38 lines
871 B
Go
38 lines
871 B
Go
package acl
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import "fmt"
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// sets n-th bit in num (starting at 0).
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func setBit(num *uint32, n uint8) {
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*num |= 1 << n
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}
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// checks if n-th bit in num is set (starting at 0).
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func isBitSet(num uint32, n uint8) bool {
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mask := uint32(1 << n)
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return mask != 0 && num&mask == mask
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}
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// maps Op to op-section index in Basic. Filled on init.
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var mOrder map[Op]uint8
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// sets n-th bit in num for the given op. Panics if op is unsupported.
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func setOpBit(num *uint32, op Op, opBitPos uint8) {
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n, ok := mOrder[op]
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if !ok {
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panic(fmt.Sprintf("op is unsupported %v", op))
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}
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setBit(num, n*bitsPerOp+opBitPos)
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}
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// checks if n-th bit in num for the given op is set. Panics if op is unsupported.
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func isOpBitSet(num uint32, op Op, n uint8) bool {
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off, ok := mOrder[op]
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if !ok {
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panic(fmt.Sprintf("op is unsupported %v", op))
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}
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return isBitSet(num, bitsPerOp*off+n)
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}
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