[libvirt] [PATCH 2/7] storage: Make the adapter name be consistent with node device driver

[Osier Yang]

node device driver names the HBA like "scsi_host5", but storage
driver uses "host5", which could make the user confused. This
changes them to be consistent. However, for back-compat reason,
adapter name like "host5" is still supported.

v1 - v2:
  * Use virStrToLong_ui instead of sscanf
  * No tests addition or changes, because this patch only affects
    the way scsi backend works for adapter, adding xml2xml tests for
    it is just meaningless.
---
 docs/formatstorage.html.in         | 15 ++++++-----
 src/storage/storage_backend_scsi.c | 54 +++++++++++++++++++++++++++++---------
 2 files changed, 50 insertions(+), 19 deletions(-)

diff --git a/docs/formatstorage.html.in b/docs/formatstorage.html.in
index eff3016..5fae933 100644
--- a/docs/formatstorage.html.in
+++ b/docs/formatstorage.html.in
@@ -89,13 +89,14 @@
       <dt><code>adapter</code></dt>
       <dd>Provides the source for pools backed by SCSI adapters. May
         only occur once. Attribute <code>name</code> is the SCSI adapter
-        name (ex. "host1"). Attribute <code>type</code>
-        (<span class="since">1.0.4</span>) specifies the adapter type.
-        Valid value are "fc_host" and "scsi_host".  If omitted and
-        the <code>name</code> attribute is specified, then it defaults to
-        "scsi_host". To keep backwards compatibility, the attribute
-        <code>type</code> is optional for the "scsi_host" adapter, but
-        mandatory for the "fc_host" adapter.  Attributes <code>wwnn</code>
+        name (ex. "scsi_host1". NB, although a name such as "host1" is
+        still supported for backwards compatibility, it is not recommended).
+        Attribute <code>type</code> (<span class="since">1.0.4</span>)
+        specifies the adapter type. Valid value are "fc_host" and "scsi_host".
+        If omitted and the <code>name</code> attribute is specified, then it
+        defaults to "scsi_host". To keep backwards compatibility, the
+        attribute <code>type</code> is optional for the "scsi_host" adapter,
+        but mandatory for the "fc_host" adapter.  Attributes <code>wwnn</code>
         (Word Wide Node Name) and <code>wwpn</code> (Word Wide Port Name)
         (<span class="since">1.0.4</span>) are used by the "fc_host" adapter
         to uniquely indentify the device in the Fibre Channel storage farbic
diff --git a/src/storage/storage_backend_scsi.c b/src/storage/storage_backend_scsi.c
index c1c163e..cc1ebe2 100644
--- a/src/storage/storage_backend_scsi.c
+++ b/src/storage/storage_backend_scsi.c
@@ -632,14 +632,49 @@ out:
 }
 
 static int
+getHostNumber(const char *adapter_name,
+              unsigned int *result)
+{
+    char *host = (char *)adapter_name;
+
+    /* Specifying adapter like 'host5' is still supported for
+     * back-compat reason.
+     */
+    if (STRPREFIX(host, "scsi_host")) {
+        host += strlen("scsi_host");
+    } else if (STRPREFIX(host, "host")) {
+        host += strlen("host");
+    } else {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("invalid adapter name '%s' for scsi pool"),
+                       adapter_name);
+        return -1;
+    }
+
+    if (result && virStrToLong_ui(host, NULL, 10, result) == -1) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("invalid adapter name '%s' for scsi pool"),
+                       adapter_name);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int
 virStorageBackendSCSICheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
                                virStoragePoolObjPtr pool,
                                bool *isActive)
 {
     char *path;
+    unsigned int host;
 
     *isActive = false;
-    if (virAsprintf(&path, "/sys/class/scsi_host/%s", pool->def->source.adapter.data.name) < 0) {
+
+    if (getHostNumber(pool->def->source.adapter.data.name, &host) < 0)
+        return -1;
+
+    if (virAsprintf(&path, "/sys/class/scsi_host/host%d", host) < 0) {
         virReportOOMError();
         return -1;
     }
@@ -656,29 +691,24 @@ static int
 virStorageBackendSCSIRefreshPool(virConnectPtr conn ATTRIBUTE_UNUSED,
                                  virStoragePoolObjPtr pool)
 {
-    int retval = 0;
-    uint32_t host;
+    int ret = -1;
+    unsigned int host;
 
     pool->def->allocation = pool->def->capacity = pool->def->available = 0;
 
-    if (sscanf(pool->def->source.adapter.data.name, "host%u", &host) != 1) {
-        VIR_DEBUG("Failed to get host number from '%s'",
-                    pool->def->source.adapter.data.name);
-        retval = -1;
+    if (getHostNumber(pool->def->source.adapter.data.name, &host) < 0)
         goto out;
-    }
 
     VIR_DEBUG("Scanning host%u", host);
 
-    if (virStorageBackendSCSITriggerRescan(host) < 0) {
-        retval = -1;
+    if (virStorageBackendSCSITriggerRescan(host) < 0)
         goto out;
-    }
 
     virStorageBackendSCSIFindLUs(pool, host);
 
+    ret = 0;
 out:
-    return retval;
+    return ret;
 }
 
 
-- 
1.8.0.1