Re: [libvirt] [PATCH 5/9] virstoragefile: Treat backingStore as a pointer or an array

As explain in the former patchs, backingStore can be treat an array or a pointer. If we have only one backingStore we have to use it as a normal ptr but if there is more backing store, we use it as a pointer's array. Because it would be complicated to expend backingStore manually, and do the convertion from a pointer to an array, I've created the virStorageSourcePushBackingStore function to help. This function allocate an array of pointer only if there is more than 1 bs. Because we can not remove a child from a quorum, i didn't create the function virStorageSourcePopBackingStore. I've changed virStorageSourceBackingStoreClear, virStorageSourceSetBackingStore and virStorageSourceGetBackingStore to handle the case where backingStore is an array. Signed-off-by: Matthias Gatto <matthias.gatto(a)outscale.com&gt; --- src/conf/storage_conf.c | 3 +- src/libvirt_private.syms | 1 + src/storage/storage_backend_fs.c | 2 +- src/storage/storage_backend_logical.c | 2 +- src/util/virstoragefile.c | 87 ++++++++++++++++++++++++++++++++--- src/util/virstoragefile.h | 2 + 6 files changed, 87 insertions(+), 10 deletions(-)

diff --git a/src/storage/storage_backend_logical.c b/src/storage/storage_backend_logical.c index 300c990..edec124 100644 --- a/src/storage/storage_backend_logical.c +++ b/src/storage/storage_backend_logical.c

+/** + * virStorageSourcePushBackingStore: + * @src: virStorageSourcePtr to allocate the new backing store + * + * Allocate size for a new backing store in src->backingStore + * and update src->nBackingStores + * If we have less than 2 backing stores, we treat src->backingStore + * as a pointer otherwise we treat it as an array of virStorageSourcePtr + */ +bool +virStorageSourcePushBackingStore(virStorageSourcePtr src) +{ + virStorageSourcePtr tmp; + virStorageSourcePtr *tmp2; + + if (src->nBackingStores == 1) { +/* If we need more than one backing store we need an array + * Because we don't want to lose our data from the old Backing Store + * we copy the pointer from src->backingStore to src->backingStore[0] */

+ tmp = src->backingStore; + if (VIR_ALLOC_N(tmp2, 1) < 0) + return false; + src->backingStore = (virStorageSourcePtr)tmp2; + src->nBackingStores += 1; + virStorageSourceSetBackingStore(src, tmp, 0); + } else if (src->nBackingStores > 1) { + tmp2 = ((virStorageSourcePtr *)src->backingStore); + if (VIR_EXPAND_N(tmp2, src->nBackingStores, 1) < 0) + return false; + src->backingStore = (virStorageSourcePtr)tmp2; + } else { +/* Most of the time we use only one backingStore + * So we don't need to allocate an array */ + src->nBackingStores += 1; + } + return true; +} +