Mercurial > vim
view src/arabic.c @ 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 | 7334bf933510 |
children |
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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. * See README.txt for an overview of the Vim source code. */ /* * arabic.c: functions for Arabic language * * Author: Nadim Shaikli & Isam Bayazidi * Farsi support and restructuring to make adding new letters easier by Ali * Gholami Rudi. Further work by Ameretat Reith. */ /* * Sorted list of unicode Arabic characters. Each entry holds the * presentation forms of a letter. * * Arabic characters are categorized into following types: * * Isolated - iso-8859-6 form * Initial - unicode form-B start * Medial - unicode form-B middle * Final - unicode form-B final * Stand-Alone - unicode form-B isolated */ #include "vim.h" #if defined(FEAT_ARABIC) || defined(PROTO) // Unicode values for Arabic characters. #define a_HAMZA 0x0621 #define a_ALEF_MADDA 0x0622 #define a_ALEF_HAMZA_ABOVE 0x0623 #define a_WAW_HAMZA 0x0624 #define a_ALEF_HAMZA_BELOW 0x0625 #define a_YEH_HAMZA 0x0626 #define a_ALEF 0x0627 #define a_BEH 0x0628 #define a_TEH_MARBUTA 0x0629 #define a_TEH 0x062a #define a_THEH 0x062b #define a_JEEM 0x062c #define a_HAH 0x062d #define a_KHAH 0x062e #define a_DAL 0x062f #define a_THAL 0x0630 #define a_REH 0x0631 #define a_ZAIN 0x0632 #define a_SEEN 0x0633 #define a_SHEEN 0x0634 #define a_SAD 0x0635 #define a_DAD 0x0636 #define a_TAH 0x0637 #define a_ZAH 0x0638 #define a_AIN 0x0639 #define a_GHAIN 0x063a #define a_TATWEEL 0x0640 #define a_FEH 0x0641 #define a_QAF 0x0642 #define a_KAF 0x0643 #define a_LAM 0x0644 #define a_MEEM 0x0645 #define a_NOON 0x0646 #define a_HEH 0x0647 #define a_WAW 0x0648 #define a_ALEF_MAKSURA 0x0649 #define a_YEH 0x064a #define a_FATHATAN 0x064b #define a_DAMMATAN 0x064c #define a_KASRATAN 0x064d #define a_FATHA 0x064e #define a_DAMMA 0x064f #define a_KASRA 0x0650 #define a_SHADDA 0x0651 #define a_SUKUN 0x0652 #define a_MADDA_ABOVE 0x0653 #define a_HAMZA_ABOVE 0x0654 #define a_HAMZA_BELOW 0x0655 #define a_PEH 0x067e #define a_TCHEH 0x0686 #define a_JEH 0x0698 #define a_FKAF 0x06a9 #define a_GAF 0x06af #define a_FYEH 0x06cc #define a_s_LAM_ALEF_MADDA_ABOVE 0xfef5 #define a_f_LAM_ALEF_MADDA_ABOVE 0xfef6 #define a_s_LAM_ALEF_HAMZA_ABOVE 0xfef7 #define a_f_LAM_ALEF_HAMZA_ABOVE 0xfef8 #define a_s_LAM_ALEF_HAMZA_BELOW 0xfef9 #define a_f_LAM_ALEF_HAMZA_BELOW 0xfefa #define a_s_LAM_ALEF 0xfefb #define a_f_LAM_ALEF 0xfefc static struct achar { unsigned c; unsigned isolated; unsigned initial; unsigned medial; unsigned final; } achars[] = { {a_HAMZA, 0xfe80, 0, 0, 0}, {a_ALEF_MADDA, 0xfe81, 0, 0, 0xfe82}, {a_ALEF_HAMZA_ABOVE, 0xfe83, 0, 0, 0xfe84}, {a_WAW_HAMZA, 0xfe85, 0, 0, 0xfe86}, {a_ALEF_HAMZA_BELOW, 0xfe87, 0, 0, 0xfe88}, {a_YEH_HAMZA, 0xfe89, 0xfe8b, 0xfe8c, 0xfe8a}, {a_ALEF, 0xfe8d, 0, 0, 0xfe8e}, {a_BEH, 0xfe8f, 0xfe91, 0xfe92, 0xfe90}, {a_TEH_MARBUTA, 0xfe93, 0, 0, 0xfe94}, {a_TEH, 0xfe95, 0xfe97, 0xfe98, 0xfe96}, {a_THEH, 0xfe99, 0xfe9b, 0xfe9c, 0xfe9a}, {a_JEEM, 0xfe9d, 0xfe9f, 0xfea0, 0xfe9e}, {a_HAH, 0xfea1, 0xfea3, 0xfea4, 0xfea2}, {a_KHAH, 0xfea5, 0xfea7, 0xfea8, 0xfea6}, {a_DAL, 0xfea9, 0, 0, 0xfeaa}, {a_THAL, 0xfeab, 0, 0, 0xfeac}, {a_REH, 0xfead, 0, 0, 0xfeae}, {a_ZAIN, 0xfeaf, 0, 0, 0xfeb0}, {a_SEEN, 0xfeb1, 0xfeb3, 0xfeb4, 0xfeb2}, {a_SHEEN, 0xfeb5, 0xfeb7, 0xfeb8, 0xfeb6}, {a_SAD, 0xfeb9, 0xfebb, 0xfebc, 0xfeba}, {a_DAD, 0xfebd, 0xfebf, 0xfec0, 0xfebe}, {a_TAH, 0xfec1, 0xfec3, 0xfec4, 0xfec2}, {a_ZAH, 0xfec5, 0xfec7, 0xfec8, 0xfec6}, {a_AIN, 0xfec9, 0xfecb, 0xfecc, 0xfeca}, {a_GHAIN, 0xfecd, 0xfecf, 0xfed0, 0xfece}, {a_TATWEEL, 0, 0x0640, 0x0640, 0x0640}, {a_FEH, 0xfed1, 0xfed3, 0xfed4, 0xfed2}, {a_QAF, 0xfed5, 0xfed7, 0xfed8, 0xfed6}, {a_KAF, 0xfed9, 0xfedb, 0xfedc, 0xfeda}, {a_LAM, 0xfedd, 0xfedf, 0xfee0, 0xfede}, {a_MEEM, 0xfee1, 0xfee3, 0xfee4, 0xfee2}, {a_NOON, 0xfee5, 0xfee7, 0xfee8, 0xfee6}, {a_HEH, 0xfee9, 0xfeeb, 0xfeec, 0xfeea}, {a_WAW, 0xfeed, 0, 0, 0xfeee}, {a_ALEF_MAKSURA, 0xfeef, 0, 0, 0xfef0}, {a_YEH, 0xfef1, 0xfef3, 0xfef4, 0xfef2}, {a_FATHATAN, 0xfe70, 0, 0, 0}, {a_DAMMATAN, 0xfe72, 0, 0, 0}, {a_KASRATAN, 0xfe74, 0, 0, 0}, {a_FATHA, 0xfe76, 0, 0xfe77, 0}, {a_DAMMA, 0xfe78, 0, 0xfe79, 0}, {a_KASRA, 0xfe7a, 0, 0xfe7b, 0}, {a_SHADDA, 0xfe7c, 0, 0xfe7c, 0}, {a_SUKUN, 0xfe7e, 0, 0xfe7f, 0}, {a_MADDA_ABOVE, 0, 0, 0, 0}, {a_HAMZA_ABOVE, 0, 0, 0, 0}, {a_HAMZA_BELOW, 0, 0, 0, 0}, {a_PEH, 0xfb56, 0xfb58, 0xfb59, 0xfb57}, {a_TCHEH, 0xfb7a, 0xfb7c, 0xfb7d, 0xfb7b}, {a_JEH, 0xfb8a, 0, 0, 0xfb8b}, {a_FKAF, 0xfb8e, 0xfb90, 0xfb91, 0xfb8f}, {a_GAF, 0xfb92, 0xfb94, 0xfb95, 0xfb93}, {a_FYEH, 0xfbfc, 0xfbfe, 0xfbff, 0xfbfd}, }; #define a_BYTE_ORDER_MARK 0xfeff /* * Find the struct achar pointer to the given Arabic char. * Returns NULL if not found. */ static struct achar * find_achar(int c) { int h, m, l; // using binary search to find c h = ARRAY_LENGTH(achars); l = 0; while (l < h) { m = (h + l) / 2; if (achars[m].c == (unsigned)c) return &achars[m]; if ((unsigned)c < achars[m].c) h = m; else l = m + 1; } return NULL; } /* * Change shape - from Combination (2 char) to an Isolated */ static int chg_c_laa2i(int hid_c) { int tempc; switch (hid_c) { case a_ALEF_MADDA: tempc = a_s_LAM_ALEF_MADDA_ABOVE; break; case a_ALEF_HAMZA_ABOVE: tempc = a_s_LAM_ALEF_HAMZA_ABOVE; break; case a_ALEF_HAMZA_BELOW: tempc = a_s_LAM_ALEF_HAMZA_BELOW; break; case a_ALEF: tempc = a_s_LAM_ALEF; break; default: tempc = 0; } return tempc; } /* * Change shape - from Combination-Isolated to Final */ static int chg_c_laa2f(int hid_c) { int tempc; switch (hid_c) { case a_ALEF_MADDA: tempc = a_f_LAM_ALEF_MADDA_ABOVE; break; case a_ALEF_HAMZA_ABOVE: tempc = a_f_LAM_ALEF_HAMZA_ABOVE; break; case a_ALEF_HAMZA_BELOW: tempc = a_f_LAM_ALEF_HAMZA_BELOW; break; case a_ALEF: tempc = a_f_LAM_ALEF; break; default: tempc = 0; } return tempc; } /* * Returns whether it is possible to join the given letters */ static int can_join(int c1, int c2) { struct achar *a1 = find_achar(c1); struct achar *a2 = find_achar(c2); return a1 && a2 && (a1->initial || a1->medial) && (a2->final || a2->medial); } /* * Check whether we are dealing with a character that could be regarded as an * Arabic combining character, need to check the character before this. */ int arabic_maycombine(int two) { if (p_arshape && !p_tbidi) return (two == a_ALEF_MADDA || two == a_ALEF_HAMZA_ABOVE || two == a_ALEF_HAMZA_BELOW || two == a_ALEF); return FALSE; } /* * Check whether we are dealing with Arabic combining characters. * Note: these are NOT really composing characters! */ int arabic_combine( int one, // first character int two) // character just after "one" { if (one == a_LAM) return arabic_maycombine(two); return FALSE; } /* * A_is_iso returns true if 'c' is an Arabic ISO-8859-6 character * (alphabet/number/punctuation) */ static int A_is_iso(int c) { return find_achar(c) != NULL; } /* * A_is_ok returns true if 'c' is an Arabic 10646 (8859-6 or Form-B) */ static int A_is_ok(int c) { return (A_is_iso(c) || c == a_BYTE_ORDER_MARK); } /* * A_is_valid returns true if 'c' is an Arabic 10646 (8859-6 or Form-B) * with some exceptions/exclusions */ static int A_is_valid(int c) { return (A_is_ok(c) && c != a_HAMZA); } /* * Do Arabic shaping on character "c". Returns the shaped character. * out: "ccp" points to the first byte of the character to be shaped. * in/out: "c1p" points to the first composing char for "c". * in: "prev_c" is the previous character (not shaped) * in: "prev_c1" is the first composing char for the previous char * (not shaped) * in: "next_c" is the next character (not shaped). */ int arabic_shape( int c, int *ccp, int *c1p, int prev_c, int prev_c1, int next_c) { int curr_c; int curr_laa; int prev_laa; // Deal only with Arabic characters, pass back all others if (!A_is_ok(c)) return c; curr_laa = arabic_combine(c, *c1p); prev_laa = arabic_combine(prev_c, prev_c1); if (curr_laa) { if (A_is_valid(prev_c) && can_join(prev_c, a_LAM) && !prev_laa) curr_c = chg_c_laa2f(*c1p); else curr_c = chg_c_laa2i(*c1p); // Remove the composing character *c1p = 0; } else { struct achar *curr_a = find_achar(c); int backward_combine = !prev_laa && can_join(prev_c, c); int forward_combine = can_join(c, next_c); if (backward_combine) { if (forward_combine) curr_c = curr_a->medial; else curr_c = curr_a->final; } else { if (forward_combine) curr_c = curr_a->initial; else curr_c = curr_a->isolated; } } // Character missing from the table means using original character. if (curr_c == NUL) curr_c = c; if (curr_c != c && ccp != NULL) { char_u buf[MB_MAXBYTES + 1]; // Update the first byte of the character. (*mb_char2bytes)(curr_c, buf); *ccp = buf[0]; } // Return the shaped character return curr_c; } #endif // FEAT_ARABIC