| // Copyright (c) 2006-2008 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/path_service.h" |
| |
| #ifdef OS_WIN |
| #include <windows.h> |
| #include <shellapi.h> |
| #include <shlobj.h> |
| #endif |
| |
| #include "base/file_path.h" |
| #include "base/file_util.h" |
| #include "base/hash_tables.h" |
| #include "base/lock.h" |
| #include "base/logging.h" |
| #include "base/singleton.h" |
| |
| namespace base { |
| bool PathProvider(int key, FilePath* result); |
| #if defined(OS_WIN) |
| bool PathProviderWin(int key, FilePath* result); |
| #elif defined(OS_MACOSX) |
| bool PathProviderMac(int key, FilePath* result); |
| #elif defined(OS_POSIX) |
| bool PathProviderPosix(int key, FilePath* result); |
| #endif |
| } |
| |
| namespace { |
| |
| typedef base::hash_map<int, FilePath> PathMap; |
| |
| // We keep a linked list of providers. In a debug build we ensure that no two |
| // providers claim overlapping keys. |
| struct Provider { |
| PathService::ProviderFunc func; |
| struct Provider* next; |
| #ifndef NDEBUG |
| int key_start; |
| int key_end; |
| #endif |
| bool is_static; |
| }; |
| |
| static Provider base_provider = { |
| base::PathProvider, |
| NULL, |
| #ifndef NDEBUG |
| base::PATH_START, |
| base::PATH_END, |
| #endif |
| true |
| }; |
| |
| #if defined(OS_WIN) |
| static Provider base_provider_win = { |
| base::PathProviderWin, |
| &base_provider, |
| #ifndef NDEBUG |
| base::PATH_WIN_START, |
| base::PATH_WIN_END, |
| #endif |
| true |
| }; |
| #endif |
| |
| #if defined(OS_MACOSX) |
| static Provider base_provider_mac = { |
| base::PathProviderMac, |
| &base_provider, |
| #ifndef NDEBUG |
| base::PATH_MAC_START, |
| base::PATH_MAC_END, |
| #endif |
| true |
| }; |
| #endif |
| |
| #if defined(OS_POSIX) && !defined(OS_MACOSX) |
| static Provider base_provider_posix = { |
| base::PathProviderPosix, |
| &base_provider, |
| #ifndef NDEBUG |
| 0, |
| 0, |
| #endif |
| true |
| }; |
| #endif |
| |
| |
| struct PathData { |
| Lock lock; |
| PathMap cache; // Cache mappings from path key to path value. |
| PathMap overrides; // Track path overrides. |
| Provider* providers; // Linked list of path service providers. |
| |
| PathData() { |
| #if defined(OS_WIN) |
| providers = &base_provider_win; |
| #elif defined(OS_MACOSX) |
| providers = &base_provider_mac; |
| #elif defined(OS_POSIX) |
| providers = &base_provider_posix; |
| #endif |
| } |
| |
| ~PathData() { |
| Provider* p = providers; |
| while (p) { |
| Provider* next = p->next; |
| if (!p->is_static) |
| delete p; |
| p = next; |
| } |
| } |
| }; |
| |
| static PathData* GetPathData() { |
| return Singleton<PathData>::get(); |
| } |
| |
| } // namespace |
| |
| |
| // static |
| bool PathService::GetFromCache(int key, FilePath* result) { |
| PathData* path_data = GetPathData(); |
| AutoLock scoped_lock(path_data->lock); |
| |
| // check for a cached version |
| PathMap::const_iterator it = path_data->cache.find(key); |
| if (it != path_data->cache.end()) { |
| *result = it->second; |
| return true; |
| } |
| return false; |
| } |
| |
| // static |
| bool PathService::GetFromOverrides(int key, FilePath* result) { |
| PathData* path_data = GetPathData(); |
| AutoLock scoped_lock(path_data->lock); |
| |
| // check for an overriden version. |
| PathMap::const_iterator it = path_data->overrides.find(key); |
| if (it != path_data->overrides.end()) { |
| *result = it->second; |
| return true; |
| } |
| return false; |
| } |
| |
| // static |
| void PathService::AddToCache(int key, const FilePath& path) { |
| PathData* path_data = GetPathData(); |
| AutoLock scoped_lock(path_data->lock); |
| // Save the computed path in our cache. |
| path_data->cache[key] = path; |
| } |
| |
| // TODO(brettw): this function does not handle long paths (filename > MAX_PATH) |
| // characters). This isn't supported very well by Windows right now, so it is |
| // moot, but we should keep this in mind for the future. |
| // static |
| bool PathService::Get(int key, FilePath* result) { |
| PathData* path_data = GetPathData(); |
| DCHECK(path_data); |
| DCHECK(result); |
| DCHECK(key >= base::DIR_CURRENT); |
| |
| // special case the current directory because it can never be cached |
| if (key == base::DIR_CURRENT) |
| return file_util::GetCurrentDirectory(result); |
| |
| if (GetFromCache(key, result)) |
| return true; |
| |
| if (GetFromOverrides(key, result)) |
| return true; |
| |
| FilePath path; |
| |
| // search providers for the requested path |
| // NOTE: it should be safe to iterate here without the lock |
| // since RegisterProvider always prepends. |
| Provider* provider = path_data->providers; |
| while (provider) { |
| if (provider->func(key, &path)) |
| break; |
| DCHECK(path.empty()) << "provider should not have modified path"; |
| provider = provider->next; |
| } |
| |
| if (path.empty()) |
| return false; |
| |
| AddToCache(key, path); |
| |
| *result = path; |
| return true; |
| } |
| |
| #if defined(OS_WIN) |
| // static |
| bool PathService::Get(int key, std::wstring* result) { |
| // Deprecated compatibility function. |
| FilePath path; |
| if (!Get(key, &path)) |
| return false; |
| *result = path.ToWStringHack(); |
| return true; |
| } |
| #endif |
| |
| // TODO(evan): remove me -- see comments in header. |
| bool PathService::IsOverridden(int key) { |
| PathData* path_data = GetPathData(); |
| DCHECK(path_data); |
| AutoLock scoped_lock(path_data->lock); |
| return path_data->overrides.find(key) != path_data->overrides.end(); |
| } |
| |
| bool PathService::Override(int key, const FilePath& path) { |
| PathData* path_data = GetPathData(); |
| DCHECK(path_data); |
| DCHECK(key > base::DIR_CURRENT) << "invalid path key"; |
| |
| FilePath file_path = path; |
| |
| // Make sure the directory exists. We need to do this before we translate |
| // this to the absolute path because on POSIX, AbsolutePath fails if called |
| // on a non-existant path. |
| if (!file_util::PathExists(file_path) && |
| !file_util::CreateDirectory(file_path)) |
| return false; |
| |
| // We need to have an absolute path, as extensions and plugins don't like |
| // relative paths, and will glady crash the browser in CHECK()s if they get a |
| // relative path. |
| if (!file_util::AbsolutePath(&file_path)) |
| return false; |
| |
| AutoLock scoped_lock(path_data->lock); |
| |
| // Clear the cache now. Some of its entries could have depended |
| // on the value we are overriding, and are now out of sync with reality. |
| path_data->cache.clear(); |
| |
| path_data->cache[key] = file_path; |
| path_data->overrides[key] = file_path; |
| |
| return true; |
| } |
| |
| void PathService::RegisterProvider(ProviderFunc func, int key_start, |
| int key_end) { |
| PathData* path_data = GetPathData(); |
| DCHECK(path_data); |
| DCHECK(key_end > key_start); |
| |
| AutoLock scoped_lock(path_data->lock); |
| |
| Provider* p; |
| |
| #ifndef NDEBUG |
| p = path_data->providers; |
| while (p) { |
| DCHECK(key_start >= p->key_end || key_end <= p->key_start) << |
| "path provider collision"; |
| p = p->next; |
| } |
| #endif |
| |
| p = new Provider; |
| p->is_static = false; |
| p->func = func; |
| p->next = path_data->providers; |
| #ifndef NDEBUG |
| p->key_start = key_start; |
| p->key_end = key_end; |
| #endif |
| path_data->providers = p; |
| } |