Views: implemented handling of JSON formatted comments

src/obiview.h

@@ -59,6 +59,8 @@
                                 	             */
 #define ID_PREFIX "seq"						    /**< The default prefix of sequence identifiers in automatic ID columns.
                                 	 	  	  	 */
+#define PREDICATE_KEY "predicates"		        /**< The key used in the json-formatted view comments to store predicates.
+                                	 	  	  	 */
 
 
 /**
@@ -484,6 +486,44 @@ OBIDMS_column_p* obi_view_get_pointer_on_column_in_view(Obiview_p view, const ch
 int obi_view_create_column_alias(Obiview_p view, const char* current_name, const char* alias);
 
 
+/**
+ * @brief Internal function writing new comments in a view file.
+ *
+ * The new comments replace the pre-existing ones.
+ * The view file is enlarged if necessary.
+ *
+ * @param view A pointer on the view.
+ * @param comments The new comments that should be written.
+ *
+ * @retval 0 if the operation was successfully completed.
+ * @retval -1 if an error occurred.
+ *
+ * @since August 2016
+ * @author Celine Mercier (celine.mercier@metabarcoding.org)
+ */
+int obi_view_write_comments(Obiview_p view, const char* comments);
+
+
+/**
+ * @brief Adds comments to a view file.
+ *
+ * This reads the comments in the JSON format and adds the key value pair.
+ * If the key already exists, the value format is turned into an array and the new value is appended
+ * if it is not already in the array.
+ *
+ * @param column A pointer on an OBIDMS column.
+ * @param key The key.
+ * @param value The value associated with the key.
+ *
+ * @retval 0 if the operation was successfully completed.
+ * @retval -1 if an error occurred.
+ *
+ * @since August 2018
+ * @author Celine Mercier (celine.mercier@metabarcoding.org)
+ */
+int obi_view_add_comment(Obiview_p view, const char* key, const char* value);
+
+
 /**
  * @brief Closes an opened view, and saves it if it is not read-only (meaning it is not already saved in the view file).
  *