diff options
Diffstat (limited to 'subtle/overlap.go')
-rw-r--r-- | subtle/overlap.go | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/subtle/overlap.go b/subtle/overlap.go new file mode 100644 index 0000000..82ab250 --- /dev/null +++ b/subtle/overlap.go @@ -0,0 +1,18 @@ +//go:build !purego + +package subtle + +import "unsafe" + +func AnyOverlap(x, y []byte) bool { + return len(x) > 0 && len(y) > 0 && + uintptr(unsafe.Pointer(&x[0])) <= uintptr(unsafe.Pointer(&y[len(y)-1])) && + uintptr(unsafe.Pointer(&y[0])) <= uintptr(unsafe.Pointer(&x[len(x)-1])) +} + +func InexactOverlap(x, y []byte) bool { + if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] { + return false + } + return AnyOverlap(x, y) +} |