diff options
| author | Steve Huston <shuston@riverace.com> | 2012-04-03 22:55:46 +0000 |
|---|---|---|
| committer | Steve Huston <shuston@riverace.com> | 2012-04-03 22:55:46 +0000 |
| commit | 2897c87e6f9a32e3b75c7fa2bc2eb96a6647afcb (patch) | |
| tree | 545842573f225caaaf5954e6d9fede009470a8ef | |
| parent | 98f80f43d5dbb7dd30338ac8c6c18b67b62c23a6 (diff) | |
| download | ATCD-2897c87e6f9a32e3b75c7fa2bc2eb96a6647afcb.tar.gz | |
ChangeLogTag:Tue Apr 3 22:49:11 UTC 2012 Steve Huston <shuston@riverace.com>
| -rw-r--r-- | ACE/ChangeLog | 10 | ||||
| -rw-r--r-- | ACE/ace/SOCK_Dgram_Mcast.cpp | 16 |
2 files changed, 23 insertions, 3 deletions
diff --git a/ACE/ChangeLog b/ACE/ChangeLog index acc58715c68..07b02982e3d 100644 --- a/ACE/ChangeLog +++ b/ACE/ChangeLog @@ -1,3 +1,13 @@ +Tue Apr 3 22:49:11 UTC 2012 Steve Huston <shuston@riverace.com> + + * ace/SOCK_Dgram_Mcast.cpp (subscribe_ifs): Set the error code when + a Windows API call fails. Also, when calling GetAdaptersAddresses() + to both check size and get the info, supply GAA_FLAG_SKIP_MULTICAST + as the flag value. This avoids obtaining info for joined multicast + addresses, not multicastable interfaces. Without the flag, and if + some other process does a join between the size-check call and the + info-gathering call, the size will be wrong. + Tue Apr 3 17:01:33 UTC 2012 Jeff Parsons <j.parsons@vanderbilt.edu> * THANKS: diff --git a/ACE/ace/SOCK_Dgram_Mcast.cpp b/ACE/ace/SOCK_Dgram_Mcast.cpp index 9e968a47663..a5d5e5e0c16 100644 --- a/ACE/ace/SOCK_Dgram_Mcast.cpp +++ b/ACE/ace/SOCK_Dgram_Mcast.cpp @@ -327,12 +327,21 @@ ACE_SOCK_Dgram_Mcast::subscribe_ifs (const ACE_INET_Addr &mcast_addr, // Initial call to determine actual memory size needed DWORD dwRetVal; ULONG bufLen = 0; + // Note... GetAdaptersAddresses returns different bufLen values depending + // on how many multicast joins there are on the system. To avoid this, + // specify that we don't want to know about multicast addresses. This + // does not avoid multicastable interfaces and makes the size-check + // more reliable across varying conditions. + DWORD flags = GAA_FLAG_SKIP_MULTICAST; if ((dwRetVal = ::GetAdaptersAddresses (family, - 0, + flags, 0, &tmp_addrs, &bufLen)) != ERROR_BUFFER_OVERFLOW) - return -1; // With output bufferlength 0 this can't be right. + { + errno = dwRetVal; + return -1; // With output bufferlength 0 this can't be right. + } // Get required output buffer and retrieve info for real. PIP_ADAPTER_ADDRESSES pAddrs; @@ -342,12 +351,13 @@ ACE_SOCK_Dgram_Mcast::subscribe_ifs (const ACE_INET_Addr &mcast_addr, -1); pAddrs = reinterpret_cast<PIP_ADAPTER_ADDRESSES> (buf); if ((dwRetVal = ::GetAdaptersAddresses (family, - 0, + flags, 0, pAddrs, &bufLen)) != NO_ERROR) { delete[] buf; // clean up + errno = dwRetVal; return -1; } |