From bf1b00712375bea65f2254dea8281fa646eebbd5 Mon Sep 17 00:00:00 2001 From: Blue Swirl Date: Sat, 18 Sep 2010 05:53:14 +0000 Subject: Introduce range.h Extract range functions from pci.h. These will be used by later patches by non-PCI devices. Adjust current users. Signed-off-by: Blue Swirl --- range.h | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 range.h (limited to 'range.h') diff --git a/range.h b/range.h new file mode 100644 index 0000000..3502372 --- /dev/null +++ b/range.h @@ -0,0 +1,29 @@ +#ifndef QEMU_RANGE_H +#define QEMU_RANGE_H + +/* 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) +{ + return offset + len - 1; +} + +/* Check whether a given range covers a given byte. */ +static inline int range_covers_byte(uint64_t offset, uint64_t len, + uint64_t byte) +{ + return offset <= byte && byte <= range_get_last(offset, len); +} + +/* Check whether 2 given ranges overlap. + * Undefined if ranges that wrap around 0. */ +static inline int ranges_overlap(uint64_t first1, uint64_t len1, + uint64_t first2, uint64_t len2) +{ + uint64_t last1 = range_get_last(first1, len1); + uint64_t last2 = range_get_last(first2, len2); + + return !(last2 < first1 || last1 < first2); +} + +#endif -- cgit v1.1