split out cache locking into separate file

4 files changed, 131 insertions, 102 deletions

diff --git a/lib/cache.js b/lib/cache.js
index 32fb9f832..88aff8038 100644
--- a/lib/cache.js
+++ b/lib/cache.js
@@ -1,3 +1,6 @@
+'use strict';
+/* jshint node: true */
+
 // XXX lib/utils/tar.js and this file need to be rewritten.
 
 // URL-to-cache folder mapping:
@@ -54,8 +57,6 @@ exports = module.exports = cache
 cache.read = read
 cache.clean = clean
 cache.unpack = unpack
-cache.lock = lock
-cache.unlock = unlock
 
 var mkdir = require("mkdirp")
   , spawn = require("child_process").spawn
@@ -76,7 +77,6 @@ var mkdir = require("mkdirp")
   , fileCompletion = require("./utils/completion/file-completion.js")
   , url = require("url")
   , chownr = require("chownr")
-  , lockFile = require("lockfile")
   , crypto = require("crypto")
   , retry = require("retry")
   , zlib = require("zlib")
@@ -85,6 +85,10 @@ var mkdir = require("mkdirp")
   , isGitUrl = require("./utils/is-git-url.js")
   , pathIsInside = require("path-is-inside")
   , http = require("http")
+  , getCacheStat = require("./cache/get-stat.js")
+  , locker = require("./utils/locker.js")
+  , lock = locker.lock
+  , unlock = locker.unlock
 
 cache.usage = "npm cache add <tarball file>"
             + "\nnpm cache add <folder>"
@@ -346,7 +350,7 @@ function fetchAndShaCheck (u, tmp, shasum, cb) {
 
     // validate that the url we just downloaded matches the expected shasum.
     sha.check(tmp, shasum, function (er) {
-      if (er != null && er.message) {
+      if (er && er.message) {
         // add original filename for better debuggability
         er.message = er.message + '\n' + 'From:     ' + u
       }
@@ -502,7 +506,7 @@ function checkGitDir (p, u, co, origUrl, silent, cb) {
         return cb(err)
       }
       exec(git, args, {cwd: p, env: env}, function (er, stdout, stderr) {
-        stdoutTrimmed = (stdout + "\n" + stderr).trim()
+        var stdoutTrimmed = (stdout + "\n" + stderr).trim()
         if (er || u !== stdout.trim()) {
           log.warn( "`git config --get remote.origin.url` returned "
                   + "wrong result ("+u+")", stdoutTrimmed )
@@ -1041,59 +1045,6 @@ function addLocalTarball (p, name, version, shasum, cb_) {
   })
 }
 
-// to maintain the cache dir's permissions consistently.
-var cacheStat = null
-function getCacheStat (cb) {
-  if (cacheStat) return cb(null, cacheStat)
-  fs.stat(npm.cache, function (er, st) {
-    if (er) return makeCacheDir(cb)
-    if (!st.isDirectory()) {
-      log.error("getCacheStat", "invalid cache dir %j", npm.cache)
-      return cb(er)
-    }
-    return cb(null, cacheStat = st)
-  })
-}
-
-function makeCacheDir (cb) {
-  if (!process.getuid) return mkdir(npm.cache, cb)
-
-  var uid = +process.getuid()
-    , gid = +process.getgid()
-
-  if (uid === 0) {
-    if (process.env.SUDO_UID) uid = +process.env.SUDO_UID
-    if (process.env.SUDO_GID) gid = +process.env.SUDO_GID
-  }
-  if (uid !== 0 || !process.env.HOME) {
-    cacheStat = {uid: uid, gid: gid}
-    return mkdir(npm.cache, afterMkdir)
-  }
-
-  fs.stat(process.env.HOME, function (er, st) {
-    if (er) {
-      log.error("makeCacheDir", "homeless?")
-      return cb(er)
-    }
-    cacheStat = st
-    log.silly("makeCacheDir", "cache dir uid, gid", [st.uid, st.gid])
-    return mkdir(npm.cache, afterMkdir)
-  })
-
-  function afterMkdir (er, made) {
-    if (er || !cacheStat || isNaN(cacheStat.uid) || isNaN(cacheStat.gid)) {
-      return cb(er, cacheStat)
-    }
-
-    if (!made) return cb(er, cacheStat)
-
-    // ensure that the ownership is correct.
-    chownr(made, cacheStat.uid, cacheStat.gid, function (er) {
-      return cb(er, cacheStat)
-    })
-  }
-}
-
 
 
 
@@ -1307,10 +1258,11 @@ function addTmpTarball (tgz, name, version, shasum, cb) {
     tmp = true
     name = 'tmp_' + crypto.randomBytes(6).toString('hex')
   }
+  var pdir
   if (!tmp) {
-    var pdir = path.resolve(npm.cache, name, version, "package")
+    pdir = path.resolve(npm.cache, name, version, "package")
   } else {
-    var pdir = path.resolve(npm.cache, name + version + "package")
+    pdir = path.resolve(npm.cache, name + version + "package")
   }
 
   getCacheStat(function (er, cs) {
@@ -1396,45 +1348,6 @@ function deprCheck (data) {
   }
 }
 
-function lockFileName (u) {
-  var c = u.replace(/[^a-zA-Z0-9]+/g, "-").replace(/^-+|-+$/g, "")
-    , h = crypto.createHash("sha1").update(u).digest("hex")
-  h = h.substr(0, 8)
-  c = c.substr(-32)
-  log.silly("lockFile", h + "-" + c, u)
-  return path.resolve(npm.config.get("cache"), h + "-" + c + ".lock")
-}
-
-var myLocks = {}
-function lock (u, cb) {
-  // the cache dir needs to exist already for this.
-  getCacheStat(function (er, cs) {
-    if (er) return cb(er)
-    var opts = { stale: npm.config.get("cache-lock-stale")
-               , retries: npm.config.get("cache-lock-retries")
-               , wait: npm.config.get("cache-lock-wait") }
-    var lf = lockFileName(u)
-    log.verbose("lock", u, lf)
-    lockFile.lock(lf, opts, function(er) {
-      if (!er) myLocks[lf] = true
-      cb(er)
-    })
-  })
-}
-
-function unlock (u, cb) {
-  var lf = lockFileName(u)
-    , locked = myLocks[lf]
-  if (locked === false) {
-    return process.nextTick(cb)
-  } else if (locked === true) {
-    myLocks[lf] = false
-    lockFile.unlock(lockFileName(u), cb)
-  } else {
-    throw new Error("Attempt to unlock " + u + ", which hasn't been locked")
-  }
-}
-
 function needName(er, data) {
   return er ? er
        : (data && !data.name) ? new Error("No name provided")
diff --git a/lib/cache/get-stat.js b/lib/cache/get-stat.js
new file mode 100644
index 000000000..5e9709731
--- /dev/null
+++ b/lib/cache/get-stat.js
@@ -0,0 +1,62 @@
+'use strict';
+/* jshint node: true */
+
+var fs = require("fs")
+
+var npm = require("../npm.js")
+var log = require("npmlog")
+var mkdir = require("mkdirp")
+var chownr = require("chownr")
+
+function makeCacheDir (cb) {
+  if (!process.getuid) return mkdir(npm.cache, cb)
+
+  var uid = +process.getuid()
+    , gid = +process.getgid()
+
+  if (uid === 0) {
+    if (process.env.SUDO_UID) uid = +process.env.SUDO_UID
+    if (process.env.SUDO_GID) gid = +process.env.SUDO_GID
+  }
+  if (uid !== 0 || !process.env.HOME) {
+    cacheStat = {uid: uid, gid: gid}
+    return mkdir(npm.cache, afterMkdir)
+  }
+
+  fs.stat(process.env.HOME, function (er, st) {
+    if (er) {
+      log.error("makeCacheDir", "homeless?")
+      return cb(er)
+    }
+    cacheStat = st
+    log.silly("makeCacheDir", "cache dir uid, gid", [st.uid, st.gid])
+    return mkdir(npm.cache, afterMkdir)
+  })
+
+  function afterMkdir (er, made) {
+    if (er || !cacheStat || isNaN(cacheStat.uid) || isNaN(cacheStat.gid)) {
+      return cb(er, cacheStat)
+    }
+
+    if (!made) return cb(er, cacheStat)
+
+    // ensure that the ownership is correct.
+    chownr(made, cacheStat.uid, cacheStat.gid, function (er) {
+      return cb(er, cacheStat)
+    })
+  }
+}
+
+// to maintain the cache dir's permissions consistently.
+var cacheStat = null
+module.exports = function getCacheStat (cb) {
+  if (cacheStat) return cb(null, cacheStat)
+  fs.stat(npm.cache, function (er, st) {
+    if (er) return makeCacheDir(cb)
+    if (!st.isDirectory()) {
+      log.error("getCacheStat", "invalid cache dir %j", npm.cache)
+      return cb(er)
+    }
+    return cb(null, cacheStat = st)
+  })
+}
diff --git a/lib/utils/locker.js b/lib/utils/locker.js
new file mode 100644
index 000000000..e3c8f2e80
--- /dev/null
+++ b/lib/utils/locker.js
@@ -0,0 +1,54 @@
+'use strict';
+/* jshint node: true */
+var crypto = require("crypto")
+var path = require("path")
+
+var npm = require("../npm.js")
+var lockFile = require("lockfile")
+var log = require("npmlog")
+var getCacheStat = require("../cache/get-stat.js")
+
+function lockFileName (u) {
+  var c = u.replace(/[^a-zA-Z0-9]+/g, "-").replace(/^-+|-+$/g, "")
+    , h = crypto.createHash("sha1").update(u).digest("hex")
+  h = h.substr(0, 8)
+  c = c.substr(-32)
+  log.silly("lockFile", h + "-" + c, u)
+  return path.resolve(npm.config.get("cache"), h + "-" + c + ".lock")
+}
+
+var myLocks = {}
+function lock (u, cb) {
+  // the cache dir needs to exist already for this.
+  getCacheStat(function (er, cs) {
+    if (er) return cb(er)
+    var opts = { stale: npm.config.get("cache-lock-stale")
+               , retries: npm.config.get("cache-lock-retries")
+               , wait: npm.config.get("cache-lock-wait") }
+    var lf = lockFileName(u)
+    log.verbose("lock", u, lf)
+    lockFile.lock(lf, opts, function(er) {
+      if (!er) myLocks[lf] = true
+      cb(er)
+    })
+  })
+}
+
+function unlock (u, cb) {
+  var lf = lockFileName(u)
+    , locked = myLocks[lf]
+  if (locked === false) {
+    return process.nextTick(cb)
+  } else if (locked === true) {
+    myLocks[lf] = false
+    lockFile.unlock(lockFileName(u), cb)
+  } else {
+    throw new Error("Attempt to unlock " + u + ", which hasn't been locked")
+  }
+}
+
+module.exports = {
+  lock: lock,
+  unlock: unlock,
+  _lockFileName: lockFileName
+}
diff --git a/lib/utils/tar.js b/lib/utils/tar.js
index b73c134e4..3121bb028 100644
--- a/lib/utils/tar.js
+++ b/lib/utils/tar.js
@@ -8,7 +8,6 @@ var npm = require("../npm.js")
   , uidNumber = require("uid-number")
   , rm = require("./gently-rm.js")
   , readJson = require("read-package-json")
-  , cache = require("../cache.js")
   , myUid = process.getuid && process.getuid()
   , myGid = process.getgid && process.getgid()
   , tar = require("tar")
@@ -16,13 +15,14 @@ var npm = require("../npm.js")
   , fstream = require("fstream")
   , Packer = require("fstream-npm")
   , lifecycle = require("./lifecycle.js")
+  , locker = require("./locker.js")
 
 function lock(path, cb) {
-  return cache.lock('tar://' + path, cb)
+  return locker.lock('tar://' + path, cb)
 }
 
 function unlock(path, cb) {
-  return cache.unlock('tar://' + path, cb)
+  return locker.unlock('tar://' + path, cb)
 }
 
 if (process.env.SUDO_UID && myUid === 0) {