1 files changed, 43 insertions, 9 deletions

diff --git a/src/httpserver.cpp b/src/httpserver.cpp
index 720f5c9353..4f8a2b4d8d 100644
--- a/src/httpserver.cpp
+++ b/src/httpserver.cpp
@@ -9,7 +9,9 @@
 #include <httpserver.h>
 
 #include <chainparamsbase.h>
+#include <common/args.h>
 #include <compat/compat.h>
+#include <logging.h>
 #include <netbase.h>
 #include <node/interface_ui.h>
 #include <rpc/protocol.h> // For HTTP status codes
@@ -17,16 +19,17 @@
 #include <sync.h>
 #include <util/strencodings.h>
 #include <util/syscall_sandbox.h>
-#include <util/system.h>
 #include <util/threadnames.h>
 #include <util/translation.h>
 
+#include <condition_variable>
 #include <cstdio>
 #include <cstdlib>
 #include <deque>
 #include <memory>
 #include <optional>
 #include <string>
+#include <unordered_set>
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -34,6 +37,7 @@
 #include <event2/buffer.h>
 #include <event2/bufferevent.h>
 #include <event2/http.h>
+#include <event2/http_struct.h>
 #include <event2/keyvalq_struct.h>
 #include <event2/thread.h>
 #include <event2/util.h>
@@ -146,6 +150,10 @@ static GlobalMutex g_httppathhandlers_mutex;
 static std::vector<HTTPPathHandler> pathHandlers GUARDED_BY(g_httppathhandlers_mutex);
 //! Bound listening sockets
 static std::vector<evhttp_bound_socket *> boundSockets;
+//! Track active requests
+static GlobalMutex g_requests_mutex;
+static std::condition_variable g_requests_cv;
+static std::unordered_set<evhttp_request*> g_requests GUARDED_BY(g_requests_mutex);
 
 /** Check if a network address is allowed to access the HTTP server */
 static bool ClientAllowed(const CNetAddr& netaddr)
@@ -207,6 +215,17 @@ std::string RequestMethodString(HTTPRequest::RequestMethod m)
 /** HTTP request callback */
 static void http_request_cb(struct evhttp_request* req, void* arg)
 {
+    // Track requests and notify when a request is completed.
+    {
+        WITH_LOCK(g_requests_mutex, g_requests.insert(req));
+        g_requests_cv.notify_all();
+        evhttp_request_set_on_complete_cb(req, [](struct evhttp_request* req, void*) {
+            auto n{WITH_LOCK(g_requests_mutex, return g_requests.erase(req))};
+            assert(n == 1);
+            g_requests_cv.notify_all();
+        }, nullptr);
+    }
+
     // Disable reading to work around a libevent bug, fixed in 2.2.0.
     if (event_get_version_number() >= 0x02010600 && event_get_version_number() < 0x02020001) {
         evhttp_connection* conn = evhttp_request_get_connection(req);
@@ -222,7 +241,7 @@ static void http_request_cb(struct evhttp_request* req, void* arg)
     // Early address-based allow check
     if (!ClientAllowed(hreq->GetPeer())) {
         LogPrint(BCLog::HTTP, "HTTP request from %s rejected: Client network is not allowed RPC access\n",
-                 hreq->GetPeer().ToString());
+                 hreq->GetPeer().ToStringAddrPort());
         hreq->WriteReply(HTTP_FORBIDDEN);
         return;
     }
@@ -230,13 +249,13 @@ static void http_request_cb(struct evhttp_request* req, void* arg)
     // Early reject unknown HTTP methods
     if (hreq->GetRequestMethod() == HTTPRequest::UNKNOWN) {
         LogPrint(BCLog::HTTP, "HTTP request from %s rejected: Unknown HTTP request method\n",
-                 hreq->GetPeer().ToString());
+                 hreq->GetPeer().ToStringAddrPort());
         hreq->WriteReply(HTTP_BAD_METHOD);
         return;
     }
 
     LogPrint(BCLog::HTTP, "Received a %s request for %s from %s\n",
-             RequestMethodString(hreq->GetRequestMethod()), SanitizeString(hreq->GetURI(), SAFE_CHARS_URI).substr(0, 100), hreq->GetPeer().ToString());
+             RequestMethodString(hreq->GetRequestMethod()), SanitizeString(hreq->GetURI(), SAFE_CHARS_URI).substr(0, 100), hreq->GetPeer().ToStringAddrPort());
 
     // Find registered handler for prefix
     std::string strURI = hreq->GetURI();
@@ -458,15 +477,27 @@ void StopHTTPServer()
         evhttp_del_accept_socket(eventHTTP, socket);
     }
     boundSockets.clear();
-    if (eventBase) {
-        LogPrint(BCLog::HTTP, "Waiting for HTTP event thread to exit\n");
-        if (g_thread_http.joinable()) g_thread_http.join();
+    {
+        WAIT_LOCK(g_requests_mutex, lock);
+        if (!g_requests.empty()) {
+            LogPrint(BCLog::HTTP, "Waiting for %d requests to stop HTTP server\n", g_requests.size());
+        }
+        g_requests_cv.wait(lock, []() EXCLUSIVE_LOCKS_REQUIRED(g_requests_mutex) {
+            return g_requests.empty();
+        });
     }
     if (eventHTTP) {
-        evhttp_free(eventHTTP);
-        eventHTTP = nullptr;
+        // Schedule a callback to call evhttp_free in the event base thread, so
+        // that evhttp_free does not need to be called again after the handling
+        // of unfinished request connections that follows.
+        event_base_once(eventBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
+            evhttp_free(eventHTTP);
+            eventHTTP = nullptr;
+        }, nullptr, nullptr);
     }
     if (eventBase) {
+        LogPrint(BCLog::HTTP, "Waiting for HTTP event thread to exit\n");
+        if (g_thread_http.joinable()) g_thread_http.join();
         event_base_free(eventBase);
         eventBase = nullptr;
     }
@@ -643,6 +674,9 @@ std::optional<std::string> HTTPRequest::GetQueryParameter(const std::string& key
 std::optional<std::string> GetQueryParameterFromUri(const char* uri, const std::string& key)
 {
     evhttp_uri* uri_parsed{evhttp_uri_parse(uri)};
+    if (!uri_parsed) {
+        throw std::runtime_error("URI parsing failed, it likely contained RFC 3986 invalid characters");
+    }
     const char* query{evhttp_uri_get_query(uri_parsed)};
     std::optional<std::string> result;