gh-111942: Fix crashes in TextIOWrapper.reconfigure()

[serhiy-storchaka]

• Fix crash when encoding is not string or None.
• Fix crash when both line_buffering and write_through raise exception when converted ti int.
• Add a number of tests for constructor and reconfigure() method with invalid arguments.

• Issue: TextIOWrapper.reconfigure() crashes if encoding is not string or None #111942

[aisk]

textiowrapper_change_encoding is only been called by _io_TextIOWrapper_reconfigure_impl, and it's a clinic function, so I think we can just change the signature of it from:

encoding: object = None 

to:

encoding: str(accept={str, NoneType}) = None 

Then clinic will do the type check. This makes the configure method haves more equal behavior with the constructor, and have better type infomations.

[serhiy-storchaka]

encoding: str(accept={str, NoneType}) = None

It is more complex change, some code uses encoding and errors as PyObject *. It also has side effects for strings with embedded surrogate or null characters.

I plan such changes, but I am not sure that they will be backported. On other hand, the fix for a crash should be backported.

[miss-islington-app]

Thanks @serhiy-storchaka for the PR 🌮🎉.. I'm working now to backport this PR to: 3.11, 3.12.
🐍🍒⛏🤖

[bedevere-app]

GH-112058 is a backport of this pull request to the 3.12 branch.

[bedevere-app]

GH-112059 is a backport of this pull request to the 3.11 branch.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Debian PGO 3.x has failed when building commit ee06fff.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/249/builds/6946) and take a look at the build logs.
4. Check if the failure is related to this commit (ee06fff) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/249/builds/6946

Failed tests:

• test_io

Failed subtests:

• test_constructor - test.test_io.CTextIOWrapperTest.test_constructor

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/var/lib/buildbot/workers/enable-optimizations-bot/3.x.gps-debian-profile-opt.pgo/build/Lib/test/test_io.py", line 2727, in test_constructor t.__init__(b, encoding="utf-8", errors='\udcfe') SystemError: <method 'readable' of '_io.BytesIO' objects> returned a result with an exception set

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Debian Clang LTO + PGO 3.x has failed when building commit ee06fff.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/1084/builds/2603) and take a look at the build logs.
4. Check if the failure is related to this commit (ee06fff) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/1084/builds/2603

Failed tests:

• test_io

Failed subtests:

• test_constructor - test.test_io.CTextIOWrapperTest.test_constructor

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/var/lib/buildbot/workers/arm64-clang/3.x.gps-arm64-debian.clang.lto-pgo/build/Lib/test/test_io.py", line 2727, in test_constructor t.__init__(b, encoding="utf-8", errors='\udcfe') SystemError: <method 'readable' of '_io.BytesIO' objects> returned a result with an exception set

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM Raspbian 3.x has failed when building commit ee06fff.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/424/builds/5401) and take a look at the build logs.
4. Check if the failure is related to this commit (ee06fff) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/424/builds/5401

Failed tests:

• test_io

Summary of the results of the build (if available):

==

Click to see traceback logs

remote: Enumerating objects: 24, done. remote: Counting objects: 4% (1/24) remote: Counting objects: 8% (2/24) remote: Counting objects: 12% (3/24) remote: Counting objects: 16% (4/24) remote: Counting objects: 20% (5/24) remote: Counting objects: 25% (6/24) remote: Counting objects: 29% (7/24) remote: Counting objects: 33% (8/24) remote: Counting objects: 37% (9/24) remote: Counting objects: 41% (10/24) remote: Counting objects: 45% (11/24) remote: Counting objects: 50% (12/24) remote: Counting objects: 54% (13/24) remote: Counting objects: 58% (14/24) remote: Counting objects: 62% (15/24) remote: Counting objects: 66% (16/24) remote: Counting objects: 70% (17/24) remote: Counting objects: 75% (18/24) remote: Counting objects: 79% (19/24) remote: Counting objects: 83% (20/24) remote: Counting objects: 87% (21/24) remote: Counting objects: 91% (22/24) remote: Counting objects: 95% (23/24) remote: Counting objects: 100% (24/24) remote: Counting objects: 100% (24/24), done. remote: Compressing objects: 7% (1/13) remote: Compressing objects: 15% (2/13) remote: Compressing objects: 23% (3/13) remote: Compressing objects: 30% (4/13) remote: Compressing objects: 38% (5/13) remote: Compressing objects: 46% (6/13) remote: Compressing objects: 53% (7/13) remote: Compressing objects: 61% (8/13) remote: Compressing objects: 69% (9/13) remote: Compressing objects: 76% (10/13) remote: Compressing objects: 84% (11/13) remote: Compressing objects: 92% (12/13) remote: Compressing objects: 100% (13/13) remote: Compressing objects: 100% (13/13), done. remote: Total 13 (delta 11), reused 1 (delta 0), pack-reused 0  From https://github.com/python/cpython * branch main -> FETCH_HEAD Note: switching to 'ee06fffd38cb51ce1c045da9d8336d9ce13c318a'. You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by switching back to a branch. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -c with the switch command. Example: git switch -c <new-branch-name> Or undo this operation with: git switch - Turn off this advice by setting config variable advice.detachedHead to false HEAD is now at ee06fffd38 gh-111942: Fix crashes in TextIOWrapper.reconfigure() (GH-111976) Switched to and reset branch 'main' Objects/obmalloc.c: In function ‘py_mimalloc_print_stats’: Objects/obmalloc.c:2733:45: warning: format ‘%zd’ expects argument of type ‘signed size_t’, but argument 3 has type ‘long unsigned int’ [-Wformat=] 2733 | fprintf(out, "Small block threshold = %zd, in %u size classes.\n", |~~^|||int|%ld Objects/obmalloc.c:2735:46: warning: format ‘%zd’ expects argument of type ‘signed size_t’, but argument 3 has type ‘long unsigned int’ [-Wformat=] 2735 | fprintf(out, "Medium block threshold = %zd\n", |~~^|||int|%ld Objects/obmalloc.c:2737:45: warning: format ‘%zd’ expects argument of type ‘signed size_t’, but argument 3 has type ‘long unsigned int’ [-Wformat=] 2737 | fprintf(out, "Large object max size = %zd\n", |~~^|||int|%ld In file included from Python/ceval.c:1020: Python/executor_cases.c.h: In function ‘_PyEval_EvalFrameDefault’: Python/executor_cases.c.h:1734:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 1734 | PyObject *descr = (PyObject *)operand; |^ Python/executor_cases.c.h:2368:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2368 | PyObject *descr = (PyObject *)operand; |^ Python/executor_cases.c.h:2387:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2387 | PyObject *descr = (PyObject *)operand; |^ Python/executor_cases.c.h:2405:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2405 | PyObject *descr = (PyObject *)operand; |^ Python/executor_cases.c.h:2419:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2419 | PyObject *descr = (PyObject *)operand; |^ Python/executor_cases.c.h:2446:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2446 | PyObject *descr = (PyObject *)operand; |^./Modules/_testcapi/heaptype_relative.c: In function ‘make_sized_heaptypes’: ./Modules/_testcapi/heaptype_relative.c:67:28: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] 67 | (unsigned long long)data_ptr, |^make: *** [Makefile:2073: buildbottest] Error 2

[vstinner]

@serhiy-storchaka: test_io now fails if Python is built in release mode.

ERROR: test_constructor (test.test_io.CTextIOWrapperTest.test_constructor) ---------------------------------------------------------------------- UnicodeEncodeError: 'utf-8' codec can't encode character '\udcfe' in position 0: surrogates not allowed The above exception was the direct cause of the following exception: Traceback (most recent call last): File "/home/vstinner/python/main/Lib/test/test_io.py", line 2727, in test_constructor t.__init__(b, encoding="utf-8", errors='\udcfe') SystemError: <method 'readable' of '_io.BytesIO' objects> returned a result with an exception set 

This issue now prevents to make any further change, since Address Sanitizer builds Python in release mode and fails.

[vstinner]

I wrote #112067 to fix the regression.