5beadb33d9
2003-07-07 Andrew Pinski <pinskia@physics.uc.edu> * cppcharset.c (ICONV_CONST): Define iff !HAVE_ICONV. (convert_cset): Change inbuf to type ICONV_CONST char. * Makefile.in (LIBS): Add LIBICONV. From-SVN: r69029
893 lines
28 KiB
C
893 lines
28 KiB
C
/* CPP Library - charsets
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Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003
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Free Software Foundation, Inc.
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Broken out of c-lex.c Apr 2003, adding valid C99 UCN ranges.
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "cpplib.h"
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#include "cpphash.h"
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#include "cppucnid.h"
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/* Character set handling for C-family languages.
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Terminological note: In what follows, "charset" or "character set"
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will be taken to mean both an abstract set of characters and an
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encoding for that set.
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The C99 standard discusses two character sets: source and execution.
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The source character set is used for internal processing in translation
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phases 1 through 4; the execution character set is used thereafter.
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Both are required by 5.2.1.2p1 to be multibyte encodings, not wide
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character encodings (see 3.7.2, 3.7.3 for the standardese meanings
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of these terms). Furthermore, the "basic character set" (listed in
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5.2.1p3) is to be encoded in each with values one byte wide, and is
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to appear in the initial shift state.
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It is not explicitly mentioned, but there is also a "wide execution
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character set" used to encode wide character constants and wide
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string literals; this is supposed to be the result of applying the
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standard library function mbstowcs() to an equivalent narrow string
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(6.4.5p5). However, the behavior of hexadecimal and octal
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\-escapes is at odds with this; they are supposed to be translated
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directly to wchar_t values (6.4.4.4p5,6).
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The source character set is not necessarily the character set used
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to encode physical source files on disk; translation phase 1 converts
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from whatever that encoding is to the source character set.
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The presence of universal character names in C99 (6.4.3 et seq.)
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forces the source character set to be isomorphic to ISO 10646,
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that is, Unicode. There is no such constraint on the execution
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character set; note also that the conversion from source to
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execution character set does not occur for identifiers (5.1.1.2p1#5).
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For convenience of implementation, the source character set's
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encoding of the basic character set should be identical to the
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execution character set OF THE HOST SYSTEM's encoding of the basic
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character set, and it should not be a state-dependent encoding.
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cpplib uses UTF-8 or UTF-EBCDIC for the source character set,
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depending on whether the host is based on ASCII or EBCDIC (see
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respectively Unicode section 2.3/ISO10646 Amendment 2, and Unicode
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Technical Report #16). It relies on the system library's iconv()
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primitive to do charset conversion (specified in SUSv2). If this
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primitive is not present, the source and execution character sets
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must be identical and are limited to the basic ASCII or EBCDIC
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range, and wide characters are implemented by padding narrow
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characters to the size of wchar_t. */
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#if !HAVE_ICONV
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/* Make certain that the uses of iconv(), iconv_open(), iconv_close()
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below, which are guarded only by if statements with compile-time
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constant conditions, do not cause link errors. */
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#define iconv_open(x, y) (errno = EINVAL, (iconv_t)-1)
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#define iconv(a,b,c,d,e) (errno = EINVAL, (size_t)-1)
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#define iconv_close(x) 0
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#define ICONV_CONST
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#endif
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#if HOST_CHARSET == HOST_CHARSET_ASCII
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#define SOURCE_CHARSET "UTF-8"
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#elif HOST_CHARSET == HOST_CHARSET_EBCDIC
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#define SOURCE_CHARSET "UTF-EBCDIC"
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#else
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#error "Unrecognized basic host character set"
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#endif
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/* This structure is used for a resizable string buffer, mostly by
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convert_cset and cpp_interpret_string. */
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struct strbuf
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{
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uchar *text;
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size_t asize;
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size_t len;
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};
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/* This is enough to hold any string that fits on a single 80-column
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line, even if iconv quadruples its size (e.g. conversion from
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ASCII to UCS-4) rounded up to a power of two. */
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#define OUTBUF_BLOCK_SIZE 256
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/* Subroutine of cpp_init_iconv: initialize and return an iconv
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descriptor for conversion from FROM to TO. If iconv_open() fails,
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issue an error and return (iconv_t) -1. Silently return
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(iconv_t) -1 if FROM and TO are identical. */
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static iconv_t
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init_iconv_desc (cpp_reader *pfile, const char *to, const char *from)
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{
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iconv_t dsc;
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if (!strcmp (to, from))
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return (iconv_t) -1;
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dsc = iconv_open (to, from);
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if (dsc == (iconv_t) -1)
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{
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if (errno == EINVAL)
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cpp_error (pfile, DL_ERROR, /* XXX should be DL_SORRY */
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"conversion from %s to %s not supported by iconv",
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from, to);
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else
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cpp_errno (pfile, DL_ERROR, "iconv_open");
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}
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return dsc;
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}
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/* If charset conversion is requested, initialize iconv(3) descriptors
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for conversion from the source character set to the execution
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character sets. If iconv is not present in the C library, and
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conversion is requested, issue an error. */
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void
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cpp_init_iconv (cpp_reader *pfile)
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{
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const char *ncset = CPP_OPTION (pfile, narrow_charset);
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const char *wcset = CPP_OPTION (pfile, wide_charset);
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const char *default_wcset;
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bool be = CPP_OPTION (pfile, bytes_big_endian);
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if (CPP_OPTION (pfile, wchar_precision) >= 32)
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default_wcset = be ? "UCS-4BE" : "UCS-4LE";
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else if (CPP_OPTION (pfile, wchar_precision) >= 16)
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default_wcset = be ? "UCS-2BE" : "UCS-2LE";
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else
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/* This effectively means that wide strings are not supported,
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so don't do any conversion at all. */
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default_wcset = SOURCE_CHARSET;
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if (!HAVE_ICONV)
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{
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if (ncset && strcmp (ncset, SOURCE_CHARSET))
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cpp_error (pfile, DL_ERROR, /* XXX should be DL_SORRY */
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"no iconv implementation, cannot convert to %s", ncset);
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if (wcset && strcmp (wcset, default_wcset))
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cpp_error (pfile, DL_ERROR, /* XXX should be DL_SORRY */
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"no iconv implementation, cannot convert to %s", wcset);
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}
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else
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{
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if (!ncset)
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ncset = SOURCE_CHARSET;
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if (!wcset)
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wcset = default_wcset;
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pfile->narrow_cset_desc = init_iconv_desc (pfile, ncset, SOURCE_CHARSET);
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pfile->wide_cset_desc = init_iconv_desc (pfile, wcset, SOURCE_CHARSET);
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}
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}
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void
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_cpp_destroy_iconv (cpp_reader *pfile)
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{
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if (HAVE_ICONV)
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{
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if (pfile->narrow_cset_desc != (iconv_t) -1)
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iconv_close (pfile->narrow_cset_desc);
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if (pfile->wide_cset_desc != (iconv_t) -1)
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iconv_close (pfile->wide_cset_desc);
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}
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}
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/* iconv(3) utility wrapper. Convert the string FROM, of length FLEN,
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according to the iconv descriptor CD. The result is appended to
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the string buffer TO. If DESC is (iconv_t)-1 or iconv is not
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available, the string is simply copied into TO.
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Returns true on success, false on error. */
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static bool
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convert_cset (iconv_t cd, const uchar *from, size_t flen, struct strbuf *to)
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{
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if (!HAVE_ICONV || cd == (iconv_t)-1)
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{
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if (to->len + flen > to->asize)
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{
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to->asize = to->len + flen;
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to->text = xrealloc (to->text, to->asize);
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}
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memcpy (to->text + to->len, from, flen);
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to->len += flen;
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return true;
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}
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else
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{
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ICONV_CONST char *inbuf;
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char *outbuf;
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size_t inbytesleft, outbytesleft;
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/* Reset conversion descriptor and check that it is valid. */
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if (iconv (cd, 0, 0, 0, 0) == (size_t)-1)
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return false;
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inbuf = (ICONV_CONST char *)from;
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inbytesleft = flen;
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outbuf = (char *)to->text + to->len;
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outbytesleft = to->asize - to->len;
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for (;;)
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{
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iconv (cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft);
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if (__builtin_expect (inbytesleft == 0, 1))
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{
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to->len = to->asize - outbytesleft;
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return true;
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}
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if (errno != E2BIG)
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return false;
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outbytesleft += OUTBUF_BLOCK_SIZE;
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to->asize += OUTBUF_BLOCK_SIZE;
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to->text = xrealloc (to->text, to->asize);
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outbuf = (char *)to->text + to->asize - outbytesleft;
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}
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}
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}
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/* Utility routine that computes a mask of the form 0000...111... with
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WIDTH 1-bits. */
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static inline size_t
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width_to_mask (size_t width)
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{
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width = MIN (width, BITS_PER_CPPCHAR_T);
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if (width >= CHAR_BIT * sizeof (size_t))
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return ~(size_t) 0;
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else
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return ((size_t) 1 << width) - 1;
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}
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/* Returns 1 if C is valid in an identifier, 2 if C is valid except at
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the start of an identifier, and 0 if C is not valid in an
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identifier. We assume C has already gone through the checks of
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_cpp_valid_ucn. The algorithm is a simple binary search on the
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table defined in cppucnid.h. */
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static int
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ucn_valid_in_identifier (cpp_reader *pfile, cppchar_t c)
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{
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int mn, mx, md;
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mn = -1;
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mx = ARRAY_SIZE (ucnranges);
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while (mx - mn > 1)
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{
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md = (mn + mx) / 2;
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if (c < ucnranges[md].lo)
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mx = md;
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else if (c > ucnranges[md].hi)
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mn = md;
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else
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goto found;
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}
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return 0;
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found:
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/* When -pedantic, we require the character to have been listed by
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the standard for the current language. Otherwise, we accept the
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union of the acceptable sets for C++98 and C99. */
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if (CPP_PEDANTIC (pfile)
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&& ((CPP_OPTION (pfile, c99) && !(ucnranges[md].flags & C99))
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|| (CPP_OPTION (pfile, cplusplus)
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&& !(ucnranges[md].flags & CXX))))
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return 0;
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/* In C99, UCN digits may not begin identifiers. */
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if (CPP_OPTION (pfile, c99) && (ucnranges[md].flags & DIG))
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return 2;
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return 1;
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}
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/* [lex.charset]: The character designated by the universal character
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name \UNNNNNNNN is that character whose character short name in
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ISO/IEC 10646 is NNNNNNNN; the character designated by the
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universal character name \uNNNN is that character whose character
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short name in ISO/IEC 10646 is 0000NNNN. If the hexadecimal value
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for a universal character name is less than 0x20 or in the range
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0x7F-0x9F (inclusive), or if the universal character name
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designates a character in the basic source character set, then the
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program is ill-formed.
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*PSTR must be preceded by "\u" or "\U"; it is assumed that the
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buffer end is delimited by a non-hex digit. Returns zero if UCNs
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are not part of the relevant standard, or if the string beginning
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at *PSTR doesn't syntactically match the form 'NNNN' or 'NNNNNNNN'.
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Otherwise the nonzero value of the UCN, whether valid or invalid,
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is returned. Diagnostics are emitted for invalid values. PSTR
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is updated to point one beyond the UCN, or to the syntactically
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invalid character.
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IDENTIFIER_POS is 0 when not in an identifier, 1 for the start of
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an identifier, or 2 otherwise.
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*/
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cppchar_t
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_cpp_valid_ucn (cpp_reader *pfile, const uchar **pstr,
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const uchar *limit, int identifier_pos)
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{
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cppchar_t result, c;
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unsigned int length;
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const uchar *str = *pstr;
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const uchar *base = str - 2;
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if (!CPP_OPTION (pfile, cplusplus) && !CPP_OPTION (pfile, c99))
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cpp_error (pfile, DL_WARNING,
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"universal character names are only valid in C++ and C99");
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else if (CPP_WTRADITIONAL (pfile) && identifier_pos == 0)
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cpp_error (pfile, DL_WARNING,
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"the meaning of '\\%c' is different in traditional C",
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(int) str[-1]);
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if (str[-1] == 'u')
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length = 4;
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else if (str[-1] == 'U')
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length = 8;
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else
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abort();
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result = 0;
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do
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{
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c = *str;
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if (!ISXDIGIT (c))
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break;
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str++;
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result = (result << 4) + hex_value (c);
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}
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while (--length && str < limit);
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*pstr = str;
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if (length)
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{
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/* We'll error when we try it out as the start of an identifier. */
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cpp_error (pfile, DL_ERROR, "incomplete universal character name %.*s",
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(int) (str - base), base);
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result = 1;
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}
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/* The standard permits $, @ and ` to be specified as UCNs. We use
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hex escapes so that this also works with EBCDIC hosts. */
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else if ((result < 0xa0
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&& (result != 0x24 && result != 0x40 && result != 0x60))
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|| (result & 0x80000000)
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|| (result >= 0xD800 && result <= 0xDFFF))
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{
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cpp_error (pfile, DL_ERROR, "%.*s is not a valid universal character",
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(int) (str - base), base);
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result = 1;
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}
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else if (identifier_pos)
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{
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int validity = ucn_valid_in_identifier (pfile, result);
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if (validity == 0)
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cpp_error (pfile, DL_ERROR,
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"universal character %.*s is not valid in an identifier",
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(int) (str - base), base);
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else if (validity == 2 && identifier_pos == 1)
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cpp_error (pfile, DL_ERROR,
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"universal character %.*s is not valid at the start of an identifier",
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(int) (str - base), base);
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}
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/* We don't accept UCNs if iconv is not available or will not
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convert to the target wide character set. */
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else if (!HAVE_ICONV || pfile->wide_cset_desc == (iconv_t) -1)
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{
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/* XXX should be DL_SORRY */
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cpp_error (pfile, DL_ERROR,
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"universal character names are not supported in this configuration");
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}
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if (result == 0)
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result = 1;
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return result;
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}
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/* Convert an UCN, pointed to by FROM, to UTF-8 encoding, then translate
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it to the execution character set and write the result into TBUF.
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An advanced pointer is returned. Issues all relevant diagnostics.
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UTF-8 encoding looks like this:
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value range encoded as
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00000000-0000007F 0xxxxxxx
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00000080-000007FF 110xxxxx 10xxxxxx
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00000800-0000FFFF 1110xxxx 10xxxxxx 10xxxxxx
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00010000-001FFFFF 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
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00200000-03FFFFFF 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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04000000-7FFFFFFF 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
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Values in the 0000D800 ... 0000DFFF range (surrogates) are invalid,
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which means that three-byte sequences ED xx yy, with A0 <= xx <= BF,
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never occur. Note also that any value that can be encoded by a
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given row of the table can also be encoded by all successive rows,
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but this is not done; only the shortest possible encoding for any
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given value is valid. For instance, the character 07C0 could be
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encoded as any of DF 80, E0 9F 80, F0 80 9F 80, F8 80 80 9F 80, or
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FC 80 80 80 9F 80. Only the first is valid. */
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static const uchar *
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convert_ucn (cpp_reader *pfile, const uchar *from, const uchar *limit,
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struct strbuf *tbuf, bool wide)
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{
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int nbytes;
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uchar buf[6], *p = &buf[6];
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static const uchar masks[6] = { 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
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cppchar_t ucn;
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from++; /* skip u/U */
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ucn = _cpp_valid_ucn (pfile, &from, limit, 0);
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if (!ucn)
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return from;
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nbytes = 1;
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if (ucn < 0x80)
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*--p = ucn;
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else
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{
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do
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{
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*--p = ((ucn & 0x3F) | 0x80);
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ucn >>= 6;
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nbytes++;
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}
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while (ucn >= 0x3F || (ucn & masks[nbytes-1]));
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*--p = (ucn | masks[nbytes-1]);
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}
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if (!convert_cset (wide ? pfile->wide_cset_desc : pfile->narrow_cset_desc,
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p, nbytes, tbuf))
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cpp_errno (pfile, DL_ERROR, "converting UCN to execution character set");
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return from;
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}
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static void
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emit_numeric_escape (cpp_reader *pfile, cppchar_t n,
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struct strbuf *tbuf, bool wide)
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{
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if (wide)
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{
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/* We have to render this into the target byte order, which may not
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be our byte order. */
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bool bigend = CPP_OPTION (pfile, bytes_big_endian);
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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 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, 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, DL_ERROR,
|
||
"\\x used with no following hex digits");
|
||
return from;
|
||
}
|
||
|
||
if (overflow | (n != (n & mask)))
|
||
{
|
||
cpp_error (pfile, 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 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, 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 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;
|
||
|
||
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, 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, DL_PEDWARN,
|
||
"non-ISO-standard escape sequence, '\\%c'", (int) c);
|
||
c = charconsts[2];
|
||
break;
|
||
|
||
default:
|
||
unknown:
|
||
if (ISGRAPH (c))
|
||
cpp_error (pfile, DL_PEDWARN,
|
||
"unknown escape sequence '\\%c'", (int) c);
|
||
else
|
||
cpp_error (pfile, DL_PEDWARN,
|
||
"unknown escape sequence: '\\%03o'", (int) c);
|
||
}
|
||
|
||
/* Now convert what we have to the execution character set. */
|
||
if (!convert_cset (wide ? pfile->wide_cset_desc : pfile->narrow_cset_desc,
|
||
&c, 1, tbuf))
|
||
cpp_errno (pfile, 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 strbuf tbuf;
|
||
const uchar *p, *base, *limit;
|
||
size_t i;
|
||
iconv_t cd = 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 (!convert_cset (cd, 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, DL_ERROR, "converting to execution character set");
|
||
free (tbuf.text);
|
||
return false;
|
||
}
|
||
|
||
/* 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, DL_WARNING, "character constant too long for its type");
|
||
}
|
||
else if (i > 1 && CPP_OPTION (pfile, warn_multichar))
|
||
cpp_error (pfile, 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, 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, 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;
|
||
}
|