Boost::Regex Segfault (I think) - c++

Question

I'm having an issue with some C++ code that I'm running. Basically, it works fine with most inputs, but with certain inputs it segfaults after my main function returns. This has been... puzzling. I stopped the run at the segfault to get the stack trace, and it returned this:
#0 malloc_consolidate() at /build/eglibc-oGUzwX/eglibc-2.19/malloc/malloc.c:4151
#1 _int_free() at /build/eglibc-oGUzwX/eglibc-2.19/malloc/malloc.c:4057
#2 boost::re_detail::mem_block_cache::~mem_block_cache()() at /usr/lib/x86_64-linux-gnu/libboost_regex.so.1.54.0
#3 __cxa_finalize() at /build/eglibc-oGUzwX/eglibc-2.19/stdlib/cxa_finalize.c:56
#4 ??() at /usr/lib/x86_64-linux-gnu/libboost_regex.so.1.54.0
#5 ??() at
#6 _dl_fini() at /build/eglibc-oGUzwX/eglibc-2.19/elf/dl-fini.c:252
This made me think that I must be doing something wrong with boost regex, but I can't for the life of me figure it out. The way I'm using regex is that users can input a bunch of strings. Those strings could just be normal text, or they could be regular expressions. Because of this, I basically interact with all the inputs as regular expressions. But what if a user gave a string that was intended as plain text but had a character that could be interpreted differently as a regular expression? What I do is go through all plain text input strings and escape all those characters.
Here's the code that I'm working with. This is my main:
int
main(int argc, char * argv[])
{
// Process input arguments
// The desired input is numVertices (int), graph density (double between 0 and 1), halfLoss (double), total loss (double),
// position expanse (double, m), velocity expanse (double, m/s)
int num_vertices;
double graph_density ;
double half_loss;
double total_loss;
double position_expanse;
double velocity_expanse;
if (argc == 1)
{
num_vertices = 48;
graph_density = 1;
half_loss = 200000;
total_loss = 400000;
position_expanse = 400000;
velocity_expanse = 10000;
}
else
{
if (argc != 7)
{
std::cerr << "Need 6 input arguments" << std::endl;
return 1;
}
std::istringstream ss(argv[1]);
num_vertices;
if (!(ss >> num_vertices))
std::cerr << "First input must be an integer" << std::endl;
graph_density = read_double_input(argv[2]);
half_loss = read_double_input(argv[3]);
total_loss = read_double_input(argv[4]);
position_expanse = read_double_input(argv[5]);
velocity_expanse = read_double_input(argv[6]);
}
// Determine how many edges to create
int num_edges = (int) ( (graph_density * num_vertices * (num_vertices - 1)) + 0.5 );
// Create the edges
int edges_created = 0;
std::set<std::pair<int, int> > edge_set;
while (edge_set.size() < num_edges)
{
// Pick a random start vertex and end vertex
int start_vertex = rand() % num_vertices;
int end_vertex = rand() % num_vertices;
// Make sure the start and end vertices are not equal
while (start_vertex == end_vertex)
{
end_vertex = rand() % num_vertices;
}
// Insert the new edge into our set of edges
edge_set.insert(std::pair<int, int>(start_vertex, end_vertex));
}
// Create connection handler
ConnectionHandler conn_handler;
// Create lists for from and to vertices
std::vector<std::string> from_list;
std::vector<std::string> to_list;
// Add connections to from and to lists
for (std::set<std::pair<int, int> >::const_iterator edge_it = edge_set.begin(), end_it = edge_set.end(); edge_it != end_it; ++edge_it)
{
int start_vertex = edge_it->first;
int end_vertex = edge_it->second;
from_list.push_back("Radio" + int_to_string(start_vertex));
to_list.push_back("Radio" + int_to_string(end_vertex));
}
// Read the list into the connection handler
conn_handler.read_connection_list(true, from_list, to_list);
return 0;
}
This code has this ConnectionHandler object that I created. Here's the header for that:
#ifndef CLCSIM_CONNECTIONHANDLER_HPP_
#define CLCSIM_CONNECTIONHANDLER_HPP_
#include <models/network/NetworkTypes.hpp>
#include <generated/xsd/NetworkModelInterfaceConfig.hpp>
namespace clcsim
{
typedef std::map<std::string, std::set<std::string> > ConnectionFilter;
class ConnectionHandler
{
public:
ConnectionHandler();
~ConnectionHandler();
void read_connection_list(const bool is_white_list, const std::vector<std::string> &from_radios, const std::vector<std::string> &to_radios);
private:
ConnectionFilter filter_;
std::set<std::string> from_list_;
std::set<std::string> to_list_;
bool is_white_list_;
};
} // namespace clcsim
#endif // CLCSIM_CONNECTIONHANDLER_HPP_
And here's the source:
#include <models/network/ConnectionHandler.hpp>
#include <oasis/framework/exceptions/ConfigurationException.h>
#include <boost/regex.hpp>
namespace clcsim
{
ConnectionHandler::
ConnectionHandler()
{
}
ConnectionHandler::
~ConnectionHandler()
{
std::cout << "Destructing conn handler" << std::endl;
}
void
ConnectionHandler::
read_connection_list(
const bool is_white_list,
const std::vector<std::string> &from_radios,
const std::vector<std::string> &to_radios)
{
std::cout << "Reading the connection list" << std::endl;
// Make sure the size of both the input vectors are the same
std::size_t from_radio_size = from_radios.size();
std::size_t to_radio_size = to_radios.size();
if (from_radio_size != to_radio_size)
{
throw ofs::ConfigurationException("Error while initializing the "
"Network model: "
"Connections in from/to lists don't align"
);
}
// Create a regular expression/replacement to find all characters in a non-regular expression
// that would be interpreted as special characters in a regular expression. Replace them with
// escape characters
const boost::regex esc("[.$|()\\[\\]{}*+?\\\\]");
const std::string rep("\\\\&");
// Iterate through the specified connections
for (int i = 0; i < from_radio_size; ++i)
{
std::string from_string = boost::regex_replace(from_radios[i], esc, rep, boost::match_default | boost::format_sed);
std::string to_string = boost::regex_replace(to_radios[i], esc, rep, boost::match_default | boost::format_sed);
//std::cout << "From " << from_string << " to " << to_string << std::endl;
filter_[from_string].insert(to_string);
//filter_[from_radios.at(i)].insert(to_radios.at(i));
}
std::cout << "Got here" << std::endl;
}
} // namespace clcsim
Sorry for so much code.
I saw some similar threads related to segfaults with boost::regex. In those examples, the users had really simple code that just created a regex and matched it and ran into an error. It turned out the issue was related to the Boost versioning. I tried to see if I could replicate those sorts of errors, but those simple examples worked just fine for me. So... I'm pretty stumped. I'd really appreciate any help!

Answer 1

For the sake of removing this from the "Unanswered" list, I'm going to post the answer that was provided in the comments instead of here. The OP determined that the suggestion that Boost linked against eglibc was indeed conflicting with the rest of the code linked against glibc. As such, the OP found that upgrading his OS so that eglibc linked libraries were no longer in use fixed the problem.