1 files changed, 83 insertions, 0 deletions
diff --git a/m4/stdbool.m4 b/m4/stdbool.m4
new file mode 100644
index 0000000..3f6b4bf
--- /dev/null
+++ b/m4/stdbool.m4
@@ -0,0 +1,83 @@
+# Check for stdbool.h that conforms to C99.
+
+dnl Copyright (C) 2002-2004 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# Prepare for substituting <stdbool.h> if it is not supported.
+
+AC_DEFUN([AM_STDBOOL_H],
+[
+  AC_REQUIRE([AC_HEADER_STDBOOL])
+
+  # Define two additional variables used in the Makefile substitution.
+
+  if test "$ac_cv_header_stdbool_h" = yes; then
+    STDBOOL_H=''
+  else
+    STDBOOL_H='stdbool.h'
+  fi
+  AC_SUBST([STDBOOL_H])
+
+  if test "$ac_cv_type__Bool" = yes; then
+    HAVE__BOOL=1
+  else
+    HAVE__BOOL=0
+  fi
+  AC_SUBST([HAVE__BOOL])
+])
+
+# This macro is only needed in autoconf <= 2.59.  Newer versions of autoconf
+# have this macro built-in.
+
+AC_DEFUN([AC_HEADER_STDBOOL],
+  [AC_CACHE_CHECK([for stdbool.h that conforms to C99],
+     [ac_cv_header_stdbool_h],
+     [AC_TRY_COMPILE(
+	[
+	  #include <stdbool.h>
+	  #ifndef bool
+	   "error: bool is not defined"
+	  #endif
+	  #ifndef false
+	   "error: false is not defined"
+	  #endif
+	  #if false
+	   "error: false is not 0"
+	  #endif
+	  #ifndef true
+	   "error: true is not defined"
+	  #endif
+	  #if true != 1
+	   "error: true is not 1"
+	  #endif
+	  #ifndef __bool_true_false_are_defined
+	   "error: __bool_true_false_are_defined is not defined"
+	  #endif
+
+	  struct s { _Bool s: 1; _Bool t; } s;
+
+	  char a[true == 1 ? 1 : -1];
+	  char b[false == 0 ? 1 : -1];
+	  char c[__bool_true_false_are_defined == 1 ? 1 : -1];
+	  char d[(bool) -0.5 == true ? 1 : -1];
+	  bool e = &s;
+	  char f[(_Bool) -0.0 == false ? 1 : -1];
+	  char g[true];
+	  char h[sizeof (_Bool)];
+	  char i[sizeof s.t];
+	  enum { j = false, k = true, l = false * true, m = true * 256 };
+	  _Bool n[m];
+	  char o[sizeof n == m * sizeof n[0] ? 1 : -1];
+	],
+	[
+	  return (!a + !b + !c + !d + !e + !f + !g + !h + !i + !j + !k + !l
+		  + !m + !n + !o);
+	],
+	[ac_cv_header_stdbool_h=yes],
+	[ac_cv_header_stdbool_h=no])])
+   AC_CHECK_TYPES([_Bool])
+   if test $ac_cv_header_stdbool_h = yes; then
+     AC_DEFINE(HAVE_STDBOOL_H, 1, [Define to 1 if stdbool.h conforms to C99.])
+   fi])