cmap: Explain corner case in CMAP_FOR_EACH comment.

[cascardo/ovs.git] / lib / type-props.h

diff --git a/lib/type-props.h b/lib/type-props.h
index c718cf1..e5f4fdc 100644 (file)
--- a/lib/type-props.h
+++ b/lib/type-props.h
@@ -1,17 +1,17 @@
 /*
- * Copyright (c) 2008 Nicira Networks.
+ * Copyright (c) 2008, 2011, 2015 Nicira, Inc.
  *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
  *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #ifndef TYPE_PROPS_H
@@ -19,14 +19,37 @@
 
 #include <limits.h>
 
+/* True if TYPE is _Bool, false otherwise. */
+#define TYPE_IS_BOOL(TYPE) ((TYPE) 1 == (TYPE) 2)
+
+/* True if TYPE is an integer type (including _Bool), false if it is a
+ * floating-point type. */
 #define TYPE_IS_INTEGER(TYPE) ((TYPE) 1.5 == (TYPE) 1)
-#define TYPE_IS_SIGNED(TYPE) ((TYPE) 0 > (TYPE) -1)
-#define TYPE_VALUE_BITS(TYPE) (sizeof(TYPE) * CHAR_BIT - TYPE_IS_SIGNED(TYPE))
-#define TYPE_MINIMUM(TYPE) (TYPE_IS_SIGNED(TYPE) \
-                            ? ~(TYPE)0 << TYPE_VALUE_BITS(TYPE) \
-                            : 0)
-#define TYPE_MAXIMUM(TYPE) (TYPE_IS_SIGNED(TYPE) \
-                            ? ~(~(TYPE)0 << TYPE_VALUE_BITS(TYPE)) \
-                            : (TYPE)-1)
+
+/* True if TYPE is a signed integer or floating point type, otherwise false. */
+#define TYPE_IS_SIGNED(TYPE) ((TYPE) 1 > (TYPE) -1)
+
+/* The number of value bits in an signed or unsigned integer TYPE:
+ *
+ *    - _Bool has 1 value bit.
+ *
+ *    - An N-bit unsigned integer type has N value bits.
+ *
+ *    - An N-bit signed integer type has N-1 value bits.
+ */
+#define TYPE_VALUE_BITS(TYPE) \
+    (TYPE_IS_BOOL(TYPE) ? 1 : sizeof(TYPE) * CHAR_BIT - TYPE_IS_SIGNED(TYPE))
+
+/* The minimum or maximum value of a signed or unsigned integer TYPE. */
+#define TYPE_MINIMUM(TYPE) (TYPE_IS_SIGNED(TYPE) ? -TYPE_MAXIMUM(TYPE) - 1 : 0)
+#define TYPE_MAXIMUM(TYPE) \
+    ((((TYPE)1 << (TYPE_VALUE_BITS(TYPE) - 1)) - 1) * 2 + 1)
+
+/* Number of decimal digits required to format an integer of the given TYPE.
+ * Includes space for a sign, if TYPE is signed, but not for a null
+ * terminator.
+ *
+ * The value is an overestimate. */
+#define INT_STRLEN(TYPE) (TYPE_IS_SIGNED(TYPE) + TYPE_VALUE_BITS(TYPE) / 3 + 1)
 
 #endif /* type-props.h */