cliproto.h

一个不错的fastdb使用例子

//-< CLIPROTO.H >----------------------------------------------------*--------*
// FastDB                    Version 1.0         (c) 1999  GARRET    *     ?  *
// (Main Memory Database Management System)                          *   /\|  *
//                                                                   *  /  \  *
//                          Created:     13-Jan-2000  K.A. Knizhnik  * / [] \ *
//                          Last update: 13-Jan-2000  K.A. Knizhnik  * GARRET *
//-------------------------------------------------------------------*--------*
// Client-server communication protocol
//-------------------------------------------------------------------*--------*

#ifndef __CLIPROTO_H__
#define __CLIPROTO_H__

enum cli_commands {
  cli_cmd_close_session,
  cli_cmd_prepare_and_execute,
  cli_cmd_execute,
  cli_cmd_get_first,
  cli_cmd_get_last,
  cli_cmd_get_next,
  cli_cmd_get_prev,
  cli_cmd_free_statement,
  cli_cmd_abort,
  cli_cmd_commit,
  cli_cmd_update,
  cli_cmd_remove,
  cli_cmd_insert,
  cli_cmd_prepare_and_insert,
  cli_cmd_describe_table,
  cli_cmd_show_tables,
  cli_cmd_precommit,
  cli_cmd_skip,
  cli_cmd_create_table,
  cli_cmd_drop_table,
  cli_cmd_alter_index,
  cli_cmd_freeze,
  cli_cmd_unfreeze,
  cli_cmd_seek,
  cli_cmd_alter_table,
  cli_cmd_last
};

static const int sizeof_type[] =
  {
    sizeof(cli_oid_t),
    sizeof(cli_bool_t),
    sizeof(cli_int1_t),
    sizeof(cli_int2_t),
    sizeof(cli_int4_t),
    sizeof(cli_int8_t),
    sizeof(cli_real4_t),
    sizeof(cli_real8_t),
    0, // cli_decimal
    0, // cli_asciiz,
    0, // cli_pasciiz,
    0, // cli_cstring,
    0, // cli_array_of_oid,
    0, // cli_array_of_bool,
    0, // cli_array_of_int1,
    0, // cli_array_of_int2,
    0, // cli_array_of_int4,
    0, // cli_array_of_int8,
    0, // cli_array_of_real4,
    0, // cli_array_of_real8,
    0, // cli_array_of_decimal,
    0, // cli_array_of_string,
    0, // cli_any,
    0, // cli_datetime,
    4, // cli_autoincrement,
    0, // cli_rectangle,
    0  // cli_unknown
  };

static const int fd2cli_type_mapping[] =
  {
    cli_bool,
    cli_int1,
    cli_int2,
    cli_int4,
    cli_int8,
    cli_real4,
    cli_real8,
    cli_asciiz,
    cli_oid
  };

#if defined(__FreeBSD__)
#include <sys/param.h>
#include <netinet/in.h>
#define USE_HTON_NTOH
#elif defined(__linux__)
//
// At Linux inline assembly declarations of ntohl, htonl... are available
//
#include <netinet/in.h>
#define USE_HTON_NTOH
#else
#if defined(_WIN32) && _M_IX86 >= 400
#pragma warning(disable:4035) // disable "no return" warning
#ifdef __BORLANDC__
static
#else
inline
#endif
int swap_bytes_in_dword(int val)
{
  __asm {
    mov eax, val
    bswap eax
  }
}

#ifdef __BORLANDC__
static
#else
inline
#endif
short swap_bytes_in_word(short val)
{
  __asm {
    mov ax, val
    xchg al,ah
  }
}

#pragma warning(default:4035)
#define ntohl(w) swap_bytes_in_dword(w)
#define htonl(w) swap_bytes_in_dword(w)
#define ntohs(w) swap_bytes_in_word(w)
#define htons(w) swap_bytes_in_word(w)

#define USE_HTON_NTOH
#endif
#endif




inline char* pack2(char* dst, int2 val)
{
  *dst++ = char(val >> 8);
  *dst++ = char(val);
  return dst;
}

inline char* pack2(char* dst, char* src)
{
  return pack2(dst, *(int2*)src);
}

inline void pack2(int2& val)
{
#if BYTE_ORDER != BIG_ENDIAN
#ifdef USE_HTON_NTOH
  val = htons(val);
#else

  pack2((char*)&val, val);
#endif
#endif
}


inline char* pack4(char* dst, int4 val)
{
  *dst++ = char(val >> 24);
  *dst++ = char(val >> 16);
  *dst++ = char(val >> 8);
  *dst++ = char(val);
  return dst;
}

inline char* pack4(char* dst, char* src)
{
  return pack4(dst, *(int4*)src);
}

inline void pack4(int4& val)
{
#if BYTE_ORDER != BIG_ENDIAN
#ifdef USE_HTON_NTOH
  val = htonl(val);
#else

  pack4((char*)&val, val);
#endif
#endif
}


inline char* pack8(char* dst, char* src)
{
#if BYTE_ORDER == BIG_ENDIAN
  return pack4( pack4(dst, src), src + 4);
#else

  return pack4( pack4(dst, src + 4), src);
#endif
}

inline char* pack8(char* dst, db_int8 val)
{
  return pack8(dst, (char*)&val);
}

inline char* pack_oid(char* dst, cli_oid_t oid)
{
  return (sizeof(oid) == 4) ? pack4(dst, oid) : pack8(dst, (char*)&oid);
}

inline int2 unpack2(char* src)
{
  nat1* s = (nat1*)src;
  return (s[0] << 8) + s[1];
}

inline char* unpack2(char* dst, char* src)
{
  *(int2*)dst = unpack2(src);
  return src + 2;
}

inline void  unpack2(int2& val)
{
#if BYTE_ORDER != BIG_ENDIAN
#ifdef USE_HTON_NTOH
  val = ntohs(val);
#else

  val = unpack2((char*)&val);
#endif
#endif
}


inline int4  unpack4(char* src)
{
  nat1* s = (nat1*)src;
  return (((((s[0] << 8) + s[1]) << 8) + s[2]) << 8) + s[3];
}

inline char* unpack4(char* dst, char* src)
{
  *(int4*)dst = unpack4(src);
  return src + 4;
}

inline void unpack4(int4& val)
{
#if BYTE_ORDER != BIG_ENDIAN
#ifdef USE_HTON_NTOH
  val = ntohl(val);
#else

  val = unpack4((char*)&val);
#endif
#endif
}

inline char* unpack8(char* dst, char* src)
{
#if BYTE_ORDER == BIG_ENDIAN
  *(int4*)dst = unpack4(src);
  *((int4*)dst+1) = unpack4(src+4);
#else

  *(int4*)dst = unpack4(src+4);
  *((int4*)dst+1) = unpack4(src);
#endif

  return src + 8;
}

inline db_int8 unpack8(char* src)
{
  db_int8 val;
  unpack8((char*)&val, src);
  return val;
}

inline cli_oid_t unpack_oid(char* src)
{
  cli_oid_t oid;

  if (sizeof(oid) == 4)
  {
    oid = unpack4(src);
  }
  else
  {
    unpack8((char*)&oid, src);
  }

  return oid;
}

struct cli_request
{
  int4 length;
  int4 cmd;
  int4 stmt_id;

  void pack()
  {
    pack4(length);
    pack4(cmd);
    pack4(stmt_id);
  }

  void unpack()
  {
    unpack4(length);
    unpack4(cmd);
    unpack4(stmt_id);
  }
};

#endif