Adding GetOutputDir method to test_support library.

The unittest is not ideal for this, but I would have to use similar code as the implementation of the GetOutputDir in order to verify that it actually runs, so it wouldn't make much sense with a test like that.

It compiles and runs on Linux, Win and Mac. The folder gets created and is writeable from other tests.

I have tried using the GetOutputDir from another project that writes output files and it works as intended on all platforms.

Review URL: http://webrtc-codereview.appspot.com/270001

git-svn-id: http://webrtc.googlecode.com/svn/trunk@906 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/test/testsupport/fileutils.cc b/test/testsupport/fileutils.cc
index 098dad7..9b54989 100644
--- a/test/testsupport/fileutils.cc
+++ b/test/testsupport/fileutils.cc
@@ -13,11 +13,14 @@
 #ifdef WIN32
 #include <direct.h>
 #define GET_CURRENT_DIR _getcwd
-#define PATH_DELIMITER "\\"
 #else
 #include <unistd.h>
 #define GET_CURRENT_DIR getcwd
-#define PATH_DELIMITER "/"
+#endif
+
+#include <sys/stat.h>  // To check for directory existence.
+#ifndef S_ISDIR  // Not defined in stat.h on Windows.
+#define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
 #endif
 
 #include <cstdio>
@@ -25,8 +28,14 @@
 namespace webrtc {
 namespace test {
 
+#ifdef WIN32
+static const char* kPathDelimiter = "\\";
+#else
+static const char* kPathDelimiter = "/";
+#endif
 // The file we're looking for to identify the project root dir.
 static const char* kProjectRootFileName = "DEPS";
+static const char* kOutputDirName = "out";
 const char* kCannotFindProjectRootDir = "ERROR_CANNOT_FIND_PROJECT_ROOT_DIR";
 
 std::string GetProjectRootPath() {
@@ -39,18 +48,18 @@
   // Check for our file that verifies the root dir.
   std::string current_path(path_buffer);
   FILE* file = NULL;
-  int path_delimiter_index = current_path.find_last_of(PATH_DELIMITER);
+  int path_delimiter_index = current_path.find_last_of(kPathDelimiter);
   while (path_delimiter_index > -1) {
-    std::string root_filename = current_path + PATH_DELIMITER +
+    std::string root_filename = current_path + kPathDelimiter +
         kProjectRootFileName;
     file = fopen(root_filename.c_str(), "r");
     if (file != NULL) {
-      return current_path + PATH_DELIMITER;
+      return current_path + kPathDelimiter;
     }
 
     // Move up one directory in the directory tree.
     current_path = current_path.substr(0, path_delimiter_index);
-    path_delimiter_index = current_path.find_last_of(PATH_DELIMITER);
+    path_delimiter_index = current_path.find_last_of(kPathDelimiter);
   }
 
   // Reached the root directory.
@@ -58,5 +67,28 @@
   return kCannotFindProjectRootDir;
 }
 
-}  // namespace webrtc
+std::string GetOutputDir() {
+  std::string path = GetProjectRootPath();
+  if (path == kCannotFindProjectRootDir) {
+    return kCannotFindProjectRootDir;
+  }
+  path += kOutputDirName;
+  struct stat path_info = {0};
+  // Check if the path exists already:
+  if (stat(path.c_str(), &path_info) == 0) {
+    if (!S_ISDIR(path_info.st_mode)) {
+      fprintf(stderr, "Path %s exists but is not a directory! Remove this file "
+              "and re-run to create the output folder.\n", path.c_str());
+      return kCannotFindProjectRootDir;
+    }
+  } else {
+#ifdef WIN32
+      _mkdir(path.c_str());
+#else
+      mkdir(path.c_str(),  S_IRWXU | S_IRWXG | S_IRWXO);
+#endif
+  }
+  return path + kPathDelimiter;
+}
 }  // namespace test
+}  // namespace webrtc
diff --git a/test/testsupport/fileutils.h b/test/testsupport/fileutils.h
index becf56a..0dd662a 100644
--- a/test/testsupport/fileutils.h
+++ b/test/testsupport/fileutils.h
@@ -88,6 +88,19 @@
 // kCannotFindProjectRootDir is returned.
 std::string GetProjectRootPath();
 
+// Creates and returns the absolute path to the output directory where log files
+// and other test artifacts should be put. The output directory is always a
+// directory named "out" at the top-level of the project, i.e. a subfolder to
+// the path returned by GetProjectRootPath().
+//
+// Details described for GetProjectRootPath() apply here too.
+//
+// Returns the absolute path to the output directory (named "out") below the
+// project root dir WITH a trailing path delimiter.
+// If the project root is not found, the string specified by
+// kCannotFindProjectRootDir is returned.
+std::string GetOutputDir();
+
 }  // namespace test
 }  // namespace webrtc
 
diff --git a/test/testsupport/fileutils_unittest.cc b/test/testsupport/fileutils_unittest.cc
index f3772c4..1f8a7ac 100644
--- a/test/testsupport/fileutils_unittest.cc
+++ b/test/testsupport/fileutils_unittest.cc
@@ -7,53 +7,103 @@
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
+
+#include <cstdio>
 #include "fileutils.h"
 #include "gtest/gtest.h"
 
 #ifdef WIN32
-#define PATH_DELIMITER "\\"
+#include <direct.h>
+#define GET_CURRENT_DIR _getcwd
+static const char* kPathDelimiter = "\\";
 #else
-#define PATH_DELIMITER "/"
+#include <unistd.h>
+#define GET_CURRENT_DIR getcwd
+static const char* kPathDelimiter = "/";
 #endif
 
 namespace webrtc {
 namespace test {
 
-// Tests that the project root path is returnd for the default working directory
-// that is automatically set when the test executable is launched.
+// Test fixture to restore the working directory between each test, since some
+// of them change it with chdir during execution (not restored by the
+// gtest framework).
+class FileUtilsTest: public testing::Test {
+ protected:
+  FileUtilsTest() {
+    original_working_dir_ = GetWorkingDir();
+  }
+  virtual ~FileUtilsTest() {}
+  void SetUp() {
+    chdir(original_working_dir_.c_str());
+  }
+  void TearDown() {}
+ private:
+  std::string original_working_dir_;
+  static std::string GetWorkingDir() {
+    char path_buffer[FILENAME_MAX];
+    EXPECT_TRUE(GET_CURRENT_DIR(path_buffer, sizeof(path_buffer)))
+      << "Cannot get current working directory!";
+    return std::string(path_buffer);
+  }
+};
+
+// Tests that the project root path is returned for the default working
+// directory that is automatically set when the test executable is launched.
 // The test is not fully testing the implementation, since we cannot be sure
 // of where the executable was launched from.
 // The test will fail if the top level directory is not named "trunk".
-TEST(FileUtilsTest, GetProjectRootPathFromUnchangedWorkingDir) {
+TEST_F(FileUtilsTest, GetProjectRootPathFromUnchangedWorkingDir) {
   std::string path = GetProjectRootPath();
   std::string expected_end = "trunk";
-  expected_end = PATH_DELIMITER + expected_end + PATH_DELIMITER;
+  expected_end = kPathDelimiter + expected_end + kPathDelimiter;
+  ASSERT_EQ(path.length() - expected_end.length(), path.find(expected_end));
+}
+
+// Similar to the above test, but for the output dir
+TEST_F(FileUtilsTest, GetOutputDirFromUnchangedWorkingDir) {
+  std::string path = GetOutputDir();
+  std::string expected_end = "out";
+  expected_end = kPathDelimiter + expected_end + kPathDelimiter;
   ASSERT_EQ(path.length() - expected_end.length(), path.find(expected_end));
 }
 
 // Tests setting the current working directory to a directory three levels
 // deeper from the current one. Then testing that the project path returned
 // is still the same, when the function under test is called again.
-TEST(FileUtilsTest, GetProjectRootPathFromDeeperWorkingDir) {
+TEST_F(FileUtilsTest, GetProjectRootPathFromDeeperWorkingDir) {
   std::string path = GetProjectRootPath();
   std::string original_working_dir = path;  // This is the correct project root
-
   // Change to a subdirectory path (the full path doesn't have to exist).
   path += "foo/bar/baz";
   chdir(path.c_str());
-
   ASSERT_EQ(original_working_dir, GetProjectRootPath());
 }
 
+// Similar to the above test, but for the output dir
+TEST_F(FileUtilsTest, GetOutputDirFromDeeperWorkingDir) {
+  std::string path = GetOutputDir();
+  std::string original_working_dir = path;
+  path += "foo/bar/baz";
+  chdir(path.c_str());
+  ASSERT_EQ(original_working_dir, GetOutputDir());
+}
+
 // Tests with current working directory set to a directory higher up in the
 // directory tree than the project root dir. This case shall return a specified
 // error string as a directory (which will be an invalid path).
-TEST(FileUtilsTest, GetProjectRootPathFromRootWorkingDir) {
+TEST_F(FileUtilsTest, GetProjectRootPathFromRootWorkingDir) {
   // Change current working dir to the root of the current file system
   // (this will always be "above" our project root dir).
-  chdir(PATH_DELIMITER);
+  chdir(kPathDelimiter);
   ASSERT_EQ(kCannotFindProjectRootDir, GetProjectRootPath());
 }
 
+// Similar to the above test, but for the output dir
+TEST_F(FileUtilsTest, GetOutputDirFromRootWorkingDir) {
+  chdir(kPathDelimiter);
+  ASSERT_EQ(kCannotFindProjectRootDir, GetOutputDir());
+}
+
 }  // namespace test
 }  // namespace webrtc