From 29598e3dc850c2edf721704bf00f6a825077ff6e Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Fri, 4 Feb 2011 21:57:59 +0100
Subject: [PATCH] add functions for allocating and adding a string buffer field

---
 blobmsg.c | 31 +++++++++++++++++++++++++++++++
 blobmsg.h |  3 +++
 2 files changed, 34 insertions(+)

diff --git a/blobmsg.c b/blobmsg.c
index e5de129..ed7a880 100644
--- a/blobmsg.c
+++ b/blobmsg.c
@@ -310,6 +310,37 @@ blobmsg_open_nested(struct blob_buf *buf, const char *name, bool array)
 	return (void *)offset;
 }
 
+void *
+blobmsg_alloc_string_buffer(struct blob_buf *buf, const char *name, int maxlen)
+{
+	struct blob_attr *attr;
+	void *data_dest;
+
+	attr = blobmsg_new(buf, BLOBMSG_TYPE_STRING, name, maxlen, &data_dest);
+	if (!attr)
+		return NULL;
+
+	data_dest = blobmsg_data(attr);
+	blob_set_raw_len(buf->head, blob_pad_len(buf->head) - blob_raw_len(attr));
+	blob_set_raw_len(attr, blob_raw_len(attr) - maxlen);
+
+	return data_dest;
+}
+
+void
+blobmsg_add_string_buffer(struct blob_buf *buf)
+{
+	struct blob_attr *attr;
+	int len, attrlen;
+
+	attr = blob_next(buf->head);
+	len = strlen(blobmsg_data(attr)) + 1;
+
+	attrlen = blob_raw_len(attr) + len;
+	blob_set_raw_len(attr, attrlen);
+	blob_set_raw_len(buf->head, blob_raw_len(buf->head) + attrlen);
+}
+
 int
 blobmsg_add_field(struct blob_buf *buf, int type, const char *name,
                   const void *data, int len)
diff --git a/blobmsg.h b/blobmsg.h
index e978235..dce5b85 100644
--- a/blobmsg.h
+++ b/blobmsg.h
@@ -139,6 +139,9 @@ static inline int blobmsg_buf_init(struct blob_buf *buf)
 	return blob_buf_init(buf, BLOBMSG_TYPE_TABLE);
 }
 
+void *blobmsg_alloc_string_buffer(struct blob_buf *buf, const char *name, int maxlen);
+void blobmsg_add_string_buffer(struct blob_buf *buf);
+
 char *blobmsg_format_json(struct blob_attr *attr, bool list);
 
 #define blobmsg_for_each_attr(pos, attr, rem) \