[libvirt] [PATCH] util: use VIR_(APPEND|DELETE)_ELEMENT for pci/usb device lists

[Laine Stump]

Eliminate memmove() by using VIR_*_ELEMENT API instead.

In both pci and usb cases, the count that held the size of the list
was unsigned int so it had to be changed to size_t.
---
This is an alternate fix to the same problem fixed by

  https://www.redhat.com/archives/libvir-list/2013-July/msg00324.html

(an off by one bug in the conditional in virUSBDeviceListSteal()).

This version fixes it by converting from open coded memmoves to using
VIR_(INSERT|DELETE)_ELEMENT.

 src/util/virpci.c | 18 +++---------------
 src/util/virusb.c | 26 +++++++-------------------
 2 files changed, 10 insertions(+), 34 deletions(-)

diff --git a/src/util/virpci.c b/src/util/virpci.c
index e42f6fa..b715122 100644
--- a/src/util/virpci.c
+++ b/src/util/virpci.c
@@ -80,7 +80,7 @@ struct _virPCIDevice {
 struct _virPCIDeviceList {
     virObjectLockable parent;
 
-    unsigned int count;
+    size_t count;
     virPCIDevicePtr *devs;
 };
 
@@ -1670,11 +1670,9 @@ virPCIDeviceListAdd(virPCIDeviceListPtr list,
         return -1;
     }
 
-    if (VIR_REALLOC_N(list->devs, list->count+1) < 0)
+    if (VIR_APPEND_ELEMENT(list->devs, list->count, dev, true) < 0)
         return -1;
 
-    list->devs[list->count++] = dev;
-
     return 0;
 }
 
@@ -1723,17 +1721,7 @@ virPCIDeviceListStealIndex(virPCIDeviceListPtr list,
         return NULL;
 
     ret = list->devs[idx];
-
-    if (idx != --list->count) {
-        memmove(&list->devs[idx],
-                &list->devs[idx + 1],
-                sizeof(*list->devs) * (list->count - idx));
-    }
-
-    if (VIR_REALLOC_N(list->devs, list->count) < 0) {
-        ; /* not fatal */
-    }
-
+    VIR_DELETE_ELEMENT(list->devs, idx, list->count);
     return ret;
 }
 
diff --git a/src/util/virusb.c b/src/util/virusb.c
index 3bcb07c..103c301 100644
--- a/src/util/virusb.c
+++ b/src/util/virusb.c
@@ -60,7 +60,7 @@ struct _virUSBDevice {
 
 struct _virUSBDeviceList {
     virObjectLockable parent;
-    unsigned int count;
+    size_t count;
     virUSBDevicePtr *devs;
 };
 
@@ -451,11 +451,9 @@ virUSBDeviceListAdd(virUSBDeviceListPtr list,
         return -1;
     }
 
-    if (VIR_REALLOC_N(list->devs, list->count+1) < 0)
+    if (VIR_APPEND_ELEMENT(list->devs, list->count, dev, true) < 0)
         return -1;
 
-    list->devs[list->count++] = dev;
-
     return 0;
 }
 
@@ -484,22 +482,12 @@ virUSBDeviceListSteal(virUSBDeviceListPtr list,
     int i;
 
     for (i = 0; i < list->count; i++) {
-        if (list->devs[i]->bus != dev->bus ||
-            list->devs[i]->dev != dev->dev)
-            continue;
-
-        ret = list->devs[i];
-
-        if (i != list->count--)
-            memmove(&list->devs[i],
-                    &list->devs[i+1],
-                    sizeof(*list->devs) * (list->count - i));
-
-        if (VIR_REALLOC_N(list->devs, list->count) < 0) {
-            ; /* not fatal */
+        if (list->devs[i]->bus == dev->bus &&
+            list->devs[i]->dev == dev->dev) {
+            ret = list->devs[i];
+            VIR_DELETE_ELEMENT(list->devs, i, list->count);
+            break;
         }
-
-        break;
     }
     return ret;
 }
-- 
1.7.11.7