mirror of https://github.com/etcd-io/bbolt.git
45 lines
931 B
Go
45 lines
931 B
Go
package bolt
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const magic uint32 = 0xED0CDAED
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type meta struct {
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magic uint32
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version uint32
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pageSize uint32
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flags uint32
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buckets pgid
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freelist pgid
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pgid pgid
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txid txid
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}
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// validate checks the marker bytes and version of the meta page to ensure it matches this binary.
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func (m *meta) validate() error {
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if m.magic != magic {
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return ErrInvalid
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} else if m.version != version {
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return ErrVersionMismatch
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}
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return nil
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}
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// copy copies one meta object to another.
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func (m *meta) copy(dest *meta) {
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dest.magic = m.magic
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dest.version = m.version
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dest.pageSize = m.pageSize
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dest.buckets = m.buckets
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dest.freelist = m.freelist
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dest.pgid = m.pgid
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dest.txid = m.txid
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}
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// write writes the meta onto a page.
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func (m *meta) write(p *page) {
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// Page id is either going to be 0 or 1 which we can determine by the transaction ID.
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p.id = pgid(m.txid % 2)
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p.flags |= metaPageFlag
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m.copy(p.meta())
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}
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