git ssb

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var buffered = require('pull-buffered')
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var util = require('./util')
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function rev(str) {
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  return str === '0000000000000000000000000000000000000000' ? null : str
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}
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// from pull-stream/source.js
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function abortCb(cb, abort, onAbort) {
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  cb(abort)
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  onAbort && onAbort(abort === true ? null: abort)
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  return
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}
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function pktLineEncode(read) {
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  var ended
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  return function (end, cb) {
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    if (ended) return cb(ended)
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    read(end, function (end, data) {
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      if (ended = end) {
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        cb(end)
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      } else {
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        if (data)
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          data += '\n'
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        else
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          data = ''
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        var len = data ? data.length + 4 : 0
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        var hexLen = ('000' + len.toString(16)).substr(-4)
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        var pkt = hexLen + data
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        // console.error('>', JSON.stringify(pkt))
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        cb(end, pkt)
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      }
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    })
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  }
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}
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function pktLineDecode(read, options) {
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  var b = buffered(read)
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  var readPrefix = b.chunks(4)
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  var ended
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  function readPackLine(abort, cb) {
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    if (ended) return cb(ended)
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    readPrefix(abort, function (end, buf) {
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      if (ended = end) return cb(end)
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      var len = parseInt(buf, 16)
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      if (!len)
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        return cb(null, new Buffer(''))
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      b.chunks(len - 4)(null, function (end, buf) {
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        if (ended = end) return cb(end)
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        cb(end, buf)
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      })
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    })
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  }
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  function readPackLineStr(abort, cb) {
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    if (ended) return cb(ended)
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    readPackLine(abort, function (end, buf) {
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      if (ended = end) return cb(end)
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      // trim newline
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      var len = buf.length
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      if (buf[len - 1] == 0xa)
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        len--
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      var line = buf.toString('ascii', 0, len)
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      cb(null, line)
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    })
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  }
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  function readUpdate(abort, cb) {
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    readPackLine(abort, function (end, line) {
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      if (end) return cb(end)
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      if (!line.length) return cb(true)
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      var args = util.split3(line.toString('ascii'))
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      var args2 = util.split2(args[2], '\0')
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      var caps = args2[1]
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      if (caps) {
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        if (options.onCaps) {
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          var capsSet = {}
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          caps.split(' ').forEach(function (cap) {
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            capsSet[cap] = true
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          })
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          options.onCaps(capsSet)
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        }
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      }
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      cb(null, {
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        old: rev(args[0]),
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        new: rev(args[1]),
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        name: args2[0]
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      })
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    })
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  }
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  function havesWants(onEnd) {
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    return function readWant(abort, cb) {
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      readPackLineStr(abort, function (end, line) {
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        if (end) return abortCb(cb, end, onEnd)
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        if (line === 'done') return abortCb(cb, true, onEnd)
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        if (line.length === 0) return cb(null, {type: 'flush-pkt'})
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        var args = util.split3(line)
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        var caps = args[2]
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        if (caps) {
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          if (options.onCaps)
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            options.onCaps(caps)
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        }
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        cb(null, {
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          type: args[0],
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          hash: args[1],
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        })
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      })
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    }
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  }
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  b.pktLines = readPackLine
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  b.updates = readUpdate
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  b.wants = b.haves = havesWants
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  return b
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}
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exports.encode = pktLineEncode
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exports.decode = pktLineDecode
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