From: Eric Haszlakiewicz <erh+git@nimenees.com>
Date: Fri, 25 Aug 2017 05:15:39 +0000 (-0400)
Subject: PR#331: for Visual Studio, use a snprintf/vsnprintf wrapper that ensures the string... 
X-Git-Tag: json-c-0.13-20171207~62
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=81f6edbfd579214b3e337885b5148c3931780365;p=json-c

PR#331: for Visual Studio, use a snprintf/vsnprintf wrapper that ensures the string is terminated.
---

diff --git a/json_object.c b/json_object.c
index 7148731..a317123 100644
--- a/json_object.c
+++ b/json_object.c
@@ -31,13 +31,7 @@
 #include "json_util.h"
 #include "math_compat.h"
 #include "strdup_compat.h"
-
-#if !defined(HAVE_SNPRINTF) && defined(_MSC_VER)
-  /* MSC has the version as _snprintf */
-# define snprintf _snprintf
-#elif !defined(HAVE_SNPRINTF)
-# error You do not have snprintf on your system.
-#endif /* HAVE_SNPRINTF */
+#include "snprintf_compat.h"
 
 // Don't define this.  It's not thread-safe.
 /* #define REFCOUNT_DEBUG 1 */
diff --git a/json_util.c b/json_util.c
index cc57e34..2121150 100644
--- a/json_util.c
+++ b/json_util.c
@@ -48,12 +48,7 @@
 # define open _open
 #endif
 
-#if !defined(HAVE_SNPRINTF) && defined(_MSC_VER)
-  /* MSC has the version as _snprintf */
-# define snprintf _snprintf
-#elif !defined(HAVE_SNPRINTF)
-# error You do not have snprintf on your system.
-#endif /* HAVE_SNPRINTF */
+#include "snprintf_compat.h"
 
 #include "debug.h"
 #include "printbuf.h"
diff --git a/printbuf.c b/printbuf.c
index 2745339..6c77b5d 100644
--- a/printbuf.c
+++ b/printbuf.c
@@ -27,6 +27,7 @@
 
 #include "debug.h"
 #include "printbuf.h"
+#include "snprintf_compat.h"
 #include "vasprintf_compat.h"
 
 static int printbuf_extend(struct printbuf *p, int min_size);
diff --git a/snprintf_compat.h b/snprintf_compat.h
new file mode 100644
index 0000000..7323aaa
--- /dev/null
+++ b/snprintf_compat.h
@@ -0,0 +1,36 @@
+#ifndef __snprintf_compat_h
+#define __snprintf_compat_h
+
+/*
+ * Microsoft's _vsnprintf and _snprint don't always terminate
+ * the string, so use wrappers that ensure that.
+ */
+
+#include <stdarg.h>
+
+#if !defined(HAVE_SNPRINTF) && defined(_MSC_VER)
+static int json_c_vsnprintf(char *str, size_t size, const char *format, va_list ap)
+{
+	int ret;
+	ret = _vsnprintf(str, size, format, ap);
+	str[size - 1] = '\0';
+	return ret;
+}
+#define vsnprintf json_c_vsnprintf
+
+static int json_c_snprintf(char *str, size_t size, const char *format, ...)
+{
+	va_list ap;
+	int ret;
+	va_start(ap, format);
+	ret = json_c_vsnprintf(str, size, format, ap);
+	va_end(ap);
+	return ret;
+}
+#define snprintf json_c_snprintf
+
+#elif !defined(HAVE_SNPRINTF) /* !HAVE_SNPRINTF */
+# error Need vsnprintf!
+#endif /* !HAVE_SNPRINTF && defined(WIN32) */
+
+#endif /* __snprintf_compat_h */
diff --git a/tests/test_locale.c b/tests/test_locale.c
index a3e319d..7d6541a 100644
--- a/tests/test_locale.c
+++ b/tests/test_locale.c
@@ -7,6 +7,7 @@
 #include "config.h"
 #include "json.h"
 #include "json_tokener.h"
+#include "snprintf_compat.h"
 
 #ifdef HAVE_LOCALE_H
 #include <locale.h>
diff --git a/vasprintf_compat.h b/vasprintf_compat.h
index 51e234b..40ff550 100644
--- a/vasprintf_compat.h
+++ b/vasprintf_compat.h
@@ -1,11 +1,7 @@
 #ifndef __vasprintf_compat_h
 #define __vasprintf_compat_h
 
-#if !defined(HAVE_VSNPRINTF) && defined(_MSC_VER)
-# define vsnprintf _vsnprintf
-#elif !defined(HAVE_VSNPRINTF) /* !HAVE_VSNPRINTF */
-# error Need vsnprintf!
-#endif /* !HAVE_VSNPRINTF && defined(WIN32) */
+#include "snprintf_compat.h"
 
 #if !defined(HAVE_VASPRINTF)
 /* CAW: compliant version of vasprintf */