From 344009bf26f53e0ba218401fa99eaad44cac33f1 Mon Sep 17 00:00:00 2001 From: jobol Date: Tue, 26 Jul 2016 19:22:25 +0200 Subject: [PATCH] Add method 'json_object_to_json_string_length' MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This new method allows to also get the length of the generated string. Fix #165 Change-Id: Iea91404027f143ca3d29a4c58d7c07ae53556110 Signed-off-by: José Bollo --- json_object.c | 33 ++++++++++++++++++++++++--------- json_object.h | 10 ++++++++++ 2 files changed, 34 insertions(+), 9 deletions(-) diff --git a/json_object.c b/json_object.c index 24cb7ab..29eb29d 100644 --- a/json_object.c +++ b/json_object.c @@ -295,20 +295,35 @@ void json_object_set_serializer(json_object *jso, /* extended conversion to string */ -const char* json_object_to_json_string_ext(struct json_object *jso, int flags) +const char* json_object_to_json_string_length(struct json_object *jso, int flags, size_t *length) { - if (!jso) - return "null"; + const char *r = NULL; + size_t s = 0; - if ((!jso->_pb) && !(jso->_pb = printbuf_new())) - return NULL; + if (!jso) + { + s = 4; + r = "null"; + } + else if ((jso->_pb) || (jso->_pb = printbuf_new())) + { + printbuf_reset(jso->_pb); - printbuf_reset(jso->_pb); + if(jso->_to_json_string(jso, jso->_pb, 0, flags) >= 0) + { + s = (size_t)jso->_pb->bpos; + r = jso->_pb->buf; + } + } - if(jso->_to_json_string(jso, jso->_pb, 0, flags) < 0) - return NULL; + if (length) + *length = s; + return r; +} - return jso->_pb->buf; +const char* json_object_to_json_string_ext(struct json_object *jso, int flags) +{ + return json_object_to_json_string_length(jso, flags, NULL); } /* backwards-compatible conversion to string */ diff --git a/json_object.h b/json_object.h index 4bcfcbc..19afa5e 100644 --- a/json_object.h +++ b/json_object.h @@ -223,6 +223,16 @@ extern const char* json_object_to_json_string(struct json_object *obj); extern const char* json_object_to_json_string_ext(struct json_object *obj, int flags); +/** Stringify object to json format + * @see json_object_to_json_string() for details on how to free string. + * @param obj the json_object instance + * @param flags formatting options, see JSON_C_TO_STRING_PRETTY and other constants + * @param length a pointer where, if not NULL, the length (without null) is stored + * @returns a string in JSON format and the length if not NULL + */ +extern const char* json_object_to_json_string_length(struct json_object *obj, int +flags, size_t *length); + /** * Returns the userdata set by json_object_set_userdata() or * json_object_set_serializer() -- 2.49.0