28 lines
831 B
Go
28 lines
831 B
Go
package bolt
|
|
|
|
import "unsafe"
|
|
|
|
// maxMapSize represents the largest mmap size supported by Bolt.
|
|
const maxMapSize = 0x7FFFFFFF // 2GB
|
|
|
|
// maxAllocSize is the size used when creating array pointers.
|
|
const maxAllocSize = 0xFFFFFFF
|
|
|
|
// Are unaligned load/stores broken on this arch?
|
|
var brokenUnaligned bool
|
|
|
|
func init() {
|
|
// Simple check to see whether this arch handles unaligned load/stores
|
|
// correctly.
|
|
|
|
// ARM9 and older devices require load/stores to be from/to aligned
|
|
// addresses. If not, the lower 2 bits are cleared and that address is
|
|
// read in a jumbled up order.
|
|
|
|
// See http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15414.html
|
|
|
|
raw := [6]byte{0xfe, 0xef, 0x11, 0x22, 0x22, 0x11}
|
|
val := *(*uint32)(unsafe.Pointer(uintptr(unsafe.Pointer(&raw)) + 2))
|
|
|
|
brokenUnaligned = val != 0x11222211
|
|
}
|