feat: new (debug) function json_printf_pretty

Signed-off-by: Davide Madrisan <[email protected]>

include/json_helpers.h

@@ -28,6 +28,7 @@ extern "C"
   int json_token_streq (const char *json, jsmntok_t * tok, const char *s);
   char *json_token_tostr (char *json, jsmntok_t * t);
   jsmntok_t *json_tokenise (const char *json, size_t *ntoken);
+  void json_printf_pretty (const char *json, char **dump, int indent);
 
 #ifdef __cplusplus
 }

lib/json_helpers.c

@@ -19,15 +19,17 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <assert.h>
+#include <stdlib.h>
 #include <string.h>
 
 #include "jsmn.h"
 #include "json_helpers.h"
 #include "logging.h"
+#include "system.h"
 #include "xalloc.h"
 
 int
-json_token_streq (const char *json, jsmntok_t * tok, const char *s)
+json_token_streq (const char *json, jsmntok_t *tok, const char *s)
 {
   if (tok->type == JSMN_STRING && (int) strlen (s) == tok->end - tok->start &&
       strncmp (json + tok->start, s, tok->end - tok->start) == 0)
@@ -37,7 +39,7 @@ json_token_streq (const char *json, jsmntok_t * tok, const char *s)
 }
 
 char *
-json_token_tostr (char *json, jsmntok_t * t)
+json_token_tostr (char *json, jsmntok_t *t)
 {
   return xsubstrdup (json + t->start, t->end - t->start);
 }
@@ -65,3 +67,79 @@ json_tokenise (const char *json, size_t *ntoken)
   *ntoken = r;
   return tokens;
 }
+
+static int
+json_dump (const char *json, jsmntok_t *t, size_t count, int indent,
+	   FILE *stream)
+{
+  int i, j, k;
+
+  if (t->type == JSMN_PRIMITIVE)
+    {
+      fprintf (stream, "%.*s", t->end - t->start, json + t->start);
+      if (t->size == 0)
+	fprintf (stream, "\n");
+      return 1;
+    }
+  else if (t->type == JSMN_STRING)
+    {
+      fprintf (stream, "%.*s", t->end - t->start, json + t->start);
+      if (t->size == 0)
+	fprintf (stream, "\n");
+      return 1;
+    }
+  else if (t->type == JSMN_OBJECT)
+    {
+      j = 0;
+      jsmntok_t *token;
+
+      fprintf (stream, "\n");
+
+      for (i = 0; i < t->size; i++)
+	{
+	  for (k = 0; k < indent; k++)
+	    fprintf (stream, "  ");
+
+	  token = t + 1 + j;
+	  j += json_dump (json, token, count - j, indent + 1, stream);
+
+	  /* get the value of the previous JSON label */
+	  if (token->size > 0)
+	    {
+	      fprintf (stream, ": ");
+	      j += json_dump (json, t + 1 + j, count - j, indent + 1, stream);
+	    }
+	}
+      return j + 1;
+    }
+  else if (t->type == JSMN_ARRAY)
+    {
+      j = 0;
+      fprintf (stream, "\n");
+
+      for (i = 0; i < t->size; i++)
+	{
+	  for (k = 0; k < indent - 1; k++)
+	    fprintf (stream, "  ");
+
+	  fprintf (stream, "  - ");
+	  j += json_dump (json, t + 1 + j, count - j, indent + 1, stream);
+	}
+
+      return j + 1;
+    }
+
+  return 0;
+}
+
+void
+json_printf_pretty (const char *json, char **dump, int indent)
+{
+  size_t ntoken, size;
+  FILE *stream = open_memstream (dump, &size);
+
+  jsmntok_t *tok = json_tokenise (json, &ntoken);
+  json_dump (json, tok, tok->size, indent, stream);
+
+  fclose (stream);
+}