Setup environment
1. Install CMake
cd ~
wget https://github.com/Kitware/CMake/releases/download/v3.14.5/cmake-3.14.5.tar.gz
tar xf cmake-3.14.5.tar.gz
cd cmake-3.14.5
./bootstrap --parallel=10
make -j4
sudo make -j4 install
2. Install Boost
cd ~
wget https://boostorg.jfrog.io/artifactory/main/release/1.69.0/source/boost_1_69_0.tar.gz
tar xf boost_1_69_0.tar.gz
cd boost_1_69_0
./bootstrap.sh
./b2 ... cxxflags="-std=c++0x -stdlib=libc++" linkflags="-stdlib=libc++" ...
sudo ./b2 toolset=gcc -j4 install
CMakeLists.txt
# Defines AppBase library target.
project(recipe_01)
cmake_minimum_required(VERSION 3.5)
include(GNUInstallDirs)
set(CMAKE_EXPORT_COMPILE_COMMANDS "ON")
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})
if(CMAKE_CXX_STANDARD EQUAL 98 OR CMAKE_CXX_STANDARD LESS 14)
message(FATAL_ERROR "app requires c++14 or newer")
elseif(NOT CMAKE_CXX_STANDARD)
set(CMAKE_CXX_STANDARD 14)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
endif()
find_package(Boost 1.60 REQUIRED COMPONENTS regex)
add_executable(main main.cpp)
target_link_libraries(main Boost::regex)
main.cpp
#include <boost/regex.hpp>
#include <iostream>
int main() {
// output the available regex syntaxes
std::cout
<< "Available regex syntaxes:\n"
<< "\t[0] Perl\n"
<< "\t[1] Perl case insensitive\n"
<< "\t[2] POSIX extended\n"
<< "\t[3] POSIX extended case insensitive\n"
<< "\t[4] POSIX basic\n"
<< "\t[5] POSIX basic case insensitive\n"
<< "Choose regex syntax: ";
// correctly set up flags, according to the chosen syntax
boost::regex::flag_type flag;
switch (std::cin.get()) {
case '0': flag = boost::regex::perl;
break;
case '1': flag = boost::regex::perl|boost::regex::icase;
break;
case '2': flag = boost::regex::extended;
break;
case '3': flag = boost::regex::extended|boost::regex::icase;
break;
case '4': flag = boost::regex::basic;
break;
case '5': flag = boost::regex::basic|boost::regex::icase;
break;
default:
std::cout << "Incorrect number of regex syntax. Exiting... \n";
return -1;
}
// Disabling exceptions
flag |= boost::regex::no_except;
//requesting regex patterns in a loop
// Restoring std::cin
std::cin.ignore();
std::cin.clear();
//Getting a String to match: in a loop
std::string regex, str;
do {
std::cout << "Input regex: ";
if (!std::getline(std::cin, regex) || regex.empty()) {
return 0;
}
// Without `boost::regex::no_except`flag this
// constructor may throw
const boost::regex e(regex, flag);
if (e.status()) {
std::cout << "Incorrect regex pattern!\n";
continue;
}
std::cout << "String to match: ";
while (std::getline(std::cin, str) && !str.empty()) {
bool matched = boost::regex_match(str, e);
std::cout << (matched ? "MATCH\n" : "DOES NOT MATCH\n");
std::cout << "String to match: ";
} // end of `while (std::getline(std::cin, str))`
std::cout << '\n';
// Restoring std::cin
std::cin.ignore();
std::cin.clear();
} while (1);
return 0;
} // int main()
To build
mkdir build
cd build
cmake ..
cmake --build .
And I get this error:
Scanning dependencies of target main
[ 50%] Building CXX object CMakeFiles/main.dir/main.cpp.o
[100%] Linking CXX executable bin/main
CMakeFiles/main.dir/main.cpp.o: In function `bool boost::regex_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, char, boost::regex_traits<char, boost::cpp_regex_traits<char> > >(__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, __gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::match_results<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >&, boost::basic_regex<char, boost::regex_traits<char,
boost::cpp_regex_traits<char> > > const&, boost::regex_constants::_match_flags)':
main.cpp:(.text._ZN5boost11regex_matchIN9__gnu_cxx17__normal_iteratorIPKcNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEESaINS_9sub_matchISB_EEEcNS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEEEbT_SJ_RNS_13match_resultsISJ_T0_EERKNS_11basic_regexIT1_T2_EENS_15regex_constants12_match_flagsE[_ZN5boost11regex_matchIN9__gnu_cxx17__normal_iteratorIPKcNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEESaINS_9sub_matchISB_EEEcNS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEEEbT_SJ_RNS_13match_resultsISJ_T0_EERKNS_11basic_regexIT1_T2_EENS_15regex_constants12_match_flagsE]+0x8f): undefined reference to `boost::re_detail_106900::perl_matcher<__gnu_cxx::__normal_iterator<char const*,
std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::match()'
CMakeFiles/main.dir/main.cpp.o: In function `boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::assign(char const*, char const*, unsigned int)':
main.cpp:(.text._ZN5boost11basic_regexIcNS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEE6assignEPKcS7_j[_ZN5boost11basic_regexIcNS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEE6assignEPKcS7_j]+0x2a): undefined reference to `boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::do_assign(char const*, char const*,
unsigned int)'
CMakeFiles/main.dir/main.cpp.o: In function `boost::re_detail_106900::perl_matcher<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::perl_matcher(__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, __gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>
> >, boost::match_results<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >&, boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char> > > const&, boost::regex_constants::_match_flags, __gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >)':
main.cpp:(.text._ZN5boost16re_detail_10690012perl_matcherIN9__gnu_cxx17__normal_iteratorIPKcNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEESaINS_9sub_matchISC_EEENS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEEC2ESC_SC_RNS_13match_resultsISC_SF_EERKNS_11basic_regexIcSJ_EENS_15regex_constants12_match_flagsESC_[_ZN5boost16re_detail_10690012perl_matcherIN9__gnu_cxx17__normal_iteratorIPKcNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEESaINS_9sub_matchISC_EEENS_12regex_traitsIcNS_16cpp_regex_traitsIcEEEEEC5ESC_SC_RNS_13match_resultsISC_SF_EERKNS_11basic_regexIcSJ_EENS_15regex_constants12_match_flagsESC_]+0x121): undefined reference to `boost::re_detail_106900::perl_matcher<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::construct_init(boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char> > > const&, boost::regex_constants::_match_flags)'
collect2: error: ld returned 1 exit status
CMakeFiles/main.dir/build.make:84: recipe for target 'bin/main' failed
make[2]: *** [bin/main] Error 1
CMakeFiles/Makefile2:72: recipe for target 'CMakeFiles/main.dir/all' failed
make[1]: *** [CMakeFiles/main.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2
I can not link to boost:regex with main function
Could you please tell me any solution for this issue?
I find some quote like
The boost 1.61 (and higher) are compiled with newer compilers, which use the _GLIBCXX_USE_CXX11_ABI=1 .. heh ABI. Meaning that for -std=c++11 std::basic_string... becomes std::__cxx11::basic_string... (and likewise for std::list; see the gcc Dual ABI documentation).
Since your linker error claims there is a missing symbol that contains std::string (which is short for std::basic_string<char,std::char_traits,std::allocator>), you are either compiling with a compiler that is too old and uses ABI 0, or you are even compiling explicitly with -D_GLIBCXX_USE_CXX11_ABI=0.
But how can I fix in my code?
Change the line
target_link_libraries(main Boost::regex)
to
target_link_libraries(main boost_regex)
And depending on your distro you may need to install some Boost devel packages.
Related
I developed a web server with C++ and here is a function, which caused a coredump issue but I don't know why.
bool MyClass::hasFamilyAdminPermission(uint32_t uid) {
ReadMutex mutex(&m_mtx); // this is read lock to lock m_familyOwner and m_familyAdmins
if (uid == m_familyOwner) {
return true;
}
std::vector<std::string> fields;
boost::split(fields, m_familyAdmins, boost::is_any_of(","));
std::string uidStr = boost::lexical_cast<string>(uid);
for (std::vector<std::string>::iterator itor = fields.begin(); itor != fields.end(); ++itor) {
if (uidStr == *itor) {
return true;
}
}
return false;
}
After executing gdb ./myServer coredump_file, I got the output as below:
warning: Unexpected size of section `.reg-xstate/8717' in core file.
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `./myServer'.
Program terminated with signal SIGABRT, Aborted.
warning: Unexpected size of section `.reg-xstate/8717' in core file.
#0 0x00007f627b2c5428 in __GI_raise (sig=sig#entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
54 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
[Current thread is 1 (Thread 0x7f62277fe700 (LWP 8717))]
(gdb) where
#0 0x00007f627b2c5428 in __GI_raise (sig=sig#entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007f627b2c702a in __GI_abort () at abort.c:89
#2 0x00007f627b3077ea in __libc_message (do_abort=do_abort#entry=2, fmt=fmt#entry=0x7f627b420ed8 "*** Error in `%s': %s: 0x%s ***\n")
at ../sysdeps/posix/libc_fatal.c:175
#3 0x00007f627b31037a in malloc_printerr (ar_ptr=<optimized out>, ptr=<optimized out>,
str=0x7f627b420fa0 "double free or corruption (fasttop)", action=3) at malloc.c:5006
#4 _int_free (av=<optimized out>, p=<optimized out>, have_lock=0) at malloc.c:3867
#5 0x00007f627b31453c in __GI___libc_free (mem=<optimized out>) at malloc.c:2968
#6 0x00007f627be650b4 in std::basic_string<char, std::char_traits<char>, std::allocator<char> >::~basic_string() ()
from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#7 0x000000000046acc1 in boost::as_literal<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > (r=...)
at /usr/local/include/boost/range/as_literal.hpp:102
#8 boost::algorithm::iter_split<std::vector<std::string, std::allocator<std::string> >, std::string, boost::algorithm::detail::token_finderF<boost::algorithm::detail::is_any_ofF<char> > > (Result=..., Input="604679400,1430691907,2792989999",
Finder=<error reading variable: DWARF-2 expression error: DW_OP_reg operations must be used either alone or in conjunction with DW_OP_piece or DW_OP_bit_piece.>) at /usr/local/include/boost/algorithm/string/iter_find.hpp:153
#9 0x0000000000464c17 in boost::algorithm::split<std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, std::string, boost::algorithm::detail::is_any_ofF<char> > (eCompress=<optimized out>, Pred=..., Input=..., Result=...) at /usr/local/include/boost/algorithm/string/split.hpp:149
#10 server::myServer::MyClass::hasFamilyAdminPermission (this=0x7f621c066dd0, uid=<optimized out>) at MyClass.cpp:202
#11 0x0000000000435678 in server::myServer::ServerAPI::onSetMicDataReq (this=0x7fff6da7e750, uid=1430691907, req=0x7f621c094200)
at ServerAPI.cpp:2291
So it seems that boost::split caused the coredump.
In gdb, I've done as below:
(gdb) frame 10
#10 server::myServer::MyClass::hasFamilyAdminPermission (this=0x7f621c066dd0, uid=<optimized out>) at MyClass.cpp:202
202 MyClass.cpp: No such file or directory.
(gdb) print fields
$1 = std::vector of length 0, capacity 0
For now, fields is an empty vector.
(gdb) frame 8
#8 boost::algorithm::iter_split<std::vector<std::string, std::allocator<std::string> >, std::string, boost::algorithm::detail::token_finderF<boost::algorithm::detail::is_any_ofF<char> > > (Result=..., Input="604679400,1430691907,2792989999",
Finder=<error reading variable: DWARF-2 expression error: DW_OP_reg operations must be used either alone or in conjunction with DW_OP_piece or DW_OP_bit_piece.>) at /usr/local/include/boost/algorithm/string/iter_find.hpp:153
153 /usr/local/include/boost/algorithm/string/iter_find.hpp: No such file or directory.
Here, the input is "604679400,1430691907,2792989999", which looks like ok.
However, when I execute info loclas (I'm still at the frame 8), I got a segmentation fault.
(gdb) info locals
Tmp = std::vector of length 1891892, capacity 1891893 = {<error reading variable Tmp (Cannot access memory at address 0x0)>
itBegin = {<boost::iterator_adaptor<boost::transform_iterator<boost::algorithm::detail::copy_iterator_rangeF<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, boost::algorithm::split_iterator<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, boost::use_default, boost::use_default>, boost::algorithm::split_iterator<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::use_default, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::use_default>> = {<boost::iterator_facade<boost::transform_iterator<boost::algorithm::detail::copy_iterator_rangeF<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, boost::algorithm::split_iterator<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, boost::use_default, boost::use_default>, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::forward_traversal_tag, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, long>> = {<No data fields>},
m_iterator = {<boost::iterator_facade<boost::algorithm::split_iterator<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, boost::iterator_range<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const, boost::forward_traversal_tag, boost::iterator_range<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&, long>> = {<No data fields>}, <boost::algorithm::detail::find_iterator_base<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >> = {
m_Finder = {<boost::function_base> = {vtable = 0x89bd9dd2, functor = {obj_ptr = 0x7f627b31453c <__GI___libc_free+76>, type = {
type = 0x7f627b31453c <__GI___libc_free+76>, const_qualified = false, volatile_qualified = false},
func_ptr = 0x7f627b31453c <__GI___libc_free+76>, bound_memfunc_ptr = {
memfunc_ptr = (void (boost::detail::function::X::*)(boost::detail::function::X * const,
int)) 0x7f627b31453c <__GI___libc_free+76>, obj_ptr = 0xe8436c057b9e1300}, obj_ref = {obj_ptr = 0x7f627b31453c <__GI___libc_free+76>,
is_const_qualified = false, is_volatile_qualified = false},
data = 60 '<'}}, <std::binary_function<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, __gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::iterator_range<__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >> = {<No data fields>},
/usr/bin/sudo: line 11: 75240 Segmentation fault (core dumped) ${SUDO} $#
I don't know what caused the coredump, I don't know either why I got the segmentation fault after executing info locals...
So, boost::split doesn't crash. You have undefined behavior elsewhere.
Regardless, why are you parsing through a string, allocating a vector of strings, comparing to a temporary string etc. all the time? You could do this on the integer-domain.
Four takes. Starting from a simple skeleton:
#include <shared_mutex>
#include <string>
struct MyClass1 {
MyClass1(uint32_t owner, std::string admins)
: m_familyOwner(owner)
, m_familyAdmins(std::move(admins)) {}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
std::string m_familyAdmins;
};
1. Comparing Ints, No Allocations
I'll use Boost Spirit X3:
#include <boost/spirit/home/x3.hpp>
bool MyClass1::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
if (uid == m_familyOwner)
return true;
bool matched = false;
auto element = boost::spirit::x3::uint32;
auto check = [uid, &matched](auto& ctx) {
if (_attr(ctx) == uid) {
matched = true;
_pass(ctx) = false; // short circuit for perf
}
};
parse(begin(m_familyAdmins), end(m_familyAdmins), element[check] % ',');
return matched;
}
This still does quite a lot of work under the lock, but certainly never allocates. Also, it does early-out, which helps if the collection of owners can be very large.
2. Comparing Text, But Without Allocations
With a nifty regex you can match the number as text on a constant string (or string view). The overhead here is the allocation(s) for the regex. But arguably, it's much simpler:
#include <regex>
bool MyClass2::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
if (uid == m_familyOwner)
return true;
return regex_search(m_familyAdmins, std::regex("(^|,)" + std::to_string(uid) + "(,|$)"));
}
3. Parse Once, At Construction
Why are we dealing with text? We could keep the admins in a set:
#include <set>
struct MyClass3 {
MyClass3(uint32_t owner, std::string_view admins) : m_familyOwner(owner) {
parse(admins.begin(), end(admins), boost::spirit::x3::uint32 % ',', m_familyAdmins);
}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
std::set<uint32_t> m_familyAdmins;
};
bool MyClass3::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
return uid == m_familyOwner || m_familyAdmins.contains(uid);
}
That's even simpler. However, there's some overhead in the set which can be optimized.
4. Parse Once, No Allocations, Speed
std::set has the right semantics. However, for small sets it's sad that there's no locality of reference, and relatively high node allocation overhead. We could replace with:
boost::container::flat_set< //
uint32_t, //
std::less<>, //
boost::container::small_vector<uint32_t, 10>>
m_familyAdmins;
This makes it so that sets <= 10 elements do not allocate at all, and lookup benefits from contiguous storage. However, at this rate - unless you want to deal with duplicate entries - you might keep a linear search and store:
boost::container::small_vector<uint32_t, 10>
m_familyAdmins;
Combined Demo
Showing all the subtle edge cases. Note that only with the X3 parser
it will be easy to perform input validation on the comma-separated string
it will be easy to reliably compare differently formatted uid numbers
I snuck in one number that has a leading 0 (089 instead of 89) just to highlight this issue with the std::regex approach. Note that your original code has the same problem.
Live On Coliru/Compiler Explorer
#include <shared_mutex>
#include <string>
struct MyClass1 {
MyClass1(uint32_t owner, std::string admins)
: m_familyOwner(owner)
, m_familyAdmins(std::move(admins)) {}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
std::string m_familyAdmins;
};
#include <boost/spirit/home/x3.hpp>
bool MyClass1::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
if (uid == m_familyOwner)
return true;
bool matched = false;
auto element = boost::spirit::x3::uint32;
auto check = [uid, &matched](auto& ctx) {
if (_attr(ctx) == uid) {
matched = true;
_pass(ctx) = false; // short circuit for perf
}
};
parse(begin(m_familyAdmins), end(m_familyAdmins), element[check] % ',');
return matched;
}
struct MyClass2 {
MyClass2(uint32_t owner, std::string admins)
: m_familyOwner(owner)
, m_familyAdmins(std::move(admins)) {}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
std::string m_familyAdmins;
};
#include <regex>
bool MyClass2::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
if (uid == m_familyOwner)
return true;
return std::regex_search(m_familyAdmins, std::regex("(^|,)" + std::to_string(uid) + "(,|$)"));
}
#include <set>
struct MyClass3 {
MyClass3(uint32_t owner, std::string_view admins) : m_familyOwner(owner) {
parse(admins.begin(), end(admins), boost::spirit::x3::uint32 % ',', m_familyAdmins);
}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
std::set<uint32_t> m_familyAdmins;
};
bool MyClass3::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
return uid == m_familyOwner || m_familyAdmins.contains(uid);
}
#include <boost/container/flat_set.hpp>
#include <boost/container/small_vector.hpp>
struct MyClass4 {
MyClass4(uint32_t owner, std::string_view admins) : m_familyOwner(owner) {
parse(admins.begin(), end(admins), boost::spirit::x3::uint32 % ',', m_familyAdmins);
}
bool hasFamilyAdminPermission(uint32_t uid) const;
private:
mutable std::shared_mutex m_mtx; // guards m_familyOwner and m_familyAdmins
uint32_t m_familyOwner;
#ifdef LINEAR_SEARCH
// likely faster with small sets, anyways
boost::container::small_vector<uint32_t, 10> m_familyAdmins;
#else
boost::container::flat_set< //
uint32_t, //
std::less<>, //
boost::container::small_vector<uint32_t, 10>>
m_familyAdmins;
#endif
};
bool MyClass4::hasFamilyAdminPermission(uint32_t uid) const {
std::shared_lock mutex(m_mtx);
return uid == m_familyOwner ||
#ifndef LINEAR_SEARCH
std::find(begin(m_familyAdmins), end(m_familyAdmins), uid) != end(m_familyAdmins);
#else
m_familyAdmins.contains(uid);
#endif
}
#include <iostream>
int main() {
MyClass1 const mc1{42, "21,377,34,233,55,089,144"};
MyClass2 const mc2{42, "21,377,34,233,55,089,144"};
MyClass3 const mc3{42, "21,377,34,233,55,089,144"};
MyClass4 const mc4{42, "21,377,34,233,55,089,144"};
std::cout << "uid\tdynamic\tregex\tset\tflat_set\n"
<< "\t(x3)\t-\t(x3)\t(x3)\n"
<< std::string(5 * 8, '-') << "\n";
auto compare = [&](uint32_t uid) {
std::cout << uid << "\t" << std::boolalpha
<< mc1.hasFamilyAdminPermission(uid) << "\t"
<< mc2.hasFamilyAdminPermission(uid) << "\t"
<< mc3.hasFamilyAdminPermission(uid) << "\t"
<< mc4.hasFamilyAdminPermission(uid) << "\n";
};
compare(42);
// https://en.wikipedia.org/wiki/Fibonacci_number
for (auto i = 3, j = 5; i < 800; std::tie(i, j) = std::tuple{j, i + j}) {
compare(i);
}
}
Prints
id dynamic regex set flat_set
(x3) - (x3) (x3)
----------------------------------------
42 true true true true
3 false false false false
5 false false false false
8 false false false false
13 false false false false
21 true true true true
34 true true true true
55 true true true true
89 true false true true
144 true true true true
233 true true true true
377 true true true true
610 false false false false
When compiling a program with opencv2, I'm getting a weird compiler error with ld. I'm unable to find anything online to do with the error.
I'm using this command to compile the program
g++ -Wall Tracker.cpp -o Tracker
and I'm getting this output from the compiler
Tracker.cpp: In function ‘int main(int, char**)’:
Tracker.cpp:60:10: warning: unused variable ‘ok’ [-Wunused-variable]
60 | bool ok = video.read(frame);
| ^~
/usr/bin/ld: /tmp/cc2Q6W8D.o: in function `main':
Tracker.cpp:(.text+0x29d): undefined reference to `cv::VideoCapture::VideoCapture(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, int)'
/usr/bin/ld: Tracker.cpp:(.text+0x2ca): undefined reference to `cv::VideoCapture::isOpened() const'
/usr/bin/ld: Tracker.cpp:(.text+0x34a): undefined reference to `cv::VideoCapture::read(cv::_OutputArray const&)'
/usr/bin/ld: Tracker.cpp:(.text+0x425): undefined reference to `cv::rectangle(cv::_InputOutputArray const&, cv::Rect_<int>, cv::Scalar_<double> const&, int, int, int)'
/usr/bin/ld: Tracker.cpp:(.text+0x492): undefined reference to `cv::imshow(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::_InputArray const&)'
/usr/bin/ld: Tracker.cpp:(.text+0x503): undefined reference to `cv::Tracker::init(cv::_InputArray const&, cv::Rect_<double> const&)'
/usr/bin/ld: Tracker.cpp:(.text+0x544): undefined reference to `cv::VideoCapture::read(cv::_OutputArray const&)'
/usr/bin/ld: Tracker.cpp:(.text+0x562): undefined reference to `cv::getTickCount()'
/usr/bin/ld: Tracker.cpp:(.text+0x5b3): undefined reference to `cv::Tracker::update(cv::_InputArray const&, cv::Rect_<double>&)'
/usr/bin/ld: Tracker.cpp:(.text+0x5cd): undefined reference to `cv::getTickFrequency()'
/usr/bin/ld: Tracker.cpp:(.text+0x5da): undefined reference to `cv::getTickCount()'
/usr/bin/ld: Tracker.cpp:(.text+0x697): undefined reference to `cv::rectangle(cv::_InputOutputArray const&, cv::Rect_<int>, cv::Scalar_<double> const&, int, int, int)'
/usr/bin/ld: Tracker.cpp:(.text+0x772): undefined reference to `cv::putText(cv::_InputOutputArray const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::Point_<int>, int, double, cv::Scalar_<double>, int, int, bool)'
/usr/bin/ld: Tracker.cpp:(.text+0x86e): undefined reference to `cv::putText(cv::_InputOutputArray const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::Point_<int>, int, double, cv::Scalar_<double>, int, int, bool)'
/usr/bin/ld: Tracker.cpp:(.text+0x9ab): undefined reference to `cv::putText(cv::_InputOutputArray const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::Point_<int>, int, double, cv::Scalar_<double>, int, int, bool)'
/usr/bin/ld: Tracker.cpp:(.text+0xa49): undefined reference to `cv::imshow(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::_InputArray const&)'
/usr/bin/ld: Tracker.cpp:(.text+0xa80): undefined reference to `cv::waitKey(int)'
/usr/bin/ld: Tracker.cpp:(.text+0xab8): undefined reference to `cv::VideoCapture::~VideoCapture()'
/usr/bin/ld: Tracker.cpp:(.text+0xe35): undefined reference to `cv::VideoCapture::~VideoCapture()'
/usr/bin/ld: /tmp/cc2Q6W8D.o: in function `cv::Mat::~Mat()':
Tracker.cpp:(.text._ZN2cv3MatD2Ev[_ZN2cv3MatD5Ev]+0x39): undefined reference to `cv::fastFree(void*)'
/usr/bin/ld: /tmp/cc2Q6W8D.o: in function `cv::Mat::release()':
Tracker.cpp:(.text._ZN2cv3Mat7releaseEv[_ZN2cv3Mat7releaseEv]+0x4b): undefined reference to `cv::Mat::deallocate()'
collect2: error: ld returned 1 exit status
Tracker.cpp
#include <opencv2/opencv.hpp>
#include <opencv2/tracking.hpp>
#include <opencv2/core/ocl.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui/highgui.hpp>
using namespace cv;
using namespace std;
// Convert to string
#define SSTR( x ) static_cast< std::ostringstream & >(( std::ostringstream() << std::dec << x )).str()
int main(int argc, char **argv)
{
// List of tracker types in OpenCV 3.4.1
string trackerTypes[8] = {"BOOSTING", "MIL", "KCF", "TLD","MEDIANFLOW", "GOTURN", "MOSSE", "CSRT"};
// vector <string> trackerTypes(types, std::end(types));
// Create a tracker
string trackerType = trackerTypes[2];
Ptr<Tracker> tracker;
#if (CV_MINOR_VERSION < 3)
{
// tracker = Tracker::create(trackerType);
}
#else
{
if (trackerType == "BOOSTING")
tracker = TrackerBoosting::create();
if (trackerType == "MIL")
tracker = TrackerMIL::create();
if (trackerType == "KCF")
tracker = TrackerKCF::create();
if (trackerType == "TLD")
tracker = TrackerTLD::create();
if (trackerType == "MEDIANFLOW")
tracker = TrackerMedianFlow::create();
if (trackerType == "GOTURN")
tracker = TrackerGOTURN::create();
if (trackerType == "MOSSE")
tracker = TrackerMOSSE::create();
if (trackerType == "CSRT")
tracker = TrackerCSRT::create();
}
#endif
// Read video
VideoCapture video("videos/test.mp4");
// Exit if video is not opened
if(!video.isOpened())
{
cout << "Could not read video file" << endl;
return 1;
}
// Read first frame
Mat frame;
bool ok = video.read(frame);
// Define initial bounding box
Rect2d bbox(287, 23, 86, 320);
// Uncomment the line below to select a different bounding box
//bbox = selectROI(frame, false);
// Display bounding box.
rectangle(frame, bbox, Scalar( 255, 0, 0 ), 2, 1 );
imshow("Tracking", frame);
tracker->init(frame, bbox);
while(video.read(frame))
{
// Start timer
double timer = (double)getTickCount();
// Update the tracking result
bool ok = tracker->update(frame, bbox);
// Calculate Frames per second (FPS)
float fps = getTickFrequency() / ((double)getTickCount() - timer);
if (ok)
{
// Tracking success : Draw the tracked object
rectangle(frame, bbox, Scalar( 255, 0, 0 ), 2, 1 );
}
else
{
// Tracking failure detected.
putText(frame, "Tracking failure detected", Point(100,80), FONT_HERSHEY_SIMPLEX, 0.75, Scalar(0,0,255),2);
}
// Display tracker type on frame
putText(frame, trackerType + " Tracker", Point(100,20), FONT_HERSHEY_SIMPLEX, 0.75, Scalar(50,170,50),2);
// Display FPS on frame
putText(frame, "FPS : " + SSTR(int(fps)), Point(100,50), FONT_HERSHEY_SIMPLEX, 0.75, Scalar(50,170,50), 2);
// Display frame.
imshow("Tracking", frame);
// Exit if ESC pressed.
int k = waitKey(1);
if(k == 27)
{
break;
}
}
}
I've never seen this sort of error before and i'm not sure what's causing it, any help would be great.
Looks like you forgot to link, maybe something like:
g++ -Wall Tracker.cpp -o Tracker -lopencv_core -lopencv_imgproc -lopencv_dnn -lopencv_highgui
You might have to add -lopencv_videoio as well depending on version
I'm working on code that runs on a raspberry pi 3. And got the following error on my logging classes.
==1297== Invalid read of size 8
==1297== at 0x4865D1C: ??? (in /usr/lib/arm-linux-gnueabihf/libarmmem.so)
==1297== Address 0x4c8d45c is 100 bytes inside a block of size 107 alloc'd
==1297== at 0x4847DA4: operator new(unsigned int) (vg_replace_malloc.c:328)
==1297== by 0x49C3D9B: std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::reserve(unsigned int) (in /usr/lib/arm-linux-gnueabihf/libstdc++.so.6.0.22)
==1297== by 0x4AE65: std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::operator+<char, std::char_traits<char>, std::allocator<char> >(char const*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (basic_string.tcc:1155)
==1297== by 0xF82B5: Log::Book::addField(std::unique_ptr<Log::Entry, std::default_delete<Log::Entry> >&, unsigned int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (LogBook.cpp:149)
==1297== by 0xF7CCB: Log::Book::record(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, int, unsigned int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::chrono::time_point<std::chrono::_V2::system_clock, std::chrono::duration<long long, std::ratio<1ll, 1000000000ll> > >) (LogBook.cpp:87)
GCC version: gcc version 6.3.0 20170516 (Raspbian 6.3.0-18+rpi1+deb9u1)
valgrind version: valgrind-3.13.0
I can't seem to locate the problem since the function Log::Book::record() get it's value via pass-by-value. I can also say that this error isn't always shown when the function is called. It is deterministic in the sense of on what line the error shows and on what line not. Can anybody direct my in direction of what this problem is and the solution for it? Code snippet below with a comment of the indicated lines.
/** log message */
void Book::record(std::string file, const int line, const unsigned int level, Identifier id, const std::string message,
const std::chrono::high_resolution_clock::time_point timeStamp)
{
if (!(fileLevels & level) && !(consoleLevels & level)) { return; }
auto now = Time::keeper->now();
auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(timeStamp - Time::globalEpoch);
//generate message
auto entry = std::make_unique<Entry>(level);
// Time since startup
addField(entry, 0, std::to_string(duration.count()));
//UTC Time
addField(entry, 1, now.dateTime());
// File
std::string stringFile;
if (!file.empty())
{
stringFile = URL{file}.lastPathComponent();
}
addField(entry, 2, stringFile);
//Line number
addField(entry, 3, std::to_string(line));
//ID
addField(entry, 4, id);
//Message
std::string stringMessage;
if(!message.empty())
{
addField(entry, 5, message); //this is line LogBook.cpp:87
}
else
{
addField(entry, 5, " empty message.");
}
*entry << ";";
//queue message
this->append(std::move(entry));
}
void Book::addField(std::unique_ptr<Entry> &entry, unsigned int index, const std::string &text)
{
std::string textOutput;
if ((spacings.at(index) != 0) && (text.length() > (spacings.at(index) - 1)))
{
spacings.at(index) = (uint8_t) (text.length() + 2);
}
entry->setWidth(spacings.at(index));
if(entry->empty())
textOutput = text;
else
textOutput = ";" + text; //This is line LogBook.cpp:149
if(!textOutput.empty())
(*entry) << textOutput;
}
The code where this function gets called and this problem occurs.
auto node = child(items, "item", index);
auto enabled = boolValue(node, "enabled", false);
auto file = pathValue(node, key::path);
auto name = stringValue(node, "name", "");
auto type = stringValue(node, "type");
CLOG(CLOG::WARNING, "Yard item " + name + " not enabled, path:" + file.path());
Update 1:
I compile with cmake with the options. And added extra options. These didn't solve the problem.
add_compile_options(-ggdb)
add_compile_options(-O1)
#Extra disable vectorization
add_compile_options(-fno-tree-vectorize)
add_compile_options(-fno-tree-loop-vectorize)
add_compile_options(-fno-tree-slp-vectorize)
Update 2:
I've found an other place where string concatenation is used and valgrind reports te same errors
Update 3:
Some time and interesting discoveries later.
Error happens in a shared library libarmmem.so. This gets dynamically loaded and is by this reason always on a different address. Used gdb and valgrind combination to break when the error happens.
gdb loaded shared libraries with starting address.
(gdb) info sharedlibrary
From To Syms Read Shared Object Library
0x0483246c 0x04832750 Yes /usr/local/lib/valgrind/vgpreload_core-arm-linux.so
0x04846e60 0x04850c10 Yes /usr/local/lib/valgrind/vgpreload_memcheck-arm-linux.so
0x04863588 0x048672fc Yes (*) /usr/lib/arm-linux-gnueabihf/libarmmem.so
...
Error reported by valgrind.
==9442== Invalid read of size 8
==9442== at 0x4865D34: ??? (in /usr/lib/arm-linux-gnueabi/libarmmem.so)
We know from readelf of libarmmem.so that the .text section begins on 588. and that memcpy sits on 710. The disassembly on this breakpoint shows we are in memcpy on address 0x04863710. If we check the range like : 0x04863588 - 0x04863710 = 188. 188 + 588(starting adress of .text) = 710.
Disassembly shows it happens on a assembly line. vldmia is a instruction for Load Vector Floating Point registers.
0x04865d34 <+9764>: vldmia r1!, {d9}
No solution yet.
Most probly the code inside libarmem.so has been vectorized in such a way that it realizes that there's a terminating char only after reading full 8-byte chunk. This will not trigger a processor exception (as algorithm ensures that pointer is aligned and thus stays in the same page) but will cause tools like Valgrind to report false positives.
Problems like this are getting worse over time and making Valgrind less useful in practice. See Valgrind vs Optimising Compilers for an in-depth discussion or this bug in diff for real-world example (or my Debian suppression list for even more examples).
I get the following runtime error message
terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::wave::cpplexer::lexing_exception> >'
what(): boost::wave::lexing_exception
When I am trying to run the following code:
#include <vector>
#include <algorithm>
#include <boost/wave.hpp>
#include <boost/wave/cpplexer/cpp_lex_token.hpp>
#include <boost/wave/cpplexer/cpp_lex_iterator.hpp>
std::string strip_comments(std::string const& input)
{
std::string output;
typedef boost::wave::cpplexer::lex_token<> token_type;
typedef boost::wave::cpplexer::lex_iterator<token_type> lexer_type;
typedef token_type::position_type position_type;
position_type pos;
lexer_type it = lexer_type(input.begin(), input.end(), pos,
boost::wave::language_support(
boost::wave::support_cpp|boost::wave::support_option_long_long));
lexer_type end = lexer_type();
for (;it != end; ++it)
{
if (*it != boost::wave::T_CCOMMENT
&& *it != boost::wave::T_CPPCOMMENT)
{
output += std::string(it->get_value().begin(), it->get_value().end());
}
}
return output;
}
int main()
{
std::string text="aaa bbb /*cccc*/ ddd // eee";
std::cout<<strip_comments(text)<<std::endl;
return 0;
}
I use gcc compiler:
g++ -std=c++11 test.cpp -o test -lboost_wave -lboost_system
This code is supposed to remove C++ comments from a text specified by // and /* ... */.
Here is gdb backtrack:
GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.2) 7.7.1
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from a.out...done.
[New LWP 10573]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `./a.out'.
Program terminated with signal SIGABRT, Aborted.
#0 0x00007ff38fe96cc9 in __GI_raise (sig=sig#entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
56 ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 0x00007ff38fe96cc9 in __GI_raise (sig=sig#entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1 0x00007ff38fe9a0d8 in __GI_abort () at abort.c:89
#2 0x00007ff3904cb78d in __gnu_cxx::__verbose_terminate_handler() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#3 0x00007ff3904c97f6 in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#4 0x00007ff3904c9841 in std::terminate() () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#5 0x00007ff3904c9a58 in __cxa_throw () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#6 0x00007ff390a9e063 in void boost::throw_exception<boost::wave::cpplexer::lexing_exception>(boost::wave::cpplexer::lexing_exception const&)
() from /usr/lib/x86_64-linux-gnu/libboost_wave.so.1.54.0
#7 0x00007ff390aa3a5e in boost::wave::cpplexer::re2clex::lexer<__gnu_cxx::__normal_iterator<char const*, std::string>, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > >, boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::report_error(boost::wave::cpplexer::re2clex::Scanner const*, int, char const*, ...) ()
from /usr/lib/x86_64-linux-gnu/libboost_wave.so.1.54.0
#8 0x00007ff390aaf2f0 in boost::wave::cpplexer::re2clex::scan(boost::wave::cpplexer::re2clex::Scanner*) ()
from /usr/lib/x86_64-linux-gnu/libboost_wave.so.1.54.0
#9 0x00007ff390aa4329 in boost::wave::cpplexer::re2clex::lexer<__gnu_cxx::__normal_iterator<char const*, std::string>, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > >, boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::get(boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > >&) () from /usr/lib/x86_64-linux-gnu/libboost_wave.so.1.54.0
#10 0x000000000040a3b8 in boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::get_next<boost::spirit::multi_pass<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::default_policy<boost::spirit::iterator_policies::ref_counted, boost::spirit::iterator_policies::no_check, boost::spirit::iterator_policies::split_functor_input, boost::spirit::iterator_policies::split_std_deque> > > (mp=..., result=...)
at /usr/include/boost/wave/cpplexer/cpp_lex_iterator.hpp:80
#11 0x0000000000409efb in boost::spirit::iterator_policies::split_functor_input::unique<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, true>::advance_input<boost::spirit::multi_pass<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util---Type <return> to continue, or q <return> to quit---
::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::default_policy<boost::spirit::iterator_policies::ref_counted, boost::spirit::iterator_policies::no_check, boost::spirit::iterator_policies::split_functor_input, boost::spirit::iterator_policies::split_std_deque> > > (mp=...)
at /usr/include/boost/spirit/home/support/iterators/detail/split_functor_input_policy.hpp:91
#12 0x000000000040969f in boost::spirit::iterator_policies::multi_pass_unique<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::ref_counted::unique, boost::spirit::iterator_policies::no_check::unique, boost::spirit::iterator_policies::split_functor_input::unique<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, true>, boost::spirit::iterator_policies::split_std_deque::unique<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, true, true, true>::advance_input<boost::spirit::multi_pass<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::default_policy<boost::spirit::iterator_policies::ref_counted, boost::spirit::iterator_policies::no_check, boost::spirit::iterator_policies::split_functor_input, boost::spirit::iterator_policies::split_std_deque> > > (mp=...)
at /usr/include/boost/spirit/home/support/iterators/detail/combine_policies.hpp:441
#13 0x0000000000408d7c in boost::spirit::iterator_policies::split_std_deque::unique<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::increment<boost::spirit::multi_pass<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::default_policy<boost::spirit::iterator_policies::ref_counted, boost::spirit::iterator_policies::no_check, boost::spirit::iterator_policies::split_functor_input, boost::spirit::iterator_policies::split_std_deque> > > (mp=...)
at /usr/include/boost/spirit/home/support/iterators/detail/split_std_deque_policy.hpp:107
#14 0x0000000000408450 in boost::spirit::multi_pass<std::pair<boost::wave::cpplexer::impl::lex_iterator_functor_shim<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >, boost::wave::cpplexer::lex_input_interface<boost:---Type <return> to continue, or q <return> to quit---
:wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >*>, boost::spirit::iterator_policies::default_policy<boost::spirit::iterator_policies::ref_counted, boost::spirit::iterator_policies::no_check, boost::spirit::iterator_policies::split_functor_input, boost::spirit::iterator_policies::split_std_deque> >::operator++ (this=0x7fff7d8f66e0)
at /usr/include/boost/spirit/home/support/iterators/multi_pass.hpp:119
#15 0x000000000040680e in strip_comments (input="aaa bbb /*cccc*/ ddd // eee") at test.cpp:23
#16 0x0000000000406927 in main () at test.cpp:37
Update
Thanks to jpo38 for his comment. I initialized the pos by
position_type pos(0);
And the previous runtime error fixed.
Now, I got a different runtime error:
#0 0x0000000000406ff8 in std::char_traits<char>::length (__s=0x0) at /usr/include/c++/4.9/bits/char_traits.h:263
#1 0x0000000000408504 in boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> >::flex_string (this=0x7ffee3d536a0, s=0x0, a=...)
at /usr/include/boost/wave/util/flex_string.hpp:1502
#2 0x000000000040693f in strip_comments (input="aaa bbb /*cccc*/ ddd // eee") at test.cpp:16
#3 0x0000000000406bf0 in main () at test.cpp:37
I catched the general exception and tried to show it by:
std::cout << "Error occurred: " << ex.what() << std::endl;
while it was not successful.
boost love exception-programming. Meaning exceptions are used to raise errors and warnings....I hate that, but you need to accept it if you use those fantastic c++ libraries. Exceptions lead to "crash" if you don't be careful and catch them, like that:
std::string strip_comments(std::string const& input)
{
std::string output;
typedef boost::wave::cpplexer::lex_token<> token_type;
typedef boost::wave::cpplexer::lex_iterator<token_type> lexer_type;
typedef token_type::position_type position_type;
boost::wave::util::file_position_type current_position; // for error reporting
try
{
position_type pos;
lexer_type it = lexer_type(input.begin(), input.end(), pos,
boost::wave::language_support(
boost::wave::support_cpp|boost::wave::support_option_long_long));
lexer_type end = lexer_type();
for (;it != end; ++it)
{
current_position = (*it).get_position(); // for error reporting
if (*it != boost::wave::T_CCOMMENT
&& *it != boost::wave::T_CPPCOMMENT)
{
output += std::string(it->get_value().begin(), it->get_value().end());
}
}
}
catch (boost::wave::cpplexer::lexing_exception const& e) {
// some lexing error
std::cerr
<< e.file_name() << "(" << e.line_no() << "): "
<< e.description() << std::endl;
}
catch (std::exception const& e) {
// use last recognized token to retrieve the error position
std::cerr
<< current_position.get_file()
<< "(" << current_position.get_line() << "): "
<< "exception caught: " << e.what()
<< std::endl;
}
catch (...) {
// use last recognized token to retrieve the error position
std::cerr
<< current_position.get_file()
<< "(" << current_position.get_line() << "): "
<< "unexpected exception caught." << std::endl;
}
return output;
}
Then, instead of a "crash", you'll get this nice ans safe message:
(1): warning: generic lexer warning: Unterminated 'C++' style comment
You can see that, by not catching exception, a simple boost warning was transformed in a critical crash at your level ;-)
I'm not familiar with wave library, but adding a \n to the end of your string fixes the issue and then no error is reported anymore (by the way, it was actually just a warning):
Change main function text string to: std::string text="aaa bbb /*cccc*/ ddd // eee\n"; and the program will output aaa bbb ddd.
You can add this \n, but you may also rework the code to try/catch within the loop and then report but ignore warnings.
Note: The fact that boost::wave expects a EOL is probably related to this well known C++ warning (but it is really just a warning): "No newline at end of file" compiler warning
im using gzip_decompressor() from the boost library but i'm getting a strange Segmentation fault on free().
stringstream gzMessage;
stringstream rawMessage;
gzMessage << (*iter)->message;
filtering_streambuf<input> gzFilter;
gzFilter.push(gzip_decompressor());
gzFilter.push(gzMessage);
boost::iostreams::copy(gzFilter, rawMessage);
message = rawMessage.str();
cout << "ungzipped: " << message << endl;
The line in question is boost::iostreams::copy(gzFilter, rawMessage);
if i comment this one out everything works fine.
the backtrace:
(gdb) bt
#0 0x00007ffff640fd29 in free () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x0000000000453f8c in boost::detail::sp_counted_impl_p<boost::iostreams::symmetric_filter<boost::iostreams::detail::zlib_decompressor_impl<std::allocator<char> >, std::allocator<char> >::impl>::dispose()
()
#2 0x0000000000427f49 in boost::detail::shared_count::~shared_count() ()
#3 0x00000000004598ae in boost::iostreams::stream_buffer<boost::iostreams::basic_gzip_decompressor<std::allocator<char> >, std::char_traits<char>, std::allocator<char>, boost::iostreams::input>::~stream_buffer() ()
#4 0x0000000000459c39 in boost::iostreams::detail::chain_base<boost::iostreams::chain<boost::iostreams::input, char, std::char_traits<char>, std::allocator<char> >, char, std::char_traits<char>, std::allocator<char>, boost::iostreams::input>::chain_impl::~chain_impl() ()
#5 0x0000000000459d12 in boost::detail::sp_counted_impl_p<boost::iostreams::detail::chain_base<boost::iostreams::chain<boost::iostreams::input, char, std::char_traits<char>, std::allocator<char> >, char, std::char_traits<char>, std::allocator<char>, boost::iostreams::input>::chain_impl>::dispose() ()
#6 0x0000000000427f49 in boost::detail::shared_count::~shared_count() ()
any hints ?