blobmsg: fix dynamic string buffer length calculation

[project/libubox.git] / blobmsg.c

diff --git a/blobmsg.c b/blobmsg.c
index bdc5ef7..a77f158 100644 (file)
--- a/blobmsg.c
+++ b/blobmsg.c
@@ -21,7 +21,7 @@ struct strbuf {
        char *buf;
 };
 
-static bool blobmsg_puts(struct strbuf *s, char *c, int len)
+static bool blobmsg_puts(struct strbuf *s, const char *c, int len)
 {
        if (len <= 0)
                return true;
@@ -37,9 +37,9 @@ static bool blobmsg_puts(struct strbuf *s, char *c, int len)
        return true;
 }
 
-static void blobmsg_format_string(struct strbuf *s, char *str)
+static void blobmsg_format_string(struct strbuf *s, const char *str)
 {
-       char *p, *last = str, *end = str + strlen(str);
+       const char *p, *last = str, *end = str + strlen(str);
        char buf[8] = "\\u00";
 
        blobmsg_puts(s, "\"", 1);
@@ -100,7 +100,7 @@ static void blobmsg_format_element(struct strbuf *s, struct blob_attr *attr, boo
        void *data;
        int len;
 
-       if (!array) {
+       if (!array && blobmsg_name(attr)[0]) {
                blobmsg_format_string(s, blobmsg_name(attr));
                blobmsg_puts(s, ":", 1);
        }
@@ -126,7 +126,7 @@ static void blobmsg_format_element(struct strbuf *s, struct blob_attr *attr, boo
                sprintf(buf, "%lld", *(uint64_t *)data);
                break;
        case BLOBMSG_TYPE_STRING:
-               blobmsg_puts(s, data, strlen(data));
+               blobmsg_format_string(s, data);
                return;
        case BLOBMSG_TYPE_ARRAY:
                blobmsg_format_json_list(s, data, len, true);
@@ -155,7 +155,7 @@ static void blobmsg_format_json_list(struct strbuf *s, struct blob_attr *attr, i
        blobmsg_puts(s, (array ? " ]" : " }"), 2);
 }
 
-char *blobmsg_format_json(struct blob_attr *attr)
+char *blobmsg_format_json(struct blob_attr *attr, bool list)
 {
        struct strbuf s;
 
@@ -163,7 +163,10 @@ char *blobmsg_format_json(struct blob_attr *attr)
        s.buf = malloc(s.len);
        s.pos = 0;
 
-       blobmsg_format_element(&s, attr, true, true);
+       if (list)
+               blobmsg_format_json_list(&s, blob_data(attr), blob_len(attr), false);
+       else
+               blobmsg_format_element(&s, attr, false, false);
 
        if (!s.len)
                return NULL;
@@ -172,9 +175,19 @@ char *blobmsg_format_json(struct blob_attr *attr)
        return s.buf;
 }
 
+static const int blob_type[__BLOBMSG_TYPE_LAST] = {
+       [BLOBMSG_TYPE_INT8] = BLOB_ATTR_INT8,
+       [BLOBMSG_TYPE_INT16] = BLOB_ATTR_INT16,
+       [BLOBMSG_TYPE_INT32] = BLOB_ATTR_INT32,
+       [BLOBMSG_TYPE_INT64] = BLOB_ATTR_INT64,
+       [BLOBMSG_TYPE_STRING] = BLOB_ATTR_STRING,
+};
+
 bool blobmsg_check_attr(const struct blob_attr *attr, bool name)
 {
        const struct blobmsg_hdr *hdr;
+       const char *data;
+       int id, len;
 
        if (blob_len(attr) < sizeof(struct blobmsg_hdr))
                return false;
@@ -189,7 +202,17 @@ bool blobmsg_check_attr(const struct blob_attr *attr, bool name)
        if (hdr->name[hdr->namelen] != 0)
                return false;
 
-       return true;
+       id = blob_id(attr);
+       len = blobmsg_data_len(attr);
+       data = blobmsg_data(attr);
+
+       if (!id || id > BLOBMSG_TYPE_LAST)
+               return false;
+
+       if (!blob_type[id])
+               return true;
+
+       return blob_check_type(data, len, blob_type[id]);
 }
 
 int blobmsg_parse(const struct blobmsg_policy *policy, int policy_len,
@@ -287,6 +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_pad_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) + blob_pad_len(attr));
+}
+
 int
 blobmsg_add_field(struct blob_buf *buf, int type, const char *name,
                   const void *data, int len)