Thread: FindFirstFile() Always Returns INVALID_HANDLE_VALUE

I'm trying to create a console application that reads all files in a directory, and count the total line count in it with FindFirstFile() but it always returns an INVALID_HANDLE_VALUE.
Can someone help me to solve this problem?

Code:

#include <iostream>
#include <string>
#include <fstream>
#include <vector>
#include <windows.h> 

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#define NUM_EXTENSIONS 7

const char *Extensions[NUM_EXTENSIONS] = 
{
	"\\*.c", "\\*.h", "\\*.cpp", "\\*.cc", "\\*.cxx", "\\*.hh", "\\*.hpp"
};

int main(int argc, char *argv[])
{
        HANDLE hFind;
	int ErrorCode;
        WIN32_FIND_DATA FindData;
	std::vector<std::string> FileList;
	
	std::cout << "Source Code Line Counter For C/C++\n";

	int FileCount = 0;
	for(unsigned i = 0;i < NUM_EXTENSIONS;++i)
	{
		hFind = FindFirstFile(Extensions[i], &FindData);

Do you have many source code files in your c:\ root directory? (I put a .c file in there, just to test, and sure enough now I only get six invalid handles.)

Well, not many only about 6 .cpp files, but if I change Extension[0] to \\*.cpp, it still returns an INVALID_HANDLE_VALUE.

Let me show what I did so that I could actually compile what you posted (since who knows what's in your for loop):

Code:

#include <stdio.h>
#include <windows.h>

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#define NUM_EXTENSIONS 7

const char *Extensions[NUM_EXTENSIONS] =
{
	"\\*.c", "\\*.h", "\\*.cpp", "\\*.cc", "\\*.cxx", "\\*.hh", "\\*.hpp"
};

int main(int argc, char *argv[])
{
    HANDLE hFind;
    int ErrorCode;
    WIN32_FIND_DATA FindData;

	printf("Source Code Line Counter For C/C++\n");

	int FileCount = 0;
	for(unsigned i = 0;i < NUM_EXTENSIONS;++i)
	{
		hFind = FindFirstFile(Extensions[i], &FindData);
		if (hFind == INVALID_HANDLE_VALUE) {
		    printf("Invalid handle for %s.\n", Extensions[i]);
		}
	}
	return 0;
}

My root directory has (now, just for you) a .cpp file, but none of the others. I get six lines printed -- one for each extension other than .cpp. Does that work for you?

What is the value of GetLastError() after you get an INVALID_HANDLE_VALUE where you know there's a file with that extension?

To be honest, you are not correctly using the handles anyway. You need to use FindClose() when a valid one is found (which you never really check if that occurs). Also,

Code:

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

should occur prior to including windows.h. And no, this isn't effecting your code nor is it related to your bug. You are just misusing WIN32_LEAN_AND_MEAN.

Well, I got seven lines.
I have a .cpp file in my project folder of course.
If I put a .cpp file in D: and changed Extension[0] to "D:\\*.cpp", then it works.
I really don't know what's wrong with this, I tried to debug and hFind is always 0xfffffff.

Btw, GetLastError() returns 2.

Here's the actual code:

Code:

for(unsigned i = 0;i < NUM_EXTENSIONS;++i)
	{
		hFind = FindFirstFile(Extensions[i], &FindData);

		if(hFind != INVALID_HANDLE_VALUE)
		{
			do
			{
				std::string newString = FindData.cFileName;
				int Position = newString.find( Extensions[i] + 3 );
				if( Position != std::string::npos && newString.length() - 3 >= Position)
					FileList.push_back(newString);
			}
			while(FindNextFile(hFind, &FindData));
			int ErrorCode;

			if((ErrorCode = GetLastError()) != ERROR_NO_MORE_FILES)
			{
				std::cout << "Error when looking for files.\nError Code: " << ErrorCode << "\n";
				FileList.clear();
				return 0;
			}

			if (!FindClose(hFind))
			{
				ErrorCode = GetLastError();
				std::cout << "FindClose() returned error code " << ErrorCode << std::endl;
				FileList.clear();
				return 0;
			}
		}
	}

And, how do I use WIN32_LEAN_AND_MEAN correctly?

Originally Posted by ThLstN

Well, I got seven lines.
I have a .cpp file in my project folder of course.

What does your project folder have to do with anything? Your program is looking in C:\, not in your project folder.

Oh is it looking in C: ?
Sorry, I didn't know that, I thought it was a relative path.
So, how can I use a relative path?

Originally Posted by ThLstN

Oh is it looking in C: ?
Sorry, I didn't know that, I thought it was a relative path.
So, how can I use a relative path?

\*.cpp is an absolute path -- to the root directory (\), and then *.cpp there.
If you don't want an absolute path, don't use \.

Oh thanks, I didn't know that!
Edit: Now it's working