61646d77af
Signed-off-by: Alexander Morozov <lk4d4@docker.com> Upstream-commit: f2614f2107c838d014d31b806e3b8a9f1395cb2b Component: engine
29 lines
831 B
Go
29 lines
831 B
Go
package bolt
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import "unsafe"
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// maxMapSize represents the largest mmap size supported by Bolt.
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const maxMapSize = 0x7FFFFFFF // 2GB
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// maxAllocSize is the size used when creating array pointers.
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const maxAllocSize = 0xFFFFFFF
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// Are unaligned load/stores broken on this arch?
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var brokenUnaligned bool
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func init() {
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// Simple check to see whether this arch handles unaligned load/stores
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// correctly.
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// ARM9 and older devices require load/stores to be from/to aligned
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// addresses. If not, the lower 2 bits are cleared and that address is
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// read in a jumbled up order.
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// See http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15414.html
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raw := [6]byte{0xfe, 0xef, 0x11, 0x22, 0x22, 0x11}
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val := *(*uint32)(unsafe.Pointer(uintptr(unsafe.Pointer(&raw)) + 2))
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brokenUnaligned = val != 0x11222211
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}
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