+static int meta_data_to_json (char *buffer, size_t buffer_size, /* {{{ */
+ meta_data_t *meta)
+{
+ size_t offset = 0;
+ char **keys = NULL;
+ int keys_num;
+ int status;
+ int i;
+
+ buffer[0] = 0;
+
+ if (meta == NULL)
+ return (EINVAL);
+
+#define BUFFER_ADD(...) do { \
+ status = ssnprintf (buffer + offset, buffer_size - offset, \
+ __VA_ARGS__); \
+ if (status < 1) \
+ return (-1); \
+ else if (((size_t) status) >= (buffer_size - offset)) \
+ return (-ENOMEM); \
+ else \
+ offset += ((size_t) status); \
+} while (0)
+
+ keys_num = meta_data_toc (meta, &keys);
+ if (keys_num == 0)
+ {
+ sfree (keys);
+ return (0);
+ }
+
+ for (i = 0; i < keys_num; ++i)
+ {
+ int type;
+ char *key = keys[i];
+
+ type = meta_data_type (meta, key);
+ if (type == MD_TYPE_STRING)
+ {
+ char *value = NULL;
+ if (meta_data_get_string (meta, key, &value) == 0)
+ {
+ char temp[512] = "";
+ json_escape_string (temp, sizeof (temp), value);
+ sfree (value);
+ BUFFER_ADD (",\"%s\":%s", key, temp);
+ }
+ }
+ else if (type == MD_TYPE_SIGNED_INT)
+ {
+ int64_t value = 0;
+ if (meta_data_get_signed_int (meta, key, &value) == 0)
+ BUFFER_ADD (",\"%s\":%"PRIi64, key, value);
+ }
+ else if (type == MD_TYPE_UNSIGNED_INT)
+ {
+ uint64_t value = 0;
+ if (meta_data_get_unsigned_int (meta, key, &value) == 0)
+ BUFFER_ADD (",\"%s\":%"PRIu64, key, value);
+ }
+ else if (type == MD_TYPE_DOUBLE)
+ {
+ double value = 0.0;
+ if (meta_data_get_double (meta, key, &value) == 0)
+ BUFFER_ADD (",\"%s\":%f", key, value);
+ }
+ else if (type == MD_TYPE_BOOLEAN)
+ {
+ _Bool value = 0;
+ if (meta_data_get_boolean (meta, key, &value) == 0)
+ BUFFER_ADD (",\"%s\":%s", key, value ? "true" : "false");
+ }
+
+ free (key);
+ } /* for (keys) */
+ free (keys);
+
+ if (offset <= 0)
+ return (ENOENT);
+
+ buffer[0] = '{'; /* replace leading ',' */
+ BUFFER_ADD ("}");
+
+#undef BUFFER_ADD
+
+ return (0);
+} /* }}} int meta_data_to_json */
+