From 42bf1afa5a06926839fb4ccf0bab27aa1a956bae Mon Sep 17 00:00:00 2001
From: Eric Kinzie <ekinzie@labn.net>
Date: Fri, 2 Sep 2022 16:33:21 +0200
Subject: [PATCH] lib: convert termtable to json

Add a function that returns a JSON-C structure containing a representation
of a termtable.  This is intended to be a quick way to implement JSON
output to CLI commands.

Signed-off-by: Eric Kinzie <ekinzie@labn.net>
---
 lib/termtable.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 lib/termtable.h | 12 ++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/lib/termtable.c b/lib/termtable.c
index 30f1ab74c6..9b36d5ebfa 100644
--- a/lib/termtable.c
+++ b/lib/termtable.c
@@ -7,6 +7,7 @@
 #include <zebra.h>
 #include <stdio.h>
 
+#include "lib/json.h"
 #include "printfrr.h"
 #include "memory.h"
 #include "termtable.h"
@@ -485,3 +486,45 @@ char *ttable_dump(struct ttable *tt, const char *newline)
 
 	return buf;
 }
+
+/* Crude conversion from ttable to json array.
+ * Assume that the first row has column headings.
+ *
+ * Formats are:
+ *   d	int32
+ *   f	double
+ *   l	int64
+ *   s	string (default)
+ */
+json_object *ttable_json(struct ttable *tt, const char *const formats)
+{
+	struct ttable_cell *row; /* iteration pointers */
+	json_object *json = NULL;
+
+	json = json_object_new_array();
+
+	for (int i = 1; i < tt->nrows; i++) {
+		json_object *jobj;
+		json_object *val;
+
+		row = tt->table[i];
+		jobj = json_object_new_object();
+		json_object_array_add(json, jobj);
+		for (int j = 0; j < tt->ncols; j++) {
+			switch (formats[j]) {
+			case 'd':
+			case 'l':
+				val = json_object_new_int64(atol(row[j].text));
+				break;
+			case 'f':
+				val = json_object_new_double(atof(row[j].text));
+				break;
+			default:
+				val = json_object_new_string(row[j].text);
+			}
+			json_object_object_add(jobj, tt->table[0][j].text, val);
+		}
+	}
+
+	return json;
+}
diff --git a/lib/termtable.h b/lib/termtable.h
index 3aa8caee89..7258682bd8 100644
--- a/lib/termtable.h
+++ b/lib/termtable.h
@@ -8,6 +8,7 @@
 #define _TERMTABLE_H_
 
 #include <zebra.h>
+#include "lib/json.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -277,6 +278,17 @@ void ttable_rowseps(struct ttable *tt, unsigned int row,
  */
 char *ttable_dump(struct ttable *tt, const char *newline);
 
+/**
+ * Convert a table to a JSON array of objects.
+ *
+ * Caller must free the returned json_object structure.
+ *
+ * @param tt the table to convert
+ * @param formats an array of characters indicating what JSON type should be
+ * used.
+ */
+json_object *ttable_json(struct ttable *tt, const char *const formats);
+
 #ifdef __cplusplus
 }
 #endif