Find all files in a directory and its subdirectory - c++

Question

I would like to list all files in a given directory and its different subdirectory.
I found some code that I modified but it doing a never ending loop and I don't understand why.
int getdir (string dir, vector<string> &files)
{
DIR *dp;
struct dirent *dirp;
if((dp = opendir(dir.c_str())) == NULL) {
cout << "Error(" << errno << ") opening " << dir << endl;
return errno;
}
while ((dirp = readdir(dp)) != NULL) {
files.push_back(string(dirp->d_name));
string test=dir+"/"+dirp->d_name;
getdir(test,files);
}
closedir(dp);
return 0;
}
My main:
int main()
{
string dir = string(".");
vector<string> files = vector<string>();
getdir(dir,files);
for (unsigned int i = 0;i < files.size();i++) {
cout << files[i] << endl;
}
return 0;
}
How could I fix it?

Answer 1

This is likely due to the "." directory entry returned as the first entry which represents the current directory.
This causes your algorithm to try to list the entries for ./. and then ././. endlessly repeating until your program would eventual crash when it ran out of memory.
There's also a ".." directory entry which represents the parent directory and can cause a similar recursive problem.
As noted by Jerry Coffin, symbolic links can also cause a very similar issue if you have links which point to a directory which is the parent or ancestor of the symbolic link. This could be avoided with a much more complicated check or just simply excluding DT_LNK type entries all together.
Another issue is that you're trying to call getdir on files as well as subdirectories.
Try the following changes
while ((dirp = readdir(dp)) != NULL) {
string name(dir->d_name);
if (name != "." && name != "..") {
string test=dir+"/"+name;
files.push_back(test);
if (dir->d_type == DT_DIR) {
getdir(test,files);
}
}
}