(CHAR_BIT, TYPE_SIGNED, TYPE_MINIMUM, TYPE_MAXIMUM, INT_MAX): Define.

1 files changed, 16 insertions, 0 deletions

diff --git a/lib/safe-read.c b/lib/safe-read.c
index e4cb1d3a2..c189eb1a6 100644
--- a/lib/safe-read.c
+++ b/lib/safe-read.c
@@ -35,6 +35,22 @@ extern int errno;
 
 #include <limits.h>
 
+#ifndef CHAR_BIT
+# define CHAR_BIT 8
+#endif
+
+/* The extra casts work around common compiler bugs.  */
+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+/* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
+   It is necessary at least when t == time_t.  */
+#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
+			      ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
+#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
+
+#ifndef INT_MAX
+# define INT_MAX TYPE_MAXIMUM (int)
+#endif
+
 /* We don't pass an nbytes count > SSIZE_MAX to read() - POSIX says the
    effect would be implementation-defined.  Also we don't pass an nbytes
    count > INT_MAX but <= SSIZE_MAX to read() - this triggers a bug in