inline void ReadBSTRFromStream( std::basic_istream< CharT, CharTraitsT > &Istream, ATL::CComBSTR &Str )
{
Str.Empty();
CharT Buff[256];
do
{
Istream.read( Buff, APL_ARRSIZE(Buff) );
ATL::CComBSTR TmpStr(Istream.gcount(), Buff);
Str.Append(TmpStr);
} while(Istream.gcount() == APL_ARRSIZE(Buff));
}
inline void ReadBSTRFromStream( std::basic_istream< WCHAR, CharTraitsT > &Istream, ATL::CComBSTR &Str )
{
//Оптимизация исключающая временные объекты
Str.Empty();
WCHAR Buff[256];
do
{
Istream.read( Buff, APL_ARRSIZE(Buff) );
Str.Append(Buff, Istream.gcount());
}
while(Istream.gcount() == APL_ARRSIZE(Buff));
}
void read_next()
{
parser_.begin_parse();
while (!eof_ && !parser_.done())
{
if (!(index_ < buffer_length_))
{
if (!is_->eof())
{
is_->read(buffer_.data(), buffer_capacity_);
buffer_length_ = static_cast<size_t>(is_->gcount());
if (buffer_length_ == 0)
{
eof_ = true;
}
index_ = 0;
}
else
{
eof_ = true;
}
}
if (!eof_)
{
parser_.parse(buffer_.data(),index_,buffer_length_);
index_ = parser_.index();
}
}
parser_.end_parse();
}
void check_done()
{
while (!eof_)
{
if (!(index_ < buffer_length_))
{
if (!is_->eof())
{
is_->read(buffer_.data(), buffer_capacity_);
buffer_length_ = static_cast<size_t>(is_->gcount());
if (buffer_length_ == 0)
{
eof_ = true;
}
index_ = 0;
}
else
{
eof_ = true;
}
}
if (!eof_)
{
parser_.check_done(buffer_.data(),index_,buffer_length_);
index_ = parser_.index();
}
}
}
std::streamsize ignore_line (
std::basic_istream<CharT>& in, bool always_discard = false )
{
std::streamsize nread = 0;
if ( always_discard
|| ( in.rdbuf()->sungetc() != std::char_traits<CharT>::eof()
&& in.get() != in.widen ( '\n' ) ) )
{
// The stream is good, and we haven't
// read a full line yet, so clear it out
in.ignore ( std::numeric_limits<std::streamsize>::max(), in.widen ( '\n' ) );
nread = in.gcount();
}
return nread;
}
int Buffer::pushBytesFromStream(std::basic_istream<char>& istr, int cnt)
{
if (writeAvailable() < cnt)
cnt = writeAvailable();
istr.read((char*)_tail, cnt);
if (istr.eof())
{
cnt = istr.gcount();
}
else if (istr.fail())
{
return -1;
}
_tail += cnt;
return cnt;
}
void parse(std::basic_istream<CharT> &src, HandlerT &handler)
{
enum Action {
Stay,
Skip
};
const int eos = -1;
typedef std::function<Action (int)> parser_t;
parser_t rule, top, in_string, in_atom, in_comment,
append_escaped, append_escaped_hex;
stack<parser_t> ctx;
unsigned level = 0;
std::string data;
int hex_byte;
auto rule_use = [&](parser_t const &p) {
data = "";
data.reserve(256);
rule = p;
};
auto rule_pop = [&]() {
auto p = ctx.top();
ctx.pop();
rule = p;
};
auto rule_push = [&](parser_t const &after,
parser_t const ¤t) {
ctx.push(after);
rule = current;
};
top = [&](int c) -> Action {
if (c == ')') {
if (!level)
throw Error(src, "Unexpected ')'");
--level;
handler.on_list_end();
} else if (c == '(') {
++level;
handler.on_list_begin();
} else if (c == ';') {
rule_use(in_comment);
} else if (::isspace(c)) {
// do nothing
} else if (c == '"') {
rule_use(in_string);
} else if (c != eos) {
rule_use(in_atom);
return Stay;
}
return Skip;
};
in_comment = [&](int c) -> Action {
if (c != '\n' && c != eos) {
data += c;
} else {
handler.on_comment(std::move(data));
rule_use(top);
}
return Skip;
};
auto in_hex = [&](int c) -> Action {
if (c != eos) {
int n = char2hex(c);
if (n >= 0) {
if (hex_byte < 0) {
hex_byte = (n << 4);
return Skip;
}
hex_byte |= n;
}
}
rule_pop();
return Stay;
};
append_escaped_hex = [&](int) -> Action {
if (hex_byte < 0)
throw Error(src, "Escaped hex is empty");
data += static_cast<char>(hex_byte);
rule_pop();
return Stay;
};
auto process_hex = [&](parser_t const &after) -> Action {
hex_byte = -1;
rule_push(after, in_hex);
return Skip;
};
append_escaped = [&](int c) -> Action {
static const std::unordered_map<char, char>
assoc{{'n', '\n'}, {'t', '\t'}, {'r', '\r'}, {'a', '\a'},
{'b', '\b'}, {'v', '\v'}};
if (c == eos)
throw Error(src, "Expected escaped symbol, got EOS");
if (c == 'x')
return process_hex(append_escaped_hex);
auto p = assoc.find(c);
if (p != assoc.end()) {
data += p->second;
} else {
data += c;
}
rule_pop();
return Skip;
};
auto process_escaped = [&]() -> Action {
rule_push(rule, append_escaped);
return Skip;
};
in_atom = [&](int c) -> Action {
static const std::string bound("()");
if (bound.find(c) != std::string::npos || isspace(c) || c == eos) {
handler.on_atom(std::move(data));
rule_use(top);
return Stay;
} else if (c == '\\') {
return process_escaped();
} else {
data += c;
}
return Skip;
};
in_string = [&](int c) -> Action {
if (c == '"') {
handler.on_string(std::move(data));
rule_use(top);
} else if (c == '\\') {
return process_escaped();
} else if (c == eos) {
throw Error(src, "string is not limited, got EOS");
} else {
data += c;
}
return Skip;
};
rule_use(top);
try {
while (true) {
CharT c = src.get();
if (src.gcount() == 0) {
rule(eos);
break;
}
while (rule(c) == Stay) {}
}
} catch (Error const &e) {
throw;
} catch (std::exception const &e) {
throw;
}
handler.on_eof();
}
