From 2c25c64db395d2f2f73f8d2f66ae9886ce07ef8b Mon Sep 17 00:00:00 2001
From: Douglas Clowes <dcl@ansto.gov.au>
Date: Tue, 18 Feb 2014 11:27:53 +1100
Subject: [PATCH] Enable GNU GCC type checking of format arguments for our
 functions

---
 conman.h   |  9 ++++++++-
 errormsg.h |  9 ++++++++-
 servlog.h  | 11 +++++++++--
 trace.h    | 19 +++++++++++++------
 4 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/conman.h b/conman.h
index 8f085332..40308a3b 100644
--- a/conman.h
+++ b/conman.h
@@ -91,7 +91,14 @@ void SCSignalFunction(void *pCon, int iSignal, void *pSigData);
 /* ***************************** I/O **************************************  */
 void SCSetOutputClass(SConnection * self, int iClass);
 int SCWrite(SConnection * self, char *pBuffer, int iOut);
-int SCPrintf(SConnection * self, int iOut, char *fmt, ...);
+#if __GNUC__ > 2
+#define G_GNUC_PRINTF( format_idx, arg_idx )    \
+  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
+#else
+#define G_GNUC_PRINTF( format_idx, arg_idx )
+#endif
+int SCPrintf(SConnection * self, int iOut, char *fmt, ...) G_GNUC_PRINTF (3, 4);
+#undef G_GNUC_PRINTF
 int SCRead(SConnection * self, char *pBuffer, int iBufLen);
 int SCPrompt(SConnection * pCon, char *pPrompt, char *pResult, int iLen);
 int SCSendOK(SConnection * self);
diff --git a/errormsg.h b/errormsg.h
index 5f792147..e7630edc 100644
--- a/errormsg.h
+++ b/errormsg.h
@@ -35,7 +35,14 @@ typedef struct {
  *  \return the new error message list head
  */
 
-void ErrPutMsg(ErrList *list, char *fmt, ...);
+#if __GNUC__ > 2
+#define G_GNUC_PRINTF( format_idx, arg_idx )    \
+  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
+#else
+#define G_GNUC_PRINTF( format_idx, arg_idx )
+#endif
+void ErrPutMsg(ErrList *list, char *fmt, ...) G_GNUC_PRINTF (2, 3);
+#undef G_GNUC_PRINTF
 
 /** \brief Get the most recent error message
  *  \param list the error list
diff --git a/servlog.h b/servlog.h
index 0b928cd7..ebe788d1 100644
--- a/servlog.h
+++ b/servlog.h
@@ -20,9 +20,16 @@ void SICSLogWriteTime(char *ptext, OutCode eOut, struct timeval *tp);
 void SICSLogWriteHex(const char *text, int count, OutCode eOut);
 void SICSLogWriteHexTime(const char *text, int count, OutCode eOut,
                          struct timeval *tp);
-void SICSLogPrintf(OutCode eOut, const char *fmt, ...);
+#if __GNUC__ > 2
+#define G_GNUC_PRINTF( format_idx, arg_idx )    \
+  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
+#else
+#define G_GNUC_PRINTF( format_idx, arg_idx )
+#endif
+void SICSLogPrintf(OutCode eOut, const char *fmt, ...) G_GNUC_PRINTF (2, 3);
 void SICSLogTimePrintf(OutCode eOut, struct timeval *tp, const char *fmt,
-                       ...);
+                       ...) G_GNUC_PRINTF (3, 4);
+#undef G_GNUC_PRINTF
 void SICSLogEnable(int flag);
 int KillCapture(SConnection * pCon);
 
diff --git a/trace.h b/trace.h
index afd6d71b..24a266d5 100644
--- a/trace.h
+++ b/trace.h
@@ -18,17 +18,24 @@
  * the socket number, a host:port or something appropriate
  * which tells us where the stuff is going to or coming from.
  */
-void traceIO(char *id, char *format, ...);
-void traceDevice(char *id, char *format, ...);
-void traceCommand(char *id, char *format, ...);
-void tracePar(char *id, char *format, ...);
-void traceSys(char *id, char *format, ...);
+#if __GNUC__ > 2
+#define G_GNUC_PRINTF( format_idx, arg_idx )    \
+  __attribute__((__format__ (__printf__, format_idx, arg_idx)))
+#else
+#define G_GNUC_PRINTF( format_idx, arg_idx )
+#endif
+void traceIO(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
+void traceDevice(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
+void traceCommand(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
+void tracePar(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
+void traceSys(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
 void traceprint(char *sub, char *id,char *data);
 
 /**
  * A debugging trace. This has to be switched on separately
  */
-void traceDebug(char *id, char *format, ...);
+void traceDebug(char *id, char *format, ...) G_GNUC_PRINTF (2, 3);
+#undef G_GNUC_PRINTF
 
 /*
  * 1 when tracing active, 0 else