GNUC__ */
 367
 368 #  if defined(_MSC_VER)  && (_MSC_VER >= 1300)
 369 #    ifndef PNG_USE_RESULT
 370 #      define PNG_USE_RESULT /* not supported */
 371 #    endif
 372 #    ifndef PNG_NORETURN
 373 #      define PNG_NORETURN __declspec(noreturn)
 374 #    endif
 375 #    ifndef PNG_ALLOCATED
 376 #      if (_MSC_VER >= 1400)
 377 #        define PNG_ALLOCATED __declspec(restrict)
 378 #      endif
 379 #    endif
 380 #    ifndef PNG_DEPRECATED
 381 #      define PNG_DEPRECATED __declspec(deprecated)
 382 #    endif
 383 #    ifndef PNG_PRIVATE
 384 #      define PNG_PRIVATE __declspec(deprecated)
 385 #    endif
 386 #  endif /* _MSC_VER */
 387 #endif /* PNG_PEDANTIC_WARNINGS */
 388
 389 #ifndef PNG_DEPRECATED
 390 #  define PNG_DEPRECATED  /* Use of this function is deprecated */
 391 #endif
 392 #ifndef PNG_USE_RESULT
 393 #  define PNG_USE_RESULT  /* The result of this function must be checked */
 394 #endif
 395 #ifndef PNG_NORETURN
 396 #  define PNG_NORETURN    /* This function does not return */
 397 #endif
 398 #ifndef PNG_ALLOCATED
 399 #  define PNG_ALLOCATED   /* The result of the function is new memory */
 400 #endif
 401 #ifndef PNG_PRIVATE
 402 #  define PNG_PRIVATE     /* This is a private libpng function */
 403 #endif
 404 #ifndef PNG_FP_EXPORT     /* A floating point API. */
 405 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 406 #     define PNG_FP_EXPORT(ordinal, type, name, args)\
 407          PNG_EXPORT(ordinal, type, name, args)
 408 #  else                   /* No floating point APIs */
 409 #     define PNG_FP_EXPORT(ordinal, type, name, args)
 410 #  endif
 411 #endif
 412 #ifndef PNG_FIXED_EXPORT  /* A fixed point API. */
 413 #  ifdef PNG_FIXED_POINT_SUPPORTED
 414 #     define PNG_FIXED_EXPORT(ordinal, type, name, args)\
 415          PNG_EXPORT(ordinal, type, name, args)
 416 #  else                   /* No fixed point APIs */
 417 #     define PNG_FIXED_EXPORT(ordinal, type, name, args)
 418 #  endif
 419 #endif
 420
 421 /* The following uses const char * instead of char * for error
 422  * and warning message functions, so some compilers won't complain.
 423  * If you do not want to use const, define PNG_NO_CONST here.
 424  *
 425  * This should not change how the APIs are called, so it can be done
 426  * on a per-file basis in the application.
 427  */
 428 #ifndef PNG_CONST
 429 #  ifndef PNG_NO_CONST
 430 #    define PNG_CONST const
 431 #  else
 432 #    define PNG_CONST
 433 #  endif
 434 #endif
 435
 436 /* Some typedefs to get us started.  These should be safe on most of the
 437  * common platforms.  The typedefs should be at least as large as the
 438  * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
 439  * don't have to be exactly that size.  Some compilers dislike passing
 440  * unsigned shorts as function parameters, so you may be better off using
 441  * unsigned int for png_uint_16.
 442  */
 443
 444 #if defined(INT_MAX) && (INT_MAX > 0x7ffffffeL)
 445 typedef unsigned int png_uint_32;
 446 typedef int png_int_32;
 447 #else
 448 typedef unsigned long png_uint_32;
 449 typedef long png_int_32;
 450 #endif
 451 typedef unsigned short png_uint_16;
 452 typedef short png_int_16;
 453 typedef unsigned char png_byte;
 454
 455 #ifdef PNG_NO_SIZE_T
 456 typedef unsigned int png_size_t;
 457 #else
 458 typedef size_t png_size_t;
 459 #endif
 460 #define png_sizeof(x) (sizeof (x))
 461
 462 /* The following is needed for medium model support.  It cannot be in the
 463  * pngpriv.h header.  Needs modification for other compilers besides
 464  * MSC.  Model independent support declares all arrays and pointers to be
 465  * large using the far keyword.  The zlib version used must also support
 466  * model independent data.  As of version zlib 1.0.4, the necessary changes
 467  * have been made in zlib.  The USE_FAR_KEYWORD define triggers other
 468  * changes that are needed. (Tim Wegner)
 469  */
 470
 471 /* Separate compiler dependencies (problem here is that zlib.h always
 472  * defines FAR. (SJT)
 473  */
 474 #ifdef __BORLANDC__
 475 #  if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
 476 #    define LDATA 1
 477 #  else
 478 #    define LDATA 0
 479 #  endif
 480   /* GRR:  why is Cygwin in here?  Cygwin is not Borland C... */
 481 #  if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__)
 482 #    define PNG_MAX_MALLOC_64K /* only used in build */
 483 #    if (LDATA != 1)
 484 #      ifndef FAR
 485 #        define FAR __far
 486 #      endif
 487 #      define USE_FAR_KEYWORD
 488 #    endif   /* LDATA != 1 */
 489          /* Possibly useful for moving data out of default segment.
 490           * Uncomment it if you want. Could also define FARDATA as
 491           * const if your compiler supports it. (SJT)
 492 #        define FARDATA FAR
 493           */
 494 #  endif  /* __WIN32__, __FLAT__, __CYGWIN__ */
 495 #endif   /* __BORLANDC__ */
 496
 497
 498 /* Suggest testing for specific compiler first before testing for
 499  * FAR.  The Watcom compiler defines both __MEDIUM__ and M_I86MM,
 500  * making reliance oncertain keywords suspect. (SJT)
 501  */
 502
 503 /* MSC Medium model */
 504 #ifdef FAR
 505 #  ifdef M_I86MM
 506 #    define USE_FAR_KEYWORD
 507 #    define FARDATA FAR
 508 #    include <dos.h>
 509 #  endif
 510 #endif
 511
 512 /* SJT: default case */
 513 #ifndef FAR
 514 #  define FAR
 515 #endif
 516
 517 /* At this point FAR is always defined */
 518 #ifndef FARDATA
 519 #  define FARDATA
 520 #endif
 521
 522 /* Typedef for floating-point numbers that are converted
 523  * to fixed-point with a multiple of 100,000, e.g., gamma
 524  */
 525 typedef png_int_32 png_fixed_point;
 526
 527 /* Add typedefs for pointers */
 528 typedef void                      FAR * png_voidp;
 529 typedef PNG_CONST void            FAR * png_const_voidp;
 530 typedef png_byte                  FAR * png_bytep;
 531 typedef PNG_CONST png_byte        FAR * png_const_bytep;
 532 typedef png_uint_32               FAR * png_uint_32p;
 533 typedef PNG_CONST png_uint_32     FAR * png_const_uint_32p;
 534 typedef png_int_32                FAR * png_int_32p;
 535 typedef PNG_CONST png_int_32      FAR * png_const_int_32p;
 536 typedef png_uint_16               FAR * png_uint_16p;
 537 typedef PNG_CONST png_uint_16     FAR * png_const_uint_16p;
 538 typedef png_int_16                FAR * png_int_16p;
 539 typedef PNG_CONST png_int_16      FAR * png_const_int_16p;
 540 typedef char                      FAR * png_charp;
 541 typedef PNG_CONST char            FAR * png_const_charp;
 542 typedef png_fixed_point           FAR * png_fixed_point_p;
 543 typedef PNG_CONST png_fixed_point FAR * png_const_fixed_point_p;
 544 typedef png_size_t                FAR * png_size_tp;
 545 typedef PNG_CONST png_size_t      FAR * png_const_size_tp;
 546
 547 #ifdef PNG_STDIO_SUPPORTED
 548 typedef FILE            * png_FILE_p;
 549 #endif
 550
 551 #ifdef PNG_FLOATING_POINT_SUPPORTED
 552 typedef double           FAR * png_doublep;
 553 typedef PNG_CONST double FAR * png_const_doublep;
 554 #endif
 555
 556 /* Pointers to pointers; i.e. arrays */
 557 typedef png_byte        FAR * FAR * png_bytepp;
 558 typedef png_uint_32     FAR * FAR * png_uint_32pp;
 559 typedef png_int_32      FAR * FAR * png_int_32pp;
 560 typedef png_uint_16     FAR * FAR * png_uint_16pp;
 561 typedef png_int_16      FAR * FAR * png_int_16pp;
 562 typedef PNG_CONST char  FAR * FAR * png_const_charpp;
 563 typedef char            FAR * FAR * png_charpp;
 564 typedef png_fixed_point FAR * FAR * png_fixed_point_pp;
 565 #ifdef PNG_FLOATING_POINT_SUPPORTED
 566 typedef double          FAR * FAR * png_doublepp;
 567 #endif
 568
 569 /* Pointers to pointers to pointers; i.e., pointer to array */
 570 typedef char            FAR * FAR * FAR * png_charppp;
 571
 572 /* png_alloc_size_t is guaranteed to be no smaller than png_size_t,
 573  * and no smaller than png_uint_32.  Casts from png_size_t or png_uint_32
 574  * to png_alloc_size_t are not necessary; in fact, it is recommended
 575  * not to use them at all so that the compiler can complain when something
 576  * turns out to be problematic.
 577  * Casts in the other direction (from png_alloc_size_t to png_size_t or
 578  * png_uint_32) should be explicitly applied; however, we do not expect
 579  * to encounter practical situations that require such conversions.
 580  */
 581 #if defined(__TURBOC__) && !defined(__FLAT__)
 582    typedef unsigned long png_alloc_size_t;
 583 #else
 584 #  if defined(_MSC_VER) && defined(MAXSEG_64K)
 585      typedef unsigned long    png_alloc_size_t;
 586 #  else
 587      /* This is an attempt to detect an old Windows system where (int) is
 588       * actually 16 bits, in that case png_malloc must have an argument with a
 589       * bigger size to accomodate the requirements of the library.
 590       */
 591 #    if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) && \
 592         (!defined(INT_MAX) || INT_MAX <= 0x7ffffffeL)
 593        typedef DWORD         png_alloc_size_t;
 594 #    else
 595        typedef png_size_t    png_alloc_size_t;
 596 #    endif
 597 #  endif
 598 #endif
 599
 600 #endif /* PNGCONF_H */