[Debugger] Use FileSystem instead of calling llvm::sys::fs::openFileForWrite directly.

[JDevlieghere]

Summary

This replaces the (only) call to llvm::sys::fs::openFileForWrite with FileSystem::Open. This guarantees that we include log files in the reproducers.

[jingham]

This looks okay to me though I'm not very familiar with the llvm file system interfaces.

Do we have any tests that tests that log output gets emitted to the file requested when you do "log enable -f somefile whatever"? If so and they still work, LGTM. If we don't test that at all, we should probably add a test on the principle of "when you monkey with something that doesn't have a test, you should add one..."

[JDevlieghere]

In D81499#2086268, @jingham wrote:

This looks okay to me though I'm not very familiar with the llvm file system interfaces.

Do we have any tests that tests that log output gets emitted to the file requested when you do "log enable -f somefile whatever"? If so and they still work, LGTM. If we don't test that at all, we should probably add a test on the principle of "when you monkey with something that doesn't have a test, you should add one..."

Yep, we had two tests that were screaming at me when I messed up :-)

[jingham]

LGTM then.

[yrouban]

Sorry, I have a typo in diff number. My commit relates to https://reviews.llvm.org/D81449.

lldb/source/Core/Debugger.cpp

   } else if (log_file.empty()) {
     log_stream_sp = std::make_shared<llvm::raw_fd_ostream>(
         GetOutputFile().GetDescriptor(), !should_close, unbuffered);
   } else {
     auto pos = m_log_streams.find(log_file);
     if (pos != m_log_streams.end())
       log_stream_sp = pos->second.lock();
     if (!log_stream_sp) {
-      llvm::sys::fs::OpenFlags flags = llvm::sys::fs::OF_Text;
+      File::OpenOptions flags =
+          File::eOpenOptionWrite | File::eOpenOptionCanCreate;
       if (log_options & LLDB_LOG_OPTION_APPEND)
-        flags |= llvm::sys::fs::OF_Append;
-      int FD;
-      if (std::error_code ec = llvm::sys::fs::openFileForWrite(
-              log_file, FD, llvm::sys::fs::CD_CreateAlways, flags)) {
-        error_stream << "Unable to open log file: " << ec.message();
+        flags |= File::eOpenOptionAppend;
+      else
+        flags |= File::eOpenOptionTruncate;
+      auto file = FileSystem::Instance().Open(
+          FileSpec(log_file), flags, lldb::eFilePermissionsFileDefault, false);
+      if (!file) {
+        // FIXME: This gets garbled when called from the log command.
+        error_stream << "Unable to open log file: " << log_file;
         return false;
       }
-      log_stream_sp =
-          std::make_shared<llvm::raw_fd_ostream>(FD, should_close, unbuffered);
+
+      log_stream_sp = std::make_shared<llvm::raw_fd_ostream>(
+          (*file)->GetDescriptor(), should_close, unbuffered);
       m_log_streams[log_file] = log_stream_sp;
     }
   }
   assert(log_stream_sp);
 
   if (log_options == 0)
     log_options =
         LLDB_LOG_OPTION_PREPEND_THREAD_NAME | LLDB_LOG_OPTION_THREADSAFE;