From: David Reiss <dreiss@apache.org>
Date: Tue, 8 Apr 2008 06:26:27 +0000 (+0000)
Subject: Use poll instead of select in TServerSocket
X-Git-Tag: 0.2.0~823
X-Git-Url: https://source.supwisdom.com/gerrit/gitweb?a=commitdiff_plain;h=1677ac9cc7550ea3eb4a4e46fbcf16790c2cb70c;p=common%2Fthrift.git

Use poll instead of select in TServerSocket

Summary: - select has a restricted max fd set size. While this should not be an issue in the normal case for
           TServerSocket because it is started when the process starts, it could be a problem if someone wanted
           to start a new server socket at a later point in time when socket values could be greater than max.

Reviewed By: dreiss

Test Plan: - Compiled.
           - Deployed search tier and made sure it could serve queries.

Revert: OK

TracCamp Project: Thrift

DiffCamp Revision: 11076


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665649 13f79535-47bb-0310-9956-ffa450edef68
---

diff --git a/lib/cpp/src/transport/TServerSocket.cpp b/lib/cpp/src/transport/TServerSocket.cpp
index 2b4e7c34..1bfc56bc 100644
--- a/lib/cpp/src/transport/TServerSocket.cpp
+++ b/lib/cpp/src/transport/TServerSocket.cpp
@@ -5,7 +5,7 @@
 // http://developers.facebook.com/thrift/
 
 #include <sys/socket.h>
-#include <sys/select.h>
+#include <sys/poll.h>
 #include <sys/types.h>
 #include <netinet/in.h>
 #include <netinet/tcp.h>
@@ -246,18 +246,20 @@ shared_ptr<TTransport> TServerSocket::acceptImpl() {
     throw TTransportException(TTransportException::NOT_OPEN, "TServerSocket not listening");
   }
 
-  fd_set fds;
+  struct pollfd fds[2];
 
   int maxEintrs = 5;
   int numEintrs = 0;
 
   while (true) {
-    FD_ZERO(&fds);
-    FD_SET(serverSocket_, &fds);
+    memset(fds, 0 , sizeof(fds));
+    fds[0].fd = serverSocket_;
+    fds[0].events = POLLIN;
     if (intSock2_ >= 0) {
-      FD_SET(intSock2_, &fds);
+      fds[1].fd = intSock2_;
+      fds[1].fd = POLLIN;
     }
-    int ret = select(serverSocket_+1, &fds, NULL, NULL, NULL);
+    int ret = poll(fds, 2, -1);
 
     if (ret < 0) {
       // error cases
@@ -272,7 +274,7 @@ shared_ptr<TTransport> TServerSocket::acceptImpl() {
       throw TTransportException(TTransportException::UNKNOWN, "Unknown", errno_copy);
     } else if (ret > 0) {
       // Check for an interrupt signal
-      if (intSock2_ >= 0 && FD_ISSET(intSock2_, &fds)) {
+      if (intSock2_ >= 0 && (fds[1].revents & POLLIN)) {
         int8_t buf;
         if (-1 == recv(intSock2_, &buf, sizeof(int8_t), 0)) {
           int errno_copy = errno;
@@ -283,11 +285,11 @@ shared_ptr<TTransport> TServerSocket::acceptImpl() {
       }
 
       // Check for the actual server socket being ready
-      if (FD_ISSET(serverSocket_, &fds)) {
+      if (fds[0].revents & POLLIN) {
         break;
       }
     } else {
-      GlobalOutput("TServerSocket::acceptImpl() select 0");
+      GlobalOutput("TServerSocket::acceptImpl() poll 0");
       throw TTransportException(TTransportException::UNKNOWN);
     }
   }