Mojo content handler shebang support

mojo/common/data_pipe_utils.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MOJO_SHELL_DATA_PIPE_UTILS_H_
 #define MOJO_SHELL_DATA_PIPE_UTILS_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
@@ skipping 17 matching lines @@
     base::TaskRunner* task_runner,
     const base::Callback<void(bool /*success*/)>& callback);
 
 // Copies the data from |source| into |contents| and returns true on success and
 // false on error.  In case of I/O error, |contents| holds the data that could
 // be read from source before the error occurred.
 bool MOJO_COMMON_EXPORT BlockingCopyToString(
     ScopedDataPipeConsumerHandle source,
     std::string* contents);
 
+// Return true and the first newline terminated line from source. Return false
+// if more than max_line_length bytes are scanned without seeing a newline, or
+// if the timeout is exceeded.
+bool MOJO_COMMON_EXPORT BlockingPeekLine(
+    DataPipeConsumerHandle source,
+    std::string* line,
+    size_t max_line_length,
+    MojoDeadline timeout);
+
+// Return true and the first bytes_length bytes from source. Return false
+// if the timeout is exceeded.
+bool MOJO_COMMON_EXPORT BlockingPeekNBytes(
+    DataPipeConsumerHandle source,
+    std::string* bytes,
+    size_t bytes_length,
+    MojoDeadline timeout);
+
 }  // namespace common
 }  // namespace mojo
 
 #endif  // MOJO_SHELL_DATA_PIPE_UTILS_H_