[Chromoting] Handle CR-LF correctly when transferring text items to a…

…nd from the clipboard on a Windows host.

When reading from the clipboard, CR-LF pairs are replaced by LF.
When writing to the clipboard, each LF is replaced by CR-LF.

BUG=117473


Review URL: https://chromiumcodereview.appspot.com/10441131

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@140206 0039d316-1c4b-4281-b951-d872f2087c98

remoting/base/util.cc

@@ -265,4 +265,42 @@ void CopyRGB32Rect(const uint8* source_buffer,
            SkIRect::MakeWH(dest_rect.width(), dest_rect.height()));
 }
 
+std::string ReplaceLfByCrLf(const std::string& in) {
+  std::string out;
+  out.resize(2 * in.size());
+  char* out_p_begin = &out[0];
+  char* out_p = out_p_begin;
+  const char* in_p_begin = &in[0];
+  const char* in_p_end = &in[in.size()];
+  for (const char* in_p = in_p_begin; in_p < in_p_end; ++in_p) {
+    char c = *in_p;
+    if (c == '\n') {
+      *out_p++ = '\r';
+    }
+    *out_p++ = c;
+  }
+  out.resize(out_p - out_p_begin);
+  return out;
+}
+
+std::string ReplaceCrLfByLf(const std::string& in) {
+  std::string out;
+  out.resize(in.size());
+  char* out_p_begin = &out[0];
+  char* out_p = out_p_begin;
+  const char* in_p_begin = &in[0];
+  const char* in_p_end = &in[in.size()];
+  for (const char* in_p = in_p_begin; in_p < in_p_end; ++in_p) {
+    char c = *in_p;
+    if ((c == '\r') && (in_p + 1 < in_p_end) && (*(in_p + 1) == '\n')) {
+      *out_p++ = '\n';
+      ++in_p;
+    } else {
+      *out_p++ = c;
+    }
+  }
+  out.resize(out_p - out_p_begin);
+  return out;
+}
+
 }  // namespace remoting

remoting/base/util.h

@@ -82,6 +82,12 @@ void CopyRGB32Rect(const uint8* source_buffer,
                    const SkIRect& dest_buffer_rect,
                    const SkIRect& dest_rect);
 
+// Replaces every occurrence of "\n" in a string by "\r\n".
+std::string ReplaceLfByCrLf(const std::string& in);
+
+// Replaces every occurrence of "\r\n" in a string by "\n".
+std::string ReplaceCrLfByLf(const std::string& in);
+
 }  // namespace remoting
 
 #endif  // REMOTING_BASE_UTIL_H_

remoting/base/util_unittest.cc

@@ -184,4 +184,73 @@ TEST(YuvToRgbTest, ClippingAndScaling) {
   }
 }
 
+TEST(ReplaceLfByCrLfTest, Basic) {
+  EXPECT_EQ("ab", ReplaceLfByCrLf("ab"));
+  EXPECT_EQ("\r\nab", ReplaceLfByCrLf("\nab"));
+  EXPECT_EQ("\r\nab\r\n", ReplaceLfByCrLf("\nab\n"));
+  EXPECT_EQ("\r\nab\r\ncd", ReplaceLfByCrLf("\nab\ncd"));
+  EXPECT_EQ("\r\nab\r\ncd\r\n", ReplaceLfByCrLf("\nab\ncd\n"));
+  EXPECT_EQ("\r\n\r\nab\r\n\r\ncd\r\n\r\n",
+      ReplaceLfByCrLf("\n\nab\n\ncd\n\n"));
+}
+
+TEST(ReplaceLfByCrLfTest, Speed) {
+  int kLineSize = 128;
+  std::string line(kLineSize, 'a');
+  line[kLineSize - 1] = '\n';
+  // Make a 10M string.
+  int kLineNum = 10 * 1024 * 1024 / kLineSize;
+  std::string buffer;
+  buffer.resize(kLineNum * kLineSize);
+  for (int i = 0; i < kLineNum; ++i) {
+    memcpy(&buffer[i * kLineSize], &line[0], kLineSize);
+  }
+  // Convert the string.
+  buffer = ReplaceLfByCrLf(buffer);
+  // Check the converted string.
+  EXPECT_EQ(static_cast<size_t>((kLineSize + 1) * kLineNum), buffer.size());
+  const char* p = &buffer[0];
+  for (int i = 0; i < kLineNum; ++i) {
+    EXPECT_EQ(0, memcmp(&line[0], p, kLineSize - 1));
+    p += kLineSize - 1;
+    EXPECT_EQ('\r', *p++);
+    EXPECT_EQ('\n', *p++);
+  }
+}
+
+TEST(ReplaceCrLfByLfTest, Basic) {
+  EXPECT_EQ("ab", ReplaceCrLfByLf("ab"));
+  EXPECT_EQ("\nab", ReplaceCrLfByLf("\r\nab"));
+  EXPECT_EQ("\nab\n", ReplaceCrLfByLf("\r\nab\r\n"));
+  EXPECT_EQ("\nab\ncd", ReplaceCrLfByLf("\r\nab\r\ncd"));
+  EXPECT_EQ("\nab\ncd\n", ReplaceCrLfByLf("\r\nab\r\ncd\n"));
+  EXPECT_EQ("\n\nab\n\ncd\n\n",
+      ReplaceCrLfByLf("\r\n\r\nab\r\n\r\ncd\r\n\r\n"));
+  EXPECT_EQ("\rab\rcd\r", ReplaceCrLfByLf("\rab\rcd\r"));
+}
+
+TEST(ReplaceCrLfByLfTest, Speed) {
+  int kLineSize = 128;
+  std::string line(kLineSize, 'a');
+  line[kLineSize - 2] = '\r';
+  line[kLineSize - 1] = '\n';
+  // Make a 10M string.
+  int kLineNum = 10 * 1024 * 1024 / kLineSize;
+  std::string buffer;
+  buffer.resize(kLineNum * kLineSize);
+  for (int i = 0; i < kLineNum; ++i) {
+    memcpy(&buffer[i * kLineSize], &line[0], kLineSize);
+  }
+  // Convert the string.
+  buffer = ReplaceCrLfByLf(buffer);
+  // Check the converted string.
+  EXPECT_EQ(static_cast<size_t>((kLineSize - 1) * kLineNum), buffer.size());
+  const char* p = &buffer[0];
+  for (int i = 0; i < kLineNum; ++i) {
+    EXPECT_EQ(0, memcmp(&line[0], p, kLineSize - 2));
+    p += kLineSize - 2;
+    EXPECT_EQ('\n', *p++);
+  }
+}
+
 }  // namespace remoting

remoting/host/clipboard_win.cc

@@ -17,6 +17,7 @@
 #include "base/win/windows_version.h"
 #include "base/win/wrapped_window_proc.h"
 #include "remoting/base/constants.h"
+#include "remoting/base/util.h"
 #include "remoting/proto/event.pb.h"
 #include "remoting/protocol/clipboard_stub.h"
 
@@ -202,7 +203,7 @@ void ClipboardWin::InjectClipboardEvent(
   if (event.mime_type().compare(kMimeTypeTextUtf8)) {
     return;
   }
-  string16 text = UTF8ToUTF16(event.data());
+  string16 text = UTF8ToUTF16(ReplaceLfByCrLf(event.data()));
 
   ScopedClipboard clipboard;
   if (!clipboard.Init(hwnd_)) {
@@ -259,7 +260,7 @@ void ClipboardWin::OnClipboardUpdate() {
 
     protocol::ClipboardEvent event;
     event.set_mime_type(kMimeTypeTextUtf8);
-    event.set_data(UTF16ToUTF8(text));
+    event.set_data(ReplaceCrLfByLf(UTF16ToUTF8(text)));
 
     if (client_clipboard_.get()) {
       client_clipboard_->InjectClipboardEvent(event);