tctoeuc.c

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	tctoeuc.c (libtcstr)
 *
 *	W	tctoeuc(UB *euc, TC tc)
 *
 *	Convert a TC character into an EUC character and store it in euc.
 *	Return the number of converted bytes (1 or 2) as a function value.
 *	If euc == NULL, do not store the conversion result, but return a correct function value.
 *	If the character cannot be converted, return the function value "-1"; if tc == TNULL, return the function value "0".
 */

#include <basic.h>
#include <tstring.h>
#include <tcode.h>


#define TSD_TEU_VAL_32		32
#define TSD_TEU_VAL_128		128
#define TSD_TEU_SFT_8		8
#define TSD_TEU_RTN_2		2
#define TSD_TEU_RTN_M1		(-1)
#define TSD_TEU_MSK_0X8080	(TC)0x8080
#define TSD_TEU_VAL_0X80	(TC)0x80
#define TSD_TEU_MAX_0X23FF	(TC)0x23ff

EXPORT	W	tctoeuc( UB *euc, TC tc )
{
	W	c;

	if (tc == TNULL) {
		return 0;
	}
	if ((tc & TSD_TEU_MSK_0X8080) != (TC)0) {
		return TSD_TEU_RTN_M1;
	}

	if ((tc < TSD_TEU_VAL_0X80) != 0) {
		if (euc != 0) {
			*euc = (UB)tc;
		}
		return 1;
	}

	if ((tc >= TK_KSP )&&( tc < TSD_TEU_MAX_0X23FF)) {
		for (c = TSD_TEU_VAL_32; c < TSD_TEU_VAL_128; c++) {
			if (_asctotc[c] == tc) {
				if (euc != 0) {
					*euc = (UB)c;
				}
				return 1;
			}
		}
	}
	if (euc != 0) {
		tc |= TSD_TEU_MSK_0X8080;
		*(euc++) = (UB)(tc >> (TC)TSD_TEU_SFT_8);
		*euc = (UB)tc;
	}
	return	TSD_TEU_RTN_2;
}