Support custom serial bitrates on OS X

chrome/browser/extensions/api/serial/serial_connection_posix.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/extensions/api/serial/serial_connection.h"
 
 #include <sys/ioctl.h>
 #include <termios.h>
 
 #if defined(OS_LINUX)
 #include <linux/serial.h>
 #endif
 
+#if defined(OS_MACOSX)
+#include <IOKit/serial/ioss.h>
+#endif
+
 namespace extensions {
 
 namespace {
 
 // Convert an integral bit rate to a nominal one. Returns |true|
 // if the conversion was successful and |false| otherwise.
 bool BitrateToSpeedConstant(int bitrate, speed_t* speed) {
 #define BITRATE_TO_SPEED_CASE(x) case x: *speed = B ## x; return true;
   switch (bitrate) {
     BITRATE_TO_SPEED_CASE(0)
@@ skipping 70 matching lines @@
     return false;
   }
   serial.flags = (serial.flags & ~ASYNC_SPD_MASK) | ASYNC_SPD_CUST;
   serial.custom_divisor = serial.baud_base / bitrate;
   if (serial.custom_divisor < 1) {
     serial.custom_divisor = 1;
   }
   cfsetispeed(config, B38400);
   cfsetospeed(config, B38400);
   return ioctl(file, TIOCSSERIAL, &serial) >= 0;
+#elif defined(OS_MACOSX)
+  speed_t speed = static_cast<speed_t>(bitrate);
+  return ioctl(file, IOSSIOSPEED, &speed) != -1;
 #else
   return false;
 #endif
 }
 
 }  // namespace
 
 bool SerialConnection::ConfigurePort(
     const api::serial::ConnectionOptions& options) {
   struct termios config;
@@ skipping 153 matching lines @@
   info->cts_flow_control.reset(new bool((config.c_cflag & CRTSCTS) != 0));
   return true;
 }
 
 std::string SerialConnection::MaybeFixUpPortName(
     const std::string &port_name) {
   return port_name;
 }
 
 }  // namespace extensions