[libvirt] [PATCH v8 1/5] virstoragefile: Add helper to get storage source backingStore

From: Matthias Gatto <matthias.gatto(a)outscale.com&gt; Add a new helper - virStorageSourceGetBackingStore - to fetch the storage source backingStore pointer in order to make it easier to change the future format of the data. A future patch will adjust the backingStore pointer to become a table or array of backingStorePtr's accessible by the argument 'pos'. For now, if 'pos' > 0, the code will return NULL as if the backingStore pointer didn't exist. All callers in subsequent patches will start by passing a 0 as the parameter. Signed-off-by: Matthias Gatto <matthias.gatto(a)outscale.com&gt; Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/libvirt_private.syms | 1 + src/util/virstoragefile.c | 23 +++++++++++++++++++++++ src/util/virstoragefile.h | 3 +++ 3 files changed, 27 insertions(+) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 55822ae..1c55370 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2196,6 +2196,7 @@ virStorageSourceClear; virStorageSourceCopy; virStorageSourceFree; virStorageSourceGetActualType; +virStorageSourceGetBackingStore; virStorageSourceGetSecurityLabelDef; virStorageSourceInitChainElement; virStorageSourceIsEmpty; diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c index 2aa1d90..2771c95 100644 --- a/src/util/virstoragefile.c +++ b/src/util/virstoragefile.c @@ -1810,6 +1810,29 @@ virStorageSourcePoolDefCopy(const virStorageSourcePoolDef *src) /** + * virStorageSourceGetBackingStore: + * @src: virStorageSourcePtr containing the backing stores + * @pos: presently unused + * + * Return the @src backingStore pointer at @pos. For now, @pos is + * expected to be 0. A future patch will use @pos index into an array + * of storage backingStore pointers + * + * Returns: + * A pointer to the storage source backingStore @pos or + * NULL if the backingStore pointer cannot be found + */ +virStorageSourcePtr +virStorageSourceGetBackingStore(const virStorageSource *src, + size_t pos) +{ + if (!src || pos > 0) + return NULL; + return src->backingStore; +} + + +/** * virStorageSourcePtr: * * Deep-copies a virStorageSource structure. If @backing chain is true diff --git a/src/util/virstoragefile.h b/src/util/virstoragefile.h index b98fe25..8cd4854 100644 --- a/src/util/virstoragefile.h +++ b/src/util/virstoragefile.h @@ -289,6 +289,9 @@ struct _virStorageSource { # define DEV_BSIZE 512 # endif +virStorageSourcePtr virStorageSourceGetBackingStore(const virStorageSource *src, + size_t pos); + int virStorageFileProbeFormat(const char *path, uid_t uid, gid_t gid); int virStorageFileProbeFormatFromBuf(const char *path, char *buf, -- 2.5.0