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Diffstat (limited to 'lib/util/charset/iconv.c')
| -rw-r--r-- | lib/util/charset/iconv.c | 1196 |
1 files changed, 1196 insertions, 0 deletions
diff --git a/lib/util/charset/iconv.c b/lib/util/charset/iconv.c new file mode 100644 index 0000000..131df64 --- /dev/null +++ b/lib/util/charset/iconv.c @@ -0,0 +1,1196 @@ +/* + Unix SMB/CIFS implementation. + minimal iconv implementation + Copyright (C) Andrew Tridgell 2001 + Copyright (C) Jelmer Vernooij 2002 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "replace.h" +#include "system/iconv.h" +#include "system/filesys.h" +#include "lib/util/byteorder.h" +#include "lib/util/dlinklist.h" +#include "lib/util/charset/charset.h" +#include "lib/util/charset/charset_proto.h" + +#ifdef HAVE_ICU_I18N +#include <unicode/ustring.h> +#include <unicode/utrans.h> +#endif + +#ifdef strcasecmp +#undef strcasecmp +#endif + +/** + * @file + * + * @brief Samba wrapper/stub for iconv character set conversion. + * + * iconv is the XPG2 interface for converting between character + * encodings. This file provides a Samba wrapper around it, and also + * a simple reimplementation that is used if the system does not + * implement iconv. + * + * Samba only works with encodings that are supersets of ASCII: ascii + * characters like whitespace can be tested for directly, multibyte + * sequences start with a byte with the high bit set, and strings are + * terminated by a nul byte. + * + * Note that the only function provided by iconv is conversion between + * characters. It doesn't directly support operations like + * uppercasing or comparison. We have to convert to UTF-16LE and + * compare there. + * + * @sa Samba Developers Guide + **/ + +static size_t ascii_pull (void *,const char **, size_t *, char **, size_t *); +static size_t ascii_push (void *,const char **, size_t *, char **, size_t *); +static size_t latin1_pull(void *,const char **, size_t *, char **, size_t *); +static size_t latin1_push(void *,const char **, size_t *, char **, size_t *); +static size_t utf8_pull (void *,const char **, size_t *, char **, size_t *); +static size_t utf8_push (void *,const char **, size_t *, char **, size_t *); +static size_t utf16_munged_pull(void *,const char **, size_t *, char **, size_t *); +static size_t ucs2hex_pull(void *,const char **, size_t *, char **, size_t *); +static size_t ucs2hex_push(void *,const char **, size_t *, char **, size_t *); +static size_t iconv_copy (void *,const char **, size_t *, char **, size_t *); +static size_t iconv_swab (void *,const char **, size_t *, char **, size_t *); + +static const struct charset_functions builtin_functions[] = { + /* windows is closest to UTF-16 */ + { + .name = "UCS-2LE", + .pull = iconv_copy, + .push = iconv_copy + }, + { + .name = "UTF-16LE", + .pull = iconv_copy, + .push = iconv_copy + }, + { + .name = "UCS-2BE", + .pull = iconv_swab, + .push = iconv_swab + }, + { + .name = "UTF-16BE", + .pull = iconv_swab, + .push = iconv_swab + }, + + /* we include the UTF-8 alias to cope with differing locale settings */ + { + .name = "UTF8", + .pull = utf8_pull, + .push = utf8_push + }, + { + .name = "UTF-8", + .pull = utf8_pull, + .push = utf8_push + }, + + /* this handles the munging needed for String2Key */ + { + .name = "UTF16_MUNGED", + .pull = utf16_munged_pull, + .push = iconv_copy, + .samba_internal_charset = true + }, + + { + .name = "ASCII", + .pull = ascii_pull, + .push = ascii_push + }, + { + .name = "646", + .pull = ascii_pull, + .push = ascii_push + }, + { + .name = "ISO-8859-1", + .pull = latin1_pull, + .push = latin1_push + }, +#ifdef DEVELOPER + { + .name = "WEIRD", + .pull = weird_pull, + .push = weird_push, + .samba_internal_charset = true + }, +#endif +#ifdef DARWINOS + { + .name = "MACOSXFS", + .pull = macosxfs_encoding_pull, + .push = macosxfs_encoding_push, + .samba_internal_charset = true + }, +#endif + { + .name = "UCS2-HEX", + .pull = ucs2hex_pull, + .push = ucs2hex_push, + .samba_internal_charset = true + } +}; + +#ifdef HAVE_NATIVE_ICONV +/* if there was an error then reset the internal state, + this ensures that we don't have a shift state remaining for + character sets like SJIS */ +static size_t sys_iconv(void *cd, + const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + size_t ret = iconv((iconv_t)cd, + discard_const_p(char *, inbuf), inbytesleft, + outbuf, outbytesleft); + if (ret == (size_t)-1) iconv(cd, NULL, NULL, NULL, NULL); + return ret; +} +#endif + +#ifdef HAVE_ICU_I18N +static size_t sys_uconv(void *cd, + const char **inbuf, + size_t *inbytesleft, + char **outbuf, + size_t *outbytesleft) +{ + UTransliterator *t = (UTransliterator *)cd; + size_t bufsize = *inbytesleft * 2; + UChar ustr[bufsize]; + UChar *up = NULL; + char *p = NULL; + int32_t ustrlen; + int32_t limit; + int32_t converted_len; + size_t inbuf_consumed; + size_t outbut_consumed; + UErrorCode ue; + + /* Convert from UTF8 to UCS2 */ + ue = 0; + up = u_strFromUTF8(ustr, /* dst */ + bufsize, /* dst buflen */ + &converted_len, /* dst written */ + *inbuf, /* src */ + *inbytesleft, /* src length */ + &ue); + if (up == NULL || U_FAILURE(ue)) { + return -1; + } + if (converted_len > bufsize) { + /* + * u_strFromUTF8() returns the required size in + * converted_len. In theory this should never overflow as the + * ustr[] array is allocated with a size twice as big as + * inbytesleft and converted_len should be equal to inbytesleft, + * but you never know... + */ + errno = EOVERFLOW; + return -1; + } + inbuf_consumed = converted_len; + + /* + * The following transliteration function takes two parameters, the + * length of the text to be converted (converted_len) and a limit which + * may be smaller then converted_len. We just set limit to converted_len + * and also ignore the value returned in limit. + */ + limit = converted_len; + + /* Inplace transliteration */ + utrans_transUChars(t, + ustr, /* text */ + &converted_len, /* text length */ + bufsize, /* text buflen */ + 0, /* start */ + &limit, /* limit */ + &ue); + if (U_FAILURE(ue)) { + return -1; + } + if (converted_len > bufsize) { + /* + * In theory this should never happen as the ustr[] array is + * allocated with a size twice as big as inbytesleft and + * converted_len should be equal to inbytesleft, but you never + * know... + */ + errno = EOVERFLOW; + return -1; + } + ustrlen = converted_len; + + /* Convert from UCS2 back to UTF8 */ + ue = 0; + p = u_strToUTF8(*outbuf, /* dst */ + *outbytesleft, /* dst buflen */ + &converted_len, /* dst required length */ + ustr, /* src */ + ustrlen, /* src length */ + &ue); + if (p == NULL || U_FAILURE(ue)) { + return -1; + } + + outbut_consumed = converted_len; + if (converted_len > *outbytesleft) { + /* + * The caller's result buffer is too small... + */ + outbut_consumed = *outbytesleft; + } + + *inbuf += inbuf_consumed; + *inbytesleft -= inbuf_consumed; + *outbuf += outbut_consumed; + *outbytesleft -= outbut_consumed; + + return converted_len; +} +#endif + +/** + * This is a simple portable iconv() implementation. + * + * It only knows about a very small number of character sets - just + * enough that Samba works on systems that don't have iconv. + **/ +_PUBLIC_ size_t smb_iconv(smb_iconv_t cd, + const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + /* in many cases we can go direct */ + if (cd->direct) { + return cd->direct(cd->cd_direct, + inbuf, inbytesleft, outbuf, outbytesleft); + } + + /* otherwise we have to do it chunks at a time */ + { +#ifndef SMB_ICONV_BUFSIZE +#define SMB_ICONV_BUFSIZE 2048 +#endif + size_t bufsize; + char cvtbuf[SMB_ICONV_BUFSIZE]; + + while (*inbytesleft > 0) { + char *bufp1 = cvtbuf; + const char *bufp2 = cvtbuf; + int saved_errno = errno; + bool pull_failed = false; + bufsize = SMB_ICONV_BUFSIZE; + + if (cd->pull(cd->cd_pull, + inbuf, inbytesleft, &bufp1, &bufsize) == -1 + && errno != E2BIG) { + saved_errno = errno; + pull_failed = true; + } + + bufsize = SMB_ICONV_BUFSIZE - bufsize; + + if (cd->push(cd->cd_push, + &bufp2, &bufsize, + outbuf, outbytesleft) == -1) { + return -1; + } else if (pull_failed) { + /* We want the pull errno if possible */ + errno = saved_errno; + return -1; + } + } + } + + return 0; +} + +static bool is_utf16(const char *name) +{ + return strcasecmp(name, "UCS-2LE") == 0 || + strcasecmp(name, "UTF-16LE") == 0; +} + +static int smb_iconv_t_destructor(smb_iconv_t hwd) +{ +#ifdef HAVE_ICU_I18N + /* + * This has to come first, as the cd_direct member won't be an iconv + * handle and must not be passed to iconv_close(). + */ + if (hwd->direct == sys_uconv) { + utrans_close(hwd->cd_direct); + return 0; + } +#endif +#ifdef HAVE_NATIVE_ICONV + if (hwd->cd_pull != NULL && hwd->cd_pull != (iconv_t)-1) + iconv_close(hwd->cd_pull); + if (hwd->cd_push != NULL && hwd->cd_push != (iconv_t)-1) + iconv_close(hwd->cd_push); + if (hwd->cd_direct != NULL && hwd->cd_direct != (iconv_t)-1) + iconv_close(hwd->cd_direct); +#endif + + return 0; +} + +_PUBLIC_ smb_iconv_t smb_iconv_open_ex(TALLOC_CTX *mem_ctx, const char *tocode, + const char *fromcode, bool use_builtin_handlers) +{ + smb_iconv_t ret; + const struct charset_functions *from=NULL, *to=NULL; + int i; + + ret = (smb_iconv_t)talloc_named(mem_ctx, + sizeof(*ret), + "iconv(%s,%s)", tocode, fromcode); + if (!ret) { + errno = ENOMEM; + return (smb_iconv_t)-1; + } + memset(ret, 0, sizeof(*ret)); + talloc_set_destructor(ret, smb_iconv_t_destructor); + + /* check for the simplest null conversion */ + if (strcmp(fromcode, tocode) == 0) { + ret->direct = iconv_copy; + return ret; + } + + /* check if we have a builtin function for this conversion */ + for (i=0;i<ARRAY_SIZE(builtin_functions);i++) { + if (strcasecmp(fromcode, builtin_functions[i].name) == 0) { + if (use_builtin_handlers || builtin_functions[i].samba_internal_charset) { + from = &builtin_functions[i]; + } + } + if (strcasecmp(tocode, builtin_functions[i].name) == 0) { + if (use_builtin_handlers || builtin_functions[i].samba_internal_charset) { + to = &builtin_functions[i]; + } + } + } + +#ifdef HAVE_NATIVE_ICONV + /* the from and to variables indicate a samba module or + * internal conversion, ret->pull and ret->push are + * initialised only in this block for iconv based + * conversions */ + + if (from == NULL) { + ret->cd_pull = iconv_open("UTF-16LE", fromcode); + if (ret->cd_pull == (iconv_t)-1) + ret->cd_pull = iconv_open("UCS-2LE", fromcode); + if (ret->cd_pull != (iconv_t)-1) { + ret->pull = sys_iconv; + } + } + + if (to == NULL) { + ret->cd_push = iconv_open(tocode, "UTF-16LE"); + if (ret->cd_push == (iconv_t)-1) + ret->cd_push = iconv_open(tocode, "UCS-2LE"); + if (ret->cd_push != (iconv_t)-1) { + ret->push = sys_iconv; + } + } +#endif + +#ifdef HAVE_ICU_I18N + if (strcasecmp(fromcode, "UTF8-NFD") == 0 && + strcasecmp(tocode, "UTF8-NFC") == 0) + { + U_STRING_DECL(t, "any-nfc", 7); + UErrorCode ue = 0; + + U_STRING_INIT(t, "any-nfc", 7); + + ret->cd_direct = utrans_openU(t, + strlen("any-nfc"), + UTRANS_FORWARD, + NULL, + 0, + NULL, + &ue); + if (U_FAILURE(ue)) { + return (smb_iconv_t)-1; + } + ret->direct = sys_uconv; + return ret; + } + + if (strcasecmp(fromcode, "UTF8-NFC") == 0 && + strcasecmp(tocode, "UTF8-NFD") == 0) + { + U_STRING_DECL(tname, "any-nfd", 7); + UErrorCode ue = 0; + + U_STRING_INIT(tname, "any-nfd", 7); + + ret->cd_direct = utrans_openU(tname, + 7, + UTRANS_FORWARD, + NULL, + 0, + NULL, + &ue); + if (U_FAILURE(ue)) { + return (smb_iconv_t)-1; + } + ret->direct = sys_uconv; + return ret; + } +#endif + + if (ret->pull == NULL && from == NULL) { + goto failed; + } + + if (ret->push == NULL && to == NULL) { + goto failed; + } + + /* check for conversion to/from ucs2 */ + if (is_utf16(fromcode) && to) { + ret->direct = to->push; + return ret; + } + if (is_utf16(tocode) && from) { + ret->direct = from->pull; + return ret; + } + +#ifdef HAVE_NATIVE_ICONV + if (is_utf16(fromcode)) { + ret->direct = sys_iconv; + ret->cd_direct = ret->cd_push; + ret->cd_push = NULL; + return ret; + } + if (is_utf16(tocode)) { + ret->direct = sys_iconv; + ret->cd_direct = ret->cd_pull; + ret->cd_pull = NULL; + return ret; + } +#endif + + /* the general case has to go via a buffer */ + if (!ret->pull) ret->pull = from->pull; + if (!ret->push) ret->push = to->push; + return ret; + +failed: + talloc_free(ret); + errno = EINVAL; + return (smb_iconv_t)-1; +} + +/* + simple iconv_open() wrapper + */ +_PUBLIC_ smb_iconv_t smb_iconv_open(const char *tocode, const char *fromcode) +{ + return smb_iconv_open_ex(NULL, tocode, fromcode, true); +} + +/* + simple iconv_close() wrapper +*/ +_PUBLIC_ int smb_iconv_close(smb_iconv_t cd) +{ + talloc_free(cd); + return 0; +} + + +/********************************************************************** + the following functions implement the builtin character sets in Samba + and also the "test" character sets that are designed to test + multi-byte character set support for english users +***********************************************************************/ + +/* + this takes an ASCII sequence and produces a UTF16 sequence + + The first 127 codepoints of latin1 matches the first 127 codepoints + of unicode, and so can be put into the first byte of UTF16LE + + */ + +static size_t ascii_pull(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + while (*inbytesleft >= 1 && *outbytesleft >= 2) { + if (((*inbuf)[0] & 0x7F) != (*inbuf)[0]) { + /* If this is multi-byte, then it isn't legal ASCII */ + errno = EILSEQ; + return -1; + } + (*outbuf)[0] = (*inbuf)[0]; + (*outbuf)[1] = 0; + (*inbytesleft) -= 1; + (*outbytesleft) -= 2; + (*inbuf) += 1; + (*outbuf) += 2; + } + + if (*inbytesleft > 0) { + errno = E2BIG; + return -1; + } + + return 0; +} + +/* + this takes a UTF16 sequence and produces an ASCII sequence + + The first 127 codepoints of ASCII matches the first 127 codepoints + of unicode, and so can be read directly from the first byte of UTF16LE + + */ +static size_t ascii_push(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + int ir_count=0; + + while (*inbytesleft >= 2 && *outbytesleft >= 1) { + if (((*inbuf)[0] & 0x7F) != (*inbuf)[0] || + (*inbuf)[1] != 0) { + /* If this is multi-byte, then it isn't legal ASCII */ + errno = EILSEQ; + return -1; + } + (*outbuf)[0] = (*inbuf)[0]; + (*inbytesleft) -= 2; + (*outbytesleft) -= 1; + (*inbuf) += 2; + (*outbuf) += 1; + } + + if (*inbytesleft == 1) { + errno = EINVAL; + return -1; + } + + if (*inbytesleft > 1) { + errno = E2BIG; + return -1; + } + + return ir_count; +} + +/* + this takes a latin1/ISO-8859-1 sequence and produces a UTF16 sequence + + The first 256 codepoints of latin1 matches the first 256 codepoints + of unicode, and so can be put into the first byte of UTF16LE + + */ +static size_t latin1_pull(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + while (*inbytesleft >= 1 && *outbytesleft >= 2) { + (*outbuf)[0] = (*inbuf)[0]; + (*outbuf)[1] = 0; + (*inbytesleft) -= 1; + (*outbytesleft) -= 2; + (*inbuf) += 1; + (*outbuf) += 2; + } + + if (*inbytesleft > 0) { + errno = E2BIG; + return -1; + } + + return 0; +} + +/* + this takes a UTF16 sequence and produces a latin1/ISO-8859-1 sequence + + The first 256 codepoints of latin1 matches the first 256 codepoints + of unicode, and so can be read directly from the first byte of UTF16LE + + */ +static size_t latin1_push(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + int ir_count=0; + + while (*inbytesleft >= 2 && *outbytesleft >= 1) { + (*outbuf)[0] = (*inbuf)[0]; + if ((*inbuf)[1] != 0) { + /* If this is multi-byte, then it isn't legal latin1 */ + errno = EILSEQ; + return -1; + } + (*inbytesleft) -= 2; + (*outbytesleft) -= 1; + (*inbuf) += 2; + (*outbuf) += 1; + } + + if (*inbytesleft == 1) { + errno = EINVAL; + return -1; + } + + if (*inbytesleft > 1) { + errno = E2BIG; + return -1; + } + + return ir_count; +} + +static size_t ucs2hex_pull(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + while (*inbytesleft >= 1 && *outbytesleft >= 2) { + uint8_t hi = 0, lo = 0; + bool ok; + + if ((*inbuf)[0] != '@') { + /* seven bit ascii case */ + (*outbuf)[0] = (*inbuf)[0]; + (*outbuf)[1] = 0; + (*inbytesleft) -= 1; + (*outbytesleft) -= 2; + (*inbuf) += 1; + (*outbuf) += 2; + continue; + } + /* it's a hex character */ + if (*inbytesleft < 5) { + errno = EINVAL; + return -1; + } + + ok = hex_byte(&(*inbuf)[1], &hi) && hex_byte(&(*inbuf)[3], &lo); + if (!ok) { + errno = EILSEQ; + return -1; + } + + (*outbuf)[0] = lo; + (*outbuf)[1] = hi; + (*inbytesleft) -= 5; + (*outbytesleft) -= 2; + (*inbuf) += 5; + (*outbuf) += 2; + } + + if (*inbytesleft > 0) { + errno = E2BIG; + return -1; + } + + return 0; +} + +static size_t ucs2hex_push(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + while (*inbytesleft >= 2 && *outbytesleft >= 1) { + char buf[6]; + + if ((*inbuf)[1] == 0 && + ((*inbuf)[0] & 0x80) == 0 && + (*inbuf)[0] != '@') { + (*outbuf)[0] = (*inbuf)[0]; + (*inbytesleft) -= 2; + (*outbytesleft) -= 1; + (*inbuf) += 2; + (*outbuf) += 1; + continue; + } + if (*outbytesleft < 5) { + errno = E2BIG; + return -1; + } + snprintf(buf, 6, "@%04x", SVAL(*inbuf, 0)); + memcpy(*outbuf, buf, 5); + (*inbytesleft) -= 2; + (*outbytesleft) -= 5; + (*inbuf) += 2; + (*outbuf) += 5; + } + + if (*inbytesleft == 1) { + errno = EINVAL; + return -1; + } + + if (*inbytesleft > 1) { + errno = E2BIG; + return -1; + } + + return 0; +} + +static size_t iconv_swab(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + int n; + + n = MIN(*inbytesleft, *outbytesleft); + + swab(*inbuf, *outbuf, (n&~1)); + if (n&1) { + (*outbuf)[n-1] = 0; + } + + (*inbytesleft) -= n; + (*outbytesleft) -= n; + (*inbuf) += n; + (*outbuf) += n; + + if (*inbytesleft > 0) { + errno = E2BIG; + return -1; + } + + return 0; +} + + +static size_t iconv_copy(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + int n; + + n = MIN(*inbytesleft, *outbytesleft); + + memmove(*outbuf, *inbuf, n); + + (*inbytesleft) -= n; + (*outbytesleft) -= n; + (*inbuf) += n; + (*outbuf) += n; + + if (*inbytesleft > 0) { + errno = E2BIG; + return -1; + } + + return 0; +} + +/* + this takes a UTF8 sequence and produces a UTF16 sequence + */ +static size_t utf8_pull(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + size_t in_left=*inbytesleft, out_left=*outbytesleft; + const uint8_t *c = (const uint8_t *)*inbuf; + uint8_t *uc = (uint8_t *)*outbuf; + + while (in_left >= 1 && out_left >= 2) { + if ((c[0] & 0x80) == 0) { + uc[0] = c[0]; + uc[1] = 0; + c += 1; + in_left -= 1; + out_left -= 2; + uc += 2; + continue; + } + + if ((c[0] & 0xe0) == 0xc0) { + if (in_left < 2 || + (c[1] & 0xc0) != 0x80) { + errno = EILSEQ; + goto error; + } + uc[1] = (c[0]>>2) & 0x7; + uc[0] = (c[0]<<6) | (c[1]&0x3f); + if (uc[1] == 0 && uc[0] < 0x80) { + /* this should have been a single byte */ + errno = EILSEQ; + goto error; + } + c += 2; + in_left -= 2; + out_left -= 2; + uc += 2; + continue; + } + + if ((c[0] & 0xf0) == 0xe0) { + unsigned int codepoint; + if (in_left < 3 || + (c[1] & 0xc0) != 0x80 || + (c[2] & 0xc0) != 0x80) { + errno = EILSEQ; + goto error; + } + codepoint = ((c[2] & 0x3f) | + ((c[1] & 0x3f) << 6) | + ((c[0] & 0x0f) << 12)); + + if (codepoint < 0x800) { + /* this should be a 1 or 2 byte sequence */ + errno = EILSEQ; + goto error; + } + if (codepoint >= 0xd800 && codepoint <= 0xdfff) { + /* + * This is an invalid codepoint, per + * RFC3629, as it encodes part of a + * UTF-16 surrogate pair for a + * character over U+10000, which ought + * to have been encoded as a four byte + * utf-8 sequence. + * + * Prior to Vista, Windows might + * sometimes produce invalid strings + * where a utf-16 sequence containing + * surrogate pairs was converted + * "verbatim" into utf-8, instead of + * encoding the actual codepoint. This + * format is sometimes called "WTF-8". + * + * If we were to support that, we'd + * have a branch here for the case + * where the codepoint is between + * 0xd800 and 0xdbff (a "high + * surrogate"), and read a *six* + * character sequence from there which + * would include a low surrogate. But + * that would undermine the + * hard-learnt principle that each + * character should only have one + * encoding. + */ + errno = EILSEQ; + goto error; + } + + uc[0] = codepoint & 0xff; + uc[1] = codepoint >> 8; + c += 3; + in_left -= 3; + out_left -= 2; + uc += 2; + continue; + } + + if ((c[0] & 0xf8) == 0xf0) { + unsigned int codepoint; + if (in_left < 4 || + (c[1] & 0xc0) != 0x80 || + (c[2] & 0xc0) != 0x80 || + (c[3] & 0xc0) != 0x80) { + errno = EILSEQ; + goto error; + } + codepoint = + (c[3]&0x3f) | + ((c[2]&0x3f)<<6) | + ((c[1]&0x3f)<<12) | + ((c[0]&0x7)<<18); + if (codepoint < 0x10000) { + /* reject UTF-8 characters that are not + minimally packed */ + errno = EILSEQ; + goto error; + } + if (codepoint > 0x10ffff) { + /* + * Unicode stops at 0x10ffff, and if + * we ignore that, we'll end up + * encoding the wrong characters in + * the surrogate pair. + */ + errno = EILSEQ; + goto error; + } + + codepoint -= 0x10000; + + if (out_left < 4) { + errno = E2BIG; + goto error; + } + + uc[0] = (codepoint>>10) & 0xFF; + uc[1] = (codepoint>>18) | 0xd8; + uc[2] = codepoint & 0xFF; + uc[3] = ((codepoint>>8) & 0x3) | 0xdc; + c += 4; + in_left -= 4; + out_left -= 4; + uc += 4; + continue; + } + + /* we don't handle 5 byte sequences */ + errno = EINVAL; + goto error; + } + + if (in_left > 0) { + errno = E2BIG; + goto error; + } + + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)c; + *outbuf = (char *)uc; + return 0; + +error: + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)c; + *outbuf = (char *)uc; + return -1; +} + + +/* + this takes a UTF16 sequence and produces a UTF8 sequence + */ +static size_t utf8_push(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + size_t in_left=*inbytesleft, out_left=*outbytesleft; + uint8_t *c = (uint8_t *)*outbuf; + const uint8_t *uc = (const uint8_t *)*inbuf; + + while (in_left >= 2 && out_left >= 1) { + unsigned int codepoint; + + if (uc[1] == 0 && !(uc[0] & 0x80)) { + /* simplest case */ + c[0] = uc[0]; + in_left -= 2; + out_left -= 1; + uc += 2; + c += 1; + continue; + } + + if ((uc[1]&0xf8) == 0) { + /* next simplest case */ + if (out_left < 2) { + errno = E2BIG; + goto error; + } + c[0] = 0xc0 | (uc[0]>>6) | (uc[1]<<2); + c[1] = 0x80 | (uc[0] & 0x3f); + in_left -= 2; + out_left -= 2; + uc += 2; + c += 2; + continue; + } + + if ((uc[1] & 0xfc) == 0xdc) { + errno = EILSEQ; +#ifndef HAVE_ICONV_ERRNO_ILLEGAL_MULTIBYTE + if (in_left < 4) { + errno = EINVAL; + } +#endif + goto error; + } + + if ((uc[1] & 0xfc) != 0xd8) { + codepoint = uc[0] | (uc[1]<<8); + if (out_left < 3) { + errno = E2BIG; + goto error; + } + c[0] = 0xe0 | (codepoint >> 12); + c[1] = 0x80 | ((codepoint >> 6) & 0x3f); + c[2] = 0x80 | (codepoint & 0x3f); + + in_left -= 2; + out_left -= 3; + uc += 2; + c += 3; + continue; + } + + /* its the first part of a 4 byte sequence */ + if (in_left < 4) { + errno = EINVAL; + goto error; + } + if ((uc[3] & 0xfc) != 0xdc) { + errno = EILSEQ; + goto error; + } + codepoint = 0x10000 + (uc[2] | ((uc[3] & 0x3)<<8) | + (uc[0]<<10) | ((uc[1] & 0x3)<<18)); + + if (out_left < 4) { + errno = E2BIG; + goto error; + } + c[0] = 0xf0 | (codepoint >> 18); + c[1] = 0x80 | ((codepoint >> 12) & 0x3f); + c[2] = 0x80 | ((codepoint >> 6) & 0x3f); + c[3] = 0x80 | (codepoint & 0x3f); + + in_left -= 4; + out_left -= 4; + uc += 4; + c += 4; + } + + if (in_left == 1) { + errno = EINVAL; + goto error; + } + + if (in_left > 1) { + errno = E2BIG; + goto error; + } + + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)uc; + *outbuf = (char *)c; + + return 0; + +error: + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)uc; + *outbuf = (char *)c; + return -1; +} + + +/* + this takes a UTF16 munged sequence, modifies it according to the + string2key rules, and produces a UTF16 sequence + +The rules are: + + 1) any 0x0000 characters are mapped to 0x0001 + + 2) convert any instance of 0xD800 - 0xDBFF (high surrogate) + without an immediately following 0xDC00 - 0x0xDFFF (low surrogate) to + U+FFFD (OBJECT REPLACEMENT CHARACTER). + + 3) the same for any low surrogate that was not preceded by a high surrogate. + + */ +static size_t utf16_munged_pull(void *cd, const char **inbuf, size_t *inbytesleft, + char **outbuf, size_t *outbytesleft) +{ + size_t in_left=*inbytesleft, out_left=*outbytesleft; + uint8_t *c = (uint8_t *)*outbuf; + const uint8_t *uc = (const uint8_t *)*inbuf; + + while (in_left >= 2 && out_left >= 2) { + unsigned int codepoint = uc[0] | (uc[1]<<8); + + if (codepoint == 0) { + codepoint = 1; + } + + if ((codepoint & 0xfc00) == 0xd800) { + /* a high surrogate */ + unsigned int codepoint2; + if (in_left < 4) { + codepoint = 0xfffd; + goto codepoint16; + } + codepoint2 = uc[2] | (uc[3]<<8); + if ((codepoint2 & 0xfc00) != 0xdc00) { + /* high surrogate not followed by low + surrogate: convert to 0xfffd */ + codepoint = 0xfffd; + goto codepoint16; + } + if (out_left < 4) { + errno = E2BIG; + goto error; + } + memcpy(c, uc, 4); + in_left -= 4; + out_left -= 4; + uc += 4; + c += 4; + continue; + } + + if ((codepoint & 0xfc00) == 0xdc00) { + /* low surrogate not preceded by high + surrogate: convert to 0xfffd */ + codepoint = 0xfffd; + } + + codepoint16: + c[0] = codepoint & 0xFF; + c[1] = (codepoint>>8) & 0xFF; + + in_left -= 2; + out_left -= 2; + uc += 2; + c += 2; + continue; + } + + if (in_left == 1) { + errno = EINVAL; + goto error; + } + + if (in_left > 1) { + errno = E2BIG; + goto error; + } + + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)uc; + *outbuf = (char *)c; + + return 0; + +error: + *inbytesleft = in_left; + *outbytesleft = out_left; + *inbuf = (const char *)uc; + *outbuf = (char *)c; + return -1; +} + + + |