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, 5 insertions, 4 deletions

diff --git a/src/doom/st_stuff.c b/src/doom/st_stuff.c
index b9d9aefd..d00eeba1 100644
--- a/src/doom/st_stuff.c
+++ b/src/doom/st_stuff.c
@@ -33,6 +33,7 @@
 #include "i_system.h"
 #include "i_video.h"
 #include "z_zone.h"
+#include "m_misc.h"
 #include "m_random.h"
 #include "w_wad.h"
 
@@ -598,10 +599,10 @@ ST_Responder (event_t* ev)
       else if (cht_CheckCheat(&cheat_mypos, ev->data2))
       {
         static char buf[ST_MSGWIDTH];
-        snprintf(buf, sizeof(buf), "ang=0x%x;x,y=(0x%x,0x%x)",
-                 players[consoleplayer].mo->angle,
-                 players[consoleplayer].mo->x,
-                 players[consoleplayer].mo->y);
+        M_snprintf(buf, sizeof(buf), "ang=0x%x;x,y=(0x%x,0x%x)",
+                   players[consoleplayer].mo->angle,
+                   players[consoleplayer].mo->x,
+                   players[consoleplayer].mo->y);
         plyr->message = buf;
       }
     }