Daniel P. Berrangé <berra...@redhat.com> writes: > qemu_open_old() works like open(): set errno and return -1 on failure. > It has even more failure modes, though. Reporting the error clearly > to users is basically impossible for many of them. > > Our standard cure for "errno is too coarse" is the Error object. > Introduce two new helper methods: > > int qemu_open(const char *name, int flags, Error **errp); > int qemu_create(const char *name, int flags, mode_t mode, Error **errp); > > Note that with this design we no longer require or even accept the > O_CREAT flag. Avoiding overloading the two distinct operations > means we can avoid variable arguments which would prevent 'errp' from > being the last argument. It also gives us a guarantee that the 'mode' is > given when creating files, avoiding a latent security bug. > > Signed-off-by: Daniel P. Berrangé <berra...@redhat.com> > --- > include/qemu/osdep.h | 6 ++++++ > util/osdep.c | 21 +++++++++++++++++---- > 2 files changed, 23 insertions(+), 4 deletions(-) > > diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h > index 18333e9006..13a821845b 100644 > --- a/include/qemu/osdep.h > +++ b/include/qemu/osdep.h > @@ -497,7 +497,13 @@ int qemu_madvise(void *addr, size_t len, int advice); > int qemu_mprotect_rwx(void *addr, size_t size); > int qemu_mprotect_none(void *addr, size_t size); > > +/* > + * Don't introduce new usage of this function, prefer the following > + * qemu_open/qemu_create that take an "Error **errp" > + */ > int qemu_open_old(const char *name, int flags, ...); > +int qemu_open(const char *name, int flags, Error **errp); > +int qemu_create(const char *name, int flags, mode_t mode, Error **errp); > int qemu_close(int fd); > int qemu_unlink(const char *name); > #ifndef _WIN32 > diff --git a/util/osdep.c b/util/osdep.c > index 9c7118d3cb..a4956fbf6b 100644 > --- a/util/osdep.c > +++ b/util/osdep.c > @@ -344,10 +344,7 @@ qemu_open_internal(const char *name, int flags, mode_t > mode, Error **errp) > #endif /* ! O_CLOEXEC */ > > if (ret == -1) { > - const char *action = "open"; > - if (flags & O_CREAT) { > - action = "create"; > - } > + const char *action = flags & O_CREAT ? "create" : "open"; > error_setg_errno(errp, errno, "Could not %s '%s' flags 0x%x", > action, name, flags); > }
Squash this hunk into PATCH 3, please. > @@ -357,6 +354,22 @@ qemu_open_internal(const char *name, int flags, mode_t > mode, Error **errp) > } > > > +int qemu_open(const char *name, int flags, Error **errp) > +{ > + assert(!(flags & O_CREAT)); > + > + return qemu_open_internal(name, flags, 0, errp); > +} > + > + > +int qemu_create(const char *name, int flags, mode_t mode, Error **errp) > +{ > + assert(!(flags & O_CREAT)); > + > + return qemu_open_internal(name, flags | O_CREAT, mode, errp); > +} > + > + > int qemu_open_old(const char *name, int flags, ...) > { > va_list ap; Other than that: Reviewed-by: Markus Armbruster <arm...@redhat.com>