jpeg/jinclude.h

   1 /*
   2  * jinclude.h
   3  *
   4  * Copyright (C) 1991-1994, Thomas G. Lane.
   5  * This file is part of the Independent JPEG Group's software.
   6  * For conditions of distribution and use, see the accompanying README file.
   7  *
   8  * This file exists to provide a single place to fix any problems with
   9  * including the wrong system include files.  (Common problems are taken
  10  * care of by the standard jconfig symbols, but on really weird systems
  11  * you may have to edit this file.)
  12  *
  13  * NOTE: this file is NOT intended to be included by applications using the
  14  * JPEG library.  Most applications need only include jpeglib.h.
  15  */
  16
  17
  18 /* Include auto-config file to find out which system include files we need. */
  19
  20 #include "jconfig.h"            /* auto configuration options */
  21 #define JCONFIG_INCLUDED        /* so that jpeglib.h doesn't do it again */
  22
  23 /*
  24  * We need the NULL macro and size_t typedef.
  25  * On an ANSI-conforming system it is sufficient to include <stddef.h>.
  26  * Otherwise, we get them from <stdlib.h> or <stdio.h>; we may have to
  27  * pull in <sys/types.h> as well.
  28  * Note that the core JPEG library does not require <stdio.h>;
  29  * only the default error handler and data source/destination modules do.
  30  * But we must pull it in because of the references to FILE in jpeglib.h.
  31  * You can remove those references if you want to compile without <stdio.h>.
  32  */
  33
  34 #ifdef HAVE_STDDEF_H
  35 #include <stddef.h>
  36 #endif
  37
  38 #ifdef HAVE_STDLIB_H
  39 #include <stdlib.h>
  40 #endif
  41
  42 #ifdef NEED_SYS_TYPES_H
  43 #include <sys/types.h>
  44 #endif
  45
  46 #include <stdio.h>
  47
  48 /*
  49  * We need memory copying and zeroing functions, plus strncpy().
  50  * ANSI and System V implementations declare these in <string.h>.
  51  * BSD doesn't have the mem() functions, but it does have bcopy()/bzero().
  52  * Some systems may declare memset and memcpy in <memory.h>.
  53  *
  54  * NOTE: we assume the size parameters to these functions are of type size_t.
  55  * Change the casts in these macros if not!
  56  */
  57
  58 #ifdef NEED_BSD_STRINGS
  59
  60 #include <strings.h>
  61 #define MEMZERO(target,size)    bzero((void *)(target), (size_t)(size))
  62 #define MEMCOPY(dest,src,size)  bcopy((const void *)(src), (void *)(dest), (size_t)(size))
  63
  64 #else /* not BSD, assume ANSI/SysV string lib */
  65
  66 #include <string.h>
  67 #define MEMZERO(target,size)    memset((void *)(target), 0, (size_t)(size))
  68 #define MEMCOPY(dest,src,size)  memcpy((void *)(dest), (const void *)(src), (size_t)(size))
  69
  70 #endif
  71
  72 /*
  73  * In ANSI C, and indeed any rational implementation, size_t is also the
  74  * type returned by sizeof().  However, it seems there are some irrational
  75  * implementations out there, in which sizeof() returns an int even though
  76  * size_t is defined as long or unsigned long.  To ensure consistent results
  77  * we always use this SIZEOF() macro in place of using sizeof() directly.
  78  */
  79
  80 #define SIZEOF(object)  ((size_t) sizeof(object))
  81
  82 /*
  83  * The modules that use fread() and fwrite() always invoke them through
  84  * these macros.  On some systems you may need to twiddle the argument casts.
  85  * CAUTION: argument order is different from underlying functions!
  86  */
  87
  88 #define JFREAD(file,buf,sizeofbuf)  \
  89   ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
  90 #define JFWRITE(file,buf,sizeofbuf)  \
  91   ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))