On Mon, May 13, 2013 at 09:20:08PM +0100, Peter Maydell wrote:
On 13 May 2013 21:01, Michael S. Tsirkin mst@redhat.com wrote:
Sometimes we need to pass ranges around, add a handy structure for this purpose.
Signed-off-by: Michael S. Tsirkin mst@redhat.com
include/qemu/range.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/include/qemu/range.h b/include/qemu/range.h index 3502372..4bcd346 100644 --- a/include/qemu/range.h +++ b/include/qemu/range.h @@ -1,6 +1,28 @@ #ifndef QEMU_RANGE_H #define QEMU_RANGE_H
+#include <inttypes.h>
+/*
- Operations on 64 address ranges.
missing "bit" ?
- Notes:
- ranges must not wrap around 0, but can include the last byte ~0x0LL.
- this can not represent a full 0 to ~0x0LL range.
- */
+/* A structure representing a range of addresses. */ +struct Range {
- uint64_t begin; /* First byte of the range, or 0 if empty. */
- uint64_t end; /* 1 + the last byte. 0 if range empty or ends at ~0x0LL. */
+}; +typedef struct Range Range;
+/* verify that range is not empty and does not overlap */
Doesn't overlap what?
I meant wrap around there.
Why isn't an empty range valid? The struct definition above says it's OK.
Yes it's a bad name. Should be range_non_empty or something.
+{
- return range->begin + 1 <= range->end;
+}
I note that memory.c defines its own concept of an AddrRange.
thanks -- PMM
Good point, maybe I'll reuse that or just use two 64 bit fields explicitly.