Move EnvironmentVariableGetter from base/linux_util.h to base/env_var.h. Labe...

base/env_var.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.
+
+#include "base/env_var.h"
+
+#if defined(OS_POSIX)
+#include <stdlib.h>
+#elif defined(OS_WIN)
+#include <windows.h>
+#endif
+
+#include "base/string_util.h"
+
+#if defined(OS_WIN)
+#include "base/scoped_ptr.h"
+#include "base/utf_string_conversions.h"
+#endif
+
+namespace {
+
+class EnvVarGetterImpl
+    : public base::EnvVarGetter {
+ public:
+  virtual bool GetEnv(const char* variable_name, std::string* result) {
+    if (GetEnvImpl(variable_name, result))
+      return true;
+
+    // Some commonly used variable names are uppercase while others
+    // are lowercase, which is inconsistent. Let's try to be helpful
+    // and look for a variable name with the reverse case.
+    // I.e. HTTP_PROXY may be http_proxy for some users/systems.
+    char first_char = variable_name[0];
+    std::string alternate_case_var;
+    if (first_char >= 'a' && first_char <= 'z')
+      alternate_case_var = StringToUpperASCII(std::string(variable_name));
+    else if (first_char >= 'A' && first_char <= 'Z')
+      alternate_case_var = StringToLowerASCII(std::string(variable_name));
+    else
+      return false;
+    return GetEnvImpl(alternate_case_var.c_str(), result);
+  }
+ private:
+  bool GetEnvImpl(const char* variable_name, std::string* result) {
+#if defined(OS_POSIX)
+    const char* env_value = getenv(variable_name);
+    if (!env_value)
+      return false;
+    // Note that the variable may be defined but empty.
+    if (result)
+      *result = env_value;
+    return true;
+#elif defined(OS_WIN)
+    DWORD value_length = ::GetEnvironmentVariable(
+        UTF8ToWide(variable_name).c_str(), NULL, 0);
+    if (value_length == 0)
+      return false;
+    if (result) {
+      scoped_array<wchar_t> value(new wchar_t[value_length]);
+      ::GetEnvironmentVariable(UTF8ToWide(variable_name).c_str(), value.get(),
+                               value_length);
+      *result = WideToUTF8(value.get());
+    }
+    return true;
+#else
+#error need to port
+#endif
+  }
+};
+
+}  // namespace
+
+namespace base {
+
+// static
+EnvVarGetter* EnvVarGetter::Create() {
+  return new EnvVarGetterImpl();
+}
+
+}  // namespace base