virTypedParamsGetStringList: Refactor and adjust docs

Use automatic freeing, declare one variable per line and return early
when possible. As this is an internal helper there's no need to check
that the caller passed non-NULL @values.

Modify the documentation to be accurate and warn callers to not free the
strings just the array.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>

diff --git a/src/util/virtypedparam.c b/src/util/virtypedparam.c
index 634385aa977a21798d1dafdacf40baa9a01523a7..86fbaf5e9d4f2eb667d4a99cb6cec7753eb6d394 100644 (file)
--- a/src/util/virtypedparam.c
+++ b/src/util/virtypedparam.c
@@ -432,13 +432,13 @@ virTypedParamsFilter(virTypedParameterPtr params,
  * @values: array of returned values
  *
  * Finds all parameters with desired @name within @params and
- * store their values into @values. The @values array is self
- * allocated and its length is stored into @picked. When no
- * longer needed, caller should free the returned array, but not
- * the items since they are taken from @params array.
+ * store their values into @values.
  *
- * Returns amount of strings in @values array on success,
- * -1 otherwise.
+ * Important: The strings in the returned string list @values are borrowed from
+ * @params and thus caller must free only the pointer returned as @values, but
+ * not the contents.
+ *
+ * Returns amount of strings in @values array on success.
  */
 int
 virTypedParamsGetStringList(virTypedParameterPtr params,
@@ -446,31 +446,26 @@ virTypedParamsGetStringList(virTypedParameterPtr params,
                             const char *name,
                             const char ***values)
 {
-    size_t i, n;
+    size_t i;
+    size_t n = 0;
     size_t nfiltered;
-    virTypedParameterPtr *filtered = NULL;
+    g_autofree virTypedParameterPtr *filtered = NULL;
 
-    virCheckNonNullArgGoto(values, error);
     *values = NULL;
 
     nfiltered = virTypedParamsFilter(params, nparams, name, &filtered);
 
-    if (nfiltered)
-        *values = g_new0(const char *, nfiltered);
+    if (nfiltered == 0)
+        return 0;
+
+    *values = g_new0(const char *, nfiltered);
 
-    for (n = 0, i = 0; i < nfiltered; i++) {
+    for (i = 0; i < nfiltered; i++) {
         if (filtered[i]->type == VIR_TYPED_PARAM_STRING)
             (*values)[n++] = filtered[i]->value.s;
     }
 
-    VIR_FREE(filtered);
     return n;
-
- error:
-    if (values)
-        VIR_FREE(*values);
-    VIR_FREE(filtered);
-    return -1;
 }