Find all files in all directories in c++

Question

I am trying to find all files in all directories, but I don't know how to handle subdirectories. In this code, the code looks trough all subdirs, but I don't know how to jump back. Does anyone know how to do this?

__declspec(dllexport) void GetFiles(char* filedir, char* path)
{
    string s[1000];
    string path2 = path;
    UINT index = 0;

    WIN32_FIND_DATA ffd;
    TCHAR szDir[MAX_PATH];
    HANDLE hFind = INVALID_HANDLE_VALUE;
    DWORD dwError=0;

    StringCchCopy(szDir, MAX_PATH, filedir);

    if (INVALID_HANDLE_VALUE == hFind) 
        return;

    do
    {

        DWORD attributes = ffd.dwFileAttributes;

        if (attributes & FILE_ATTRIBUTE_HIDDEN)
            continue;
        else if (attributes & FILE_ATTRIBUTE_DIRECTORY)
        {
            TCHAR dir2[MAX_PATH];
            path2 = path;
            path2 += ffd.cFileName;
            path2 += "\\*";
            StringCchCopy(dir2, MAX_PATH, path2.c_str());
            SetCurrentDirectory(dir2);
        }
        else
        {
            s[index] = path;
            s[index] += ffd.cFileName;
            index++;
        }
    }
    while (FindNextFile(hFind, &ffd) >= 0); // needs to jump back if zero

    FindClose(hFind);
}

EDIT: functions had the same name which confused the compiler

Answer 1

Doing a bit of searching through old posts, I guess I've mentioned doing a breadth-first search a number of times, but never really posted code to show how to do it. I guess I might as well do that.

#include <windows.h>
#include <queue>
#include <string>
#include <iostream>

// I think MS's names for some things are obnoxious.
const HANDLE HNULL = INVALID_HANDLE_VALUE;
const int A_DIR = FILE_ATTRIBUTE_DIRECTORY;

// We'll process a file by printing its path/name
void process(std::string const &path, WIN32_FIND_DATA const &file) { 
    std::cout << path << file.cFileName << "\n";
}

void find_file(std::string const &folder_name, std::string const &fmask) {
    HANDLE finder;          // for FindFirstFile
    WIN32_FIND_DATA file;   // data about current file.
    std::priority_queue<std::string, std::vector<std::string>,
                       std::greater<std::string> > dirs;
    dirs.push(folder_name); // start with passed directory 

    do {
        std::string path = dirs.top();// retrieve directory to search
        dirs.pop();

        if (path[path.size()-1] != '\\')  // normalize the name.
            path += "\\";

        std::string mask = path + fmask;    // create mask for searching

        // traverse a directory. Search for sub-dirs separately, because we 
        // don't want a mask to apply to directory names. "*.cpp" should find
        // "a\b.cpp", even though "a" doesn't match "*.cpp".
        //
        // First search for files:
        if (HNULL==(finder=FindFirstFile(mask.c_str(), &file))) 
            continue;

        do { 
            if (!(file.dwFileAttributes & A_DIR))
                process(path, file);
        } while (FindNextFile(finder, &file));
        FindClose(finder);

        // Then search for subdirectories:
        if (HNULL==(finder=FindFirstFile((path + "*").c_str(), &file)))
            continue;
        do { 
            if ((file.dwFileAttributes & A_DIR) && (file.cFileName[0] != '.'))
                dirs.push(path + file.cFileName);
        } while (FindNextFile(finder, &file));
        FindClose(finder);
    } while (!dirs.empty());
}

int main(int argc, char **argv) { 
    if (argc > 2)
        find_file(argv[1], argv[2]);
    else
        find_file("C:\\", "*");
    return 0;
}

Answer 2

Instead of changing directory via SetCurrentDirectory() use a recursive call on GetFiles(). This would require that the caller pass in a reference to an array (or std::vector<std::string>) for the list of files to be stored in instead of using the local array s.

Answer 3

Why not use the boost recursive_directory_iterator.

Note: untested (but should look something like this).

namespace bfs = boost::filesystem;

std::vector<std::string>    filenames;

std::copy(bfs::recursive_directory_iterator("<path>"),
          bfs::recursive_directory_iterator(),
          std::back_inserter(filenames)
         );

Answer 4

I'd have a look at the directory iterators of boost instead.

http://www.boost.org/doc/libs/1_51_0/libs/filesystem/doc/index.htm

There are examples covering what you are trying to do, and it will work for almost any OS you can think of.

Have a look at example 3. It shows how to loop over all contents of the directory. If you find a new directory you have not seen before, you just do the same on that. There are tests telling you if the file is regular, directory etc so give it a try.

Answer 5

I think the easiest way to do it is by doing a recursive function.

This would roughly look like something like this in "c" pseudo code

void GetFiles( char*** file_path_table, char* dir )
{
   char **file_paths;
   file_paths = getAllFiles( dir );
   foreach( path in file_paths )
   {
       if ( is_directory( path ) )
       {
           GetFiles( file_path_table, path );
       }
       else
       {
           add_file_to_table( file_path_table, path );
       }
   }
}