Re: [libvirt] [PATCH 17/25] utils: Add a helper to get the device name that sg device mapped to

On 05/03/2013 02:07 PM, Osier Yang wrote: > E.g. > > % sg_map > /dev/sg0 /dev/sda > /dev/sg1 /dev/sr0 > > What the helper gets for /dev/sg0 is /dev/sda, it will be used by > later patch. > --- > src/libvirt_private.syms | 1 + > src/util/virscsi.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ > src/util/virscsi.h | 4 ++++ > 3 files changed, 52 insertions(+) > > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms > index fa59c14..8a7105c 100644 > --- a/src/libvirt_private.syms > +++ b/src/libvirt_private.syms > @@ -1692,6 +1692,7 @@ virSCSIDeviceFileIterate; > virSCSIDeviceFree; > virSCSIDeviceGetAdapter; > virSCSIDeviceGetBus; > +virSCSIDeviceGetDevName; > virSCSIDeviceGetName; > virSCSIDeviceGetReadonly; > virSCSIDeviceGetSgName; > diff --git a/src/util/virscsi.c b/src/util/virscsi.c > index 7d3d40e..f337c75 100644 > --- a/src/util/virscsi.c > +++ b/src/util/virscsi.c > @@ -143,6 +143,53 @@ cleanup: > return sg; > } > > +/* Returns device name (e.g. "sdc") on success, or NULL > + * on failure. > + */ > +char * > +virSCSIDeviceGetDevName(const char *adapter, > + unsigned int bus, > + unsigned int target, > + unsigned int unit) > +{ > + DIR *dir = NULL; > + struct dirent *entry; > + char *path = NULL; > + char *name = NULL; > + unsigned int adapter_id; > + > + if (virSCSIDeviceGetAdapterId(adapter, &adapter_id) < 0) > + return NULL; > + > + if (virAsprintf(&path, > + SYSFS_SCSI_DEVICES "/%d:%d:%d:%d/block", > + adapter_id, bus, target, unit) < 0) { > + virReportOOMError(); > + return NULL; > + } > + > + if (!(dir = opendir(path))) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Failed to open %s"), path); > + goto cleanup; > + } > + > + while ((entry = readdir(dir))) { > + if (entry->d_name[0] == '.') > + continue; > + > + if (!(name = strdup(entry->d_name))) { > + virReportOOMError(); > + goto cleanup; > + } If 'name' then what - we go back to the top of the loop and if there's more entries then we'll strdup() another name.... Although I have to wonder if there can be more than non hidden entry in the list... Makes me wonder about my earlier reviews which didn't think about the loop exit (that is virSCSIDeviceGetSgName())