我在运行一些C++代码时遇到了问题。基本上，它与大多数输入一起正常工作，但对于某些输入，在我的主函数返回后会发生段错误。这一直令人困惑。我停止运行，以获取堆栈跟踪信息，结果显示：
#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
这让我觉得我在使用boost正则表达式时一定出了些问题，但是我想不出来。我的正则表达式使用方式是用户可以输入一堆字符串。这些字符串可能只是普通文本，也可能是正则表达式。因此，我基本上将所有的输入都视为正则表达式进行处理。但是，如果用户提供的字符串旨在作为纯文本，但包含一个可能被解释为正则表达式的特殊字符怎么办？我的做法是遍历所有纯文本输入字符串并转义所有这些字符。
这是我正在处理的代码。这是我的主要操作：
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;
}
这段代码有一个我创建的ConnectionHandler对象。以下是它的头文件：
#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_
以下是来源：
#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
非常抱歉有这么多代码。
我看到了一些与boost::regex相关的类似主题的讨论。在那些例子中，用户只是创建了一个正则表达式并进行匹配，就遇到了错误。结果发现问题与Boost版本相关。我尝试看能否复制那些错误，但是对我来说，那些简单的例子都运行良好。所以...我真的很困惑。我非常感谢任何帮助！