This code identifies and monitors removable drives connected to a...

September 2, 2025 at 04:17 AM

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

const std::string INC_FILE = "Storage Edits\\drive.inc";

// Helper: get all removable drives
std::vector<std::pair<std::string, std::string>> GetRemovableDrives() {
    std::vector<std::pair<std::string, std::string>> drives;
    DWORD mask = GetLogicalDrives();
    for (char letter = 'A'; letter <= 'Z'; ++letter) {
        if (mask & 1) {
            std::string root = std::string(1, letter) + ":\\";
            UINT type = GetDriveTypeA(root.c_str());
            if (type == DRIVE_REMOVABLE) {
                char volName[MAX_PATH] = {0};
                if (GetVolumeInformationA(root.c_str(), volName, MAX_PATH, nullptr, nullptr, nullptr, nullptr, 0)) {
                    std::string name = volName[0] ? volName : "USBDrive";
                    std::replace(name.begin(), name.end(), ' ', '_'); // replace spaces
                    drives.push_back({name, std::string(1, letter) + ":"});
                }
            }
        }
        mask >>= 1;
    }
    return drives;
}

// Write INC file
void WriteDriveINC(const std::vector<std::pair<std::string, std::string>>& drives) {
    std::ofstream file(INC_FILE, std::ios::trunc);
    file << "[Variables]\n";
    for (auto& [name, letter] : drives) {
        file << name << "=" << letter << "\n";
    }
    file.close();
}

// Window procedure for device change events
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    if (msg == WM_DEVICECHANGE) {
        if (wParam == DBT_DEVICEARRIVAL || wParam == DBT_DEVICEREMOVECOMPLETE) {
            auto drives = GetRemovableDrives();
            WriteDriveINC(drives);
        }
    }
    return DefWindowProc(hwnd, msg, wParam, lParam);
}

int main() {
    // Ensure folder exists
    CreateDirectoryA("Storage Edits", NULL);

    // Initial write
    WriteDriveINC(GetRemovableDrives());

    // Create a hidden window to receive device notifications
    WNDCLASSA wc = {};
    wc.lpfnWndProc = WndProc;
    wc.lpszClassName = "DriveListenerWindow";
    RegisterClassA(&wc);

    HWND hwnd = CreateWindowA("DriveListenerWindow", "DriveListener", 0, 0, 0, 0, 0, NULL, NULL, NULL, NULL);

    MSG msg;
    while (GetMessageA(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessageA(&msg);
    }

    return 0;
}

This code identifies and monitors removable drives connected to a Windows system and writes their information into a configuration .inc file. Here's a breakdown of what it does:

1. Header Files

It includes various headers for Windows API and standard utilities:

windows.h, fileapi.h: For interacting with Windows functionality like drive information and handling messages.
iostream, fstream, etc.: For input/output and string manipulation.

2. Constants

Defines INC_FILE as the path and name for the output configuration file where removable drive data will be stored: Storage Edits\drive.inc.

3. `GetRemovableDrives` Function

This function detects all removable drives currently connected to the system.
It uses the GetLogicalDrives function to get a bitmask of available drives (A: to Z:), checks whether each one is removable using GetDriveTypeA, and retrieves its volume label using GetVolumeInformationA.
Any spaces in the volume name are replaced with underscores.
The result is a list (std::vector) of pairs containing the volume name and drive letter (e.g., {"MyUSBDrive", "E:"}).

4. `WriteDriveINC` Function

Writes the list of removable drives to the drive.inc file.

The format of the file is:

[Variables]
DriveName1=DriveLetter1
DriveName2=DriveLetter2

Any previous contents of the file are replaced (std::ios::trunc mode).

5. `WndProc` Function

This is a callback function (window procedure) used to handle Windows system messages.
It monitors device changes using the WM_DEVICECHANGE message. Specifically:
- When a device is added (DBT_DEVICEARRIVAL) or removed (DBT_DEVICEREMOVECOMPLETE), the program updates the drive.inc file by calling GetRemovableDrives and writing the new list of drives using WriteDriveINC.

6. `main` Function

The main function does the following:

Ensures the output folder (Storage Edits) exists by calling CreateDirectoryA.
Writes the initial list of removable drives to the drive.inc file using WriteDriveINC.
Creates a hidden window to receive system messages, specifically those for detecting device changes:
- A custom window class is registered using RegisterClassA, and a window is created with CreateWindowA. The window does not display anything on the screen but allows the program to receive system device notifications.
Runs an infinite message-processing loop (GetMessageA) to handle Windows events, ensuring the program updates the drive.inc file when changes (like USB drive insertion/removal) occur.

Purpose

This program continuously monitors removable (e.g., USB) drives. It creates or updates a configuration file (drive.inc) that lists all currently connected removable drives with their names and letters.

The following actions occur:

On startup: Writes the initial list of removable drives to drive.inc.
When USB devices are plugged or unplugged: Detects the change, updates the drive list, and rewrites drive.inc.

Key Features

Dynamic Drive Monitoring: Automatically detects when drives are added or removed.
Outputs Configuration File: Runnable in systems where a consumable .inc file with settings (e.g., drive names and letters) is needed.
Hidden Execution: The program runs silently, interacting with the system without additional user interface.

Use Case

This code could be useful in scenarios where a program or system component requires real-time information about connected USB drives, such as:

Synchronizing files to/from specific drives.
Logging drive usage.
Using removable drives for device authentication or configuration.

Example `drive.inc` Output

After detecting a USB drive named "MY_USB" assigned to drive "E:", the drive.inc file may look like this:

[Variables]
MY_USB=E:

If another drive is plugged in, such as "AnotherDrive" at "F:", it is updated to:

[Variables]
MY_USB=E:
AnotherDrive=F:

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This code identifies and monitors removable drives connected to a...

1. Header Files

2. Constants

3. GetRemovableDrives Function

4. WriteDriveINC Function

5. WndProc Function

6. main Function