[libvirt] [PATCH] util: allow creation of file with virFileWriteStr

[Matthias Bolte]

2010/12/3 Eric Blake <eblake at redhat.com>:
> Making this change will allow the future patches to use
> virFileWriteStr to create a file, rather than its current limitation
> of only working on pre-existing files.
>
> * src/util/util.h (virFileWriteStr): Alter signature.
> * src/util/util.c (virFileWriteStr): Allow file creation.
> * src/network/bridge_driver.c (networkEnableIpForwarding)
> (networkDisableIPV6): Adjust clients.
> * src/node_device/node_device_driver.c
> (nodeDeviceVportCreateDelete): Likewise.
> * src/util/cgroup.c (virCgroupSetValueStr): Likewise.
> * src/util/pci.c (pciBindDeviceToStub, pciUnBindDeviceFromStub):
> Likewise.
> Based on a report from Jean-Baptiste Rouault.
> ---
>
>> Alternatively, I only counted 16 existing users of virFileWriteStr; and
>> this is an internal API.  We could easily rewrite all clients to always
>> pass a third parameter, and change the signature of virFileWriteStr to
>> require a mode_t argument.  Hmm; some of those clients are writing to
>> kernel files that should always exist (/proc/sys/net/ipv4/ip_forward,
>> for example), where it's tough to justify what we would pass as a mode_t
>> argument.  So maybe pass mode==0 as a sentinel to require a pre-existing
>> file
>
> How does this look?  Admittedly, all existing uses were okay with a
> mode parameter of 0; and I haven't yet seen your patch that would
> use a non-zero mode, but this still makes more sense to me.
>
> Oh, and VIR_FORCE_CLOSE preserves errno, so I was able to simplify
> virFileWriteStr in the process.
>
>  src/network/bridge_driver.c          |    8 ++++----
>  src/node_device/node_device_driver.c |    2 +-
>  src/util/cgroup.c                    |    2 +-
>  src/util/pci.c                       |   16 ++++++++--------
>  src/util/util.c                      |   13 ++++++++-----
>  src/util/util.h                      |    3 ++-
>  6 files changed, 24 insertions(+), 20 deletions(-)
>

ACK.

Matthias