share all the needed linux code with OpenBSD in chrome and content

chrome/common/multi_process_lock_linux.cc

 // Copyright (c) 2011 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 "chrome/common/multi_process_lock.h"
 
 #include <stdio.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <unistd.h>
 
 #include "base/eintr_wrapper.h"
 #include "base/logging.h"
 
 class MultiProcessLockLinux : public MultiProcessLock {
  public:
   explicit MultiProcessLockLinux(const std::string& name)
       : name_(name), fd_(-1) { }
 
   virtual ~MultiProcessLockLinux() {
     if (fd_ != -1) {
       Unlock();
     }
   }
 
   virtual bool TryLock() {
+    struct sockaddr_un address;
+
+    // +1 for terminator, +1 for 0 in position 0 that makes it an
+    // abstract named socket.
+    const size_t max_len = sizeof(address.sun_path) - 2;
+
     if (fd_ != -1) {
       DLOG(ERROR) << "MultiProcessLock is already locked - " << name_;
       return true;
     }
 
-    if (name_.length() > MULTI_PROCESS_LOCK_NAME_MAX_LEN) {
+    if (name_.length() > max_len) {
       LOG(ERROR) << "Socket name too long (" << name_.length()
-                 << " > " << MULTI_PROCESS_LOCK_NAME_MAX_LEN << ") - " << name_;
+                 << " > " << max_len << ") - " << name_;
       return false;
     }
 
-    struct sockaddr_un address;
-
-    // +1 for terminator, +1 for 0 in position 0 that makes it an
-    // abstract named socket.
-    // If this assert fails it is because sockaddr_un.sun_path size has been
-    // redefined and MULTI_PROCESS_LOCK_NAME_MAX_LEN can change accordingly.
-    COMPILE_ASSERT(sizeof(address.sun_path)
-        == MULTI_PROCESS_LOCK_NAME_MAX_LEN + 2, sun_path_size_changed);
-
     memset(&address, 0, sizeof(address));
     int print_length = snprintf(&address.sun_path[1],
-                                MULTI_PROCESS_LOCK_NAME_MAX_LEN + 1,
+                                max_len + 1,
                                 "%s", name_.c_str());
 
     if (print_length < 0 ||
-        print_length > static_cast<int>(MULTI_PROCESS_LOCK_NAME_MAX_LEN)) {
+        print_length > static_cast<int>(max_len)) {
       PLOG(ERROR) << "Couldn't create sun_path - " << name_;
       return false;
     }
 
     // Must set the first character of the path to something non-zero
     // before we call SUN_LEN which depends on strcpy working.
     address.sun_path[0] = '@';
     size_t length = SUN_LEN(&address);
 
     // Reset the first character of the path back to zero so that
@@ skipping 36 matching lines @@
 
  private:
   std::string name_;
   int fd_;
   DISALLOW_COPY_AND_ASSIGN(MultiProcessLockLinux);
 };
 
 MultiProcessLock* MultiProcessLock::Create(const std::string &name) {
   return new MultiProcessLockLinux(name);
 }