Avoid compiler warnings on systems that have snprintf and/or vsnprintf

but do not bother to declare them in <stdio.h>.  Seems to be a more
common omission than you'd think...

src/configure.in

@@ -720,6 +720,16 @@ AC_CHECK_FUNC(vsnprintf,
 	      AC_DEFINE(HAVE_VSNPRINTF),
 	      SNPRINTF='snprintf.o')
 AC_SUBST(SNPRINTF)
+dnl Check whether <stdio.h> declares snprintf() and vsnprintf(); if not,
+dnl include/c.h will provide declarations.  Note this is a separate test
+dnl from whether the functions exist in the C library --- there are systems
+dnl that have the functions but don't bother to declare them :-(
+dnl Note: simple-minded pattern here will do wrong thing if stdio.h
+dnl declares vsnprintf() but not snprintf().  Hopefully there are no
+dnl systems that are *that* brain-damaged...
+AC_EGREP_HEADER(snprintf, stdio.h, AC_DEFINE(HAVE_SNPRINTF_DECL))
+AC_EGREP_HEADER(vsnprintf, stdio.h, AC_DEFINE(HAVE_VSNPRINTF_DECL))
+dnl
 dnl do this one the hard way in case isinf() is a macro
 AC_MSG_CHECKING(for isinf)
 AC_CACHE_VAL(ac_cv_func_or_macro_isinf,

src/include/c.h

@@ -7,7 +7,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: c.h,v 1.61 1999/07/17 20:18:25 momjian Exp $
+ * $Id: c.h,v 1.62 1999/12/20 00:51:21 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -789,11 +789,11 @@ extern char *vararg_format(const char *fmt,...);
  * in config.h we haven't yet included anything that defines size_t...
  */
 
-#ifndef HAVE_SNPRINTF
+#ifndef HAVE_SNPRINTF_DECL
 extern int	snprintf(char *str, size_t count, const char *fmt,...);
 #endif
 
-#ifndef HAVE_VSNPRINTF
+#ifndef HAVE_VSNPRINTF_DECL
 extern int	vsnprintf(char *str, size_t count, const char *fmt, va_list args);
 #endif
 

src/include/config.h.in

@@ -310,18 +310,24 @@
 # define gettimeofday(a,b) gettimeofday(a)
 #endif
 
-/* Set to 1 if you have snprintf() */
+/* Set to 1 if you have snprintf() in the C library */
 #undef HAVE_SNPRINTF
 
-/* Set to 1 if you have strerror() */
-#undef HAVE_STRERROR
+/* Set to 1 if your standard system headers declare snprintf() */
+#undef HAVE_SNPRINTF_DECL
 
-/* Set to 1 if you have vsnprintf() */
+/* Set to 1 if you have vsnprintf() in the C library */
 #undef HAVE_VSNPRINTF
 
+/* Set to 1 if your standard system headers declare vsnprintf() */
+#undef HAVE_VSNPRINTF_DECL
+
+/* Set to 1 if you have strerror() */
+#undef HAVE_STRERROR
+
 /*
  *	Set to 1 if you have isinf().
- *	These are all realated to port/isinf.c 
+ *	These are all related to port/isinf.c 
  */
 #undef HAVE_FPCLASS
 #undef HAVE_FP_CLASS

src/include/port/hpux.h

@@ -6,14 +6,6 @@ typedef struct
 	int			sema[4];
 } slock_t;
 
-/* HPUX 9 has snprintf in the library, so configure will set HAVE_SNPRINTF;
- * but it doesn't provide a prototype for it.  To suppress warning messages
- * from gcc, do this to make c.h provide the prototype:
- */
-#ifndef HAVE_VSNPRINTF
-#undef HAVE_SNPRINTF
-#endif
-
 #ifndef			BIG_ENDIAN
 #define			BIG_ENDIAN		4321
 #endif