Hi
perhaps there is an opportunity to do some refactoring here (... for me a "goto " carries a code smell! )

along the lines

if (timeout) {
    nread =  NET_ReadWithTimeout(...);
} else {
     nread = NET_Read(...);
}


the NET_ReadWithTimeout (...) function will contain a restructuring of your goto loop

while (_timeout > 0) { nread = NET_Timeout(fd, _timeout);
          if (nread <= 0) {
              if (nread == 0) {
                  JNU_ThrowByName(env, JNU_JAVANETPKG "SocketTimeoutException",
                              "Read timed out");
              } else if (nread == -1) {
                  if (errno == EBADF) {
                       JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", 
"Socket closed");
                  } else if (errno == ENOMEM) {
                      JNU_ThrowOutOfMemoryError(env, "NET_Timeout native heap 
allocation failed");
                  } else {
                      JNU_ThrowByNameWithMessageAndLastError
                          (env, JNU_JAVANETPKG "SocketException", "select/poll 
failed");
                  }
              }
                // release buffer in main call flow
//              if (bufP != BUF) {
//                  free(bufP);
//             }
             nread = -1;
             break;
          } else {
nread = NET_NonBlockingRead(fd, bufP, len);
if (nread == -1 && ((errno == EAGAIN) || (errno == EWOULDBLOCK))) {
              gettimeofday(&t, NULL);
newtime = t.tv_sec * 1000 + t.tv_usec / 1000;
_timeout -= newtime - prevtime;
if(_timeout > 0){
prevtime = newtime;
                  }
} else { break; } } } return nread;


e&oe

regards
Mark


On 29/08/2016 10:58, Vyom Tewari wrote:
gentle reminder, please review the below code change.

Vyom


On Monday 22 August 2016 05:12 PM, Vyom Tewari wrote:
Hi All,

Please review the code changes for below issue.

Bug         : https://bugs.openjdk.java.net/browse/JDK-8075484

webrev : http://cr.openjdk.java.net/~vtewari/8075484/webrev0.0/index.html <http://cr.openjdk.java.net/%7Evtewari/8075484/webrev0.0/index.html>

This issue is SocketInputStream.socketread0() hangs even with "soTimeout" set.the implementation of Java_java_net_SocketInputStream_socketRead0 assumes that read() won't block after poll() reports that a read is possible.

This assumption does not hold, as noted on the man page for select (referenced by the man page for poll): Under Linux, select() may report a socket file descriptor as "ready for reading", while nevertheless a subsequent read blocks. This could for example happen when data has arrived but upon examination has wrong checksum and is discarded.

Thanks,

Vyom




Reply via email to