[libvirt] [PATCH 3/9] util: Move JSON object deflattening code to json utility file

[Peter Krempa]

The code will become more universal so it makes more sense for it to
live with the rest of the JSON functions.
---
 src/libvirt_private.syms  |  1 +
 src/util/virjson.c        | 61 ++++++++++++++++++++++++++++++++++++++++++++
 src/util/virjson.h        |  2 ++
 src/util/virstoragefile.c | 65 +----------------------------------------------
 4 files changed, 65 insertions(+), 64 deletions(-)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index d487b1f43..9f64b8d93 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1931,6 +1931,7 @@ virJSONValueObjectAppendNumberUlong;
 virJSONValueObjectAppendString;
 virJSONValueObjectCreate;
 virJSONValueObjectCreateVArgs;
+virJSONValueObjectDeflatten;
 virJSONValueObjectForeachKeyValue;
 virJSONValueObjectGet;
 virJSONValueObjectGetArray;
diff --git a/src/util/virjson.c b/src/util/virjson.c
index efd6c3a0e..8ab542432 100644
--- a/src/util/virjson.c
+++ b/src/util/virjson.c
@@ -1965,3 +1965,64 @@ virJSONStringReformat(const char *jsonstr,
     virJSONValueFree(json);
     return ret;
 }
+
+
+static int
+virJSONValueObjectDeflattenWorker(const char *key,
+                                  virJSONValuePtr value,
+                                  void *opaque)
+{
+    virJSONValuePtr retobj = opaque;
+    virJSONValuePtr newval = NULL;
+    const char *newkey;
+
+    if (!(newkey = STRSKIP(key, "file."))) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("JSON object is neither nested nor flattened"));
+        return -1;
+    }
+
+    if (!(newval = virJSONValueCopy(value)))
+        return -1;
+
+    if (virJSONValueObjectAppend(retobj, newkey, newval) < 0) {
+        virJSONValueFree(newval);
+        return -1;
+    }
+
+    return 0;
+}
+
+
+/**
+ * virJSONValueObjectDeflatten:
+ *
+ * In some cases it's possible to nest JSON objects by prefixing object members
+ * with the parent object name followed by the dot and then the attribute name
+ * rather than directly using a nested value object (e.g qemu's JSON
+ * pseudo-protocol in backing file definition).
+ *
+ * This function will attempt to reverse the process and provide a nested json
+ * hierarchy so that the parsers can be kept simple and we still can use the
+ * weird syntax some users might use.
+ *
+ * Currently this function will flatten out just the 'file.' prefix into a new
+ * tree. Any other syntax will be rejected.
+ */
+virJSONValuePtr
+virJSONValueObjectDeflatten(virJSONValuePtr json)
+{
+    virJSONValuePtr ret;
+
+    if (!(ret = virJSONValueNewObject()))
+        return NULL;
+
+    if (virJSONValueObjectForeachKeyValue(json,
+                                          virJSONValueObjectDeflattenWorker,
+                                          ret) < 0) {
+        virJSONValueFree(ret);
+        return NULL;
+    }
+
+    return ret;
+}
diff --git a/src/util/virjson.h b/src/util/virjson.h
index c9d9752de..e89a776ab 100644
--- a/src/util/virjson.h
+++ b/src/util/virjson.h
@@ -186,4 +186,6 @@ virJSONValuePtr virJSONValueCopy(const virJSONValue *in);

 char *virJSONStringReformat(const char *jsonstr, bool pretty);

+virJSONValuePtr virJSONValueObjectDeflatten(virJSONValuePtr json);
+
 #endif /* __VIR_JSON_H_ */
diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c
index f0ed5c6bd..52c5301ff 100644
--- a/src/util/virstoragefile.c
+++ b/src/util/virstoragefile.c
@@ -3244,69 +3244,6 @@ static const struct virStorageSourceJSONDriverParser jsonParsers[] = {
 };


-static int
-virStorageSourceParseBackingJSONDeflattenWorker(const char *key,
-                                                virJSONValuePtr value,
-                                                void *opaque)
-{
-    virJSONValuePtr retobj = opaque;
-    virJSONValuePtr newval = NULL;
-    const char *newkey;
-
-    if (!(newkey = STRSKIP(key, "file."))) {
-        virReportError(VIR_ERR_INVALID_ARG, "%s",
-                       _("JSON backing file syntax is neither nested nor "
-                         "flattened"));
-        return -1;
-    }
-
-    if (!(newval = virJSONValueCopy(value)))
-        return -1;
-
-    if (virJSONValueObjectAppend(retobj, newkey, newval) < 0) {
-        virJSONValueFree(newval);
-        return -1;
-    }
-
-    return 0;
-}
-
-
-/**
- * virStorageSourceParseBackingJSONDeflatten:
- *
- * The json: pseudo-protocol syntax in qemu allows multiple approaches to
- * describe nesting of the values. This is due to the lax handling of the string
- * in qemu and the fact that internally qemu is flattening the values using '.'.
- *
- * This allows to specify nested json strings either using nested json objects
- * or prefixing object members with the parent object name followed by the dot.
- *
- * This function will attempt to reverse the process and provide a nested json
- * hierarchy so that the parsers can be kept simple and we still can use the
- * weird syntax some users might use.
- *
- * Currently this function will flatten out just the 'file.' prefix into a new
- * tree. Any other syntax will be rejected.
- */
-static virJSONValuePtr
-virStorageSourceParseBackingJSONDeflatten(virJSONValuePtr json)
-{
-    virJSONValuePtr ret;
-
-    if (!(ret = virJSONValueNewObject()))
-        return NULL;
-
-    if (virJSONValueObjectForeachKeyValue(json,
-                                          virStorageSourceParseBackingJSONDeflattenWorker,
-                                          ret) < 0) {
-        virJSONValueFree(ret);
-        return NULL;
-    }
-
-    return ret;
-}
-

 static int
 virStorageSourceParseBackingJSONInternal(virStorageSourcePtr src,
@@ -3320,7 +3257,7 @@ virStorageSourceParseBackingJSONInternal(virStorageSourcePtr src,
     int ret = -1;

     if (!(file = virJSONValueObjectGetObject(json, "file"))) {
-        if (!(fixedroot = virStorageSourceParseBackingJSONDeflatten(json)))
+        if (!(fixedroot = virJSONValueObjectDeflatten(json)))
             goto cleanup;

         file = fixedroot;
-- 
2.12.2