diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2015-01-20 23:59:38 -0800 |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@intel.com> | 2015-01-23 19:13:07 +0100 |
| commit | 9931fa9df4cb96a4006a3390db64f87e3b5bc1a0 (patch) | |
| tree | 3ac4a724147ec0c6f66a9c2b06e8ef80c7b4dcb5 | |
| parent | bd1be70e0ef665bae2c28a4f877e4a5a8268de14 (diff) | |
Fix forkfd on OS X 10.7 and earlier
dtruss logs show that the signal handler does enter and is active, since
it does the first waitid() call, but then returns immediately:
waitid(0x0, 0x0, 0x7FFF62D7C468) = 0 0
sigreturn(0x7FFF62D7C9A0, 0x1E, 0x0) = 0 Err#-2
Since there was no error return, we conclude that si_pid was zero on
return. Source code for OS X 10.7 confirms that si_pid is set to zero
unconditionally, which is rather stupid:
http://fxr.watson.org/fxr/source/bsd/kern/kern_exit.c?v=xnu-1699.24.8#L1330
This is fixed for OS X 10.8:
http://fxr.watson.org/fxr/source/bsd/kern/kern_exit.c?v=xnu-2050.18.24#L1399
Without that information, we have to scan each child anyway, so
just disable the waitid() solution on OS X. This is a "hammer" solution
which will get forkfd working. We can later try and detect at runtime
whether waitid() is working.
Change-Id: Ic5d393bfd36e48a193fcffff13bb584927cdeafe
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
| -rw-r--r-- | src/3rdparty/forkfd/forkfd.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/src/3rdparty/forkfd/forkfd.c b/src/3rdparty/forkfd/forkfd.c index 84c979315f..2ad06fe1a5 100644 --- a/src/3rdparty/forkfd/forkfd.c +++ b/src/3rdparty/forkfd/forkfd.c @@ -58,7 +58,18 @@ # include <sys/eventfd.h> #endif -#if _POSIX_VERSION-0 >= 200809L || _XOPEN_VERSION-0 >= 500 +#if defined(__APPLE__) +/* Up until OS X 10.7, waitid(P_ALL, ...) will return success, but will not + * fill in the details of the dead child. That means waitid is not useful to us. + * Therefore, we only enable waitid() support if we're targetting OS X 10.8 or + * later. + */ +# include <Availability.h> +# include <AvailabilityMacros.h> +# if MAC_OS_X_VERSION_MIN_REQUIRED >= 1080 +# define HAVE_WAITID 1 +# endif +#elif _POSIX_VERSION-0 >= 200809L || _XOPEN_VERSION-0 >= 500 # define HAVE_WAITID 1 #endif |