Parsing set of Json files one by one - c++

Question

I am trying to parse Json files using JsonCpp library. but I am facing a problem Which I can not fix it. the code shown below is working perfectly when I am parsing one file but when I added the part which iterates over files in directory the program crashes.
The first function is used to search in a certain directory for Json files and save their names in vector of string (results).
In main function, the program starts by defining the extension required (.json) then calling search function. after that I tried to open each file to parse it.
Finally, Thanks and I really appreciate any kind of help.
#include "jsoncpp.cpp"
#include <stdio.h>
#include "json.h"
#include <iostream>
#include <fstream>
#include <string>
#include <cstdio>
#include <cstring>
#include <unistd.h>
#include <dirent.h>
#include <vector>
using namespace std;
vector<string> results; // holds search results
// recursive search algorithm
void search(string curr_directory, string extension){
DIR* dir_point = opendir(curr_directory.c_str());
dirent* entry = readdir(dir_point);
while (entry){ // if !entry then end of directory
if (entry->d_type == DT_DIR){ // if entry is a directory
string fname = entry->d_name;
if (fname != "." && fname != "..")
search(entry->d_name, extension); // search through it
}
else if (entry->d_type == DT_REG){ // if entry is a regular file
string fname = entry->d_name; // filename
// if filename's last characters are extension
if (fname.find(extension, (fname.length() - extension.length())) != string::npos)
results.push_back(fname); // add filename to results vector
}
entry = readdir(dir_point);
}
return;
}
//
//
//
//
int main(int argc, char *argv[])
{
// read Files list
string extension; // type of file to search for
extension = "json";
// setup search parameters
string curr_directory = "/Users/ITSGC_Ready2Go/3dMap";
search(curr_directory, extension);
// loop over files
//if (results.size()){
//std::cout << results.size() << " files were found:" << std::endl;
for (unsigned int z = 0; z < results.size(); ++z){ // used unsigned to appease compiler warnings
// Opening the file using ifstream function from fstream library
cout <<results[z].c_str()<<endl;
Json::Value obj;
Json::Reader reader;
ifstream test(results[z].c_str());
//test.open (results[z].c_str(), std::fstream::in );
// Selection objects inside the file
reader.parse(test,obj);
//test >> obj;
// Parsing ID object and returning its value as integer
// cout << "id :" << stoi(obj["id"].asString()) <<endl;
// Parsing Line object with its internal objects
const Json::Value& lines = obj["lines"];
for (int i=0; i<lines.size();i++){
cout << "index : " << i << endl;
cout << "id:" << lines[i]["id"].asString() <<endl;
cout << "type:" << lines[i]["type"].asString() <<endl;
cout << "function:" << lines[i]["function"].asString() <<endl;
cout << "color:" << lines[i]["color"].asString() <<endl;
const Json::Value& poly = lines[i]["polyPoints"];
for (int j=0; j<poly.size();j++){
cout << "batch#"<<j<<endl;
cout << "latitude" << poly[j]["latitude"].asFloat()<<endl;
cout << "longitude" << poly[j]["longitude"].asFloat()<<endl;
cout << "altitude" << poly[j]["altitude"].asFloat()<<endl;
}
}
// Reading the OccupancyGrid object
// OccupancyGrid object is copied into constant to parse the arrays inside
const Json::Value& occupancyGrid = obj["occupancyGrid"];
cout << occupancyGrid.size() <<endl;
// The size of occupancyGrid is the used as number of iterations (#of rows)
for (int l=0; l<occupancyGrid.size();l++){
// Arrays inside occupancyGrid are copied into constant to parse the elements inside each array
const Json::Value& element = occupancyGrid[l];
// iterations over the size of the array in order to parse every element
cout << "row" << l << "--> ";
for (int k=0;k<element.size();k++){
cout << element[k].asFloat();
if(k<element.size()-1){ cout<< ",";}
}
cout << endl;
}
// Parsing roadSigns object as found in the file
// Need to understand the difference between format in the mail and the 1456 file
const Json::Value& roadsigns = obj["roadSigns"];
cout << "ArrayType: " << roadsigns["_ArrayType_"].asString()<<endl;
const Json::Value& ArraySize = roadsigns["_ArraySize_"];
for(int t=0;t<ArraySize.size();t++){
cout << ArraySize[t].asInt();
if (t<ArraySize.size()-1){ cout << " , ";}
}
cout<< endl;
if (roadsigns["_ArrayData_"].asString().empty()) {
cout << "ArrayData: "<<roadsigns["_ArrayData_"].asFloat(); }
else { cout << "ArrayData: empty "; }
cout <<endl;
test.close();
test.clear();
cout << "Done" << endl;
cout << "...." << endl;
cout << "...." << endl;
}
//else{
// std::cout << "No files ending in '" << extension << "' were found." << std::endl;
//}
}

Answer 1

Without access to the JSON library I can't help you too much, but the first obvious place for potential crashes would be if (fname.find(extension, (fname.length() - extension.length())) != string::npos). You need to make sure that your file name is longer than the size of your extension before making that call.
Also, for extremely deep directory trees you should put a limit on recursion, and all OSes I know of have some sort of character limit on directory and file names.