view src/termlib.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 50555279168b
children
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4 noet: */
/*
 * The following software is (C) 1984 Peter da Silva, the Mad Australian, in
 * the public domain. It may be re-distributed for any purpose with the
 * inclusion of this notice.
 */

// Modified by Bram Moolenaar for use with VIM - Vi Improved.
// A few bugs removed by Olaf 'Rhialto' Seibert.

// TERMLIB: Terminal independent database.

#include "vim.h"
#include "termlib.pro"

#if !defined(AMIGA) && !defined(VMS)
# include <sgtty.h>
#endif

static int  getent(char *, char *, FILE *, int);
static int  nextent(char *, FILE *, int);
static int  _match(char *, char *);
static char *_addfmt(char *, char *, int);
static char *_find(char *, char *);

/*
 * Global variables for termlib
 */

char	*tent;		      // Pointer to terminal entry, set by tgetent
char	PC = 0;		      // Pad character, default NULL
char	*UP = 0, *BC = 0;     // Pointers to UP and BC strings from database
short	ospeed;		      // Baud rate (1-16, 1=300, 16=19200), as in stty

/*
 * Module: tgetent
 *
 * Purpose: Get termcap entry for <term> into buffer at <tbuf>.
 *
 * Calling conventions: char tbuf[TBUFSZ+], term=canonical name for terminal.
 *
 * Returned values: 1 = success, -1 = can't open file,
 *	    0 = can't find terminal.
 *
 * Notes:
 * - Should probably supply static buffer.
 * - Uses environment variables "TERM" and "TERMCAP". If TERM = term (that is,
 *   if the argument matches the environment) then it looks at TERMCAP.
 * - If TERMCAP begins with a slash, then it assumes this is the file to
 *   search rather than /etc/termcap.
 * - If TERMCAP does not begin with a slash, and it matches TERM, then this is
 *   used as the entry.
 * - This could be simplified considerably for non-UNIX systems.
 */

#ifndef TERMCAPFILE
# ifdef AMIGA
#  define TERMCAPFILE "s:termcap"
# else
#  ifdef VMS
#   define TERMCAPFILE "VIMRUNTIME:termcap"
#  else
#   define TERMCAPFILE "/etc/termcap"
#  endif
# endif
#endif

    int
tgetent(
    char    *tbuf,		// Buffer to hold termcap entry, TBUFSZ bytes max
    char    *term)		// Name of terminal
{
    char    tcbuf[32];		// Temp buffer to handle
    char    *tcptr = tcbuf;	// extended entries
    char    *tcap = TERMCAPFILE; // Default termcap file
    char    *tmp;
    FILE    *termcap;
    int	    retval = 0;
    int	    len;

    if ((tmp = (char *)mch_getenv((char_u *)"TERMCAP")) != NULL)
    {
	if (*tmp == '/')		// TERMCAP = name of termcap file
	{
	    tcap = tmp ;
#if defined(AMIGA)
	    // Convert /usr/share/lib/termcap to usr:share/lib/termcap
	    tcap++;
	    tmp = strchr(tcap, '/');
	    if (tmp)
		*tmp = ':';
#endif
	}
	else				// TERMCAP = termcap entry itself
	{
	    int tlen = strlen(term);

	    while (*tmp && *tmp != ':')		// Check if TERM matches
	    {
		char *nexttmp;

		while (*tmp == '|')
		    tmp++;
		nexttmp  = _find(tmp, ":|");	// Rhialto
		if (tmp+tlen == nexttmp && _match(tmp, term) == tlen)
		{
		    strcpy(tbuf, tmp);
		    tent = tbuf;
		    return 1;
		}
		else
		    tmp = nexttmp;
	    }
	}
    }
    if (!(termcap = mch_fopen(tcap, "r")))
    {
	strcpy(tbuf, tcap);
	return -1;
    }

    len = 0;
    while (getent(tbuf + len, term, termcap, TBUFSZ - len))
    {
	tcptr = tcbuf;				// Rhialto
	if ((term = tgetstr("tc", &tcptr)))	// extended entry
	{
	    rewind(termcap);
	    len = strlen(tbuf);
	}
	else
	{
	    retval = 1;
	    tent = tbuf;	// reset it back to the beginning
	    break;
	}
    }
    fclose(termcap);
    return retval;
}

    static int
getent(char *tbuf, char *term, FILE *termcap, int buflen)
{
    char    *tptr;
    int	    tlen = strlen(term);

    while (nextent(tbuf, termcap, buflen))	// For each possible entry
    {
	tptr = tbuf;
	while (*tptr && *tptr != ':')		// : terminates name field
	{
	    char    *nexttptr;

	    while (*tptr == '|')		// | separates names
		tptr++;
	    nexttptr = _find(tptr, ":|");	// Rhialto
	    if (tptr + tlen == nexttptr &&
		_match(tptr, term) == tlen)	// FOUND!
	    {
		tent = tbuf;
		return 1;
	    }
	    else				// Look for next name
		tptr = nexttptr;
	}
    }
    return 0;
}

/*
 * Read 1 entry from TERMCAP file.
 */
    static int
nextent(char *tbuf, FILE *termcap, int buflen)
{
    char *lbuf = tbuf;				// lbuf=line buffer
				// read lines straight into buffer

    while (lbuf < tbuf+buflen &&		// There's room and
	  fgets(lbuf, (int)(tbuf+buflen-lbuf), termcap)) // another line
    {
	int llen = strlen(lbuf);

	if (*lbuf == '#')			// eat comments
	    continue;
	if (lbuf[-1] == ':' &&			// and whitespace
	    lbuf[0] == '\t' &&
	    lbuf[1] == ':')
	{
	    STRMOVE(lbuf, lbuf + 2);
	    llen -= 2;
	}
	if (lbuf[llen-2] == '\\')		// and continuations
	    lbuf += llen-2;
	else
	{
	    lbuf[llen-1]=0;			// no continuation, return
	    return 1;
	}
    }

    return 0;					// ran into end of file
}

/*
 * Module: tgetflag
 *
 * Purpose: returns flag true or false as to the existence of a given entry.
 * used with 'bs', 'am', etc...
 *
 * Calling conventions: id is the 2 character capability id.
 *
 * Returned values: 1 for success, 0 for failure.
 */

    int
tgetflag(char *id)
{
    char    buf[256], *ptr = buf;

    return tgetstr(id, &ptr) ? 1 : 0;
}

/*
 * Module: tgetnum
 *
 * Purpose: get numeric value such as 'li' or 'co' from termcap.
 *
 * Calling conventions: id = 2 character id.
 *
 * Returned values: -1 for failure, else numerical value.
 */

    int
tgetnum(char *id)
{
    char *ptr, buf[256];
    ptr = buf;

    if (tgetstr(id, &ptr))
	return atoi(buf);
    else
	return 0;
}

/*
 * Module: tgetstr
 *
 * Purpose: get terminal capability string from database.
 *
 * Calling conventions: id is the two character capability id.
 *	    (*buf) points into a hold buffer for the
 *	    id. the capability is copied into the buffer
 *	    and (*buf) is advanced to point to the next
 *	    free byte in the buffer.
 *
 * Returned values: 0 = no such entry, otherwise returns original
 *	    (*buf) (now a pointer to the string).
 *
 * Notes
 *	It also decodes certain escape sequences in the buffer.
 *  they should be obvious from the code:
 *	\E = escape.
 *	\n, \r, \t, \f, \b match the 'c' escapes.
 *	^x matches control-x (^@...^_).
 *	\nnn matches nnn octal.
 *	\x, where x is anything else, matches x. I differ
 *  from the standard library here, in that I allow ^: to match
 *  :.
 *
 */

    char *
tgetstr(char *id, char **buf)
{
    int		len = strlen(id);
    char	*tmp=tent;
    char	*hold;
    int		i;

    do {
	tmp = _find(tmp, ":");			// For each field
	while (*tmp == ':')			// skip empty fields
	    tmp++;
	if (!*tmp)
	    break;

	if (_match(id, tmp) == len)
	{
	    tmp += len;				// find '=' '@' or '#'
	    if (*tmp == '@')			// :xx@: entry for tc
		return 0;			// deleted entry
	    hold= *buf;
	    while (*++tmp && *tmp != ':')	// not at end of field
		{
		switch(*tmp)
		{
		case '\\':			// Expand escapes here
		    switch(*++tmp)
		    {
		    case 0:			// ignore backslashes
			tmp--;			// at end of entry
			break;			// shouldn't happen
		    case 'e':
		    case 'E':			// ESC
			*(*buf)++ = ESC;
			break;
		    case 'n':			// \n
			*(*buf)++ = '\n';
			break;
		    case 'r':			// \r
			*(*buf)++ = '\r';
			break;
		    case 't':			// \t
			*(*buf)++ = '\t';
			break;
		    case 'b':			// \b
			*(*buf)++ = '\b';
			break;
		    case 'f':			// \f
			*(*buf)++ = '\f';
			break;
		    case '0':			// \nnn
		    case '1':
		    case '2':
		    case '3':
		    case '4':
		    case '5':
		    case '6':
		    case '7':
		    case '8':
		    case '9':
			**buf = 0;
			    // get up to three digits
			for (i = 0; i < 3 && VIM_ISDIGIT(*tmp); ++i)
			    **buf = **buf * 8 + *tmp++ - '0';
			(*buf)++;
			tmp--;
			break;
		    default:			// \x, for all other x
			*(*buf)++= *tmp;
		    }
		    break;
		case '^':			// control characters
		    ++tmp;
		    *(*buf)++ = Ctrl_chr(*tmp);
		    break;
		default:
		    *(*buf)++ = *tmp;
		}
	    }
	    *(*buf)++ = 0;
	    return hold;
	}
    } while (*tmp);

    return 0;
}

/*
 * Module: tgoto
 *
 * Purpose: decode cm cursor motion string.
 *
 * Calling conventions: cm is cursor motion string.  line, col, are the
 * desired destination.
 *
 * Returned values: a string pointing to the decoded string, or "OOPS" if it
 * cannot be decoded.
 *
 * Notes
 *	The accepted escapes are:
 *	%d	 as in printf, 0 origin.
 *	%2, %3   like %02d, %03d in printf.
 *	%.	 like %c
 *	%+x	 adds <x> to value, then %.
 *	%>xy     if value>x, adds y. No output.
 *	%i	 increments line& col, no output.
 *	%r	 reverses order of line&col. No output.
 *	%%	 prints as a single %.
 *	%n	 exclusive or row & col with 0140.
 *	%B	 BCD, no output.
 *	%D	 reverse coding (x-2*(x%16)), no output.
 */

    char *
tgoto(
    char    *cm,				// cm string, from termcap
    int	    col,				// column, x position
    int	    line)				// line, y position
{
    char    gx, gy,				// x, y
	*ptr,					// pointer in 'cm'
	reverse = 0,				// reverse flag
	*bufp,					// pointer in returned string
	addup = 0,				// add upline
	addbak = 0,				// add backup
	c;
    static char buffer[32];

    if (!cm)
	return "OOPS";				// Kludge, but standard

    bufp = buffer;
    ptr = cm;

    while (*ptr)
    {
	if ((c = *ptr++) != '%')		// normal char
	{
	    *bufp++ = c;
	}
	else
	{				// % escape
	    switch(c = *ptr++)
	    {
	    case 'd':				// decimal
		bufp = _addfmt(bufp, "%d", line);
		line = col;
		break;
	    case '2':				// 2 digit decimal
		bufp = _addfmt(bufp, "%02d", line);
		line = col;
		break;
	    case '3':				// 3 digit decimal
		bufp = _addfmt(bufp, "%03d", line);
		line = col;
		break;
	    case '>':				// %>xy: if >x, add y
		gx = *ptr++;
		gy = *ptr++;
		if (col>gx) col += gy;
		if (line>gx) line += gy;
		break;
	    case '+':				// %+c: add c
		line += *ptr++;
	    case '.':				// print x/y
		if (line == '\t' ||		// these are
		   line == '\n' ||		// chars that
		   line == '\004' ||		// UNIX hates
		   line == '\0')
		{
		    line++;			// so go to next pos
		    if (reverse == (line == col))
			addup=1;		// and mark UP
		    else
			addbak=1;		// or BC
		}
		*bufp++=line;
		line = col;
		break;
	    case 'r':				// r: reverse
		gx = line;
		line = col;
		col = gx;
		reverse = 1;
		break;
	    case 'i':			// increment (1-origin screen)
		col++;
		line++;
		break;
	    case '%':				// %%=% literally
		*bufp++='%';
		break;
	    case 'n':				// magic DM2500 code
		line ^= 0140;
		col ^= 0140;
		break;
	    case 'B':				// bcd encoding
		line = line/10<<4+line%10;
		col = col/10<<4+col%10;
		break;
	    case 'D':				// magic Delta Data code
		line = line-2*(line&15);
		col = col-2*(col&15);
		break;
	    default:				// Unknown escape
		return "OOPS";
	    }
	}
    }

    if (addup)					// add upline
	if (UP)
	{
	    ptr=UP;
	    while (VIM_ISDIGIT(*ptr) || *ptr == '.')
		ptr++;
	    if (*ptr == '*')
		ptr++;
	    while (*ptr)
		*bufp++ = *ptr++;
	}

    if (addbak)					// add backspace
	if (BC)
	{
	    ptr=BC;
	    while (VIM_ISDIGIT(*ptr) || *ptr == '.')
		ptr++;
	    if (*ptr == '*')
		ptr++;
	    while (*ptr)
		*bufp++ = *ptr++;
	}
	else
	    *bufp++='\b';

    *bufp = 0;

    return(buffer);
}

/*
 * Module: tputs
 *
 * Purpose: decode padding information
 *
 * Calling conventions: cp = string to be padded, affcnt = # of items affected
 *	(lines, characters, whatever), outc = routine to output 1 character.
 *
 * Returned values: none
 *
 * Notes
 *	cp has padding information ahead of it, in the form
 *  nnnTEXT or nnn*TEXT. nnn is the number of milliseconds to delay,
 *  and may be a decimal (nnn.mmm). If the asterisk is given, then
 *  the delay is multiplied by afcnt. The delay is produced by outputting
 *  a number of nulls (or other padding char) after printing the
 *  TEXT.
 *
 */

long _bauds[16]={
    0,	50, 75,	110,
    134,    150,    200,    300,
    600,    1200,   1800,   2400,
    4800,   9600,   19200,  19200 };

    int
tputs(
    char *cp,				// string to print
    int affcnt,				// Number of lines affected
    void (*outc)(unsigned int))		// routine to output 1 character
{
    long    frac,			// 10^(#digits after decimal point)
	counter,			// digits
	atol(const char *);

    if (VIM_ISDIGIT(*cp))
    {
	counter = 0;
	frac = 1000;
	while (VIM_ISDIGIT(*cp))
	    counter = counter * 10L + (long)(*cp++ - '0');
	if (*cp == '.')
	    while (VIM_ISDIGIT(*++cp))
	    {
		counter = counter * 10L + (long)(*cp++ - '0');
		frac = frac * 10;
	    }
	if (*cp!='*')			// multiply by affected lines
	{
	    if (affcnt>1) affcnt = 1;
	}
	else
	    cp++;

	// Calculate number of characters for padding counter/frac ms delay
	if (ospeed)
	    counter = (counter * _bauds[ospeed] * (long)affcnt) / frac;

	while (*cp)			// output string
	    (*outc)(*cp++);
	if (ospeed)
	    while (counter--)		// followed by pad characters
		(*outc)(PC);
    }
    else
	while (*cp)
	    (*outc)(*cp++);
    return 0;
}

/*
 * Module: tutil.c
 *
 * Purpose: Utility routines for TERMLIB functions.
 * Returns length of text common to s1 and s2.
 */
    static int
_match(char *s1, char *s2)
{
    int i = 0;

    while (s1[i] && s1[i] == s2[i])
	i++;

    return i;
}

/*
 * finds next c in s that's a member of set, returns pointer
 */
    static char *
_find(char *s, char *set)
{
    for (; *s; s++)
    {
	char	*ptr = set;

	while (*ptr && *s != *ptr)
	    ptr++;

	if (*ptr)
	    return s;
    }

    return s;
}

/*
 * add val to buf according to format fmt
 */
    static char *
_addfmt(char *buf, char *fmt, int val)
{
    sprintf(buf, fmt, val);
    while (*buf)
	buf++;
    return buf;
}