mirror of https://github.com/etcd-io/bbolt.git
44 lines
892 B
Go
44 lines
892 B
Go
package bolt
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const magic uint32 = 0xDEADC0DE
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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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pgid pgid
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free pgid
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sys pgid
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txnid txnid
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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 InvalidError
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} else if m.version != version {
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return VersionMismatchError
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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.pgid = m.pgid
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dest.free = m.free
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dest.txnid = m.txnid
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dest.sys = m.sys
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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 Txn ID.
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p.id = pgid(m.txnid % 2)
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p.flags |= p_meta
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m.copy(p.meta())
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}
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