Am 03.06.2016 um 10:48 hat Fam Zheng geschrieben: > They are wrappers of POSIX fcntl "file private locking". > > Signed-off-by: Fam Zheng <f...@redhat.com> > --- > include/qemu/osdep.h | 2 ++ > util/osdep.c | 29 +++++++++++++++++++++++++++++ > 2 files changed, 31 insertions(+) > > diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h > index 6937694..749214a 100644 > --- a/include/qemu/osdep.h > +++ b/include/qemu/osdep.h > @@ -280,6 +280,8 @@ int qemu_madvise(void *addr, size_t len, int advice); > > int qemu_open(const char *name, int flags, ...); > int qemu_close(int fd); > +int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); > +int qemu_unlock_fd(int fd, int64_t start, int64_t len); > > #if defined(__HAIKU__) && defined(__i386__) > #define FMT_pid "%ld" > diff --git a/util/osdep.c b/util/osdep.c > index 9a7a439..085ed52 100644 > --- a/util/osdep.c > +++ b/util/osdep.c > @@ -137,6 +137,35 @@ static int qemu_parse_fdset(const char *param) > { > return qemu_parse_fd(param); > } > + > +static int qemu_lock_fcntl(int fd, int64_t start, int64_t len, int fl_type) > +{ > +#ifdef F_OFD_SETLK > + int ret; > + struct flock fl = { > + .l_whence = SEEK_SET, > + .l_start = start, > + .l_len = len, > + .l_type = fl_type, > + }; > + do { > + ret = fcntl(fd, F_OFD_SETLK, &fl); > + } while (ret == -1 && errno == EINTR); > + return ret == -1 ? -errno : 0; > +#else > + return -ENOTSUP; > +#endif > +}
This will return -ENOTSUP in the case that the function wasn't available at build time, but -EINVAL if it was available at build time but the kernel doesn't support it at runtime. Should we unify this? Kevin