Change 'bool world_readable' to an enum

More clear at callsites, and relatively important not to accidentally choose the wrong one.

R=mark@chromium.org

Review URL: https://codereview.chromium.org/821483002

tools/generate_dump.cc

@@ -153,7 +153,7 @@ int GenerateDumpMain(int argc, char* argv[]) {
     FileWriter file_writer;
     if (!file_writer.Open(base::FilePath(options.dump_path),
                           FileWriteMode::kTruncateOrCreate,
-                          true)) {
+                          FilePermissions::kWorldReadable)) {
       return EXIT_FAILURE;
     }
 

util/file/file_io.h

@@ -64,6 +64,15 @@ enum class FileWriteMode {
   kCreateOrFail,
 };
 
+//! \brief Determines the permissions bits for files created on POSIX systems.
+enum class FilePermissions : bool {
+  //! \brief Equivalent to `0600`.
+  kOwnerOnly,
+
+  //! \brief Equivalent to `0644`.
+  kWorldReadable,
+};
+
 //! \brief Reads from a file, retrying when interrupted on POSIX or following a
 //!     short read.
 //!
@@ -166,18 +175,18 @@ FileHandle LoggingOpenFileForRead(const base::FilePath& path);
 //!     an error if the operation fails.
 //!
 //! \a write_mode determines the style (truncate, reuse, etc.) that is used to
-//! open the file. On POSIX, if \a world_readable, `0644` will be used as
-//! `mode` permissions bits for `open()`, otherwise `0600` will be used. On
-//! Windows, the file is always opened in binary mode (that is, no CRLF
-//! translation).
+//! open the file. On POSIX, \a permissions determines the value that is passed
+//! as `mode` to `open()`. On Windows, the file is always opened in binary mode
+//! (that is, no CRLF translation).
 //!
 //! \return The newly opened FileHandle, or an invalid FileHandle on failure.
 //!
 //! \sa FileWriteMode
+//! \sa FilePermissions
 //! \sa ScopedFileHandle
 FileHandle LoggingOpenFileForWrite(const base::FilePath& path,
                                    FileWriteMode write_mode,
-                                   bool world_readable);
+                                   FilePermissions permissions);
 
 //! \brief Wraps `lseek()` or `SetFilePointerEx()`. Logs an error if the
 //!     operation fails.

util/file/file_io_posix.cc

@@ -84,7 +84,7 @@ FileHandle LoggingOpenFileForRead(const base::FilePath& path) {
 
 FileHandle LoggingOpenFileForWrite(const base::FilePath& path,
                                    FileWriteMode mode,
-                                   bool world_readable) {
+                                   FilePermissions permissions) {
   int flags = O_WRONLY | O_CREAT;
   // kReuseOrCreate does not need any additional flags.
   if (mode == FileWriteMode::kTruncateOrCreate)
@@ -93,7 +93,9 @@ FileHandle LoggingOpenFileForWrite(const base::FilePath& path,
     flags |= O_EXCL;
 
   int fd = HANDLE_EINTR(
-      open(path.value().c_str(), flags, world_readable ? 0644 : 0600));
+      open(path.value().c_str(),
+           flags,
+           permissions == FilePermissions::kWorldReadable ? 0644 : 0600));
   PLOG_IF(ERROR, fd < 0) << "open " << path.value();
   return fd;
 }

util/file/file_io_win.cc

@@ -83,7 +83,7 @@ FileHandle LoggingOpenFileForRead(const base::FilePath& path) {
 
 FileHandle LoggingOpenFileForWrite(const base::FilePath& path,
                                    FileWriteMode mode,
-                                   bool world_readable) {
+                                   FilePermissions permissions) {
   DWORD disposition = 0;
   switch (mode) {
     case FileWriteMode::kReuseOrCreate:

util/file/file_writer.cc

@@ -45,9 +45,9 @@ FileWriter::~FileWriter() {
 
 bool FileWriter::Open(const base::FilePath& path,
                       FileWriteMode write_mode,
-                      bool world_readable) {
+                      FilePermissions permissions) {
   CHECK(!file_.is_valid());
-  file_.reset(LoggingOpenFileForWrite(path, write_mode, world_readable));
+  file_.reset(LoggingOpenFileForWrite(path, write_mode, permissions));
   return file_.is_valid();
 }
 

util/file/file_writer.h

@@ -91,7 +91,7 @@ class FileWriter : public FileWriterInterface {
   //!     after Close().
   bool Open(const base::FilePath& path,
             FileWriteMode write_mode,
-            bool world_readable);
+            FilePermissions permissions);
 
   //! \brief Wraps CheckedCloseHandle().
   //!