GDB support for Android in devtools' debugger.

mojo/devtools/common/android_gdb/remote_file_connection.py

Index: mojo/devtools/common/android_gdb/remote_file_connection.py
diff --git a/mojo/devtools/common/android_gdb/remote_file_connection.py b/mojo/devtools/common/android_gdb/remote_file_connection.py
new file mode 100644
index 0000000000000000000000000000000000000000..9759cdb6ded75d5117a6981dccc0bbfedb1ceb45
--- /dev/null
+++ b/mojo/devtools/common/android_gdb/remote_file_connection.py
@@ -0,0 +1,69 @@
+# Copyright 2015 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.
+
+import socket
+import struct
+
+
+class RemoteFileConnectionException(Exception):
+  def __init__(self, *args, **kwargs):
+    Exception.__init__(self, *args, **kwargs)
+
+
+class RemoteFileConnection(object):
+  """Client for remote_file_reader server, allowing to read files on an
+  remote device.
+  """
+  def __init__(self, host, port):
+    self._host = host
+    self._port = port
+    self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    self._size_struct = struct.Struct("!i")
+
+  def __del__(self):
+    self.disconnect()
+
+  def connect(self):
+    self._socket.connect((self._host, self._port))
+
+  def disconnect(self):
+    self._socket.close()
+
+  def open(self, filename):
+    self._send("O %s\n" % filename)
+    result = self._receive(1)
+    if result != 'O':
+      raise RemoteFileConnectionException("Unable to open file " + filename)
+
+  def seek(self, pos, mode=0):
+    self._send("S %d %d\n" % (pos, mode))
+    result = self._receive(1)
+    if result != 'O':
+      raise RemoteFileConnectionException("Unable to seek in file.")
+
+  def read(self, size=0):
+    assert size > 0
+    self._send("R %d\n" % size)
+    result = self._receive(1)
+    if result != 'O':
+      raise RemoteFileConnectionException("Unable to read file.")
+    read_size = self._size_struct.unpack(self._receive(4))[0]
+    return self._receive(read_size)
+
+  def _send(self, data):
+    while len(data) > 0:
+      sent = self._socket.send(data)
+      if sent == 0:
+        raise RemoteFileConnectionException("Socket connection broken.")
+      data = data[sent:]
+
+  def _receive(self, length):
+    result = []
+    while length > 0:
+      chunk = self._socket.recv(length)
+      if chunk == '':
+        raise RemoteFileConnectionException("Socket connection broken.")
+      result.append(chunk)
+      length -= len(chunk)
+    return ''.join(result)