Use random-access-storage

Author: abluchet

.gitignore

@@ -0,0 +1 @@
+node_modules

.travis.yml

@@ -0,0 +1,14 @@
+language: node_js
+addons:
+    chrome: stable
+	apt:
+		packages:
+            - xvfb
+os:
+    - linux
+before_install:
+    - npm install browser-run browserify -g
+	- export DISPLAY=':99.0'
+	- Xvfb :99 -screen 0 1024x768x24 > /dev/null 2>&1 &
+node_js:
+    - "8"

index.js

@@ -1,4 +1,4 @@
-var Abstract = require('abstract-random-access')
+var Abstract = require('random-access-storage')
 var inherits = require('inherits')
 var nextTick = require('next-tick')
 var once = require('once')
@@ -11,11 +11,11 @@ var DELIM = '\0'
 module.exports = function (dbname, xopts) {
   if (!xopts) xopts = {}
   var idb = xopts.idb || (typeof window !== 'undefined'
-    ? window.indexedDB || window.mozIndexedDB
-      || window.webkitIndexedDB || window.msIndexedDB
+    ? window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB
     : null)
   if (!idb) throw new Error('indexedDB not present and not given')
-  var db = null, dbqueue = []
+  var db = null
+  var dbqueue = []
   if (typeof idb.open === 'function') {
     var req = idb.open(dbname)
     req.addEventListener('upgradeneeded', function () {
@@ -63,73 +63,73 @@ Store.prototype._blocks = function (i, j) {
   return blocks(this.size, i, j)
 }
 
-Store.prototype._read = function (offset, length, cb) {
+Store.prototype._read = function (req) {
   var self = this
-  cb = once(cb)
   var buffers = []
   self._store('readonly', function (err, store) {
-    if ((self.length || 0) < offset+length) {
-      return cb(new Error('Could not satisfy length'))
+    if ((self.length || 0) < req.offset + req.size) {
+      return req.callback(new Error('Could not satisfy length'), null)
     }
-    if (err) return cb(err)
-    var offsets = self._blocks(offset, offset+length)
+    if (err) return req.callback(err)
+    var offsets = self._blocks(req.offset, req.offset + req.size)
     var pending = offsets.length + 1
     var firstBlock = offsets.length > 0 ? offsets[0].block : 0
-    var j = 0
     for (var i = 0; i < offsets.length; i++) (function (o) {
       var key = self.name + DELIM + o.block
       backify(store.get(key), function (err, ev) {
-        if (err) return cb(err)
-        buffers[o.block-firstBlock] = ev.target.result
-          ? bufferFrom(ev.target.result.subarray(o.start,o.end))
-          : bufferAlloc(o.end-o.start)
-        if (--pending === 0) cb(null, Buffer.concat(buffers))
+        if (err) return req.callback(err)
+        buffers[o.block - firstBlock] = ev.target.result
+          ? bufferFrom(ev.target.result.subarray(o.start, o.end))
+          : bufferAlloc(o.end - o.start)
+        if (--pending === 0) req.callback(null, Buffer.concat(buffers))
       })
     })(offsets[i])
-    if (--pending === 0) cb(null, Buffer.concat(buffers))
+    if (--pending === 0) req.callback(null, Buffer.concat(buffers))
   })
 }
 
-Store.prototype._write = function (offset, buf, cb) {
+Store.prototype._write = function (req) {
   var self = this
-  cb = once(cb)
   self._store('readwrite', function (err, store) {
-    if (err) return cb(err)
-    var offsets = self._blocks(offset, offset + buf.length)
+    if (err) return req.callback(err)
+    var offsets = self._blocks(req.offset, req.offset + req.data.length)
     var pending = 1
     var buffers = {}
-    for (var i = 0; i < offsets.length; i++) (function (o,i) {
-      if (o.end-o.start === self.size) return
+    for (var i = 0; i < offsets.length; i++) (function (o, i) {
+      if (o.end - o.start === self.size) return
       pending++
       var key = self.name + DELIM + o.block
       backify(store.get(key), function (err, ev) {
-        if (err) return cb(err)
+        if (err) return req.callback(err)
         buffers[i] = bufferFrom(ev.target.result || bufferAlloc(self.size))
         if (--pending === 0) write(store, offsets, buffers)
       })
-    })(offsets[i],i)
+    })(offsets[i], i)
     if (--pending === 0) write(store, offsets, buffers)
   })
+
   function write (store, offsets, buffers) {
+    var block
     for (var i = 0, j = 0; i < offsets.length; i++) {
       var o = offsets[i]
       var len = o.end - o.start
       if (len === self.size) {
-        block = buf.slice(j,j+len)
+        block = req.data.slice(j, j + len)
       } else {
         block = buffers[i]
-        buf.copy(block, o.start, j, j+len)
+        req.data.copy(block, o.start, j, j + len)
       }
-      store.put(block,self.name + DELIM + o.block)
+      store.put(block, self.name + DELIM + o.block)
       j += len
     }
-    var length = Math.max(self.length || 0, offset + buf.length)
-    store.put(length, self.name + DELIM + "length")
+
+    var length = Math.max(self.length || 0, req.offset + req.data.length)
+    store.put(length, self.name + DELIM + 'length')
     store.transaction.addEventListener('complete', function () {
       self.length = length
-      cb(null)
+      req.callback(null)
     })
-    store.transaction.addEventListener('error', cb)
+    store.transaction.addEventListener('error', req.callback)
   }
 }
 
@@ -144,13 +144,15 @@ Store.prototype._store = function (mode, cb) {
   })
 }
 
-Store.prototype._open = function(cb) {
+Store.prototype._open = function (req) {
   var self = this
-  this._getdb(function(db) {
+  this._getdb(function (db) {
     self._store('readonly', function (err, store) {
-      backify(store.get(self.name + DELIM + "length"), function(err, ev) {
+      if (err) return req.callback(err)
+      backify(store.get(self.name + DELIM + 'length'), function (err, ev) {
+        if (err) return req.callback(err)
         self.length = ev.target.result || 0
-        cb(null)
+        req.callback(null)
       })
     })
   })