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Possible causes of a deadlock in socket select

bool ConnectionTCPBase::dataAvailable( int timeout )

  {

    if( m_socket < 0 )

      return true; // let recv() catch the closed fd

 

    fd_set fds;

    struct timeval tv;

 

    FD_ZERO( &fds );

    // the following causes a C4127 warning in VC++ Express 2008 and possibly other versions.

    // however, the reason for the warning can't be fixed in gloox.

    FD_SET( m_socket, &fds );

 

    tv.tv_sec = timeout / 1000000;

    tv.tv_usec = timeout % 1000000;

 

    return ( ( select( m_socket + 1, &fds, 0, 0, timeout == -1 ? 0 : &tv ) > 0 )

             && FD_ISSET( m_socket, &fds ) != 0 );

  }

       

Thread 2 (Thread 0x7fe226ac2700 (LWP 10774)):

#0  0x00007fe224711ff3 in select () at ../sysdeps/unix/syscall-template.S:82

#1  0x00000000004706a9 in gloox::ConnectionTCPBase::dataAvailable (this=0xcaeb60, timeout=<value optimized out>) at connectiontcpbase.cpp:103

#2  0x000000000046c4cb in gloox::ConnectionTCPClient::recv (this=0xcaeb60, timeout=10) at connectiontcpclient.cpp:131

#3  0x0000000000471476 in gloox::ConnectionTLS::recv (this=0xd1a950, timeout=648813712) at connectiontls.cpp:89

#4  0x00000000004324cc in glooxd::C2S::recv (this=0xc5d120, timeout=10) at c2s.cpp:124

#5  0x0000000000435ced in glooxd::C2S::run (this=0xc5d120) at c2s.cpp:75

#6  0x000000000042d789 in CNetwork::run (this=0xc56df0) at src/Network.cpp:343

#7  0x000000000043115f in threading::ThreadManager::threadWorker (data=0xc56e10) at src/ThreadManager.cpp:15

#8  0x00007fe2249bc9ca in start_thread (arg=<value optimized out>) at pthread_create.c:300

#9  0x00007fe22471970d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112

#10 0x0000000000000000 in ?? ()

       

// let recv() catch the closed fd

       

fd_set fds_copy = fds;

select( m_socket + 1, &fds, 0, &fds_copy, timeout == -1 ? 0 : &tv )