configure: smarter way to handle fseeko() searching

Better handling of the replacement for fseeko() in its absence; also
look for the Windows _fseeki64() function.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

compiler.h

@@ -99,6 +99,20 @@ int vsnprintf(char *, size_t, const char *, va_list);
 # endif
 #endif
 
+/* Missing fseeko/ftello */
+#ifndef HAVE_FSEEKO
+# undef off_t                   /* Just in case it is a macro */
+# ifdef HAVE__FSEEKI64
+#  define fseeko _fseeki64
+#  define ftello _ftelli64
+#  define off_t  int64_t
+# else
+#  define fseeko fseek
+#  define ftello ftell
+#  define off_t  long
+# endif
+#endif
+
 #if !defined(HAVE_STRLCPY) || !HAVE_DECL_STRLCPY
 size_t strlcpy(char *, const char *, size_t);
 #endif

configure.in

@@ -139,8 +139,8 @@ AC_CHECK_FUNCS(canonicalize_file_name)
 AC_CHECK_FUNCS(_fullpath)
 AC_CHECK_FUNCS(pathconf)
 
-AC_TYPE_OFF_T
 AC_FUNC_FSEEKO
+AC_CHECK_FUNCS([_fseeki64])
 AC_CHECK_FUNCS([ftruncate _chsize _chsize_s])
 AC_CHECK_FUNCS([fileno])
 

nasmlib.c

@@ -459,11 +459,6 @@ void fwriteaddr(uint64_t data, int size, FILE * fp)
 
 #endif
 
-#ifndef HAVE_FSEEKO
-# define fseeko fseek
-# define ftello ftell
-#endif
-
 #ifdef HAVE_FILENO		/* Useless without fileno() */
 # ifdef HAVE__CHSIZE_S
 #  define nasm_ftruncate(fd,size) _chsize_s(fd,size)