diff --git a/adb/sysdeps_win32.cpp b/adb/sysdeps_win32.cpp
index e325889..0634da5 100644
--- a/adb/sysdeps_win32.cpp
+++ b/adb/sysdeps_win32.cpp
@@ -35,6 +35,7 @@
 #include <base/logging.h>
 #include <base/stringprintf.h>
 #include <base/strings.h>
+#include <base/utf8.h>
 
 #include "adb.h"
 
@@ -2546,15 +2547,14 @@
     return _get_console_handle(fd) ? 1 : 0;
 }
 
-// Read an input record from the console; one that should be processed.
-static bool _get_interesting_input_record_uncached(const HANDLE console,
-    INPUT_RECORD* const input_record) {
+// Get the next KEY_EVENT_RECORD that should be processed.
+static bool _get_key_event_record(const HANDLE console, INPUT_RECORD* const input_record) {
     for (;;) {
         DWORD read_count = 0;
         memset(input_record, 0, sizeof(*input_record));
         if (!ReadConsoleInputA(console, input_record, 1, &read_count)) {
-            D("_get_interesting_input_record_uncached: ReadConsoleInputA() "
-              "failed: %s\n", SystemErrorCodeToString(GetLastError()).c_str());
+            D("_get_key_event_record: ReadConsoleInputA() failed: %s\n",
+              SystemErrorCodeToString(GetLastError()).c_str());
             errno = EIO;
             return false;
         }
@@ -2580,28 +2580,6 @@
     }
 }
 
-// Cached input record (in case _console_read() is passed a buffer that doesn't
-// have enough space to fit wRepeatCount number of key sequences). A non-zero
-// wRepeatCount indicates that a record is cached.
-static INPUT_RECORD _win32_input_record;
-
-// Get the next KEY_EVENT_RECORD that should be processed.
-static KEY_EVENT_RECORD* _get_key_event_record(const HANDLE console) {
-    // If nothing cached, read directly from the console until we get an
-    // interesting record.
-    if (_win32_input_record.Event.KeyEvent.wRepeatCount == 0) {
-        if (!_get_interesting_input_record_uncached(console,
-            &_win32_input_record)) {
-            // There was an error, so make sure wRepeatCount is zero because
-            // that signifies no cached input record.
-            _win32_input_record.Event.KeyEvent.wRepeatCount = 0;
-            return NULL;
-        }
-    }
-
-    return &_win32_input_record.Event.KeyEvent;
-}
-
 static __inline__ bool _is_shift_pressed(const DWORD control_key_state) {
     return (control_key_state & SHIFT_PRESSED) != 0;
 }
@@ -2946,16 +2924,34 @@
     return len + 1;
 }
 
-// Writes to buffer buf (of length len), returning number of bytes written or
-// -1 on error. Never returns zero because Win32 consoles are never 'closed'
-// (as far as I can tell).
+// Internal buffer to satisfy future _console_read() calls.
+static std::vector<char> g_console_input_buffer;
+
+// Writes to buffer buf (of length len), returning number of bytes written or -1 on error. Never
+// returns zero on console closure because Win32 consoles are never 'closed' (as far as I can tell).
 static int _console_read(const HANDLE console, void* buf, size_t len) {
     for (;;) {
-        KEY_EVENT_RECORD* const key_event = _get_key_event_record(console);
-        if (key_event == NULL) {
+        // Read of zero bytes should not block waiting for something from the console.
+        if (len == 0) {
+            return 0;
+        }
+
+        // Flush as much as possible from input buffer.
+        if (!g_console_input_buffer.empty()) {
+            const int bytes_read = std::min(len, g_console_input_buffer.size());
+            memcpy(buf, g_console_input_buffer.data(), bytes_read);
+            const auto begin = g_console_input_buffer.begin();
+            g_console_input_buffer.erase(begin, begin + bytes_read);
+            return bytes_read;
+        }
+
+        // Read from the actual console. This may block until input.
+        INPUT_RECORD input_record;
+        if (!_get_key_event_record(console, &input_record)) {
             return -1;
         }
 
+        KEY_EVENT_RECORD* const key_event = &input_record.Event.KeyEvent;
         const WORD vk = key_event->wVirtualKeyCode;
         const CHAR ch = key_event->uChar.AsciiChar;
         const DWORD control_key_state = _normalize_altgr_control_key_state(
@@ -3133,7 +3129,12 @@
                 break;
 
                 case 0x32:          // 2
+                case 0x33:          // 3
+                case 0x34:          // 4
+                case 0x35:          // 5
                 case 0x36:          // 6
+                case 0x37:          // 7
+                case 0x38:          // 8
                 case VK_OEM_MINUS:  // -_
                 {
                     seqbuflen = _get_control_character(seqbuf, key_event,
@@ -3149,25 +3150,6 @@
                 }
                 break;
 
-                case 0x33:  // 3
-                case 0x34:  // 4
-                case 0x35:  // 5
-                case 0x37:  // 7
-                case 0x38:  // 8
-                {
-                    seqbuflen = _get_control_character(seqbuf, key_event,
-                        control_key_state);
-
-                    // If Alt is pressed and it isn't Ctrl-Alt-ShiftUp, then
-                    // prefix with escape.
-                    if (_is_alt_pressed(control_key_state) &&
-                        !(_is_ctrl_pressed(control_key_state) &&
-                        !_is_shift_pressed(control_key_state))) {
-                        seqbuflen = _escape_prefix(seqbuf, seqbuflen);
-                    }
-                }
-                break;
-
                 case 0x41:  // a
                 case 0x42:  // b
                 case 0x43:  // c
@@ -3296,46 +3278,15 @@
             // event.
             D("_console_read: unknown virtual key code: %d, enhanced: %s",
                 vk, _is_enhanced_key(control_key_state) ? "true" : "false");
-            key_event->wRepeatCount = 0;
             continue;
         }
 
-        int bytesRead = 0;
-
-        // put output wRepeatCount times into buf/len
-        while (key_event->wRepeatCount > 0) {
-            if (len >= outlen) {
-                // Write to buf/len
-                memcpy(buf, out, outlen);
-                buf = (void*)((char*)buf + outlen);
-                len -= outlen;
-                bytesRead += outlen;
-
-                // consume the input
-                --key_event->wRepeatCount;
-            } else {
-                // Not enough space, so just leave it in _win32_input_record
-                // for a subsequent retrieval.
-                if (bytesRead == 0) {
-                    // We didn't write anything because there wasn't enough
-                    // space to even write one sequence. This should never
-                    // happen if the caller uses sensible buffer sizes
-                    // (i.e. >= maximum sequence length which is probably a
-                    // few bytes long).
-                    D("_console_read: no buffer space to write one sequence; "
-                        "buffer: %ld, sequence: %ld\n", (long)len,
-                        (long)outlen);
-                    errno = ENOMEM;
-                    return -1;
-                } else {
-                    // Stop trying to write to buf/len, just return whatever
-                    // we wrote so far.
-                    break;
-                }
-            }
+        // put output wRepeatCount times into g_console_input_buffer
+        while (key_event->wRepeatCount-- > 0) {
+            g_console_input_buffer.insert(g_console_input_buffer.end(), out, out + outlen);
         }
 
-        return bytesRead;
+        // Loop around and try to flush g_console_input_buffer
     }
 }
 
@@ -3516,100 +3467,61 @@
     exit(-1);
 }
 
-// TODO: Consider implementing widen() and narrow() out of std::wstring_convert
-// once libcxx is supported on Windows. Or, consider libutils/Unicode.cpp.
-
-// Convert from UTF-8 to UTF-16. A size of -1 specifies a NULL terminated
-// string. Any other size specifies the number of chars to convert, excluding
-// any NULL terminator (if you're passing an explicit size, you probably don't
-// have a NULL terminated string in the first place).
-std::wstring widen(const char* utf8, const int size) {
-    // Note: Do not call SystemErrorCodeToString() from widen() because
-    // SystemErrorCodeToString() calls narrow() which may call fatal() which
-    // calls adb_vfprintf() which calls widen(), potentially causing infinite
-    // recursion.
-    const int chars_to_convert = MultiByteToWideChar(CP_UTF8, 0, utf8, size,
-                                                     NULL, 0);
-    if (chars_to_convert <= 0) {
-        // UTF-8 to UTF-16 should be lossless, so we don't expect this to fail.
-        _widen_fatal("MultiByteToWideChar failed counting: %d, "
-                     "GetLastError: %lu", chars_to_convert, GetLastError());
-    }
-
+// Convert size number of UTF-8 char's to UTF-16. Fatal exit on error.
+std::wstring widen(const char* utf8, const size_t size) {
     std::wstring utf16;
-    size_t chars_to_allocate = chars_to_convert;
-    if (size == -1) {
-        // chars_to_convert includes a NULL terminator, so subtract space
-        // for that because resize() includes that itself.
-        --chars_to_allocate;
+    if (!android::base::UTF8ToWide(utf8, size, &utf16)) {
+        // If we call fatal() here and fatal() calls widen(), then there may be
+        // infinite recursion. To avoid this, call _widen_fatal() instead.
+        _widen_fatal("cannot convert from UTF-8 to UTF-16");
     }
-    utf16.resize(chars_to_allocate);
-
-    // This uses &string[0] to get write-access to the entire string buffer
-    // which may be assuming that the chars are all contiguous, but it seems
-    // to work and saves us the hassle of using a temporary
-    // std::vector<wchar_t>.
-    const int result = MultiByteToWideChar(CP_UTF8, 0, utf8, size, &utf16[0],
-                                           chars_to_convert);
-    if (result != chars_to_convert) {
-        // UTF-8 to UTF-16 should be lossless, so we don't expect this to fail.
-        _widen_fatal("MultiByteToWideChar failed conversion: %d, "
-                     "GetLastError: %lu", result, GetLastError());
-    }
-
-    // If a size was passed in (size != -1), then the string is NULL terminated
-    // by a NULL char that was written by std::string::resize(). If size == -1,
-    // then MultiByteToWideChar() read a NULL terminator from the original
-    // string and converted it to a NULL UTF-16 char in the output.
 
     return utf16;
 }
 
-// Convert a NULL terminated string from UTF-8 to UTF-16.
+// Convert a NULL-terminated string of UTF-8 characters to UTF-16. Fatal exit
+// on error.
 std::wstring widen(const char* utf8) {
-    // Pass -1 to let widen() determine the string length.
-    return widen(utf8, -1);
-}
-
-// Convert from UTF-8 to UTF-16.
-std::wstring widen(const std::string& utf8) {
-    return widen(utf8.c_str(), utf8.length());
-}
-
-// Convert from UTF-16 to UTF-8.
-std::string narrow(const std::wstring& utf16) {
-    return narrow(utf16.c_str());
-}
-
-// Convert from UTF-16 to UTF-8.
-std::string narrow(const wchar_t* utf16) {
-    // Note: Do not call SystemErrorCodeToString() from narrow() because
-    // SystemErrorCodeToString() calls narrow() and we don't want potential
-    // infinite recursion.
-    const int chars_required = WideCharToMultiByte(CP_UTF8, 0, utf16, -1, NULL,
-                                                   0, NULL, NULL);
-    if (chars_required <= 0) {
-        // UTF-16 to UTF-8 should be lossless, so we don't expect this to fail.
-        fatal("WideCharToMultiByte failed counting: %d, GetLastError: %lu",
-              chars_required, GetLastError());
+    std::wstring utf16;
+    if (!android::base::UTF8ToWide(utf8, &utf16)) {
+        // If we call fatal() here and fatal() calls widen(), then there may be
+        // infinite recursion. To avoid this, call _widen_fatal() instead.
+        _widen_fatal("cannot convert from UTF-8 to UTF-16");
     }
 
-    std::string utf8;
-    // Subtract space for the NULL terminator because resize() includes
-    // that itself. Note that this could potentially throw a std::bad_alloc
-    // exception.
-    utf8.resize(chars_required - 1);
+    return utf16;
+}
 
-    // This uses &string[0] to get write-access to the entire string buffer
-    // which may be assuming that the chars are all contiguous, but it seems
-    // to work and saves us the hassle of using a temporary
-    // std::vector<char>.
-    const int result = WideCharToMultiByte(CP_UTF8, 0, utf16, -1, &utf8[0],
-                                           chars_required, NULL, NULL);
-    if (result != chars_required) {
-        // UTF-16 to UTF-8 should be lossless, so we don't expect this to fail.
-        fatal("WideCharToMultiByte failed conversion: %d, GetLastError: %lu",
-              result, GetLastError());
+// Convert a UTF-8 std::string (including any embedded NULL characters) to
+// UTF-16. Fatal exit on error.
+std::wstring widen(const std::string& utf8) {
+    std::wstring utf16;
+    if (!android::base::UTF8ToWide(utf8, &utf16)) {
+        // If we call fatal() here and fatal() calls widen(), then there may be
+        // infinite recursion. To avoid this, call _widen_fatal() instead.
+        _widen_fatal("cannot convert from UTF-8 to UTF-16");
+    }
+
+    return utf16;
+}
+
+// Convert a UTF-16 std::wstring (including any embedded NULL characters) to
+// UTF-8. Fatal exit on error.
+std::string narrow(const std::wstring& utf16) {
+    std::string utf8;
+    if (!android::base::WideToUTF8(utf16, &utf8)) {
+        fatal("cannot convert from UTF-16 to UTF-8");
+    }
+
+    return utf8;
+}
+
+// Convert a NULL-terminated string of UTF-16 characters to UTF-8. Fatal exit
+// on error.
+std::string narrow(const wchar_t* utf16) {
+    std::string utf8;
+    if (!android::base::WideToUTF8(utf16, &utf8)) {
+        fatal("cannot convert from UTF-16 to UTF-8");
     }
 
     return utf8;
@@ -3752,9 +3664,12 @@
 // on error.
 static int _console_write_utf8(const char* buf, size_t size, FILE* stream,
                                HANDLE console) {
-    // Convert from UTF-8 to UTF-16.
+    std::wstring output;
+
+    // Try to convert from data that might be UTF-8 to UTF-16, ignoring errors.
+    // Data might not be UTF-8 if the user cat's random data, runs dmesg, etc.
     // This could throw std::bad_alloc.
-    const std::wstring output(widen(buf, size));
+    (void)android::base::UTF8ToWide(buf, size, &output);
 
     // Note that this does not do \n => \r\n translation because that
     // doesn't seem necessary for the Windows console. For the Windows
diff --git a/base/Android.mk b/base/Android.mk
index 613636b..4e6bd10 100644
--- a/base/Android.mk
+++ b/base/Android.mk
@@ -23,6 +23,9 @@
     strings.cpp \
     test_utils.cpp \
 
+libbase_windows_src_files := \
+    utf8.cpp \
+
 libbase_test_src_files := \
     file_test.cpp \
     logging_test.cpp \
@@ -31,6 +34,9 @@
     strings_test.cpp \
     test_main.cpp \
 
+libbase_test_windows_src_files := \
+    utf8_test.cpp \
+
 libbase_cppflags := \
     -Wall \
     -Wextra \
@@ -42,6 +48,9 @@
 LOCAL_MODULE := libbase
 LOCAL_CLANG := true
 LOCAL_SRC_FILES := $(libbase_src_files)
+LOCAL_SRC_FILES_darwin := $(libbase_darwin_src_files)
+LOCAL_SRC_FILES_linux := $(libbase_linux_src_files)
+LOCAL_SRC_FILES_windows := $(libbase_windows_src_files)
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
 LOCAL_CPPFLAGS := $(libbase_cppflags)
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
@@ -64,6 +73,9 @@
 include $(CLEAR_VARS)
 LOCAL_MODULE := libbase
 LOCAL_SRC_FILES := $(libbase_src_files)
+LOCAL_SRC_FILES_darwin := $(libbase_darwin_src_files)
+LOCAL_SRC_FILES_linux := $(libbase_linux_src_files)
+LOCAL_SRC_FILES_windows := $(libbase_windows_src_files)
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
 LOCAL_CPPFLAGS := $(libbase_cppflags)
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
@@ -88,6 +100,9 @@
 LOCAL_MODULE := libbase_test
 LOCAL_CLANG := true
 LOCAL_SRC_FILES := $(libbase_test_src_files)
+LOCAL_SRC_FILES_darwin := $(libbase_test_darwin_src_files)
+LOCAL_SRC_FILES_linux := $(libbase_test_linux_src_files)
+LOCAL_SRC_FILES_windows := $(libbase_test_windows_src_files)
 LOCAL_C_INCLUDES := $(LOCAL_PATH)
 LOCAL_CPPFLAGS := $(libbase_cppflags)
 LOCAL_SHARED_LIBRARIES := libbase
@@ -100,6 +115,9 @@
 LOCAL_MODULE := libbase_test
 LOCAL_MODULE_HOST_OS := darwin linux windows
 LOCAL_SRC_FILES := $(libbase_test_src_files)
+LOCAL_SRC_FILES_darwin := $(libbase_test_darwin_src_files)
+LOCAL_SRC_FILES_linux := $(libbase_test_linux_src_files)
+LOCAL_SRC_FILES_windows := $(libbase_test_windows_src_files)
 LOCAL_C_INCLUDES := $(LOCAL_PATH)
 LOCAL_CPPFLAGS := $(libbase_cppflags)
 LOCAL_SHARED_LIBRARIES := libbase
diff --git a/base/file.cpp b/base/file.cpp
index 3468dcf..7b5e7b1 100644
--- a/base/file.cpp
+++ b/base/file.cpp
@@ -24,6 +24,7 @@
 #include <string>
 
 #include "base/macros.h"  // For TEMP_FAILURE_RETRY on Darwin.
+#include "base/utf8.h"
 #define LOG_TAG "base.file"
 #include "cutils/log.h"
 #include "utils/Compat.h"
@@ -35,6 +36,9 @@
 namespace android {
 namespace base {
 
+// Versions of standard library APIs that support UTF-8 strings.
+using namespace android::base::utf8;
+
 bool ReadFdToString(int fd, std::string* content) {
   content->clear();
 
diff --git a/base/include/base/utf8.h b/base/include/base/utf8.h
new file mode 100755
index 0000000..3cc168d
--- /dev/null
+++ b/base/include/base/utf8.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef BASE_UTF8_H
+#define BASE_UTF8_H
+
+#ifdef _WIN32
+#include <string>
+#endif
+
+namespace android {
+namespace base {
+
+// Only available on Windows because this is only needed on Windows.
+#ifdef _WIN32
+// Convert size number of UTF-16 wchar_t's to UTF-8. Returns whether the
+// conversion was done successfully.
+bool WideToUTF8(const wchar_t* utf16, const size_t size, std::string* utf8);
+
+// Convert a NULL-terminated string of UTF-16 characters to UTF-8. Returns
+// whether the conversion was done successfully.
+bool WideToUTF8(const wchar_t* utf16, std::string* utf8);
+
+// Convert a UTF-16 std::wstring (including any embedded NULL characters) to
+// UTF-8. Returns whether the conversion was done successfully.
+bool WideToUTF8(const std::wstring& utf16, std::string* utf8);
+
+// Convert size number of UTF-8 char's to UTF-16. Returns whether the conversion
+// was done successfully.
+bool UTF8ToWide(const char* utf8, const size_t size, std::wstring* utf16);
+
+// Convert a NULL-terminated string of UTF-8 characters to UTF-16. Returns
+// whether the conversion was done successfully.
+bool UTF8ToWide(const char* utf8, std::wstring* utf16);
+
+// Convert a UTF-8 std::string (including any embedded NULL characters) to
+// UTF-16. Returns whether the conversion was done successfully.
+bool UTF8ToWide(const std::string& utf8, std::wstring* utf16);
+#endif
+
+// The functions in the utf8 namespace take UTF-8 strings. For Windows, these
+// are wrappers, for non-Windows these just expose existing APIs. To call these
+// functions, use:
+//
+// // anonymous namespace to avoid conflict with existing open(), unlink(), etc.
+// namespace {
+//   // Import functions into anonymous namespace.
+//   using namespace android::base::utf8;
+//
+//   void SomeFunction(const char* name) {
+//     int fd = open(name, ...);  // Calls android::base::utf8::open().
+//     ...
+//     unlink(name);              // Calls android::base::utf8::unlink().
+//   }
+// }
+namespace utf8 {
+
+#ifdef _WIN32
+int open(const char* name, int flags, ...);
+int unlink(const char* name);
+#else
+using ::open;
+using ::unlink;
+#endif
+
+}  // namespace utf8
+}  // namespace base
+}  // namespace android
+
+#endif  // BASE_UTF8_H
diff --git a/base/logging.cpp b/base/logging.cpp
index 248cd06..01a046a 100644
--- a/base/logging.cpp
+++ b/base/logging.cpp
@@ -53,6 +53,33 @@
 #include <unistd.h>
 #endif
 
+// For gettid.
+#if defined(__APPLE__)
+#include "AvailabilityMacros.h"  // For MAC_OS_X_VERSION_MAX_ALLOWED
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/syscall.h>
+#include <sys/time.h>
+#include <unistd.h>
+#elif defined(__linux__) && !defined(__ANDROID__)
+#include <syscall.h>
+#include <unistd.h>
+#elif defined(_WIN32)
+#include <windows.h>
+#endif
+
+static pid_t GetThreadId() {
+#if defined(__BIONIC__)
+  return gettid();
+#elif defined(__APPLE__)
+  return syscall(SYS_thread_selfid);
+#elif defined(__linux__)
+  return syscall(__NR_gettid);
+#elif defined(_WIN32)
+  return GetCurrentThreadId();
+#endif
+}
+
 namespace {
 #ifndef _WIN32
 using std::mutex;
@@ -158,7 +185,7 @@
                 "Mismatch in size of log_characters and values in LogSeverity");
   char severity_char = log_characters[severity];
   fprintf(stderr, "%s %c %5d %5d %s:%u] %s\n", ProgramInvocationName(),
-          severity_char, getpid(), gettid(), file, line, message);
+          severity_char, getpid(), GetThreadId(), file, line, message);
 }
 
 
diff --git a/base/utf8.cpp b/base/utf8.cpp
new file mode 100755
index 0000000..62a118f
--- /dev/null
+++ b/base/utf8.cpp
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <windows.h>
+
+#include "base/utf8.h"
+
+#include <fcntl.h>
+
+#include <string>
+
+#include "base/logging.h"
+
+namespace android {
+namespace base {
+
+bool WideToUTF8(const wchar_t* utf16, const size_t size, std::string* utf8) {
+  utf8->clear();
+
+  if (size == 0) {
+    return true;
+  }
+
+  // TODO: Consider using std::wstring_convert once libcxx is supported on
+  // Windows.
+
+  // Only Vista or later has this flag that causes WideCharToMultiByte() to
+  // return an error on invalid characters.
+  const DWORD flags =
+#if (WINVER >= 0x0600)
+    WC_ERR_INVALID_CHARS;
+#else
+    0;
+#endif
+
+  const int chars_required = WideCharToMultiByte(CP_UTF8, flags, utf16, size,
+                                                 NULL, 0, NULL, NULL);
+  if (chars_required <= 0) {
+    return false;
+  }
+
+  // This could potentially throw a std::bad_alloc exception.
+  utf8->resize(chars_required);
+
+  const int result = WideCharToMultiByte(CP_UTF8, flags, utf16, size,
+                                         &(*utf8)[0], chars_required, NULL,
+                                         NULL);
+  if (result != chars_required) {
+    CHECK_LE(result, chars_required) << "WideCharToMultiByte wrote " << result
+        << " chars to buffer of " << chars_required << " chars";
+    utf8->clear();
+    return false;
+  }
+
+  return true;
+}
+
+bool WideToUTF8(const wchar_t* utf16, std::string* utf8) {
+  // Compute string length of NULL-terminated string with wcslen().
+  return WideToUTF8(utf16, wcslen(utf16), utf8);
+}
+
+bool WideToUTF8(const std::wstring& utf16, std::string* utf8) {
+  // Use the stored length of the string which allows embedded NULL characters
+  // to be converted.
+  return WideToUTF8(utf16.c_str(), utf16.length(), utf8);
+}
+
+// Internal helper function that takes MultiByteToWideChar() flags.
+static bool _UTF8ToWideWithFlags(const char* utf8, const size_t size,
+                                 std::wstring* utf16, const DWORD flags) {
+  utf16->clear();
+
+  if (size == 0) {
+    return true;
+  }
+
+  // TODO: Consider using std::wstring_convert once libcxx is supported on
+  // Windows.
+  const int chars_required = MultiByteToWideChar(CP_UTF8, flags, utf8, size,
+                                                 NULL, 0);
+  if (chars_required <= 0) {
+    return false;
+  }
+
+  // This could potentially throw a std::bad_alloc exception.
+  utf16->resize(chars_required);
+
+  const int result = MultiByteToWideChar(CP_UTF8, flags, utf8, size,
+                                         &(*utf16)[0], chars_required);
+  if (result != chars_required) {
+    CHECK_LE(result, chars_required) << "MultiByteToWideChar wrote " << result
+        << " chars to buffer of " << chars_required << " chars";
+    utf16->clear();
+    return false;
+  }
+
+  return true;
+}
+
+bool UTF8ToWide(const char* utf8, const size_t size, std::wstring* utf16) {
+  // If strictly interpreting as UTF-8 succeeds, return success.
+  if (_UTF8ToWideWithFlags(utf8, size, utf16, MB_ERR_INVALID_CHARS)) {
+    return true;
+  }
+
+  // Fallback to non-strict interpretation, allowing invalid characters and
+  // converting as best as possible, and return false to signify a problem.
+  (void)_UTF8ToWideWithFlags(utf8, size, utf16, 0);
+  return false;
+}
+
+bool UTF8ToWide(const char* utf8, std::wstring* utf16) {
+  // Compute string length of NULL-terminated string with strlen().
+  return UTF8ToWide(utf8, strlen(utf8), utf16);
+}
+
+bool UTF8ToWide(const std::string& utf8, std::wstring* utf16) {
+  // Use the stored length of the string which allows embedded NULL characters
+  // to be converted.
+  return UTF8ToWide(utf8.c_str(), utf8.length(), utf16);
+}
+
+// Versions of standard library APIs that support UTF-8 strings.
+namespace utf8 {
+
+int open(const char* name, int flags, ...) {
+  std::wstring name_utf16;
+  if (!UTF8ToWide(name, &name_utf16)) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  int mode = 0;
+  if ((flags & O_CREAT) != 0) {
+    va_list args;
+    va_start(args, flags);
+    mode = va_arg(args, int);
+    va_end(args);
+  }
+
+  return _wopen(name_utf16.c_str(), flags, mode);
+}
+
+int unlink(const char* name) {
+  std::wstring name_utf16;
+  if (!UTF8ToWide(name, &name_utf16)) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  return _wunlink(name_utf16.c_str());
+}
+
+}  // namespace utf8
+}  // namespace base
+}  // namespace android
diff --git a/base/utf8_test.cpp b/base/utf8_test.cpp
new file mode 100755
index 0000000..bbb54b1
--- /dev/null
+++ b/base/utf8_test.cpp
@@ -0,0 +1,402 @@
+/*
+* Copyright (C) 2015 The Android Open Source Project
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include "base/utf8.h"
+
+#include <gtest/gtest.h>
+
+#include "base/macros.h"
+
+namespace android {
+namespace base {
+
+TEST(UTFStringConversionsTest, ConvertInvalidUTF8) {
+  std::wstring wide;
+
+  // Standalone \xa2 is an invalid UTF-8 sequence, so this should return an
+  // error. Concatenate two C/C++ literal string constants to prevent the
+  // compiler from giving an error about "\xa2af" containing a "hex escape
+  // sequence out of range".
+  EXPECT_FALSE(android::base::UTF8ToWide("before\xa2" "after", &wide));
+
+  // Even if an invalid character is encountered, UTF8ToWide() should still do
+  // its best to convert the rest of the string. sysdeps_win32.cpp:
+  // _console_write_utf8() depends on this behavior.
+  //
+  // Thus, we verify that the valid characters are converted, but we ignore the
+  // specific replacement character that UTF8ToWide() may replace the invalid
+  // UTF-8 characters with because we want to allow that to change if the
+  // implementation changes.
+  EXPECT_EQ(0, wide.find(L"before"));
+  const wchar_t after_wide[] = L"after";
+  EXPECT_EQ(wide.length() - (arraysize(after_wide) - 1), wide.find(after_wide));
+}
+
+// Below is adapted from https://chromium.googlesource.com/chromium/src/+/master/base/strings/utf_string_conversions_unittest.cc
+
+// Copyright (c) 2010 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.
+
+// The tests below from utf_string_conversions_unittest.cc check for this
+// preprocessor symbol, so define it, as it is appropriate for Windows.
+#define WCHAR_T_IS_UTF16
+static_assert(sizeof(wchar_t) == 2, "wchar_t is not 2 bytes");
+
+// The tests below from utf_string_conversions_unittest.cc call versions of
+// UTF8ToWide() and WideToUTF8() that don't return success/failure, so these are
+// stub implementations with that signature. These are just for testing and
+// should not be moved to base because they assert/expect no errors which is
+// probably not a good idea (or at least it is something that should be left
+// up to the caller, not a base library).
+
+static std::wstring UTF8ToWide(const std::string& utf8) {
+  std::wstring utf16;
+  EXPECT_TRUE(UTF8ToWide(utf8, &utf16));
+  return utf16;
+}
+
+static std::string WideToUTF8(const std::wstring& utf16) {
+  std::string utf8;
+  EXPECT_TRUE(WideToUTF8(utf16, &utf8));
+  return utf8;
+}
+
+namespace {
+
+const wchar_t* const kConvertRoundtripCases[] = {
+  L"Google Video",
+  // "网页 图片 资讯更多 »"
+  L"\x7f51\x9875\x0020\x56fe\x7247\x0020\x8d44\x8baf\x66f4\x591a\x0020\x00bb",
+  //  "Παγκόσμιος Ιστός"
+  L"\x03a0\x03b1\x03b3\x03ba\x03cc\x03c3\x03bc\x03b9"
+  L"\x03bf\x03c2\x0020\x0399\x03c3\x03c4\x03cc\x03c2",
+  // "Поиск страниц на русском"
+  L"\x041f\x043e\x0438\x0441\x043a\x0020\x0441\x0442"
+  L"\x0440\x0430\x043d\x0438\x0446\x0020\x043d\x0430"
+  L"\x0020\x0440\x0443\x0441\x0441\x043a\x043e\x043c",
+  // "전체서비스"
+  L"\xc804\xccb4\xc11c\xbe44\xc2a4",
+
+  // Test characters that take more than 16 bits. This will depend on whether
+  // wchar_t is 16 or 32 bits.
+#if defined(WCHAR_T_IS_UTF16)
+  L"\xd800\xdf00",
+  // ?????  (Mathematical Alphanumeric Symbols (U+011d40 - U+011d44 : A,B,C,D,E)
+  L"\xd807\xdd40\xd807\xdd41\xd807\xdd42\xd807\xdd43\xd807\xdd44",
+#elif defined(WCHAR_T_IS_UTF32)
+  L"\x10300",
+  // ?????  (Mathematical Alphanumeric Symbols (U+011d40 - U+011d44 : A,B,C,D,E)
+  L"\x11d40\x11d41\x11d42\x11d43\x11d44",
+#endif
+};
+
+}  // namespace
+
+TEST(UTFStringConversionsTest, ConvertUTF8AndWide) {
+  // we round-trip all the wide strings through UTF-8 to make sure everything
+  // agrees on the conversion. This uses the stream operators to test them
+  // simultaneously.
+  for (size_t i = 0; i < arraysize(kConvertRoundtripCases); ++i) {
+    std::ostringstream utf8;
+    utf8 << WideToUTF8(kConvertRoundtripCases[i]);
+    std::wostringstream wide;
+    wide << UTF8ToWide(utf8.str());
+
+    EXPECT_EQ(kConvertRoundtripCases[i], wide.str());
+  }
+}
+
+TEST(UTFStringConversionsTest, ConvertUTF8AndWideEmptyString) {
+  // An empty std::wstring should be converted to an empty std::string,
+  // and vice versa.
+  std::wstring wempty;
+  std::string empty;
+  EXPECT_EQ(empty, WideToUTF8(wempty));
+  EXPECT_EQ(wempty, UTF8ToWide(empty));
+}
+
+TEST(UTFStringConversionsTest, ConvertUTF8ToWide) {
+  struct UTF8ToWideCase {
+    const char* utf8;
+    const wchar_t* wide;
+    bool success;
+  } convert_cases[] = {
+    // Regular UTF-8 input.
+    {"\xe4\xbd\xa0\xe5\xa5\xbd", L"\x4f60\x597d", true},
+    // Non-character is passed through.
+    {"\xef\xbf\xbfHello", L"\xffffHello", true},
+    // Truncated UTF-8 sequence.
+    {"\xe4\xa0\xe5\xa5\xbd", L"\xfffd\x597d", false},
+    // Truncated off the end.
+    {"\xe5\xa5\xbd\xe4\xa0", L"\x597d\xfffd", false},
+    // Non-shortest-form UTF-8.
+    {"\xf0\x84\xbd\xa0\xe5\xa5\xbd", L"\xfffd\x597d", false},
+    // This UTF-8 character decodes to a UTF-16 surrogate, which is illegal.
+    // Note that for whatever reason, this test fails on Windows XP.
+    {"\xed\xb0\x80", L"\xfffd", false},
+    // Non-BMP characters. The second is a non-character regarded as valid.
+    // The result will either be in UTF-16 or UTF-32.
+#if defined(WCHAR_T_IS_UTF16)
+    {"A\xF0\x90\x8C\x80z", L"A\xd800\xdf00z", true},
+    {"A\xF4\x8F\xBF\xBEz", L"A\xdbff\xdffez", true},
+#elif defined(WCHAR_T_IS_UTF32)
+    {"A\xF0\x90\x8C\x80z", L"A\x10300z", true},
+    {"A\xF4\x8F\xBF\xBEz", L"A\x10fffez", true},
+#endif
+  };
+
+  for (size_t i = 0; i < arraysize(convert_cases); i++) {
+    std::wstring converted;
+    const bool success = UTF8ToWide(convert_cases[i].utf8,
+                                    strlen(convert_cases[i].utf8),
+                                    &converted);
+    EXPECT_EQ(convert_cases[i].success, success);
+    // The original test always compared expected and converted, but don't do
+    // that because our implementation of UTF8ToWide() does not guarantee to
+    // produce the same output in error situations.
+    if (success) {
+      std::wstring expected(convert_cases[i].wide);
+      EXPECT_EQ(expected, converted);
+    }
+  }
+
+  // Manually test an embedded NULL.
+  std::wstring converted;
+  EXPECT_TRUE(UTF8ToWide("\00Z\t", 3, &converted));
+  ASSERT_EQ(3U, converted.length());
+  EXPECT_EQ(static_cast<wchar_t>(0), converted[0]);
+  EXPECT_EQ('Z', converted[1]);
+  EXPECT_EQ('\t', converted[2]);
+
+  // Make sure that conversion replaces, not appends.
+  EXPECT_TRUE(UTF8ToWide("B", 1, &converted));
+  ASSERT_EQ(1U, converted.length());
+  EXPECT_EQ('B', converted[0]);
+}
+
+#if defined(WCHAR_T_IS_UTF16)
+// This test is only valid when wchar_t == UTF-16.
+TEST(UTFStringConversionsTest, ConvertUTF16ToUTF8) {
+  struct WideToUTF8Case {
+    const wchar_t* utf16;
+    const char* utf8;
+    bool success;
+  } convert_cases[] = {
+    // Regular UTF-16 input.
+    {L"\x4f60\x597d", "\xe4\xbd\xa0\xe5\xa5\xbd", true},
+    // Test a non-BMP character.
+    {L"\xd800\xdf00", "\xF0\x90\x8C\x80", true},
+    // Non-characters are passed through.
+    {L"\xffffHello", "\xEF\xBF\xBFHello", true},
+    {L"\xdbff\xdffeHello", "\xF4\x8F\xBF\xBEHello", true},
+    // The first character is a truncated UTF-16 character.
+    // Note that for whatever reason, this test fails on Windows XP.
+    {L"\xd800\x597d", "\xef\xbf\xbd\xe5\xa5\xbd",
+#if (WINVER >= 0x0600)
+    // Only Vista and later has a new API/flag that correctly returns false.
+    false
+#else
+    true
+#endif
+    },
+    // Truncated at the end.
+    // Note that for whatever reason, this test fails on Windows XP.
+    {L"\x597d\xd800", "\xe5\xa5\xbd\xef\xbf\xbd",
+#if (WINVER >= 0x0600)
+    // Only Vista and later has a new API/flag that correctly returns false.
+    false
+#else
+    true
+#endif
+    },
+  };
+
+  for (size_t i = 0; i < arraysize(convert_cases); i++) {
+    std::string converted;
+    const bool success = WideToUTF8(convert_cases[i].utf16,
+                                    wcslen(convert_cases[i].utf16),
+                                    &converted);
+    EXPECT_EQ(convert_cases[i].success, success);
+    // The original test always compared expected and converted, but don't do
+    // that because our implementation of WideToUTF8() does not guarantee to
+    // produce the same output in error situations.
+    if (success) {
+      std::string expected(convert_cases[i].utf8);
+      EXPECT_EQ(expected, converted);
+    }
+  }
+}
+
+#elif defined(WCHAR_T_IS_UTF32)
+// This test is only valid when wchar_t == UTF-32.
+TEST(UTFStringConversionsTest, ConvertUTF32ToUTF8) {
+  struct WideToUTF8Case {
+    const wchar_t* utf32;
+    const char* utf8;
+    bool success;
+  } convert_cases[] = {
+    // Regular 16-bit input.
+    {L"\x4f60\x597d", "\xe4\xbd\xa0\xe5\xa5\xbd", true},
+    // Test a non-BMP character.
+    {L"A\x10300z", "A\xF0\x90\x8C\x80z", true},
+    // Non-characters are passed through.
+    {L"\xffffHello", "\xEF\xBF\xBFHello", true},
+    {L"\x10fffeHello", "\xF4\x8F\xBF\xBEHello", true},
+    // Invalid Unicode code points.
+    {L"\xfffffffHello", "\xEF\xBF\xBDHello", false},
+    // The first character is a truncated UTF-16 character.
+    {L"\xd800\x597d", "\xef\xbf\xbd\xe5\xa5\xbd", false},
+    {L"\xdc01Hello", "\xef\xbf\xbdHello", false},
+  };
+
+  for (size_t i = 0; i < arraysize(convert_cases); i++) {
+    std::string converted;
+    EXPECT_EQ(convert_cases[i].success,
+              WideToUTF8(convert_cases[i].utf32,
+                         wcslen(convert_cases[i].utf32),
+                         &converted));
+    std::string expected(convert_cases[i].utf8);
+    EXPECT_EQ(expected, converted);
+  }
+}
+#endif  // defined(WCHAR_T_IS_UTF32)
+
+// The test below uses these types and functions, so just do enough to get the
+// test running.
+typedef wchar_t char16;
+typedef std::wstring string16;
+
+template<typename T>
+static void* WriteInto(T* t, size_t size) {
+  // std::(w)string::resize() already includes space for a NULL terminator.
+  t->resize(size - 1);
+  return &(*t)[0];
+}
+
+// A stub implementation that calls a helper from above, just to get the test
+// below working. This is just for testing and should not be moved to base
+// because this ignores errors which is probably not a good idea, plus it takes
+// a string16 type which we don't really have.
+static std::string UTF16ToUTF8(const string16& utf16) {
+  return WideToUTF8(utf16);
+}
+
+TEST(UTFStringConversionsTest, ConvertMultiString) {
+  static char16 multi16[] = {
+    'f', 'o', 'o', '\0',
+    'b', 'a', 'r', '\0',
+    'b', 'a', 'z', '\0',
+    '\0'
+  };
+  static char multi[] = {
+    'f', 'o', 'o', '\0',
+    'b', 'a', 'r', '\0',
+    'b', 'a', 'z', '\0',
+    '\0'
+  };
+  string16 multistring16;
+  memcpy(WriteInto(&multistring16, arraysize(multi16)), multi16,
+                   sizeof(multi16));
+  EXPECT_EQ(arraysize(multi16) - 1, multistring16.length());
+  std::string expected;
+  memcpy(WriteInto(&expected, arraysize(multi)), multi, sizeof(multi));
+  EXPECT_EQ(arraysize(multi) - 1, expected.length());
+  const std::string& converted = UTF16ToUTF8(multistring16);
+  EXPECT_EQ(arraysize(multi) - 1, converted.length());
+  EXPECT_EQ(expected, converted);
+}
+
+// The tests below from sys_string_conversions_unittest.cc call SysWideToUTF8()
+// and SysUTF8ToWide(), so these are stub implementations that call the helpers
+// above. These are just for testing and should not be moved to base because
+// they ignore errors which is probably not a good idea.
+
+static std::string SysWideToUTF8(const std::wstring& utf16) {
+  return WideToUTF8(utf16);
+}
+
+static std::wstring SysUTF8ToWide(const std::string& utf8) {
+  return UTF8ToWide(utf8);
+}
+
+// Below is adapted from https://chromium.googlesource.com/chromium/src/+/master/base/strings/sys_string_conversions_unittest.cc
+
+// Copyright (c) 2011 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.
+
+#ifdef WCHAR_T_IS_UTF32
+static const std::wstring kSysWideOldItalicLetterA = L"\x10300";
+#else
+static const std::wstring kSysWideOldItalicLetterA = L"\xd800\xdf00";
+#endif
+
+TEST(SysStrings, SysWideToUTF8) {
+  EXPECT_EQ("Hello, world", SysWideToUTF8(L"Hello, world"));
+  EXPECT_EQ("\xe4\xbd\xa0\xe5\xa5\xbd", SysWideToUTF8(L"\x4f60\x597d"));
+
+  // >16 bits
+  EXPECT_EQ("\xF0\x90\x8C\x80", SysWideToUTF8(kSysWideOldItalicLetterA));
+
+  // Error case. When Windows finds a UTF-16 character going off the end of
+  // a string, it just converts that literal value to UTF-8, even though this
+  // is invalid.
+  //
+  // This is what XP does, but Vista has different behavior, so we don't bother
+  // verifying it:
+  // EXPECT_EQ("\xE4\xBD\xA0\xED\xA0\x80zyxw",
+  //           SysWideToUTF8(L"\x4f60\xd800zyxw"));
+
+  // Test embedded NULLs.
+  std::wstring wide_null(L"a");
+  wide_null.push_back(0);
+  wide_null.push_back('b');
+
+  std::string expected_null("a");
+  expected_null.push_back(0);
+  expected_null.push_back('b');
+
+  EXPECT_EQ(expected_null, SysWideToUTF8(wide_null));
+}
+
+TEST(SysStrings, SysUTF8ToWide) {
+  EXPECT_EQ(L"Hello, world", SysUTF8ToWide("Hello, world"));
+  EXPECT_EQ(L"\x4f60\x597d", SysUTF8ToWide("\xe4\xbd\xa0\xe5\xa5\xbd"));
+  // >16 bits
+  EXPECT_EQ(kSysWideOldItalicLetterA, SysUTF8ToWide("\xF0\x90\x8C\x80"));
+
+  // Error case. When Windows finds an invalid UTF-8 character, it just skips
+  // it. This seems weird because it's inconsistent with the reverse conversion.
+  //
+  // This is what XP does, but Vista has different behavior, so we don't bother
+  // verifying it:
+  // EXPECT_EQ(L"\x4f60zyxw", SysUTF8ToWide("\xe4\xbd\xa0\xe5\xa5zyxw"));
+
+  // Test embedded NULLs.
+  std::string utf8_null("a");
+  utf8_null.push_back(0);
+  utf8_null.push_back('b');
+
+  std::wstring expected_null(L"a");
+  expected_null.push_back(0);
+  expected_null.push_back('b');
+
+  EXPECT_EQ(expected_null, SysUTF8ToWide(utf8_null));
+}
+
+}  // namespace base
+}  // namespace android
diff --git a/fastboot/Android.mk b/fastboot/Android.mk
index 3f201ec..7a7366e 100644
--- a/fastboot/Android.mk
+++ b/fastboot/Android.mk
@@ -49,7 +49,7 @@
     libutils \
     liblog \
     libz \
-    libbase
+    libbase \
 
 LOCAL_STATIC_LIBRARIES_darwin := libselinux
 LOCAL_STATIC_LIBRARIES_linux := libselinux
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index be30d81..b9d03e5 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -1017,6 +1017,11 @@
         }
         partition_size = size_override;
     }
+    // Some bootloaders (angler, for example), send spurious leading whitespace.
+    partition_size = android::base::Trim(partition_size);
+    // Some bootloaders (hammerhead, for example) use implicit hex.
+    // This code used to use strtol with base 16.
+    if (!android::base::StartsWith(partition_size, "0x")) partition_size = "0x" + partition_size;
 
     gen = fs_get_generator(partition_type);
     if (!gen) {
@@ -1030,10 +1035,6 @@
         return;
     }
 
-    // Some bootloaders (hammerhead, for example) use implicit hex.
-    // This code used to use strtol with base 16.
-    if (!android::base::StartsWith(partition_size, "0x")) partition_size = "0x" + partition_size;
-
     int64_t size;
     if (!android::base::ParseInt(partition_size.c_str(), &size)) {
         fprintf(stderr, "Couldn't parse partition size '%s'.\n", partition_size.c_str());
diff --git a/metricsd/metrics_daemon.rc b/metricsd/metrics_daemon.rc
index 0ee577e..8b24749 100644
--- a/metricsd/metrics_daemon.rc
+++ b/metricsd/metrics_daemon.rc
@@ -1,7 +1,7 @@
 on post-fs-data
     mkdir /data/misc/metrics 0770 system system
 
-service metrics_daemon /system/bin/metrics_daemon --uploader -nodaemon
+service metrics_daemon /system/bin/metrics_daemon --uploader --foreground --logtosyslog
     class late_start
     user system
     group system dbus inet
diff --git a/metricsd/metrics_daemon_main.cc b/metricsd/metrics_daemon_main.cc
index 50c279d..8573f68 100644
--- a/metricsd/metrics_daemon_main.cc
+++ b/metricsd/metrics_daemon_main.cc
@@ -53,7 +53,7 @@
 }
 
 int main(int argc, char** argv) {
-  DEFINE_bool(daemon, true, "run as daemon (use -nodaemon for debugging)");
+  DEFINE_bool(foreground, false, "Don't daemonize");
 
   // The uploader is disabled by default on ChromeOS as Chrome is responsible
   // for sending the metrics.
@@ -79,13 +79,28 @@
                 metrics::kMetricsDirectory,
                 "Root of the configuration files (testing only)");
 
+  DEFINE_bool(logtostderr, false, "Log to standard error");
+  DEFINE_bool(logtosyslog, false, "Log to syslog");
+
   brillo::FlagHelper::Init(argc, argv, "Chromium OS Metrics Daemon");
 
-  // Also log to stderr when not running as daemon.
-  brillo::InitLog(brillo::kLogToSyslog | brillo::kLogHeader |
-                  (FLAGS_daemon ? 0 : brillo::kLogToStderr));
+  int logging_location = (FLAGS_foreground ? brillo::kLogToStderr
+                          : brillo::kLogToSyslog);
+  if (FLAGS_logtosyslog)
+    logging_location = brillo::kLogToSyslog;
 
-  if (FLAGS_daemon && daemon(0, 0) != 0) {
+  if (FLAGS_logtostderr)
+    logging_location = brillo::kLogToStderr;
+
+  // Also log to stderr when not running as daemon.
+  brillo::InitLog(logging_location | brillo::kLogHeader);
+
+  if (FLAGS_logtostderr && FLAGS_logtosyslog) {
+    LOG(ERROR) << "only one of --logtosyslog and --logtostderr can be set";
+    return 1;
+  }
+
+  if (!FLAGS_foreground && daemon(0, 0) != 0) {
     return errno;
   }