view src/debugger.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 695b50472e85
children bede81965821
line wrap: on
line source

/* 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.
 */

/*
 * debugger.c: Vim script debugger functions
 */

#include "vim.h"

#if defined(FEAT_EVAL) || defined(PROTO)
static int debug_greedy = FALSE;	// batch mode debugging: don't save
					// and restore typeahead.
static void do_setdebugtracelevel(char_u *arg);
static void do_checkbacktracelevel(void);
static void do_showbacktrace(char_u *cmd);

static char_u *debug_oldval = NULL;	// old and newval for debug expressions
static char_u *debug_newval = NULL;
static int     debug_expr   = 0;	// use debug_expr

    int
has_watchexpr(void)
{
    return debug_expr;
}

/*
 * do_debug(): Debug mode.
 * Repeatedly get Ex commands, until told to continue normal execution.
 */
    void
do_debug(char_u *cmd)
{
    int		save_msg_scroll = msg_scroll;
    int		save_State = State;
    int		save_did_emsg = did_emsg;
    int		save_cmd_silent = cmd_silent;
    int		save_msg_silent = msg_silent;
    int		save_emsg_silent = emsg_silent;
    int		save_redir_off = redir_off;
    tasave_T	typeaheadbuf;
    int		typeahead_saved = FALSE;
    int		save_ignore_script = 0;
    int		save_ex_normal_busy;
    int		n;
    char_u	*cmdline = NULL;
    char_u	*p;
    char_u	*sname;
    char	*tail = NULL;
    static int	last_cmd = 0;
#define CMD_CONT	1
#define CMD_NEXT	2
#define CMD_STEP	3
#define CMD_FINISH	4
#define CMD_QUIT	5
#define CMD_INTERRUPT	6
#define CMD_BACKTRACE	7
#define CMD_FRAME	8
#define CMD_UP		9
#define CMD_DOWN	10

#ifdef ALWAYS_USE_GUI
    // Can't do this when there is no terminal for input/output.
    if (!gui.in_use)
    {
	// Break as soon as possible.
	debug_break_level = 9999;
	return;
    }
#endif

    // Make sure we are in raw mode and start termcap mode.  Might have side
    // effects...
    settmode(TMODE_RAW);
    starttermcap();

    ++RedrawingDisabled;	// don't redisplay the window
    ++no_wait_return;		// don't wait for return
    did_emsg = FALSE;		// don't use error from debugged stuff
    cmd_silent = FALSE;		// display commands
    msg_silent = FALSE;		// display messages
    emsg_silent = FALSE;	// display error messages
    redir_off = TRUE;		// don't redirect debug commands
    save_timeout_for_debugging();   // disable  regexp timeout flag

    State = MODE_NORMAL;
    debug_mode = TRUE;

    if (!debug_did_msg)
	msg(_("Entering Debug mode.  Type \"cont\" to continue."));
    if (debug_oldval != NULL)
    {
	smsg(_("Oldval = \"%s\""), debug_oldval);
	VIM_CLEAR(debug_oldval);
    }
    if (debug_newval != NULL)
    {
	smsg(_("Newval = \"%s\""), debug_newval);
	VIM_CLEAR(debug_newval);
    }
    sname = estack_sfile(ESTACK_NONE);
    if (sname != NULL)
	msg((char *)sname);
    vim_free(sname);
    if (SOURCING_LNUM != 0)
	smsg(_("line %ld: %s"), SOURCING_LNUM, cmd);
    else
	smsg(_("cmd: %s"), cmd);

    // Repeat getting a command and executing it.
    for (;;)
    {
	msg_scroll = TRUE;
	need_wait_return = FALSE;

	// Save the current typeahead buffer and replace it with an empty one.
	// This makes sure we get input from the user here and don't interfere
	// with the commands being executed.  Reset "ex_normal_busy" to avoid
	// the side effects of using ":normal". Save the stuff buffer and make
	// it empty. Set ignore_script to avoid reading from script input.
	save_ex_normal_busy = ex_normal_busy;
	ex_normal_busy = 0;
	if (!debug_greedy)
	{
	    save_typeahead(&typeaheadbuf);
	    typeahead_saved = TRUE;
	    save_ignore_script = ignore_script;
	    ignore_script = TRUE;
	}

	// don't debug any function call, e.g. from an expression mapping
	n = debug_break_level;
	debug_break_level = -1;

	vim_free(cmdline);
	cmdline = getcmdline_prompt('>', NULL, 0, EXPAND_NOTHING, NULL);

	debug_break_level = n;
	if (typeahead_saved)
	{
	    restore_typeahead(&typeaheadbuf, TRUE);
	    ignore_script = save_ignore_script;
	}
	ex_normal_busy = save_ex_normal_busy;

	cmdline_row = msg_row;
	msg_starthere();
	if (cmdline != NULL)
	{
	    // If this is a debug command, set "last_cmd".
	    // If not, reset "last_cmd".
	    // For a blank line use previous command.
	    p = skipwhite(cmdline);
	    if (*p != NUL)
	    {
		switch (*p)
		{
		    case 'c': last_cmd = CMD_CONT;
			      tail = "ont";
			      break;
		    case 'n': last_cmd = CMD_NEXT;
			      tail = "ext";
			      break;
		    case 's': last_cmd = CMD_STEP;
			      tail = "tep";
			      break;
		    case 'f':
			      last_cmd = 0;
			      if (p[1] == 'r')
			      {
				  last_cmd = CMD_FRAME;
				  tail = "rame";
			      }
			      else
			      {
				  last_cmd = CMD_FINISH;
				  tail = "inish";
			      }
			      break;
		    case 'q': last_cmd = CMD_QUIT;
			      tail = "uit";
			      break;
		    case 'i': last_cmd = CMD_INTERRUPT;
			      tail = "nterrupt";
			      break;
		    case 'b': last_cmd = CMD_BACKTRACE;
			      if (p[1] == 't')
				  tail = "t";
			      else
				  tail = "acktrace";
			      break;
		    case 'w': last_cmd = CMD_BACKTRACE;
			      tail = "here";
			      break;
		    case 'u': last_cmd = CMD_UP;
			      tail = "p";
			      break;
		    case 'd': last_cmd = CMD_DOWN;
			      tail = "own";
			      break;
		    default: last_cmd = 0;
		}
		if (last_cmd != 0)
		{
		    // Check that the tail matches.
		    ++p;
		    while (*p != NUL && *p == *tail)
		    {
			++p;
			++tail;
		    }
		    if (ASCII_ISALPHA(*p) && last_cmd != CMD_FRAME)
			last_cmd = 0;
		}
	    }

	    if (last_cmd != 0)
	    {
		// Execute debug command: decide where to break next and
		// return.
		switch (last_cmd)
		{
		    case CMD_CONT:
			debug_break_level = -1;
			break;
		    case CMD_NEXT:
			debug_break_level = ex_nesting_level;
			break;
		    case CMD_STEP:
			debug_break_level = 9999;
			break;
		    case CMD_FINISH:
			debug_break_level = ex_nesting_level - 1;
			break;
		    case CMD_QUIT:
			got_int = TRUE;
			debug_break_level = -1;
			break;
		    case CMD_INTERRUPT:
			got_int = TRUE;
			debug_break_level = 9999;
			// Do not repeat ">interrupt" cmd, continue stepping.
			last_cmd = CMD_STEP;
			break;
		    case CMD_BACKTRACE:
			do_showbacktrace(cmd);
			continue;
		    case CMD_FRAME:
			if (*p == NUL)
			{
			    do_showbacktrace(cmd);
			}
			else
			{
			    p = skipwhite(p);
			    do_setdebugtracelevel(p);
			}
			continue;
		    case CMD_UP:
			debug_backtrace_level++;
			do_checkbacktracelevel();
			continue;
		    case CMD_DOWN:
			debug_backtrace_level--;
			do_checkbacktracelevel();
			continue;
		}
		// Going out reset backtrace_level
		debug_backtrace_level = 0;
		break;
	    }

	    // don't debug this command
	    n = debug_break_level;
	    debug_break_level = -1;
	    (void)do_cmdline(cmdline, getexline, NULL,
						DOCMD_VERBOSE|DOCMD_EXCRESET);
	    debug_break_level = n;
	}
	lines_left = Rows - 1;
    }
    vim_free(cmdline);

    if (RedrawingDisabled > 0)
	--RedrawingDisabled;
    --no_wait_return;
    redraw_all_later(UPD_NOT_VALID);
    need_wait_return = FALSE;
    msg_scroll = save_msg_scroll;
    restore_timeout_for_debugging();
    lines_left = Rows - 1;
    State = save_State;
    debug_mode = FALSE;
    did_emsg = save_did_emsg;
    cmd_silent = save_cmd_silent;
    msg_silent = save_msg_silent;
    emsg_silent = save_emsg_silent;
    redir_off = save_redir_off;

    // Only print the message again when typing a command before coming back
    // here.
    debug_did_msg = TRUE;
}

    static int
get_maxbacktrace_level(char_u *sname)
{
    char	*p, *q;
    int		maxbacktrace = 0;

    if (sname == NULL)
	return 0;

    p = (char *)sname;
    while ((q = strstr(p, "..")) != NULL)
    {
	p = q + 2;
	maxbacktrace++;
    }
    return maxbacktrace;
}

    static void
do_setdebugtracelevel(char_u *arg)
{
    int level;

    level = atoi((char *)arg);
    if (*arg == '+' || level < 0)
	debug_backtrace_level += level;
    else
	debug_backtrace_level = level;

    do_checkbacktracelevel();
}

    static void
do_checkbacktracelevel(void)
{
    if (debug_backtrace_level < 0)
    {
	debug_backtrace_level = 0;
	msg(_("frame is zero"));
    }
    else
    {
	char_u	*sname = estack_sfile(ESTACK_NONE);
	int	max = get_maxbacktrace_level(sname);

	if (debug_backtrace_level > max)
	{
	    debug_backtrace_level = max;
	    smsg(_("frame at highest level: %d"), max);
	}
	vim_free(sname);
    }
}

    static void
do_showbacktrace(char_u *cmd)
{
    char_u  *sname;
    char    *cur;
    char    *next;
    int	    i = 0;
    int	    max;

    sname = estack_sfile(ESTACK_NONE);
    max = get_maxbacktrace_level(sname);
    if (sname != NULL)
    {
	cur = (char *)sname;
	while (!got_int)
	{
	    next = strstr(cur, "..");
	    if (next != NULL)
		*next = NUL;
	    if (i == max - debug_backtrace_level)
		smsg("->%d %s", max - i, cur);
	    else
		smsg("  %d %s", max - i, cur);
	    ++i;
	    if (next == NULL)
		break;
	    *next = '.';
	    cur = next + 2;
	}
	vim_free(sname);
    }

    if (SOURCING_LNUM != 0)
       smsg(_("line %ld: %s"), (long)SOURCING_LNUM, cmd);
    else
       smsg(_("cmd: %s"), cmd);
}

/*
 * ":debug".
 */
    void
ex_debug(exarg_T *eap)
{
    int		debug_break_level_save = debug_break_level;

    debug_break_level = 9999;
    do_cmdline_cmd(eap->arg);
    debug_break_level = debug_break_level_save;
}

static char_u	*debug_breakpoint_name = NULL;
static linenr_T	debug_breakpoint_lnum;

/*
 * When debugging or a breakpoint is set on a skipped command, no debug prompt
 * is shown by do_one_cmd().  This situation is indicated by debug_skipped, and
 * debug_skipped_name is then set to the source name in the breakpoint case.  If
 * a skipped command decides itself that a debug prompt should be displayed, it
 * can do so by calling dbg_check_skipped().
 */
static int	debug_skipped;
static char_u	*debug_skipped_name;

/*
 * Go to debug mode when a breakpoint was encountered or "ex_nesting_level" is
 * at or below the break level.  But only when the line is actually
 * executed.  Return TRUE and set breakpoint_name for skipped commands that
 * decide to execute something themselves.
 * Called from do_one_cmd() before executing a command.
 */
    void
dbg_check_breakpoint(exarg_T *eap)
{
    char_u	*p;

    debug_skipped = FALSE;
    if (debug_breakpoint_name != NULL)
    {
	if (!eap->skip)
	{
	    // replace K_SNR with "<SNR>"
	    if (debug_breakpoint_name[0] == K_SPECIAL
		    && debug_breakpoint_name[1] == KS_EXTRA
		    && debug_breakpoint_name[2] == KE_SNR)
		p = (char_u *)"<SNR>";
	    else
		p = (char_u *)"";
	    smsg(_("Breakpoint in \"%s%s\" line %ld"),
		    p,
		    debug_breakpoint_name + (*p == NUL ? 0 : 3),
		    (long)debug_breakpoint_lnum);
	    debug_breakpoint_name = NULL;
	    do_debug(eap->cmd);
	}
	else
	{
	    debug_skipped = TRUE;
	    debug_skipped_name = debug_breakpoint_name;
	    debug_breakpoint_name = NULL;
	}
    }
    else if (ex_nesting_level <= debug_break_level)
    {
	if (!eap->skip)
	    do_debug(eap->cmd);
	else
	{
	    debug_skipped = TRUE;
	    debug_skipped_name = NULL;
	}
    }
}

/*
 * Go to debug mode if skipped by dbg_check_breakpoint() because eap->skip was
 * set.  Return TRUE when the debug mode is entered this time.
 */
    int
dbg_check_skipped(exarg_T *eap)
{
    int		prev_got_int;

    if (!debug_skipped)
	return FALSE;

    // Save the value of got_int and reset it.  We don't want a previous
    // interruption cause flushing the input buffer.
    prev_got_int = got_int;
    got_int = FALSE;
    debug_breakpoint_name = debug_skipped_name;
    // eap->skip is TRUE
    eap->skip = FALSE;
    (void)dbg_check_breakpoint(eap);
    eap->skip = TRUE;
    got_int |= prev_got_int;
    return TRUE;
}

/*
 * The list of breakpoints: dbg_breakp.
 * This is a grow-array of structs.
 */
struct debuggy
{
    int		dbg_nr;		// breakpoint number
    int		dbg_type;	// DBG_FUNC, DBG_FILE or DBG_EXPR
    char_u	*dbg_name;	// function, expression or file name
    regprog_T	*dbg_prog;	// regexp program
    linenr_T	dbg_lnum;	// line number in function or file
    int		dbg_forceit;	// ! used
#ifdef FEAT_EVAL
    typval_T    *dbg_val;       // last result of watchexpression
#endif
    int		dbg_level;      // stored nested level for expr
};

static garray_T dbg_breakp = {0, 0, sizeof(struct debuggy), 4, NULL};
#define BREAKP(idx)		(((struct debuggy *)dbg_breakp.ga_data)[idx])
#define DEBUGGY(gap, idx)	(((struct debuggy *)gap->ga_data)[idx])
static int last_breakp = 0;	// nr of last defined breakpoint
static int has_expr_breakpoint = FALSE;

#ifdef FEAT_PROFILE
// Profiling uses file and func names similar to breakpoints.
static garray_T prof_ga = {0, 0, sizeof(struct debuggy), 4, NULL};
#endif
#define DBG_FUNC	1
#define DBG_FILE	2
#define DBG_EXPR	3

static linenr_T debuggy_find(int file,char_u *fname, linenr_T after, garray_T *gap, int *fp);

/*
 * Evaluate the "bp->dbg_name" expression and return the result.
 * Disables error messages.
 */
    static typval_T *
eval_expr_no_emsg(struct debuggy *bp)
{
    typval_T	*tv;

    // Disable error messages, a bad expression would make Vim unusable.
    ++emsg_off;
    tv = eval_expr(bp->dbg_name, NULL);
    --emsg_off;

    return tv;
}

/*
 * Parse the arguments of ":profile", ":breakadd" or ":breakdel" and put them
 * in the entry just after the last one in dbg_breakp.  Note that "dbg_name"
 * is allocated.
 * Returns FAIL for failure.
 */
    static int
dbg_parsearg(
    char_u	*arg,
    garray_T	*gap)	    // either &dbg_breakp or &prof_ga
{
    char_u	*p = arg;
    char_u	*q;
    struct debuggy *bp;
    int		here = FALSE;

    if (ga_grow(gap, 1) == FAIL)
	return FAIL;
    bp = &DEBUGGY(gap, gap->ga_len);

    // Find "func" or "file".
    if (STRNCMP(p, "func", 4) == 0)
	bp->dbg_type = DBG_FUNC;
    else if (STRNCMP(p, "file", 4) == 0)
	bp->dbg_type = DBG_FILE;
    else if (
#ifdef FEAT_PROFILE
	    gap != &prof_ga &&
#endif
	    STRNCMP(p, "here", 4) == 0)
    {
	if (curbuf->b_ffname == NULL)
	{
	    emsg(_(e_no_file_name));
	    return FAIL;
	}
	bp->dbg_type = DBG_FILE;
	here = TRUE;
    }
    else if (
#ifdef FEAT_PROFILE
	    gap != &prof_ga &&
#endif
	    STRNCMP(p, "expr", 4) == 0)
	bp->dbg_type = DBG_EXPR;
    else
    {
	semsg(_(e_invalid_argument_str), p);
	return FAIL;
    }
    p = skipwhite(p + 4);

    // Find optional line number.
    if (here)
	bp->dbg_lnum = curwin->w_cursor.lnum;
    else if (
#ifdef FEAT_PROFILE
	    gap != &prof_ga &&
#endif
	    VIM_ISDIGIT(*p))
    {
	bp->dbg_lnum = getdigits(&p);
	p = skipwhite(p);
    }
    else
	bp->dbg_lnum = 0;

    // Find the function or file name.  Don't accept a function name with ().
    if ((!here && *p == NUL)
	    || (here && *p != NUL)
	    || (bp->dbg_type == DBG_FUNC && strstr((char *)p, "()") != NULL))
    {
	semsg(_(e_invalid_argument_str), arg);
	return FAIL;
    }

    if (bp->dbg_type == DBG_FUNC)
	bp->dbg_name = vim_strsave(STRNCMP(p, "g:", 2) == 0 ? p + 2 : p);
    else if (here)
	bp->dbg_name = vim_strsave(curbuf->b_ffname);
    else if (bp->dbg_type == DBG_EXPR)
    {
	bp->dbg_name = vim_strsave(p);
	if (bp->dbg_name != NULL)
	    bp->dbg_val = eval_expr_no_emsg(bp);
    }
    else
    {
	// Expand the file name in the same way as do_source().  This means
	// doing it twice, so that $DIR/file gets expanded when $DIR is
	// "~/dir".
	q = expand_env_save(p);
	if (q == NULL)
	    return FAIL;
	p = expand_env_save(q);
	vim_free(q);
	if (p == NULL)
	    return FAIL;
	if (*p != '*')
	{
	    bp->dbg_name = fix_fname(p);
	    vim_free(p);
	}
	else
	    bp->dbg_name = p;
    }

    if (bp->dbg_name == NULL)
	return FAIL;
    return OK;
}

/*
 * ":breakadd".  Also used for ":profile".
 */
    void
ex_breakadd(exarg_T *eap)
{
    struct debuggy *bp;
    char_u	*pat;
    garray_T	*gap;

    gap = &dbg_breakp;
#ifdef FEAT_PROFILE
    if (eap->cmdidx == CMD_profile)
	gap = &prof_ga;
#endif

    if (dbg_parsearg(eap->arg, gap) != OK)
	return;

    bp = &DEBUGGY(gap, gap->ga_len);
    bp->dbg_forceit = eap->forceit;

    if (bp->dbg_type != DBG_EXPR)
    {
	pat = file_pat_to_reg_pat(bp->dbg_name, NULL, NULL, FALSE);
	if (pat != NULL)
	{
	    bp->dbg_prog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
	    vim_free(pat);
	}
	if (pat == NULL || bp->dbg_prog == NULL)
	    vim_free(bp->dbg_name);
	else
	{
	    if (bp->dbg_lnum == 0)	// default line number is 1
		bp->dbg_lnum = 1;
#ifdef FEAT_PROFILE
	    if (eap->cmdidx != CMD_profile)
#endif
	    {
		DEBUGGY(gap, gap->ga_len).dbg_nr = ++last_breakp;
		++debug_tick;
	    }
	    ++gap->ga_len;
	}
    }
    else
    {
	// DBG_EXPR
	DEBUGGY(gap, gap->ga_len++).dbg_nr = ++last_breakp;
	++debug_tick;
	if (gap == &dbg_breakp)
	    has_expr_breakpoint = TRUE;
    }
}

/*
 * ":debuggreedy".
 */
    void
ex_debuggreedy(exarg_T *eap)
{
    if (eap->addr_count == 0 || eap->line2 != 0)
	debug_greedy = TRUE;
    else
	debug_greedy = FALSE;
}

    static void
update_has_expr_breakpoint(void)
{
    int i;

    has_expr_breakpoint = FALSE;
    for (i = 0; i < dbg_breakp.ga_len; ++i)
	if (BREAKP(i).dbg_type == DBG_EXPR)
	{
	    has_expr_breakpoint = TRUE;
	    break;
	}
}

/*
 * Return TRUE if there is any expression breakpoint.
 */
    int
debug_has_expr_breakpoint(void)
{
    return has_expr_breakpoint;
}

/*
 * ":breakdel" and ":profdel".
 */
    void
ex_breakdel(exarg_T *eap)
{
    struct debuggy *bp, *bpi;
    int		nr;
    int		todel = -1;
    int		del_all = FALSE;
    int		i;
    linenr_T	best_lnum = 0;
    garray_T	*gap;

    gap = &dbg_breakp;
    if (eap->cmdidx == CMD_profdel)
    {
#ifdef FEAT_PROFILE
	gap = &prof_ga;
#else
	ex_ni(eap);
	return;
#endif
    }

    if (vim_isdigit(*eap->arg))
    {
	// ":breakdel {nr}"
	nr = atol((char *)eap->arg);
	for (i = 0; i < gap->ga_len; ++i)
	    if (DEBUGGY(gap, i).dbg_nr == nr)
	    {
		todel = i;
		break;
	    }
    }
    else if (*eap->arg == '*')
    {
	todel = 0;
	del_all = TRUE;
    }
    else
    {
	// ":breakdel {func|file|expr} [lnum] {name}"
	if (dbg_parsearg(eap->arg, gap) == FAIL)
	    return;
	bp = &DEBUGGY(gap, gap->ga_len);
	for (i = 0; i < gap->ga_len; ++i)
	{
	    bpi = &DEBUGGY(gap, i);
	    if (bp->dbg_type == bpi->dbg_type
		    && STRCMP(bp->dbg_name, bpi->dbg_name) == 0
		    && (bp->dbg_lnum == bpi->dbg_lnum
			|| (bp->dbg_lnum == 0
			    && (best_lnum == 0
				|| bpi->dbg_lnum < best_lnum))))
	    {
		todel = i;
		best_lnum = bpi->dbg_lnum;
	    }
	}
	vim_free(bp->dbg_name);
    }

    if (todel < 0)
    {
	semsg(_(e_breakpoint_not_found_str), eap->arg);
	return;
    }

    while (gap->ga_len > 0)
    {
	vim_free(DEBUGGY(gap, todel).dbg_name);
#ifdef FEAT_EVAL
	if (DEBUGGY(gap, todel).dbg_type == DBG_EXPR
		&& DEBUGGY(gap, todel).dbg_val != NULL)
	    free_tv(DEBUGGY(gap, todel).dbg_val);
#endif
	vim_regfree(DEBUGGY(gap, todel).dbg_prog);
	--gap->ga_len;
	if (todel < gap->ga_len)
	    mch_memmove(&DEBUGGY(gap, todel), &DEBUGGY(gap, todel + 1),
		    (gap->ga_len - todel) * sizeof(struct debuggy));
#ifdef FEAT_PROFILE
	if (eap->cmdidx == CMD_breakdel)
#endif
	    ++debug_tick;
	if (!del_all)
	    break;
    }

    // If all breakpoints were removed clear the array.
    if (gap->ga_len == 0)
	ga_clear(gap);
    if (gap == &dbg_breakp)
	update_has_expr_breakpoint();
}

/*
 * ":breaklist".
 */
    void
ex_breaklist(exarg_T *eap UNUSED)
{
    struct debuggy *bp;
    int		i;

    if (dbg_breakp.ga_len == 0)
    {
	msg(_("No breakpoints defined"));
	return;
    }

    for (i = 0; i < dbg_breakp.ga_len; ++i)
    {
	bp = &BREAKP(i);
	if (bp->dbg_type == DBG_FILE)
	    home_replace(NULL, bp->dbg_name, NameBuff, MAXPATHL, TRUE);
	if (bp->dbg_type != DBG_EXPR)
	    smsg(_("%3d  %s %s  line %ld"),
		    bp->dbg_nr,
		    bp->dbg_type == DBG_FUNC ? "func" : "file",
		    bp->dbg_type == DBG_FUNC ? bp->dbg_name : NameBuff,
		    (long)bp->dbg_lnum);
	else
	    smsg(_("%3d  expr %s"),
		    bp->dbg_nr, bp->dbg_name);
    }
}

/*
 * Find a breakpoint for a function or sourced file.
 * Returns line number at which to break; zero when no matching breakpoint.
 */
    linenr_T
dbg_find_breakpoint(
    int		file,	    // TRUE for a file, FALSE for a function
    char_u	*fname,	    // file or function name
    linenr_T	after)	    // after this line number
{
    return debuggy_find(file, fname, after, &dbg_breakp, NULL);
}

#if defined(FEAT_PROFILE) || defined(PROTO)
/*
 * Return TRUE if profiling is on for a function or sourced file.
 */
    int
has_profiling(
    int		file,	    // TRUE for a file, FALSE for a function
    char_u	*fname,	    // file or function name
    int		*fp)	    // return: forceit
{
    return (debuggy_find(file, fname, (linenr_T)0, &prof_ga, fp)
							      != (linenr_T)0);
}
#endif

/*
 * Common code for dbg_find_breakpoint() and has_profiling().
 */
    static linenr_T
debuggy_find(
    int		is_file,    // TRUE for a file, FALSE for a function
    char_u	*fname,	    // file or function name
    linenr_T	after,	    // after this line number
    garray_T	*gap,	    // either &dbg_breakp or &prof_ga
    int		*fp)	    // if not NULL: return forceit
{
    struct debuggy *bp;
    int		i;
    linenr_T	lnum = 0;
    char_u	*name = NULL;
    char_u	*short_name = fname;
    int		prev_got_int;

    // Return quickly when there are no breakpoints.
    if (gap->ga_len == 0)
	return (linenr_T)0;

    // For a script-local function remove the prefix, so that
    // "profile func Func" matches "Func" in any script.  Otherwise it's very
    // difficult to profile/debug a script-local function.  It may match a
    // function in the wrong script, but that is much better than not being
    // able to profile/debug a function in a script with unknown ID.
    // Also match a script-specific name.
    if (!is_file && fname[0] == K_SPECIAL)
    {
	short_name = vim_strchr(fname, '_') + 1;
	name = alloc(STRLEN(fname) + 3);
	if (name != NULL)
	{
	    STRCPY(name, "<SNR>");
	    STRCPY(name + 5, fname + 3);
	}
    }

    for (i = 0; i < gap->ga_len; ++i)
    {
	// Skip entries that are not useful or are for a line that is beyond
	// an already found breakpoint.
	bp = &DEBUGGY(gap, i);
	if (((bp->dbg_type == DBG_FILE) == is_file
		    && bp->dbg_type != DBG_EXPR && (
#ifdef FEAT_PROFILE
		gap == &prof_ga ||
#endif
		(bp->dbg_lnum > after && (lnum == 0 || bp->dbg_lnum < lnum)))))
	{
	    // Save the value of got_int and reset it.  We don't want a
	    // previous interruption cancel matching, only hitting CTRL-C
	    // while matching should abort it.
	    prev_got_int = got_int;
	    got_int = FALSE;
	    if ((name != NULL
		   && vim_regexec_prog(&bp->dbg_prog, FALSE, name, (colnr_T)0))
		    || vim_regexec_prog(&bp->dbg_prog, FALSE,
						       short_name, (colnr_T)0))
	    {
		lnum = bp->dbg_lnum;
		if (fp != NULL)
		    *fp = bp->dbg_forceit;
	    }
	    got_int |= prev_got_int;
	}
#ifdef FEAT_EVAL
	else if (bp->dbg_type == DBG_EXPR)
	{
	    typval_T *tv;
	    int	      line = FALSE;

	    tv = eval_expr_no_emsg(bp);
	    if (tv != NULL)
	    {
		if (bp->dbg_val == NULL)
		{
		    debug_oldval = typval_tostring(NULL, TRUE);
		    bp->dbg_val = tv;
		    debug_newval = typval_tostring(bp->dbg_val, TRUE);
		    line = TRUE;
		}
		else
		{
		    // Use "==" instead of "is" for strings, that is what we
		    // always have done.
		    exprtype_T	type = tv->v_type == VAR_STRING
							? EXPR_EQUAL : EXPR_IS;

		    if (typval_compare(tv, bp->dbg_val, type, FALSE) == OK
			    && tv->vval.v_number == FALSE)
		    {
			typval_T *v;

			line = TRUE;
			debug_oldval = typval_tostring(bp->dbg_val, TRUE);
			// Need to evaluate again, typval_compare() overwrites
			// "tv".
			v = eval_expr_no_emsg(bp);
			debug_newval = typval_tostring(v, TRUE);
			free_tv(bp->dbg_val);
			bp->dbg_val = v;
		    }
		    free_tv(tv);
		}
	    }
	    else if (bp->dbg_val != NULL)
	    {
		debug_oldval = typval_tostring(bp->dbg_val, TRUE);
		debug_newval = typval_tostring(NULL, TRUE);
		free_tv(bp->dbg_val);
		bp->dbg_val = NULL;
		line = TRUE;
	    }

	    if (line)
	    {
		lnum = after > 0 ? after : 1;
		break;
	    }
	}
#endif
    }
    if (name != fname)
	vim_free(name);

    return lnum;
}

/*
 * Called when a breakpoint was encountered.
 */
    void
dbg_breakpoint(char_u *name, linenr_T lnum)
{
    // We need to check if this line is actually executed in do_one_cmd()
    debug_breakpoint_name = name;
    debug_breakpoint_lnum = lnum;
}
#endif