libsndfile/src/sfendian.h

   1 /*
   2 ** Copyright (C) 1999-2003 Erik de Castro Lopo <erikd@zip.com.au>
   3 **
   4 ** This program is free software; you can redistribute it and/or modify
   5 ** it under the terms of the GNU Lesser General Public License as published by
   6 ** the Free Software Foundation; either version 2.1 of the License, or
   7 ** (at your option) any later version.
   8 **
   9 ** This program is distributed in the hope that it will be useful,
  10 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 ** GNU Lesser General Public License for more details.
  13 **
  14 ** You should have received a copy of the GNU Lesser General Public License
  15 ** along with this program; if not, write to the Free Software
  16 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17 */
  18
  19 #include        "config.h"
  20
  21 /*
  22 ** Many file types (ie WAV, AIFF) use sets of four consecutive bytes as a
  23 ** marker indicating different sections of the file.
  24 ** The following MAKE_MARKER macro allows th creation of integer constants
  25 ** for these markers.
  26 */
  27
  28 #if (CPU_IS_LITTLE_ENDIAN == 1)
  29         #define MAKE_MARKER(a,b,c,d)    ((a)|((b)<<8)|((c)<<16)|((d)<<24))
  30 #elif (CPU_IS_BIG_ENDIAN == 1)
  31         #define MAKE_MARKER(a,b,c,d)    (((a)<<24)|((b)<<16)|((c)<<8)|(d))
  32 #else
  33         #error "Target CPU endian-ness unknown. May need to hand edit src/config.h"
  34 #endif
  35
  36 /* wo standard endswap macros. */
  37
  38 #define ENDSWAP_SHORT(x)        ((((x)>>8)&0xFF)+(((x)&0xFF)<<8))
  39 #define ENDSWAP_INT(x)          ((((x)>>24)&0xFF)+(((x)>>8)&0xFF00)+(((x)&0xFF00)<<8)+(((x)&0xFF)<<24))
  40 /*
  41 ** Macros to handle reading of data of a specific endian-ness into host endian
  42 ** shorts and ints. The single input is an unsigned char* pointer to the start
  43 ** of the object. There are two versions of each macro as we need to deal with
  44 ** both big and little endian CPUs.
  45 */
  46
  47 #if (CPU_IS_LITTLE_ENDIAN == 1)
  48         #define LES2H_SHORT(x)                  (x)
  49         #define LEI2H_INT(x)                    (x)
  50
  51         #define LES2H_SHORT_PTR(x)              (((short*) x) [0])
  52         #define LES2H_INT_PTR(x)                ((((short*) x) [0]) << 16)
  53
  54         #define LET2H_SHORT_PTR(x)              ((x) [1] + ((x) [2] << 8))
  55         #define LET2H_INT_PTR(x)                (((x) [0] << 8) + ((x) [1] << 16) + ((x) [2] << 24))
  56
  57         #define LEI2H_SHORT_PTR(x)              ((((int*) x) [0]) >> 16)
  58         #define LEI2H_INT_PTR(x)                (((int*) x) [0])
  59
  60         #define BES2H_SHORT(x)                  ENDSWAP_SHORT(x)
  61         #define BEI2H_INT(x)                    ENDSWAP_INT(x)
  62
  63         #define BES2H_SHORT_PTR(x)              (((x) [0] << 8) + (x) [1])
  64         #define BES2H_INT_PTR(x)                (((x) [0] << 24) + ((x) [1] << 16))
  65
  66         #define BET2H_SHORT_PTR(x)              (((x) [0] << 8) + (x) [1])
  67         #define BET2H_INT_PTR(x)                (((x) [0] << 24) + ((x) [1] << 16) + ((x) [2] << 8))
  68
  69         #define BEI2H_SHORT_PTR(x)              (((x) [0] << 8) + (x) [1])
  70         #define BEI2H_INT_PTR(x)                (((x) [0] << 24) + ((x) [1] << 16) + ((x) [2] << 8) + (x) [3])
  71
  72 #elif (CPU_IS_BIG_ENDIAN == 1)
  73         #define LES2H_SHORT(x)                  ENDSWAP_SHORT(x)
  74         #define LEI2H_INT(x)                    ENDSWAP_INT(x)
  75
  76         #define LES2H_SHORT_PTR(x)              ((x) [0] + ((x) [1] << 8))
  77         #define LES2H_INT_PTR(x)                (((x) [0] << 16) + ((x) [1] << 24))
  78
  79         #define LET2H_SHORT_PTR(x)              ((x) [1] + ((x) [2] << 8))
  80         #define LET2H_INT_PTR(x)                (((x) [0] << 8) + ((x) [1] << 16) + ((x) [2] << 24))
  81
  82         #define LEI2H_SHORT_PTR(x)              ((x) [2] + ((x) [3] << 8))
  83         #define LEI2H_INT_PTR(x)                ((x) [0] + ((x) [1] << 8) + ((x) [2] << 16) + ((x) [3] << 24))
  84
  85         #define BES2H_SHORT(x)                  (x)
  86         #define BEI2H_INT(x)                    (x)
  87
  88         #define BES2H_SHORT_PTR(x)              (((short*) x) [0])
  89         #define BES2H_INT_PTR(x)                ((((short*) x) [0]) << 16)
  90
  91         #define BET2H_SHORT_PTR(x)              (((x) [0] << 8) + (x) [1])
  92         #define BET2H_INT_PTR(x)                (((x) [0] << 24) + ((x) [1] << 16) + ((x) [2] << 8))
  93
  94         #define BEI2H_SHORT_PTR(x)              ((((int*) x) [0]) >> 16)
  95         #define BEI2H_INT_PTR(x)                (((int*) x) [0])
  96
  97 #else
  98         #error "Target CPU endian-ness unknown. May need to hand edit src/config.h"
  99 #endif
 100
 101 /* Endian swapping routines implemented in sfendian.c. */
 102
 103 void    endswap_short_array     (short *ptr, int len) ;
 104 void    endswap_int_array       (int *ptr, int len) ;
 105
 106 /* Always swaps 8 byte values whether sizeof (long) == 8 or not. */
 107 void    endswap_long_array  (long *ptr, int len) ;
 108
 109 void    endswap_short_copy      (short *dest, short *src, int len) ;
 110 void    endswap_int_copy        (int *dest, int *src, int len) ;
 111
 112 /* Always swaps 8 byte values whether sizeof (long) == 8 or not. */
 113 void    endswap_long_copy  (long *dest, long *src, int len) ;
 114