打印给定路径中的所有文件和子目录

Question

So, im writing a program to recursively print the directories/sub-directories and files in a given path. im able to go in the first sub-directory and print all the files in it. my problem right now is i need find a way to step back one directory level and continue from where i left off reading. Until the condition occurs at the original directory level.

#include "Everything.h"
#include "Strsafe.h"

WIN32_FIND_DATA ffd;
HANDLE          hFind = INVALID_HANDLE_VALUE;
LARGE_INTEGER   fileSize;
DWORD           dwError;

void showdir(TCHAR *szDir);

int _tmain(int argc, LPCTSTR argv[])
{


    TCHAR           szDir[MAX_PATH];
    size_t          lengthOfArg;

    // verify number of parameters
    if (argc != 2)
    {
        ReportError(_T("Error: Incorrect number of arguments"), 1, FALSE);
    }

    // get the length of the entered directory
    StringCchLength(argv[1], MAX_PATH, &lengthOfArg);

    // verify that the directory path is not too long
    if (lengthOfArg > MAX_PATH - 2)
    {
        ReportError(_T("Error: Directory too long"), 2, FALSE);
    }

    // attach an asterisk (wildcard search char) to end of directory path
    StringCchCopy(szDir, MAX_PATH, argv[1]);
    StringCchCat(szDir, MAX_PATH, _T("*"));

    showdir(szDir);
}

void showdir(TCHAR *szDir)
{
    // begin the search; find the first file in the directory
    hFind = FindFirstFile(szDir, &ffd);
    if (hFind == INVALID_HANDLE_VALUE)
    {
        ReportError(_T("Error in searching"), 3, TRUE);
    }

    //hFind = FindFirstFile(szDir, &ffd);
    while (FindNextFile(hFind, &ffd) != 0)
    {
        if ((ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) == 0)
        {
            fileSize.LowPart = ffd.nFileSizeLow;
            fileSize.HighPart = ffd.nFileSizeHigh;
            _tprintf(_T("%s   %ld\n"), ffd.cFileName, fileSize.QuadPart);

        }       

        // did we find a directory?
        // ffd.dwFileAttributes says this is a directory (FILE_ATTRIBUTE_DIRECTORY)

        if ((ffd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) 
            && (_tcscmp(ffd.cFileName, _T(".")) != 0 && (_tcscmp(ffd.cFileName, _T("..")) != 0)))
        {
            TCHAR fullpath[MAX_PATH];

            StringCchCopy(fullpath, strlen(szDir) - 0, szDir);
            StringCchCat(fullpath, MAX_PATH, ffd.cFileName);
            StringCchCat(fullpath, MAX_PATH, "\\");
            _tprintf(_T("<DIR>  %s \n"), fullpath);
            StringCchCat(fullpath, MAX_PATH, _T("*"));



            showdir(fullpath);

        }   
        // continue the search; try to find more files
    } 

    // figure out if we encountered an error other than "no more files"
    dwError = GetLastError();

    if (dwError != ERROR_NO_MORE_FILES)
    {
        ReportError(_T("Error in searching"), 4, TRUE);
    }

    FindClose(hFind);

}

Answer 1

Your global variables

WIN32_FIND_DATA ffd;
HANDLE          hFind = INVALID_HANDLE_VALUE;
LARGE_INTEGER   fileSize;
DWORD           dwError;

should all be local variables of showdir() . Then each recursion level has its own search handle, and when a nested showdir() returns, the calling showdir() can simply continue enumerating its directory.

Note also that your code ignores the first file in each directory (the result of FindFirstFile() ). You could it rewrite as (error checking omitted for brevity):

hFind = FindFirstFile(szDir, &ffd);
do {

    // ... handle ffd ...

} while (FindNextFile(hFind, &ffd))