Fix HTTP connection shutdown issue (#179)

google · May 14, 2018 · c445d4f · c445d4f
1 parent 4e4bfe9
commit c445d4f
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Showing 2 changed files with 53 additions and 12 deletions.
diff --git a/sling/http/http-server.cc b/sling/http/http-server.cc
@@ -329,11 +329,15 @@ void HTTPServer::Worker() {
     // Get new events.
     int rc = epoll_wait(pollfd_, events, max_events, 2000);
     if (stop_) break;
-    if (rc == 0 || errno == EAGAIN) continue;
+    if (errno == EAGAIN) continue;
     if (rc < 0) {
       LOG(ERROR) << Error("epoll_wait");
       break;
     }
+    if (rc == 0) {
+      ShutdownIdleConnections();
+      continue;
+    }
 
     // Process events.
     for (int i = 0; i < rc; ++i) {
@@ -364,14 +368,20 @@ void HTTPServer::Worker() {
             conn->state_ = HTTP_STATE_TERMINATE;
           }
 
-          // Update expected events.
-          ev->events = 0;
-          if (conn->AwaitsInput()) ev->events |= EPOLLIN;
-          if (conn->HasOutput()) ev->events |= EPOLLOUT;
-          rc = epoll_ctl(pollfd_, EPOLL_CTL_MOD, conn->sock_, ev);
-          if (rc < 0) LOG(ERROR) << Error("epoll_ctl");
-          VLOG(5) << "Done processing in state " << conn->state_
-                  << ", events " << ev->events;
+          if (conn->state_ == HTTP_STATE_TERMINATE) {
+            conn->Shutdown();
+            VLOG(5) << "Shutdown HTTP connection";
+          } else {
+            // Update expected events.
+            ev->events = 0;
+            if (conn->AwaitsInput()) ev->events |= EPOLLIN;
+            if (conn->HasOutput()) ev->events |= EPOLLOUT;
+            rc = epoll_ctl(pollfd_, EPOLL_CTL_MOD, conn->sock_, ev);
+            if (rc < 0) LOG(ERROR) << Error("epoll_ctl");
+            conn->last_ = time(0);
+            VLOG(5) << "Done processing in state " << conn->state_
+                    << ", events " << ev->events;
+          }
         }
       }
     }
@@ -437,6 +447,20 @@ void HTTPServer::RemoveConnection(HTTPConnection *conn) {
   conn->next_ = conn->prev_ = nullptr;
 }
 
+void HTTPServer::ShutdownIdleConnections() {
+  if (options_.max_idle <= 0) return;
+  MutexLock lock(&mu_);
+  time_t expire = time(0) - options_.max_idle;
+  HTTPConnection *conn = connections_;
+  while (conn != nullptr) {
+    if (conn->last_ < expire) {
+      conn->Shutdown();
+      VLOG(5) << "Shut down idle connection";
+    }
+    conn = conn->next_;
+  }
+}
+
 HTTPConnection::HTTPConnection(HTTPServer *server, int sock)
     : server_(server), sock_(sock) {
   next_ = prev_ = nullptr;
@@ -446,6 +470,7 @@ HTTPConnection::HTTPConnection(HTTPServer *server, int sock)
   state_ = HTTP_STATE_IDLE;
   header_state_ = HDR_STATE_FIRSTWORD;
   keep_ = false;
+  last_ = time(0);
 }
 
 HTTPConnection::~HTTPConnection() {
@@ -514,10 +539,9 @@ Status HTTPConnection::Process(int events) {
       // Fall through
 
     case HTTP_STATE_READ_BODY:
+      // Check if any input data is ready.
+      if ((events & EPOLLIN) == 0) return Status::OK;
       while (request_body_.size() < request_->content_length()) {
-        // Check if any input data is ready.
-        if ((events & EPOLLIN) == 0) return Status::OK;
-
         // Receive more data.
         Status st = Recv(&request_body_, &done);
         if (!st.ok()) return st;
@@ -656,6 +680,10 @@ Status HTTPConnection::Send(HTTPBuffer *buffer, bool *done) {
   return Status::OK;
 }
 
+void HTTPConnection::Shutdown() {
+  shutdown(sock_, SHUT_RDWR);
+}
+
 void HTTPConnection::Dispatch() {
   // Allocate response object.
   delete response_;

diff --git a/sling/http/http-server.h b/sling/http/http-server.h
@@ -17,6 +17,7 @@
 
 #include <netinet/in.h>
 #include <string.h>
+#include <time.h>
 #include <string>
 
 #include "sling/base/status.h"
@@ -122,6 +123,9 @@ struct HTTPServerOptions {
   // Number of events per worker poll.
   int max_events = 1;
 
+  // Maximum idle time (in seconds) before connection is shut down.
+  int max_idle = 600;
+
   // Initial buffer size.
   int initial_bufsiz = 1 << 10;
 
@@ -192,6 +196,9 @@ class HTTPServer {
   // Remove connection from server.
   void RemoveConnection(HTTPConnection *conn);
 
+  // Shut down idle connections.
+  void ShutdownIdleConnections();
+
   // Server configuration.
   HTTPServerOptions options_;
 
@@ -277,12 +284,18 @@ class HTTPConnection {
   // be sent without blocking has been sent.
   Status Send(HTTPBuffer *buffer, bool *done);
 
+  // Shut down connection.
+  void Shutdown();
+
   // HTTP server for connection.
   HTTPServer *server_;
 
   // Socket for connection.
   int sock_;
 
+  // Last time event was received on connection.
+  time_t last_;
+
   // HTTP connection list.
   HTTPConnection *next_;
   HTTPConnection *prev_;