Revert of Remove all reference to carbon api

webrtc/base/iosfilesystem.mm

+/*
+ *  Copyright 2014 The WebRTC 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 in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// This file only exists because various iOS system APIs are only
+// available from Objective-C.  See unixfilesystem.cc for the only use
+// (enforced by a lack of a header file).
+
+#import <Foundation/NSPathUtilities.h>
+#import <Foundation/NSProcessInfo.h>
+#include <string.h>
+
+#include "webrtc/base/common.h"
+#include "webrtc/base/pathutils.h"
+
+// Return a new[]'d |char*| copy of the UTF8 representation of |s|.
+// Caller owns the returned memory and must use delete[] on it.
+static char* copyString(NSString* s) {
+  const char* utf8 = [s UTF8String];
+  size_t len = strlen(utf8) + 1;
+  char* copy = new char[len];
+  // This uses a new[] + strcpy (instead of strdup) because the
+  // receiver expects to be able to delete[] the returned pointer
+  // (instead of free()ing it).
+  strcpy(copy, utf8);
+  return copy;
+}
+
+// Return a (leaked) copy of a directory name suitable for application data.
+char* IOSDataDirectory() {
+  NSArray* paths = NSSearchPathForDirectoriesInDomains(
+      NSApplicationSupportDirectory, NSUserDomainMask, YES);
+  ASSERT([paths count] == 1);
+  return copyString([paths objectAtIndex:0]);
+}
+
+// Return a (leaked) copy of a directory name suitable for use as a $TEMP.
+char* IOSTempDirectory() {
+  return copyString(NSTemporaryDirectory());
+}
+
+// Return the binary's path.
+void IOSAppName(rtc::Pathname* path) {
+  NSProcessInfo *pInfo = [NSProcessInfo processInfo];
+  NSString* argv0 = [[pInfo arguments] objectAtIndex:0];
+  path->SetPathname([argv0 UTF8String]);
+}