修改iconv源代码，使其支持【JIS X0208保留领域13区】的转码---最终代码

/*
*Windows的机种依存文字 PC-9800系列等，NEC的电脑在日本主流的时候曾独自被定义了文字13区分配。
**/
static const unsigned short jisx0208_2uni_page2D[96] = {
/* 0x2D20 - 0x2D2F */
0xfffd, 0x2460, 0x2461, 0x2462, 0x2463, 0x2464, 0x2465, 0x2466,
0x2467,	0x2468, 0x2469, 0x246A, 0x246B, 0x246C, 0x246D, 0x246E,
/* 0x2D30 - 0x2D3F */
0x246F,	0x2470, 0x2471, 0x2472, 0x2473, 0x2160, 0x2161, 0x2162,
0x2163,	0x2164,	0x2165, 0x2166, 0x2167, 0x2168, 0x2169, 0xfffd,
/* 0x2D40 - 0x2D4F */
0x3349, 0x3314,	0x3322, 0x334D, 0x3318, 0x3327, 0x3303, 0x3336,
0x3351,	0x3357,	0x330D, 0x3326, 0x3323, 0x332B, 0x334A, 0x333B,
/* 0x2D50 - 0x2D5F */
0x339C, 0x339D, 0x339E, 0x338E, 0x338F, 0x33C4, 0x33A1, 0xfffd,
0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0xfffd, 0x337B,
/* 0x2D60 - 0x2D6F */
0x301D, 0x301F, 0x2116, 0x33CD, 0x2121, 0x32A4, 0x32A5, 0x32A6,
0x32A7, 0x32A8, 0x3231, 0x3232, 0x3239, 0x337E, 0x337D, 0x337C,
/* 0x2D70 - 0x2D7F */
0x2252, 0x2261, 0x222B, 0x222E, 0x2211, 0x221A, 0x22A5, 0x2220,
0x221F, 0x22BF, 0x2235, 0x2229, 0x222A, 0xfffd, 0xfffd, 0xfffd
};

static int
jisx0208_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
{
unsigned char c1 = s[0];

/* 增加jp 对 [Windows的机种依存文字] 解码的支持*/
if (c1 == 0x2D)
{
if (n >= 2)
{
unsigned char c2 = s[1];
if (c2 >= 0x20 && c2 < 0x7F) {
unsigned int i = (c2 - 0x20);
unsigned short wc = jisx0208_2uni_page2D[i];
*pwc = (ucs4_t) wc;
return 2;
}
return RET_ILSEQ;
}
return RET_TOOFEW(0);
}
/* end */

if ((c1 >= 0x21 && c1 <= 0x28) || (c1 >= 0x30 && c1 <= 0x74)) {
if (n >= 2) {
unsigned char c2 = s[1];
if (c2 >= 0x21 && c2 < 0x7f) {
unsigned int i = 94 * (c1 - 0x21) + (c2 - 0x21);
unsigned short wc = 0xfffd;
if (i < 1410) {
if (i < 690)
wc = jisx0208_2uni_page21[i];
} else {
if (i < 7808)
wc = jisx0208_2uni_page30[i-1410];
}
if (wc != 0xfffd) {
*pwc = (ucs4_t) wc;
return 2;
}
}
return RET_ILSEQ;
}
return RET_TOOFEW(0);
}
return RET_ILSEQ;
}