From fbe329bb701e855131be9bc093a048d8f4dd4944 Mon Sep 17 00:00:00 2001
From: Tsuda Kageyu <tsuda.kageyu@gmail.com>
Date: Wed, 1 May 2013 14:54:17 +0900
Subject: [PATCH] Use snprintf instead of sprintf if possible.

---
 ConfigureChecks.cmake  | 14 +++++++++-
 config-taglib.h.cmake  |  4 +++
 taglib/mp4/mp4item.cpp | 59 ++++++++++++++++++++++++++++--------------
 3 files changed, 56 insertions(+), 21 deletions(-)

diff --git a/ConfigureChecks.cmake b/ConfigureChecks.cmake
index c08f7377..42144de7 100644
--- a/ConfigureChecks.cmake
+++ b/ConfigureChecks.cmake
@@ -84,13 +84,25 @@ if(NOT HAVE_STD_SHARED_PTR AND NOT HAVE_TR1_SHARED_PTR AND NOT HAVE_BOOST_SHARED
   endif()
 endif()
 
-
 # Determine whether your compiler supports codecvt header.
 check_cxx_source_compiles("
 #include <codecvt>
 int main() { std::codecvt_utf8_utf16<wchar_t> x; return 0; }
 " HAVE_CODECVT)
 
+# Determine whether your compiler supports some safer version of sprintf.
+check_cxx_source_compiles("
+  #include <cstdio>
+  int main() { char buf[20]; snprintf(buf, 20, \"%d\", 1); return 0; }
+" HAVE_SNPRINTF)
+
+if(NOT HAVE_SNPRINTF)
+  check_cxx_source_compiles("
+    #include <cstdio>
+    int main() { char buf[20]; sprintf_s(buf, \"%d\", 1);  return 0; }
+  " HAVE_SPRINTF_S)
+endif()
+
 # check for libz using the cmake supplied FindZLIB.cmake
 find_package(ZLIB)
 if(ZLIB_FOUND)
diff --git a/config-taglib.h.cmake b/config-taglib.h.cmake
index 6d48cbf0..1e0adb37 100644
--- a/config-taglib.h.cmake
+++ b/config-taglib.h.cmake
@@ -14,6 +14,10 @@
 #cmakedefine   HAVE_WIN_ATOMIC 1
 #cmakedefine   HAVE_IA64_ATOMIC 1
 
+/* Defined if your compiler supports some safer version of sprintf */
+#cmakedefine   HAVE_SNPRINTF 1
+#cmakedefine   HAVE_SPRINTF_S 1
+
 /* Defined if your compiler has <codecvt> header */
 #cmakedefine   HAVE_CODECVT 1
 
diff --git a/taglib/mp4/mp4item.cpp b/taglib/mp4/mp4item.cpp
index 6c1f3c40..65f45546 100644
--- a/taglib/mp4/mp4item.cpp
+++ b/taglib/mp4/mp4item.cpp
@@ -27,19 +27,44 @@
 # include <config.h>
 #endif
 
-#include <stdio.h>
+#include <cstdarg>
+#include <cstdio>
 
 #include <taglib.h>
 #include <tdebug.h>
 #include "mp4item.h"
 
-#if defined(_MSC_VER) && (_MSC_VER >= 1400)  // VC++2005 or later
-# define SPRINTF sprintf_s
+using namespace TagLib;
+
+namespace
+{
+  String format(const char *fmt, ...)
+  {
+    va_list args;
+    va_start(args,fmt);
+
+    char buf[256];
+
+#if defined(HAVE_SNPRINTF)
+
+    vsnprintf(buf, sizeof(buf), fmt, args);
+
+#elif defined(HAVE_SPRINTF_S)
+
+    vsprintf_s(buf, fmt, args);
+
 #else
-# define SPRINTF sprintf
+
+    // Be careful. May cause a buffer overflow.  
+    vsprintf(buf, fmt, args);
+
 #endif
 
-using namespace TagLib;
+    va_end(args);
+
+    return String(buf);
+  }
+}
 
 class MP4::Item::ItemPrivate 
 {
@@ -242,37 +267,31 @@ String
 MP4::Item::toString() const
 {
   StringList desc;
-  char tmp[256];
   switch (d->type) {
     case TypeBool:
       return d->m_bool ? "true" : "false";
     case TypeInt:
-      SPRINTF(tmp, "%d", d->m_int);
-      return tmp;
+      return format("%d", d->m_int);
     case TypeIntPair:
-      SPRINTF(tmp, "%d/%d", d->m_intPair.first, d->m_intPair.second);
-      return tmp;
+      return format("%d/%d", d->m_intPair.first, d->m_intPair.second);
     case TypeByte:
-      SPRINTF(tmp, "%d", d->m_byte);
-      return tmp;
+      return format("%d", d->m_byte);
     case TypeUInt:
-      SPRINTF(tmp, "%u", d->m_uint);
-      return tmp;
+      return format("%u", d->m_uint);
     case TypeLongLong:
-      SPRINTF(tmp, "%lld", d->m_longlong);
-      return tmp;
+      return format("%lld", d->m_longlong);
     case TypeStringList:
       return d->m_stringList.toString(" / ");
     case TypeByteVectorList:
       for(TagLib::uint i = 0; i < d->m_byteVectorList.size(); i++) {
-        SPRINTF(tmp, "[%d bytes of data]", static_cast<int>(d->m_byteVectorList[i].size()));
-        desc.append(tmp);
+        desc.append(format(
+          "[%d bytes of data]", static_cast<int>(d->m_byteVectorList[i].size())));
       }
       return desc.toString(", ");
     case TypeCoverArtList:
       for(TagLib::uint i = 0; i < d->m_coverArtList.size(); i++) {
-        SPRINTF(tmp, "[%d bytes of data]", static_cast<int>(d->m_coverArtList[i].data().size()));
-        desc.append(tmp);
+        desc.append(format(
+          "[%d bytes of data]", static_cast<int>(d->m_coverArtList[i].data().size())));
       }
       return desc.toString(", ");
     case TypeUndefined: