1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "base/threading/thread_id_name_manager.h"
6 
7 #include <stdlib.h>
8 #include <string.h>
9 
10 #include "base/logging.h"
11 #include "base/memory/singleton.h"
12 #include "base/strings/string_util.h"
13 
14 namespace base {
15 namespace {
16 
17 static const char kDefaultName[] = "";
18 static std::string* g_default_name;
19 
20 }
21 
ThreadIdNameManager()22 ThreadIdNameManager::ThreadIdNameManager()
23     : main_process_name_(NULL),
24       main_process_id_(kInvalidThreadId) {
25   g_default_name = new std::string(kDefaultName);
26 
27   AutoLock locked(lock_);
28   name_to_interned_name_[kDefaultName] = g_default_name;
29 }
30 
~ThreadIdNameManager()31 ThreadIdNameManager::~ThreadIdNameManager() {
32 }
33 
GetInstance()34 ThreadIdNameManager* ThreadIdNameManager::GetInstance() {
35   return Singleton<ThreadIdNameManager,
36       LeakySingletonTraits<ThreadIdNameManager> >::get();
37 }
38 
GetDefaultInternedString()39 const char* ThreadIdNameManager::GetDefaultInternedString() {
40   return g_default_name->c_str();
41 }
42 
RegisterThread(PlatformThreadHandle::Handle handle,PlatformThreadId id)43 void ThreadIdNameManager::RegisterThread(PlatformThreadHandle::Handle handle,
44                                          PlatformThreadId id) {
45   AutoLock locked(lock_);
46   thread_id_to_handle_[id] = handle;
47   thread_handle_to_interned_name_[handle] =
48       name_to_interned_name_[kDefaultName];
49 }
50 
SetName(PlatformThreadId id,const std::string & name)51 void ThreadIdNameManager::SetName(PlatformThreadId id,
52                                   const std::string& name) {
53   AutoLock locked(lock_);
54   NameToInternedNameMap::iterator iter = name_to_interned_name_.find(name);
55   std::string* leaked_str = NULL;
56   if (iter != name_to_interned_name_.end()) {
57     leaked_str = iter->second;
58   } else {
59     leaked_str = new std::string(name);
60     name_to_interned_name_[name] = leaked_str;
61   }
62 
63   ThreadIdToHandleMap::iterator id_to_handle_iter =
64       thread_id_to_handle_.find(id);
65 
66   // The main thread of a process will not be created as a Thread object which
67   // means there is no PlatformThreadHandler registered.
68   if (id_to_handle_iter == thread_id_to_handle_.end()) {
69     main_process_name_ = leaked_str;
70     main_process_id_ = id;
71     return;
72   }
73   thread_handle_to_interned_name_[id_to_handle_iter->second] = leaked_str;
74 }
75 
GetName(PlatformThreadId id)76 const char* ThreadIdNameManager::GetName(PlatformThreadId id) {
77   AutoLock locked(lock_);
78 
79   if (id == main_process_id_)
80     return main_process_name_->c_str();
81 
82   ThreadIdToHandleMap::iterator id_to_handle_iter =
83       thread_id_to_handle_.find(id);
84   if (id_to_handle_iter == thread_id_to_handle_.end())
85     return name_to_interned_name_[kDefaultName]->c_str();
86 
87   ThreadHandleToInternedNameMap::iterator handle_to_name_iter =
88       thread_handle_to_interned_name_.find(id_to_handle_iter->second);
89   return handle_to_name_iter->second->c_str();
90 }
91 
RemoveName(PlatformThreadHandle::Handle handle,PlatformThreadId id)92 void ThreadIdNameManager::RemoveName(PlatformThreadHandle::Handle handle,
93                                      PlatformThreadId id) {
94   AutoLock locked(lock_);
95   ThreadHandleToInternedNameMap::iterator handle_to_name_iter =
96       thread_handle_to_interned_name_.find(handle);
97 
98   DCHECK(handle_to_name_iter != thread_handle_to_interned_name_.end());
99   thread_handle_to_interned_name_.erase(handle_to_name_iter);
100 
101   ThreadIdToHandleMap::iterator id_to_handle_iter =
102       thread_id_to_handle_.find(id);
103   DCHECK((id_to_handle_iter!= thread_id_to_handle_.end()));
104   // The given |id| may have been re-used by the system. Make sure the
105   // mapping points to the provided |handle| before removal.
106   if (id_to_handle_iter->second != handle)
107     return;
108 
109   thread_id_to_handle_.erase(id_to_handle_iter);
110 }
111 
112 }  // namespace base
113