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/*
*
* Copyright (c) 2004
* John Maddock
*
* Use, modification and distribution are subject to 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)
*
*/
/*
* LOCATION: see http://www.boost.org for most recent version.
* FILE basic_regex_creator.cpp
* VERSION see <boost/version.hpp>
* DESCRIPTION: Declares template class basic_regex_creator which fills in
* the data members of a regex_data object.
*/
#ifndef BOOST_REGEX_V4_BASIC_REGEX_CREATOR_HPP
#define BOOST_REGEX_V4_BASIC_REGEX_CREATOR_HPP
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_PREFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
#ifdef BOOST_MSVC
# pragma warning(push)
# pragma warning(disable: 4800)
#endif
namespace boost{
namespace re_detail{
template <class charT>
struct digraph : public std::pair<charT, charT>
{
digraph() : std::pair<charT, charT>(0, 0){}
digraph(charT c1) : std::pair<charT, charT>(c1, 0){}
digraph(charT c1, charT c2) : std::pair<charT, charT>(c1, c2)
{}
#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
digraph(const digraph<charT>& d) : std::pair<charT, charT>(d.first, d.second){}
#endif
template <class Seq>
digraph(const Seq& s) : std::pair<charT, charT>()
{
BOOST_ASSERT(s.size() <= 2);
BOOST_ASSERT(s.size());
this->first = s[0];
this->second = (s.size() > 1) ? s[1] : 0;
}
};
template <class charT, class traits>
class basic_char_set
{
public:
typedef digraph<charT> digraph_type;
typedef typename traits::string_type string_type;
typedef typename traits::char_class_type mask_type;
basic_char_set()
{
m_negate = false;
m_has_digraphs = false;
m_classes = 0;
m_negated_classes = 0;
m_empty = true;
}
void add_single(const digraph_type& s)
{
m_singles.insert(m_singles.end(), s);
if(s.second)
m_has_digraphs = true;
m_empty = false;
}
void add_range(const digraph_type& first, const digraph_type& end)
{
m_ranges.insert(m_ranges.end(), first);
m_ranges.insert(m_ranges.end(), end);
if(first.second)
{
m_has_digraphs = true;
add_single(first);
}
if(end.second)
{
m_has_digraphs = true;
add_single(end);
}
m_empty = false;
}
void add_class(mask_type m)
{
m_classes |= m;
m_empty = false;
}
void add_negated_class(mask_type m)
{
m_negated_classes |= m;
m_empty = false;
}
void add_equivalent(const digraph_type& s)
{
m_equivalents.insert(m_equivalents.end(), s);
if(s.second)
{
m_has_digraphs = true;
add_single(s);
}
m_empty = false;
}
void negate()
{
m_negate = true;
//m_empty = false;
}
//
// accessor functions:
//
bool has_digraphs()const
{
return m_has_digraphs;
}
bool is_negated()const
{
return m_negate;
}
typedef typename std::vector<digraph_type>::const_iterator list_iterator;
list_iterator singles_begin()const
{
return m_singles.begin();
}
list_iterator singles_end()const
{
return m_singles.end();
}
list_iterator ranges_begin()const
{
return m_ranges.begin();
}
list_iterator ranges_end()const
{
return m_ranges.end();
}
list_iterator equivalents_begin()const
{
return m_equivalents.begin();
}
list_iterator equivalents_end()const
{
return m_equivalents.end();
}
mask_type classes()const
{
return m_classes;
}
mask_type negated_classes()const
{
return m_negated_classes;
}
bool empty()const
{
return m_empty;
}
private:
std::vector<digraph_type> m_singles; // a list of single characters to match
std::vector<digraph_type> m_ranges; // a list of end points of our ranges
bool m_negate; // true if the set is to be negated
bool m_has_digraphs; // true if we have digraphs present
mask_type m_classes; // character classes to match
mask_type m_negated_classes; // negated character classes to match
bool m_empty; // whether we've added anything yet
std::vector<digraph_type> m_equivalents; // a list of equivalence classes
};
template <class charT, class traits>
class basic_regex_creator
{
public:
basic_regex_creator(regex_data<charT, traits>* data);
std::ptrdiff_t getoffset(void* addr)
{
return getoffset(addr, m_pdata->m_data.data());
}
std::ptrdiff_t getoffset(const void* addr, const void* base)
{
return static_cast<const char*>(addr) - static_cast<const char*>(base);
}
re_syntax_base* getaddress(std::ptrdiff_t off)
{
return getaddress(off, m_pdata->m_data.data());
}
re_syntax_base* getaddress(std::ptrdiff_t off, void* base)
{
return static_cast<re_syntax_base*>(static_cast<void*>(static_cast<char*>(base) + off));
}
void init(unsigned l_flags)
{
m_pdata->m_flags = l_flags;
m_icase = l_flags & regex_constants::icase;
}
regbase::flag_type flags()
{
return m_pdata->m_flags;
}
void flags(regbase::flag_type f)
{
m_pdata->m_flags = f;
if(m_icase != static_cast<bool>(f & regbase::icase))
{
m_icase = static_cast<bool>(f & regbase::icase);
}
}
re_syntax_base* append_state(syntax_element_type t, std::size_t s = sizeof(re_syntax_base));
re_syntax_base* insert_state(std::ptrdiff_t pos, syntax_element_type t, std::size_t s = sizeof(re_syntax_base));
re_literal* append_literal(charT c);
re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set);
re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set, mpl::false_*);
re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set, mpl::true_*);
void finalize(const charT* p1, const charT* p2);
protected:
regex_data<charT, traits>* m_pdata; // pointer to the basic_regex_data struct we are filling in
const ::boost::regex_traits_wrapper<traits>&
m_traits; // convenience reference to traits class
re_syntax_base* m_last_state; // the last state we added
bool m_icase; // true for case insensitive matches
unsigned m_repeater_id; // the state_id of the next repeater
bool m_has_backrefs; // true if there are actually any backrefs
unsigned m_backrefs; // bitmask of permitted backrefs
boost::uintmax_t m_bad_repeats; // bitmask of repeats we can't deduce a startmap for;
bool m_has_recursions; // set when we have recursive expresisons to fixup
typename traits::char_class_type m_word_mask; // mask used to determine if a character is a word character
typename traits::char_class_type m_mask_space; // mask used to determine if a character is a word character
typename traits::char_class_type m_lower_mask; // mask used to determine if a character is a lowercase character
typename traits::char_class_type m_upper_mask; // mask used to determine if a character is an uppercase character
typename traits::char_class_type m_alpha_mask; // mask used to determine if a character is an alphabetic character
private:
basic_regex_creator& operator=(const basic_regex_creator&);
basic_regex_creator(const basic_regex_creator&);
void fixup_pointers(re_syntax_base* state);
void fixup_recursions(re_syntax_base* state);
void create_startmaps(re_syntax_base* state);
int calculate_backstep(re_syntax_base* state);
void create_startmap(re_syntax_base* state, unsigned char* l_map, unsigned int* pnull, unsigned char mask);
unsigned get_restart_type(re_syntax_base* state);
void set_all_masks(unsigned char* bits, unsigned char);
bool is_bad_repeat(re_syntax_base* pt);
void set_bad_repeat(re_syntax_base* pt);
syntax_element_type get_repeat_type(re_syntax_base* state);
void probe_leading_repeat(re_syntax_base* state);
};
template <class charT, class traits>
basic_regex_creator<charT, traits>::basic_regex_creator(regex_data<charT, traits>* data)
: m_pdata(data), m_traits(*(data->m_ptraits)), m_last_state(0), m_repeater_id(0), m_has_backrefs(false), m_backrefs(0), m_has_recursions(false)
{
m_pdata->m_data.clear();
m_pdata->m_status = ::boost::regex_constants::error_ok;
static const charT w = 'w';
static const charT s = 's';
static const charT l[5] = { 'l', 'o', 'w', 'e', 'r', };
static const charT u[5] = { 'u', 'p', 'p', 'e', 'r', };
static const charT a[5] = { 'a', 'l', 'p', 'h', 'a', };
m_word_mask = m_traits.lookup_classname(&w, &w +1);
m_mask_space = m_traits.lookup_classname(&s, &s +1);
m_lower_mask = m_traits.lookup_classname(l, l + 5);
m_upper_mask = m_traits.lookup_classname(u, u + 5);
m_alpha_mask = m_traits.lookup_classname(a, a + 5);
m_pdata->m_word_mask = m_word_mask;
BOOST_ASSERT(m_word_mask != 0);
BOOST_ASSERT(m_mask_space != 0);
BOOST_ASSERT(m_lower_mask != 0);
BOOST_ASSERT(m_upper_mask != 0);
BOOST_ASSERT(m_alpha_mask != 0);
}
template <class charT, class traits>
re_syntax_base* basic_regex_creator<charT, traits>::append_state(syntax_element_type t, std::size_t s)
{
// if the state is a backref then make a note of it:
if(t == syntax_element_backref)
this->m_has_backrefs = true;
// append a new state, start by aligning our last one:
m_pdata->m_data.align();
// set the offset to the next state in our last one:
if(m_last_state)
m_last_state->next.i = m_pdata->m_data.size() - getoffset(m_last_state);
// now actually extent our data:
m_last_state = static_cast<re_syntax_base*>(m_pdata->m_data.extend(s));
// fill in boilerplate options in the new state:
m_last_state->next.i = 0;
m_last_state->type = t;
return m_last_state;
}
template <class charT, class traits>
re_syntax_base* basic_regex_creator<charT, traits>::insert_state(std::ptrdiff_t pos, syntax_element_type t, std::size_t s)
{
// append a new state, start by aligning our last one:
m_pdata->m_data.align();
// set the offset to the next state in our last one:
if(m_last_state)
m_last_state->next.i = m_pdata->m_data.size() - getoffset(m_last_state);
// remember the last state position:
std::ptrdiff_t off = getoffset(m_last_state) + s;
// now actually insert our data:
re_syntax_base* new_state = static_cast<re_syntax_base*>(m_pdata->m_data.insert(pos, s));
// fill in boilerplate options in the new state:
new_state->next.i = s;
new_state->type = t;
m_last_state = getaddress(off);
return new_state;
}
template <class charT, class traits>
re_literal* basic_regex_creator<charT, traits>::append_literal(charT c)
{
re_literal* result;
// start by seeing if we have an existing re_literal we can extend:
if((0 == m_last_state) || (m_last_state->type != syntax_element_literal))
{
// no existing re_literal, create a new one:
result = static_cast<re_literal*>(append_state(syntax_element_literal, sizeof(re_literal) + sizeof(charT)));
result->length = 1;
*static_cast<charT*>(static_cast<void*>(result+1)) = m_traits.translate(c, m_icase);
}
else
{
// we have an existing re_literal, extend it:
std::ptrdiff_t off = getoffset(m_last_state);
m_pdata->m_data.extend(sizeof(charT));
m_last_state = result = static_cast<re_literal*>(getaddress(off));
charT* characters = static_cast<charT*>(static_cast<void*>(result+1));
characters[result->length] = m_traits.translate(c, m_icase);
++(result->length);
}
return result;
}
template <class charT, class traits>
inline re_syntax_base* basic_regex_creator<charT, traits>::append_set(
const basic_char_set<charT, traits>& char_set)
{
typedef mpl::bool_< (sizeof(charT) == 1) > truth_type;
return char_set.has_digraphs()
? append_set(char_set, static_cast<mpl::false_*>(0))
: append_set(char_set, static_cast<truth_type*>(0));
}
template <class charT, class traits>
re_syntax_base* basic_regex_creator<charT, traits>::append_set(
const basic_char_set<charT, traits>& char_set, mpl::false_*)
{
typedef typename traits::string_type string_type;
typedef typename basic_char_set<charT, traits>::list_iterator item_iterator;
typedef typename traits::char_class_type mask_type;
re_set_long<mask_type>* result = static_cast<re_set_long<mask_type>*>(append_state(syntax_element_long_set, sizeof(re_set_long<mask_type>)));
//
// fill in the basics:
//
result->csingles = static_cast<unsigned int>(::boost::re_detail::distance(char_set.singles_begin(), char_set.singles_end()));
result->cranges = static_cast<unsigned int>(::boost::re_detail::distance(char_set.ranges_begin(), char_set.ranges_end())) / 2;
result->cequivalents = static_cast<unsigned int>(::boost::re_detail::distance(char_set.equivalents_begin(), char_set.equivalents_end()));
result->cclasses = char_set.classes();
result->cnclasses = char_set.negated_classes();
if(flags() & regbase::icase)
{
// adjust classes as needed:
if(((result->cclasses & m_lower_mask) == m_lower_mask) || ((result->cclasses & m_upper_mask) == m_upper_mask))
result->cclasses |= m_alpha_mask;
if(((result->cnclasses & m_lower_mask) == m_lower_mask) || ((result->cnclasses & m_upper_mask) == m_upper_mask))
result->cnclasses |= m_alpha_mask;
}
result->isnot = char_set.is_negated();
result->singleton = !char_set.has_digraphs();
//
// remember where the state is for later:
//
std::ptrdiff_t offset = getoffset(result);
//
// now extend with all the singles:
//
item_iterator first, last;
first = char_set.singles_begin();
last = char_set.singles_end();
while(first != last)
{
charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (first->second ? 3 : 2)));
p[0] = m_traits.translate(first->first, m_icase);
if(first->second)
{
p[1] = m_traits.translate(first->second, m_icase);
p[2] = 0;
}
else
p[1] = 0;
++first;
}
//
// now extend with all the ranges:
//
first = char_set.ranges_begin();
last = char_set.ranges_end();
while(first != last)
{
// first grab the endpoints of the range:
digraph<charT> c1 = *first;
c1.first = this->m_traits.translate(c1.first, this->m_icase);
c1.second = this->m_traits.translate(c1.second, this->m_icase);
++first;
digraph<charT> c2 = *first;
c2.first = this->m_traits.translate(c2.first, this->m_icase);
c2.second = this->m_traits.translate(c2.second, this->m_icase);
++first;
string_type s1, s2;
// different actions now depending upon whether collation is turned on:
if(flags() & regex_constants::collate)
{
// we need to transform our range into sort keys:
#if BOOST_WORKAROUND(__GNUC__, < 3)
string_type in(3, charT(0));
in[0] = c1.first;
in[1] = c1.second;
s1 = this->m_traits.transform(in.c_str(), (in[1] ? in.c_str()+2 : in.c_str()+1));
in[0] = c2.first;
in[1] = c2.second;
s2 = this->m_traits.transform(in.c_str(), (in[1] ? in.c_str()+2 : in.c_str()+1));
#else
charT a1[3] = { c1.first, c1.second, charT(0), };
charT a2[3] = { c2.first, c2.second, charT(0), };
s1 = this->m_traits.transform(a1, (a1[1] ? a1+2 : a1+1));
s2 = this->m_traits.transform(a2, (a2[1] ? a2+2 : a2+1));
#endif
if(s1.size() == 0)
s1 = string_type(1, charT(0));
if(s2.size() == 0)
s2 = string_type(1, charT(0));
}
else
{
if(c1.second)
{
s1.insert(s1.end(), c1.first);
s1.insert(s1.end(), c1.second);
}
else
s1 = string_type(1, c1.first);
if(c2.second)
{
s2.insert(s2.end(), c2.first);
s2.insert(s2.end(), c2.second);
}
else
s2.insert(s2.end(), c2.first);
}
if(s1 > s2)
{
// Oops error:
return 0;
}
charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (s1.size() + s2.size() + 2) ) );
re_detail::copy(s1.begin(), s1.end(), p);
p[s1.size()] = charT(0);
p += s1.size() + 1;
re_detail::copy(s2.begin(), s2.end(), p);
p[s2.size()] = charT(0);
}
//
// now process the equivalence classes:
//
first = char_set.equivalents_begin();
last = char_set.equivalents_end();
while(first != last)
{
string_type s;
if(first->second)
{
#if BOOST_WORKAROUND(__GNUC__, < 3)
string_type in(3, charT(0));
in[0] = first->first;
in[1] = first->second;
s = m_traits.transform_primary(in.c_str(), in.c_str()+2);
#else
charT cs[3] = { first->first, first->second, charT(0), };
s = m_traits.transform_primary(cs, cs+2);
#endif
}
else
s = m_traits.transform_primary(&first->first, &first->first+1);
if(s.empty())
return 0; // invalid or unsupported equivalence class
charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (s.size()+1) ) );
re_detail::copy(s.begin(), s.end(), p);
p[s.size()] = charT(0);
++first;
}
//
// finally reset the address of our last state:
//
m_last_state = result = static_cast<re_set_long<mask_type>*>(getaddress(offset));
return result;
}
namespace{
template<class T>
inline bool char_less(T t1, T t2)
{
return t1 < t2;
}
template<>
inline bool char_less<char>(char t1, char t2)
{
return static_cast<unsigned char>(t1) < static_cast<unsigned char>(t2);
}
template<>
inline bool char_less<signed char>(signed char t1, signed char t2)
{
return static_cast<unsigned char>(t1) < static_cast<unsigned char>(t2);
}
}
template <class charT, class traits>
re_syntax_base* basic_regex_creator<charT, traits>::append_set(
const basic_char_set<charT, traits>& char_set, mpl::true_*)
{
typedef typename traits::string_type string_type;
typedef typename basic_char_set<charT, traits>::list_iterator item_iterator;
re_set* result = static_cast<re_set*>(append_state(syntax_element_set, sizeof(re_set)));
bool negate = char_set.is_negated();
std::memset(result->_map, 0, sizeof(result->_map));
//
// handle singles first:
//
item_iterator first, last;
first = char_set.singles_begin();
last = char_set.singles_end();
while(first != last)
{
for(unsigned int i = 0; i < (1 << CHAR_BIT); ++i)
{
if(this->m_traits.translate(static_cast<charT>(i), this->m_icase)
== this->m_traits.translate(first->first, this->m_icase))
result->_map[i] = true;
}
++first;
}
//
// OK now handle ranges:
//
first = char_set.ranges_begin();
last = char_set.ranges_end();
while(first != last)
{
// first grab the endpoints of the range:
charT c1 = this->m_traits.translate(first->first, this->m_icase);
++first;
charT c2 = this->m_traits.translate(first->first, this->m_icase);
++first;
// different actions now depending upon whether collation is turned on:
if(flags() & regex_constants::collate)
{
// we need to transform our range into sort keys:
charT c3[2] = { c1, charT(0), };
string_type s1 = this->m_traits.transform(c3, c3+1);
c3[0] = c2;
string_type s2 = this->m_traits.transform(c3, c3+1);
if(s1 > s2)
{
// Oops error:
return 0;
}
BOOST_ASSERT(c3[1] == charT(0));
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
{
c3[0] = static_cast<charT>(i);
string_type s3 = this->m_traits.transform(c3, c3 +1);
if((s1 <= s3) && (s3 <= s2))
result->_map[i] = true;
}
}
else
{
if(char_less<charT>(c2, c1))
{
// Oops error:
return 0;
}
// everything in range matches:
std::memset(result->_map + static_cast<unsigned char>(c1), true, 1 + static_cast<unsigned char>(c2) - static_cast<unsigned char>(c1));
}
}
//
// and now the classes:
//
typedef typename traits::char_class_type mask_type;
mask_type m = char_set.classes();
if(flags() & regbase::icase)
{
// adjust m as needed:
if(((m & m_lower_mask) == m_lower_mask) || ((m & m_upper_mask) == m_upper_mask))
m |= m_alpha_mask;
}
if(m != 0)
{
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
{
if(this->m_traits.isctype(static_cast<charT>(i), m))
result->_map[i] = true;
}
}
//
// and now the negated classes:
//
m = char_set.negated_classes();
if(flags() & regbase::icase)
{
// adjust m as needed:
if(((m & m_lower_mask) == m_lower_mask) || ((m & m_upper_mask) == m_upper_mask))
m |= m_alpha_mask;
}
if(m != 0)
{
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
{
if(0 == this->m_traits.isctype(static_cast<charT>(i), m))
result->_map[i] = true;
}
}
//
// now process the equivalence classes:
//
first = char_set.equivalents_begin();
last = char_set.equivalents_end();
while(first != last)
{
string_type s;
BOOST_ASSERT(static_cast<charT>(0) == first->second);
s = m_traits.transform_primary(&first->first, &first->first+1);
if(s.empty())
return 0; // invalid or unsupported equivalence class
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
{
charT c[2] = { (static_cast<charT>(i)), charT(0), };
string_type s2 = this->m_traits.transform_primary(c, c+1);
if(s == s2)
result->_map[i] = true;
}
++first;
}
if(negate)
{
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
{
result->_map[i] = !(result->_map[i]);
}
}
return result;
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::finalize(const charT* p1, const charT* p2)
{
if(this->m_pdata->m_status)
return;
// we've added all the states we need, now finish things off.
// start by adding a terminating state:
append_state(syntax_element_match);
// extend storage to store original expression:
std::ptrdiff_t len = p2 - p1;
m_pdata->m_expression_len = len;
charT* ps = static_cast<charT*>(m_pdata->m_data.extend(sizeof(charT) * (1 + (p2 - p1))));
m_pdata->m_expression = ps;
re_detail::copy(p1, p2, ps);
ps[p2 - p1] = 0;
// fill in our other data...
// successful parsing implies a zero status:
m_pdata->m_status = 0;
// get the first state of the machine:
m_pdata->m_first_state = static_cast<re_syntax_base*>(m_pdata->m_data.data());
// fixup pointers in the machine:
fixup_pointers(m_pdata->m_first_state);
if(m_has_recursions)
{
m_pdata->m_has_recursions = true;
fixup_recursions(m_pdata->m_first_state);
if(this->m_pdata->m_status)
return;
}
else
m_pdata->m_has_recursions = false;
// create nested startmaps:
create_startmaps(m_pdata->m_first_state);
// create main startmap:
std::memset(m_pdata->m_startmap, 0, sizeof(m_pdata->m_startmap));
m_pdata->m_can_be_null = 0;
m_bad_repeats = 0;
create_startmap(m_pdata->m_first_state, m_pdata->m_startmap, &(m_pdata->m_can_be_null), mask_all);
// get the restart type:
m_pdata->m_restart_type = get_restart_type(m_pdata->m_first_state);
// optimise a leading repeat if there is one:
probe_leading_repeat(m_pdata->m_first_state);
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::fixup_pointers(re_syntax_base* state)
{
while(state)
{
switch(state->type)
{
case syntax_element_recurse:
m_has_recursions = true;
if(state->next.i)
state->next.p = getaddress(state->next.i, state);
else
state->next.p = 0;
break;
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
// set the state_id of this repeat:
static_cast<re_repeat*>(state)->state_id = m_repeater_id++;
// fall through:
case syntax_element_alt:
std::memset(static_cast<re_alt*>(state)->_map, 0, sizeof(static_cast<re_alt*>(state)->_map));
static_cast<re_alt*>(state)->can_be_null = 0;
// fall through:
case syntax_element_jump:
static_cast<re_jump*>(state)->alt.p = getaddress(static_cast<re_jump*>(state)->alt.i, state);
// fall through again:
default:
if(state->next.i)
state->next.p = getaddress(state->next.i, state);
else
state->next.p = 0;
}
state = state->next.p;
}
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::fixup_recursions(re_syntax_base* state)
{
re_syntax_base* base = state;
while(state)
{
switch(state->type)
{
case syntax_element_assert_backref:
{
// just check that the index is valid:
int idx = static_cast<const re_brace*>(state)->index;
if(idx < 0)
{
idx = -idx-1;
if(idx >= 10000)
{
idx = m_pdata->get_id(idx);
if(idx <= 0)
{
// check of sub-expression that doesn't exist:
if(0 == this->m_pdata->m_status) // update the error code if not already set
this->m_pdata->m_status = boost::regex_constants::error_bad_pattern;
//
// clear the expression, we should be empty:
//
this->m_pdata->m_expression = 0;
this->m_pdata->m_expression_len = 0;
//
// and throw if required:
//
if(0 == (this->flags() & regex_constants::no_except))
{
std::string message = "Encountered a forward reference to a marked sub-expression that does not exist.";
boost::regex_error e(message, boost::regex_constants::error_bad_pattern, 0);
e.raise();
}
}
}
}
}
break;
case syntax_element_recurse:
{
bool ok = false;
re_syntax_base* p = base;
std::ptrdiff_t idx = static_cast<re_jump*>(state)->alt.i;
if(idx > 10000)
{
//
// There may be more than one capture group with this hash, just do what Perl
// does and recurse to the leftmost:
//
idx = m_pdata->get_id(static_cast<int>(idx));
}
while(p)
{
if((p->type == syntax_element_startmark) && (static_cast<re_brace*>(p)->index == idx))
{
//
// We've found the target of the recursion, set the jump target:
//
static_cast<re_jump*>(state)->alt.p = p;
ok = true;
//
// Now scan the target for nested repeats:
//
p = p->next.p;
int next_rep_id = 0;
while(p)
{
switch(p->type)
{
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
next_rep_id = static_cast<re_repeat*>(p)->state_id;
break;
case syntax_element_endmark:
if(static_cast<const re_brace*>(p)->index == idx)
next_rep_id = -1;
break;
default:
break;
}
if(next_rep_id)
break;
p = p->next.p;
}
if(next_rep_id > 0)
{
static_cast<re_recurse*>(state)->state_id = next_rep_id - 1;
}
break;
}
p = p->next.p;
}
if(!ok)
{
// recursion to sub-expression that doesn't exist:
if(0 == this->m_pdata->m_status) // update the error code if not already set
this->m_pdata->m_status = boost::regex_constants::error_bad_pattern;
//
// clear the expression, we should be empty:
//
this->m_pdata->m_expression = 0;
this->m_pdata->m_expression_len = 0;
//
// and throw if required:
//
if(0 == (this->flags() & regex_constants::no_except))
{
std::string message = "Encountered a forward reference to a recursive sub-expression that does not exist.";
boost::regex_error e(message, boost::regex_constants::error_bad_pattern, 0);
e.raise();
}
}
}
default:
break;
}
state = state->next.p;
}
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::create_startmaps(re_syntax_base* state)
{
// non-recursive implementation:
// create the last map in the machine first, so that earlier maps
// can make use of the result...
//
// This was originally a recursive implementation, but that caused stack
// overflows with complex expressions on small stacks (think COM+).
// start by saving the case setting:
bool l_icase = m_icase;
std::vector<std::pair<bool, re_syntax_base*> > v;
while(state)
{
switch(state->type)
{
case syntax_element_toggle_case:
// we need to track case changes here:
m_icase = static_cast<re_case*>(state)->icase;
state = state->next.p;
continue;
case syntax_element_alt:
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
// just push the state onto our stack for now:
v.push_back(std::pair<bool, re_syntax_base*>(m_icase, state));
state = state->next.p;
break;
case syntax_element_backstep:
// we need to calculate how big the backstep is:
static_cast<re_brace*>(state)->index
= this->calculate_backstep(state->next.p);
if(static_cast<re_brace*>(state)->index < 0)
{
// Oops error:
if(0 == this->m_pdata->m_status) // update the error code if not already set
this->m_pdata->m_status = boost::regex_constants::error_bad_pattern;
//
// clear the expression, we should be empty:
//
this->m_pdata->m_expression = 0;
this->m_pdata->m_expression_len = 0;
//
// and throw if required:
//
if(0 == (this->flags() & regex_constants::no_except))
{
std::string message = "Invalid lookbehind assertion encountered in the regular expression.";
boost::regex_error e(message, boost::regex_constants::error_bad_pattern, 0);
e.raise();
}
}
// fall through:
default:
state = state->next.p;
}
}
// now work through our list, building all the maps as we go:
while(v.size())
{
const std::pair<bool, re_syntax_base*>& p = v.back();
m_icase = p.first;
state = p.second;
v.pop_back();
// Build maps:
m_bad_repeats = 0;
create_startmap(state->next.p, static_cast<re_alt*>(state)->_map, &static_cast<re_alt*>(state)->can_be_null, mask_take);
m_bad_repeats = 0;
create_startmap(static_cast<re_alt*>(state)->alt.p, static_cast<re_alt*>(state)->_map, &static_cast<re_alt*>(state)->can_be_null, mask_skip);
// adjust the type of the state to allow for faster matching:
state->type = this->get_repeat_type(state);
}
// restore case sensitivity:
m_icase = l_icase;
}
template <class charT, class traits>
int basic_regex_creator<charT, traits>::calculate_backstep(re_syntax_base* state)
{
typedef typename traits::char_class_type mask_type;
int result = 0;
while(state)
{
switch(state->type)
{
case syntax_element_startmark:
if((static_cast<re_brace*>(state)->index == -1)
|| (static_cast<re_brace*>(state)->index == -2))
{
state = static_cast<re_jump*>(state->next.p)->alt.p->next.p;
continue;
}
else if(static_cast<re_brace*>(state)->index == -3)
{
state = state->next.p->next.p;
continue;
}
break;
case syntax_element_endmark:
if((static_cast<re_brace*>(state)->index == -1)
|| (static_cast<re_brace*>(state)->index == -2))
return result;
break;
case syntax_element_literal:
result += static_cast<re_literal*>(state)->length;
break;
case syntax_element_wild:
case syntax_element_set:
result += 1;
break;
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_backref:
case syntax_element_rep:
case syntax_element_combining:
case syntax_element_long_set_rep:
case syntax_element_backstep:
{
re_repeat* rep = static_cast<re_repeat *>(state);
// adjust the type of the state to allow for faster matching:
state->type = this->get_repeat_type(state);
if((state->type == syntax_element_dot_rep)
|| (state->type == syntax_element_char_rep)
|| (state->type == syntax_element_short_set_rep))
{
if(rep->max != rep->min)
return -1;
result += static_cast<int>(rep->min);
state = rep->alt.p;
continue;
}
else if((state->type == syntax_element_long_set_rep))
{
BOOST_ASSERT(rep->next.p->type == syntax_element_long_set);
if(static_cast<re_set_long<mask_type>*>(rep->next.p)->singleton == 0)
return -1;
if(rep->max != rep->min)
return -1;
result += static_cast<int>(rep->min);
state = rep->alt.p;
continue;
}
}
return -1;
case syntax_element_long_set:
if(static_cast<re_set_long<mask_type>*>(state)->singleton == 0)
return -1;
result += 1;
break;
case syntax_element_jump:
state = static_cast<re_jump*>(state)->alt.p;
continue;
case syntax_element_alt:
{
int r1 = calculate_backstep(state->next.p);
int r2 = calculate_backstep(static_cast<re_alt*>(state)->alt.p);
if((r1 < 0) || (r1 != r2))
return -1;
return result + r1;
}
default:
break;
}
state = state->next.p;
}
return -1;
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::create_startmap(re_syntax_base* state, unsigned char* l_map, unsigned int* pnull, unsigned char mask)
{
int not_last_jump = 1;
re_syntax_base* recursion_start = 0;
int recursion_sub = 0;
re_syntax_base* recursion_restart = 0;
// track case sensitivity:
bool l_icase = m_icase;
while(state)
{
switch(state->type)
{
case syntax_element_toggle_case:
l_icase = static_cast<re_case*>(state)->icase;
state = state->next.p;
break;
case syntax_element_literal:
{
// don't set anything in *pnull, set each element in l_map
// that could match the first character in the literal:
if(l_map)
{
l_map[0] |= mask_init;
charT first_char = *static_cast<charT*>(static_cast<void*>(static_cast<re_literal*>(state) + 1));
for(unsigned int i = 0; i < (1u << CHAR_BIT); ++i)
{
if(m_traits.translate(static_cast<charT>(i), l_icase) == first_char)
l_map[i] |= mask;
}
}
return;
}
case syntax_element_end_line:
{
// next character must be a line separator (if there is one):
if(l_map)
{
l_map[0] |= mask_init;
l_map['\n'] |= mask;
l_map['\r'] |= mask;
l_map['\f'] |= mask;
l_map[0x85] |= mask;
}
// now figure out if we can match a NULL string at this point:
if(pnull)
create_startmap(state->next.p, 0, pnull, mask);
return;
}
case syntax_element_recurse:
{
if(recursion_start == state)
{
// Infinite recursion!!
if(0 == this->m_pdata->m_status) // update the error code if not already set
this->m_pdata->m_status = boost::regex_constants::error_bad_pattern;
//
// clear the expression, we should be empty:
//
this->m_pdata->m_expression = 0;
this->m_pdata->m_expression_len = 0;
//
// and throw if required:
//
if(0 == (this->flags() & regex_constants::no_except))
{
std::string message = "Encountered an infinite recursion.";
boost::regex_error e(message, boost::regex_constants::error_bad_pattern, 0);
e.raise();
}
}
else if(recursion_start == 0)
{
recursion_start = state;
recursion_restart = state->next.p;
state = static_cast<re_jump*>(state)->alt.p;
if(state->type == syntax_element_startmark)
recursion_sub = static_cast<re_brace*>(state)->index;
else
recursion_sub = 0;
break;
}
// fall through, can't handle nested recursion here...
}
case syntax_element_backref:
// can be null, and any character can match:
if(pnull)
*pnull |= mask;
// fall through:
case syntax_element_wild:
{
// can't be null, any character can match:
set_all_masks(l_map, mask);
return;
}
case syntax_element_match:
{
// must be null, any character can match:
set_all_masks(l_map, mask);
if(pnull)
*pnull |= mask;
return;
}
case syntax_element_word_start:
{
// recurse, then AND with all the word characters:
create_startmap(state->next.p, l_map, pnull, mask);
if(l_map)
{
l_map[0] |= mask_init;
for(unsigned int i = 0; i < (1u << CHAR_BIT); ++i)
{
if(!m_traits.isctype(static_cast<charT>(i), m_word_mask))
l_map[i] &= static_cast<unsigned char>(~mask);
}
}
return;
}
case syntax_element_word_end:
{
// recurse, then AND with all the word characters:
create_startmap(state->next.p, l_map, pnull, mask);
if(l_map)
{
l_map[0] |= mask_init;
for(unsigned int i = 0; i < (1u << CHAR_BIT); ++i)
{
if(m_traits.isctype(static_cast<charT>(i), m_word_mask))
l_map[i] &= static_cast<unsigned char>(~mask);
}
}
return;
}
case syntax_element_buffer_end:
{
// we *must be null* :
if(pnull)
*pnull |= mask;
return;
}
case syntax_element_long_set:
if(l_map)
{
typedef typename traits::char_class_type mask_type;
if(static_cast<re_set_long<mask_type>*>(state)->singleton)
{
l_map[0] |= mask_init;
for(unsigned int i = 0; i < (1u << CHAR_BIT); ++i)
{
charT c = static_cast<charT>(i);
if(&c != re_is_set_member(&c, &c + 1, static_cast<re_set_long<mask_type>*>(state), *m_pdata, m_icase))
l_map[i] |= mask;
}
}
else
set_all_masks(l_map, mask);
}
return;
case syntax_element_set:
if(l_map)
{
l_map[0] |= mask_init;
for(unsigned int i = 0; i < (1u << CHAR_BIT); ++i)
{
if(static_cast<re_set*>(state)->_map[
static_cast<unsigned char>(m_traits.translate(static_cast<charT>(i), l_icase))])
l_map[i] |= mask;
}
}
return;
case syntax_element_jump:
// take the jump:
state = static_cast<re_alt*>(state)->alt.p;
not_last_jump = -1;
break;
case syntax_element_alt:
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
{
re_alt* rep = static_cast<re_alt*>(state);
if(rep->_map[0] & mask_init)
{
if(l_map)
{
// copy previous results:
l_map[0] |= mask_init;
for(unsigned int i = 0; i <= UCHAR_MAX; ++i)
{
if(rep->_map[i] & mask_any)
l_map[i] |= mask;
}
}
if(pnull)
{
if(rep->can_be_null & mask_any)
*pnull |= mask;
}
}
else
{
// we haven't created a startmap for this alternative yet
// so take the union of the two options:
if(is_bad_repeat(state))
{
set_all_masks(l_map, mask);
if(pnull)
*pnull |= mask;
return;
}
set_bad_repeat(state);
create_startmap(state->next.p, l_map, pnull, mask);
if((state->type == syntax_element_alt)
|| (static_cast<re_repeat*>(state)->min == 0)
|| (not_last_jump == 0))
create_startmap(rep->alt.p, l_map, pnull, mask);
}
}
return;
case syntax_element_soft_buffer_end:
// match newline or null:
if(l_map)
{
l_map[0] |= mask_init;
l_map['\n'] |= mask;
l_map['\r'] |= mask;
}
if(pnull)
*pnull |= mask;
return;
case syntax_element_endmark:
// need to handle independent subs as a special case:
if(static_cast<re_brace*>(state)->index < 0)
{
// can be null, any character can match:
set_all_masks(l_map, mask);
if(pnull)
*pnull |= mask;
return;
}
else if(recursion_start && (recursion_sub != 0) && (recursion_sub == static_cast<re_brace*>(state)->index))
{
// recursion termination:
recursion_start = 0;
state = recursion_restart;
break;
}
//
// Normally we just go to the next state... but if this sub-expression is
// the target of a recursion, then we might be ending a recursion, in which
// case we should check whatever follows that recursion, as well as whatever
// follows this state:
//
if(m_pdata->m_has_recursions && static_cast<re_brace*>(state)->index)
{
bool ok = false;
re_syntax_base* p = m_pdata->m_first_state;
while(p)
{
if((p->type == syntax_element_recurse))
{
re_brace* p2 = static_cast<re_brace*>(static_cast<re_jump*>(p)->alt.p);
if((p2->type == syntax_element_startmark) && (p2->index == static_cast<re_brace*>(state)->index))
{
ok = true;
break;
}
}
p = p->next.p;
}
if(ok)
{
create_startmap(p->next.p, l_map, pnull, mask);
}
}
state = state->next.p;
break;
case syntax_element_startmark:
// need to handle independent subs as a special case:
if(static_cast<re_brace*>(state)->index == -3)
{
state = state->next.p->next.p;
break;
}
// otherwise fall through:
default:
state = state->next.p;
}
++not_last_jump;
}
}
template <class charT, class traits>
unsigned basic_regex_creator<charT, traits>::get_restart_type(re_syntax_base* state)
{
//
// find out how the machine starts, so we can optimise the search:
//
while(state)
{
switch(state->type)
{
case syntax_element_startmark:
case syntax_element_endmark:
state = state->next.p;
continue;
case syntax_element_start_line:
return regbase::restart_line;
case syntax_element_word_start:
return regbase::restart_word;
case syntax_element_buffer_start:
return regbase::restart_buf;
case syntax_element_restart_continue:
return regbase::restart_continue;
default:
state = 0;
continue;
}
}
return regbase::restart_any;
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::set_all_masks(unsigned char* bits, unsigned char mask)
{
//
// set mask in all of bits elements,
// if bits[0] has mask_init not set then we can
// optimise this to a call to memset:
//
if(bits)
{
if(bits[0] == 0)
(std::memset)(bits, mask, 1u << CHAR_BIT);
else
{
for(unsigned i = 0; i < (1u << CHAR_BIT); ++i)
bits[i] |= mask;
}
bits[0] |= mask_init;
}
}
template <class charT, class traits>
bool basic_regex_creator<charT, traits>::is_bad_repeat(re_syntax_base* pt)
{
switch(pt->type)
{
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
{
unsigned state_id = static_cast<re_repeat*>(pt)->state_id;
if(state_id > sizeof(m_bad_repeats) * CHAR_BIT)
return true; // run out of bits, assume we can't traverse this one.
static const boost::uintmax_t one = 1uL;
return m_bad_repeats & (one << state_id);
}
default:
return false;
}
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::set_bad_repeat(re_syntax_base* pt)
{
switch(pt->type)
{
case syntax_element_rep:
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
{
unsigned state_id = static_cast<re_repeat*>(pt)->state_id;
static const boost::uintmax_t one = 1uL;
if(state_id <= sizeof(m_bad_repeats) * CHAR_BIT)
m_bad_repeats |= (one << state_id);
}
default:
break;
}
}
template <class charT, class traits>
syntax_element_type basic_regex_creator<charT, traits>::get_repeat_type(re_syntax_base* state)
{
typedef typename traits::char_class_type mask_type;
if(state->type == syntax_element_rep)
{
// check to see if we are repeating a single state:
if(state->next.p->next.p->next.p == static_cast<re_alt*>(state)->alt.p)
{
switch(state->next.p->type)
{
case re_detail::syntax_element_wild:
return re_detail::syntax_element_dot_rep;
case re_detail::syntax_element_literal:
return re_detail::syntax_element_char_rep;
case re_detail::syntax_element_set:
return re_detail::syntax_element_short_set_rep;
case re_detail::syntax_element_long_set:
if(static_cast<re_detail::re_set_long<mask_type>*>(state->next.p)->singleton)
return re_detail::syntax_element_long_set_rep;
break;
default:
break;
}
}
}
return state->type;
}
template <class charT, class traits>
void basic_regex_creator<charT, traits>::probe_leading_repeat(re_syntax_base* state)
{
// enumerate our states, and see if we have a leading repeat
// for which failed search restarts can be optimised;
do
{
switch(state->type)
{
case syntax_element_startmark:
if(static_cast<re_brace*>(state)->index >= 0)
{
state = state->next.p;
continue;
}
if((static_cast<re_brace*>(state)->index == -1)
|| (static_cast<re_brace*>(state)->index == -2))
{
// skip past the zero width assertion:
state = static_cast<const re_jump*>(state->next.p)->alt.p->next.p;
continue;
}
if(static_cast<re_brace*>(state)->index == -3)
{
// Have to skip the leading jump state:
state = state->next.p->next.p;
continue;
}
return;
case syntax_element_endmark:
case syntax_element_start_line:
case syntax_element_end_line:
case syntax_element_word_boundary:
case syntax_element_within_word:
case syntax_element_word_start:
case syntax_element_word_end:
case syntax_element_buffer_start:
case syntax_element_buffer_end:
case syntax_element_restart_continue:
state = state->next.p;
break;
case syntax_element_dot_rep:
case syntax_element_char_rep:
case syntax_element_short_set_rep:
case syntax_element_long_set_rep:
if(this->m_has_backrefs == 0)
static_cast<re_repeat*>(state)->leading = true;
// fall through:
default:
return;
}
}while(state);
}
} // namespace re_detail
} // namespace boost
#ifdef BOOST_MSVC
# pragma warning(pop)
#endif
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_SUFFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
#endif