From c5a22c4344f17169bb20e122e9d935c62aedc063 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 2 Sep 2013 11:04:39 +0300 Subject: range: add min/max operations on ranges Signed-off-by: Michael S. Tsirkin --- include/qemu/range.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/include/qemu/range.h b/include/qemu/range.h index 4a0780d..aae9720 100644 --- a/include/qemu/range.h +++ b/include/qemu/range.h @@ -17,6 +17,24 @@ struct Range { uint64_t end; /* 1 + the last byte. 0 if range empty or ends at ~0x0LL. */ }; +static inline void range_extend(Range *range, Range *extend_by) +{ + if (!extend_by->begin && !extend_by->end) { + return; + } + if (!range->begin && !range->end) { + *range = *extend_by; + return; + } + if (range->begin > extend_by->begin) { + range->begin = extend_by->begin; + } + /* Compare last byte in case region ends at ~0x0LL */ + if (range->end - 1 < extend_by->end - 1) { + range->end = extend_by->end; + } +} + /* Get last byte of a range from offset + length. * Undefined for ranges that wrap around 0. */ static inline uint64_t range_get_last(uint64_t offset, uint64_t len) -- cgit v1.1