fix: tor: Call event_base_loopbreak from the event's callback

src/torcontrol.cpp

@@ -78,7 +78,7 @@ class TorControlConnection
 
     /** Create a new TorControlConnection.
      */
-    TorControlConnection(struct event_base *base);
+    explicit TorControlConnection(struct event_base *base);
     ~TorControlConnection();
 
     /**
@@ -93,7 +93,7 @@ class TorControlConnection
     /**
      * Disconnect from Tor control port.
      */
-    bool Disconnect();
+    void Disconnect();
 
     /** Send a command, register a handler for the reply.
      * A trailing CRLF is automatically added.
@@ -123,7 +123,7 @@ class TorControlConnection
 };
 
 TorControlConnection::TorControlConnection(struct event_base *_base):
-    base(_base), b_conn(0)
+    base(_base), b_conn(nullptr)
 {
 }
 
@@ -140,8 +140,8 @@ void TorControlConnection::readcb(struct bufferevent *bev, void *ctx)
     size_t n_read_out = 0;
     char *line;
     assert(input);
-    //  If there is not a whole line to read, evbuffer_readln returns NULL
-    while((line = evbuffer_readln(input, &n_read_out, EVBUFFER_EOL_CRLF)) != NULL)
+    //  If there is not a whole line to read, evbuffer_readln returns nullptr
+    while((line = evbuffer_readln(input, &n_read_out, EVBUFFER_EOL_CRLF)) != nullptr)
     {
         std::string s(line, n_read_out);
         free(line);
@@ -212,7 +212,7 @@ bool TorControlConnection::Connect(const std::string &target, const ConnectionCB
     b_conn = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE);
     if (!b_conn)
         return false;
-    bufferevent_setcb(b_conn, TorControlConnection::readcb, NULL, TorControlConnection::eventcb, this);
+    bufferevent_setcb(b_conn, TorControlConnection::readcb, nullptr, TorControlConnection::eventcb, this);
     bufferevent_enable(b_conn, EV_READ|EV_WRITE);
     this->connected = _connected;
     this->disconnected = _disconnected;
@@ -225,12 +225,11 @@ bool TorControlConnection::Connect(const std::string &target, const ConnectionCB
     return true;
 }
 
-bool TorControlConnection::Disconnect()
+void TorControlConnection::Disconnect()
 {
     if (b_conn)
         bufferevent_free(b_conn);
-    b_conn = 0;
-    return true;
+    b_conn = nullptr;
 }
 
 bool TorControlConnection::Command(const std::string &cmd, const ReplyHandlerCB& reply_handler)
@@ -335,7 +334,7 @@ static std::map<std::string,std::string> ParseTorReplyMapping(const std::string
                         if (j == 3 && value[i] > '3') {
                             j--;
                         }
-                        escaped_value.push_back(strtol(value.substr(i, j).c_str(), NULL, 8));
+                        escaped_value.push_back(strtol(value.substr(i, j).c_str(), nullptr, 8));
                         // Account for automatic incrementing at loop end
                         i += j - 1;
                     } else {
@@ -369,7 +368,7 @@ static std::map<std::string,std::string> ParseTorReplyMapping(const std::string
 static std::pair<bool,std::string> ReadBinaryFile(const fs::path &filename, size_t maxsize=std::numeric_limits<size_t>::max())
 {
     FILE *f = fsbridge::fopen(filename, "rb");
-    if (f == NULL)
+    if (f == nullptr)
         return std::make_pair(false,"");
     std::string retval;
     char buffer[128];
@@ -395,7 +394,7 @@ static std::pair<bool,std::string> ReadBinaryFile(const fs::path &filename, size
 static bool WriteBinaryFile(const fs::path &filename, const std::string &data)
 {
     FILE *f = fsbridge::fopen(filename, "wb");
-    if (f == NULL)
+    if (f == nullptr)
         return false;
     if (fwrite(data.data(), 1, data.size(), f) != data.size()) {
         fclose(f);
@@ -408,15 +407,15 @@ static bool WriteBinaryFile(const fs::path &filename, const std::string &data)
 /****** Bitcoin specific TorController implementation ********/
 
 /** Controller that connects to Tor control socket, authenticate, then create
- * and maintain a ephemeral hidden service.
+ * and maintain an ephemeral onion service.
  */
 class TorController
 {
 public:
     TorController(struct event_base* base, const std::string& target);
     ~TorController();
 
-    /** Get name fo file to store private key in */
+    /** Get name of file to store private key in */
     fs::path GetPrivateKeyFile();
 
     /** Reconnect, after getting disconnected */
@@ -478,7 +477,7 @@ TorController::~TorController()
 {
     if (reconnect_ev) {
         event_free(reconnect_ev);
-        reconnect_ev = 0;
+        reconnect_ev = nullptr;
     }
     if (service.IsValid()) {
         RemoveLocal(service);
@@ -763,7 +762,9 @@ void InterruptTorControl()
 {
     if (gBase) {
         LogPrintf("tor: Thread interrupt\n");
-        event_base_loopbreak(gBase);
+        event_base_once(gBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
+            event_base_loopbreak(gBase);
+        }, nullptr, nullptr);
     }
 }