From b72bb6f1f44579118323fcd4c19349e6717d4b65 Mon Sep 17 00:00:00 2001
From: Eric Fischer <enf@pobox.com>
Date: Sat, 8 Feb 2014 09:30:02 -0800
Subject: [PATCH] Clean up after errors and fix related bugs:

It was freeing the wrong object when there was an error
attaching an object to its parent!

Don't crash when printing null (partially read) hash values.
---
 jsoncat.c  |  7 ++++++-
 jsonpull.c | 11 ++++++++---
 jsonpull.h |  1 +
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/jsoncat.c b/jsoncat.c
index 5ebd284..ad13d63 100644
--- a/jsoncat.c
+++ b/jsoncat.c
@@ -52,7 +52,10 @@ void json_print_one(json_object *j, int *depth) {
 }
 
 void json_print(json_object *j, int depth) {
-	if (j->type == JSON_HASH) {
+	if (j == NULL) {
+		// Hash value in incompletely read hash
+		printf("NULL");
+	} else if (j->type == JSON_HASH) {
 		printf("{\n");
 		indent(depth + 1);
 
@@ -123,7 +126,9 @@ void process_callback(FILE *f, char *fname) {
 	}
 
 	if (jp->error != NULL) {
+		fflush(stdout);
 		fprintf(stderr, "%s: %d: %s\n", fname, jp->line, jp->error);
+		json_free(jp->root);
 	}
 
 	json_end(jp);
diff --git a/jsonpull.c b/jsonpull.c
index e2ac071..09baf8c 100644
--- a/jsonpull.c
+++ b/jsonpull.c
@@ -5,12 +5,15 @@
 #include <stdarg.h>
 #include "jsonpull.h"
 
+#include "debug.h"
+
 json_pull *json_begin(int (*read)(struct json_pull *), int (*peek)(struct json_pull *), void *source) {
 	json_pull *j = malloc(sizeof(json_pull));
 
 	j->error = NULL;
 	j->line = 1;
 	j->container = NULL;
+	j->root = NULL;
 
 	j->read = read;
 	j->peek = peek;
@@ -97,7 +100,7 @@ static json_object *add_object(json_pull *j, json_type type) {
 				c->expect = JSON_COMMA;
 			} else {
 				j->error = "Expected a comma, not a list item";
-				free(c);
+				free(o);
 				return NULL;
 			}
 		} else if (c->type == JSON_HASH) {
@@ -107,7 +110,7 @@ static json_object *add_object(json_pull *j, json_type type) {
 			} else if (c->expect == JSON_KEY) {
 				if (type != JSON_STRING) {
 					j->error = "Hash key is not a string";
-					free(c);
+					free(o);
 					return NULL;
 				}
 
@@ -122,10 +125,12 @@ static json_object *add_object(json_pull *j, json_type type) {
 				c->expect = JSON_COLON;
 			} else {
 				j->error = "Expected a comma or colon";
-				free(c);
+				free(o);
 				return NULL;
 			}
 		}
+	} else {
+		j->root = o;
 	}
 
 	return o;
diff --git a/jsonpull.h b/jsonpull.h
index 64010f8..1a52f4c 100644
--- a/jsonpull.h
+++ b/jsonpull.h
@@ -33,6 +33,7 @@ typedef struct json_pull {
 	void *source;
 
 	json_object *container;
+	json_object *root;
 } json_pull;
 
 json_pull *json_begin_file(FILE *f);