libxl: introduce flexarray_append_pair

Introduce flexarray_append_pair: a simple syntactic sugar to add a pair
of pointers to a flexarray, very useful when adding pairs of strings to
xenstore.

Replace flexarray_vappend calls (and one pair of flexarray_append)
with flexarray_append_pair calls when dealing with flexarrays that are
going to be used with libxl__xs_kvs_of_flexarray:

NULL is a valid pointer value in these cases while flexarray_vappend
uses NULL as vargs terminator, so the old code is buggy.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/tools/libxl/flexarray.c b/tools/libxl/flexarray.c
index 724eabd52f..c89c23e159 100644
--- a/tools/libxl/flexarray.c
+++ b/tools/libxl/flexarray.c
@@ -69,6 +69,14 @@ int flexarray_append(flexarray_t *array, void *ptr)
     return flexarray_set(array, array->count, ptr);
 }
 
+int flexarray_append_pair(flexarray_t *array, void *ptr1, void *ptr2)
+{
+    int rc = flexarray_append(array, ptr1);
+    if (!rc)
+        rc = flexarray_append(array, ptr2);
+    return rc;
+}
+
 int flexarray_vappend(flexarray_t *array, ...)
 {
     va_list va;