Adds USB writing for OS X.

chrome/utility/image_writer/disk_unmounter_mac.cc

Index: chrome/utility/image_writer/disk_unmounter_mac.cc
diff --git a/chrome/utility/image_writer/disk_unmounter_mac.cc b/chrome/utility/image_writer/disk_unmounter_mac.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bca3805c853dcab8d84306dfd3ac223a28697ef0
--- /dev/null
+++ b/chrome/utility/image_writer/disk_unmounter_mac.cc
@@ -0,0 +1,125 @@
+// 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.
+
+#include "chrome/utility/image_writer/disk_unmounter_mac.h"
+
+#include <sys/socket.h>
+#include <IOKit/storage/IOStorageProtocolCharacteristics.h>
+
+#include "base/message_loop/message_loop_proxy.h"
+#include "base/message_loop/message_pump_mac.h"
+#include "base/posix/eintr_wrapper.h"
+#include "chrome/utility/image_writer/error_messages.h"
+#include "chrome/utility/image_writer/image_writer.h"
+
+namespace image_writer {
+
+DiskUnmounterMac::DiskUnmounterMac(base::WeakPtr<ImageWriter> image_writer)
+    : image_writer_(image_writer),
+      original_thread_(base::MessageLoopProxy::current()),
+      cf_thread_("ImageWriterDiskArb") {
+}
+
+DiskUnmounterMac::~DiskUnmounterMac() {
+  if (disk_)
+    DADiskUnclaim(disk_);
+}
+
+void DiskUnmounterMac::Unmount(const std::string& device_path,
+                               const base::Closure& continuation) {
+  unmount_continuation_closure_ = continuation;
+
+  base::Thread::Options options;
+  options.message_pump_factory = base::Bind(&CreateMessagePump);
+
+  cf_thread_.StartWithOptions(options);
+
+  cf_thread_.message_loop()->PostTask(
+      FROM_HERE,
+      base::Bind(&DiskUnmounterMac::UnmountOnWorker,
+                 base::Unretained(this),
+                 device_path));
+}
+
+// static
+void DiskUnmounterMac::DiskClaimed(DADiskRef disk,
+                                   DADissenterRef dissenter,
+                                   void* context) {
+  DiskUnmounterMac* disk_unmounter = static_cast<DiskUnmounterMac*>(context);
+
+  if (dissenter) {
+    LOG(ERROR) << "Unable to claim disk.";
+    disk_unmounter->Error(error::kUnmountVolumes);
+    return;
+  }
+
+  DADiskUnmount(disk,
+                kDADiskUnmountOptionForce | kDADiskUnmountOptionWhole,
+                DiskUnmounted,
+                disk_unmounter);
+}
+
+// static
+DADissenterRef DiskUnmounterMac::DiskClaimRevoked(DADiskRef disk,
+                                                  void* context) {
+  CFStringRef reason = CFSTR(
+      "Hi. Sorry to bother you, but I'm busy overwriting the entire disk "
+      "here. There's nothing to claim but the smoldering ruins of bytes "
+      "that were in flash memory. Trust me, it's nothing that you want. "
+      "All the best. Toodles!");
+  return DADissenterCreate(kCFAllocatorDefault, kDAReturnBusy, reason);
+}
+
+// static
+void DiskUnmounterMac::DiskUnmounted(DADiskRef disk,
+                                     DADissenterRef dissenter,
+                                     void* context) {
+  DiskUnmounterMac* disk_unmounter = static_cast<DiskUnmounterMac*>(context);
+
+  if (dissenter) {
+    LOG(ERROR) << "Unable to unmount disk.";
+    disk_unmounter->Error(error::kUnmountVolumes);
+    return;
+  }
+
+  disk_unmounter->original_thread_->PostTask(
+      FROM_HERE, disk_unmounter->unmount_continuation_closure_);
+}
+
+void DiskUnmounterMac::UnmountOnWorker(const std::string& device_path) {
+  DCHECK(cf_thread_.message_loop() == base::MessageLoop::current());
+
+  session_.reset(DASessionCreate(NULL));
+
+  DASessionScheduleWithRunLoop(
+      session_, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
+
+  disk_.reset(DADiskCreateFromBSDName(
+      kCFAllocatorDefault, session_, device_path.c_str()));
+
+  if (!disk_) {
+    LOG(ERROR) << "Unable to get disk reference.";
+    Error(error::kUnmountVolumes);
+    return;
+  }
+
+  DADiskClaim(disk_,
+              kDADiskClaimOptionDefault,
+              DiskClaimRevoked,
+              this,
+              DiskClaimed,
+              this);
+}
+
+// static
+scoped_ptr<base::MessagePump> DiskUnmounterMac::CreateMessagePump() {
+  return scoped_ptr<base::MessagePump>(new base::MessagePumpCFRunLoop);
+}
+
+void DiskUnmounterMac::Error(const std::string& message) {
+  original_thread_->PostTask(
+      FROM_HERE, base::Bind(&ImageWriter::Error, image_writer_, message));
+}
+
+}  // namespace image_writer