Addition of Unique Ptr type Open interface with implementation

[JRS296]

This Pull request:

Addition of Unique Pointer for TFile::Open -> Creation of Interface and implementation for the same

Changes or fixes:

Enables utilization of Unique Pointer for TFile::Open

Checklist:

• tested changes locally

[phsft-bot]

Can one of the admins verify this patch?

[pcanal]

Suggested change

	static std::unique_ptr<TFile> OpenU(const char *name, Option_t *option = "",
	static std::unique_ptr<TFile> OpenUniquePtr(const char *name, Option_t *option = "",

[Axel-Naumann]

We shall have a naming discussion in Mattermost's I/O channel. I promise that nobody will want to spell OpenUniquePtr :-) And I don't want to see Bronch-style Opan either :-)

[JRS296]

@Axel-Naumann @pcanal Is it fine if we keep it as OpenU for the time being?

[pcanal]

@phsft-bot build

[phsft-bot]

Starting build on ROOT-performance-centos8-multicore/soversion, ROOT-ubuntu2204/nortcxxmod, ROOT-ubuntu2004/python3, mac12arm/cxx20, windows10/default
How to customize builds

[phsft-bot]

Build failed on ROOT-ubuntu2004/python3.
Running on root-ubuntu-2004-1.cern.ch:/home/sftnight/build/workspace/root-pullrequests-build
See console output.

Errors:

• [2023-11-03T21:57:54.290Z] FAILED: io/io/CMakeFiles/RIO.dir/src/TFile.cxx.o
• [2023-11-03T21:57:54.546Z] /usr/include/c++/9/bits/unique_ptr.h:857:30: error: no matching function for call to ‘TFile::TFile(const char**, const char**, const char**, int&, int&)’

[phsft-bot]

Build failed on ROOT-ubuntu2204/nortcxxmod.
Running on root-ubuntu-2204-1.cern.ch:/home/sftnight/build/workspace/root-pullrequests-build
See console output.

Errors:

• [2023-11-03T21:57:03.391Z] /usr/include/c++/11/bits/unique_ptr.h:962:30: error: no matching function for call to ‘TFile::TFile(const char**, const char**, const char**, int&, int&)’

[phsft-bot]

Build failed on ROOT-performance-centos8-multicore/soversion.
Running on olbdw-01.cern.ch:/data/sftnight/workspace/root-pullrequests-build
See console output.

Errors:

• [2023-11-03T22:04:50.155Z] /usr/include/c++/8/bits/unique_ptr.h:835:30: error: no matching function for call to ‘TFile::TFile(const char**, const char**, const char**, int&, int&)’

[phsft-bot]

Build failed on mac12arm/cxx20.
Running on macphsft26.dyndns.cern.ch:/Users/sftnight/build/workspace/root-pullrequests-build
See console output.

Errors:

• [2023-11-03T22:08:52.845Z] FAILED: io/io/CMakeFiles/RIO.dir/src/TFile.cxx.o
• [2023-11-03T22:08:53.150Z] /Library/Developer/CommandLineTools/SDKs/MacOSX13.1.sdk/usr/include/c++/v1/__memory/unique_ptr.h:728:32: error: no matching constructor for initialization of 'TFile'

[phsft-bot]

Build failed on windows10/default.
Running on null:C:\build\workspace\root-pullrequests-build
See console output.

Errors:

• [2023-11-03T22:34:54.792Z] C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.32.31326\include\memory(3423,35): error C2661: 'TFile::TFile': no overloaded function takes 5 arguments [C:\build\workspace\root-pullrequests-build\build\io\io\RIO.vcxproj]

[JRS296]

I've just got the testing framework ready, and will conduct local tests before further review. (Just read the PR code of conduct, my apologies for creating a PR without the local tests)

[JRS296]

@Axel-Naumann I've left a message on the root web channel https://mattermost.web.cern.ch/root/channels/root-io, could you have a look?

[JRS296]

@pcanal Successfully tested changes locally, ready for review 👍

[github-actions]

Test Results

       11 files         11 suites   1d 16h 53m 48s ⏱️
  2 481 tests   2 481 ✔️ 0 💤 0 ❌
26 220 runs  26 220 ✔️ 0 💤 0 ❌

Results for commit a829fc3.

♻️ This comment has been updated with latest results.

[JRS296]

@pcanal I had been running the master branch for tests and builds all this time, and not my patch branch; that's why its been failing the Jekyll build 😅
It should be ready now. My apologies for the repeated reviews.

[JRS296]

@pcanal I had been running the master branch for tests and builds all this time, and not my patch branch; that's why its been failing the Jekyll build 😅 It should be ready now. My apologies for the repeated reviews.

Can I have the review for this change?

[JRS296]

@pcanal For some reason the clang tools is running on a different branch, and is not addressing the latest commit to this branch.. Everything else seems fine.

Also as a side note, should I rebase all of this to a single commit?

[JRS296]

@pcanal Can this be merged? And must I rebase this to clean up the commit history?

[Axel-Naumann]

Thanks @JRS296 ! We need to decide how to proceed; the name we choose will become part of ROOT's API and we need to keep it backward compatible from there on. We will come back to you hopefully tonight (@pcanal )

[JRS296]

Thanks @JRS296 ! We need to decide how to proceed; the name we choose will become part of ROOT's API and we need to keep it backward compatible from there on. We will come back to you hopefully tonight (@pcanal )

@Axel-Naumann Any updates on the naming convention to be used? Also, I'd like to know if there is a possibility for me adding some unit test cases for the newly implemented interface, thanks.

[pcanal]

We are still discussing the names. The current proposal is:

   using TFilePtr = std::unique_ptr<TFile>;

   /// Open a file with `name` for reading.
   ///
   /// \note: Synchronizes multi-threaded accesses through locks.
   static TFilePtr OpenForRead(std::string_view name, const Options_t &opts = Options_t());

   /// Open an existing file with `name` for reading and writing. If a file with
   /// that name does not exist, an invalid RFilePtr will be returned.
   ///
   /// \note: Synchronizes multi-threaded accesses through locks.
   static TFilePtr OpenForUpdate(std::string_view name, const Options_t &opts = Options_t());

   /// Open a file with `name` for reading and writing. Fail (return an invalid
   /// `RFilePtr`) if a file with this name already exists.
   ///
   /// \note: Synchronizes multi-threaded accesses through locks.
   static TFilePtr Create(std::string_view name, const Options_t &opts = Options_t());

   /// Open a file with `name` for reading and writing. If a file with this name
   /// already exists, delete it and create a new one. Else simply create a new file.
   ///
   /// \note: Synchronizes multi-threaded accesses through locks.
   static TFilePtr Recreate(std::string_view name, const Options_t &opts = Options_t());

In the meantime, you should indeed start getting familiar with the testing infrastructure. See io/io/test for some examples.