base: Rename EnvVarGetter to Environment.

Now EnvVarGetter do much more than getting environment variables.

Per suggestion from Pawel in http://codereview.chromium.org/3043018/.

BUG=None
TEST=trybots

Signed-off-by: Thiago Farina <tfarina@chromium.org>

Review URL: http://codereview.chromium.org/3052034

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@54696 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 126 insertions, 0 deletions

diff --git a/base/environment.cc b/base/environment.cc
new file mode 100644
index 0000000..2ebdd43
--- /dev/null
+++ b/base/environment.cc
@@ -0,0 +1,126 @@
+// 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/environment.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 EnvironmentImpl : public base::Environment {
+ 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);
+  }
+
+  virtual bool SetEnv(const char* variable_name, const std::string& new_value) {
+    return SetEnvImpl(variable_name, new_value);
+  }
+
+  virtual bool UnSetEnv(const char* variable_name) {
+    return UnSetEnvImpl(variable_name);
+  }
+
+ 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
+  }
+
+  bool SetEnvImpl(const char* variable_name, const std::string& new_value) {
+#if defined(OS_POSIX)
+    // On success, zero is returned.
+    return setenv(variable_name, new_value.c_str(), 1) == 0;
+#elif defined(OS_WIN)
+    // On success, a nonzero is returned.
+    return ::SetEnvironmentVariable(ASCIIToWide(variable_name).c_str(),
+                                    ASCIIToWide(new_value).c_str()) != 0;
+#endif
+  }
+
+  bool UnSetEnvImpl(const char* variable_name) {
+#if defined(OS_POSIX)
+    // On success, zero is returned.
+    return unsetenv(variable_name) == 0;
+#elif defined(OS_WIN)
+    // On success, a nonzero is returned.
+    return ::SetEnvironmentVariable(ASCIIToWide(variable_name).c_str(),
+                                    NULL) != 0;
+#endif
+  }
+};
+
+}  // namespace
+
+namespace base {
+
+namespace env_vars {
+
+#if defined(OS_POSIX)
+// On Posix systems, this variable contains the location of the user's home
+// directory. (e.g, /home/username/).
+const char kHome[] = "HOME";
+#endif
+
+}  // namespace env_vars
+
+Environment::~Environment() {}
+
+// static
+Environment* Environment::Create() {
+  return new EnvironmentImpl();
+}
+
+bool Environment::HasEnv(const char* variable_name) {
+  return GetEnv(variable_name, NULL);
+}
+
+}  // namespace base