base_paths_linux.cc revision 78494470aa829a52d6709093dd00e7704053e806 
1// Copyright (c) 2010 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/base_paths.h"
6
7#include <unistd.h>
8#if defined(OS_FREEBSD)
9#include <sys/param.h>
10#include <sys/sysctl.h>
11#endif
12
13#include "base/environment.h"
14#include "base/file_path.h"
15#include "base/file_util.h"
16#include "base/logging.h"
17#include "base/path_service.h"
18#include "base/scoped_ptr.h"
19#include "base/sys_string_conversions.h"
20#include "base/nix/xdg_util.h"
21
22namespace base {
23
24#if defined(OS_LINUX)
25const char kSelfExe[] = "/proc/self/exe";
26#elif defined(OS_SOLARIS)
27const char kSelfExe[] = getexecname();
28#endif
29
30// The name of this file relative to the source root. This is used for checking
31// that the source checkout is in the correct place.
32static const char kThisSourceFile[] = "base/base_paths_linux.cc";
33
34bool PathProviderPosix(int key, FilePath* result) {
35  FilePath path;
36  switch (key) {
37    case base::FILE_EXE:
38    case base::FILE_MODULE: {  // TODO(evanm): is this correct?
39#if defined(OS_LINUX)
40      char bin_dir[PATH_MAX + 1];
41      int bin_dir_size = readlink(kSelfExe, bin_dir, PATH_MAX);
42      if (bin_dir_size < 0 || bin_dir_size > PATH_MAX) {
43        NOTREACHED() << "Unable to resolve " << kSelfExe << ".";
44        return false;
45      }
46      bin_dir[bin_dir_size] = 0;
47      *result = FilePath(bin_dir);
48      return true;
49#elif defined(OS_FREEBSD)
50      int name[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
51      char bin_dir[PATH_MAX + 1];
52      size_t length = sizeof(bin_dir);
53      int error = sysctl(name, 4, bin_dir, &length, NULL, 0);
54      if (error < 0 || length == 0 || strlen(bin_dir) == 0) {
55        NOTREACHED() << "Unable to resolve path.";
56        return false;
57      }
58      bin_dir[strlen(bin_dir)] = 0;
59      *result = FilePath(bin_dir);
60      return true;
61#endif
62    }
63    case base::DIR_SOURCE_ROOT: {
64      // Allow passing this in the environment, for more flexibility in build
65      // tree configurations (sub-project builds, gyp --output_dir, etc.)
66      scoped_ptr<base::Environment> env(base::Environment::Create());
67      std::string cr_source_root;
68      if (env->GetVar("CR_SOURCE_ROOT", &cr_source_root)) {
69        path = FilePath(cr_source_root);
70        if (file_util::PathExists(path.Append(kThisSourceFile))) {
71          *result = path;
72          return true;
73        } else {
74          LOG(WARNING) << "CR_SOURCE_ROOT is set, but it appears to not "
75                       << "point to the correct source root directory.";
76        }
77      }
78      // On POSIX, unit tests execute two levels deep from the source root.
79      // For example:  sconsbuild/{Debug|Release}/net_unittest
80      if (PathService::Get(base::DIR_EXE, &path)) {
81        path = path.DirName().DirName();
82        if (file_util::PathExists(path.Append(kThisSourceFile))) {
83          *result = path;
84          return true;
85        }
86      }
87      // In a case of WebKit-only checkout, executable files are put into
88      // WebKit/out/{Debug|Release}, and we should return WebKit/WebKit/chromium
89      // for DIR_SOURCE_ROOT.
90      if (PathService::Get(base::DIR_EXE, &path)) {
91        path = path.DirName().DirName().Append("WebKit/chromium");
92        if (file_util::PathExists(path.Append(kThisSourceFile))) {
93          *result = path;
94          return true;
95        }
96      }
97      // If that failed (maybe the build output is symlinked to a different
98      // drive) try assuming the current directory is the source root.
99      if (file_util::GetCurrentDirectory(&path) &&
100          file_util::PathExists(path.Append(kThisSourceFile))) {
101        *result = path;
102        return true;
103      }
104      LOG(ERROR) << "Couldn't find your source root.  "
105                 << "Try running from your chromium/src directory.";
106      return false;
107    }
108    case base::DIR_CACHE:
109#ifdef ANDROID
110      NOTREACHED();
111      return false;
112#else
113      scoped_ptr<base::Environment> env(base::Environment::Create());
114      FilePath cache_dir(base::nix::GetXDGDirectory(env.get(), "XDG_CACHE_HOME",
115                                                    ".cache"));
116      *result = cache_dir;
117      return true;
118#endif
119  }
120  return false;
121}
122
123}  // namespace base
124