base: Add UnSetEnv function to EnvVarGetter API.

chrome/plugin/plugin_main_mac.mm

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// 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/chrome_application_mac.h"
+#include "base/env_var.h"
+#include "base/scoped_ptr.h"
 #include "base/string_util.h"
 #include "chrome/common/plugin_carbon_interpose_constants_mac.h"
 #include "chrome/plugin/plugin_interpose_util_mac.h"
 
 #if !defined(__LP64__)
 void TrimInterposeEnvironment() {
-  const char* interpose_list =
-      getenv(plugin_interpose_strings::kDYLDInsertLibrariesKey);
-  if (!interpose_list) {
+  scoped_ptr<base::EnvVarGetter> env(base::EnvVarGetter::Create());
+
+  std::string interpose_list;
+  if (!env->GetEnv(plugin_interpose_strings::kDYLDInsertLibrariesKey,
+                   &interpose_list)) {
     NOTREACHED() << "No interposing libraries set";
     return;
   }
 
   // The list is a :-separated list of paths. Because we append our interpose
   // library just before forking in plugin_process_host.cc, the only cases we
   // need to handle are:
   // 1) The whole string is "<kInterposeLibraryPath>", so just clear it, or
   // 2) ":<kInterposeLibraryPath>" is the end of the string, so trim and re-set.
-  int suffix_offset = strlen(interpose_list) -
+  int suffix_offset = strlen(interpose_list.c_str()) -

[viettrungluu, 2010/07/31 01:50:02]

No, don't do strlen(foo.c_str()). std::string has a method for that.

       strlen(plugin_interpose_strings::kInterposeLibraryPath);
+
   if (suffix_offset == 0 &&
-      strcmp(interpose_list,
+      strcmp(interpose_list.c_str(),
              plugin_interpose_strings::kInterposeLibraryPath) == 0) {
-    unsetenv(plugin_interpose_strings::kDYLDInsertLibrariesKey);
+    env->UnSetEnv(plugin_interpose_strings::kDYLDInsertLibrariesKey);
   } else if (suffix_offset > 0 && interpose_list[suffix_offset - 1] == ':' &&
-             strcmp(interpose_list + suffix_offset,
+             strcmp(interpose_list.c_str() + suffix_offset,

[viettrungluu, 2010/07/31 01:50:02]

You shouldn't do foo.c_str() + n either. There's also a better way to do that.

                     plugin_interpose_strings::kInterposeLibraryPath) == 0) {
-    std::string trimmed_list =
-        std::string(interpose_list).substr(0, suffix_offset - 1);
-    setenv(plugin_interpose_strings::kDYLDInsertLibrariesKey,
-           trimmed_list.c_str(), 1);
+    std::string trimmed_list = interpose_list.substr(0, suffix_offset - 1);
+    env->SetEnv(plugin_interpose_strings::kDYLDInsertLibrariesKey,
+                trimmed_list.c_str());
   } else {
     NOTREACHED() << "Missing Carbon interposing library";
   }
 }
 #endif
 
 void InitializeChromeApplication() {
   [CrApplication sharedApplication];
 
   mac_plugin_interposing::SetUpCocoaInterposing();
 }