jinclude.h

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/*
 * jinclude.h
 *
 * Copyright (C) 1991-1994, Thomas G. Lane.
 * This file is part of the Independent JPEG Group's software.
 * For conditions of distribution and use, see the accompanying README file.
 *
 * This file exists to provide a single place to fix any problems with
 * including the wrong system include files.  (Common problems are taken
 * care of by the standard jconfig symbols, but on really weird systems
 * you may have to edit this file.)
 *
 * NOTE: this file is NOT intended to be included by applications using the
 * JPEG library.  Most applications need only include jpeglib.h.
 */
 
 
/* Include auto-config file to find out which system include files we need. */
 
#ifndef __jinclude_h__
#define __jinclude_h__
 
#include "jconfig.h"            /* auto configuration options */
#define JCONFIG_INCLUDED        /* so that jpeglib.h doesn't do it again */
 
/*
 * We need the NULL macro and size_t typedef.
 * On an ANSI-conforming system it is sufficient to include <stddef.h>.
 * Otherwise, we get them from <stdlib.h> or <stdio.h>; we may have to
 * pull in <sys/types.h> as well.
 * Note that the core JPEG library does not require <stdio.h>;
 * only the default error handler and data source/destination modules do.
 * But we must pull it in because of the references to FILE in jpeglib.h.
 * You can remove those references if you want to compile without <stdio.h>.
 */
 
#ifdef HAVE_STDDEF_H
#include <stddef.h>
#endif
 
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
 
#ifdef NEED_SYS_TYPES_H
#include <sys/types.h>
#endif
 
#include <stdio.h>
 
/*
 * We need memory copying and zeroing functions, plus strncpy().
 * ANSI and System V implementations declare these in <string.h>.
 * BSD doesn't have the mem() functions, but it does have bcopy()/bzero().
 * Some systems may declare memset and memcpy in <memory.h>.
 *
 * NOTE: we assume the size parameters to these functions are of type size_t.
 * Change the casts in these macros if not!
 */
 
#ifdef NEED_BSD_STRINGS
 
#include <strings.h>
#define MEMZERO(target,size)    bzero((void *)(target), (size_t)(size))
#define MEMCOPY(dest,src,size)  bcopy((const void *)(src), (void *)(dest), (size_t)(size))
 
#else /* not BSD, assume ANSI/SysV string lib */
 
#include <string.h>
#define MEMZERO(target,size)    memset((void *)(target), 0, (size_t)(size))
#define MEMCOPY(dest,src,size)  memcpy((void *)(dest), (const void *)(src), (size_t)(size))
 
#endif
 
/*
 * In ANSI C, and indeed any rational implementation, size_t is also the
 * type returned by sizeof().  However, it seems there are some irrational
 * implementations out there, in which sizeof() returns an int even though
 * size_t is defined as long or unsigned long.  To ensure consistent results
 * we always use this SIZEOF() macro in place of using sizeof() directly.
 */
 
#define SIZEOF(object)  ((size_t) sizeof(object))
 
/*
 * The modules that use fread() and fwrite() always invoke them through
 * these macros.  On some systems you may need to twiddle the argument casts.
 * CAUTION: argument order is different from underlying functions!
 */
 
#define JFREAD(file,buf,sizeofbuf)  \
  ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
#define JFWRITE(file,buf,sizeofbuf)  \
  ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))
 
 
 
typedef enum {                  /* JPEG marker codes */
  M_SOF0  = 0xc0,
  M_SOF1  = 0xc1,
  M_SOF2  = 0xc2,
  M_SOF3  = 0xc3,
 
  M_SOF5  = 0xc5,
  M_SOF6  = 0xc6,
  M_SOF7  = 0xc7,
 
  M_JPG   = 0xc8,
  M_SOF9  = 0xc9,
  M_SOF10 = 0xca,
  M_SOF11 = 0xcb,
 
  M_SOF13 = 0xcd,
  M_SOF14 = 0xce,
  M_SOF15 = 0xcf,
 
  M_DHT   = 0xc4,
 
  M_DAC   = 0xcc,
 
  M_RST0  = 0xd0,
  M_RST1  = 0xd1,
  M_RST2  = 0xd2,
  M_RST3  = 0xd3,
  M_RST4  = 0xd4,
  M_RST5  = 0xd5,
  M_RST6  = 0xd6,
  M_RST7  = 0xd7,
 
  M_SOI   = 0xd8,
  M_EOI   = 0xd9,
  M_SOS   = 0xda,
  M_DQT   = 0xdb,
  M_DNL   = 0xdc,
  M_DRI   = 0xdd,
  M_DHP   = 0xde,
  M_EXP   = 0xdf,
 
  M_APP0  = 0xe0,
  M_APP1  = 0xe1,
  M_APP2  = 0xe2,
  M_APP3  = 0xe3,
  M_APP4  = 0xe4,
  M_APP5  = 0xe5,
  M_APP6  = 0xe6,
  M_APP7  = 0xe7,
  M_APP8  = 0xe8,
  M_APP9  = 0xe9,
  M_APP10 = 0xea,
  M_APP11 = 0xeb,
  M_APP12 = 0xec,
  M_APP13 = 0xed,
  M_APP14 = 0xee,
  M_APP15 = 0xef,
 
  M_JPG0  = 0xf0,
  M_JPG13 = 0xfd,
  M_COM   = 0xfe,
 
  M_TEM   = 0x01,
 
  M_ERROR = 0x100
} JPEG_MARKER;
 
 
/*
 * Figure F.12: extend sign bit.
 * On some machines, a shift and add will be faster than a table lookup.
 */
 
#ifdef AVOID_TABLES
 
#define HUFF_EXTEND(x,s)  ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))
 
#else
 
#define HUFF_EXTEND(x,s)  ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))
 
static const int extend_test[16] =   /* entry n is 2**(n-1) */
  { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
    0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };
 
#define SHIFTED_BITS_PLUS_ONE(n) (int) (((unsigned int) -1) << n) + 1
 
static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
  { 0,
    SHIFTED_BITS_PLUS_ONE (1), SHIFTED_BITS_PLUS_ONE (2), SHIFTED_BITS_PLUS_ONE (3), SHIFTED_BITS_PLUS_ONE (4),
    SHIFTED_BITS_PLUS_ONE (5), SHIFTED_BITS_PLUS_ONE (6), SHIFTED_BITS_PLUS_ONE (7), SHIFTED_BITS_PLUS_ONE (8),
    SHIFTED_BITS_PLUS_ONE (9), SHIFTED_BITS_PLUS_ONE (10), SHIFTED_BITS_PLUS_ONE (11), SHIFTED_BITS_PLUS_ONE (12),
    SHIFTED_BITS_PLUS_ONE (13), SHIFTED_BITS_PLUS_ONE (14), SHIFTED_BITS_PLUS_ONE (15) };
 
#undef SHIFTED_BITS_PLUS_ONE
 
#endif /* AVOID_TABLES */
 
 
#endif