add libiconv-tiny implementation

To use it enable UCLIBC_HAS_LIBICONV, then iconv_open/iconv_close
should be available.

1 files changed, 440 insertions, 0 deletions

diff --git a/libiconv/iconv.c b/libiconv/iconv.c
new file mode 100644
index 000000000..cb4e94775
--- /dev/null
+++ b/libiconv/iconv.c
@@ -0,0 +1,440 @@
+#include <iconv.h>
+#include <errno.h>
+#include <wchar.h>
+#include <string.h>
+#include <strings.h>
+#include <stdlib.h>
+#include <limits.h>
+
+#include <dirent.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdint.h>
+
+/* builtin charmaps */
+#include "charmaps.h"
+
+/* only 0-7 are valid as dest charset */
+#define UTF_16BE    000
+#define UTF_16LE    001
+#define UTF_32BE    002
+#define UTF_32LE    003
+#define WCHAR_T     004
+#define UTF_8       005
+#define US_ASCII    006
+#define LATIN_1     007
+
+/* additional charsets with algorithmic conversion */
+#define LATIN_9     010
+#define TIS_620     011
+#define JIS_0201    012
+
+/* some programs like php need this */
+int _libiconv_version = _LIBICONV_VERSION;
+
+/* these must match the constants above */
+static const unsigned char charsets[] =
+	"\005" "UTF-8"      "\0"
+	"\004" "WCHAR_T"    "\0"
+	"\000" "UTF-16BE"   "\0"
+	"\001" "UTF-16LE"   "\0"
+	"\002" "UTF-32BE"   "\0"
+	"\003" "UTF-32LE"   "\0"
+	"\006" "ASCII"      "\0"
+	"\006" "US-ASCII"   "\0"
+	"\007" "ISO-8859-1" "\0"
+	"\007" "LATIN1"     "\0"
+	"\010" "ISO-8859-15""\0"
+	"\010" "LATIN9"     "\0"
+	"\011" "ISO-8859-11""\0"
+	"\011" "TIS-620"    "\0"
+	"\012" "JIS-0201"   "\0"
+	"\377";
+
+/* separate identifiers for sbcs/dbcs/etc map type */
+#define UCS2_8BIT   000
+#define UCS3_8BIT   001
+#define EUC         002
+#define EUC_TW      003
+#define SHIFT_JIS   004
+#define BIG5        005
+#define GBK         006
+
+/* FIXME: these are not implemented yet
+// EUC:   A1-FE A1-FE
+// GBK:   81-FE 40-7E,80-FE
+// Big5:  A1-FE 40-7E,A1-FE
+*/
+
+static const unsigned short maplen[] = {
+	[UCS2_8BIT] = 4+ 2* 128,
+	[UCS3_8BIT] = 4+ 3* 128,
+	[EUC]       = 4+ 2* 94*94,
+	[SHIFT_JIS] = 4+ 2* 94*94,
+	[BIG5]      = 4+ 2* 94*157,
+	[GBK]       = 4+ 2* 126*190,
+	[EUC_TW]    = 4+ 2* 2*94*94,
+};
+
+static int find_charmap(const char *name)
+{
+	int i;
+	for (i = 0; i < (sizeof(charmaps) / sizeof(charmaps[0])); i++)
+		if (!strcasecmp(charmaps[i].name, name))
+			return i;
+	return -1;
+}
+
+static int find_charset(const char *name)
+{
+	const unsigned char *s;
+	for (s=charsets; *s<0xff && strcasecmp(s+1, name); s+=strlen(s)+1);
+	return *s;
+}
+
+iconv_t iconv_open(const char *to, const char *from)
+{
+	unsigned f, t;
+	int m;
+
+	if ((t = find_charset(to)) > 8)
+		return -1;
+
+	if ((f = find_charset(from)) < 255)
+		return 0 | (t<<1) | (f<<8);
+
+	if ((m = find_charmap(from)) > -1)
+		return 1 | (t<<1) | (m<<8);
+
+	return -1;
+}
+
+int iconv_close(iconv_t cd)
+{
+	return 0;
+}
+
+static inline wchar_t get_16(const unsigned char *s, int endian)
+{
+	endian &= 1;
+	return s[endian]<<8 | s[endian^1];
+}
+
+static inline void put_16(unsigned char *s, wchar_t c, int endian)
+{
+	endian &= 1;
+	s[endian] = c>>8;
+	s[endian^1] = c;
+}
+
+static inline int utf8enc_wchar(char *outb, wchar_t c)
+{
+	if (c <= 0x7F) {
+		*outb = c;
+		return 1;
+	}
+	else if (c <= 0x7FF) {
+		*outb++ = ((c >>  6) & 0x1F) | 0xC0;
+		*outb++ = ( c        & 0x3F) | 0x80;
+		return 2;
+	}
+	else if (c <= 0xFFFF) {
+		*outb++ = ((c >> 12) & 0x0F) | 0xE0;
+		*outb++ = ((c >>  6) & 0x3F) | 0x80;
+		*outb++ = ( c        & 0x3F) | 0x80;
+		return 3;
+	}
+	else if (c <= 0x10FFFF) {
+		*outb++ = ((c >> 18) & 0x07) | 0xF0;
+		*outb++ = ((c >> 12) & 0x3F) | 0x80;
+		*outb++ = ((c >>  6) & 0x3F) | 0x80;
+		*outb++ = ( c        & 0x3F) | 0x80;
+		return 4;
+	}
+	else {
+		*outb++ = '?';
+		return 1;
+	}
+}
+
+static inline int utf8seq_is_overlong(char *s, int n)
+{
+	switch (n)
+	{
+	case 2:
+		/* 1100000x (10xxxxxx) */
+		return (((*s >> 1) == 0x60) &&
+				((*(s+1) >> 6) == 0x02));
+
+	case 3:
+		/* 11100000 100xxxxx (10xxxxxx) */
+		return ((*s == 0xE0) &&
+				((*(s+1) >> 5) == 0x04) &&
+				((*(s+2) >> 6) == 0x02));
+
+	case 4:
+		/* 11110000 1000xxxx (10xxxxxx 10xxxxxx) */
+		return ((*s == 0xF0) &&
+				((*(s+1) >> 4) == 0x08) &&
+				((*(s+2) >> 6) == 0x02) &&
+				((*(s+3) >> 6) == 0x02));
+	}
+
+	return 0;
+}
+
+static inline int utf8seq_is_surrogate(char *s, int n)
+{
+	return ((n == 3) && (*s == 0xED) && (*(s+1) >= 0xA0) && (*(s+1) <= 0xBF));
+}
+
+static inline int utf8seq_is_illegal(char *s, int n)
+{
+	return ((n == 3) && (*s == 0xEF) && (*(s+1) == 0xBF) &&
+	        (*(s+2) >= 0xBE) && (*(s+2) <= 0xBF));
+}
+
+static inline int utf8dec_wchar(wchar_t *c, unsigned char *in, size_t inb)
+{
+	int i;
+	int n = -1;
+
+	/* trivial char */
+	if (*in <= 0x7F) {
+		*c = *in;
+		return 1;
+	}
+
+	/* find utf8 sequence length */
+	if      ((*in & 0xE0) == 0xC0) n = 2;
+	else if ((*in & 0xF0) == 0xE0) n = 3;
+	else if ((*in & 0xF8) == 0xF0) n = 4;
+	else if ((*in & 0xFC) == 0xF8) n = 5;
+	else if ((*in & 0xFE) == 0xFC) n = 6;
+
+	/* starved? */
+	if (n > inb)
+		return -2;
+
+	/* decode ... */
+	if (n > 1 && n < 5) {
+		/* reject invalid sequences */
+		if (utf8seq_is_overlong(in, n) ||
+			utf8seq_is_surrogate(in, n) ||
+			utf8seq_is_illegal(in, n))
+			return -1;
+
+		/* decode ... */
+		*c = (char)(*in++ & (0x7F >> n));
+
+		for (i = 1; i < n; i++) {
+			/* illegal continuation byte */
+			if (*in < 0x80 || *in > 0xBF)
+				return -1;
+
+			*c = (*c << 6) | (*in++ & 0x3F);
+		}
+
+		return n;
+	}
+
+	/* unmapped sequence (> 4) */
+	return -1;
+}
+
+static inline char latin9_translit(wchar_t c)
+{
+	/* a number of trivial iso-8859-15 <> utf-8 transliterations */
+	switch (c) {
+	case 0x20AC: return 0xA4; /* Euro */
+	case 0x0160: return 0xA6; /* S caron */
+	case 0x0161: return 0xA8; /* s caron */
+	case 0x017D: return 0xB4; /* Z caron */
+	case 0x017E: return 0xB8; /* z caron */
+	case 0x0152: return 0xBC; /* OE */
+	case 0x0153: return 0xBD; /* oe */
+	case 0x0178: return 0xBE; /* Y diaeresis */
+	default:     return '?';
+	}
+}
+
+size_t iconv(iconv_t cd, char **in, size_t *inb, char **out, size_t *outb)
+{
+	size_t x=0;
+	unsigned char to = (cd>>1)&127;
+	unsigned char from = 255;
+	const unsigned char *map = 0;
+	char tmp[MB_LEN_MAX];
+	wchar_t c, d;
+	size_t k, l;
+	int err;
+
+	if (!in || !*in || !*inb) return 0;
+
+	if (cd & 1)
+		map = charmaps[cd>>8].map;
+	else
+		from = cd>>8;
+
+	for (; *inb; *in+=l, *inb-=l) {
+		c = *(unsigned char *)*in;
+		l = 1;
+		if (from >= UTF_8 && c < 0x80) goto charok;
+		switch (from) {
+		case WCHAR_T:
+			l = sizeof(wchar_t);
+			if (*inb < l) goto starved;
+			c = *(wchar_t *)*in;
+			break;
+		case UTF_8:
+			l = utf8dec_wchar(&c, *in, *inb);
+			if (!l) l++;
+			else if (l == (size_t)-1) goto ilseq;
+			else if (l == (size_t)-2) goto starved;
+			break;
+		case US_ASCII:
+			goto ilseq;
+		case LATIN_9:
+			if ((unsigned)c - 0xa4 <= 0xbe - 0xa4) {
+				static const unsigned char map[] = {
+					0, 0x60, 0, 0x61, 0, 0, 0, 0, 0, 0, 0,
+					0, 0, 0, 0, 0x7d, 0, 0, 0, 0x7e, 0, 0, 0,
+					0x52, 0x53, 0x78
+				};
+				if (c == 0xa4) c = 0x20ac;
+				else if (map[c-0xa5]) c = 0x100 | map[c-0xa5];
+			}
+		case LATIN_1:
+			goto charok;
+		case TIS_620:
+			if (c >= 0xa1) c += 0x0e01-0xa1;
+			goto charok;
+		case JIS_0201:
+			if (c >= 0xa1) {
+				if (c <= 0xdf) c += 0xff61-0xa1;
+				else goto ilseq;
+			}
+			goto charok;
+		case UTF_16BE:
+		case UTF_16LE:
+			l = 2;
+			if (*inb < 2) goto starved;
+			c = get_16(*in, from);
+			if ((unsigned)(c-0xdc00) < 0x400) goto ilseq;
+			if ((unsigned)(c-0xd800) < 0x400) {
+				l = 4;
+				if (*inb < 4) goto starved;
+				d = get_16(*in + 2, from);
+				if ((unsigned)(c-0xdc00) >= 0x400) goto ilseq;
+				c = ((c-0xd800)<<10) | (d-0xdc00);
+			}
+			break;
+		case UTF_32BE:
+		case UTF_32LE:
+			l = 4;
+			if (*inb < 4) goto starved;
+			// FIXME
+			// c = get_32(*in, from);
+			break;
+		default:
+			/* only support ascii supersets */
+			if (c < 0x80) break;
+			switch (map[0]) {
+			case UCS2_8BIT:
+				c -= 0x80;
+				break;
+			case EUC:
+				if ((unsigned)c - 0xa1 >= 94) goto ilseq;
+				if ((unsigned)in[0][1] - 0xa1 >= 94) goto ilseq;
+				c = (c-0xa1)*94 + (in[0][1]-0xa1);
+				l = 2;
+				break;
+			case SHIFT_JIS:
+				if ((unsigned)c - 0xa1 <= 0xdf-0xa1) {
+					c += 0xff61-0xa1;
+					goto charok;
+				}
+				// FIXME...
+				l = 2;
+				break;
+			default:
+				goto badf;
+			}
+			c = get_16(map + 4 + 2*c, 0);
+			if (c == 0xffff) goto ilseq;
+			goto charok;
+		}
+
+		if ((unsigned)c - 0xd800 < 0x800 || (unsigned)c >= 0x110000)
+			goto ilseq;
+charok:
+		switch (to) {
+		case WCHAR_T:
+			if (*outb < sizeof(wchar_t)) goto toobig;
+			*(wchar_t *)*out = c;
+			*out += sizeof(wchar_t);
+			*outb -= sizeof(wchar_t);
+			break;
+		case UTF_8:
+			if (*outb < 4) {
+				k = utf8enc_wchar(tmp, c);
+				if (*outb < k) goto toobig;
+				memcpy(*out, tmp, k);
+			} else k = utf8enc_wchar(*out, c);
+			*out += k;
+			*outb -= k;
+			break;
+		case US_ASCII:
+			if (c > 0x7f) c = 0xfffd;
+			/* fall thru and count replacement in latin1 case */
+		case LATIN_9:
+			if (c >= 0x100 && c != 0xfffd)
+				c = latin9_translit(c);
+			/* fall through */
+		case LATIN_1:
+			if (!*outb) goto toobig;
+			if (c < 0x100) **out = c;
+			else x++, **out = '*'; //FIXME: translit?
+			++*out;
+			--*outb;
+			break;
+		case UTF_16BE:
+		case UTF_16LE:
+			if (c < 0x10000) {
+				if (*outb < 2) goto toobig;
+				put_16(*out, c, to);
+				*out += 2;
+				*outb -= 2;
+				break;
+			}
+			if (*outb < 4) goto toobig;
+			put_16(*out, (c>>10)|0xd800, to);
+			put_16(*out + 2, (c&0x3ff)|0xdc00, to);
+			*out += 4;
+			*outb -= 4;
+			break;
+		default:
+			goto badf;
+		}
+	}
+	return x;
+ilseq:
+	err = EILSEQ;
+	x = -1;
+	goto end;
+badf:
+	err = EBADF;
+	x = -1;
+	goto end;
+toobig:
+	err = E2BIG;
+	x = -1;
+	goto end;
+starved:
+	err = EINVAL;
+end:
+	errno = err;
+	return x;
+}