wchar.c

它通过提供glibc兼容使得应用程序移植到较小的c 库时相当得容易. 它能够应用到带虚拟存储的Linux和uClinux上.在大多数带MMU部件的平台上为使它更加紧凑,它也能够编译成共享库.uClib

	assert(swc != NULL);

	while (wn && t) {
		wc = *swc;

		*s = wc;
		len = 1;

		if (wc >= 0x80) {
#ifdef KUHN
			if (
#if UTF_8_MAX_LEN == 3
				/* For plane 0, these are the only defined values.*/
				/* Note that we don't need to worry about exceeding */
				/* 31 bits as that is the most that UTF-8 provides. */
				(wc > 0xfffdU)
#else
				/* UTF_8_MAX_LEN == 6 */
				(wc > 0x7fffffffUL)
				|| ( ((__uwchar_t)(wc - 0xfffeU)) < 2)
#endif
				|| ( ((__uwchar_t)(wc - 0xd800U)) < (0xe000U - 0xd800U) )
				) {
				return (size_t) -1;
			}
#else  /* KUHN */
#if UTF_8_MAX_LEN != 3
			if (wc > 0x7fffffffUL) { /* Value too large. */
				return (size_t) -1;
			}
#endif
#endif /* KUHN */

			wc >>= 1;
			p = s;
			do {
				++p;
			} while (wc >>= 5);
			wc = *swc;
			if ((len = p - s) > t) { /* Not enough space. */
				break;
			}

			m = 0x80;
			while( p>s ) {
				m = (m >> 1) | 0x80;
				*--p = (wc & 0x3f) | 0x80;
				wc >>= 6;
			}
			*s |= (m << 1);
		} else if (wc == 0) {	/* End of string. */
			swc = NULL;
			break;
		}

		++swc;
		--wn;
		t -= len;
		if (store) {
			s += len;
		}
	}

	if (store) {
		*src = (const wchar_t *) swc;
	}

	return n - t;
}


#endif
/**********************************************************************/
#ifdef L___mbsnrtowcs

/* WARNING: We treat len as SIZE_MAX when dst is NULL! */

size_t mbsnrtowcs(wchar_t *__restrict dst, const char **__restrict src,
				  size_t NMC, size_t len, mbstate_t *__restrict ps)
	 __attribute__ ((__weak__, __alias__("__mbsnrtowcs")));

size_t __mbsnrtowcs(wchar_t *__restrict dst, const char **__restrict src,
					size_t NMC, size_t len, mbstate_t *__restrict ps)
{
	static mbstate_t mbstate;	/* Rely on bss 0-init. */
	wchar_t wcbuf[1];
	const char *s;
	size_t count;
	int incr;

	if (!ps) {
		ps = &mbstate;
	}

#ifdef __CTYPE_HAS_UTF_8_LOCALES
	if (ENCODING == __ctype_encoding_utf8) {
		size_t r;
		return ((r = _wchar_utf8sntowcs(dst, len, src, NMC, ps, 1))
				!= (size_t) -2) ? r : 0;
	}
#endif
	incr = 1;
	/* NOTE: The following is an AWFUL HACK!  In order to support %s in
	 * wprintf, we need to be able to compute the number of wchars needed
	 * for the mbs conversion, not to exceed the precision specified.
	 * But if dst is NULL, the return value is the length assuming a
	 * sufficiently sized buffer.  So, we allow passing of ((wchar_t *)ps)
	 * as dst in order to flag that we really want the length, subject
	 * to the restricted buffer size and no partial conversions.
	 * See _wchar_utf8sntowcs() as well. */
	if (!dst || (dst == ((wchar_t *)ps))) {
		if (!dst) {
			len = SIZE_MAX;
		}
		dst = wcbuf;
		incr = 0;
	}

	/* Since all the following encodings are single-byte encodings... */
	if (len > NMC) {
		len = NMC;
	}

	count = len;
	s = *src;

#ifdef __CTYPE_HAS_8_BIT_LOCALES
	if (ENCODING == __ctype_encoding_8_bit) {
		wchar_t wc;
		while (count) {
			if ((wc = ((unsigned char)(*s))) >= 0x80) {	/* Non-ASCII... */
				wc -= 0x80;
				wc = __global_locale.tbl8c2wc[
						  (__global_locale.idx8c2wc[wc >> Cc2wc_IDX_SHIFT]
						   << Cc2wc_IDX_SHIFT) + (wc & (Cc2wc_ROW_LEN - 1))];
				if (!wc) {
					goto BAD;
				}
			}
			if (!(*dst = wc)) {
				s = NULL;
				break;
			}
			dst += incr;
			++s;
			--count;
		}
		if (dst != wcbuf) {
			*src = s;
		}
		return len - count;
	}
#endif

#ifdef __UCLIBC_HAS_LOCALE__
	assert(ENCODING == __ctype_encoding_7_bit);
#endif

	while (count) {
		if ((*dst = (unsigned char) *s) == 0) {
			s = NULL;
			break;
		}
		if (*dst >= 0x80) {
#ifdef __CTYPE_HAS_8_BIT_LOCALES
		BAD:
#endif
			__set_errno(EILSEQ);
			return (size_t) -1;
		}
		++s;
		dst += incr;
		--count;
	}
	if (dst != wcbuf) {
		*src = s;
	}
	return len - count;
}

#endif
/**********************************************************************/
#ifdef L___wcsnrtombs

/* WARNING: We treat len as SIZE_MAX when dst is NULL! */

/* Note: We completely ignore ps in all currently supported conversions.
 * TODO: Check for valid state anyway? */

size_t wcsnrtombs(char *__restrict dst, const wchar_t **__restrict src,
				  size_t NWC, size_t len, mbstate_t *__restrict ps)
	 __attribute__ ((__weak__, __alias__("__wcsnrtombs")));

size_t __wcsnrtombs(char *__restrict dst, const wchar_t **__restrict src,
					size_t NWC, size_t len, mbstate_t *__restrict ps)
{
	const __uwchar_t *s;
	size_t count;
	int incr;
	char buf[MB_LEN_MAX];

#ifdef __CTYPE_HAS_UTF_8_LOCALES
	if (ENCODING == __ctype_encoding_utf8) {
		return _wchar_wcsntoutf8s(dst, len, src, NWC);
	}
#endif /* __CTYPE_HAS_UTF_8_LOCALES */

	incr = 1;
	/* NOTE: The following is an AWFUL HACK!  In order to support %ls in
	 * printf, we need to be able to compute the number of bytes needed
	 * for the mbs conversion, not to exceed the precision specified.
	 * But if dst is NULL, the return value is the length assuming a
	 * sufficiently sized buffer.  So, we allow passing of (char *) src
	 * as dst in order to flag that we really want the length, subject
	 * to the restricted buffer size and no partial conversions.
	 * See _wchar_wcsntoutf8s() as well. */
	if (!dst || (dst == ((char *) src))) {
		if (!dst) {
			len = SIZE_MAX;
		}
		dst = buf;
		incr = 0;
	}

	/* Since all the following encodings are single-byte encodings... */
	if (len > NWC) {
		len = NWC;
	}

	count = len;
	s = (const __uwchar_t *) *src;

#ifdef __CTYPE_HAS_8_BIT_LOCALES
	if (ENCODING == __ctype_encoding_8_bit) {
		__uwchar_t wc;
		__uwchar_t u;
		while (count) {
			if ((wc = *s) <= 0x7f) {
				if (!(*dst = (unsigned char) wc)) {
					s = NULL;
					break;
				}
			} else {
				u = 0;
				if (wc <= Cwc2c_DOMAIN_MAX) {
					u = __global_locale.idx8wc2c[wc >> (Cwc2c_TI_SHIFT
														+ Cwc2c_TT_SHIFT)];
					u = __global_locale.tbl8wc2c[(u << Cwc2c_TI_SHIFT)
									+ ((wc >> Cwc2c_TT_SHIFT)
									   & ((1 << Cwc2c_TI_SHIFT)-1))];
					u = __global_locale.tbl8wc2c[Cwc2c_TI_LEN
									+ (u << Cwc2c_TT_SHIFT)
									+ (wc & ((1 << Cwc2c_TT_SHIFT)-1))];
				}

#define __WCHAR_REPLACEMENT_CHAR '?'
#ifdef __WCHAR_REPLACEMENT_CHAR
				*dst = (unsigned char) ( u ? u : __WCHAR_REPLACEMENT_CHAR );
#else  /* __WCHAR_REPLACEMENT_CHAR */
				if (!u) {
					goto BAD;
				}
				*dst = (unsigned char) u;
#endif /* __WCHAR_REPLACEMENT_CHAR */
			}
			++s;
			dst += incr;
			--count;
		}
		if (dst != buf) {
			*src = (const wchar_t *) s;
		}
		return len - count;
	}
#endif /* __CTYPE_HAS_8_BIT_LOCALES */

#ifdef __UCLIBC_HAS_LOCALE__
	assert(ENCODING == __ctype_encoding_7_bit);
#endif

	while (count) {
		if (*s >= 0x80) {
#if defined(__CTYPE_HAS_8_BIT_LOCALES) && !defined(__WCHAR_REPLACEMENT_CHAR)
		BAD:
#endif
			__set_errno(EILSEQ);
			return (size_t) -1;
		}
		if ((*dst = (unsigned char) *s) == 0) {
			s = NULL;
			break;
		}
		++s;
		dst += incr;
		--count;
	}
	if (dst != buf) {
		*src = (const wchar_t *) s;
	}
	return len - count;
}

#endif
/**********************************************************************/
#ifdef L_wcswidth

#ifdef __UCLIBC_MJN3_ONLY__
#warning if we start doing translit, wcwidth and wcswidth will need updating.
#endif

#if defined(__UCLIBC_HAS_LOCALE__) && \
( defined(__CTYPE_HAS_8_BIT_LOCALES) || defined(__CTYPE_HAS_UTF_8_LOCALES) )

static const unsigned char new_idx[] = {
	0,    5,    5,    6,   10,   15,   28,   39, 
	48,   48,   71,   94,  113,  128,  139,  154, 
	175,  186,  188,  188,  188,  188,  188,  188, 
	203,  208,  208,  208,  208,  208,  208,  208, 
	208,  219,  219,  219,  222,  222,  222,  222, 
	222,  222,  222,  222,  222,  222,  222,  224, 
	224,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  231,  231,  231, 
	231,  231,  231,  231,  231,  233,  233,  233, 
	233,  233,  233,  233,  234,  234,  234,  234, 
	234,  234,  234,  234,  234,  234,  234,  234, 
	234,  234,  234,  234,  234,  234,  234,  234, 
	234,  234,  234,  234,  234,  234,  234,  234, 
	234,  234,  234,  234,  234,  234,  234,  234, 
	234,  234,  234,  234,  234,  234,  234,  234, 
	236,  236,  236,  236,  236,  236,  236,  236, 
	236,  236,  236,  236,  236,  236,  236,  236, 
	236,  236,  236,  236,  236,  236,  236,  236, 
	236,  236,  236,  236,  236,  236,  236,  236, 
	236,  237,  237,  238,  241,  241,  242,  249, 
	255, 
};

static const unsigned char new_tbl[] = {
	0x00, 0x01, 0x20, 0x7f, 0xa0, 0x00, 0x00, 0x50, 
	0x60, 0x70, 0x00, 0x83, 0x87, 0x88, 0x8a, 0x00, 
	0x91, 0xa2, 0xa3, 0xba, 0xbb, 0xbe, 0xbf, 0xc0, 
	0xc1, 0xc3, 0xc4, 0xc5, 0x00, 0x4b, 0x56, 0x70, 
	0x71, 0xd6, 0xe5, 0xe7, 0xe9, 0xea, 0xee, 0x00, 
	0x0f, 0x10, 0x11, 0x12, 0x30, 0x4b, 0xa6, 0xb1, 
	0x00, 0x01, 0x03, 0x3c, 0x3d, 0x41, 0x49, 0x4d, 
	0x4e, 0x51, 0x55, 0x62, 0x64, 0x81, 0x82, 0xbc, 
	0xbd, 0xc1, 0xc5, 0xcd, 0xce, 0xe2, 0xe4, 0x00, 
	0x02, 0x03, 0x3c, 0x3d, 0x41, 0x43, 0x47, 0x49, 
	0x4b, 0x4e, 0x70, 0x72, 0x81, 0x83, 0xbc, 0xbd, 
	0xc1, 0xc6, 0xc7, 0xc9, 0xcd, 0xce, 0x00, 0x01, 
	0x02, 0x3c, 0x3d, 0x3f, 0x40, 0x41, 0x44, 0x4d, 
	0x4e, 0x56, 0x57, 0x82, 0x83, 0xc0, 0xc1, 0xcd, 
	0xce, 0x00, 0x3e, 0x41, 0x46, 0x49, 0x4a, 0x4e, 
	0x55, 0x57, 0xbf, 0xc0, 0xc6, 0xc7, 0xcc, 0xce, 
	0x00, 0x41, 0x44, 0x4d, 0x4e, 0xca, 0xcb, 0xd2, 
	0xd5, 0xd6, 0xd7, 0x00, 0x31, 0x32, 0x34, 0x3b, 
	0x47, 0x4f, 0xb1, 0xb2, 0xb4, 0xba, 0xbb, 0xbd, 
	0xc8, 0xce, 0x00, 0x18, 0x1a, 0x35, 0x36, 0x37, 
	0x38, 0x39, 0x3a, 0x71, 0x7f, 0x80, 0x85, 0x86, 
	0x88, 0x90, 0x98, 0x99, 0xbd, 0xc6, 0xc7, 0x00, 
	0x2d, 0x31, 0x32, 0x33, 0x36, 0x38, 0x39, 0x3a, 
	0x58, 0x5a, 0x00, 0x60, 0x00, 0x12, 0x15, 0x32, 
	0x35, 0x52, 0x54, 0x72, 0x74, 0xb7, 0xbe, 0xc6, 
	0xc7, 0xc9, 0xd4, 0x00, 0x0b, 0x0f, 0xa9, 0xaa, 
	0x00, 0x0b, 0x10, 0x2a, 0x2f, 0x60, 0x64, 0x6a, 
	0x70, 0xd0, 0xeb, 0x00, 0x29, 0x2b, 0x00, 0x80, 
	0x00, 0x2a, 0x30, 0x3f, 0x40, 0x99, 0x9b, 0x00, 
	0xd0, 0x00, 0x00, 0xa4, 0x00, 0x00, 0x00, 0x1e, 
	0x1f, 0x00, 0x00, 0x10, 0x20, 0x24, 0x30, 0x70, 
	0xff, 0x00, 0x61, 0xe0, 0xe7, 0xf9, 0xfc, 
};

static const signed char new_wtbl[] = {
	0,   -1,    1,   -1,    1,    1,    0,    1, 
	0,    1,    1,    0,    1,    0,    1,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    0,    1,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    0,    1,    0,    1,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    1,    0,    1,    0,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    1, 
	0,    1,    0,    1,    0,    1,    0,    1, 
	0,    1,    2,    0,    1,    0,    1,    0, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    1,    0,    1,    0,    1, 
	1,    0,    1,    0,    1,    0,    1,    0, 
	1,    0,    1,    1,    2,    1,    1,    2, 
	2,    0,    2,    1,    2,    0,    2,    2, 
	1,    1,    2,    1,    1,    2,    1,    0, 
	1,    1,    0,    1,    0,    1,    2,    1, 
	0,    2,    1,    2,    1,    0,    1, 
};

int wcswidth(const wchar_t *pwcs, size_t n)
{
    int h, l, m, count;
    wchar_t wc;
    unsigned char b;

	if (ENCODING == __ctype_encoding_7_bit) {
		size_t i;
		
		for (i = 0 ; (i < n) && pwcs[i] ; i++) {
			if (pwcs[i] != ((unsigned char)(pwcs[i]))) {
				return -1;
			}
		}
	}
#ifdef __CTYPE_HAS_8_BIT_LOCALES
	else if (ENCODING == __ctype_encoding_8_bit) {
		mbstate_t mbstate;

		mbstate.mask = 0;			/* Initialize the mbstate. */
		if (__wcsnrtombs(NULL, &pwcs, n, SIZE_MAX, &mbstate) == ((size_t) - 1)) {
			return -1;
		}
	}
#endif /* __CTYPE_HAS_8_BIT_LOCALES */
#if defined(__CTYPE_HAS_UTF_8_LOCALES) && defined(KUHN)
	/* For stricter handling of allowed unicode values... see comments above. */
	else if (ENCODING == __ctype_encoding_utf8) {
		size_t i;
		
		for (i = 0 ; (i < n) && pwcs[i] ; i++) {
			if ( (((__uwchar_t)((pwcs[i]) - 0xfffeU)) < 2)
				 || (((__uwchar_t)((pwcs[i]) - 0xd800U)) < (0xe000U - 0xd800U))
				) {
				return -1;
			}
		}
	}
#endif /* __CTYPE_HAS_UTF_8_LOCALES */

    for (count = 0 ; n && (wc = *pwcs++) ; n--) {
		if (wc <= 0xff) {
			/* If we're here, wc != 0. */
			if ((wc < 32) || ((wc >= 0x7f) && (wc < 0xa0))) {
				return -1;
			}
			++count;
			continue;
		}
		if (((unsigned int) wc) <= 0xffff) {
			b = wc & 0xff;
			h = (wc >> 8);
			l = new_idx[h];
			h = new_idx[h+1];
			while ((m = (l+h) >> 1) != l) {
				if (b >= new_tbl[m]) {
					l = m;
				} else {		/* wc < tbl[m] */
					h = m;
				}
			}
			count += new_wtbl[l]; /* none should be -1. */
			continue;
		}

		/* Redo this to minimize average number of compares?*/
		if (wc >= 0x1d167) {
			if (wc <= 0x1d1ad) {
				if ((wc <= 0x1d169
					 || (wc >= 0x1d173
						 && (wc <= 0x1d182
							 || (wc >= 0x1d185
								 && (wc <= 0x1d18b
									 || (wc >= 0x1d1aa))))))
					) {
					continue;
				}
			} else if (((wc >= 0xe0020) && (wc <= 0xe007f)) || (wc == 0xe0001)) {
				continue;
			} else if ((wc >= 0x20000) && (wc <= 0x2ffff)) {
				++count;		/* need 2.. add one here */
			}
#if (WCHAR_MAX > 0x7fffffffL)
			else if (wc > 0x7fffffffL) {
				return -1;
			}
#endif /* (WCHAR_MAX > 0x7fffffffL) */
		}

		++count;
    }

    return count;
}

#else  /*  __UCLIBC_HAS_LOCALE__ */

int wcswidth(const wchar_t *pwcs, size_t n)
{
	int count;
	wchar_t wc;

    for (count = 0 ; n && (wc = *pwcs++) ; n--) {
		if (wc <= 0xff) {
			/* If we're here, wc != 0. */
			if ((wc < 32) || ((wc >= 0x7f) && (wc < 0xa0))) {
				return -1;
			}
			++count;
			continue;
		} else {
			return -1;
		}
	}

	return count;
}

#endif /*  __UCLIBC_HAS_LOCALE__ */

#endif
/**********************************************************************/
#ifdef L_wcwidth

int wcwidth(wchar_t wc)
{
    return wcswidth(&wc, 1);
}

#endif
/**********************************************************************/