Mercurial > vim
view src/termdefs.h @ 32936:c517845bd10e v9.0.1776
patch 9.0.1776: No support for stable Python 3 ABI
Commit: https://github.com/vim/vim/commit/c13b3d1350b60b94fe87f0761ea31c0e7fb6ebf3
Author: Yee Cheng Chin <ychin.git@gmail.com>
Date: Sun Aug 20 21:18:38 2023 +0200
patch 9.0.1776: No support for stable Python 3 ABI
Problem: No support for stable Python 3 ABI
Solution: Support Python 3 stable ABI
Commits:
1) Support Python 3 stable ABI to allow mixed version interoperatbility
Vim currently supports embedding Python for use with plugins, and the
"dynamic" linking option allows the user to specify a locally installed
version of Python by setting `pythonthreedll`. However, one caveat is
that the Python 3 libs are not binary compatible across minor versions,
and mixing versions can potentially be dangerous (e.g. let's say Vim was
linked against the Python 3.10 SDK, but the user sets `pythonthreedll`
to a 3.11 lib). Usually, nothing bad happens, but in theory this could
lead to crashes, memory corruption, and other unpredictable behaviors.
It's also difficult for the user to tell something is wrong because Vim
has no way of reporting what Python 3 version Vim was linked with.
For Vim installed via a package manager, this usually isn't an issue
because all the dependencies would already be figured out. For prebuilt
Vim binaries like MacVim (my motivation for working on this), AppImage,
and Win32 installer this could potentially be an issue as usually a
single binary is distributed. This is more tricky when a new Python
version is released, as there's a chicken-and-egg issue with deciding
what Python version to build against and hard to keep in sync when a new
Python version just drops and we have a mix of users of different Python
versions, and a user just blindly upgrading to a new Python could lead to
bad interactions with Vim.
Python 3 does have a solution for this problem: stable ABI / limited API
(see https://docs.python.org/3/c-api/stable.html). The C SDK limits the
API to a set of functions that are promised to be stable across
versions. This pull request adds an ifdef config that allows us to turn
it on when building Vim. Vim binaries built with this option should be
safe to freely link with any Python 3 libraies without having the
constraint of having to use the same minor version.
Note: Python 2 has no such concept and this doesn't change how Python 2
integration works (not that there is going to be a new version of Python
2 that would cause compatibility issues in the future anyway).
---
Technical details:
======
The stable ABI can be accessed when we compile with the Python 3 limited
API (by defining `Py_LIMITED_API`). The Python 3 code (in `if_python3.c`
and `if_py_both.h`) would now handle this and switch to limited API
mode. Without it set, Vim will still use the full API as before so this
is an opt-in change.
The main difference is that `PyType_Object` is now an opaque struct that
we can't directly create "static types" out of, and we have to create
type objects as "heap types" instead. This is because the struct is not
stable and changes from version to version (e.g. 3.8 added a
`tp_vectorcall` field to it). I had to change all the types to be
allocated on the heap instead with just a pointer to them.
Other functions are also simply missing in limited API, or they are
introduced too late (e.g. `PyUnicode_AsUTF8AndSize` in 3.10) to it that
we need some other ways to do the same thing, so I had to abstract a few
things into macros, and sometimes re-implement functions like
`PyObject_NEW`.
One caveat is that in limited API, `OutputType` (used for replacing
`sys.stdout`) no longer inherits from `PyStdPrinter_Type` which I don't
think has any real issue other than minor differences in how they
convert to a string and missing a couple functions like `mode()` and
`fileno()`.
Also fixed an existing bug where `tp_basicsize` was set incorrectly for
`BufferObject`, `TabListObject, `WinListObject`.
Technically, there could be a small performance drop, there is a little
more indirection with accessing type objects, and some APIs like
`PyUnicode_AsUTF8AndSize` are missing, but in practice I didn't see any
difference, and any well-written Python plugin should try to avoid
excessing callbacks to the `vim` module in Python anyway.
I only tested limited API mode down to Python 3.7, which seemes to
compile and work fine. I haven't tried earlier Python versions.
2) Fix PyIter_Check on older Python vers / type##Ptr unused warning
For PyIter_Check, older versions exposed them as either macros (used in
full API), or a function (for use in limited API). A previous change
exposed PyIter_Check to the dynamic build because Python just moved it
to function-only in 3.10 anyway. Because of that, just make sure we
always grab the function in dynamic builds in earlier versions since
that's what Python eventually did anyway.
3) Move Py_LIMITED_API define to configure script
Can now use --with-python-stable-abi flag to customize what stable ABI
version to target. Can also use an env var to do so as well.
4) Show +python/dyn-stable in :version, and allow has() feature query
Not sure if the "/dyn-stable" suffix would break things, or whether we
should do it another way. Or just don't show it in version and rely on
has() feature checking.
5) Documentation first draft. Still need to implement v:python3_version
6) Fix PyIter_Check build breaks when compiling against Python 3.8
7) Add CI coverage stable ABI on Linux/Windows / make configurable on Windows
This adds configurable options for Windows make files (both MinGW and
MSVC). CI will also now exercise both traditional full API and stable
ABI for Linux and Windows in the matrix for coverage.
Also added a "dynamic" option to Linux matrix as a drive-by change to
make other scripting languages like Ruby / Perl testable under both
static and dynamic builds.
8) Fix inaccuracy in Windows docs
Python's own docs are confusing but you don't actually want to use
`python3.dll` for the dynamic linkage.
9) Add generated autoconf file
10) Add v:python3_version support
This variable indicates the version of Python3 that Vim was built
against (PY_VERSION_HEX), and will be useful to check whether the Python
library you are loading in dynamically actually fits it. When built with
stable ABI, it will be the limited ABI version instead
(`Py_LIMITED_API`), which indicates the minimum version of Python 3 the
user should have, rather than the exact match. When stable ABI is used,
we won't be exposing PY_VERSION_HEX in this var because it just doesn't
seem necessary to do so (the whole point of stable ABI is the promise
that it will work across versions), and I don't want to confuse the user
with too many variables.
Also, cleaned up some documentation, and added help tags.
11) Fix Python 3.7 compat issues
Fix a couple issues when using limited API < 3.8
- Crash on exit: In Python 3.7, if a heap-allocated type is destroyed
before all instances are, it would cause a crash later. This happens
when we destroyed `OptionsType` before calling `Py_Finalize` when
using the limited API. To make it worse, later versions changed the
semantics and now each instance has a strong reference to its own type
and the recommendation has changed to have each instance de-ref its
own type and have its type in GC traversal. To avoid dealing with
these cross-version variations, we just don't free the heap type. They
are static types in non-limited-API anyway and are designed to last
through the entirety of the app, and we also don't restart the Python
runtime and therefore do not need it to have absolutely 0 leaks.
See:
- https://docs.python.org/3/whatsnew/3.8.html#changes-in-the-c-api
- https://docs.python.org/3/whatsnew/3.9.html#changes-in-the-c-api
- PyIter_Check: This function is not provided in limited APIs older than
3.8. Previously I was trying to mock it out using manual
PyType_GetSlot() but it was brittle and also does not actually work
properly for static types (it will generate a Python error). Just
return false. It does mean using limited API < 3.8 is not recommended
as you lose the functionality to handle iterators, but from playing
with plugins I couldn't find it to be an issue.
- Fix loading of PyIter_Check so it will be done when limited API < 3.8.
Otherwise loading a 3.7 Python lib will fail even if limited API was
specified to use it.
12) Make sure to only load `PyUnicode_AsUTF8AndSize` in needed in limited API
We don't use this function unless limited API >= 3.10, but we were
loading it regardless. Usually it's ok in Unix-like systems where Python
just has a single lib that we load from, but in Windows where there is a
separate python3.dll this would not work as the symbol would not have
been exposed in this more limited DLL file. This makes it much clearer
under what condition is this function needed.
closes: #12032
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
| author | Christian Brabandt <cb@256bit.org> |
|---|---|
| date | Sun, 20 Aug 2023 21:30:04 +0200 |
| parents | 533e36e02a68 |
| children | 36843e079f64 |
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/* vi:set ts=8 sts=4 sw=4 noet: * * VIM - Vi IMproved by Bram Moolenaar * * Do ":help uganda" in Vim to read copying and usage conditions. * Do ":help credits" in Vim to see a list of people who contributed. */ /* * This file contains the defines for the machine dependent escape sequences * that the editor needs to perform various operations. All of the sequences * here are optional, except "cm" (cursor motion). */ #if defined(SASC) && SASC < 658 /* * The SAS C compiler has a bug that makes typedefs being forgotten * in include files. Has been fixed in version 6.58. */ typedef unsigned char char_u; #endif /* * Index of the termcap codes in the term_strings array. */ enum SpecialKey { KS_NAME = 0,// name of this terminal entry KS_CE, // clear to end of line KS_AL, // add new blank line KS_CAL, // add number of blank lines KS_DL, // delete line KS_CDL, // delete number of lines KS_CS, // scroll region KS_CL, // clear screen KS_CD, // clear to end of display KS_UT, // clearing uses current background color KS_DA, // text may be scrolled down from up KS_DB, // text may be scrolled up from down KS_VI, // cursor invisible KS_VE, // cursor visible KS_VS, // cursor very visible (blink) KS_CVS, // cursor normally visible (no blink) KS_CSH, // cursor shape KS_CRC, // request cursor blinking KS_CRS, // request cursor style KS_ME, // normal mode KS_MR, // reverse mode KS_MD, // bold mode KS_SE, // normal mode KS_SO, // standout mode KS_CZH, // italic mode start KS_CZR, // italic mode end KS_UE, // exit underscore (underline) mode KS_US, // underscore (underline) mode KS_UCE, // exit undercurl mode KS_UCS, // undercurl mode KS_USS, // double underline mode KS_DS, // dotted underline mode KS_CDS, // dashed underline mode KS_STE, // exit strikethrough mode KS_STS, // strikethrough mode KS_MS, // save to move cur in reverse mode KS_CM, // cursor motion KS_SR, // scroll reverse (backward) KS_CRI, // cursor number of chars right KS_VB, // visual bell KS_KS, // put term in "keypad transmit" mode KS_KE, // out of "keypad transmit" mode KS_TI, // put terminal in termcap mode KS_CTI, // put terminal in "raw" mode KS_CRK, // request keyboard protocol state KS_TE, // end of termcap mode KS_CTE, // end of "raw" mode KS_BC, // backspace character (cursor left) KS_CCS, // cur is relative to scroll region KS_CCO, // number of colors KS_CSF, // set foreground color KS_CSB, // set background color KS_XS, // standout not erased by overwriting (hpterm) KS_XN, // newline glitch KS_MB, // blink mode KS_CAF, // set foreground color (ANSI) KS_CAB, // set background color (ANSI) KS_CAU, // set underline color (ANSI) KS_LE, // cursor left (mostly backspace) KS_ND, // cursor right KS_CIS, // set icon text start KS_CIE, // set icon text end KS_CSC, // set cursor color start KS_CEC, // set cursor color end KS_TS, // set window title start (to status line) KS_FS, // set window title end (from status line) KS_CWP, // set window position in pixels KS_CGP, // get window position KS_CWS, // set window size in characters KS_CRV, // request version string KS_CXM, // enable/disable mouse reporting KS_RFG, // request foreground color KS_RBG, // request background color KS_CSI, // start insert mode (bar cursor) KS_CEI, // end insert mode (block cursor) KS_CSR, // start replace mode (underline cursor) KS_CSV, // scroll region vertical KS_OP, // original color pair KS_U7, // request cursor position KS_8F, // set foreground color (RGB) KS_8B, // set background color (RGB) KS_8U, // set underline color (RGB) KS_CBE, // enable bracketed paste mode KS_CBD, // disable bracketed paste mode KS_CST, // save window title KS_CRT, // restore window title KS_SSI, // save icon text KS_SRI, // restore icon text KS_FD, // disable focus event tracking KS_FE // enable focus event tracking }; #define KS_LAST KS_FE /* * the terminal capabilities are stored in this array * IMPORTANT: When making changes, note the following: * - there should be an entry for each code in the builtin termcaps * - there should be an option for each code in option.c * - there should be code in term.c to obtain the value from the termcap */ extern char_u *(term_strings[]); // current terminal strings /* * strings used for terminal */ #define T_NAME (TERM_STR(KS_NAME)) // terminal name #define T_CE (TERM_STR(KS_CE)) // clear to end of line #define T_AL (TERM_STR(KS_AL)) // add new blank line #define T_CAL (TERM_STR(KS_CAL)) // add number of blank lines #define T_DL (TERM_STR(KS_DL)) // delete line #define T_CDL (TERM_STR(KS_CDL)) // delete number of lines #define T_CS (TERM_STR(KS_CS)) // scroll region #define T_CSV (TERM_STR(KS_CSV)) // scroll region vertical #define T_CL (TERM_STR(KS_CL)) // clear screen #define T_CD (TERM_STR(KS_CD)) // clear to end of display #define T_UT (TERM_STR(KS_UT)) // clearing uses background color #define T_DA (TERM_STR(KS_DA)) // text may be scrolled down from up #define T_DB (TERM_STR(KS_DB)) // text may be scrolled up from down #define T_VI (TERM_STR(KS_VI)) // cursor invisible #define T_VE (TERM_STR(KS_VE)) // cursor visible #define T_VS (TERM_STR(KS_VS)) // cursor very visible (blink) #define T_CVS (TERM_STR(KS_CVS)) // cursor normally visible (no blink) #define T_CSH (TERM_STR(KS_CSH)) // cursor shape #define T_CRC (TERM_STR(KS_CRC)) // request cursor blinking #define T_CRS (TERM_STR(KS_CRS)) // request cursor style #define T_ME (TERM_STR(KS_ME)) // normal mode #define T_MR (TERM_STR(KS_MR)) // reverse mode #define T_MD (TERM_STR(KS_MD)) // bold mode #define T_SE (TERM_STR(KS_SE)) // normal mode #define T_SO (TERM_STR(KS_SO)) // standout mode #define T_CZH (TERM_STR(KS_CZH)) // italic mode start #define T_CZR (TERM_STR(KS_CZR)) // italic mode end #define T_UE (TERM_STR(KS_UE)) // exit underscore (underline) mode #define T_US (TERM_STR(KS_US)) // underscore (underline) mode #define T_UCE (TERM_STR(KS_UCE)) // exit undercurl mode #define T_UCS (TERM_STR(KS_UCS)) // undercurl mode #define T_USS (TERM_STR(KS_USS)) // double underline mode #define T_DS (TERM_STR(KS_DS)) // dotted underline mode #define T_CDS (TERM_STR(KS_CDS)) // dashed underline mode #define T_STE (TERM_STR(KS_STE)) // exit strikethrough mode #define T_STS (TERM_STR(KS_STS)) // strikethrough mode #define T_MS (TERM_STR(KS_MS)) // save to move cur in reverse mode #define T_CM (TERM_STR(KS_CM)) // cursor motion #define T_SR (TERM_STR(KS_SR)) // scroll reverse (backward) #define T_CRI (TERM_STR(KS_CRI)) // cursor number of chars right #define T_VB (TERM_STR(KS_VB)) // visual bell #define T_KS (TERM_STR(KS_KS)) // put term in "keypad transmit" mode #define T_KE (TERM_STR(KS_KE)) // out of "keypad transmit" mode #define T_TI (TERM_STR(KS_TI)) // put terminal in termcap mode #define T_CTI (TERM_STR(KS_CTI)) // put terminal in "raw" mode #define T_CRK (TERM_STR(KS_CRK)) // request keyboard protocol status #define T_TE (TERM_STR(KS_TE)) // end of termcap mode #define T_CTE (TERM_STR(KS_CTE)) // end of "raw" mode #define T_BC (TERM_STR(KS_BC)) // backspace character #define T_CCS (TERM_STR(KS_CCS)) // cur is relative to scroll region #define T_CCO (TERM_STR(KS_CCO)) // number of colors #define T_CSF (TERM_STR(KS_CSF)) // set foreground color #define T_CSB (TERM_STR(KS_CSB)) // set background color #define T_XS (TERM_STR(KS_XS)) // standout not erased by overwriting #define T_XN (TERM_STR(KS_XN)) // newline glitch #define T_MB (TERM_STR(KS_MB)) // blink mode #define T_CAF (TERM_STR(KS_CAF)) // set foreground color (ANSI) #define T_CAB (TERM_STR(KS_CAB)) // set background color (ANSI) #define T_CAU (TERM_STR(KS_CAU)) // set underline color (ANSI) #define T_LE (TERM_STR(KS_LE)) // cursor left #define T_ND (TERM_STR(KS_ND)) // cursor right #define T_CIS (TERM_STR(KS_CIS)) // set icon text start #define T_CIE (TERM_STR(KS_CIE)) // set icon text end #define T_TS (TERM_STR(KS_TS)) // set window title start #define T_FS (TERM_STR(KS_FS)) // set window title end #define T_CSC (TERM_STR(KS_CSC)) // set cursor color start #define T_CEC (TERM_STR(KS_CEC)) // set cursor color end #define T_CWP (TERM_STR(KS_CWP)) // set window position #define T_CGP (TERM_STR(KS_CGP)) // get window position #define T_CWS (TERM_STR(KS_CWS)) // window size #define T_CSI (TERM_STR(KS_CSI)) // start insert mode #define T_CEI (TERM_STR(KS_CEI)) // end insert mode #define T_CSR (TERM_STR(KS_CSR)) // start replace mode #define T_CRV (TERM_STR(KS_CRV)) // request version string #define T_CXM (TERM_STR(KS_CXM)) // enable/disable mouse reporting #define T_RFG (TERM_STR(KS_RFG)) // request foreground RGB #define T_RBG (TERM_STR(KS_RBG)) // request background RGB #define T_OP (TERM_STR(KS_OP)) // original color pair #define T_U7 (TERM_STR(KS_U7)) // request cursor position #define T_8F (TERM_STR(KS_8F)) // set foreground color (RGB) #define T_8B (TERM_STR(KS_8B)) // set background color (RGB) #define T_8U (TERM_STR(KS_8U)) // set underline color (RGB) #define T_BE (TERM_STR(KS_CBE)) // enable bracketed paste mode #define T_BD (TERM_STR(KS_CBD)) // disable bracketed paste mode #define T_CST (TERM_STR(KS_CST)) // save window title #define T_CRT (TERM_STR(KS_CRT)) // restore window title #define T_SSI (TERM_STR(KS_SSI)) // save icon text #define T_SRI (TERM_STR(KS_SRI)) // restore icon text #define T_FD (TERM_STR(KS_FD)) // disable focus event tracking #define T_FE (TERM_STR(KS_FE)) // enable focus event tracking typedef enum { TMODE_COOK, // terminal mode for external cmds and Ex mode TMODE_SLEEP, // terminal mode for sleeping (cooked but no echo) TMODE_RAW, // terminal mode for Normal and Insert mode TMODE_UNKNOWN // after executing a shell } tmode_T;