Checkin for CL: http://codereview.chromium.org/3061044/show...

chrome/browser/dom_ui/dom_ui_screenshot_source.cc

Index: chrome/browser/dom_ui/dom_ui_screenshot_source.cc
===================================================================
--- chrome/browser/dom_ui/dom_ui_screenshot_source.cc	(revision 0)
+++ chrome/browser/dom_ui/dom_ui_screenshot_source.cc	(revision 0)
@@ -0,0 +1,112 @@
+// Copyright (c) 2009 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/dom_ui/dom_ui_screenshot_source.h"
+
+#include "base/callback.h"
+#include "base/file_util.h"
+#include "base/path_service.h"
+#include "base/ref_counted_memory.h"
+#include "base/task.h"
+#include "base/thread.h"
+#include "base/waitable_event.h"
+#include "chrome/browser/chrome_thread.h"
+#include "chrome/common/chrome_paths.h"
+#include "chrome/common/url_constants.h"
+#include "gfx/codec/jpeg_codec.h"
+#include "googleurl/src/gurl.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+
+static const char kCurrentScreenshot[] = "current";
+#if defined(OS_CHROMEOS)
+static const char kSavedScreenshots[] = "saved/";
+#endif
+
+static const char kScreenshotsRelativePath[] = "/Screenshots/";
+
+#if defined(OS_CHROMEOS)
+// Read the file from the screenshots directory into the read_bytes vector.
+void ReadScreenshot(const std::string& filename,
+                   std::vector<unsigned char>* read_bytes,
+                   base::WaitableEvent* read_complete) {
+  read_bytes->clear();
+
+  FilePath fileshelf_path;
+  if (!PathService::Get(chrome::DIR_DEFAULT_DOWNLOADS, &fileshelf_path)) {
+    read_complete->Signal();
+    return;
+  }
+
+  FilePath file(fileshelf_path.value() + std::string(kScreenshotsRelativePath) +
+                filename);
+
+  int64 file_size = 0;
+  if (!file_util::GetFileSize(file, &file_size)) {
+    read_complete->Signal();
+    return;
+  }
+
+  // expand vector to file size
+  read_bytes->resize(file_size);
+  // read file into the vector
+  int bytes_read = 0;
+  if (!(bytes_read = file_util::ReadFile(file,
+                                         reinterpret_cast<char*>(
+                                             &read_bytes->front()),
+                                             static_cast<int>(file_size))))
+    read_bytes->clear();
+
+  // We're done, if successful, read_bytes will have the data
+  // otherwise, it'll be empty.
+  read_complete->Signal();
+}
+
+// Get a saved screenshot - read on the FILE thread.
+std::vector<unsigned char> GetSavedScreenshot(std::string filename) {
+  base::WaitableEvent read_complete(true, false);
+  std::vector<unsigned char> bytes;
+  ChromeThread::PostTask(ChromeThread::FILE, FROM_HERE,
+                         NewRunnableFunction(&ReadScreenshot, filename,
+                                             &bytes, &read_complete));
+  read_complete.Wait();
+  return bytes;
+}
+#endif
+
+std::vector<unsigned char> DOMUIScreenshotSource::GetScreenshot(
+    const std::string& path) {
+  if (path == kCurrentScreenshot) {
+    return current_screenshot_;
+#if defined(OS_CHROMEOS)
+  } else if (path.compare(0, strlen(kSavedScreenshots),
+                          kSavedScreenshots) == 0) {
+    // Split the saved screenshot filename from the path
+    std::string filename = path.substr(strlen(kSavedScreenshots));
+
+    return GetSavedScreenshot(filename);
+#endif
+  } else {
+    std::vector<unsigned char> ret;
+    // TODO(rkc): Weird vc bug, return std::vector<unsigned char>() causes
+    // the object assigned to the return value of this function magically
+    // change it's address 0x0; look into this eventually.
+    return ret;
+  }
+}
+
+DOMUIScreenshotSource::DOMUIScreenshotSource(
+    std::vector<unsigned char>* current_screenshot)
+    : DataSource(chrome::kChromeUIScreenshotPath, MessageLoop::current()) {
+  // Setup the last screenshot taken.
+  if (current_screenshot)
+    current_screenshot_ = *current_screenshot;
+  else
+    current_screenshot_.clear();
+}
+
+void DOMUIScreenshotSource::StartDataRequest(const std::string& path,
+                                            bool is_off_the_record,
+                                            int request_id) {
+  SendResponse(request_id, new RefCountedBytes(GetScreenshot(path)));
+}