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Diffstat (limited to 'contrib/gcc/cppcharset.c')
-rw-r--r-- | contrib/gcc/cppcharset.c | 1411 |
1 files changed, 1411 insertions, 0 deletions
diff --git a/contrib/gcc/cppcharset.c b/contrib/gcc/cppcharset.c new file mode 100644 index 0000000..a6a65ed --- /dev/null +++ b/contrib/gcc/cppcharset.c @@ -0,0 +1,1411 @@ +/* CPP Library - charsets + Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004 + Free Software Foundation, Inc. + + Broken out of c-lex.c Apr 2003, adding valid C99 UCN ranges. + +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 2, 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, write to the Free Software +Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#include "config.h" +#include "system.h" +#include "cpplib.h" +#include "cpphash.h" +#include "cppucnid.h" + +/* Character set handling for C-family languages. + + Terminological note: In what follows, "charset" or "character set" + will be taken to mean both an abstract set of characters and an + encoding for that set. + + The C99 standard discusses two character sets: source and execution. + The source character set is used for internal processing in translation + phases 1 through 4; the execution character set is used thereafter. + Both are required by 5.2.1.2p1 to be multibyte encodings, not wide + character encodings (see 3.7.2, 3.7.3 for the standardese meanings + of these terms). Furthermore, the "basic character set" (listed in + 5.2.1p3) is to be encoded in each with values one byte wide, and is + to appear in the initial shift state. + + It is not explicitly mentioned, but there is also a "wide execution + character set" used to encode wide character constants and wide + string literals; this is supposed to be the result of applying the + standard library function mbstowcs() to an equivalent narrow string + (6.4.5p5). However, the behavior of hexadecimal and octal + \-escapes is at odds with this; they are supposed to be translated + directly to wchar_t values (6.4.4.4p5,6). + + The source character set is not necessarily the character set used + to encode physical source files on disk; translation phase 1 converts + from whatever that encoding is to the source character set. + + The presence of universal character names in C99 (6.4.3 et seq.) + forces the source character set to be isomorphic to ISO 10646, + that is, Unicode. There is no such constraint on the execution + character set; note also that the conversion from source to + execution character set does not occur for identifiers (5.1.1.2p1#5). + + For convenience of implementation, the source character set's + encoding of the basic character set should be identical to the + execution character set OF THE HOST SYSTEM's encoding of the basic + character set, and it should not be a state-dependent encoding. + + cpplib uses UTF-8 or UTF-EBCDIC for the source character set, + depending on whether the host is based on ASCII or EBCDIC (see + respectively Unicode section 2.3/ISO10646 Amendment 2, and Unicode + Technical Report #16). With limited exceptions, it relies on the + system library's iconv() primitive to do charset conversion + (specified in SUSv2). */ + +#if !HAVE_ICONV +/* Make certain that the uses of iconv(), iconv_open(), iconv_close() + below, which are guarded only by if statements with compile-time + constant conditions, do not cause link errors. */ +#define iconv_open(x, y) (errno = EINVAL, (iconv_t)-1) +#define iconv(a,b,c,d,e) (errno = EINVAL, (size_t)-1) +#define iconv_close(x) (void)0 +#define ICONV_CONST +#endif + +#if HOST_CHARSET == HOST_CHARSET_ASCII +#define SOURCE_CHARSET "UTF-8" +#elif HOST_CHARSET == HOST_CHARSET_EBCDIC +#define SOURCE_CHARSET "UTF-EBCDIC" +#else +#error "Unrecognized basic host character set" +#endif + +#ifndef EILSEQ +#define EILSEQ EINVAL +#endif + +/* This structure is used for a resizable string buffer throughout. */ +/* Don't call it strbuf, as that conflicts with unistd.h on systems + such as DYNIX/ptx where unistd.h includes stropts.h. */ +struct _cpp_strbuf +{ + uchar *text; + size_t asize; + size_t len; +}; + +/* This is enough to hold any string that fits on a single 80-column + line, even if iconv quadruples its size (e.g. conversion from + ASCII to UTF-32) rounded up to a power of two. */ +#define OUTBUF_BLOCK_SIZE 256 + +/* Conversions between UTF-8 and UTF-16/32 are implemented by custom + logic. This is because a depressing number of systems lack iconv, + or have have iconv libraries that do not do these conversions, so + we need a fallback implementation for them. To ensure the fallback + doesn't break due to neglect, it is used on all systems. + + UTF-32 encoding is nice and simple: a four-byte binary number, + constrained to the range 00000000-7FFFFFFF to avoid questions of + signedness. We do have to cope with big- and little-endian + variants. + + UTF-16 encoding uses two-byte binary numbers, again in big- and + little-endian variants, for all values in the 00000000-0000FFFF + range. Values in the 00010000-0010FFFF range are encoded as pairs + of two-byte numbers, called "surrogate pairs": given a number S in + this range, it is mapped to a pair (H, L) as follows: + + H = (S - 0x10000) / 0x400 + 0xD800 + L = (S - 0x10000) % 0x400 + 0xDC00 + + Two-byte values in the D800...DFFF range are ill-formed except as a + component of a surrogate pair. Even if the encoding within a + two-byte value is little-endian, the H member of the surrogate pair + comes first. + + There is no way to encode values in the 00110000-7FFFFFFF range, + which is not currently a problem as there are no assigned code + points in that range; however, the author expects that it will + eventually become necessary to abandon UTF-16 due to this + limitation. Note also that, because of these pairs, UTF-16 does + not meet the requirements of the C standard for a wide character + encoding (see 3.7.3 and 6.4.4.4p11). + + UTF-8 encoding looks like this: + + value range encoded as + 00000000-0000007F 0xxxxxxx + 00000080-000007FF 110xxxxx 10xxxxxx + 00000800-0000FFFF 1110xxxx 10xxxxxx 10xxxxxx + 00010000-001FFFFF 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx + 00200000-03FFFFFF 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx + 04000000-7FFFFFFF 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx + + Values in the 0000D800 ... 0000DFFF range (surrogates) are invalid, + which means that three-byte sequences ED xx yy, with A0 <= xx <= BF, + never occur. Note also that any value that can be encoded by a + given row of the table can also be encoded by all successive rows, + but this is not done; only the shortest possible encoding for any + given value is valid. For instance, the character 07C0 could be + encoded as any of DF 80, E0 9F 80, F0 80 9F 80, F8 80 80 9F 80, or + FC 80 80 80 9F 80. Only the first is valid. + + An implementation note: the transformation from UTF-16 to UTF-8, or + vice versa, is easiest done by using UTF-32 as an intermediary. */ + +/* Internal primitives which go from an UTF-8 byte stream to native-endian + UTF-32 in a cppchar_t, or vice versa; this avoids an extra marshal/unmarshal + operation in several places below. */ +static inline int +one_utf8_to_cppchar (const uchar **inbufp, size_t *inbytesleftp, + cppchar_t *cp) +{ + static const uchar masks[6] = { 0x7F, 0x1F, 0x0F, 0x07, 0x02, 0x01 }; + static const uchar patns[6] = { 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC }; + + cppchar_t c; + const uchar *inbuf = *inbufp; + size_t nbytes, i; + + if (*inbytesleftp < 1) + return EINVAL; + + c = *inbuf; + if (c < 0x80) + { + *cp = c; + *inbytesleftp -= 1; + *inbufp += 1; + return 0; + } + + /* The number of leading 1-bits in the first byte indicates how many + bytes follow. */ + for (nbytes = 2; nbytes < 7; nbytes++) + if ((c & ~masks[nbytes-1]) == patns[nbytes-1]) + goto found; + return EILSEQ; + found: + + if (*inbytesleftp < nbytes) + return EINVAL; + + c = (c & masks[nbytes-1]); + inbuf++; + for (i = 1; i < nbytes; i++) + { + cppchar_t n = *inbuf++; + if ((n & 0xC0) != 0x80) + return EILSEQ; + c = ((c << 6) + (n & 0x3F)); + } + + /* Make sure the shortest possible encoding was used. */ + if (c <= 0x7F && nbytes > 1) return EILSEQ; + if (c <= 0x7FF && nbytes > 2) return EILSEQ; + if (c <= 0xFFFF && nbytes > 3) return EILSEQ; + if (c <= 0x1FFFFF && nbytes > 4) return EILSEQ; + if (c <= 0x3FFFFFF && nbytes > 5) return EILSEQ; + + /* Make sure the character is valid. */ + if (c > 0x7FFFFFFF || (c >= 0xD800 && c <= 0xDFFF)) return EILSEQ; + + *cp = c; + *inbufp = inbuf; + *inbytesleftp -= nbytes; + return 0; +} + +static inline int +one_cppchar_to_utf8 (cppchar_t c, uchar **outbufp, size_t *outbytesleftp) +{ + static const uchar masks[6] = { 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC }; + static const uchar limits[6] = { 0x80, 0xE0, 0xF0, 0xF8, 0xFC, 0xFE }; + size_t nbytes; + uchar buf[6], *p = &buf[6]; + uchar *outbuf = *outbufp; + + nbytes = 1; + if (c < 0x80) + *--p = c; + else + { + do + { + *--p = ((c & 0x3F) | 0x80); + c >>= 6; + nbytes++; + } + while (c >= 0x3F || (c & limits[nbytes-1])); + *--p = (c | masks[nbytes-1]); + } + + if (*outbytesleftp < nbytes) + return E2BIG; + + while (p < &buf[6]) + *outbuf++ = *p++; + *outbytesleftp -= nbytes; + *outbufp = outbuf; + return 0; +} + +/* The following four functions transform one character between the two + encodings named in the function name. All have the signature + int (*)(iconv_t bigend, const uchar **inbufp, size_t *inbytesleftp, + uchar **outbufp, size_t *outbytesleftp) + + BIGEND must have the value 0 or 1, coerced to (iconv_t); it is + interpreted as a boolean indicating whether big-endian or + little-endian encoding is to be used for the member of the pair + that is not UTF-8. + + INBUFP, INBYTESLEFTP, OUTBUFP, OUTBYTESLEFTP work exactly as they + do for iconv. + + The return value is either 0 for success, or an errno value for + failure, which may be E2BIG (need more space), EILSEQ (ill-formed + input sequence), ir EINVAL (incomplete input sequence). */ + +static inline int +one_utf8_to_utf32 (iconv_t bigend, const uchar **inbufp, size_t *inbytesleftp, + uchar **outbufp, size_t *outbytesleftp) +{ + uchar *outbuf; + cppchar_t s = 0; + int rval; + + /* Check for space first, since we know exactly how much we need. */ + if (*outbytesleftp < 4) + return E2BIG; + + rval = one_utf8_to_cppchar (inbufp, inbytesleftp, &s); + if (rval) + return rval; + + outbuf = *outbufp; + outbuf[bigend ? 3 : 0] = (s & 0x000000FF); + outbuf[bigend ? 2 : 1] = (s & 0x0000FF00) >> 8; + outbuf[bigend ? 1 : 2] = (s & 0x00FF0000) >> 16; + outbuf[bigend ? 0 : 3] = (s & 0xFF000000) >> 24; + + *outbufp += 4; + *outbytesleftp -= 4; + return 0; +} + +static inline int +one_utf32_to_utf8 (iconv_t bigend, const uchar **inbufp, size_t *inbytesleftp, + uchar **outbufp, size_t *outbytesleftp) +{ + cppchar_t s; + int rval; + const uchar *inbuf; + + if (*inbytesleftp < 4) + return EINVAL; + + inbuf = *inbufp; + + s = inbuf[bigend ? 0 : 3] << 24; + s += inbuf[bigend ? 1 : 2] << 16; + s += inbuf[bigend ? 2 : 1] << 8; + s += inbuf[bigend ? 3 : 0]; + + if (s >= 0x7FFFFFFF || (s >= 0xD800 && s <= 0xDFFF)) + return EILSEQ; + + rval = one_cppchar_to_utf8 (s, outbufp, outbytesleftp); + if (rval) + return rval; + + *inbufp += 4; + *inbytesleftp -= 4; + return 0; +} + +static inline int +one_utf8_to_utf16 (iconv_t bigend, const uchar **inbufp, size_t *inbytesleftp, + uchar **outbufp, size_t *outbytesleftp) +{ + int rval; + cppchar_t s = 0; + const uchar *save_inbuf = *inbufp; + size_t save_inbytesleft = *inbytesleftp; + uchar *outbuf = *outbufp; + + rval = one_utf8_to_cppchar (inbufp, inbytesleftp, &s); + if (rval) + return rval; + + if (s > 0x0010FFFF) + { + *inbufp = save_inbuf; + *inbytesleftp = save_inbytesleft; + return EILSEQ; + } + + if (s < 0xFFFF) + { + if (*outbytesleftp < 2) + { + *inbufp = save_inbuf; + *inbytesleftp = save_inbytesleft; + return E2BIG; + } + outbuf[bigend ? 1 : 0] = (s & 0x00FF); + outbuf[bigend ? 0 : 1] = (s & 0xFF00) >> 8; + + *outbufp += 2; + *outbytesleftp -= 2; + return 0; + } + else + { + cppchar_t hi, lo; + + if (*outbytesleftp < 4) + { + *inbufp = save_inbuf; + *inbytesleftp = save_inbytesleft; + return E2BIG; + } + + hi = (s - 0x10000) / 0x400 + 0xD800; + lo = (s - 0x10000) % 0x400 + 0xDC00; + + /* Even if we are little-endian, put the high surrogate first. + ??? Matches practice? */ + outbuf[bigend ? 1 : 0] = (hi & 0x00FF); + outbuf[bigend ? 0 : 1] = (hi & 0xFF00) >> 8; + outbuf[bigend ? 3 : 2] = (lo & 0x00FF); + outbuf[bigend ? 2 : 3] = (lo & 0xFF00) >> 8; + + *outbufp += 4; + *outbytesleftp -= 4; + return 0; + } +} + +static inline int +one_utf16_to_utf8 (iconv_t bigend, const uchar **inbufp, size_t *inbytesleftp, + uchar **outbufp, size_t *outbytesleftp) +{ + cppchar_t s; + const uchar *inbuf = *inbufp; + int rval; + + if (*inbytesleftp < 2) + return EINVAL; + s = inbuf[bigend ? 0 : 1] << 8; + s += inbuf[bigend ? 1 : 0]; + + /* Low surrogate without immediately preceding high surrogate is invalid. */ + if (s >= 0xDC00 && s <= 0xDFFF) + return EILSEQ; + /* High surrogate must have a following low surrogate. */ + else if (s >= 0xD800 && s <= 0xDBFF) + { + cppchar_t hi = s, lo; + if (*inbytesleftp < 4) + return EINVAL; + + lo = inbuf[bigend ? 2 : 3] << 8; + lo += inbuf[bigend ? 3 : 2]; + + if (lo < 0xDC00 || lo > 0xDFFF) + return EILSEQ; + + s = (hi - 0xD800) * 0x400 + (lo - 0xDC00) + 0x10000; + } + + rval = one_cppchar_to_utf8 (s, outbufp, outbytesleftp); + if (rval) + return rval; + + /* Success - update the input pointers (one_cppchar_to_utf8 has done + the output pointers for us). */ + if (s <= 0xFFFF) + { + *inbufp += 2; + *inbytesleftp -= 2; + } + else + { + *inbufp += 4; + *inbytesleftp -= 4; + } + return 0; +} + +/* Helper routine for the next few functions. The 'const' on + one_conversion means that we promise not to modify what function is + pointed to, which lets the inliner see through it. */ + +static inline bool +conversion_loop (int (*const one_conversion)(iconv_t, const uchar **, size_t *, + uchar **, size_t *), + iconv_t cd, const uchar *from, size_t flen, struct _cpp_strbuf *to) +{ + const uchar *inbuf; + uchar *outbuf; + size_t inbytesleft, outbytesleft; + int rval; + + inbuf = from; + inbytesleft = flen; + outbuf = to->text + to->len; + outbytesleft = to->asize - to->len; + + for (;;) + { + do + rval = one_conversion (cd, &inbuf, &inbytesleft, + &outbuf, &outbytesleft); + while (inbytesleft && !rval); + + if (__builtin_expect (inbytesleft == 0, 1)) + { + to->len = to->asize - outbytesleft; + return true; + } + if (rval != E2BIG) + { + errno = rval; + return false; + } + + outbytesleft += OUTBUF_BLOCK_SIZE; + to->asize += OUTBUF_BLOCK_SIZE; + to->text = xrealloc (to->text, to->asize); + outbuf = to->text + to->asize - outbytesleft; + } +} + + +/* These functions convert entire strings between character sets. + They all have the signature + + bool (*)(iconv_t cd, const uchar *from, size_t flen, struct _cpp_strbuf *to); + + The input string FROM is converted as specified by the function + name plus the iconv descriptor CD (which may be fake), and the + result appended to TO. On any error, false is returned, otherwise true. */ + +/* These four use the custom conversion code above. */ +static bool +convert_utf8_utf16 (iconv_t cd, const uchar *from, size_t flen, + struct _cpp_strbuf *to) +{ + return conversion_loop (one_utf8_to_utf16, cd, from, flen, to); +} + +static bool +convert_utf8_utf32 (iconv_t cd, const uchar *from, size_t flen, + struct _cpp_strbuf *to) +{ + return conversion_loop (one_utf8_to_utf32, cd, from, flen, to); +} + +static bool +convert_utf16_utf8 (iconv_t cd, const uchar *from, size_t flen, + struct _cpp_strbuf *to) +{ + return conversion_loop (one_utf16_to_utf8, cd, from, flen, to); +} + +static bool +convert_utf32_utf8 (iconv_t cd, const uchar *from, size_t flen, + struct _cpp_strbuf *to) +{ + return conversion_loop (one_utf32_to_utf8, cd, from, flen, to); +} + +/* Identity conversion, used when we have no alternative. */ +static bool +convert_no_conversion (iconv_t cd ATTRIBUTE_UNUSED, + const uchar *from, size_t flen, struct _cpp_strbuf *to) +{ + if (to->len + flen > to->asize) + { + to->asize = to->len + flen; + to->text = xrealloc (to->text, to->asize); + } + memcpy (to->text + to->len, from, flen); + to->len += flen; + return true; +} + +/* And this one uses the system iconv primitive. It's a little + different, since iconv's interface is a little different. */ +#if HAVE_ICONV +static bool +convert_using_iconv (iconv_t cd, const uchar *from, size_t flen, + struct _cpp_strbuf *to) +{ + ICONV_CONST char *inbuf; + char *outbuf; + size_t inbytesleft, outbytesleft; + + /* Reset conversion descriptor and check that it is valid. */ + if (iconv (cd, 0, 0, 0, 0) == (size_t)-1) + return false; + + inbuf = (ICONV_CONST char *)from; + inbytesleft = flen; + outbuf = (char *)to->text + to->len; + outbytesleft = to->asize - to->len; + + for (;;) + { + iconv (cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft); + if (__builtin_expect (inbytesleft == 0, 1)) + { + to->len = to->asize - outbytesleft; + return true; + } + if (errno != E2BIG) + return false; + + outbytesleft += OUTBUF_BLOCK_SIZE; + to->asize += OUTBUF_BLOCK_SIZE; + to->text = xrealloc (to->text, to->asize); + outbuf = (char *)to->text + to->asize - outbytesleft; + } +} +#else +#define convert_using_iconv 0 /* prevent undefined symbol error below */ +#endif + +/* Arrange for the above custom conversion logic to be used automatically + when conversion between a suitable pair of character sets is requested. */ + +#define APPLY_CONVERSION(CONVERTER, FROM, FLEN, TO) \ + CONVERTER.func (CONVERTER.cd, FROM, FLEN, TO) + +struct conversion +{ + const char *pair; + convert_f func; + iconv_t fake_cd; +}; +static const struct conversion conversion_tab[] = { + { "UTF-8/UTF-32LE", convert_utf8_utf32, (iconv_t)0 }, + { "UTF-8/UTF-32BE", convert_utf8_utf32, (iconv_t)1 }, + { "UTF-8/UTF-16LE", convert_utf8_utf16, (iconv_t)0 }, + { "UTF-8/UTF-16BE", convert_utf8_utf16, (iconv_t)1 }, + { "UTF-32LE/UTF-8", convert_utf32_utf8, (iconv_t)0 }, + { "UTF-32BE/UTF-8", convert_utf32_utf8, (iconv_t)1 }, + { "UTF-16LE/UTF-8", convert_utf16_utf8, (iconv_t)0 }, + { "UTF-16BE/UTF-8", convert_utf16_utf8, (iconv_t)1 }, +}; + +/* Subroutine of cpp_init_iconv: initialize and return a + cset_converter structure for conversion from FROM to TO. If + iconv_open() fails, issue an error and return an identity + converter. Silently return an identity converter if FROM and TO + are identical. */ +static struct cset_converter +init_iconv_desc (cpp_reader *pfile, const char *to, const char *from) +{ + struct cset_converter ret; + char *pair; + size_t i; + + if (!strcasecmp (to, from)) + { + ret.func = convert_no_conversion; + ret.cd = (iconv_t) -1; + return ret; + } + + pair = alloca(strlen(to) + strlen(from) + 2); + + strcpy(pair, from); + strcat(pair, "/"); + strcat(pair, to); + for (i = 0; i < ARRAY_SIZE (conversion_tab); i++) + if (!strcasecmp (pair, conversion_tab[i].pair)) + { + ret.func = conversion_tab[i].func; + ret.cd = conversion_tab[i].fake_cd; + return ret; + } + + /* No custom converter - try iconv. */ + if (HAVE_ICONV) + { + ret.func = convert_using_iconv; + ret.cd = iconv_open (to, from); + + if (ret.cd == (iconv_t) -1) + { + if (errno == EINVAL) + cpp_error (pfile, CPP_DL_ERROR, /* XXX should be DL_SORRY */ + "conversion from %s to %s not supported by iconv", + from, to); + else + cpp_errno (pfile, CPP_DL_ERROR, "iconv_open"); + + ret.func = convert_no_conversion; + } + } + else + { + cpp_error (pfile, CPP_DL_ERROR, /* XXX should be DL_SORRY */ + "no iconv implementation, cannot convert from %s to %s", + from, to); + ret.func = convert_no_conversion; + ret.cd = (iconv_t) -1; + } + return ret; +} + +/* If charset conversion is requested, initialize iconv(3) descriptors + for conversion from the source character set to the execution + character sets. If iconv is not present in the C library, and + conversion is requested, issue an error. */ + +void +cpp_init_iconv (cpp_reader *pfile) +{ + const char *ncset = CPP_OPTION (pfile, narrow_charset); + const char *wcset = CPP_OPTION (pfile, wide_charset); + const char *default_wcset; + + bool be = CPP_OPTION (pfile, bytes_big_endian); + + if (CPP_OPTION (pfile, wchar_precision) >= 32) + default_wcset = be ? "UTF-32BE" : "UTF-32LE"; + else if (CPP_OPTION (pfile, wchar_precision) >= 16) + default_wcset = be ? "UTF-16BE" : "UTF-16LE"; + else + /* This effectively means that wide strings are not supported, + so don't do any conversion at all. */ + default_wcset = SOURCE_CHARSET; + + if (!ncset) + ncset = SOURCE_CHARSET; + if (!wcset) + wcset = default_wcset; + + pfile->narrow_cset_desc = init_iconv_desc (pfile, ncset, SOURCE_CHARSET); + pfile->wide_cset_desc = init_iconv_desc (pfile, wcset, SOURCE_CHARSET); +} + +void +_cpp_destroy_iconv (cpp_reader *pfile) +{ + if (HAVE_ICONV) + { + if (pfile->narrow_cset_desc.func == convert_using_iconv) + iconv_close (pfile->narrow_cset_desc.cd); + if (pfile->wide_cset_desc.func == convert_using_iconv) + iconv_close (pfile->wide_cset_desc.cd); + } +} + + +/* Utility routine that computes a mask of the form 0000...111... with + WIDTH 1-bits. */ +static inline size_t +width_to_mask (size_t width) +{ + width = MIN (width, BITS_PER_CPPCHAR_T); + if (width >= CHAR_BIT * sizeof (size_t)) + return ~(size_t) 0; + else + return ((size_t) 1 << width) - 1; +} + + + +/* Returns 1 if C is valid in an identifier, 2 if C is valid except at + the start of an identifier, and 0 if C is not valid in an + identifier. We assume C has already gone through the checks of + _cpp_valid_ucn. The algorithm is a simple binary search on the + table defined in cppucnid.h. */ + +static int +ucn_valid_in_identifier (cpp_reader *pfile, cppchar_t c) +{ + int mn, mx, md; + + mn = -1; + mx = ARRAY_SIZE (ucnranges); + while (mx - mn > 1) + { + md = (mn + mx) / 2; + if (c < ucnranges[md].lo) + mx = md; + else if (c > ucnranges[md].hi) + mn = md; + else + goto found; + } + return 0; + + found: + /* When -pedantic, we require the character to have been listed by + the standard for the current language. Otherwise, we accept the + union of the acceptable sets for C++98 and C99. */ + if (CPP_PEDANTIC (pfile) + && ((CPP_OPTION (pfile, c99) && !(ucnranges[md].flags & C99)) + || (CPP_OPTION (pfile, cplusplus) + && !(ucnranges[md].flags & CXX)))) + return 0; + + /* In C99, UCN digits may not begin identifiers. */ + if (CPP_OPTION (pfile, c99) && (ucnranges[md].flags & DIG)) + return 2; + + return 1; +} + +/* [lex.charset]: The character designated by the universal character + name \UNNNNNNNN is that character whose character short name in + ISO/IEC 10646 is NNNNNNNN; the character designated by the + universal character name \uNNNN is that character whose character + short name in ISO/IEC 10646 is 0000NNNN. If the hexadecimal value + for a universal character name is less than 0x20 or in the range + 0x7F-0x9F (inclusive), or if the universal character name + designates a character in the basic source character set, then the + program is ill-formed. + + *PSTR must be preceded by "\u" or "\U"; it is assumed that the + buffer end is delimited by a non-hex digit. Returns zero if UCNs + are not part of the relevant standard, or if the string beginning + at *PSTR doesn't syntactically match the form 'NNNN' or 'NNNNNNNN'. + + Otherwise the nonzero value of the UCN, whether valid or invalid, + is returned. Diagnostics are emitted for invalid values. PSTR + is updated to point one beyond the UCN, or to the syntactically + invalid character. + + IDENTIFIER_POS is 0 when not in an identifier, 1 for the start of + an identifier, or 2 otherwise. +*/ + +cppchar_t +_cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr, + const uchar *limit, int identifier_pos) +{ + cppchar_t result, c; + unsigned int length; + const uchar *str = *pstr; + const uchar *base = str - 2; + + if (!CPP_OPTION (pfile, cplusplus) && !CPP_OPTION (pfile, c99)) + cpp_error (pfile, CPP_DL_WARNING, + "universal character names are only valid in C++ and C99"); + else if (CPP_WTRADITIONAL (pfile) && identifier_pos == 0) + cpp_error (pfile, CPP_DL_WARNING, + "the meaning of '\\%c' is different in traditional C", + (int) str[-1]); + + if (str[-1] == 'u') + length = 4; + else if (str[-1] == 'U') + length = 8; + else + abort(); + + result = 0; + do + { + c = *str; + if (!ISXDIGIT (c)) + break; + str++; + result = (result << 4) + hex_value (c); + } + while (--length && str < limit); + + *pstr = str; + if (length) + { + /* We'll error when we try it out as the start of an identifier. */ + cpp_error (pfile, CPP_DL_ERROR, + "incomplete universal character name %.*s", + (int) (str - base), base); + result = 1; + } + /* The standard permits $, @ and ` to be specified as UCNs. We use + hex escapes so that this also works with EBCDIC hosts. */ + else if ((result < 0xa0 + && (result != 0x24 && result != 0x40 && result != 0x60)) + || (result & 0x80000000) + || (result >= 0xD800 && result <= 0xDFFF)) + { + cpp_error (pfile, CPP_DL_ERROR, + "%.*s is not a valid universal character", + (int) (str - base), base); + result = 1; + } + else if (identifier_pos) + { + int validity = ucn_valid_in_identifier (pfile, result); + + if (validity == 0) + cpp_error (pfile, CPP_DL_ERROR, + "universal character %.*s is not valid in an identifier", + (int) (str - base), base); + else if (validity == 2 && identifier_pos == 1) + cpp_error (pfile, CPP_DL_ERROR, + "universal character %.*s is not valid at the start of an identifier", + (int) (str - base), base); + } + + if (result == 0) + result = 1; + + return result; +} + +/* Convert an UCN, pointed to by FROM, to UTF-8 encoding, then translate + it to the execution character set and write the result into TBUF. + An advanced pointer is returned. Issues all relevant diagnostics. */ + + +static const uchar * +convert_ucn (cpp_reader *pfile, const uchar *from, const uchar *limit, + struct _cpp_strbuf *tbuf, bool wide) +{ + cppchar_t ucn; + uchar buf[6]; + uchar *bufp = buf; + size_t bytesleft = 6; + int rval; + struct cset_converter cvt + = wide ? pfile->wide_cset_desc : pfile->narrow_cset_desc; + + from++; /* Skip u/U. */ + ucn = _cpp_valid_ucn (pfile, &from, limit, 0); + + rval = one_cppchar_to_utf8 (ucn, &bufp, &bytesleft); + if (rval) + { + errno = rval; + cpp_errno (pfile, CPP_DL_ERROR, + "converting UCN to source character set"); + } + else if (!APPLY_CONVERSION (cvt, buf, 6 - bytesleft, tbuf)) + cpp_errno (pfile, CPP_DL_ERROR, + "converting UCN to execution character set"); + + return from; +} + +static void +emit_numeric_escape (cpp_reader *pfile, cppchar_t n, + struct _cpp_strbuf *tbuf, bool wide) +{ + if (wide) + { + /* We have to render this into the target byte order, which may not + be our byte order. */ + bool bigend = CPP_OPTION (pfile, bytes_big_endian); + size_t width = CPP_OPTION (pfile, wchar_precision); + size_t cwidth = CPP_OPTION (pfile, char_precision); + size_t cmask = width_to_mask (cwidth); + size_t nbwc = width / cwidth; + size_t i; + size_t off = tbuf->len; + cppchar_t c; + + if (tbuf->len + nbwc > tbuf->asize) + { + tbuf->asize += OUTBUF_BLOCK_SIZE; + tbuf->text = xrealloc (tbuf->text, tbuf->asize); + } + + for (i = 0; i < nbwc; i++) + { + c = n & cmask; + n >>= cwidth; + tbuf->text[off + (bigend ? nbwc - i - 1 : i)] = c; + } + tbuf->len += nbwc; + } + else + { + if (tbuf->len + 1 > tbuf->asize) + { + tbuf->asize += OUTBUF_BLOCK_SIZE; + tbuf->text = xrealloc (tbuf->text, tbuf->asize); + } + tbuf->text[tbuf->len++] = n; + } +} + +/* Convert a hexadecimal escape, pointed to by FROM, to the execution + character set and write it into the string buffer TBUF. Returns an + advanced pointer, and issues diagnostics as necessary. + No character set translation occurs; this routine always produces the + execution-set character with numeric value equal to the given hex + number. You can, e.g. generate surrogate pairs this way. */ +static const uchar * +convert_hex (cpp_reader *pfile, const uchar *from, const uchar *limit, + struct _cpp_strbuf *tbuf, bool wide) +{ + cppchar_t c, n = 0, overflow = 0; + int digits_found = 0; + size_t width = (wide ? CPP_OPTION (pfile, wchar_precision) + : CPP_OPTION (pfile, char_precision)); + size_t mask = width_to_mask (width); + + if (CPP_WTRADITIONAL (pfile)) + cpp_error (pfile, CPP_DL_WARNING, + "the meaning of '\\x' is different in traditional C"); + + from++; /* Skip 'x'. */ + while (from < limit) + { + c = *from; + if (! hex_p (c)) + break; + from++; + overflow |= n ^ (n << 4 >> 4); + n = (n << 4) + hex_value (c); + digits_found = 1; + } + + if (!digits_found) + { + cpp_error (pfile, CPP_DL_ERROR, + "\\x used with no following hex digits"); + return from; + } + + if (overflow | (n != (n & mask))) + { + cpp_error (pfile, CPP_DL_PEDWARN, + "hex escape sequence out of range"); + n &= mask; + } + + emit_numeric_escape (pfile, n, tbuf, wide); + + return from; +} + +/* Convert an octal escape, pointed to by FROM, to the execution + character set and write it into the string buffer TBUF. Returns an + advanced pointer, and issues diagnostics as necessary. + No character set translation occurs; this routine always produces the + execution-set character with numeric value equal to the given octal + number. */ +static const uchar * +convert_oct (cpp_reader *pfile, const uchar *from, const uchar *limit, + struct _cpp_strbuf *tbuf, bool wide) +{ + size_t count = 0; + cppchar_t c, n = 0; + size_t width = (wide ? CPP_OPTION (pfile, wchar_precision) + : CPP_OPTION (pfile, char_precision)); + size_t mask = width_to_mask (width); + bool overflow = false; + + while (from < limit && count++ < 3) + { + c = *from; + if (c < '0' || c > '7') + break; + from++; + overflow |= n ^ (n << 3 >> 3); + n = (n << 3) + c - '0'; + } + + if (n != (n & mask)) + { + cpp_error (pfile, CPP_DL_PEDWARN, + "octal escape sequence out of range"); + n &= mask; + } + + emit_numeric_escape (pfile, n, tbuf, wide); + + return from; +} + +/* Convert an escape sequence (pointed to by FROM) to its value on + the target, and to the execution character set. Do not scan past + LIMIT. Write the converted value into TBUF. Returns an advanced + pointer. Handles all relevant diagnostics. */ +static const uchar * +convert_escape (cpp_reader *pfile, const uchar *from, const uchar *limit, + struct _cpp_strbuf *tbuf, bool wide) +{ + /* Values of \a \b \e \f \n \r \t \v respectively. */ +#if HOST_CHARSET == HOST_CHARSET_ASCII + static const uchar charconsts[] = { 7, 8, 27, 12, 10, 13, 9, 11 }; +#elif HOST_CHARSET == HOST_CHARSET_EBCDIC + static const uchar charconsts[] = { 47, 22, 39, 12, 21, 13, 5, 11 }; +#else +#error "unknown host character set" +#endif + + uchar c; + struct cset_converter cvt + = wide ? pfile->wide_cset_desc : pfile->narrow_cset_desc; + + c = *from; + switch (c) + { + /* UCNs, hex escapes, and octal escapes are processed separately. */ + case 'u': case 'U': + return convert_ucn (pfile, from, limit, tbuf, wide); + + case 'x': + return convert_hex (pfile, from, limit, tbuf, wide); + break; + + case '0': case '1': case '2': case '3': + case '4': case '5': case '6': case '7': + return convert_oct (pfile, from, limit, tbuf, wide); + + /* Various letter escapes. Get the appropriate host-charset + value into C. */ + case '\\': case '\'': case '"': case '?': break; + + case '(': case '{': case '[': case '%': + /* '\(', etc, can be used at the beginning of a line in a long + string split onto multiple lines with \-newline, to prevent + Emacs or other text editors from getting confused. '\%' can + be used to prevent SCCS from mangling printf format strings. */ + if (CPP_PEDANTIC (pfile)) + goto unknown; + break; + + case 'b': c = charconsts[1]; break; + case 'f': c = charconsts[3]; break; + case 'n': c = charconsts[4]; break; + case 'r': c = charconsts[5]; break; + case 't': c = charconsts[6]; break; + case 'v': c = charconsts[7]; break; + + case 'a': + if (CPP_WTRADITIONAL (pfile)) + cpp_error (pfile, CPP_DL_WARNING, + "the meaning of '\\a' is different in traditional C"); + c = charconsts[0]; + break; + + case 'e': case 'E': + if (CPP_PEDANTIC (pfile)) + cpp_error (pfile, CPP_DL_PEDWARN, + "non-ISO-standard escape sequence, '\\%c'", (int) c); + c = charconsts[2]; + break; + + default: + unknown: + if (ISGRAPH (c)) + cpp_error (pfile, CPP_DL_PEDWARN, + "unknown escape sequence '\\%c'", (int) c); + else + cpp_error (pfile, CPP_DL_PEDWARN, + "unknown escape sequence: '\\%03o'", (int) c); + } + + /* Now convert what we have to the execution character set. */ + if (!APPLY_CONVERSION (cvt, &c, 1, tbuf)) + cpp_errno (pfile, CPP_DL_ERROR, + "converting escape sequence to execution character set"); + + return from + 1; +} + +/* FROM is an array of cpp_string structures of length COUNT. These + are to be converted from the source to the execution character set, + escape sequences translated, and finally all are to be + concatenated. WIDE indicates whether or not to produce a wide + string. The result is written into TO. Returns true for success, + false for failure. */ +bool +cpp_interpret_string (cpp_reader *pfile, const cpp_string *from, size_t count, + cpp_string *to, bool wide) +{ + struct _cpp_strbuf tbuf; + const uchar *p, *base, *limit; + size_t i; + struct cset_converter cvt + = wide ? pfile->wide_cset_desc : pfile->narrow_cset_desc; + + tbuf.asize = MAX (OUTBUF_BLOCK_SIZE, from->len); + tbuf.text = xmalloc (tbuf.asize); + tbuf.len = 0; + + for (i = 0; i < count; i++) + { + p = from[i].text; + if (*p == 'L') p++; + p++; /* Skip leading quote. */ + limit = from[i].text + from[i].len - 1; /* Skip trailing quote. */ + + for (;;) + { + base = p; + while (p < limit && *p != '\\') + p++; + if (p > base) + { + /* We have a run of normal characters; these can be fed + directly to convert_cset. */ + if (!APPLY_CONVERSION (cvt, base, p - base, &tbuf)) + goto fail; + } + if (p == limit) + break; + + p = convert_escape (pfile, p + 1, limit, &tbuf, wide); + } + } + /* NUL-terminate the 'to' buffer and translate it to a cpp_string + structure. */ + emit_numeric_escape (pfile, 0, &tbuf, wide); + tbuf.text = xrealloc (tbuf.text, tbuf.len); + to->text = tbuf.text; + to->len = tbuf.len; + return true; + + fail: + cpp_errno (pfile, CPP_DL_ERROR, "converting to execution character set"); + free (tbuf.text); + return false; +} + +/* Subroutine of do_line and do_linemarker. Convert escape sequences + in a string, but do not perform character set conversion. */ +bool +_cpp_interpret_string_notranslate (cpp_reader *pfile, const cpp_string *in, + cpp_string *out) +{ + struct cset_converter save_narrow_cset_desc = pfile->narrow_cset_desc; + bool retval; + + pfile->narrow_cset_desc.func = convert_no_conversion; + pfile->narrow_cset_desc.cd = (iconv_t) -1; + + retval = cpp_interpret_string (pfile, in, 1, out, false); + + pfile->narrow_cset_desc = save_narrow_cset_desc; + return retval; +} + + +/* Subroutine of cpp_interpret_charconst which performs the conversion + to a number, for narrow strings. STR is the string structure returned + by cpp_interpret_string. PCHARS_SEEN and UNSIGNEDP are as for + cpp_interpret_charconst. */ +static cppchar_t +narrow_str_to_charconst (cpp_reader *pfile, cpp_string str, + unsigned int *pchars_seen, int *unsignedp) +{ + size_t width = CPP_OPTION (pfile, char_precision); + size_t max_chars = CPP_OPTION (pfile, int_precision) / width; + size_t mask = width_to_mask (width); + size_t i; + cppchar_t result, c; + bool unsigned_p; + + /* The value of a multi-character character constant, or a + single-character character constant whose representation in the + execution character set is more than one byte long, is + implementation defined. This implementation defines it to be the + number formed by interpreting the byte sequence in memory as a + big-endian binary number. If overflow occurs, the high bytes are + lost, and a warning is issued. + + We don't want to process the NUL terminator handed back by + cpp_interpret_string. */ + result = 0; + for (i = 0; i < str.len - 1; i++) + { + c = str.text[i] & mask; + if (width < BITS_PER_CPPCHAR_T) + result = (result << width) | c; + else + result = c; + } + + if (i > max_chars) + { + i = max_chars; + cpp_error (pfile, CPP_DL_WARNING, + "character constant too long for its type"); + } + else if (i > 1 && CPP_OPTION (pfile, warn_multichar)) + cpp_error (pfile, CPP_DL_WARNING, "multi-character character constant"); + + /* Multichar constants are of type int and therefore signed. */ + if (i > 1) + unsigned_p = 0; + else + unsigned_p = CPP_OPTION (pfile, unsigned_char); + + /* Truncate the constant to its natural width, and simultaneously + sign- or zero-extend to the full width of cppchar_t. + For single-character constants, the value is WIDTH bits wide. + For multi-character constants, the value is INT_PRECISION bits wide. */ + if (i > 1) + width = CPP_OPTION (pfile, int_precision); + if (width < BITS_PER_CPPCHAR_T) + { + mask = ((cppchar_t) 1 << width) - 1; + if (unsigned_p || !(result & (1 << (width - 1)))) + result &= mask; + else + result |= ~mask; + } + *pchars_seen = i; + *unsignedp = unsigned_p; + return result; +} + +/* Subroutine of cpp_interpret_charconst which performs the conversion + to a number, for wide strings. STR is the string structure returned + by cpp_interpret_string. PCHARS_SEEN and UNSIGNEDP are as for + cpp_interpret_charconst. */ +static cppchar_t +wide_str_to_charconst (cpp_reader *pfile, cpp_string str, + unsigned int *pchars_seen, int *unsignedp) +{ + bool bigend = CPP_OPTION (pfile, bytes_big_endian); + size_t width = CPP_OPTION (pfile, wchar_precision); + size_t cwidth = CPP_OPTION (pfile, char_precision); + size_t mask = width_to_mask (width); + size_t cmask = width_to_mask (cwidth); + size_t nbwc = width / cwidth; + size_t off, i; + cppchar_t result = 0, c; + + /* This is finicky because the string is in the target's byte order, + which may not be our byte order. Only the last character, ignoring + the NUL terminator, is relevant. */ + off = str.len - (nbwc * 2); + result = 0; + for (i = 0; i < nbwc; i++) + { + c = bigend ? str.text[off + i] : str.text[off + nbwc - i - 1]; + result = (result << cwidth) | (c & cmask); + } + + /* Wide character constants have type wchar_t, and a single + character exactly fills a wchar_t, so a multi-character wide + character constant is guaranteed to overflow. */ + if (off > 0) + cpp_error (pfile, CPP_DL_WARNING, + "character constant too long for its type"); + + /* Truncate the constant to its natural width, and simultaneously + sign- or zero-extend to the full width of cppchar_t. */ + if (width < BITS_PER_CPPCHAR_T) + { + if (CPP_OPTION (pfile, unsigned_wchar) || !(result & (1 << (width - 1)))) + result &= mask; + else + result |= ~mask; + } + + *unsignedp = CPP_OPTION (pfile, unsigned_wchar); + *pchars_seen = 1; + return result; +} + +/* Interpret a (possibly wide) character constant in TOKEN. + PCHARS_SEEN points to a variable that is filled in with the number + of characters seen, and UNSIGNEDP to a variable that indicates + whether the result has signed type. */ +cppchar_t +cpp_interpret_charconst (cpp_reader *pfile, const cpp_token *token, + unsigned int *pchars_seen, int *unsignedp) +{ + cpp_string str = { 0, 0 }; + bool wide = (token->type == CPP_WCHAR); + cppchar_t result; + + /* an empty constant will appear as L'' or '' */ + if (token->val.str.len == (size_t) (2 + wide)) + { + cpp_error (pfile, CPP_DL_ERROR, "empty character constant"); + return 0; + } + else if (!cpp_interpret_string (pfile, &token->val.str, 1, &str, wide)) + return 0; + + if (wide) + result = wide_str_to_charconst (pfile, str, pchars_seen, unsignedp); + else + result = narrow_str_to_charconst (pfile, str, pchars_seen, unsignedp); + + if (str.text != token->val.str.text) + free ((void *)str.text); + + return result; +} + +uchar * +_cpp_convert_input (cpp_reader *pfile, const char *input_charset, + uchar *input, size_t size, size_t len, off_t *st_size) +{ + struct cset_converter input_cset; + struct _cpp_strbuf to; + + input_cset = init_iconv_desc (pfile, SOURCE_CHARSET, input_charset); + if (input_cset.func == convert_no_conversion) + { + to.text = input; + to.asize = size; + to.len = len; + } + else + { + to.asize = MAX (65536, len); + to.text = xmalloc (to.asize); + to.len = 0; + + if (!APPLY_CONVERSION (input_cset, input, len, &to)) + cpp_error (pfile, CPP_DL_ERROR, + "failure to convert %s to %s", + CPP_OPTION (pfile, input_charset), SOURCE_CHARSET); + + free (input); + } + + /* Clean up the mess. */ + if (input_cset.func == convert_using_iconv) + iconv_close (input_cset.cd); + + /* Resize buffer if we allocated substantially too much, or if we + haven't enough space for the \n-terminator. */ + if (to.len + 4096 < to.asize || to.len >= to.asize) + to.text = xrealloc (to.text, to.len + 1); + + to.text[to.len] = '\n'; + *st_size = to.len; + return to.text; +} + +const char * +_cpp_default_encoding (void) +{ + const char *current_encoding = NULL; + +#if defined (HAVE_LOCALE_H) && defined (HAVE_LANGINFO_CODESET) + setlocale (LC_CTYPE, ""); + current_encoding = nl_langinfo (CODESET); +#endif + if (current_encoding == NULL || *current_encoding == '\0') + current_encoding = SOURCE_CHARSET; + + return current_encoding; +} |