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Diffstat (limited to 'vendor/github.com/boltdb/bolt/bolt_arm.go')
-rw-r--r--vendor/github.com/boltdb/bolt/bolt_arm.go28
1 files changed, 28 insertions, 0 deletions
diff --git a/vendor/github.com/boltdb/bolt/bolt_arm.go b/vendor/github.com/boltdb/bolt/bolt_arm.go
new file mode 100644
index 000000000..7e5cb4b94
--- /dev/null
+++ b/vendor/github.com/boltdb/bolt/bolt_arm.go
@@ -0,0 +1,28 @@
+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
+}