feat: test and set map count

dzgui/util/map_count.py

@@ -1,7 +1,20 @@
 import subprocess
+import sys
+import tempfile
 
 from pathlib import Path
 from dzgui.const.constants import VM_FILE, MIN_COUNT
+from dzgui.util.bash import concat_bash_args
+from dzgui.views.dialogs.early_alert import EarlyIgnoreDialog
+
+
+def is_map_count_valid() -> bool:
+    count = get_map_count()
+    if count is None:
+        # NOTE: permit if count was unreadable
+        return True
+    return count >= MIN_COUNT
+
 
 def get_map_count() -> int | None:
     path = Path(VM_FILE)
@@ -10,19 +23,42 @@ def get_map_count() -> int | None:
     count = int(path.read_text())
     return count
 
-    # TODO: unfinished
-    #if count < MIN_COUNT:
-    #    print("needs sudo escalation")
-    #    # pop prompt
-    #    # get response
-    #    set_map_count()
-    #return count
 
-# TODO: unfinished
+def test_map_count() -> None:
+    if is_map_count_valid():
+        return
+    msg = (
+        "System map count is not high enough to run DayZ.\n"
+        "Please exit and run 'dzgui -m' to update map count."
+    )
+    EarlyIgnoreDialog(msg)
+
+
 def set_map_count() -> None:
+    valid = is_map_count_valid()
+    if valid is None:
+        return
+    elif valid:
+        print("System map count already meets the minimum.")
+        return
+
     conf = "/etc/sysctl.d/dayz.conf"
     count = f"vm.max_map_count={MIN_COUNT}"
-    with open(conf, "w") as f:
-        f.write(count)
-    # TODO: use concat_bash_args()
-    subprocess.run(["/usr/bin/sudo", "sysctl", "-p", conf])
+    try:
+        msg = (
+            f"Updated map count will be written to the file '{conf}'.\n"
+            "Enter sudo password to proceed."
+        )
+        print(msg)
+        with tempfile.NamedTemporaryFile(delete=False) as f:
+            tmp = f.name
+        Path(tmp).write_text(count)
+        args = concat_bash_args(f"sudo mv {tmp} {conf}")
+        subprocess.run([*args])
+        args = concat_bash_args(f"sudo sysctl -p {conf}")
+        subprocess.run([*args])
+    except Exception as e:
+        print(e)
+    except KeyboardInterrupt:
+        print("User exit")
+        sys.exit(0)