From c0736e8acb40cbe35b82b3e4a9b915d19b015926 Mon Sep 17 00:00:00 2001
From: Ethan Dalool <ethan@voussoir.net>
Date: Thu, 20 Aug 2020 11:39:49 -0700
Subject: [PATCH] Add windrives.py.

---
 voussoirkit/windrives.py | 79 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 voussoirkit/windrives.py

diff --git a/voussoirkit/windrives.py b/voussoirkit/windrives.py
new file mode 100644
index 0000000..e4e41e4
--- /dev/null
+++ b/voussoirkit/windrives.py
@@ -0,0 +1,79 @@
+'''
+NOTE: I have not yet figured out how to get a list of volumes that are mounted
+to folders instead of drive letters. I think this is the API I need:
+https://docs.microsoft.com/en-us/windows/win32/fileio/enumerating-volume-mount-points
+'''
+import ctypes
+import string
+
+def get_drive_info(letter):
+    '''
+    Given a drive letter, return a dictionary containing its attributes.
+
+    Thanks Nicholas Orlowski
+    http://stackoverflow.com/a/12056414
+    '''
+    kernel32 = ctypes.windll.kernel32
+    name_buffer = ctypes.create_unicode_buffer(1024)
+    filesystem_buffer = ctypes.create_unicode_buffer(1024)
+    serial_number = None
+    max_component_length = None
+    file_system_flags = None
+
+    letter = letter.rstrip(':\\/')
+    drive_active = kernel32.GetVolumeInformationW(
+        ctypes.c_wchar_p(f'{letter}:\\'),
+        name_buffer,
+        ctypes.sizeof(name_buffer),
+        serial_number,
+        max_component_length,
+        file_system_flags,
+        filesystem_buffer,
+        ctypes.sizeof(filesystem_buffer),
+    )
+    info = {
+        'active': bool(drive_active),
+        'filesystem': filesystem_buffer.value,
+        'name': name_buffer.value,
+    }
+    return info
+
+def get_drive_letters():
+    '''
+    Return a list of all connected drive letters.
+
+    Thanks RichieHindle
+    http://stackoverflow.com/a/827398
+
+    "If the function succeeds, the return value is a bitmask representing the
+    currently available disk drives. Bit position 0 (the least-significant bit)
+    is drive A, bit position 1 is drive B, bit position 2 is drive C, and so on."
+    https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getlogicaldrives
+    '''
+    letters = []
+    bitmask = ctypes.windll.kernel32.GetLogicalDrives()
+    for letter in string.ascii_uppercase:
+        if bitmask & 1:
+            letters.append(letter)
+        bitmask >>= 1
+    return letters
+
+def get_drive_letter_by_name(name):
+    '''
+    Given the name of a drive (the user-customizable name seen in Explorer),
+    return the letter of that drive.
+
+    Raises KeyError if it is not found.
+    '''
+    drives = get_drive_map()
+    for (letter, info) in drives.items():
+        if info['name'] == name:
+            return letter
+    raise KeyError(name)
+
+def get_drive_map():
+    '''
+    Return a dict of {letter: info}.
+    '''
+    drives = {letter: get_drive_info(letter) for letter in get_drive_letters()}
+    return drives