Re: [libvirt] [PATCH 1/3 RFC] Add function to get the network interface name of a pci device
On 8/1/11 6:00 PM, "Stefan Berger" <stefanb(a)linux.vnet.ibm.com> wrote:
On 08/01/2011 07:57 PM, Roopa Prabhu wrote:
> From: Roopa Prabhu<roprabhu(a)cisco.com>
>
> This function looks at sysfs "net" directory to get the network interface
> name associated with the pci device
>
> Signed-off-by: Roopa Prabhu<roprabhu(a)cisco.com>
> Signed-off-by: Christian Benvenuti<benve(a)cisco.com>
> Signed-off-by: David Wang<dwang2(a)cisco.com>
> ---
> src/util/pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> src/util/pci.h | 2 ++
> 2 files changed, 44 insertions(+), 0 deletions(-)
>
>
> diff --git a/src/util/pci.c b/src/util/pci.c
> index a79c164..d2deeef 100644
> --- a/src/util/pci.c
> +++ b/src/util/pci.c
> @@ -1679,3 +1679,45 @@ int pciDeviceIsAssignable(pciDevice *dev,
>
> return 1;
> }
> +
> +/*
> + * This function returns the network device name
> + * of a pci device
> + */
> +int
> +pciDeviceGetNetName(char *device_link_sysfs_path, char **netname)
> +{
> + char *pcidev_sysfs_net_path = NULL;
> + int ret = -1;
> + DIR *dir = NULL;
> + struct dirent *entry = NULL;
> +
> + if (virBuildPath(&pcidev_sysfs_net_path, device_link_sysfs_path,
> + "net") == -1) {
> + virReportOOMError();
> + return -1;
> + }
> +
> + dir = opendir(pcidev_sysfs_net_path);
> + if (dir == NULL)
> + goto out;
> +
> + while ((entry = readdir(dir))) {
> + if (entry->d_name[0] == '.' ||
The above check makes the following one obsolete. If all entries with
first letter '.' can be skipped, then you could just keep the first one,
otherwise I'd also use !strcmp(entry->d_name, ".").
Agree, yes I should use strcmp. Did not think of all cases here because the
net dir normally contains one entry. I will also revisit this check for
cases when there might be more net devices associated with a pci device.
> + !strcmp(entry->d_name, ".."))
> + continue;
> +
> + /* Assume a single directory entry */
> + *netname = strdup(entry->d_name);
> + ret = 0;
> + break;
> + }
> +
> + if (dir)
> + closedir(dir);
Check for 'dir != NULL) is not necessary due to goto above.
Yes will fix. Thanks stefan.
> +
> +out:
> + VIR_FREE(pcidev_sysfs_net_path);
> +
> + return ret;
> +}
> diff --git a/src/util/pci.h b/src/util/pci.h
> index a351baf..fa25472 100644
> --- a/src/util/pci.h
> +++ b/src/util/pci.h
> @@ -74,4 +74,6 @@ int pciDeviceIsAssignable(pciDevice *dev,
> int strict_acs_check);
> int pciWaitForDeviceCleanup(pciDevice *dev, const char *matcher);
>
> +int pciDeviceGetNetName(char *device_link_sysfs_path, char **netname);
> +
> #endif /* __VIR_PCI_H__ */
>
Stefan