save recursion output to text file - c++

I am trying to recursively list the files in a directory. However when I save the output to a text file, it works, but the file contents keep being reset. So the file size will be 2Kb, and then it is reset to 1Kb, 30Kb reset to 1Kb, and so on. The code is not saving all the output to the text file and only some of the last lines are saved to output.txt.
#include "stdafx.h"
#include <Windows.h>
#include <iostream>
#include <Psapi.h>
#include <fstream>
using namespace std;
void listDir(wchar_t * szCurrentDirectory);
int main()
{
// return current directory where app run
DWORD nBufferLength = MAX_PATH;
wchar_t szCurrentDirectory[MAX_PATH];
GetCurrentDirectory(nBufferLength, szCurrentDirectory);
listDir(szCurrentDirectory);
system("pause");
return 0;
}
void listDir(wchar_t * szCurrentDirectory)
{
wchar_t addPath[MAX_PATH] = L"\\*";
WIN32_FIND_DATA FindFileData;
wchar_t buf[MAX_PATH];
swprintf(buf, MAX_PATH,L"%s%s", szCurrentDirectory, addPath);
HANDLE hFind;
hFind = FindFirstFile(buf, &FindFileData);
wofstream myfile("c:/output.txt");
if (myfile.is_open())
{
if (hFind != INVALID_HANDLE_VALUE)
{
do
{
// Check if is a folder or not.
if (FindFileData.dwFileAttributes != FILE_ATTRIBUTE_REPARSE_POINT)
{
// Ignore current folder and parent folder.
if (wcscmp(FindFileData.cFileName, L".") && wcscmp(FindFileData.cFileName, L"..") != 0)
{
if (wcscmp(FindFileData.cFileName, L"$RECYCLE.BIN") != 0)
{
// return current directory where app run
wchar_t filepath[10000];
// Append slash to current directory.
swprintf(filepath, 10000, L"%s%s%s", szCurrentDirectory, L"\\", FindFileData.cFileName);
// Output the file.
myfile << filepath << endl;
if (FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
{
// Recursive
listDir(filepath);
} // if directory
} // if not recycle bin
} // if not . or ..
} if not reparse point
} while (FindNextFile(hFind, &FindFileData) != 0);
FindClose(hFind);
myfile.close();
}
}
}
try to run the app in c: drive and look the output in output.txt. the output keep reset.

Pass the open file as a parameter instead.
Change
void listDir(wchar_t * szCurrentDirectory)
to
void listDir(wofstream & myfile,wchar_t * szCurrentDirectory)
then remove the file opening code from listDir().
Delete this line:
wofstream myfile("c:/output.txt");
And then call it in main() like this:
wofstream myfile("c:/output.txt");
listDir(myfile,szCurrentDirectory);
And finally in listDir() change
listDir(filepath);
to
listDir(myfile,filepath);

The right answer is definitely to open the file once (in the main program), and then pass the stream into into the listdir function.
However ... there is an alternative. It is not appropriate in this case, it might be in similar cases. You can open the file in append mode, so the contents is never overwritten. You just need to change the line where you open the file to:
std::wofstream myfile("c:/output.txt", std::ios_base::app);
The output will be written to the end of the file, preserving the existing contents.

Open the file in main and pass the handle as a second parameter to the listDir function.
Don't open it in listDir

Related

How to find a list of files in a specific directory without dirent.h or boost [duplicate]

I'm looking to list and store the contents of a directory in a struct using C on Windows.
I'm not necessarily looking for anyone to write out the code I'm looking for, rather point me in the right direction when it comes to which library I should be looking at.
I've been Googling for a few hours now and all I'm finding is C#, C++ solutions so any help would be greatly appreciated.
Just like everyone else said (with FindFirstFile, FindNextFile and FindClose)... but with recursion!
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
bool ListDirectoryContents(const char *sDir)
{
WIN32_FIND_DATA fdFile;
HANDLE hFind = NULL;
char sPath[2048];
//Specify a file mask. *.* = We want everything!
sprintf(sPath, "%s\\*.*", sDir);
if((hFind = FindFirstFile(sPath, &fdFile)) == INVALID_HANDLE_VALUE)
{
printf("Path not found: [%s]\n", sDir);
return false;
}
do
{
//Find first file will always return "."
// and ".." as the first two directories.
if(strcmp(fdFile.cFileName, ".") != 0
&& strcmp(fdFile.cFileName, "..") != 0)
{
//Build up our file path using the passed in
// [sDir] and the file/foldername we just found:
sprintf(sPath, "%s\\%s", sDir, fdFile.cFileName);
//Is the entity a File or Folder?
if(fdFile.dwFileAttributes &FILE_ATTRIBUTE_DIRECTORY)
{
printf("Directory: %s\n", sPath);
ListDirectoryContents(sPath); //Recursion, I love it!
}
else{
printf("File: %s\n", sPath);
}
}
}
while(FindNextFile(hFind, &fdFile)); //Find the next file.
FindClose(hFind); //Always, Always, clean things up!
return true;
}
ListDirectoryContents("C:\\Windows\\");
And now its UNICODE counterpart:
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
bool ListDirectoryContents(const wchar_t *sDir)
{
WIN32_FIND_DATA fdFile;
HANDLE hFind = NULL;
wchar_t sPath[2048];
//Specify a file mask. *.* = We want everything!
wsprintf(sPath, L"%s\\*.*", sDir);
if((hFind = FindFirstFile(sPath, &fdFile)) == INVALID_HANDLE_VALUE)
{
wprintf(L"Path not found: [%s]\n", sDir);
return false;
}
do
{
//Find first file will always return "."
// and ".." as the first two directories.
if(wcscmp(fdFile.cFileName, L".") != 0
&& wcscmp(fdFile.cFileName, L"..") != 0)
{
//Build up our file path using the passed in
// [sDir] and the file/foldername we just found:
wsprintf(sPath, L"%s\\%s", sDir, fdFile.cFileName);
//Is the entity a File or Folder?
if(fdFile.dwFileAttributes &FILE_ATTRIBUTE_DIRECTORY)
{
wprintf(L"Directory: %s\n", sPath);
ListDirectoryContents(sPath); //Recursion, I love it!
}
else{
wprintf(L"File: %s\n", sPath);
}
}
}
while(FindNextFile(hFind, &fdFile)); //Find the next file.
FindClose(hFind); //Always, Always, clean things up!
return true;
}
ListDirectoryContents(L"C:\\Windows\\");
Probably You are looking for these functions: FindFirstFile, FindNextFile, and FindClose.
To list file contents you can search a directory with these APIs: FindFirstFileEx, FindNextFile and FindClose. You'll need to #include <windows.h>, that'll get you access to the Windows API. They're C functions and so compatible with C++. If you want "specifically C++", try searching for listing directories using MFC.

c++ - fopen() internally changes my filename?

I use fopen() in my c++ program and I tried to open a .aff file.
I want to parse a file named car_wheel.aff and after if(ifp=fopen(path,"r")) has executed, it seems the fopen() function changes my path variable???
I add some detail to my question to the comment.
code (since variable path is constructed by my code, I put the whole piece of code here, which may seem a bit redundant.)
char* dir = "../kitchen/";
char filename[100];
char* path;
FILE *ifp;
int detail_level;
if(fscanf(fp,"%d %s",&detail_level,filename)!=2)
{
printf("Error: could not parse include.\n");
exit(0);
}
path = (char*)malloc(strlen(dir)+strlen(filename));
strcpy(path, dir);
strcat(path, filename); // path is "../kitchen/car_wheel.aff"
if(detail_level<=gDetailLevel)
{
if(ifp=fopen(path,"r"))
{
viParseFile(ifp);
fclose(ifp);
}
else
{
// jumped here and path became "../kitchen/car_wheel.aff1\002"
if (ifp == NULL) {
perror(path);
exit(EXIT_FAILURE);
}
printf("Error: could not open include file: <%s>.\n",filename);
exit(1);
}
}
I debugged the code in my ide, and it gave the filename char array is
and there is no '1\002' behind my filename variable. What happened??
The problem is here:
path = (char*)malloc(strlen(dir)+strlen(filename));
You don't allocate space for the terminating zero character. Change it to this:
path = (char*)malloc(strlen(dir)+strlen(filename)+1);

Why Am I Writing 0 bytes with WriteFile?

I'm trying to make a program that finds the next .exe file in a user-defined directory and writes a flag to it (for a computer security class).
It's currently writing 0 bytes, and I'm not sure why.
Here is my code so far:
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <Windows.h>
#include <fstream>
using namespace std;
typedef wchar_t wchar;
struct thePlague{
long int origBytes;
wchar_t flag[6];
};
void main() {
WIN32_FIND_DATA findFileData; //Windows structure that receives info about a found file or directory
HANDLE hFind = INVALID_HANDLE_VALUE; //Handle that holds whether or not a file was successfully found with FindNextFile
LARGE_INTEGER fileSize;
wchar szDir[MAX_PATH];
DWORD dwError = 0;
wchar directory[MAX_PATH];
wcout<<L"Please enter a directory: ";
wcin>>directory;
// Check that the input path plus 7 is not longer than MAX_PATH.
// 7 characters are for the "\*.exe" plus NULL appended below.
if (wcslen(directory) > (MAX_PATH - 7)) {
wcout<<L"\nDirectory is too long\n";
return;
}
wcout<<L"Target directory is: "<<directory<<endl;
// Prepare string for use with FindFile functions. First, copy the
// string to a buffer, then append '\*' to the directory name.
wcscpy(szDir, directory);
wcscat(szDir, L"\\*.exe");
//Find the first file in the directory
hFind = FindFirstFile(szDir, &findFileData);
if (hFind == INVALID_HANDLE_VALUE) {
wcout<<L"FindFirstFile Failed"<<GetLastError()<<endl;
return;
}
do {
fileSize.LowPart = findFileData.nFileSizeLow;
fileSize.HighPart = findFileData.nFileSizeHigh;
wcout<<findFileData.cFileName<<L" "<<fileSize.QuadPart<<L" bytes\n";
DWORD dwBytesWritten = 0; //# of bytes written by WriteFile
wchar_t *buffer = (wchar *)malloc(sizeof(thePlague)); //A buffer the size of our struct (infection flag)
wofstream writeToBuffer(buffer, ios::binary); //Open the buffer for writing
thePlague newVictim; //New infection flag
writeToBuffer.write((const wchar_t*)&newVictim, sizeof(thePlague));
writeToBuffer.close();
DWORD dwErrorFlag;
dwErrorFlag = WriteFile(hFind, //The handle holding the file we are writing to
buffer, //The buffer holding what we want to write to the file, in this case a struct
sizeof(thePlague), //How many bytes to write to the file
&dwBytesWritten, //Where to store the # of bytes successfully written
NULL //Where to write to incase of overlap
);
if (dwErrorFlag == false)
wcout<<L"Error was: "<<GetLastError()<<endl;
wcout<<L"# of bytes written: "<<dwBytesWritten<<endl;
} while(FindNextFile(hFind, &findFileData) != 0);
FindClose(hFind);
return;
}
When I run this, I get:
Please enter a directory: C:\Infect
Target directory is: C:\Infect
hello.exe 65536 bytes
Error was: 6
# of bytes written: 0
Press any key to continue . . .
I know this is an ERROR_INVALID_HANDLE, but how do I fix this?
You need to open the file before writing to it. Your HANDLE hFind is just a handle to iterate over directories/files, not an open handle to a file.
Use CreateFile() to open the file
FindFirstFile returns a search handle, but WriteFile requires an open file handle. Use CreateFile to open the file before writing to it with WriteFile.

Find all files in all directories in c++

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
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 );
}
}
}
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)
);
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.
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.
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;
}

Problems with Visual C++: Reading all files in a directory

I'm trying to read all files in a directory. I have the following code:
void scanDirectory(char* dir)
{
WIN32_FIND_DATA FindFileData;
HANDLE hFind = INVALID_HANDLE_VALUE;
char DirSpec[MAX_PATH]; // directory specification
strcpy(DirSpec, dir);
strcat(DirSpec, "\\*");
hFind = FindFirstFile(DirSpec, &FindFileData);
int i = 0;
do {
i++;
printf("%d \n", i);
if (FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
{
printf(" %s <DIR>\n", FindFileData.cFileName);
}
else
{
printf("File %s\n", FindFileData.cFileName);
}
} while(!FindNextFile(hFind, &FindFileData));
FindClose(hFind);
}
The problem is that when I execute the code it results in an infinite loop. Also the output characters are strange, like "File ".
I think you are not using chars and wide chars in a consequent way. You should either use functions with wide char and wchar_t type or vice versa. (But it was a compile error for me so it may depend on some kind of project settings as well.)
And your exit condition in the while loop is also wrong it should test for FindNextFile and not !FindNextFile. The infinite loop may be because of this condition as if it doesn't find any files it will run forever.
Also you should test for the return value of FindFirstFile and not go into the loop if it doesn't find any files.
You are calling !FindNextFile instead of FindNextFile, also you are not checking why
the FindNextFile fails, so you can't be sure if all the files were processed.
Use something like this.
WIN32_FIND_DATA stFindData;
HANDLE hFind = FindFirstFile(cSearchPattern, &stFindData);
if(hFind != INVALID_HANDLE_VALUE)
{
do
{
// Process File
}
while (FindNextFile(hFind, &stFindData) != 0);
DWORD dwError = GetLastError();
if (dwError != ERROR_NO_MORE_FILES)
{
// Not All Files processed, deal with Error
}
FindClose(hFind);
}
Can't you just use .Net like below:
System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo(Path);
System.IO.FileInfo[] files = dir.GetFiles();
foreach (System.IO.FileInfo file in files)
{
// Do whatever you need with the file info...
string filename = file.Name;
string fullFilename = file.FullName;
}
This is a c# example but you can use for each in C++ the same. Hope this helps.