posix: refactor duplicated path-handling code

We had the same code in three headers, and an "if FREEBSD" in a
_linux.cc file.

Review URL: http://codereview.chromium.org/414063

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@32722 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 63 insertions, 0 deletions

diff --git a/base/base_paths_posix.cc b/base/base_paths_posix.cc
new file mode 100644
index 0000000..799c135
--- /dev/null
+++ b/base/base_paths_posix.cc
@@ -0,0 +1,63 @@
+// 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/base_paths.h"
+
+#include <unistd.h>
+
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/path_service.h"
+#include "base/string_piece.h"
+#include "base/sys_string_conversions.h"
+
+namespace base {
+
+#if defined(OS_LINUX)
+const char kSelfExe[] = "/proc/self/exe";
+#elif defined(OS_FREEBSD)
+const char kSelfExe[] = "/proc/curproc/file";
+#endif
+
+bool PathProviderPosix(int key, FilePath* result) {
+  FilePath path;
+  switch (key) {
+    case base::FILE_EXE:
+    case base::FILE_MODULE: {  // TODO(evanm): is this correct?
+      char bin_dir[PATH_MAX + 1];
+      int bin_dir_size = readlink(kSelfExe, bin_dir, PATH_MAX);
+      if (bin_dir_size < 0 || bin_dir_size > PATH_MAX) {
+        NOTREACHED() << "Unable to resolve " << kSelfExe << ".";
+        return false;
+      }
+      bin_dir[bin_dir_size] = 0;
+      *result = FilePath(bin_dir);
+      return true;
+    }
+    case base::DIR_SOURCE_ROOT:
+      // On POSIX, unit tests execute two levels deep from the source root.
+      // For example:  sconsbuild/{Debug|Release}/net_unittest
+      if (PathService::Get(base::DIR_EXE, &path)) {
+        path = path.DirName().DirName();
+        if (file_util::PathExists(path.Append("base/base_paths_posix.cc"))) {
+          *result = path;
+          return true;
+        }
+      }
+      // If that failed (maybe the build output is symlinked to a different
+      // drive) try assuming the current directory is the source root.
+      if (file_util::GetCurrentDirectory(&path) &&
+          file_util::PathExists(path.Append("base/base_paths_posix.cc"))) {
+        *result = path;
+        return true;
+      }
+      LOG(ERROR) << "Couldn't find your source root.  "
+                 << "Try running from your chromium/src directory.";
+      return false;
+  }
+  return false;
+}
+
+}  // namespace base