[libvirt] [PATCH 05/12] util: json: add helper to iterate JSON object key=value pairs
This helper easies iterating all key=value pairs stored in a JSON
object. Usually we pick only certain known keys from a JSON object, but
this will allow to walk complete objects and have the callback act on
those.
---
src/libvirt_private.syms | 1 +
src/util/virjson.c | 33 +++++++++++++++++++++++++++++++++
src/util/virjson.h | 8 ++++++++
3 files changed, 42 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 70c81a8..196b837 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1548,6 +1548,7 @@ virJSONValueObjectAppendNumberUlong;
virJSONValueObjectAppendString;
virJSONValueObjectCreate;
virJSONValueObjectCreateVArgs;
+virJSONValueObjectForeachKeyValue;
virJSONValueObjectGet;
virJSONValueObjectGetBoolean;
virJSONValueObjectGetKey;
diff --git a/src/util/virjson.c b/src/util/virjson.c
index 3e00650..ec1778d 100644
--- a/src/util/virjson.c
+++ b/src/util/virjson.c
@@ -1198,6 +1198,39 @@ virJSONValueObjectIsNull(virJSONValuePtr object,
}
+/**
+ * virJSONValueObjectForeachKeyValue:
+ * @object: JSON object to iterate
+ * @cb: callback to call on key-value pairs contained in the object
+ * @opaque: generic data for the callback
+ *
+ * Iterates all key=value pairs in @object. Iteration breaks if @cb returns
+ * negative value.
+ *
+ * Returns 0 if all elements were iterated, -2 if @cb returned negative value
+ * during iteration and -1 on generic errors.
+ */
+int
+virJSONValueObjectForeachKeyValue(virJSONValuePtr object,
+ virJSONValueObjectIteratorFunc cb,
+ void *opaque)
+{
+ size_t i;
+
+ if (object->type != VIR_JSON_TYPE_OBJECT)
+ return -1;
+
+ for (i = 0; i < object->data.object.npairs; i++) {
+ virJSONObjectPairPtr elem = object->data.object.pairs + i;
+
+ if (cb(elem->key, elem->value, opaque) < 0)
+ return -2;
+ }
+
+ return 0;
+}
+
+
#if WITH_YAJL
static int
virJSONParserInsertValue(virJSONParserPtr parser,
diff --git a/src/util/virjson.h b/src/util/virjson.h
index 57010b0..9bb7461 100644
--- a/src/util/virjson.h
+++ b/src/util/virjson.h
@@ -157,4 +157,12 @@ virJSONValuePtr virJSONValueFromString(const char *jsonstring);
char *virJSONValueToString(virJSONValuePtr object,
bool pretty);
+typedef int (*virJSONValueObjectIteratorFunc)(const char *key,
+ const virJSONValue *value,
+ void *opaque);
+
+int virJSONValueObjectForeachKeyValue(virJSONValuePtr object,
+ virJSONValueObjectIteratorFunc cb,
+ void *opaque);
+
#endif /* __VIR_JSON_H_ */
--
2.2.2