c++ - Boost property_tree错误:在.ini文件中获取元素时，数据转换为 “j”类型失败

Question

我有一个.ini文件，其中包含以下数据

[SYSTEM]
num_of_vps = 1

而且我有这段代码可以读取.ini文件中的元素。 ( uint定义为 typedef unsigned int uint)

boost::property_tree::ptree pt; 
boost::property_tree::ini_parser::read_ini(iniFilePath, pt);
hwCount = pt.get<uint>("SYSTEM.num_of_vps"); 

我从包含以上代码的文件创建了一个文件，并在 main.cc文件的包装函数中将其调用。然后我得到以下错误

terminate called after throwing an instance of 'boost_1_68_0::exception_detail::clone_impl<boost_1_68_0::exception_detail::error_info_injector<boost_1_68_0::property_tree::ptree_bad_data> >'what(): conversion of data to type "j" failedstack trace

#12 0x00002aaab613fcd5 in abort () from /lib64/libc.so.6
#13 0x00002aaab9b29315 in __gnu_cxx::__verbose_terminate_handler () at ../../../../src/gcc-7.3.0/libstdc++-v3/libsupc++/vterminate.cc:95
#14 0x00002aaab9a9e8f6 in __cxxabiv1::__terminate (handler=<optimized out>) at ../../../../src/gcc-7.3.0/libstdc++-v3/libsupc++/eh_terminate.cc:47
#15 0x00002aaab9a9e941 in std::terminate () at ../../../../src/gcc-7.3.0/libstdc++-v3/libsupc++/eh_terminate.cc:57
#16 0x00002aaab9a9ea74 in __cxxabiv1::__cxa_throw (obj=<optimized out>, tinfo=0x2aaab9e1ff60 <typeinfo for boost_1_68_0::exception_detail::clone_impl<boost_1_68_0::exception_detail::error_info_injector<boost_1_68_0::property_tree::ptree_bad_data> >>, dest=0x2aaab99bef18 <boost_1_68_0::exception_detail::clone_impl<boost_1_68_0::exception_detail::error_info_injector<boost_1_68_0::property_tree::ptree_bad_data> >::~clone_impl()>) at ../../../../src/gcc-7.3.0/libstdc++-v3/libsupc++/eh_throw.cc:93
#17 0x00002aaab99bec82 in boost_1_68_0::throw_exception<boost_1_68_0::exception_detail::error_info_injector<boost_1_68_0::property_tree::ptree_bad_data> > (e=...) at throw_exception.hpp:72
#18 0x00002aaab99be576 in boost_1_68_0::exception_detail::throw_exception_<boost_1_68_0::property_tree::ptree_bad_data> (x=..., current_function=0x2aaab9b45fc0 <boost_1_68_0::enable_if<boost_1_68_0::property_tree::detail::is_translator<boost_1_68_0::property_tree::stream_translator<char, std::char_traits<char>, std::allocator<char>, unsigned int> >, unsigned int>::type boost_1_68_0::property_tree::basic_ptree<std::string, std::string, std::less<std::string> >::get_value<unsigned int, boost_1_68_0::property_tree::stream_translator<char, std::char_traits<char>, std::allocator<char>, unsigned int> >(boost_1_68_0::property_tree::stream_translator<char, std::char_traits<char>, std::allocator<char>, unsigned int>) const::__PRETTY_FUNCTION__> "typename boost_1_68_0::enable_if<boost_1_68_0::property_tree::detail::is_translator<Translator>, Type>::type boost_1_68_0::property_tree::basic_ptree<Key, Data, KeyCompare>::get_value(T"..., file=0x2aaab9b45830 "property_tree/detail/ptree_implementation.hpp", line=675) at throw_exception.hpp:89
#19 0x00002aaab99be01e in boost_1_68_0::property_tree::basic_ptree<std::string, std::string, std::less<std::string> >::get_value<unsigned int, boost_1_68_0::property_tree::stream_translator<char, std::char_traits<char>, std::allocator<char>, unsigned int> > (this=0xbc86c8, tr=...) at property_tree/detail/ptree_implementation.hpp:673
#20 0x00002aaab99bd6a5 in boost_1_68_0::property_tree::basic_ptree<std::string, std::string, std::less<std::string> >::get_value<unsigned int> (this=0xbc86c8) at property_tree/detail/ptree_implementation.hpp:683
#21 0x00002aaab99bc545 in boost_1_68_0::property_tree::basic_ptree<std::string, std::string, std::less<std::string> >::get<unsigned int> (this=0x7fffffff9470, path=...) at property_tree/detail/ptree_implementation.hpp:754
#22 0x00002aaab99bba83 in MyRT::DUTConfigFile::readIniFile (this=0xbc5d50, iniFilePath=...) at DUTConfigFile.cpp:231
#23 0x00002aaab99ba8d2 in MyRT::DUTConfigFile::DUTConfigFile (this=0xbc5d50, iniFilePath=..., configFilePath=...) at DUTConfigFile.cpp:26
#24 0x00002aaab99c0839 in setupMyConfigs () at SimXLInterface.cpp:83
#31 0x0000000000408847 in main ()

我尝试了gdb，当使用istringstream将字符串转换为uint时，它引发了异常。以下是两种过渡类型

template<class K, class D, class C>                                                                                                                    
template<class Type> inline                                                                                                                            
Type basic_ptree<K, D, C>::get_value() const
{
    return get_value<Type>(
        typename translator_between<data_type, Type>::type());
}

(gdb) p typeid(Type).name()
$2 = 0x2aaab5c33c91 <typeinfo name for unsigned int> "j"
(gdb) p typeid(data_type).name()
could not find typeinfo symbol for 'std::basic_string<char, std::char_traits<char>, std::allocator<char> >'

basic_ios.h中的以下函数引发 __throw_bad_cast()异常(此处为 this->_M_num_get = NULL)

const __num_get_type& __ng = __check_facet(this->_M_num_get);

内部构建自动化Makefile默认将 -D_GLIBCXX_USE_CXX11_ABI=0添加到目标文件创建中

g++ -I/usr/myboost/boost/boost -Wall -std=c++14 -fopenmp -m64 -msse2 -fPIC \
  -D_GLIBCXX_USE_CXX11_ABI=0 -g -o *.o -fPIC -c *.cpp

.so建筑命令

g++ -m64 -msse2 -pthread -shared -static-libstdc++ -static-libgcc  \
  -Wl,-znoexecstack -g -o runtime.so *.o -ldl -lrt -lz -fopenmp -lcrypto

如果我将其更改为读取std::string类型，然后将其转换为uint，则它将正常工作

std::string strHwCount = pt.get<std::string>("SYSTEM.num_of_vps");
hwCount = static_cast<uint>(std::stoul(strHwCount));

我正在使用 boost-1.68和 gcc-7.3。这与我使用的 ABI宏有关吗？没有以上解决方法，有没有办法解决这个问题

更新
首先，我将项目从cmake迁移到内部自定义构建自动化(Makefile的某些增强版本)。在cmake中，这很好。根据sehe的回答，我做了一些进一步的分析。
在一个小的独立示例中，此错误无法重现(使用本地字符串和实际的.ini文件读取)。
通过gdb时，在 boost/property_tree/stream_translator.hpp文件中，我可以在 num_of_vps = 4和 string中找到从文件读取的值(已在文件中更改为 istringstream)。

optional<Type> basic_ptree<K, D, C>
    ::get_value_optional(Translator tr) const
{
    return tr.get_value(data());
}

(gdb) p data()
$1 = "4"

boost_1_68_0::optional<E> get_value(const internal_type &v) {
    std::basic_istringstream<Ch, Traits, Alloc> iss(v);
    iss.imbue(m_loc);
    E e;
    customized::extract(iss, e);
    ....
}

(gdb) p v
$1 = "4"
(gdb) p iss.str()
$2 = "4"

在上面的 customized::extract(iss, e)函数内部，有一个使用 string的 unsigned int到 basic_istream转换

static void extract(std::basic_istream<Ch, Traits>& s, E& e) {
    s >> e;
    if(!s.eof()) { s >> std::ws; }
} 

在此 >>运算符内有一个 _M_extract函数，在该 __check_facet函数内引发异常(通过检查 this->_M_num_get的NULL)

basic_istream<_CharT, _Traits>::
_M_extract(_ValueT& __v) {
  __try {
    const __num_get_type& __ng = __check_facet(this->_M_num_get);
    ...

inline const _Facet&
__check_facet(const _Facet* __f) {
  if (!__f)
    __throw_bad_cast();
  return *__f;
}

方案上方的堆栈跟踪

#0  std::istream::_M_extract<unsigned int>(unsigned int&) (__f=0x0) at gcc-7.3.0/objdir/x86_64-centos-linux/libstdc++-v3/include/bits/basic_ios.h:49
#1  std::istream::operator>>(unsigned int&) (this=0x7fffffff9980, __n=@0x7fffffff997c: 0)
#2  boost_1_68_0::property_tree::customize_stream::extract(std::istream&, unsigned int&) (s=..., e=@0x7fffffff997c: 0)
#3  boost_1_68_0::property_tree::stream_translator<char, std::char_traits<char>, std::allocator<char>, unsigned int>::get_value(std::string const&) (this=0x7fffffff9b58, v="4")

在另一个我们使用 std::stringstream 的地方，我可以看到相同的行为。即使 ss运算符添加了字符串，变量 <<仍显示为空

std::stringstream ss;
ss << std::setw(8) << std::setfill('0') << std::hex << firmId;

我担心 ABI标志会导致此问题，但是我能够将其删除，问题仍然存在。我搜索了这种 istream问题，但找不到任何有用的东西。

Answer 1

您的输入已损坏。可能它使用了您没有想到的编码或代码点，但对人类读者并不突出。

Live On Coliru

#include <boost/property_tree/ini_parser.hpp>
#include <iostream>

int main() {
    std::istringstream iss(R"([SYSTEM]
num_of_vps = 1)");
    boost::property_tree::ptree pt;
    read_ini(iss, pt);

    uint hwCount = pt.get<uint>("SYSTEM.num_of_vps"); 

    std::cout << "hwCount: " << hwCount << "\n";
}

版画

hwCount: 1

但是，如果您将输入更改为例如

    std::istringstream iss(R"([SYSTEM]
num_of_vps = 1)");

(请注意 =后面的空格现在是 < > 160, \240, U+00A0 NO-BREAK SPACE, ^KNS, &nbsp;)它将打印:

Live On Coliru

版画

terminate called after throwing an instance of 'boost::wrapexcept<boost::property_tree::ptree_bad_data>'
  what():  conversion of data to type "j" failed