boost/wave/cpplexer/re2clex/cpp_re.hpp
/*=============================================================================
Boost.Wave: A Standard compliant C++ preprocessor library
Re2C based C++ lexer
http://www.boost.org/
Copyright (c) 2001-2012 Hartmut Kaiser. Distributed under the Boost
Software License, Version 1.0. (See accompanying file
LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#if !defined(BOOST_CPP_RE_HPP_B76C4F5E_63E9_4B8A_9975_EC32FA6BF027_INCLUDED)
#define BOOST_CPP_RE_HPP_B76C4F5E_63E9_4B8A_9975_EC32FA6BF027_INCLUDED
#include <boost/assert.hpp>
#include <boost/wave/wave_config.hpp>
#include <boost/wave/token_ids.hpp>
#include <boost/wave/cpplexer/cpplexer_exceptions.hpp>
#include <boost/wave/cpplexer/re2clex/aq.hpp>
#include <boost/wave/cpplexer/re2clex/scanner.hpp>
// this must occur after all of the includes and before any code appears
#ifdef BOOST_HAS_ABI_HEADERS
#include BOOST_ABI_PREFIX
#endif
// suppress warnings about dependent classes not being exported from the dll
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable : 4251 4231 4660)
#endif
///////////////////////////////////////////////////////////////////////////////
#define YYCTYPE uchar
#define YYCURSOR cursor
#define YYLIMIT limit
#define YYMARKER marker
#define YYFILL(n) \
{ \
s->ptr = marker; \
cursor = uchar_wrapper(fill(s, cursor), cursor.column); \
limit = uchar_wrapper (s->lim); \
marker = uchar_wrapper(s->ptr); \
} \
/**/
#include <iosfwd>
///////////////////////////////////////////////////////////////////////////////
#define BOOST_WAVE_UPDATE_CURSOR() \
{ \
s->line += count_backslash_newlines(s, cursor); \
s->curr_column = cursor.column; \
s->cur = cursor; \
s->lim = limit; \
s->ptr = marker; \
} \
/**/
///////////////////////////////////////////////////////////////////////////////
#define BOOST_WAVE_RET(i) \
{ \
BOOST_WAVE_UPDATE_CURSOR() \
if (s->cur > s->lim) \
return T_EOF; /* may happen for empty files */ \
return (i); \
} \
/**/
///////////////////////////////////////////////////////////////////////////////
namespace boost {
namespace wave {
namespace cpplexer {
namespace re2clex {
template<typename Iterator>
struct Scanner;
///////////////////////////////////////////////////////////////////////////////
// The scanner function to call whenever a new token is requested
template<typename Iterator>
BOOST_WAVE_DECL boost::wave::token_id scan(Scanner<Iterator> *s);
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
// Utility functions
#define RE2C_ASSERT BOOST_ASSERT
template<typename Iterator>
int get_one_char(Scanner<Iterator> *s)
{
RE2C_ASSERT(s->first <= s->act && s->act <= s->last);
if (s->act < s->last)
return *(s->act)++;
return -1;
}
template<typename Iterator>
std::ptrdiff_t rewind_stream (Scanner<Iterator> *s, int cnt)
{
std::advance(s->act, cnt);
RE2C_ASSERT(s->first <= s->act && s->act <= s->last);
return std::distance(s->first, s->act);
}
template<typename Iterator>
std::size_t get_first_eol_offset(Scanner<Iterator>* s)
{
if (!AQ_EMPTY(s->eol_offsets))
{
return s->eol_offsets->queue[s->eol_offsets->head];
}
else
{
return (unsigned int)-1;
}
}
template<typename Iterator>
void adjust_eol_offsets(Scanner<Iterator>* s, std::size_t adjustment)
{
aq_queue q;
std::size_t i;
if (!s->eol_offsets)
s->eol_offsets = aq_create();
q = s->eol_offsets;
if (AQ_EMPTY(q))
return;
i = q->head;
while (i != q->tail)
{
if (adjustment > q->queue[i])
q->queue[i] = 0;
else
q->queue[i] -= adjustment;
++i;
if (i == q->max_size)
i = 0;
}
if (adjustment > q->queue[i])
q->queue[i] = 0;
else
q->queue[i] -= adjustment;
}
template<typename Iterator>
int count_backslash_newlines(Scanner<Iterator> *s, uchar *cursor)
{
std::size_t diff, offset;
int skipped = 0;
/* figure out how many backslash-newlines skipped over unknowingly. */
diff = cursor - s->bot;
offset = get_first_eol_offset(s);
while (offset <= diff && offset != (unsigned int)-1)
{
skipped++;
aq_pop(s->eol_offsets);
offset = get_first_eol_offset(s);
}
return skipped;
}
BOOST_WAVE_DECL bool is_backslash(uchar *p, uchar *end, int &len);
#define BOOST_WAVE_BSIZE 196608
template<typename Iterator>
uchar *fill(Scanner<Iterator> *s, uchar *cursor)
{
using namespace std; // some systems have memcpy etc. in namespace std
if(!s->eof)
{
uchar* p;
std::ptrdiff_t cnt = s->tok - s->bot;
if(cnt)
{
if (NULL == s->lim)
s->lim = s->top;
size_t length = s->lim - s->tok;
if(length > 0){
memmove(s->bot, s->tok, length);
}
s->tok = s->cur = s->bot;
s->ptr -= cnt;
cursor -= cnt;
s->lim -= cnt;
adjust_eol_offsets(s, cnt);
}
if((s->top - s->lim) < BOOST_WAVE_BSIZE)
{
uchar *buf = (uchar*) malloc(((s->lim - s->bot) + BOOST_WAVE_BSIZE)*sizeof(uchar));
if (buf == 0)
{
(*s->error_proc)(s, lexing_exception::unexpected_error,
"Out of memory!");
/* get the scanner to stop */
*cursor = 0;
return cursor;
}
size_t length = s->lim - s->tok;
if(length > 0){
memmove(buf, s->tok, length);
}
s->tok = s->cur = buf;
s->ptr = &buf[s->ptr - s->bot];
cursor = &buf[cursor - s->bot];
s->lim = &buf[s->lim - s->bot];
s->top = &s->lim[BOOST_WAVE_BSIZE];
free(s->bot);
s->bot = buf;
}
cnt = std::distance(s->act, s->last);
if (cnt > BOOST_WAVE_BSIZE)
cnt = BOOST_WAVE_BSIZE;
uchar * dst = s->lim;
for (std::ptrdiff_t idx = 0; idx < cnt; ++idx)
{
*dst++ = *s->act++;
}
if (cnt != BOOST_WAVE_BSIZE)
{
s->eof = &s->lim[cnt]; *(s->eof)++ = '\0';
}
/* backslash-newline erasing time */
/* first scan for backslash-newline and erase them */
/* a backslash-newline combination can be 2 (regular) or 4 (trigraph backslash) chars */
/* start checking 3 chars within the old buffer, if possible */
for (p = (std::max)(s->lim - 3, s->cur); p < s->lim + cnt - 2; ++p)
{
int len = 0;
/* is there a backslash, and room afterwards for a newline? */
if (is_backslash(p, s->lim + cnt, len) && ((p + len) < (s->lim + cnt)))
{
if (*(p+len) == '\n')
{
int offset = len + 1;
memmove(p, p + offset, s->lim + cnt - p - offset);
cnt -= offset;
--p;
aq_enqueue(s->eol_offsets, p - s->bot + 1);
}
else if (*(p+len) == '\r')
{
/* is there also room for a newline, and is one present? */
if (((p + len + 1) < s->lim + cnt) && (*(p+len+1) == '\n'))
{
int offset = len + 2;
memmove(p, p + offset, s->lim + cnt - p - offset);
cnt -= offset;
--p;
}
else
{
int offset = len + 1;
memmove(p, p + offset, s->lim + cnt - p - offset);
cnt -= offset;
--p;
}
aq_enqueue(s->eol_offsets, p - s->bot + 1);
}
}
}
/* FIXME: the following code should be fixed to recognize correctly the
trigraph backslash token */
/* check to see if what we just read ends in a backslash */
if (cnt >= 2)
{
uchar last = s->lim[cnt-1];
uchar last2 = s->lim[cnt-2];
/* check \ EOB */
if (last == '\\')
{
int next = get_one_char(s);
/* check for \ \n or \ \r or \ \r \n straddling the border */
if (next == '\n')
{
--cnt; /* chop the final \, we've already read the \n. */
aq_enqueue(s->eol_offsets, cnt + (s->lim - s->bot));
}
else if (next == '\r')
{
int next2 = get_one_char(s);
if (next2 == '\n')
{
--cnt; /* skip the backslash */
}
else
{
/* rewind one, and skip one char */
rewind_stream(s, -1);
--cnt;
}
aq_enqueue(s->eol_offsets, cnt + (s->lim - s->bot));
}
else if (next != -1) /* -1 means end of file */
{
/* next was something else, so rewind the stream */
rewind_stream(s, -1);
}
}
/* check \ \r EOB */
else if (last == '\r' && last2 == '\\')
{
int next = get_one_char(s);
if (next == '\n')
{
cnt -= 2; /* skip the \ \r */
}
else
{
/* rewind one, and skip two chars */
rewind_stream(s, -1);
cnt -= 2;
}
aq_enqueue(s->eol_offsets, cnt + (s->lim - s->bot));
}
/* check \ \n EOB */
else if (last == '\n' && last2 == '\\')
{
cnt -= 2;
aq_enqueue(s->eol_offsets, cnt + (s->lim - s->bot));
}
}
s->lim += cnt;
if (s->eof) /* eof needs adjusting if we erased backslash-newlines */
{
s->eof = s->lim;
*(s->eof)++ = '\0';
}
}
return cursor;
}
///////////////////////////////////////////////////////////////////////////////
// Special wrapper class holding the current cursor position
struct BOOST_WAVE_DECL uchar_wrapper
{
uchar_wrapper (uchar *base_cursor, std::size_t column = 1);
uchar_wrapper& operator++();
uchar_wrapper& operator--();
uchar operator* () const;
operator uchar *() const;
friend BOOST_WAVE_DECL std::ptrdiff_t
operator- (uchar_wrapper const& lhs, uchar_wrapper const& rhs);
uchar *base_cursor;
std::size_t column;
};
///////////////////////////////////////////////////////////////////////////////
template<typename Iterator>
boost::wave::token_id scan(Scanner<Iterator> *s)
{
BOOST_ASSERT(0 != s->error_proc); // error handler must be given
uchar_wrapper cursor (s->tok = s->cur, s->column = s->curr_column);
uchar_wrapper marker (s->ptr);
uchar_wrapper limit (s->lim);
typedef BOOST_WAVE_STRINGTYPE string_type;
string_type rawstringdelim; // for use with C++11 raw string literals
// include the correct Re2C token definition rules
#if (defined (__FreeBSD__) || defined (__DragonFly__) || defined (__OpenBSD__)) && defined (T_DIVIDE)
#undef T_DIVIDE
#endif
#if BOOST_WAVE_USE_STRICT_LEXER != 0
#include "strict_cpp_re.inc"
#else
#include "cpp_re.inc"
#endif
} /* end of scan */
///////////////////////////////////////////////////////////////////////////////
} // namespace re2clex
} // namespace cpplexer
} // namespace wave
} // namespace boost
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
#undef BOOST_WAVE_RET
#undef YYCTYPE
#undef YYCURSOR
#undef YYLIMIT
#undef YYMARKER
#undef YYFILL
// the suffix header occurs after all of the code
#ifdef BOOST_HAS_ABI_HEADERS
#include BOOST_ABI_SUFFIX
#endif
#endif // !defined(BOOST_CPP_RE_HPP_B76C4F5E_63E9_4B8A_9975_EC32FA6BF027_INCLUDED)
