From 785ee4988b783600790c4b8763ae4c1fdd0170ec Mon Sep 17 00:00:00 2001
From: Sakthipriyan Vairamani <thefourtheye@users.noreply.github.com>
Date: Sat, 23 Jul 2016 10:12:43 +0530
Subject: [PATCH 1/2] fix chmod function arguments

`*chmod*` functions accept only `path` and `mode`. As we were using
`chownFix`, it misinterprets callback function passed to `chmod` as `gid`.
---
 polyfills.js | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/polyfills.js b/polyfills.js
index 5e4f480..ffba98e 100644
--- a/polyfills.js
+++ b/polyfills.js
@@ -44,17 +44,17 @@ function patch (fs) {
   fs.fchown = chownFix(fs.fchown)
   fs.lchown = chownFix(fs.lchown)
 
-  fs.chmod = chownFix(fs.chmod)
-  fs.fchmod = chownFix(fs.fchmod)
-  fs.lchmod = chownFix(fs.lchmod)
+  fs.chmod = chmodFix(fs.chmod)
+  fs.fchmod = chmodFix(fs.fchmod)
+  fs.lchmod = chmodFix(fs.lchmod)
 
   fs.chownSync = chownFixSync(fs.chownSync)
   fs.fchownSync = chownFixSync(fs.fchownSync)
   fs.lchownSync = chownFixSync(fs.lchownSync)
 
-  fs.chmodSync = chownFix(fs.chmodSync)
-  fs.fchmodSync = chownFix(fs.fchmodSync)
-  fs.lchmodSync = chownFix(fs.lchmodSync)
+  fs.chmodSync = chmodFixSync(fs.chmodSync)
+  fs.fchmodSync = chmodFixSync(fs.fchmodSync)
+  fs.lchmodSync = chmodFixSync(fs.lchmodSync)
 
   // if lchmod/lchown do not exist, then make them no-ops
   if (!fs.lchmod) {
@@ -202,6 +202,28 @@ function patchLutimes (fs) {
   }
 }
 
+function chmodFix (orig) {
+  if (!orig) return orig
+  return function (target, mode, cb) {
+    return orig.call(fs, target, mode, function (er, res) {
+      if (chownErOk(er)) er = null
+      cb(er, res)
+    })
+  }
+}
+
+function chmodFixSync (orig) {
+  if (!orig) return orig
+  return function (target, mode) {
+    try {
+      return orig.call(fs, target, mode)
+    } catch (er) {
+      if (!chownErOk(er)) throw er
+    }
+  }
+}
+
+
 function chownFix (orig) {
   if (!orig) return orig
   return function (target, uid, gid, cb) {

From 73a73fc9395912e6dd0922dd602727a7309c5a6e Mon Sep 17 00:00:00 2001
From: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Date: Tue, 26 Jul 2016 11:07:38 +0530
Subject: [PATCH 2/2] use callback only if it is available

---
 polyfills.js | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/polyfills.js b/polyfills.js
index ffba98e..1cc74c8 100644
--- a/polyfills.js
+++ b/polyfills.js
@@ -59,13 +59,13 @@ function patch (fs) {
   // if lchmod/lchown do not exist, then make them no-ops
   if (!fs.lchmod) {
     fs.lchmod = function (path, mode, cb) {
-      process.nextTick(cb)
+      if (cb) process.nextTick(cb)
     }
     fs.lchmodSync = function () {}
   }
   if (!fs.lchown) {
     fs.lchown = function (path, uid, gid, cb) {
-      process.nextTick(cb)
+      if (cb) process.nextTick(cb)
     }
     fs.lchownSync = function () {}
   }
@@ -121,20 +121,19 @@ function patch (fs) {
 
 function patchLchmod (fs) {
   fs.lchmod = function (path, mode, callback) {
-    callback = callback || noop
     fs.open( path
            , constants.O_WRONLY | constants.O_SYMLINK
            , mode
            , function (err, fd) {
       if (err) {
-        callback(err)
+        if (callback) callback(err)
         return
       }
       // prefer to return the chmod error, if one occurs,
       // but still try to close, and report closing errors if they occur.
       fs.fchmod(fd, mode, function (err) {
         fs.close(fd, function(err2) {
-          callback(err || err2)
+          if (callback) callback(err || err2)
         })
       })
     })
@@ -167,11 +166,13 @@ function patchLutimes (fs) {
   if (constants.hasOwnProperty("O_SYMLINK")) {
     fs.lutimes = function (path, at, mt, cb) {
       fs.open(path, constants.O_SYMLINK, function (er, fd) {
-        cb = cb || noop
-        if (er) return cb(er)
+        if (er) {
+          if (cb) cb(er)
+          return
+        }
         fs.futimes(fd, at, mt, function (er) {
           fs.close(fd, function (er2) {
-            return cb(er || er2)
+            if (cb) cb(er || er2)
           })
         })
       })
@@ -197,7 +198,7 @@ function patchLutimes (fs) {
     }
 
   } else {
-    fs.lutimes = function (_a, _b, _c, cb) { process.nextTick(cb) }
+    fs.lutimes = function (_a, _b, _c, cb) { if (cb) process.nextTick(cb) }
     fs.lutimesSync = function () {}
   }
 }
@@ -207,7 +208,7 @@ function chmodFix (orig) {
   return function (target, mode, cb) {
     return orig.call(fs, target, mode, function (er, res) {
       if (chownErOk(er)) er = null
-      cb(er, res)
+      if (cb) cb(er, res)
     })
   }
 }
@@ -229,7 +230,7 @@ function chownFix (orig) {
   return function (target, uid, gid, cb) {
     return orig.call(fs, target, uid, gid, function (er, res) {
       if (chownErOk(er)) er = null
-      cb(er, res)
+      if (cb) cb(er, res)
     })
   }
 }