components/iconv/gb2312_to_ucs2.c

   1 /**************************************************************************
   2  *              Copyright (C), AirM2M Tech. Co., Ltd.
   3  *
   4  * Name:    gb2312_to_ucs2.c
   5  * Author:  liweiqiang
   6  * Version: V0.1
   7  * Date:    2013/11/26
   8  *
   9  * Description:
  10  *          gb2312 ×ª»» ucs2
  11  **************************************************************************/
  12 #include <stdint.h>
  13 #include "stdio.h"
  14 #include "errno.h"
  15
  16 #include "gb2312_to_ucs2_table.h"
  17
  18 uint16_t gb2312_to_ucs(uint16_t gb2312)
  19 {
  20     uint16_t ucs;
  21     uint8_t gb = gb2312;
  22
  23     if (gb < 0x80)
  24     {
  25         ucs = gb;
  26     }
  27     else
  28     {
  29         uint16_t offset = ((gb2312 >> 8) - 0xA0) * 94 + ((gb2312 & 0x00ff) - 0xA1);
  30         ucs = gb2312_to_ucs2_table[offset];
  31     }
  32
  33     return ucs;
  34 }
  35
  36 size_t iconv_gb2312_to_ucs2_endian(char **_inbuf, size_t *inbytesleft, char **_outbuf, size_t *outbytesleft, int endian)
  37 {
  38     uint16_t offset,gb2312;
  39     char *gbbuf = *_inbuf;
  40     uint16_t *ucs2buf = (uint16_t*)*_outbuf;
  41     uint16_t ucs2;
  42     size_t ucs2len = 0;
  43     size_t inlen = *inbytesleft;
  44     size_t outlen = *outbytesleft;
  45     size_t ret = 0;
  46
  47     while(inlen > 0)
  48     {
  49         if(ucs2len+2 > outlen)
  50         {
  51             errno = E2BIG;
  52             ret = -1;
  53             goto gb2312_to_ucs2_exit;
  54         }
  55
  56         gb2312 = *gbbuf++;
  57
  58         if(gb2312 < 0x80)
  59         {
  60             ucs2 = gb2312;
  61             inlen--;
  62         }
  63         else if(inlen >= 2)
  64         {
  65             gb2312 = (gb2312<<8) + ((*gbbuf++)&0x00ff);
  66             inlen -= 2;
  67
  68             offset = ((gb2312>>8) - 0xA0)*94/*(0xFE-0xA1+1)*/ + ((gb2312&0x00ff) - 0xA1);
  69             ucs2 = gb2312_to_ucs2_table[offset];
  70         }
  71         else
  72         {
  73             break;
  74         }
  75
  76         if(endian == 1)
  77             ucs2 = (ucs2<<8)|(ucs2>>8);
  78
  79         *ucs2buf++ = ucs2;
  80         ucs2len += 2;
  81     }
  82
  83     if(inlen > 0)
  84     {
  85         errno = EINVAL;
  86         ret = -1;
  87     }
  88
  89 gb2312_to_ucs2_exit:
  90     *_inbuf = gbbuf;
  91
  92     *inbytesleft = inlen;
  93     *outbytesleft -= ucs2len;
  94
  95     return ret;
  96 }
  97
  98 size_t iconv_gb2312_to_ucs2(char **_inbuf, size_t *inbytesleft, char **_outbuf, size_t *outbytesleft)
  99 {
 100     return iconv_gb2312_to_ucs2_endian(_inbuf, inbytesleft, _outbuf, outbytesleft, 0);
 101 }
 102
 103 size_t iconv_gb2312_to_ucs2be(char **_inbuf, size_t *inbytesleft, char **_outbuf, size_t *outbytesleft)
 104 {
 105     return iconv_gb2312_to_ucs2_endian(_inbuf, inbytesleft, _outbuf, outbytesleft, 1);
 106 }