util: Introduce virStringListCopy

The API makes a deep copy of a NULL-terminated string list.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

src/util/virstring.c

@@ -239,6 +239,45 @@ virStringListRemove(char ***strings,
 }
 
 
+/**
+ * virStringListCopy:
+ * @dst: where to store the copy of @strings
+ * @src: a NULL-terminated array of strings
+ *
+ * Makes a deep copy of the @src string list and stores it in @dst. Callers
+ * are responsible for freeing @dst.
+ *
+ * Returns 0 on success, -1 on error.
+ */
+int
+virStringListCopy(char ***dst,
+                  const char **src)
+{
+    char **copy = NULL;
+    size_t i;
+
+    *dst = NULL;
+
+    if (!src)
+        return 0;
+
+    if (VIR_ALLOC_N(copy, virStringListLength(src) + 1) < 0)
+        goto error;
+
+    for (i = 0; src[i]; i++) {
+        if (VIR_STRDUP(copy[i], src[i]) < 0)
+            goto error;
+    }
+
+    *dst = copy;
+    return 0;
+
+ error:
+    virStringListFree(copy);
+    return -1;
+}
+
+
 /**
  * virStringListFree:
  * @str_array: a NULL-terminated array of strings to free

src/util/virstring.h

@@ -46,6 +46,9 @@ char **virStringListAdd(const char **strings,
 void virStringListRemove(char ***strings,
                          const char *item);
 
+int virStringListCopy(char ***dst,
+                      const char **src);
+
 void virStringListFree(char **strings);
 void virStringListFreeCount(char **strings,
                             size_t count);