Move some more file utils to the base namespace.

This also swaps the order of the parameters to GetShmemTempDir so the out
parameter is last, and enhances some documentation.

Review URL: https://codereview.chromium.org/93263002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238144 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 110 insertions, 109 deletions

diff --git a/base/file_util_posix.cc b/base/file_util_posix.cc
index 027337f..b6a4945 100644
--- a/base/file_util_posix.cc
+++ b/base/file_util_posix.cc
@@ -150,6 +150,47 @@ std::string TempFileName() {
 #endif
 }
 
+// Creates and opens a temporary file in |directory|, returning the
+// file descriptor. |path| is set to the temporary file path.
+// This function does NOT unlink() the file.
+int CreateAndOpenFdForTemporaryFile(FilePath directory, FilePath* path) {
+  ThreadRestrictions::AssertIOAllowed();  // For call to mkstemp().
+  *path = directory.Append(base::TempFileName());
+  const std::string& tmpdir_string = path->value();
+  // this should be OK since mkstemp just replaces characters in place
+  char* buffer = const_cast<char*>(tmpdir_string.c_str());
+
+  return HANDLE_EINTR(mkstemp(buffer));
+}
+
+#if defined(OS_LINUX)
+// Determine if /dev/shm files can be mapped and then mprotect'd PROT_EXEC.
+// This depends on the mount options used for /dev/shm, which vary among
+// different Linux distributions and possibly local configuration.  It also
+// depends on details of kernel--ChromeOS uses the noexec option for /dev/shm
+// but its kernel allows mprotect with PROT_EXEC anyway.
+bool DetermineDevShmExecutable() {
+  bool result = false;
+  FilePath path;
+  int fd = CreateAndOpenFdForTemporaryFile(FilePath("/dev/shm"), &path);
+  if (fd >= 0) {
+    file_util::ScopedFD shm_fd_closer(&fd);
+    DeleteFile(path, false);
+    long sysconf_result = sysconf(_SC_PAGESIZE);
+    CHECK_GE(sysconf_result, 0);
+    size_t pagesize = static_cast<size_t>(sysconf_result);
+    CHECK_GE(sizeof(pagesize), sizeof(sysconf_result));
+    void *mapping = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0);
+    if (mapping != MAP_FAILED) {
+      if (mprotect(mapping, pagesize, PROT_READ | PROT_EXEC) == 0)
+        result = true;
+      munmap(mapping, pagesize);
+    }
+  }
+  return result;
+}
+#endif  // defined(OS_LINUX)
+
 }  // namespace
 
 FilePath MakeAbsoluteFilePath(const FilePath& input) {
@@ -405,6 +446,73 @@ bool SetPosixFilePermissions(const FilePath& path,
   return true;
 }
 
+#if !defined(OS_MACOSX)
+// This is implemented in file_util_mac.mm for Mac.
+bool GetTempDir(FilePath* path) {
+  const char* tmp = getenv("TMPDIR");
+  if (tmp) {
+    *path = FilePath(tmp);
+  } else {
+#if defined(OS_ANDROID)
+    return PathService::Get(base::DIR_CACHE, path);
+#else
+    *path = FilePath("/tmp");
+#endif
+  }
+  return true;
+}
+#endif  // !defined(OS_MACOSX)
+
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
+// This is implemented in file_util_mac.mm and file_util_android.cc for those
+// platforms.
+bool GetShmemTempDir(bool executable, FilePath* path) {
+#if defined(OS_LINUX)
+  bool use_dev_shm = true;
+  if (executable) {
+    static const bool s_dev_shm_executable = DetermineDevShmExecutable();
+    use_dev_shm = s_dev_shm_executable;
+  }
+  if (use_dev_shm) {
+    *path = FilePath("/dev/shm");
+    return true;
+  }
+#endif
+  return GetTempDir(path);
+}
+#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
+
+#if !defined(OS_MACOSX)
+FilePath GetHomeDir() {
+#if defined(OS_CHROMEOS)
+  if (SysInfo::IsRunningOnChromeOS())
+    return FilePath("/home/chronos/user");
+#endif
+
+  const char* home_dir = getenv("HOME");
+  if (home_dir && home_dir[0])
+    return FilePath(home_dir);
+
+#if defined(OS_ANDROID)
+  DLOG(WARNING) << "OS_ANDROID: Home directory lookup not yet implemented.";
+#elif defined(USE_GLIB) && !defined(OS_CHROMEOS)
+  // g_get_home_dir calls getpwent, which can fall through to LDAP calls.
+  ThreadRestrictions::AssertIOAllowed();
+
+  home_dir = g_get_home_dir();
+  if (home_dir && home_dir[0])
+    return FilePath(home_dir);
+#endif
+
+  FilePath rv;
+  if (GetTempDir(&rv))
+    return rv;
+
+  // Last resort.
+  return FilePath("/tmp");
+}
+#endif  // !defined(OS_MACOSX)
+
 }  // namespace base
 
 // -----------------------------------------------------------------------------
@@ -414,6 +522,7 @@ namespace file_util {
 using base::stat_wrapper_t;
 using base::CallStat;
 using base::CallLstat;
+using base::CreateAndOpenFdForTemporaryFile;
 using base::DirectoryExists;
 using base::FileEnumerator;
 using base::FilePath;
@@ -421,19 +530,6 @@ using base::MakeAbsoluteFilePath;
 using base::RealPath;
 using base::VerifySpecificPathControlledByUser;
 
-// Creates and opens a temporary file in |directory|, returning the
-// file descriptor. |path| is set to the temporary file path.
-// This function does NOT unlink() the file.
-int CreateAndOpenFdForTemporaryFile(FilePath directory, FilePath* path) {
-  base::ThreadRestrictions::AssertIOAllowed();  // For call to mkstemp().
-  *path = directory.Append(base::TempFileName());
-  const std::string& tmpdir_string = path->value();
-  // this should be OK since mkstemp just replaces characters in place
-  char* buffer = const_cast<char*>(tmpdir_string.c_str());
-
-  return HANDLE_EINTR(mkstemp(buffer));
-}
-
 bool CreateTemporaryFile(FilePath* path) {
   base::ThreadRestrictions::AssertIOAllowed();  // For call to close().
   FilePath directory;
@@ -448,7 +544,7 @@ bool CreateTemporaryFile(FilePath* path) {
 
 FILE* CreateAndOpenTemporaryShmemFile(FilePath* path, bool executable) {
   FilePath directory;
-  if (!GetShmemTempDir(&directory, executable))
+  if (!GetShmemTempDir(executable, &directory))
     return NULL;
 
   return CreateAndOpenTemporaryFileInDir(directory, path);
@@ -725,101 +821,6 @@ bool NormalizeFilePath(const FilePath& path, FilePath* normalized_path) {
   return true;
 }
 
-#if !defined(OS_MACOSX)
-bool GetTempDir(FilePath* path) {
-  const char* tmp = getenv("TMPDIR");
-  if (tmp)
-    *path = FilePath(tmp);
-  else
-#if defined(OS_ANDROID)
-    return PathService::Get(base::DIR_CACHE, path);
-#else
-    *path = FilePath("/tmp");
-#endif
-  return true;
-}
-
-#if !defined(OS_ANDROID)
-
-#if defined(OS_LINUX)
-// Determine if /dev/shm files can be mapped and then mprotect'd PROT_EXEC.
-// This depends on the mount options used for /dev/shm, which vary among
-// different Linux distributions and possibly local configuration.  It also
-// depends on details of kernel--ChromeOS uses the noexec option for /dev/shm
-// but its kernel allows mprotect with PROT_EXEC anyway.
-
-namespace {
-
-bool DetermineDevShmExecutable() {
-  bool result = false;
-  FilePath path;
-  int fd = CreateAndOpenFdForTemporaryFile(FilePath("/dev/shm"), &path);
-  if (fd >= 0) {
-    ScopedFD shm_fd_closer(&fd);
-    DeleteFile(path, false);
-    long sysconf_result = sysconf(_SC_PAGESIZE);
-    CHECK_GE(sysconf_result, 0);
-    size_t pagesize = static_cast<size_t>(sysconf_result);
-    CHECK_GE(sizeof(pagesize), sizeof(sysconf_result));
-    void *mapping = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0);
-    if (mapping != MAP_FAILED) {
-      if (mprotect(mapping, pagesize, PROT_READ | PROT_EXEC) == 0)
-        result = true;
-      munmap(mapping, pagesize);
-    }
-  }
-  return result;
-}
-
-};  // namespace
-#endif  // defined(OS_LINUX)
-
-bool GetShmemTempDir(FilePath* path, bool executable) {
-#if defined(OS_LINUX)
-  bool use_dev_shm = true;
-  if (executable) {
-    static const bool s_dev_shm_executable = DetermineDevShmExecutable();
-    use_dev_shm = s_dev_shm_executable;
-  }
-  if (use_dev_shm) {
-    *path = FilePath("/dev/shm");
-    return true;
-  }
-#endif
-  return GetTempDir(path);
-}
-#endif  // !defined(OS_ANDROID)
-
-FilePath GetHomeDir() {
-#if defined(OS_CHROMEOS)
-  if (base::SysInfo::IsRunningOnChromeOS())
-    return FilePath("/home/chronos/user");
-#endif
-
-  const char* home_dir = getenv("HOME");
-  if (home_dir && home_dir[0])
-    return FilePath(home_dir);
-
-#if defined(OS_ANDROID)
-  DLOG(WARNING) << "OS_ANDROID: Home directory lookup not yet implemented.";
-#elif defined(USE_GLIB) && !defined(OS_CHROMEOS)
-  // g_get_home_dir calls getpwent, which can fall through to LDAP calls.
-  base::ThreadRestrictions::AssertIOAllowed();
-
-  home_dir = g_get_home_dir();
-  if (home_dir && home_dir[0])
-    return FilePath(home_dir);
-#endif
-
-  FilePath rv;
-  if (file_util::GetTempDir(&rv))
-    return rv;
-
-  // Last resort.
-  return FilePath("/tmp");
-}
-#endif  // !defined(OS_MACOSX)
-
 bool VerifyPathControlledByUser(const FilePath& base,
                                 const FilePath& path,
                                 uid_t owner_uid,