[libvirt PATCHv2 01/15] util: json: introduce virJSONStringPrettifyBlanks
A horribly named function for unifying formatting when pretty-printing
empty JSON arrays and objects. Useful for having stable test output
even if different JSON libraries format these differently.
Signed-off-by: Ján Tomko <jtomko(a)redhat.com>
Reviewed-by: Peter Krempa <pkrempa(a)redhat.com>
---
src/libvirt_private.syms | 1 +
src/util/virjson.c | 34 ++++++++++++++++++++++++++++++++++
src/util/virjson.h | 2 ++
3 files changed, 37 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index af40e5dca3..d186dc40df 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -2612,6 +2612,7 @@ virISCSIScanTargets;
# util/virjson.h
+virJSONStringPrettifyBlanks;
virJSONStringReformat;
virJSONValueArrayAppend;
virJSONValueArrayAppendString;
diff --git a/src/util/virjson.c b/src/util/virjson.c
index 57707350da..0edf86cd1c 100644
--- a/src/util/virjson.c
+++ b/src/util/virjson.c
@@ -1861,6 +1861,40 @@ virJSONStringReformat(const char *jsonstr,
return virJSONValueToString(json, pretty);
}
+/**
+ * virJSONStringPrettifyBlanks:
+ * @jsonstr: string to prettify
+ *
+ * In the pretty mode of printing, various versions of JSON libraries
+ * format empty arrays and objects differently.
+ *
+ * Unify this to "[]" and "{}" which are used by json-c 0.17 and
newer.
+ * https://github.com/json-c/json-c/issues/778
+ *
+ * This format is also used by Python's 'json.dump' method.
+ *
+ * Returns the reformatted JSON string on success.
+ */
+char *virJSONStringPrettifyBlanks(const char *jsonstr)
+{
+ virBuffer buf = VIR_BUFFER_INITIALIZER;
+ const char *p;
+
+ for (p = jsonstr; *p && p[1]; p++) {
+ virBufferAddChar(&buf, *p);
+
+ if ((p[0] == '{' || p[0] == '[') && p[1] == '\n')
{
+ const char *q = p + 1;
+
+ virSkipSpaces(&q);
+
+ if (*q == '}' || *q == ']')
+ p = q - 1;
+ }
+ }
+
+ return virBufferContentAndReset(&buf);
+}
static virJSONValue *
virJSONValueObjectDeflattenKeys(virJSONValue *json);
diff --git a/src/util/virjson.h b/src/util/virjson.h
index e622798fe7..d8481e5890 100644
--- a/src/util/virjson.h
+++ b/src/util/virjson.h
@@ -271,6 +271,8 @@ virJSONValueCopy(const virJSONValue *in);
char *
virJSONStringReformat(const char *jsonstr,
bool pretty);
+char *
+virJSONStringPrettifyBlanks(const char *jsonstr);
virJSONValue *
virJSONValueObjectDeflatten(virJSONValue *json);
--
2.46.0