[icu] Support loading data file from default location

src/icu_util.cc

 // Copyright 2013 the V8 project 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 "src/icu_util.h"
 
 #if defined(_WIN32)
 #include <windows.h>
 #endif
 
 #if defined(V8_I18N_SUPPORT)
 #include <stdio.h>
 #include <stdlib.h>
 
 #include "unicode/putil.h"
 #include "unicode/udata.h"
 
+#include "src/base/file-utils.h"
+
 #define ICU_UTIL_DATA_FILE   0
 #define ICU_UTIL_DATA_SHARED 1
 #define ICU_UTIL_DATA_STATIC 2
 
 #define ICU_UTIL_DATA_SYMBOL "icudt" U_ICU_VERSION_SHORT "_dat"
 #define ICU_UTIL_DATA_SHARED_MODULE_NAME "icudt.dll"
 #endif
 
 namespace v8 {
 
 namespace internal {
 
 #if defined(V8_I18N_SUPPORT) && (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE)
 namespace {
 char* g_icu_data_ptr = NULL;
 
 void free_icu_data_ptr() {
   delete[] g_icu_data_ptr;
 }
 
 }  // namespace
 #endif
 
+bool InitializeICUDefaultLocation(const char* exec_path,
+                                  const char* icu_data_file) {
+#if !defined(V8_I18N_SUPPORT)
+  return true;
+#else
+#if ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE
+  if (icu_data_file) {
+    return InitializeICU(icu_data_file);
+  }
+  char* icu_data_file_default;
+  RelativePath(&icu_data_file_default, exec_path, "icudtl.dat");
+  bool result = InitializeICU(icu_data_file_default);
+  free(icu_data_file_default);
+  return result;
+#else
+  return InitializeICU(NULL);
+#endif
+#endif
+}
+
 bool InitializeICU(const char* icu_data_file) {
 #if !defined(V8_I18N_SUPPORT)
   return true;
 #else
 #if ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_SHARED
   // We expect to find the ICU data module alongside the current module.
   HMODULE module = LoadLibraryA(ICU_UTIL_DATA_SHARED_MODULE_NAME);
   if (!module) return false;
 
   FARPROC addr = GetProcAddress(module, ICU_UTIL_DATA_SYMBOL);
@@ skipping 30 matching lines @@
 
   UErrorCode err = U_ZERO_ERROR;
   udata_setCommonData(reinterpret_cast<void*>(g_icu_data_ptr), &err);
   return err == U_ZERO_ERROR;
 #endif
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8