Fix npm#1555 Queue tar operations for windows

*Really* need to get a js tar implementation in there asap.

lib/utils/tar.js

@@ -24,22 +24,41 @@ exports.pack = pack
 exports.unpack = unpack
 exports.makeList = makeList
 
+var packQueue = []
+  , packing = false
 
-function pack (targetTarball, folder, pkg, dfc, cb) {
-  if (typeof cb !== "function") cb = dfc, dfc = true
+function pack (targetTarball, folder, pkg, dfc, cb_) {
+  if (typeof cb_ !== "function") cb_ = dfc, dfc = true
   folder = path.resolve(process.cwd(), folder)
   if (typeof pkg === "function") {
-    cb = pkg, pkg = null
+    cb_ = pkg, pkg = null
     return readJson(path.resolve(folder, "package.json"), function (er, pkg) {
-      if (er) return log.er(cb, "Couldn't find package.json in "+folder)(er)
-      pack(targetTarball, folder, pkg, dfc, cb)
+      if (er) return log.er(cb_, "Couldn't find package.json in "+folder)(er)
+      pack(targetTarball, folder, pkg, dfc, cb_)
     })
   }
   log.verbose(folder+" "+targetTarball, "pack")
   var parent = path.dirname(folder)
     , addFolder = path.basename(folder)
 
-  cb = log.er(cb, "Failed creating the tarball.")
+  cb_ = log.er(cb_, "Failed creating the tarball.")
+
+
+  // XXX Rip out all this crap and use a tar get gets along with windows.
+  if (packing && process.platform === "win32") {
+    packQueue.push([targetTarball, folder, pkg, dfc, cb_])
+    return
+  }
+
+  packing = true
+  function cb (er, data) {
+    packing = false
+    var next = packQueue.shift()
+    if (next) process.nextTick(function () {
+      pack.apply(null, next)
+    })
+    cb_(er, data)
+  }
 
   var confEx = npm.config.get("ignore")
   makeList(folder, pkg, dfc, function (er, files, cleanup) {
@@ -113,7 +132,26 @@ function unpack (tarball, unpackTarget, dMode, fMode, uid, gid, cb) {
   })
 }
 
-function unpack_ ( tarball, unpackTarget, dMode, fMode, uid, gid, cb ) {
+// XXX Rip all this crap out and use a tar that gets along with windows.
+var unpackQueue = []
+  , unpacking = false
+
+function unpack_ ( tarball, unpackTarget, dMode, fMode, uid, gid, cb_ ) {
+  if (unpacking && process.platform === "win32") {
+    unpackQueue.push([tarball, unpackTarget, dMode, fMode, uid, gid, cb_])
+    return
+  }
+
+  unpacking = true
+  function cb (er, data) {
+    unpacking = false
+    var next = unpackQueue.shift()
+    if (next) process.nextTick(function () {
+      unpack_.apply(null, next)
+    })
+    cb_(er, data)
+  }
+
   // If the desired target is /path/to/foo,
   // then unpack into /path/to/.foo.npm/{something}
   // rename that to /path/to/foo, and delete /path/to/.foo.npm