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

typedef struct {
	mbstate_t tostate;
	mbstate_t fromstate;
	int tocodeset;
	int fromcodeset;
	int frombom;
	int tobom;
	int fromcodeset0;
	int frombom0;
	int tobom0;
	int skip_invalid_input;		/* To support iconv -c option. */
} _UC_iconv_t;



#ifdef L_iconv

#include <iconv.h>
#include <string.h>
#include <endian.h>
#include <byteswap.h>

#if (__BYTE_ORDER != __BIG_ENDIAN) && (__BYTE_ORDER != __LITTLE_ENDIAN)
#error unsupported endianness for iconv
#endif

#ifndef __CTYPE_HAS_8_BIT_LOCALES
#error currently iconv requires 8 bit locales
#endif
#ifndef __CTYPE_HAS_UTF_8_LOCALES
#error currently iconv requires UTF-8 locales
#endif


enum {
	IC_WCHAR_T = 0xe0,
	IC_MULTIBYTE = 0xe0,
#if __BYTE_ORDER == __BIG_ENDIAN
	IC_UCS_4 =	0xec,
	IC_UTF_32 = 0xe4,
	IC_UCS_2 =	0xe2,
	IC_UTF_16 = 0xea,
#else
	IC_UCS_4 =	0xed,
	IC_UTF_32 = 0xe5,
	IC_UCS_2 =	0xe3,
	IC_UTF_16 = 0xeb,
#endif
	IC_UTF_8 = 2,
	IC_ASCII = 1
};

/* For the multibyte
 * bit 0 means swap endian
 * bit 1 means 2 byte
 * bit 2 means 4 byte
 *
 */

const unsigned char codesets[] =
	"\x0a\xe0""WCHAR_T\x00"		/* superset of UCS-4 but platform-endian */
#if __BYTE_ORDER == __BIG_ENDIAN
	"\x08\xec""UCS-4\x00"		/* always BE */
	"\x0a\xec""UCS-4BE\x00"
	"\x0a\xed""UCS-4LE\x00"
	"\x09\fe4""UTF-32\x00"		/* platform endian with BOM */
	"\x0b\xe4""UTF-32BE\x00"
	"\x0b\xe5""UTF-32LE\x00"
	"\x08\xe2""UCS-2\x00"		/* always BE */
	"\x0a\xe2""UCS-2BE\x00"
	"\x0a\xe3""UCS-2LE\x00"
	"\x09\xea""UTF-16\x00"		/* platform endian with BOM */
	"\x0b\xea""UTF-16BE\x00"
	"\x0b\xeb""UTF-16LE\x00"
#elif __BYTE_ORDER == __LITTLE_ENDIAN
	"\x08\xed""UCS-4\x00"		/* always BE */
	"\x0a\xed""UCS-4BE\x00"
	"\x0a\xec""UCS-4LE\x00"
	"\x09\xf4""UTF-32\x00"		/* platform endian with BOM */
	"\x0b\xe5""UTF-32BE\x00"
	"\x0b\xe4""UTF-32LE\x00"
	"\x08\xe3""UCS-2\x00"		/* always BE */
	"\x0a\xe3""UCS-2BE\x00"
	"\x0a\xe2""UCS-2LE\x00"
	"\x09\xfa""UTF-16\x00"		/* platform endian with BOM */
	"\x0b\xeb""UTF-16BE\x00"
	"\x0b\xea""UTF-16LE\x00"
#endif
	"\x08\x02""UTF-8\x00"
	"\x0b\x01""US-ASCII\x00"
	"\x07\x01""ASCII";			/* Must be last! (special case to save a nul) */

static int find_codeset(const char *name)
{
	const unsigned char *s;
	int codeset;

	for (s = codesets ; *s ; s += *s) {
		if (!strcasecmp(s+2, name)) {
			return s[1];
		}
	}

	/* The following is ripped from find_locale in locale.c. */

	/* TODO: maybe CODESET_LIST + *s ??? */
	/* 7bit is 1, UTF-8 is 2, 8-bit is >= 3 */
	codeset = 2;
	s = CODESET_LIST;
	do {
		++codeset;		/* Increment codeset first. */
		if (!strcasecmp(CODESET_LIST+*s, name)) {
			return codeset;
		}
	} while (*++s);

	return 0;			/* No matching codeset! */
}

iconv_t iconv_open(const char *tocode, const char *fromcode)
{
	register _UC_iconv_t *px;
	int tocodeset, fromcodeset;

	if (((tocodeset = find_codeset(tocode)) != 0)
		&& ((fromcodeset = find_codeset(fromcode)) != 0)) {
		if ((px = malloc(sizeof(_UC_iconv_t))) != NULL) {
			px->tocodeset = tocodeset;
			px->tobom0 = px->tobom = (tocodeset & 0x10) >> 4;
			px->fromcodeset0 = px->fromcodeset = fromcodeset;
			px->frombom0 = px->frombom = (fromcodeset & 0x10) >> 4;
			px->skip_invalid_input = px->tostate.mask = px->fromstate.mask = 0;
			return (iconv_t) px;
		}
	} else {
		__set_errno(EINVAL);
	}
	return (iconv_t)(-1);
}

int iconv_close(iconv_t cd)
{
	free(cd);

	return 0;
}

size_t iconv(iconv_t cd, char **__restrict inbuf,
			 size_t *__restrict inbytesleft,
		     char **__restrict outbuf, size_t *__restrict outbytesleft)
{
	_UC_iconv_t *px = (_UC_iconv_t *) cd;
	size_t nrcount, r;
	wchar_t wc, wc2;
	int inci, inco;

	assert(px != (_UC_iconv_t *)(-1));
	assert(sizeof(wchar_t) == 4);

	if (!inbuf || !*inbuf) {	/* Need to reinitialze conversion state. */
		/* Note: For shift-state encodings we possibly need to output the
		 * shift sequence to return to initial state! */
		if ((px->fromcodeset & 0xf0) == 0xe0) {
		}
		px->tostate.mask = px->fromstate.mask = 0;
		px->fromcodeset = px->fromcodeset0;
		px->tobom = px->tobom0;
		px->frombom = px->frombom0;
		return 0;
	}

	nrcount = 0;
	while (*inbytesleft) {
		if (!*outbytesleft) {
		TOO_BIG:
			__set_errno(E2BIG);
			return (size_t) -1;
		}

		inci = inco = 1;
		if (px->fromcodeset >= IC_MULTIBYTE) {
			inci = (px->fromcodeset == IC_WCHAR_T) ? 4: (px->fromcodeset & 6);
			if (*inbytesleft < inci) goto INVALID;
			wc = (((unsigned int)((unsigned char)((*inbuf)[0]))) << 8)
				+ ((unsigned char)((*inbuf)[1]));
			if (inci == 4) {
				wc = (((unsigned int)((unsigned char)((*inbuf)[2]))) << 8)
					+ ((unsigned char)((*inbuf)[3])) + (wc << 16);
				if (!(px->fromcodeset & 1)) wc = bswap_32(wc);
			} else {
				if (!(px->fromcodeset & 1)) wc = bswap_16(wc);
				if (((px->fromcodeset & IC_UTF_16) == IC_UTF_16)
					 && (((__uwchar_t)(wc - 0xd800U)) < (0xdc00U - 0xd800U))
					) {			/* surrogate */
					wc =- 0xd800U;
					if (*inbytesleft < 4) goto INVALID;
					wc2 = (((unsigned int)((unsigned char)((*inbuf)[2]))) << 8)
						+ ((unsigned char)((*inbuf)[3]));
					if (!(px->fromcodeset & 1)) wc = bswap_16(wc2);
					if (((__uwchar_t)(wc2 -= 0xdc00U)) < (0xe0000U - 0xdc00U)) {
						goto ILLEGAL;
					}
					inci = 4;	/* Change inci here in case skipping illegals. */
					wc = 0x10000UL + (wc << 10) + wc2;
				}
			}

			if (px->frombom) {
				px->frombom = 0;
				if ((wc == 0xfeffU)
					|| (wc == ((inci == 4)
							   ? (((wchar_t) 0xfffe0000UL))
							   : ((wchar_t)(0xfffeUL))))
					) {
					if (wc != 0xfeffU) {
						px->fromcodeset ^= 1; /* toggle endianness */
						wc = 0xfeffU;
					}
					if (!px->frombom) {
						goto BOM_SKIP_OUTPUT;
					}
					goto GOT_BOM;
				}
			}

			if (px->fromcodeset != IC_WCHAR_T) {
				if (((__uwchar_t) wc) > (((px->fromcodeset & IC_UCS_4) == IC_UCS_4)
										 ? 0x7fffffffUL : 0x10ffffUL)
#ifdef KUHN
					|| (((__uwchar_t)(wc - 0xfffeU)) < 2)
					|| (((__uwchar_t)(wc - 0xd800U)) < (0xe000U - 0xd800U))
#endif
					) {
					goto ILLEGAL;
				}
			}
		} else if (px->fromcodeset == IC_UTF_8) {
			const char *p = *inbuf;
			r = _wchar_utf8sntowcs(&wc, 1, &p, *inbytesleft, &px->fromstate, 0);
			if (((ssize_t) r) <= 0) { /* either EILSEQ or incomplete or nul */
				if (((ssize_t) r) < 0) { /* either EILSEQ or incomplete or nul */
					assert((r == (size_t)(-1)) || (r == (size_t)(-2)));
					if (r == (size_t)(-2)) {
					INVALID:
						__set_errno(EINVAL);
					} else {
						px->fromstate.mask = 0;
						inci = 1;
					ILLEGAL:
						if (px->skip_invalid_input) {
							px->skip_invalid_input = 2;	/* flag for iconv utility */
							goto BOM_SKIP_OUTPUT;
						}
						__set_errno(EILSEQ);
					}
					return (size_t)(-1);
				}
#ifdef __UCLIBC_MJN3_ONLY__
#warning optimize this
#endif
				if (p != NULL) { /* incomplet char case */
					goto INVALID;
				}
				p = *inbuf + 1;	/* nul */
			}
			inci = p - *inbuf;
		} else if ((wc = ((unsigned char)(**inbuf))) >= 0x80) {	/* Non-ASCII... */
			if (px->fromcodeset == IC_ASCII) { /* US-ASCII codeset */
				goto ILLEGAL;
			} else {			/* some other 8-bit ascii-extension codeset */
				const codeset_8_bit_t *c8b
					= __locale_mmap->codeset_8_bit + px->fromcodeset - 3;
				wc -= 0x80;
				wc = __global_locale.tbl8c2wc[
							 (c8b->idx8c2wc[wc >> Cc2wc_IDX_SHIFT]
							  << Cc2wc_IDX_SHIFT) + (wc & (Cc2wc_ROW_LEN - 1))];
				if (!wc) {
					goto ILLEGAL;
				}
			}
		}


		if (px->tobom) {
			inci = 0;
			wc = 0xfeffU;
	GOT_BOM:
			px->tobom = 0;
		}

		if (px->tocodeset >= IC_MULTIBYTE) {
			inco = (px->tocodeset == IC_WCHAR_T) ? 4: (px->tocodeset & 6);
			if (*outbytesleft < inci) goto TOO_BIG;
			if (px->tocodeset != IC_WCHAR_T) {
				if (((__uwchar_t) wc) > (((px->tocodeset & IC_UCS_4) == IC_UCS_4)
										 ? 0x7fffffffUL : 0x10ffffUL)
#ifdef KUHN
					|| (((__uwchar_t)(wc - 0xfffeU)) < 2)
					|| (((__uwchar_t)(wc - 0xd800U)) < (0xe000U - 0xd800U))
#endif
					) {
				REPLACE_32:
					wc = 0xfffd;
					++nrcount;
				}
			}
			if (inco == 4) {
				if (px->tocodeset & 1) wc = bswap_32(wc);
			} else {
				if (((__uwchar_t)wc ) > 0xffffU) {
					if ((px->tocodeset & IC_UTF_16) != IC_UTF_16) {
						goto REPLACE_32;
					}
					if (*outbytesleft < (inco = 4)) goto TOO_BIG;
					wc2 = 0xdc00U + (wc & 0x3ff);
					wc = 0xd800U + ((wc >> 10) & 0x3ff);
					if (px->tocodeset & 1) {
						wc = bswap_16(wc);
						wc2 = bswap_16(wc2);
					}
					wc += (wc2 << 16);
				} else if (px->tocodeset & 1) wc = bswap_16(wc);
			}				
			(*outbuf)[0] = (char)((unsigned char)(wc));
			(*outbuf)[1] = (char)((unsigned char)(wc >> 8));
			if (inco == 4) {
				(*outbuf)[2] = (char)((unsigned char)(wc >> 16));
				(*outbuf)[3] = (char)((unsigned char)(wc >> 24));
			}
		} else if (px->tocodeset == IC_UTF_8) {
			const wchar_t *pw = &wc;
			do {
				r = _wchar_wcsntoutf8s(*outbuf, *outbytesleft, &pw, 1);
				if (r != (size_t)(-1)) {
#ifdef __UCLIBC_MJN3_ONLY__
#warning what happens for a nul?
#endif
					if (r == 0) {
						if (wc != 0) {
							goto TOO_BIG;
						}
						++r;
					}
					break;
				}
				wc = 0xfffdU;
				++nrcount;
			} while (1);
			inco = r;
		} else if (((__uwchar_t)(wc)) < 0x80) {
		CHAR_GOOD:
				**outbuf = wc;
		} else {
			if ((px->tocodeset != 0x01) && (wc <= Cwc2c_DOMAIN_MAX)) {
				const codeset_8_bit_t *c8b
					= __locale_mmap->codeset_8_bit + px->tocodeset - 3;
				__uwchar_t u;
				u = c8b->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))];
				wc = __global_locale.tbl8wc2c[Cwc2c_TI_LEN
						 + (u << Cwc2c_TT_SHIFT)
						 + (wc & ((1 << Cwc2c_TT_SHIFT)-1))];
				if (wc) {
					goto CHAR_GOOD;
				}
			}
			**outbuf = '?';
			++nrcount;
		}

		*outbuf += inco;
		*outbytesleft -= inco;
	BOM_SKIP_OUTPUT:
		*inbuf += inci;
		*inbytesleft -= inci;
	}
	return nrcount;
}

#endif
/**********************************************************************/
#ifdef L_iconv_main

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <iconv.h>
#include <stdarg.h>
#include <libgen.h>

extern const unsigned char codesets[];

#define IBUF BUFSIZ
#define OBUF BUFSIZ

char *progname;
int hide_errors;

static void error_msg(const char *fmt, ...) 
	 __attribute__ ((noreturn, format (printf, 1, 2)));

static void error_msg(const char *fmt, ...) 
{
	va_list arg;

	if (!hide_errors) {
		fprintf(stderr, "%s: ", progname);
		va_start(arg, fmt);
		vfprintf(stderr, fmt, arg);
		va_end(arg);
	}

	exit(EXIT_FAILURE);
}

int main(int argc, char **argv)
{
	FILE *ifile;
	FILE *ofile = stdout;
	const char *p;
	const char *s;
	static const char opt_chars[] = "tfocsl";
	                              /* 012345 */
	const char *opts[sizeof(opt_chars)]; /* last is infile name */
	iconv_t ic;
	char ibuf[IBUF];
	char obuf[OBUF];
	char *pi;
	char *po;
	size_t ni, no, r, pos;

	hide_errors = 0;

	for (s = opt_chars ; *s ; s++) {
		opts[ s - opt_chars ] = NULL;
	}

	progname = *argv;
	while (--argc) {
		p = *++argv;
		if ((*p != '-') || (*++p == 0)) {
			break;
		}
		do {
			if ((s = strchr(opt_chars,*p)) == NULL) {
			USAGE:
				s = basename(progname);
				fprintf(stderr,
						"%s [-cs] -f fromcode -t tocode [-o outputfile] [inputfile ...]\n"
						"  or\n%s -l\n", s, s);
				return EXIT_FAILURE;
			}
			if ((s - opt_chars) < 3) {
				if ((--argc == 0) || opts[s - opt_chars]) {
					goto USAGE;
				}
				opts[s - opt_chars] = *++argv;
			} else {
				opts[s - opt_chars] = p;
			}
		} while (*++p);
	}

	if (opts[5]) {				/* -l */
		fprintf(stderr, "Recognized codesets:\n");
		for (s = codesets ; *s ; s += *s) {
			fprintf(stderr,"  %s\n", s+2);
		}
		s = CODESET_LIST;
		do {
			fprintf(stderr,"  %s\n", CODESET_LIST+ (unsigned char)(*s));
		} while (*++s);

		return EXIT_SUCCESS;
	}

	if (opts[4]) {
		hide_errors = 1;
	}

	if (!opts[0] || !opts[1]) {
		goto USAGE;
	}
	if ((ic = iconv_open(opts[0],opts[1])) == ((iconv_t)(-1))) {
		error_msg( "unsupported codeset in %s -> %s conversion\n", opts[0], opts[1]);
	}
	if (opts[3]) {				/* -c */
		((_UC_iconv_t *) ic)->skip_invalid_input = 1;
	}

	if ((s = opts[2]) != NULL) {
		if (!(ofile = fopen(s, "w"))) {
			error_msg( "couldn't open %s for writing\n", s);
		}
	}

	pos = ni = 0;
	do {
		if (!argc || ((**argv == '-') && !((*argv)[1]))) {
			ifile = stdin;		/* we don't check for duplicates */
		} else if (!(ifile = fopen(*argv, "r"))) {
			error_msg( "couldn't open %s for reading\n", *argv);
		}

		while ((r = fread(ibuf + ni, 1, IBUF - ni, ifile)) > 0) {
			pos += r;
			ni += r;
			no = OBUF;
			pi = ibuf;
			po = obuf;
			if ((r = iconv(ic, &pi, &ni, &po, &no)) == ((size_t)(-1))) {
				if ((errno != EINVAL) && (errno != E2BIG)) {
					error_msg( "iconv failed at pos %lu : %m\n", (unsigned long) (pos - ni));
				}
			}
			if ((r = OBUF - no) > 0) {
				if (fwrite(obuf, 1, OBUF - no, ofile) < r) {
					error_msg( "write error\n");
				}
			}
			if (ni) {			/* still bytes in buffer! */
				memmove(ibuf, pi, ni);
			}
		}

		if (ferror(ifile)) {
			error_msg( "read error\n");
		}

		++argv;

		if (ifile != stdin) {
			fclose(ifile);
		}

	} while (--argc > 0);

	iconv_close(ic);

	if (ni) {
		error_msg( "incomplete sequence\n");
	}

	return (((_UC_iconv_t *) ic)->skip_invalid_input < 2)
		? EXIT_SUCCESS : EXIT_FAILURE;
}

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