From 9050a84670a8b06b62fdd0e54c1f5b6a39541a0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Geoffrey=20=E2=80=9CFrogeye=E2=80=9D=20Preud=27homme?=
 <geoffrey@frogeye.fr>
Date: Fri, 13 Dec 2019 12:35:05 +0100
Subject: [PATCH] Read-only mode

---
 database.py   | 18 ++++++++++++------
 feed_dns.py   |  2 +-
 feed_rules.py |  2 +-
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/database.py b/database.py
index aa38604..d336eba 100755
--- a/database.py
+++ b/database.py
@@ -12,7 +12,6 @@ import logging
 import argparse
 import coloredlogs
 import ipaddress
-import ctypes
 
 coloredlogs.install(
     level='DEBUG',
@@ -27,7 +26,9 @@ class Database():
     PATH = "blocking.db"
 
     def open(self) -> None:
-        self.conn = sqlite3.connect(self.PATH)
+        mode = 'rwc' if self.write else 'ro'
+        uri = f'file:{self.PATH}?mode={mode}'
+        self.conn = sqlite3.connect(uri, uri=True)
         self.cursor = self.conn.cursor()
         self.execute("PRAGMA foreign_keys = ON")
         # self.conn.create_function("prepare_ip4address", 1,
@@ -40,6 +41,8 @@ class Database():
     def execute(self, cmd: str, args: typing.Union[
             typing.Tuple[DbValue, ...],
             typing.Dict[str, DbValue]] = None) -> None:
+        # self.log.debug(cmd)
+        # self.log.debug(args)
         self.cursor.execute(cmd, args or tuple())
 
     def get_meta(self, key: str) -> typing.Optional[int]:
@@ -65,8 +68,11 @@ class Database():
         self.profile()
 
     def initialize(self) -> None:
-        self.enter_step('initialize')
         self.close()
+        self.enter_step('initialize')
+        if not self.write:
+            self.log.error("Cannot initialize in read-only mode.")
+            raise
         os.unlink(self.PATH)
         self.open()
         self.log.info("Creating database version %d.", self.VERSION)
@@ -75,13 +81,13 @@ class Database():
         self.set_meta('version', self.VERSION)
         self.conn.commit()
 
-    def __init__(self) -> None:
+    def __init__(self, write: bool = False) -> None:
         self.log = logging.getLogger('db')
         self.time_last = time.perf_counter()
         self.time_step = 'init'
         self.time_dict: typing.Dict[str, float] = dict()
         self.step_dict: typing.Dict[str, int] = dict()
-        self.accel_ip4_buf = ctypes.create_unicode_buffer('Z'*32, 32)
+        self.write = write
 
         self.open()
         version = self.get_meta('version')
@@ -440,7 +446,7 @@ if __name__ == '__main__':
         help="Update the reference count")
     args = parser.parse_args()
 
-    DB = Database()
+    DB = Database(write=True)
 
     if args.initialize:
         DB.initialize()
diff --git a/feed_dns.py b/feed_dns.py
index f46d97b..2993d6d 100755
--- a/feed_dns.py
+++ b/feed_dns.py
@@ -17,7 +17,7 @@ if __name__ == '__main__':
         help="TODO")
     args = parser.parse_args()
 
-    DB = database.Database()
+    DB = database.Database(write=True)
 
     try:
         DB.enter_step('iowait')
diff --git a/feed_rules.py b/feed_rules.py
index a1d236d..72888f5 100755
--- a/feed_rules.py
+++ b/feed_rules.py
@@ -27,7 +27,7 @@ if __name__ == '__main__':
         help="The input only comes from verified first-party sources")
     args = parser.parse_args()
 
-    DB = database.Database()
+    DB = database.Database(write=True)
 
     fun = FUNCTION_MAP[args.type]