GN: aix port along with linux_s390x, linux_ppc64 and linux_ppc64le support.

base/memory/shared_memory_posix.cc

 // Copyright (c) 2012 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/memory/shared_memory.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <stddef.h>
 #include <sys/mman.h>
@@ skipping 139 matching lines @@
     int fd = HANDLE_EINTR(
         open(path.value().c_str(), O_RDWR | O_CREAT | O_EXCL, kOwnerOnly));
     if (fd == -1 && options.open_existing_deprecated) {
       // If this doesn't work, try and open an existing file in append mode.
       // Opening an existing file in a world writable directory has two main
       // security implications:
       // - Attackers could plant a file under their control, so ownership of
       //   the file is checked below.
       // - Attackers could plant a symbolic link so that an unexpected file
       //   is opened, so O_NOFOLLOW is passed to open().
+#if !defined(OS_AIX)
       fd = HANDLE_EINTR(
           open(path.value().c_str(), O_RDWR | O_APPEND | O_NOFOLLOW));
-
+#else
+      // AIX has no 64-bit support for open falgs such as -
+      //  O_CLOEXEC, O_NOFOLLOW and O_TTY_INIT.
+      fd = HANDLE_EINTR(open(path.value().c_str(), O_RDWR | O_APPEND));
+#endif
       // Check that the current user owns the file.
       // If uid != euid, then a more complex permission model is used and this
       // API is not appropriate.
       const uid_t real_uid = getuid();
       const uid_t effective_uid = geteuid();
       struct stat sb;
       if (fd >= 0 &&
           (fstat(fd, &sb) != 0 || sb.st_uid != real_uid ||
            sb.st_uid != effective_uid)) {
         LOG(ERROR) <<
@@ skipping 234 matching lines @@
   base::ThreadRestrictions::ScopedAllowIO allow_io;
   struct stat file_stat;
   if (HANDLE_EINTR(::fstat(static_cast<int>(handle().fd), &file_stat)) != 0)
     return false;
   id->first = file_stat.st_dev;
   id->second = file_stat.st_ino;
   return true;
 }
 
 }  // namespace base