Redirected to devel@ On Sun, 7 Mar 2004, Peter Breitenlohner wrote:
> Dear XFree86 maintainers, > I fully understand that XFree86 has to support IPv6. The current > implementation has, however, a serious flaw: when compiled with IPv6 support > (which is the default for most linux/gnu systems) the progams implicitly > assume that IPv6 is supported by the kernel. In our case that is not so, and > in order to get things working I had to > #define BuildIPv6 NO > in xc/config/cf/host.def, thereby permanantly disabling IPv6 support. > It would be extremely helpful if one could compile XFree86 with IPv6 > support, but then disable IPv6 at runtime via configuration files > (resources) and/or command line options (in order to avoid various > timeouts), and the programs should automatically fall back to IPv4 in case > IPv6 is not supported by the kernel. > The actual problems encountered were twofold: > 1. xdm produced an error message > chooser socket creation failed > and there was just a useless parent process but no child process(es) and no > Xserver was started. I think the lines 69ff in xc/programs/xdm/socket.c > #if defined(IPv6) && defined(AF_INET6) > chooserFd = socket (AF_INET6, SOCK_STREAM, 0); > #else > chooserFd = socket (AF_INET, SOCK_STREAM, 0); > #endif > ought to be > #if defined(IPv6) && defined(AF_INET6) > chooserFd = socket (AF_INET6, SOCK_STREAM, 0); > if (chooserFd == -1) > #endif > chooserFd = socket (AF_INET, SOCK_STREAM, 0); > although I haven't tested this. > 2. Trying to start chooser by hand lead to a segmentation fault! With a > little tracing I found the following code in xc/programs/xdm/chooser.c in > lines 844ff > #if defined(IPv6) && defined(AF_INET6) > socket6FD = socket (AF_INET6, SOCK_DGRAM, 0); > #endif > and later in lines 856ff > XtAddInput (socketFD, (XtPointer) XtInputReadMask, ReceivePacket, > (XtPointer) &socketFD); > #if defined(IPv6) && defined(AF_INET6) > XtAddInput (socket6FD, (XtPointer) XtInputReadMask, ReceivePacket, > (XtPointer) &socket6FD); > #endif > The second code fragment certainly ought to be > XtAddInput (socketFD, (XtPointer) XtInputReadMask, ReceivePacket, > (XtPointer) &socketFD); > #if defined(IPv6) && defined(AF_INET6) > if (socket6FD != -1) > XtAddInput (socket6FD, (XtPointer) XtInputReadMask, ReceivePacket, > (XtPointer) &socket6FD); > #endif > but that may not suffice. Calling XtAddInput with a untested first argument > is just asking for serious trouble. Please check if your changes actually fix the problem. Thanks. Marc. +----------------------------------+-----------------------------------+ | Marc Aurele La France | work: 1-780-492-9310 | | Computing and Network Services | fax: 1-780-492-1729 | | 352 General Services Building | email: [EMAIL PROTECTED] | | University of Alberta +-----------------------------------+ | Edmonton, Alberta | | | T6G 2H1 | Standard disclaimers apply | | CANADA | | +----------------------------------+-----------------------------------+ XFree86 developer and VP. ATI driver and X server internals. _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
