Re: [libvirt] [PATCH] virprocess: Extend list of platforms for setns wrapper

On 15.09.2014 16:20, Pavel Hrdina wrote: > On 09/15/2014 03:43 PM, Michal Privoznik wrote: >> Currently, the setns() wrapper is supported only for x86_64 and i686 >> which leaves us failing to build on other platforms like arm, aarch64 >> and so on. This means, that the wrapper needs to be extended to those >> platforms and make to fail on runtime not compile time. >> >> The syscall numbers for other platforms was fetched using this >> command: >> >> kernel.git $ git grep "define.*__NR_setns" | grep -e arm -e powerpc -e >> s390 >> arch/arm/include/uapi/asm/unistd.h:#define >> __NR_setns (__NR_SYSCALL_BASE+375) >> arch/arm64/include/asm/unistd32.h:#define __NR_setns 375 >> arch/powerpc/include/uapi/asm/unistd.h:#define >> __NR_setns 350 >> arch/s390/include/uapi/asm/unistd.h:#define __NR_setns 339 >> >> Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; >> --- >> src/util/virprocess.c | 18 ++++++++++++------ >> 1 file changed, 12 insertions(+), 6 deletions(-) >> >> diff --git a/src/util/virprocess.c b/src/util/virprocess.c >> index 3dae1bd..eac49f5 100644 >> --- a/src/util/virprocess.c >> +++ b/src/util/virprocess.c >> @@ -71,27 +71,33 @@ VIR_LOG_INIT("util.process"); >> # define __NR_setns 308 >> # elif defined(__i386__) >> # define __NR_setns 346 >> -# else >> -# error "__NR_setns is not defined" >> +# elif defined(__arm__) >> +# define __NR_setns 375 >> +# elif defined(__aarch64__) >> +# define __NR_setns 375 >> +# elif defined(__powerpc__) >> +# define __NR_setns 350 >> +# elif defined(__s390__) >> +# define __NR_setns 339 >> # endif >> #endif >> >> #ifndef HAVE_SETNS >> -# ifndef WIN32 >> +# ifdef __NR_setns > > This would work only if the macro wasn't defined in kernel, but it seems > that it's defined also for WIN32. Oh my, why the heck do they claim something is supported when it's clearly not?! This needs to be squashed in then: diff --git a/src/util/virprocess.c b/src/util/virprocess.c index eac49f5..806e7f9 100644 --- a/src/util/virprocess.c +++ b/src/util/virprocess.c @@ -83,21 +83,21 @@ VIR_LOG_INIT("util.process"); #endif #ifndef HAVE_SETNS -# ifdef __NR_setns +# if defined(__NR_setns) && !defined(WIN32) # include <sys/syscall.h> static inline int setns(int fd, int nstype) { return syscall(__NR_setns, fd, nstype); } -# else /* __NR_setns */ +# else /* __NR_setns && !WIN32 */ static inline int setns(int fd ATTRIBUTE_UNUSED, int nstype ATTRIBUTE_UNUSED) { virReportSystemError(ENOSYS, "%s", _("Namespaces are not supported on this platform.")); return -1; } -# endif /* __NR_setns */ +# endif /* __NR_setns && !WIN32 */ #endif /* HAVE_SETNS */ /** The other approach would be just to require new enough glibc. Opinions?