Subversion Repositories SvarDOS

/*!\file sys/swap.h

 * Swapping of short/long values.

 */

#ifndef __SYS_SWAP_BYTES_H

#define __SYS_SWAP_BYTES_H

#ifndef __SYS_W32API_H

#include <sys/w32api.h>

#endif

#ifndef __SYS_CDEFS_H

#include <sys/cdefs.h>

#endif

#ifndef __NETINET_IN_H

#include <netinet/in.h>

#endif

#if defined(__dj_include_netinet_in_h_)

#error "You are using the wrong version of <netinet/in.h>. Ref. point 10 of the INSTALL file"

#endif

__BEGIN_DECLS

#if defined(WIN32) || defined(_WIN32) /* provide some real versions too */

  W32_FUNC unsigned short W32_CALL ntohs (unsigned short);

  W32_FUNC unsigned short W32_CALL htons (unsigned short);

  W32_FUNC unsigned long  W32_CALL ntohl (unsigned long);

  W32_FUNC unsigned long  W32_CALL htonl (unsigned long);

  W32_FUNC unsigned long  cdecl   _w32_intel   (unsigned long x);

  W32_FUNC unsigned short cdecl   _w32_intel16 (unsigned short x);

#endif

#undef  ntohs

#undef  htons

#undef  ntohl

#undef  htonl

#define ntohs(x)  intel16(x)

#define htons(x)  intel16(x)

#define ntohl(x)  intel(x)

#define htonl(x)  intel(x)

/*

 * Hard to believe, but someone uses Watt-32 on a

 * Motorola/PowerPC embedded target.

 */

#if defined(BIG_ENDIAN_MACHINE) || defined(USE_BIGENDIAN)

  #define intel(x)    x

  #define intel16(x)  x

#elif defined(__GNUC__) && !defined(__NO_INLINE__)  /* -O0 */

  #define intel(x)   __ntohl(x)

  #define intel16(x) __ntohs(x)

  /*

   * Ripped (and adapted) from <linux/include/asm-386/byteorder.h>

   */

  /*@unused@*/ extern __inline__ unsigned long __ntohl (unsigned long x)

  {

    __asm__ __volatile (

             "xchgb %b0, %h0\n\t"   /* swap lower bytes  */

             "rorl  $16, %0\n\t"    /* swap words        */

             "xchgb %b0, %h0"       /* swap higher bytes */

            : "=q" (x) : "0" (x));

    return (x);

  }

  /*@unused@*/ extern __inline__ unsigned short __ntohs (unsigned short x)

  {

    __asm__ __volatile__ (

              "xchgb %b0, %h0"       /* swap bytes */

            : "=q" (x) : "0" (x));

    return (x);

  }

#elif defined(__POCC__)             /* PellesC */

  #define intel(x)   __ntohl(x)

  #define intel16(x) __ntohs(x)

  __declspec(naked) inline unsigned long __fastcall __ntohl (unsigned long x)

  {

    __asm xchg cl, ch    /* 'x' is in ecx */

    __asm ror  ecx, 16

    __asm xchg cl, ch

    __asm mov  eax, ecx

    __asm ret

  }

  __declspec(naked) inline unsigned short __fastcall __ntohs (unsigned short x)

  {

    __asm xchg  cl, ch    /* 'x' is in ecx */

    __asm movzx eax, cx

    __asm ret

  }

#elif (defined(_MSC_VER) && (_MSC_VER >= 1200)) &&  /* MSVC 6+ */ \

      !defined(__POCC__)           /* "pocc -Ze" sets _MSC_VER */

  #define intel(x)   __ntohl(x)

  #define intel16(x) __ntohs(x)

  __declspec(naked) static unsigned long __ntohl (unsigned long x)

  {

    __asm mov  eax, [esp+4]

    __asm xchg al, ah

    __asm ror  eax, 16

    __asm xchg al, ah

    __asm ret

  }

  __declspec(naked) static unsigned short __ntohs (unsigned short x)

  {

    __asm mov  ax, [esp+4]

    __asm xchg al, ah

    __asm ret

  }

#elif defined(__WATCOMC__) && defined(__FLAT__)  /* Watcom 32-bit */

  #define intel(x)   __ntohl(x)

  #define intel16(x) __ntohs(x)

  extern unsigned long __ntohl (unsigned long x);

  #pragma aux  __ntohl =     \

              "xchg al, ah"  \

              "ror  eax, 16" \

              "xchg al, ah"  \

              parm   [eax]   \

              modify [eax];

  extern unsigned short __ntohs (unsigned short x);

  #pragma aux __ntohs =     \

              "xchg al, ah" \

              parm   [ax]   \

              modify [ax];

#elif defined(__WATCOMC__) && !defined(__FLAT__)  /* Watcom 16-bit */

  #define intel(x)   __ntohl(x)

  #define intel16(x) __ntohs(x)

  extern unsigned long __ntohl (unsigned long x);

  #pragma aux  __ntohl =     \

              "xchg al, dh"  \

              "xchg ah, dl"  \

              parm   [dx ax] \

              modify [dx ax];

  extern unsigned short __ntohs (unsigned short x);

  #pragma aux __ntohs =     \

              "xchg al, ah" \

              parm   [ax]   \

              modify [ax];

#elif (defined(__BORLANDC__) && defined(__FLAT__)) || /* bcc32 */ \

      (defined(__DMC__) && (__INTSIZE==4))            /* dmc -mx */

  #include <dos.h>

  #define intel(x)    __ntohl(x)

  #define intel16(x)  __ntohs(x)

  #define __ntohs(x)  (_AX = x, \

                       __emit__(0x86,0xC4),      /* xchg al, ah */ \

                       _AX)

  #define __ntohl(x)  (_EAX = x, \

                       __emit__(0x86,0xC4),      /* xchg al, ah  */ \

                       __emit__(0xC1,0xC8,0x10), /* ror  eax, 16 */ \

                       __emit__(0x86,0xC4),      /* xchg al, ah  */ \

                       _EAX)

#elif defined(__CCDL__) && defined(__386__)      /* LadSoft 386 */

  #define intel(x)    __ntohl(x)

  #define intel16(x)  __ntohs(x)

  static unsigned long __ntohl (unsigned long x)

  {

    asm { mov  eax, [x]

          xchg al, ah

          ror  eax, 16

          xchg al, ah

        }

    return (_EAX);

  }

  static unsigned short __ntohs (unsigned short x)

  {

    asm { mov  ax, [x]

          xchg al, ah

        }

    return (unsigned short)_EAX;  /* doesn't have _AX */

  }

  /* This crashes mysteriously if we use _bswap()

   */

#elif defined(__LCC__) && 0              /* LCC-Win32 */

  #define intel(x)    __ntohl(x)

  #define intel16(x)  __ntohs(x)

  #if 0

    #include <intrinsics.h>

    #define W32_LCC_INTRINSICS_INCLUDED  /* header guard is missing */

    #define __ntohl(x)   (unsigned long) _bswap(x)

    #define __ntohs(x)  ((unsigned short) (_bswap(x) >> 16))

  #else

    unsigned long inline __declspec(naked) __ntohl (unsigned long x)

    {

      _asm ("movl (%esp), %eax");

      _asm ("xchg %ah, %al");

      _asm ("rorl $16, %eax");

      _asm ("xchg %ah, %al");

    }

    unsigned short inline __declspec(naked) __ntohs (unsigned short x)

    {

      _asm ("movs (%esp), %ax");

      _asm ("xchg %ah, %al");

    }

  #endif

#else  /* no inlining possible (or worth the effort) */

  #define intel   W32_NAMESPACE (intel)

  #define intel16 W32_NAMESPACE (intel16)

  #define WATT_NO_INLINE_INTEL

  W32_FUNC unsigned long  cdecl intel   (unsigned long x);

  W32_FUNC unsigned short cdecl intel16 (unsigned short x);

#endif

__END_DECLS

#endif /* __SYS_SWAP_BYTES_H */