Mercurial > vim
annotate src/os_vms_fix.com @ 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 | 6e4e0d43b20b |
| children |
| rev | line source |
|---|---|
| 7 | 1 $! |
| 2 $! OS_VMS_FIX.COM | |
| 3 $! Copyright (C) 2000, Stephen P. Wall | |
| 4 $! | |
| 5 $! Filter files for "#if" line continuations using a '\' and convert | |
| 6 $! them to use comments for the continuation. Necessary for VAXC - it | |
| 7 $! doesn't understand the '\'. | |
| 8 $! | |
| 9 $! Yes, this is honkin' ugly code, but I deliberately avoided | |
| 10 $! if ... | |
| 11 $! then | |
| 12 $! .... | |
| 13 $! endif | |
| 14 $! and call/subroutine/endsubroutine constructs, because I can still | |
| 15 $! remember when DCL didn't have them, and I wanted this to be as | |
| 16 $! portable as possible, so... If you want to structure it nicer for | |
| 17 $! your own use, please feel free to do so. However, please only | |
|
15034
6e4e0d43b20b
patch 8.1.0528: various typos in comments
Bram Moolenaar <Bram@vim.org>
parents:
7
diff
changeset
|
18 $! distribute it in its original form. |
| 7 | 19 $! |
| 20 $! I wrote it in DCL for portability and ease of use - a C version | |
| 21 $! would definitely run faster, but then I'd have to deal with compiler | |
| 22 $! differences, and users would have to deal with configuring and | |
| 23 $! building it. With DCL, it runs out-of-the-box. | |
| 24 $! | |
| 25 $! Note that if you use this from a VMS system to modify files on a | |
| 26 $! mounted network drive, f$search() may return only the first matching | |
| 27 $! file when it tries to resolve wildcards. I have been unable to find | |
| 28 $! a way around this. Either copy the files to a local disk, or specify | |
| 29 $! each file individually (Keep in mind if you do this that VMS limits | |
| 30 $! you to eight parameters, so you'll only be able to filter eight files | |
| 31 $! at a time). | |
| 32 $! | |
| 33 $! Ideas... | |
| 34 $! - Use 'search filespec "#","if","\"/mat=and' to quickly eliminate | |
| 35 $! files that definitely don't need filtering. This should speed | |
| 36 $! things up considerable. Reading and writing every line from every | |
| 37 $! file takes quite a bit of time... | |
| 38 $! - Error handling isn't great. Come up with something better.... | |
| 39 $! | |
| 40 $! E-mail addresses: | |
| 41 $! Steve Wall hitched97@velnet.com | |
| 42 $! Zoltan Arpadffy arpadffy@polarhome.com | |
| 43 $! John W. Hamill jhamill3@ford.com | |
| 44 $! | |
| 45 $! Modification History: | |
| 46 $! 13Jul00 SWall Initial Version | |
| 47 $! 14Jul00 ZArpadffy Display usage | |
| 48 $! 06Mar01 JHamill Ctrl-M problem fix | |
| 49 $! | |
| 50 $! If no parameters, or "-h" for a parameter, print usage and exit | |
| 51 $ | |
| 52 $ all = "''p1'''p2'''p3'''p4'''p5'''p6'''p7'''p8'" | |
| 53 $ if (all .nes. "") .and. (p1 .nes. "-h") .and. (p1 .nes. "-H") then goto startup | |
| 54 $ | |
| 55 $ write sys$output "OS_VMS_FIX - DECC->VAXC pre-processor directive convert script" | |
| 56 $ write sys$output "Usage: @OS_VMS_FIX <filename_1> <filename_2> <...>" | |
| 57 $ write sys$output " @OS_VMS_FIX <filename with wildcard> <...>" | |
| 58 $ write sys$output "" | |
| 59 $ write sys$output "Example: @OS_VMS_FIX *.c *.h [.proto]*.pro" | |
| 60 $ write sys$output "Please note, you can define up to 8 parameters." | |
| 61 $ write sys$output "" | |
| 62 $ exit | |
| 63 $ | |
| 64 $! Create an FDL file to convert VFC format files to Stream_LF. | |
| 65 $! VMS OPEN/WRITE command creates VFC files. When VFC files are read | |
| 66 $! out under unix, they appear to have binary data embedded in them. | |
| 67 $! To be friendly, we'll convert them to Stream_LF, which reads just | |
| 68 $! file on unix. | |
| 69 $ | |
| 70 $startup: | |
| 71 $ on control_y then goto stopfdl | |
| 72 $ open/write fdl []convert.fdl | |
| 73 $ write fdl "SYSTEM" | |
| 74 $ write fdl " SOURCE VAX/VMS" | |
| 75 $ write fdl "FILE" | |
| 76 $ write fdl " ORGANIZATION SEQUENTIAL" | |
| 77 $ write fdl "RECORD" | |
| 78 $ write fdl " BLOCK_SPAN YES" | |
| 79 $ write fdl " CARRIAGE_CONTROL CARRIAGE_RETURN" | |
| 80 $ write fdl " FORMAT STREAM" | |
| 81 $ write fdl " SIZE 0" | |
| 82 $ close fdl | |
| 83 $ on control_y then goto endparamloop | |
| 84 $ | |
| 85 $! Some symbols for use later on... | |
| 86 $ | |
| 87 $ spc = "" | |
| 88 $ spc[0,8] = 32 | |
| 89 $ tab = "" | |
| 90 $ tab[0,8] = 9 | |
| 91 $ | |
| 92 $! Scan all positional arguments, do wildcard expansion, and call the | |
| 93 $! filter routine on each resulting filename. | |
| 94 $ | |
| 95 $ cnt = 0 | |
| 96 $paramloop: | |
| 97 $ cnt = cnt + 1 | |
| 98 $ | |
| 99 $! VMS only allows command line parameters P1 - P8, so stop after | |
| 100 $! processing 8 arguments. | |
| 101 $ | |
| 102 $ if cnt .eq. 9 then goto endparamloop | |
| 103 $ | |
| 104 $! Skip any empty parameter. | |
| 105 $ | |
| 106 $ if P'cnt' .eqs. "" then goto paramloop | |
| 107 $ | |
| 108 $! Got a parameter - do wildcard expansion. | |
| 109 $ | |
| 110 $ arg = f$parse(P'cnt') | |
| 111 $ write sys$output "Parsing ''arg'..." | |
| 112 $ last = "" | |
| 113 $fileloop: | |
| 114 $ file = f$search(arg, 1) | |
| 115 $ | |
| 116 $! f$search() returns "" after the last of multiple matches. | |
| 117 $ | |
| 118 $ if file .eqs. "" then goto endfileloop | |
| 119 $ | |
| 120 $! Strip the version number. | |
| 121 $ | |
| 122 $ file = f$parse(file,,,"DEVICE") + f$parse(file,,,"DIRECTORY") + - | |
| 123 f$parse(file,,,"NAME") + f$parse(file,,,"TYPE") | |
| 124 $ | |
| 125 $! f$search() returns the same filename over and over if there are no | |
| 126 $! wildcards in it. | |
| 127 $ | |
| 128 $ if file .eqs. last then goto endfileloop | |
| 129 $ last = file | |
| 130 $ | |
| 131 $! Got a valid file - filter it. | |
| 132 $ | |
| 133 $ gosub filter | |
| 134 $ | |
| 135 $! Reset our error handling. | |
| 136 $ | |
| 137 $ on control_y then goto endparamloop | |
| 138 $ | |
| 139 $! See if there's another matching filename. | |
| 140 $ | |
| 141 $ goto fileloop | |
| 142 $endfileloop: | |
| 143 $ | |
| 144 $! Check for another parameter. | |
| 145 $ | |
| 146 $ goto paramloop | |
| 147 $endparamloop: | |
| 148 $ | |
| 149 $! Finished - delete the FDL file. | |
| 150 $ | |
| 151 $ delete []convert.fdl; | |
| 152 $ | |
| 153 $! So long, and thanks for all the fish... | |
| 154 $ | |
| 155 $ exit | |
| 156 $ | |
| 157 $ | |
| 158 $! User aborted with Control-Y during creation of FDL file. | |
| 159 $! Close the file, delete it, and exit with an error status. | |
| 160 $ | |
| 161 $stopfdl: | |
| 162 $ close fdl | |
| 163 $ delete []convert.fdl; | |
| 164 $ exit %X10000000 | |
| 165 $ | |
| 166 $ | |
| 167 $! Filter a file. | |
| 168 $ | |
| 169 $filter: | |
| 170 $ write sys$output "Filtering ''file'..." | |
| 171 $ | |
| 172 $! Get a temporary filename from the subroutine parameter. | |
| 173 $ | |
| 174 $ tmp = f$parse(file,,,"DEVICE") + f$parse(file,,,"DIRECTORY") + - | |
| 175 "tmp_" + f$parse(file,,,"NAME") + f$parse(file,,,"TYPE") | |
| 176 $ on control_y then goto aborted | |
| 177 $ open /read input 'file' | |
| 178 $ open /write output 'tmp' | |
| 179 $ changed = 0 | |
| 180 $readloop: | |
| 181 $ read/end_of_file=endreadloop/error=readlooperror input line | |
| 182 $ | |
| 183 $! Get the first 3 non-blank character on the line. | |
| 184 $ | |
| 185 $ start = f$extract(0,3,f$edit(line,"COLLAPSE,LOWERCASE")) | |
| 186 $ | |
| 187 $! If the line doesn't start with some form of "#if", just write it to | |
| 188 $! the temp file. | |
| 189 $ | |
| 190 $ if start .nes. "#if" then goto writeit | |
| 191 $chkbkslsh: | |
| 192 $ | |
| 193 $! See if the line ends in a backslash. If not, write it to the temp file. | |
| 194 $ | |
| 195 $ if f$extract(f$length(line)-1,1,line) .nes. "\" then goto writeit | |
| 196 $ | |
| 197 $! Ok, got a line that needs to be modified. Mark this file as changed, | |
| 198 $! then replace the backslash at the end with the beginning of a comment | |
| 199 $! (/*), and write it to the temp file. | |
| 200 $ | |
| 201 $ changed = 1 | |
| 202 $ line = f$extract(0,f$length(line)-1,line) + "/*" | |
| 203 $ write/symbol output line | |
| 204 $ | |
| 205 $! Get another line from the input. | |
| 206 $ | |
| 207 $ read/end_of_file=endreadloop/error=readlooperror input line | |
| 208 $ | |
| 209 $! Grab all the blank space from the beginning of the line. | |
| 210 $ | |
| 211 $ spaces = "" | |
| 212 $spaceloop: | |
| 213 $ if (f$extract(0,1,line) .nes. spc) .and. (f$extract(0,1,line) .nes. tab) - | |
| 214 then goto endspaceloop | |
| 215 $ spaces = spaces + f$extract(0,1,line) | |
| 216 $ line = f$extract(1,f$length(line)-1,line) | |
| 217 $ goto spaceloop | |
| 218 $endspaceloop: | |
| 219 $ | |
| 220 $! Stick an end-comment (*/) after the leading blanks, then go back and | |
| 221 $! check for a trailing backslash again, to catch code that continues | |
| 222 $! across multiple lines. | |
| 223 $ | |
| 224 $ line = spaces + "*/ " + line | |
| 225 $ goto chkbkslsh | |
| 226 $ | |
| 227 $! Write the current line, (will either be an untouched line, or the | |
| 228 $! last line of a continuation) to the temp file, and go back to look | |
| 229 $! for more input. | |
| 230 $! | |
| 231 $writeit: | |
| 232 $ write/symbol output line | |
| 233 $ goto readloop | |
| 234 $ | |
| 235 $! Hit EOF. Close the input & output, and if the file was marked as | |
| 236 $! changed, convert it from VMS VFC format, to the more common Stream_LF | |
| 237 $! format, so it doesn't show up full of garbage if someone tries to | |
| 238 $! edit it on another OS. | |
| 239 $! | |
| 240 $endreadloop: | |
| 241 $ close input | |
| 242 $ close output | |
| 243 $ if changed .eq. 0 then goto nocopy | |
| 244 $ convert 'tmp' 'file' /fdl=[]convert.fdl | |
| 245 $nocopy: | |
| 246 $ delete 'tmp'; | |
| 247 $ | |
| 248 $! Exit this subroutine. | |
| 249 $ | |
| 250 $ goto endfunc | |
| 251 $ | |
| 252 $! Got a read error. Say so, and trash the temp file. | |
| 253 $ | |
| 254 $readlooperror: | |
| 255 $ write sys$error "Error processing file ''file'" | |
| 256 $ goto errorend | |
| 257 $ | |
| 258 $! Got an interrupt. Say so, and trash the temp file. | |
| 259 $ | |
| 260 $aborted: | |
| 261 $ write sys$error "Aborted while processing file ''file'" | |
| 262 $ | |
| 263 $! Common code for read errors and interrupts. | |
| 264 $ | |
| 265 $errorend: | |
| 266 $ close input | |
| 267 $ close output | |
| 268 $ delete 'tmp'; | |
| 269 $ return %X10000000 | |
| 270 $ | |
| 271 $! End of filter subroutine. | |
| 272 $ | |
| 273 $endfunc: | |
| 274 $ return | |
| 275 $ | |
| 276 $! EOF |