Replace all snprintf() calls with M_snprintf().

The Windows API has an _snprintf function that is not the same as
Unix's snprintf(): if the string is truncated then no trailing NUL
character is appended. This makes the function unsafe. Define a
replacement/wrapper called M_snprintf that works the same but always
appends a trailing NUL, for safety on Windows and other OSes that
behave like this.

Do the same thing for vsnprintf(), and update HACKING to list
snprintf/vsnprintf as forbidden functions. This fixes #375;
thanks to Quasar for pointing out the different behavior of these
functions.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/doom/s_sound.c b/src/doom/s_sound.c
index 4e81b016..dc0473a3 100644
--- a/src/doom/s_sound.c
+++ b/src/doom/s_sound.c
@@ -38,6 +38,7 @@
 #include "sounds.h"
 #include "s_sound.h"
 
+#include "m_misc.h"
 #include "m_random.h"
 #include "m_argv.h"
 
@@ -638,7 +639,7 @@ void S_ChangeMusic(int musicnum, int looping)
     // get lumpnum if neccessary
     if (!music->lumpnum)
     {
-        snprintf(namebuf, sizeof(namebuf), "d_%s", DEH_String(music->name));
+        M_snprintf(namebuf, sizeof(namebuf), "d_%s", DEH_String(music->name));
         music->lumpnum = W_GetNumForName(namebuf);
     }