From 3ddf3a59112aa1723b0ff98c7d48b62b3ef641ef Mon Sep 17 00:00:00 2001
From: Dave Gamble <davegamble@gmail.com>
Date: Tue, 5 Feb 2013 17:14:12 +0000
Subject: [PATCH] stable solution for printing arrays - based on patch donated
 by Jerome Lang. Resolves issue in case malloc(0)!=0.

git-svn-id: http://svn.code.sf.net/p/cjson/code@44 e3330c51-1366-4df0-8b21-3ccf24e3d50e
---
 cJSON.c | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/cJSON.c b/cJSON.c
index 27c3385..027f440 100644
--- a/cJSON.c
+++ b/cJSON.c
@@ -327,25 +327,28 @@ static const char *parse_array(cJSON *item,const char *value)
 /* Render an array to text */
 static char *print_array(cJSON *item,int depth,int fmt)
 {
-	char **entries;
+	char **entries=0;
 	char *out=0,*ptr,*ret;int len=5;
 	cJSON *child=item->child;
 	int numentries=0,i=0,fail=0;
 	
 	/* How many entries in the array? */
 	while (child) numentries++,child=child->next;
-	/* Allocate an array to hold the values for each */
-	entries=(char**)cJSON_malloc(numentries*sizeof(char*));
-	if (!entries) return 0;
-	memset(entries,0,numentries*sizeof(char*));
-	/* Retrieve all the results: */
-	child=item->child;
-	while (child && !fail)
+	if (numentries)
 	{
-		ret=print_value(child,depth+1,fmt);
-		entries[i++]=ret;
-		if (ret) len+=strlen(ret)+2+(fmt?1:0); else fail=1;
-		child=child->next;
+		/* Allocate an array to hold the values for each */
+		entries=(char**)cJSON_malloc(numentries*sizeof(char*));
+		if (!entries) return 0;
+		memset(entries,0,numentries*sizeof(char*));
+		/* Retrieve all the results: */
+		child=item->child;
+		while (child && !fail)
+		{
+			ret=print_value(child,depth+1,fmt);
+			entries[i++]=ret;
+			if (ret) len+=strlen(ret)+2+(fmt?1:0); else fail=1;
+			child=child->next;
+		}
 	}
 	
 	/* If we didn't fail, try to malloc the output string */
@@ -357,7 +360,7 @@ static char *print_array(cJSON *item,int depth,int fmt)
 	if (fail)
 	{
 		for (i=0;i<numentries;i++) if (entries[i]) cJSON_free(entries[i]);
-		cJSON_free(entries);
+		if (entries) cJSON_free(entries);
 		return 0;
 	}
 	
@@ -370,7 +373,7 @@ static char *print_array(cJSON *item,int depth,int fmt)
 		if (i!=numentries-1) {*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;}
 		cJSON_free(entries[i]);
 	}
-	cJSON_free(entries);
+	if (entries) cJSON_free(entries);
 	*ptr++=']';*ptr++=0;
 	return out;	
 }