asar: Add support in fs.realpathSync

atom/common/api/atom_api_asar.cc

@@ -65,6 +65,15 @@ class Archive : public mate::Wrappable {
     return mate::ConvertToV8(isolate, files);
   }
 
+  // Returns the path of file with symbol link resolved.
+  v8::Handle<v8::Value> Realpath(v8::Isolate* isolate,
+                                 const base::FilePath& path) {
+    base::FilePath realpath;
+    if (!archive_ || !archive_->Realpath(path, &realpath))
+      return v8::False(isolate);
+    return mate::ConvertToV8(isolate, realpath);
+  }
+
   // Copy the file out into a temporary file and returns the new path.
   v8::Handle<v8::Value> CopyFileOut(v8::Isolate* isolate,
                                     const base::FilePath& path) {
@@ -86,6 +95,7 @@ class Archive : public mate::Wrappable {
         .SetMethod("getFileInfo", &Archive::GetFileInfo)
         .SetMethod("stat", &Archive::Stat)
         .SetMethod("readdir", &Archive::Readdir)
+        .SetMethod("realpath", &Archive::Realpath)
         .SetMethod("copyFileOut", &Archive::CopyFileOut)
         .SetMethod("destroy", &Archive::Destroy);
   }

atom/common/asar/archive.cc

@@ -206,6 +206,24 @@ bool Archive::Readdir(const base::FilePath& path,
   return true;
 }
 
+bool Archive::Realpath(const base::FilePath& path, base::FilePath* realpath) {
+  if (!header_)
+    return false;
+
+  const base::DictionaryValue* node;
+  if (!GetNodeFromPath(path.AsUTF8Unsafe(), header_.get(), &node))
+    return false;
+
+  std::string link;
+  if (node->GetString("link", &link)) {
+    *realpath = base::FilePath::FromUTF8Unsafe(link);
+    return true;
+  }
+
+  *realpath = path;
+  return true;
+}
+
 bool Archive::CopyFileOut(const base::FilePath& path, base::FilePath* out) {
   if (external_files_.contains(path)) {
     *out = external_files_.get(path)->path();

atom/common/asar/archive.h

@@ -51,6 +51,9 @@ class Archive {
   // Fs.readdir(path).
   bool Readdir(const base::FilePath& path, std::vector<base::FilePath>* files);
 
+  // Fs.realpath(path).
+  bool Realpath(const base::FilePath& path, base::FilePath* realpath);
+
   // Copy the file into a temporary file, and return the new path.
   bool CopyFileOut(const base::FilePath& path, base::FilePath* out);
 

atom/common/lib/asar.coffee

@@ -75,7 +75,7 @@ fs.lstat = (p, callback) ->
   return lstat p, callback unless isAsar
 
   archive = getOrCreateArchive asarPath
-  return callback throw new Error("Invalid package #{asarPath}") unless archive
+  return callback new Error("Invalid package #{asarPath}") unless archive
 
   stats = getOrCreateArchive(asarPath).stat filePath
   return callback createNotFoundError(asarPath, filePath) unless stats
@@ -109,13 +109,26 @@ fs.statSyncNoException = (p) ->
   return false unless stats
   asarStatsToFsStats stats
 
+realpathSync = fs.realpathSync
+fs.realpathSync = (p) ->
+  [isAsar, asarPath, filePath] = splitPath p
+  return realpathSync.apply this, arguments unless isAsar
+
+  archive = getOrCreateArchive asarPath
+  throw new Error("Invalid package #{asarPath}") unless archive
+
+  real = archive.realpath filePath
+  throw createNotFoundError(asarPath, filePath) unless real
+
+  path.join realpathSync(asarPath), real
+
 exists = fs.exists
 fs.exists = (p, callback) ->
   [isAsar, asarPath, filePath] = splitPath p
   return exists p, callback unless isAsar
 
   archive = getOrCreateArchive asarPath
-  return callback throw new Error("Invalid package #{asarPath}") unless archive
+  return callback new Error("Invalid package #{asarPath}") unless archive
 
   process.nextTick -> callback archive.stat(filePath) isnt false
 
@@ -140,7 +153,7 @@ fs.readFile = (p, options, callback) ->
     options = undefined
 
   archive = getOrCreateArchive asarPath
-  return callback throw new Error("Invalid package #{asarPath}") unless archive
+  return callback new Error("Invalid package #{asarPath}") unless archive
 
   info = archive.getFileInfo filePath
   return callback createNotFoundError(asarPath, filePath) unless info
@@ -200,7 +213,7 @@ fs.readdir = (p, callback) ->
   return readdir.apply this, arguments unless isAsar
 
   archive = getOrCreateArchive asarPath
-  return callback throw new Error("Invalid package #{asarPath}") unless archive
+  return callback new Error("Invalid package #{asarPath}") unless archive
 
   files = archive.readdir filePath
   return callback createNotFoundError(asarPath, filePath) unless files