text: /* 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.
   */
  
  /*
   * Code to handle tags and the tag stack
   */
  
  #include "vim.h"
  
  /*
   * Structure to hold pointers to various items in a tag line.
   */
  typedef struct tag_pointers
  {
      // filled in by parse_tag_line():
      char_u	*tagname;	// start of tag name (skip "file:")
      char_u	*tagname_end;	// char after tag name
      char_u	*fname;		// first char of file name
      char_u	*fname_end;	// char after file name
      char_u	*command;	// first char of command
      // filled in by parse_match():
      char_u	*command_end;	// first char after command
      char_u	*tag_fname;	// file name of the tags file. This is used
  				// when 'tr' is set.
  #ifdef FEAT_EMACS_TAGS
      int		is_etag;	// TRUE for emacs tag
  #endif
      char_u	*tagkind;	// "kind:" value
      char_u	*tagkind_end;	// end of tagkind
      char_u	*user_data;	// user_data string
      char_u	*user_data_end;	// end of user_data
      linenr_T	tagline;	// "line:" value
  } tagptrs_T;
  
  /*
   * Return values used when reading lines from a tags file.
   */
  typedef enum
  {
      TAGS_READ_SUCCESS = 1,
      TAGS_READ_EOF,
      TAGS_READ_IGNORE,
  } tags_read_status_T;
  
  /*
   * States used during a tags search
   */
  typedef enum
  {
      TS_START,		// at start of file
      TS_LINEAR,		// linear searching forward, till EOF
      TS_BINARY,		// binary searching
      TS_SKIP_BACK,	// skipping backwards
      TS_STEP_FORWARD	// stepping forwards
  } tagsearch_state_T;	// Current search state
  
  /*
   * Binary search file offsets in a tags file
   */
  typedef struct
  {
      off_T	low_offset;	// offset for first char of first line that
  				// could match
      off_T	high_offset;	// offset of char after last line that could
  				// match
      off_T	curr_offset;	// Current file offset in search range
      off_T	curr_offset_used; // curr_offset used when skipping back
      off_T	match_offset;	// Where the binary search found a tag
      int	low_char;		// first char at low_offset
      int	high_char;		// first char at high_offset
  } tagsearch_info_T;
  
  /*
   * Return values used when matching tags against a pattern.
   */
  typedef enum
  {
      TAG_MATCH_SUCCESS = 1,
      TAG_MATCH_FAIL,
      TAG_MATCH_STOP,
      TAG_MATCH_NEXT
  } tagmatch_status_T;
  
  /*
   * Arguments used for matching tags read from a tags file against a pattern.
   */
  typedef struct
  {
      int	matchoff;		// tag match offset
      int	match_re;		// TRUE if the tag matches a regexp
      int	match_no_ic;		// TRUE if the tag matches with case
      int	has_re;			// regular expression used
      int	sortic;			// tags file sorted ignoring case (foldcase)
      int	sort_error;		// tags file not sorted
  } findtags_match_args_T;
  
  /*
   * The matching tags are first stored in one of the hash tables.  In
   * which one depends on the priority of the match.
   * ht_match[] is used to find duplicates, ga_match[] to keep them in sequence.
   * At the end, all the matches from ga_match[] are concatenated, to make a list
   * sorted on priority.
   */
  #define MT_ST_CUR	0		// static match in current file
  #define MT_GL_CUR	1		// global match in current file
  #define MT_GL_OTH	2		// global match in other file
  #define MT_ST_OTH	3		// static match in other file
  #define MT_IC_OFF	4		// add for icase match
  #define MT_RE_OFF	8		// add for regexp match
  #define MT_MASK		7		// mask for printing priority
  #define MT_COUNT	16
  
  static char	*mt_names[MT_COUNT/2] =
  		{"FSC", "F C", "F  ", "FS ", " SC", "  C", "   ", " S "};
  
  #define NOTAGFILE	99		// return value for jumpto_tag
  static char_u	*nofile_fname = NULL;	// fname for NOTAGFILE error
  
  static void taglen_advance(int l);
  
  static int jumpto_tag(char_u *lbuf, int forceit, int keep_help);
  #ifdef FEAT_EMACS_TAGS
  static int parse_tag_line(char_u *lbuf, int is_etag, tagptrs_T *tagp);
  #else
  static int parse_tag_line(char_u *lbuf, tagptrs_T *tagp);
  #endif
  static int test_for_static(tagptrs_T *);
  static int parse_match(char_u *lbuf, tagptrs_T *tagp);
  static char_u *tag_full_fname(tagptrs_T *tagp);
  static char_u *expand_tag_fname(char_u *fname, char_u *tag_fname, int expand);
  #ifdef FEAT_EMACS_TAGS
  static int test_for_current(int, char_u *, char_u *, char_u *, char_u *);
  #else
  static int test_for_current(char_u *, char_u *, char_u *, char_u *);
  #endif
  static int find_extra(char_u **pp);
  static void print_tag_list(int new_tag, int use_tagstack, int num_matches, char_u **matches);
  #if defined(FEAT_QUICKFIX) && defined(FEAT_EVAL)
  static int add_llist_tags(char_u *tag, int num_matches, char_u **matches);
  #endif
  static void tagstack_clear_entry(taggy_T *item);
  
  static char_u	*tagmatchname = NULL;	// name of last used tag
  
  #if defined(FEAT_QUICKFIX)
  /*
   * Tag for preview window is remembered separately, to avoid messing up the
   * normal tagstack.
   */
  static taggy_T ptag_entry = {NULL, {{0, 0, 0}, 0}, 0, 0, NULL};
  #endif
  
  #ifdef FEAT_EVAL
  static int  tfu_in_use = FALSE;	    // disallow recursive call of tagfunc
  static callback_T tfu_cb;	    // 'tagfunc' callback function
  #endif
  
  // Used instead of NUL to separate tag fields in the growarrays.
  #define TAG_SEP 0x02
  
  #if defined(FEAT_EVAL) || defined(PROTO)
  /*
   * Reads the 'tagfunc' option value and convert that to a callback value.
   * Invoked when the 'tagfunc' option is set. The option value can be a name of
   * a function (string), or function(<name>) or funcref(<name>) or a lambda.
   */
      int
  set_tagfunc_option(void)
  {
  #ifdef FEAT_EVAL
      free_callback(&tfu_cb);
      free_callback(&curbuf->b_tfu_cb);
  
      if (*curbuf->b_p_tfu == NUL)
  	return OK;
  
      if (option_set_callback_func(curbuf->b_p_tfu, &tfu_cb) == FAIL)
  	return FAIL;
  
      copy_callback(&curbuf->b_tfu_cb, &tfu_cb);
  #endif
  
      return OK;
  }
  #endif
  
  # if defined(EXITFREE) || defined(PROTO)
      void
  free_tagfunc_option(void)
  {
  # ifdef FEAT_EVAL
      free_callback(&tfu_cb);
  # endif
  }
  # endif
  
  #if defined(FEAT_EVAL) || defined(PROTO)
  /*
   * Mark the global 'tagfunc' callback with 'copyID' so that it is not garbage
   * collected.
   */
      int
  set_ref_in_tagfunc(int copyID UNUSED)
  {
      int	abort = FALSE;
  
      abort = set_ref_in_callback(&tfu_cb, copyID);
  
      return abort;
  }
  
  /*
   * Copy the global 'tagfunc' callback function to the buffer-local 'tagfunc'
   * callback for 'buf'.
   */
      void
  set_buflocal_tfu_callback(buf_T *buf UNUSED)
  {
      free_callback(&buf->b_tfu_cb);
      if (tfu_cb.cb_name != NULL && *tfu_cb.cb_name != NUL)
  	copy_callback(&buf->b_tfu_cb, &tfu_cb);
  }
  #endif
  
  /*
   * Jump to tag; handling of tag commands and tag stack
   *
   * *tag != NUL: ":tag {tag}", jump to new tag, add to tag stack
   *
   * type == DT_TAG:	":tag [tag]", jump to newer position or same tag again
   * type == DT_HELP:	like DT_TAG, but don't use regexp.
   * type == DT_POP:	":pop" or CTRL-T, jump to old position
   * type == DT_NEXT:	jump to next match of same tag
   * type == DT_PREV:	jump to previous match of same tag
   * type == DT_FIRST:	jump to first match of same tag
   * type == DT_LAST:	jump to last match of same tag
   * type == DT_SELECT:	":tselect [tag]", select tag from a list of all matches
   * type == DT_JUMP:	":tjump [tag]", jump to tag or select tag from a list
   * type == DT_CSCOPE:	use cscope to find the tag
   * type == DT_LTAG:	use location list for displaying tag matches
   * type == DT_FREE:	free cached matches
   *
   * for cscope, returns TRUE if we jumped to tag or aborted, FALSE otherwise
   */
      int
  do_tag(
      char_u	*tag,		// tag (pattern) to jump to
      int		type,
      int		count,
      int		forceit,	// :ta with !
      int		verbose)	// print "tag not found" message
  {
      taggy_T	*tagstack = curwin->w_tagstack;
      int		tagstackidx = curwin->w_tagstackidx;
      int		tagstacklen = curwin->w_tagstacklen;
      int		cur_match = 0;
      int		cur_fnum = curbuf->b_fnum;
      int		oldtagstackidx = tagstackidx;
      int		prevtagstackidx = tagstackidx;
      int		prev_num_matches;
      int		new_tag = FALSE;
      int		i;
      int		ic;
      int		no_regexp = FALSE;
      int		error_cur_match = 0;
      int		save_pos = FALSE;
      fmark_T	saved_fmark;
  #ifdef FEAT_CSCOPE
      int		jumped_to_tag = FALSE;
  #endif
      int		new_num_matches;
      char_u	**new_matches;
      int		use_tagstack;
      int		skip_msg = FALSE;
      char_u	*buf_ffname = curbuf->b_ffname;	    // name to use for
  						    // priority computation
      int         use_tfu = 1;
  
      // remember the matches for the last used tag
      static int		num_matches = 0;
      static int		max_num_matches = 0;  // limit used for match search
      static char_u	**matches = NULL;
      static int		flags;
  
  #ifdef FEAT_EVAL
      if (tfu_in_use)
      {
  	emsg(_(e_cannot_modify_tag_stack_within_tagfunc));
  	return FALSE;
      }
  #endif
  
  #ifdef EXITFREE
      if (type == DT_FREE)
      {
  	// remove the list of matches
  	FreeWild(num_matches, matches);
  # ifdef FEAT_CSCOPE
  	cs_free_tags();
  # endif
  	num_matches = 0;
  	return FALSE;
      }
  #endif
  
      if (type == DT_HELP)
      {
  	type = DT_TAG;
  	no_regexp = TRUE;
  	use_tfu = 0;
      }
  
      prev_num_matches = num_matches;
      free_string_option(nofile_fname);
      nofile_fname = NULL;
  
      CLEAR_POS(&saved_fmark.mark);	// shutup gcc 4.0
      saved_fmark.fnum = 0;
  
      /*
       * Don't add a tag to the tagstack if 'tagstack' has been reset.
       */
      if ((!p_tgst && *tag != NUL))
      {
  	use_tagstack = FALSE;
  	new_tag = TRUE;
  #if defined(FEAT_QUICKFIX)
  	if (g_do_tagpreview != 0)
  	{
  	    tagstack_clear_entry(&ptag_entry);
  	    if ((ptag_entry.tagname = vim_strsave(tag)) == NULL)
  		goto end_do_tag;
  	}
  #endif
      }
      else
      {
  #if defined(FEAT_QUICKFIX)
  	if (g_do_tagpreview != 0)
  	    use_tagstack = FALSE;
  	else
  #endif
  	    use_tagstack = TRUE;
  
  	// new pattern, add to the tag stack
  	if (*tag != NUL
  		&& (type == DT_TAG || type == DT_SELECT || type == DT_JUMP
  #ifdef FEAT_QUICKFIX
  		    || type == DT_LTAG
  #endif
  #ifdef FEAT_CSCOPE
  		    || type == DT_CSCOPE
  #endif
  		    ))
  	{
  #if defined(FEAT_QUICKFIX)
  	    if (g_do_tagpreview != 0)
  	    {
  		if (ptag_entry.tagname != NULL
  			&& STRCMP(ptag_entry.tagname, tag) == 0)
  		{
  		    // Jumping to same tag: keep the current match, so that
  		    // the CursorHold autocommand example works.
  		    cur_match = ptag_entry.cur_match;
  		    cur_fnum = ptag_entry.cur_fnum;
  		}
  		else
  		{
  		    tagstack_clear_entry(&ptag_entry);
  		    if ((ptag_entry.tagname = vim_strsave(tag)) == NULL)
  			goto end_do_tag;
  		}
  	    }
  	    else
  #endif
  	    {
  		/*
  		 * If the last used entry is not at the top, delete all tag
  		 * stack entries above it.
  		 */
  		while (tagstackidx < tagstacklen)
  		    tagstack_clear_entry(&tagstack[--tagstacklen]);
  
  		// if the tagstack is full: remove oldest entry
  		if (++tagstacklen > TAGSTACKSIZE)
  		{
  		    tagstacklen = TAGSTACKSIZE;
  		    tagstack_clear_entry(&tagstack[0]);
  		    for (i = 1; i < tagstacklen; ++i)
  			tagstack[i - 1] = tagstack[i];
  		    --tagstackidx;
  		}
  
  		/*
  		 * put the tag name in the tag stack
  		 */
  		if ((tagstack[tagstackidx].tagname = vim_strsave(tag)) == NULL)
  		{
  		    curwin->w_tagstacklen = tagstacklen - 1;
  		    goto end_do_tag;
  		}
  		curwin->w_tagstacklen = tagstacklen;
  
  		save_pos = TRUE;	// save the cursor position below
  	    }
  
  	    new_tag = TRUE;
  	}
  	else
  	{
  	    if (
  #if defined(FEAT_QUICKFIX)
  		    g_do_tagpreview != 0 ? ptag_entry.tagname == NULL :
  #endif
  		    tagstacklen == 0)
  	    {
  		// empty stack
  		emsg(_(e_tag_stack_empty));
  		goto end_do_tag;
  	    }
  
  	    if (type == DT_POP)		// go to older position
  	    {
  #ifdef FEAT_FOLDING
  		int	old_KeyTyped = KeyTyped;
  #endif
  		if ((tagstackidx -= count) < 0)
  		{
  		    emsg(_(e_at_bottom_of_tag_stack));
  		    if (tagstackidx + count == 0)
  		    {
  			// We did [num]^T from the bottom of the stack
  			tagstackidx = 0;
  			goto end_do_tag;
  		    }
  		    // We weren't at the bottom of the stack, so jump all the
  		    // way to the bottom now.
  		    tagstackidx = 0;
  		}
  		else if (tagstackidx >= tagstacklen)    // count == 0?
  		{
  		    emsg(_(e_at_top_of_tag_stack));
  		    goto end_do_tag;
  		}
  
  		// Make a copy of the fmark, autocommands may invalidate the
  		// tagstack before it's used.
  		saved_fmark = tagstack[tagstackidx].fmark;
  		if (saved_fmark.fnum != curbuf->b_fnum)
  		{
  		    /*
  		     * Jump to other file. If this fails (e.g. because the
  		     * file was changed) keep original position in tag stack.
  		     */
  		    if (buflist_getfile(saved_fmark.fnum, saved_fmark.mark.lnum,
  					       GETF_SETMARK, forceit) == FAIL)
  		    {
  			tagstackidx = oldtagstackidx;  // back to old posn
  			goto end_do_tag;
  		    }
  		    // An BufReadPost autocommand may jump to the '" mark, but
  		    // we don't what that here.
  		    curwin->w_cursor.lnum = saved_fmark.mark.lnum;
  		}
  		else
  		{
  		    setpcmark();
  		    curwin->w_cursor.lnum = saved_fmark.mark.lnum;
  		}
  		curwin->w_cursor.col = saved_fmark.mark.col;
  		curwin->w_set_curswant = TRUE;
  		check_cursor();
  #ifdef FEAT_FOLDING
  		if ((fdo_flags & FDO_TAG) && old_KeyTyped)
  		    foldOpenCursor();
  #endif
  
  		// remove the old list of matches
  		FreeWild(num_matches, matches);
  #ifdef FEAT_CSCOPE
  		cs_free_tags();
  #endif
  		num_matches = 0;
  		tag_freematch();
  		goto end_do_tag;
  	    }
  
  	    if (type == DT_TAG
  #if defined(FEAT_QUICKFIX)
  		    || type == DT_LTAG
  #endif
  	       )
  	    {
  #if defined(FEAT_QUICKFIX)
  		if (g_do_tagpreview != 0)
  		{
  		    cur_match = ptag_entry.cur_match;
  		    cur_fnum = ptag_entry.cur_fnum;
  		}
  		else
  #endif
  		{
  		    // ":tag" (no argument): go to newer pattern
  		    save_pos = TRUE;	// save the cursor position below
  		    if ((tagstackidx += count - 1) >= tagstacklen)
  		    {
  			/*
  			 * Beyond the last one, just give an error message and
  			 * go to the last one.  Don't store the cursor
  			 * position.
  			 */
  			tagstackidx = tagstacklen - 1;
  			emsg(_(e_at_top_of_tag_stack));
  			save_pos = FALSE;
  		    }
  		    else if (tagstackidx < 0)	// must have been count == 0
  		    {
  			emsg(_(e_at_bottom_of_tag_stack));
  			tagstackidx = 0;
  			goto end_do_tag;
  		    }
  		    cur_match = tagstack[tagstackidx].cur_match;
  		    cur_fnum = tagstack[tagstackidx].cur_fnum;
  		}
  		new_tag = TRUE;
  	    }
  	    else				// go to other matching tag
  	    {
  		// Save index for when selection is cancelled.
  		prevtagstackidx = tagstackidx;
  
  #if defined(FEAT_QUICKFIX)
  		if (g_do_tagpreview != 0)
  		{
  		    cur_match = ptag_entry.cur_match;
  		    cur_fnum = ptag_entry.cur_fnum;
  		}
  		else
  #endif
  		{
  		    if (--tagstackidx < 0)
  			tagstackidx = 0;
  		    cur_match = tagstack[tagstackidx].cur_match;
  		    cur_fnum = tagstack[tagstackidx].cur_fnum;
  		}
  		switch (type)
  		{
  		    case DT_FIRST: cur_match = count - 1; break;
  		    case DT_SELECT:
  		    case DT_JUMP:
  #ifdef FEAT_CSCOPE
  		    case DT_CSCOPE:
  #endif
  		    case DT_LAST:  cur_match = MAXCOL - 1; break;
  		    case DT_NEXT:  cur_match += count; break;
  		    case DT_PREV:  cur_match -= count; break;
  		}
  		if (cur_match >= MAXCOL)
  		    cur_match = MAXCOL - 1;
  		else if (cur_match < 0)
  		{
  		    emsg(_(e_cannot_go_before_first_matching_tag));
  		    skip_msg = TRUE;
  		    cur_match = 0;
  		    cur_fnum = curbuf->b_fnum;
  		}
  	    }
  	}
  
  #if defined(FEAT_QUICKFIX)
  	if (g_do_tagpreview != 0)
  	{
  	    if (type != DT_SELECT && type != DT_JUMP)
  	    {
  		ptag_entry.cur_match = cur_match;
  		ptag_entry.cur_fnum = cur_fnum;
  	    }
  	}
  	else
  #endif
  	{
  	    /*
  	     * For ":tag [arg]" or ":tselect" remember position before the jump.
  	     */
  	    saved_fmark = tagstack[tagstackidx].fmark;
  	    if (save_pos)
  	    {
  		tagstack[tagstackidx].fmark.mark = curwin->w_cursor;
  		tagstack[tagstackidx].fmark.fnum = curbuf->b_fnum;
  	    }
  
  	    // Curwin will change in the call to jumpto_tag() if ":stag" was
  	    // used or an autocommand jumps to another window; store value of
  	    // tagstackidx now.
  	    curwin->w_tagstackidx = tagstackidx;
  	    if (type != DT_SELECT && type != DT_JUMP)
  	    {
  		curwin->w_tagstack[tagstackidx].cur_match = cur_match;
  		curwin->w_tagstack[tagstackidx].cur_fnum = cur_fnum;
  	    }
  	}
      }
  
      // When not using the current buffer get the name of buffer "cur_fnum".
      // Makes sure that the tag order doesn't change when using a remembered
      // position for "cur_match".
      if (cur_fnum != curbuf->b_fnum)
      {
  	buf_T *buf = buflist_findnr(cur_fnum);
  
  	if (buf != NULL)
  	    buf_ffname = buf->b_ffname;
      }
  
      /*
       * Repeat searching for tags, when a file has not been found.
       */
      for (;;)
      {
  	int	other_name;
  	char_u	*name;
  
  	/*
  	 * When desired match not found yet, try to find it (and others).
  	 */
  	if (use_tagstack)
  	    name = tagstack[tagstackidx].tagname;
  #if defined(FEAT_QUICKFIX)
  	else if (g_do_tagpreview != 0)
  	    name = ptag_entry.tagname;
  #endif
  	else
  	    name = tag;
  	other_name = (tagmatchname == NULL || STRCMP(tagmatchname, name) != 0);
  	if (new_tag
  		|| (cur_match >= num_matches && max_num_matches != MAXCOL)
  		|| other_name)
  	{
  	    if (other_name)
  	    {
  		vim_free(tagmatchname);
  		tagmatchname = vim_strsave(name);
  	    }
  
  	    if (type == DT_SELECT || type == DT_JUMP
  #if defined(FEAT_QUICKFIX)
  		|| type == DT_LTAG
  #endif
  		)
  		cur_match = MAXCOL - 1;
  	    if (type == DT_TAG)
  		max_num_matches = MAXCOL;
  	    else
  		max_num_matches = cur_match + 1;
  
  	    // when the argument starts with '/', use it as a regexp
  	    if (!no_regexp && *name == '/')
  	    {
  		flags = TAG_REGEXP;
  		++name;
  	    }
  	    else
  		flags = TAG_NOIC;
  
  #ifdef FEAT_CSCOPE
  	    if (type == DT_CSCOPE)
  		flags = TAG_CSCOPE;
  #endif
  	    if (verbose)
  		flags |= TAG_VERBOSE;
  
  	    if (!use_tfu)
  		flags |= TAG_NO_TAGFUNC;
  
  	    if (find_tags(name, &new_num_matches, &new_matches, flags,
  					    max_num_matches, buf_ffname) == OK
  		    && new_num_matches < max_num_matches)
  		max_num_matches = MAXCOL; // If less than max_num_matches
  					  // found: all matches found.
  
  	    // If there already were some matches for the same name, move them
  	    // to the start.  Avoids that the order changes when using
  	    // ":tnext" and jumping to another file.
  	    if (!new_tag && !other_name)
  	    {
  		int	    j, k;
  		int	    idx = 0;
  		tagptrs_T   tagp, tagp2;
  
  		// Find the position of each old match in the new list.  Need
  		// to use parse_match() to find the tag line.
  		for (j = 0; j < num_matches; ++j)
  		{
  		    parse_match(matches[j], &tagp);
  		    for (i = idx; i < new_num_matches; ++i)
  		    {
  			parse_match(new_matches[i], &tagp2);
  			if (STRCMP(tagp.tagname, tagp2.tagname) == 0)
  			{
  			    char_u *p = new_matches[i];
  			    for (k = i; k > idx; --k)
  				new_matches[k] = new_matches[k - 1];
  			    new_matches[idx++] = p;
  			    break;
  			}
  		    }
  		}
  	    }
  	    FreeWild(num_matches, matches);
  	    num_matches = new_num_matches;
  	    matches = new_matches;
  	}
  
  	if (num_matches <= 0)
  	{
  	    if (verbose)
  		semsg(_(e_tag_not_found_str), name);
  #if defined(FEAT_QUICKFIX)
  	    g_do_tagpreview = 0;
  #endif
  	}
  	else
  	{
  	    int ask_for_selection = FALSE;
  
  #ifdef FEAT_CSCOPE
  	    if (type == DT_CSCOPE && num_matches > 1)
  	    {
  		cs_print_tags();
  		ask_for_selection = TRUE;
  	    }
  	    else
  #endif
  	    if (type == DT_TAG && *tag != NUL)
  		// If a count is supplied to the ":tag <name>" command, then
  		// jump to count'th matching tag.
  		cur_match = count > 0 ? count - 1 : 0;
  	    else if (type == DT_SELECT || (type == DT_JUMP && num_matches > 1))
  	    {
  		print_tag_list(new_tag, use_tagstack, num_matches, matches);
  		ask_for_selection = TRUE;
  	    }
  #if defined(FEAT_QUICKFIX) && defined(FEAT_EVAL)
  	    else if (type == DT_LTAG)
  	    {
  		if (add_llist_tags(tag, num_matches, matches) == FAIL)
  		    goto end_do_tag;
  		cur_match = 0;		// Jump to the first tag
  	    }
  #endif
  
  	    if (ask_for_selection == TRUE)
  	    {
  		/*
  		 * Ask to select a tag from the list.
  		 */
  		i = prompt_for_number(NULL);
  		if (i <= 0 || i > num_matches || got_int)
  		{
  		    // no valid choice: don't change anything
  		    if (use_tagstack)
  		    {
  			tagstack[tagstackidx].fmark = saved_fmark;
  			tagstackidx = prevtagstackidx;
  		    }
  #ifdef FEAT_CSCOPE
  		    cs_free_tags();
  		    jumped_to_tag = TRUE;
  #endif
  		    break;
  		}
  		cur_match = i - 1;
  	    }
  
  	    if (cur_match >= num_matches)
  	    {
  		// Avoid giving this error when a file wasn't found and we're
  		// looking for a match in another file, which wasn't found.
  		// There will be an emsg("file doesn't exist") below then.
  		if ((type == DT_NEXT || type == DT_FIRST)
  						      && nofile_fname == NULL)
  		{
  		    if (num_matches == 1)
  			emsg(_(e_there_is_only_one_matching_tag));
  		    else
  			emsg(_(e_cannot_go_beyond_last_matching_tag));
  		    skip_msg = TRUE;
  		}
  		cur_match = num_matches - 1;
  	    }
  	    if (use_tagstack)
  	    {
  		tagptrs_T   tagp;
  
  		tagstack[tagstackidx].cur_match = cur_match;
  		tagstack[tagstackidx].cur_fnum = cur_fnum;
  
  		// store user-provided data originating from tagfunc
  		if (use_tfu && parse_match(matches[cur_match], &tagp) == OK
  			&& tagp.user_data)
  		{
  		    VIM_CLEAR(tagstack[tagstackidx].user_data);
  		    tagstack[tagstackidx].user_data = vim_strnsave(
  			  tagp.user_data, tagp.user_data_end - tagp.user_data);
  		}
  
  		++tagstackidx;
  	    }
  #if defined(FEAT_QUICKFIX)
  	    else if (g_do_tagpreview != 0)
  	    {
  		ptag_entry.cur_match = cur_match;
  		ptag_entry.cur_fnum = cur_fnum;
  	    }
  #endif
  
  	    /*
  	     * Only when going to try the next match, report that the previous
  	     * file didn't exist.  Otherwise an emsg() is given below.
  	     */
  	    if (nofile_fname != NULL && error_cur_match != cur_match)
  		smsg(_("File \"%s\" does not exist"), nofile_fname);
  
  
  	    ic = (matches[cur_match][0] & MT_IC_OFF);
  	    if (type != DT_TAG && type != DT_SELECT && type != DT_JUMP
  #ifdef FEAT_CSCOPE
  		&& type != DT_CSCOPE
  #endif
  		&& (num_matches > 1 || ic)
  		&& !skip_msg)
  	    {
  		// Give an indication of the number of matching tags
  		sprintf((char *)IObuff, _("tag %d of %d%s"),
  				cur_match + 1,
  				num_matches,
  				max_num_matches != MAXCOL ? _(" or more") : "");
  		if (ic)
  		    STRCAT(IObuff, _("  Using tag with different case!"));
  		if ((num_matches > prev_num_matches || new_tag)
  							   && num_matches > 1)
  		{
  		    if (ic)
  			msg_attr((char *)IObuff, HL_ATTR(HLF_W));
  		    else
  			msg((char *)IObuff);
  		    msg_scroll = TRUE;	// don't overwrite this message
  		}
  		else
  		    give_warning(IObuff, ic);
  		if (ic && !msg_scrolled && msg_silent == 0)
  		{
  		    out_flush();
  		    ui_delay(1007L, TRUE);
  		}
  	    }
  
  #if defined(FEAT_EVAL)
  	    // Let the SwapExists event know what tag we are jumping to.
  	    vim_snprintf((char *)IObuff, IOSIZE, ":ta %s\r", name);
  	    set_vim_var_string(VV_SWAPCOMMAND, IObuff, -1);
  #endif
  
  	    /*
  	     * Jump to the desired match.
  	     */
  	    i = jumpto_tag(matches[cur_match], forceit, type != DT_CSCOPE);
  
  #if defined(FEAT_EVAL)
  	    set_vim_var_string(VV_SWAPCOMMAND, NULL, -1);
  #endif
  
  	    if (i == NOTAGFILE)
  	    {
  		// File not found: try again with another matching tag
  		if ((type == DT_PREV && cur_match > 0)
  			|| ((type == DT_TAG || type == DT_NEXT
  							  || type == DT_FIRST)
  			    && (max_num_matches != MAXCOL
  					     || cur_match < num_matches - 1)))
  		{
  		    error_cur_match = cur_match;
  		    if (use_tagstack)
  			--tagstackidx;
  		    if (type == DT_PREV)
  			--cur_match;
  		    else
  		    {
  			type = DT_NEXT;
  			++cur_match;
  		    }
  		    continue;
  		}
  		semsg(_(e_file_str_does_not_exist), nofile_fname);
  	    }
  	    else
  	    {
  		// We may have jumped to another window, check that
  		// tagstackidx is still valid.
  		if (use_tagstack && tagstackidx > curwin->w_tagstacklen)
  		    tagstackidx = curwin->w_tagstackidx;
  #ifdef FEAT_CSCOPE
  		jumped_to_tag = TRUE;
  #endif
  	    }
  	}
  	break;
      }
  
  end_do_tag:
      // Only store the new index when using the tagstack and it's valid.
      if (use_tagstack && tagstackidx <= curwin->w_tagstacklen)
  	curwin->w_tagstackidx = tagstackidx;
      postponed_split = 0;	// don't split next time
  # ifdef FEAT_QUICKFIX
      g_do_tagpreview = 0;	// don't do tag preview next time
  # endif
  
  #ifdef FEAT_CSCOPE
      return jumped_to_tag;
  #else
      return FALSE;
  #endif
  }
  
  /*
   * List all the matching tags.
   */
      static void
  print_tag_list(
      int		new_tag,
      int		use_tagstack,
      int		num_matches,
      char_u	**matches)
  {
      taggy_T	*tagstack = curwin->w_tagstack;
      int		tagstackidx = curwin->w_tagstackidx;
      int		i;
      char_u	*p;
      char_u	*command_end;
      tagptrs_T	tagp;
      int		taglen;
      int		attr;
  
      /*
       * Assume that the first match indicates how long the tags can
       * be, and align the file names to that.
       */
      parse_match(matches[0], &tagp);
      taglen = (int)(tagp.tagname_end - tagp.tagname + 2);
      if (taglen < 18)
  	taglen = 18;
      if (taglen > Columns - 25)
  	taglen = MAXCOL;
      if (msg_col == 0)
  	msg_didout = FALSE;	// overwrite previous message
      msg_start();
      msg_puts_attr(_("  # pri kind tag"), HL_ATTR(HLF_T));
      msg_clr_eos();
      taglen_advance(taglen);
      msg_puts_attr(_("file\n"), HL_ATTR(HLF_T));
  
      for (i = 0; i < num_matches && !got_int; ++i)
      {
  	parse_match(matches[i], &tagp);
  	if (!new_tag && (
  #if defined(FEAT_QUICKFIX)
  		    (g_do_tagpreview != 0
  		     && i == ptag_entry.cur_match) ||
  #endif
  		    (use_tagstack
  		     && i == tagstack[tagstackidx].cur_match)))
  	    *IObuff = '>';
  	else
  	    *IObuff = ' ';
  	vim_snprintf((char *)IObuff + 1, IOSIZE - 1,
  		"%2d %s ", i + 1,
  			       mt_names[matches[i][0] & MT_MASK]);
  	msg_puts((char *)IObuff);
  	if (tagp.tagkind != NULL)
  	    msg_outtrans_len(tagp.tagkind,
  			  (int)(tagp.tagkind_end - tagp.tagkind));
  	msg_advance(13);
  	msg_outtrans_len_attr(tagp.tagname,
  			   (int)(tagp.tagname_end - tagp.tagname),
  						  HL_ATTR(HLF_T));
  	msg_putchar(' ');
  	taglen_advance(taglen);
  
  	// Find out the actual file name. If it is long, truncate
  	// it and put "..." in the middle
  	p = tag_full_fname(&tagp);
  	if (p != NULL)
  	{
  	    msg_outtrans_long_attr(p, HL_ATTR(HLF_D));
  	    vim_free(p);
  	}
  	if (msg_col > 0)
  	    msg_putchar('\n');
  	if (got_int)
  	    break;
  	msg_advance(15);
  
  	// print any extra fields
  	command_end = tagp.command_end;
  	if (command_end != NULL)
  	{
  	    p = command_end + 3;
  	    while (*p && *p != '\r' && *p != '\n')
  	    {
  		while (*p == TAB)
  		    ++p;
  
  		// skip "file:" without a value (static tag)
  		if (STRNCMP(p, "file:", 5) == 0
  					     && vim_isspace(p[5]))
  		{
  		    p += 5;
  		    continue;
  		}
  		// skip "kind:<kind>" and "<kind>"
  		if (p == tagp.tagkind
  			|| (p + 5 == tagp.tagkind
  				&& STRNCMP(p, "kind:", 5) == 0))
  		{
  		    p = tagp.tagkind_end;
  		    continue;
  		}
  		// print all other extra fields
  		attr = HL_ATTR(HLF_CM);
  		while (*p && *p != '\r' && *p != '\n')
  		{
  		    if (msg_col + ptr2cells(p) >= Columns)
  		    {
  			msg_putchar('\n');
  			if (got_int)
  			    break;
  			msg_advance(15);
  		    }
  		    p = msg_outtrans_one(p, attr);
  		    if (*p == TAB)
  		    {
  			msg_puts_attr(" ", attr);
  			break;
  		    }
  		    if (*p == ':')
  			attr = 0;
  		}
  	    }
  	    if (msg_col > 15)
  	    {
  		msg_putchar('\n');
  		if (got_int)
  		    break;
  		msg_advance(15);
  	    }
  	}
  	else
  	{
  	    for (p = tagp.command;
  			      *p && *p != '\r' && *p != '\n'; ++p)
  		;
  	    command_end = p;
  	}
  
  	// Put the info (in several lines) at column 15.
  	// Don't display "/^" and "?^".
  	p = tagp.command;
  	if (*p == '/' || *p == '?')
  	{
  	    ++p;
  	    if (*p == '^')
  		++p;
  	}
  	// Remove leading whitespace from pattern
  	while (p != command_end && vim_isspace(*p))
  	    ++p;
  
  	while (p != command_end)
  	{
  	    if (msg_col + (*p == TAB ? 1 : ptr2cells(p)) > Columns)
  		msg_putchar('\n');
  	    if (got_int)
  		break;
  	    msg_advance(15);
  
  	    // skip backslash used for escaping a command char or
  	    // a backslash
  	    if (*p == '\\' && (*(p + 1) == *tagp.command
  			    || *(p + 1) == '\\'))
  		++p;
  
  	    if (*p == TAB)
  	    {
  		msg_putchar(' ');
  		++p;
  	    }
  	    else
  		p = msg_outtrans_one(p, 0);
  
  	    // don't display the "$/;\"" and "$?;\""
  	    if (p == command_end - 2 && *p == '$'
  				     && *(p + 1) == *tagp.command)
  		break;
  	    // don't display matching '/' or '?'
  	    if (p == command_end - 1 && *p == *tagp.command
  				     && (*p == '/' || *p == '?'))
  		break;
  	}
  	if (msg_col)
  	    msg_putchar('\n');
  	ui_breakcheck();
      }
      if (got_int)
  	got_int = FALSE;	// only stop the listing
  }
  
  #if defined(FEAT_QUICKFIX) && defined(FEAT_EVAL)
  /*
   * Add the matching tags to the location list for the current
   * window.
   */
      static int
  add_llist_tags(
      char_u	*tag,
      int		num_matches,
      char_u	**matches)
  {
      list_T	*list;
      char_u	tag_name[128 + 1];
      char_u	*fname;
      char_u	*cmd;
      int		i;
      char_u	*p;
      tagptrs_T	tagp;
  
      fname = alloc(MAXPATHL + 1);
      cmd = alloc(CMDBUFFSIZE + 1);
      list = list_alloc();
      if (list == NULL || fname == NULL || cmd == NULL)
      {
  	vim_free(cmd);
  	vim_free(fname);
  	if (list != NULL)
  	    list_free(list);
  	return FAIL;
      }
  
      for (i = 0; i < num_matches; ++i)
      {
  	int	    len, cmd_len;
  	long    lnum;
  	dict_T  *dict;
  
  	parse_match(matches[i], &tagp);
  
  	// Save the tag name
  	len = (int)(tagp.tagname_end - tagp.tagname);
  	if (len > 128)
  	    len = 128;
  	vim_strncpy(tag_name, tagp.tagname, len);
  	tag_name[len] = NUL;
  
  	// Save the tag file name
  	p = tag_full_fname(&tagp);
  	if (p == NULL)
  	    continue;
  	vim_strncpy(fname, p, MAXPATHL);
  	vim_free(p);
  
  	// Get the line number or the search pattern used to locate
  	// the tag.
  	lnum = 0;
  	if (isdigit(*tagp.command))
  	    // Line number is used to locate the tag
  	    lnum = atol((char *)tagp.command);
  	else
  	{
  	    char_u *cmd_start, *cmd_end;
  
  	    // Search pattern is used to locate the tag
  
  	    // Locate the end of the command
  	    cmd_start = tagp.command;
  	    cmd_end = tagp.command_end;
  	    if (cmd_end == NULL)
  	    {
  		for (p = tagp.command;
  		     *p && *p != '\r' && *p != '\n'; ++p)
  		    ;
  		cmd_end = p;
  	    }
  
  	    // Now, cmd_end points to the character after the
  	    // command. Adjust it to point to the last
  	    // character of the command.
  	    cmd_end--;
  
  	    // Skip the '/' and '?' characters at the
  	    // beginning and end of the search pattern.
  	    if (*cmd_start == '/' || *cmd_start == '?')
  		cmd_start++;
  
  	    if (*cmd_end == '/' || *cmd_end == '?')
  		cmd_end--;
  
  	    len = 0;
  	    cmd[0] = NUL;
  
  	    // If "^" is present in the tag search pattern, then
  	    // copy it first.
  	    if (*cmd_start == '^')
  	    {
  		STRCPY(cmd, "^");
  		cmd_start++;
  		len++;
  	    }
  
  	    // Precede the tag pattern with \V to make it very
  	    // nomagic.
  	    STRCAT(cmd, "\\V");
  	    len += 2;
  
  	    cmd_len = (int)(cmd_end - cmd_start + 1);
  	    if (cmd_len > (CMDBUFFSIZE - 5))
  		cmd_len = CMDBUFFSIZE - 5;
  	    STRNCAT(cmd, cmd_start, cmd_len);
  	    len += cmd_len;
  
  	    if (cmd[len - 1] == '$')
  	    {
  		// Replace '$' at the end of the search pattern
  		// with '\$'
  		cmd[len - 1] = '\\';
  		cmd[len] = '$';
  		len++;
  	    }
  
  	    cmd[len] = NUL;
  	}
  
  	if ((dict = dict_alloc()) == NULL)
  	    continue;
  	if (list_append_dict(list, dict) == FAIL)
  	{
  	    vim_free(dict);
  	    continue;
  	}
  
  	dict_add_string(dict, "text", tag_name);
  	dict_add_string(dict, "filename", fname);
  	dict_add_number(dict, "lnum", lnum);
  	if (lnum == 0)
  	    dict_add_string(dict, "pattern", cmd);
      }
  
      vim_snprintf((char *)IObuff, IOSIZE, "ltag %s", tag);
      set_errorlist(curwin, list, ' ', IObuff, NULL);
  
      list_free(list);
      vim_free(fname);
      vim_free(cmd);
  
      return OK;
  }
  #endif
  
  /*
   * Free cached tags.
   */
      void
  tag_freematch(void)
  {
      VIM_CLEAR(tagmatchname);
  }
  
      static void
  taglen_advance(int l)
  {
      if (l == MAXCOL)
      {
  	msg_putchar('\n');
  	msg_advance(24);
      }
      else
  	msg_advance(13 + l);
  }
  
  /*
   * Print the tag stack
   */
      void
  do_tags(exarg_T *eap UNUSED)
  {
      int		i;
      char_u	*name;
      taggy_T	*tagstack = curwin->w_tagstack;
      int		tagstackidx = curwin->w_tagstackidx;
      int		tagstacklen = curwin->w_tagstacklen;
  
      // Highlight title
      msg_puts_title(_("\n  # TO tag         FROM line  in file/text"));
      for (i = 0; i < tagstacklen; ++i)
      {
  	if (tagstack[i].tagname != NULL)
  	{
  	    name = fm_getname(&(tagstack[i].fmark), 30);
  	    if (name == NULL)	    // file name not available
  		continue;
  
  	    msg_putchar('\n');
  	    vim_snprintf((char *)IObuff, IOSIZE, "%c%2d %2d %-15s %5ld  ",
  		i == tagstackidx ? '>' : ' ',
  		i + 1,
  		tagstack[i].cur_match + 1,
  		tagstack[i].tagname,
  		tagstack[i].fmark.mark.lnum);
  	    msg_outtrans(IObuff);
  	    msg_outtrans_attr(name, tagstack[i].fmark.fnum == curbuf->b_fnum
  							? HL_ATTR(HLF_D) : 0);
  	    vim_free(name);
  	}
  	out_flush();		    // show one line at a time
      }
      if (tagstackidx == tagstacklen)	// idx at top of stack
  	msg_puts("\n>");
  }
  
  /*
   * Compare two strings, for length "len", ignoring case the ASCII way.
   * return 0 for match, < 0 for smaller, > 0 for bigger
   * Make sure case is folded to uppercase in comparison (like for 'sort -f')
   */
      static int
  tag_strnicmp(char_u *s1, char_u *s2, size_t len)
  {
      int		i;
  
      while (len > 0)
      {
  	i = (int)TOUPPER_ASC(*s1) - (int)TOUPPER_ASC(*s2);
  	if (i != 0)
  	    return i;			// this character different
  	if (*s1 == NUL)
  	    break;			// strings match until NUL
  	++s1;
  	++s2;
  	--len;
      }
      return 0;				// strings match
  }
  
  /*
   * Structure to hold info about the tag pattern being used.
   */
  typedef struct
  {
      char_u	*pat;		// the pattern
      int		len;		// length of pat[]
      char_u	*head;		// start of pattern head
      int		headlen;	// length of head[]
      regmatch_T	regmatch;	// regexp program, may be NULL
  } pat_T;
  
  /*
   * Extract info from the tag search pattern "pats->pat".
   */
      static void
  prepare_pats(pat_T *pats, int has_re)
  {
      pats->head = pats->pat;
      pats->headlen = pats->len;
      if (has_re)
      {
  	// When the pattern starts with '^' or "\\<", binary searching can be
  	// used (much faster).
  	if (pats->pat[0] == '^')
  	    pats->head = pats->pat + 1;
  	else if (pats->pat[0] == '\\' && pats->pat[1] == '<')
  	    pats->head = pats->pat + 2;
  	if (pats->head == pats->pat)
  	    pats->headlen = 0;
  	else
  	    for (pats->headlen = 0; pats->head[pats->headlen] != NUL;
  							      ++pats->headlen)
  		if (vim_strchr((char_u *)(magic_isset() ? ".[~*\\$" : "\\$"),
  					   pats->head[pats->headlen]) != NULL)
  		    break;
  	if (p_tl != 0 && pats->headlen > p_tl)	// adjust for 'taglength'
  	    pats->headlen = p_tl;
      }
  
      if (has_re)
  	pats->regmatch.regprog = vim_regcomp(pats->pat,
  						 magic_isset() ? RE_MAGIC : 0);
      else
  	pats->regmatch.regprog = NULL;
  }
  
  #ifdef FEAT_EVAL
  /*
   * Call the user-defined function to generate a list of tags used by
   * find_tags().
   *
   * Return OK if at least 1 tag has been successfully found,
   * NOTDONE if the function returns v:null, and FAIL otherwise.
   */
      static int
  find_tagfunc_tags(
      char_u	*pat,		// pattern supplied to the user-defined function
      garray_T	*ga,		// the tags will be placed here
      int		*match_count,	// here the number of tags found will be placed
      int		flags,		// flags from find_tags (TAG_*)
      char_u	*buf_ffname)	// name of buffer for priority
  {
      pos_T       save_pos;
      list_T      *taglist;
      listitem_T  *item;
      int         ntags = 0;
      int         result = FAIL;
      typval_T	args[4];
      typval_T	rettv;
      char_u      flagString[4];
      dict_T	*d;
      taggy_T	*tag = &curwin->w_tagstack[curwin->w_tagstackidx];
  
      if (*curbuf->b_p_tfu == NUL || curbuf->b_tfu_cb.cb_name == NULL
  					   || *curbuf->b_tfu_cb.cb_name == NUL)
  	return FAIL;
  
      args[0].v_type = VAR_STRING;
      args[0].vval.v_string = pat;
      args[1].v_type = VAR_STRING;
      args[1].vval.v_string = flagString;
  
      // create 'info' dict argument
      if ((d = dict_alloc_lock(VAR_FIXED)) == NULL)
  	return FAIL;
      if (tag->user_data != NULL)
  	dict_add_string(d, "user_data", tag->user_data);
      if (buf_ffname != NULL)
  	dict_add_string(d, "buf_ffname", buf_ffname);
  
      ++d->dv_refcount;
      args[2].v_type = VAR_DICT;
      args[2].vval.v_dict = d;
  
      args[3].v_type = VAR_UNKNOWN;
  
      vim_snprintf((char *)flagString, sizeof(flagString),
  		 "%s%s%s",
  		 g_tag_at_cursor      ? "c": "",
  		 flags & TAG_INS_COMP ? "i": "",
  		 flags & TAG_REGEXP   ? "r": "");
  
      save_pos = curwin->w_cursor;
      result = call_callback(&curbuf->b_tfu_cb, 0, &rettv, 3, args);
      curwin->w_cursor = save_pos;	// restore the cursor position
      --d->dv_refcount;
  
      if (result == FAIL)
  	return FAIL;
      if (rettv.v_type == VAR_SPECIAL && rettv.vval.v_number == VVAL_NULL)
      {
  	clear_tv(&rettv);
  	return NOTDONE;
      }
      if (rettv.v_type != VAR_LIST || !rettv.vval.v_list)
      {
  	clear_tv(&rettv);
  	emsg(_(e_invalid_return_value_from_tagfunc));
  	return FAIL;
      }
      taglist = rettv.vval.v_list;
  
      FOR_ALL_LIST_ITEMS(taglist, item)
      {
  	char_u		*mfp;
  	char_u		*res_name, *res_fname, *res_cmd, *res_kind;
  	int		len;
  	dict_iterator_T	iter;
  	char_u		*dict_key;
  	typval_T	*tv;
  	int		has_extra = 0;
  	int		name_only = flags & TAG_NAMES;
  
  	if (item->li_tv.v_type != VAR_DICT)
  	{
  	    emsg(_(e_invalid_return_value_from_tagfunc));
  	    break;
  	}
  
  #ifdef FEAT_EMACS_TAGS
  	len = 3;
  #else
  	len = 2;
  #endif
  	res_name = NULL;
  	res_fname = NULL;
  	res_cmd = NULL;
  	res_kind = NULL;
  
  	dict_iterate_start(&item->li_tv, &iter);
  	while (NULL != (dict_key = dict_iterate_next(&iter, &tv)))
  	{
  	    if (tv->v_type != VAR_STRING || tv->vval.v_string == NULL)
  		continue;
  
  	    len += (int)STRLEN(tv->vval.v_string) + 1;   // Space for "\tVALUE"
  	    if (!STRCMP(dict_key, "name"))
  	    {
  		res_name = tv->vval.v_string;
  		continue;
  	    }
  	    if (!STRCMP(dict_key, "filename"))
  	    {
  		res_fname = tv->vval.v_string;
  		continue;
  	    }
  	    if (!STRCMP(dict_key, "cmd"))
  	    {
  		res_cmd = tv->vval.v_string;
  		continue;
  	    }
  	    has_extra = 1;
  	    if (!STRCMP(dict_key, "kind"))
  	    {
  		res_kind = tv->vval.v_string;
  		continue;
  	    }
  	    // Other elements will be stored as "\tKEY:VALUE"
  	    // Allocate space for the key and the colon
  	    len += (int)STRLEN(dict_key) + 1;
  	}
  
  	if (has_extra)
  	    len += 2;	// need space for ;"
  
  	if (!res_name || !res_fname || !res_cmd)
  	{
  	    emsg(_(e_invalid_return_value_from_tagfunc));
  	    break;
  	}
  
  	if (name_only)
  	    mfp = vim_strsave(res_name);
  	else
  	    mfp = alloc(sizeof(char_u) + len + 1);
  
  	if (mfp == NULL)
  	    continue;
  
  	if (!name_only)
  	{
  	    char_u *p = mfp;
  
  	    *p++ = MT_GL_OTH + 1;   // mtt
  	    *p++ = TAG_SEP;	    // no tag file name
  #ifdef FEAT_EMACS_TAGS
  	    *p++ = TAG_SEP;
  #endif
  
  	    STRCPY(p, res_name);
  	    p += STRLEN(p);
  
  	    *p++ = TAB;
  	    STRCPY(p, res_fname);
  	    p += STRLEN(p);
  
  	    *p++ = TAB;
  	    STRCPY(p, res_cmd);
  	    p += STRLEN(p);
  
  	    if (has_extra)
  	    {
  		STRCPY(p, ";\"");
  		p += STRLEN(p);
  
  		if (res_kind)
  		{
  		    *p++ = TAB;
  		    STRCPY(p, res_kind);
  		    p += STRLEN(p);
  		}
  
  		dict_iterate_start(&item->li_tv, &iter);
  		while (NULL != (dict_key = dict_iterate_next(&iter, &tv)))
  		{
  		    if (tv->v_type != VAR_STRING || tv->vval.v_string == NULL)
  			continue;
  
  		    if (!STRCMP(dict_key, "name"))
  			continue;
  		    if (!STRCMP(dict_key, "filename"))
  			continue;
  		    if (!STRCMP(dict_key, "cmd"))
  			continue;
  		    if (!STRCMP(dict_key, "kind"))
  			continue;
  
  		    *p++ = TAB;
  		    STRCPY(p, dict_key);
  		    p += STRLEN(p);
  		    STRCPY(p, ":");
  		    p += STRLEN(p);
  		    STRCPY(p, tv->vval.v_string);
  		    p += STRLEN(p);
  		}
  	    }
  	}
  
  	// Add all matches because tagfunc should do filtering.
  	if (ga_grow(ga, 1) == OK)
  	{
  	    ((char_u **)(ga->ga_data))[ga->ga_len++] = mfp;
  	    ++ntags;
  	    result = OK;
  	}
  	else
  	{
  	    vim_free(mfp);
  	    break;
  	}
      }
  
      clear_tv(&rettv);
  
      *match_count = ntags;
      return result;
  }
  #endif
  
  /*
   * State information used during a tag search
   */
  typedef struct
  {
      tagsearch_state_T	state;		// tag search state
      int		stop_searching;		// stop when match found or error
      pat_T	*orgpat;		// holds unconverted pattern info
      char_u     *lbuf;			// line buffer
      int		lbuf_size;		// length of lbuf
      char_u	*tag_fname;		// name of the tag file
      FILE	*fp;			// current tags file pointer
      int		flags;			// flags used for tag search
      int		tag_file_sorted;	// !_TAG_FILE_SORTED value
      int		get_searchpat;		// used for 'showfulltag'
      int		help_only;		// only search for help tags
      int		did_open;		// did open a tag file
      int		mincount;		// MAXCOL: find all matches
  					// other: minimal number of matches
      int		linear;			// do a linear search
      vimconv_T	vimconv;
  #ifdef FEAT_EMACS_TAGS
      int		is_etag;		// current file is emacs style
      char_u	*ebuf;			// additional buffer for etag fname
  #endif
  #ifdef FEAT_MULTI_LANG
      char_u	help_lang[3];		// lang of current tags file
      int		help_pri;		// help language priority
      char_u	*help_lang_find;	// lang to be found
      int		is_txt;			// flag of file extension
  #endif
      int		match_count;		// number of matches found
      garray_T	ga_match[MT_COUNT];	// stores matches in sequence
      hashtab_T	ht_match[MT_COUNT];	// stores matches by key
  } findtags_state_T;
  
  /*
   * Initialize the state used by find_tags().
   * Returns OK on success and FAIL on memory allocation failure.
   */
      static int
  findtags_state_init(
      findtags_state_T	*st,
      char_u		*pat,
      int			flags,
      int			mincount)
  {
      int		mtt;
  
      st->tag_fname = alloc(MAXPATHL + 1);
      st->fp = NULL;
      st->orgpat = ALLOC_ONE(pat_T);
      st->orgpat->pat = pat;
      st->orgpat->len = (int)STRLEN(pat);
      st->orgpat->regmatch.regprog = NULL;
      st->flags = flags;
      st->tag_file_sorted = NUL;
      st->help_only = (flags & TAG_HELP);
      st->get_searchpat = FALSE;
  #ifdef FEAT_MULTI_LANG
      st->help_lang[0] = NUL;
      st->help_pri = 0;
      st->help_lang_find = NULL;
      st->is_txt = FALSE;
  #endif
      st->did_open = FALSE;
      st->mincount = mincount;
      st->lbuf_size = LSIZE;
      st->lbuf = alloc(st->lbuf_size);
  #ifdef FEAT_EMACS_TAGS
      st->ebuf = alloc(LSIZE);
  #endif
      st->match_count = 0;
      st->stop_searching = FALSE;
  
      for (mtt = 0; mtt < MT_COUNT; ++mtt)
      {
  	ga_init2(&st->ga_match[mtt], sizeof(char_u *), 100);
  	hash_init(&st->ht_match[mtt]);
      }
  
      // check for out of memory situation
      if (st->tag_fname == NULL
  	    || st->lbuf == NULL
  #ifdef FEAT_EMACS_TAGS
  	    || st->ebuf == NULL
  #endif
         )
  	return FAIL;
  
      return OK;
  }
  
  /*
   * Free the state used by find_tags()
   */
      static void
  findtags_state_free(findtags_state_T *st)
  {
      vim_free(st->tag_fname);
      vim_free(st->lbuf);
      vim_regfree(st->orgpat->regmatch.regprog);
      vim_free(st->orgpat);
  #ifdef FEAT_EMACS_TAGS
      vim_free(st->ebuf);
  #endif
  }
  
  #ifdef FEAT_MULTI_LANG
  /*
   * Initialize the language and priority used for searching tags in a Vim help
   * file.
   * Returns TRUE to process the help file for tags and FALSE to skip the file.
   */
      static int
  findtags_in_help_init(findtags_state_T *st)
  {
      int		i;
      char_u	*s;
  
      // Keep 'en' as the language if the file extension is '.txt'
      if (st->is_txt)
  	STRCPY(st->help_lang, "en");
      else
      {
  	// Prefer help tags according to 'helplang'.  Put the two-letter
  	// language name in help_lang[].
  	i = (int)STRLEN(st->tag_fname);
  	if (i > 3 && st->tag_fname[i - 3] == '-')
  	    vim_strncpy(st->help_lang, st->tag_fname + i - 2, 2);
  	else
  	    STRCPY(st->help_lang, "en");
      }
      // When searching for a specific language skip tags files for other
      // languages.
      if (st->help_lang_find != NULL
  	    && STRICMP(st->help_lang, st->help_lang_find) != 0)
  	return FALSE;
  
      // For CTRL-] in a help file prefer a match with the same language.
      if ((st->flags & TAG_KEEP_LANG)
  	    && st->help_lang_find == NULL
  	    && curbuf->b_fname != NULL
  	    && (i = (int)STRLEN(curbuf->b_fname)) > 4
  	    && curbuf->b_fname[i - 1] == 'x'
  	    && curbuf->b_fname[i - 4] == '.'
  	    && STRNICMP(curbuf->b_fname + i - 3, st->help_lang, 2) == 0)
  	st->help_pri = 0;
      else
      {
  	// search for the language in 'helplang'
  	st->help_pri = 1;
  	for (s = p_hlg; *s != NUL; ++s)
  	{
  	    if (STRNICMP(s, st->help_lang, 2) == 0)
  		break;
  	    ++st->help_pri;
  	    if ((s = vim_strchr(s, ',')) == NULL)
  		break;
  	}
  	if (s == NULL || *s == NUL)
  	{
  	    // Language not in 'helplang': use last, prefer English, unless
  	    // found already.
  	    ++st->help_pri;
  	    if (STRICMP(st->help_lang, "en") != 0)
  		++st->help_pri;
  	}
      }
  
      return TRUE;
  }
  #endif
  
  #ifdef FEAT_EVAL
  /*
   * Use the function set in 'tagfunc' (if configured and enabled) to get the
   * tags.
   * Return OK if at least 1 tag has been successfully found, NOTDONE if the
   * 'tagfunc' is not used or the 'tagfunc' returns v:null and FAIL otherwise.
   */
      static int
  findtags_apply_tfu(findtags_state_T *st, char_u *pat, char_u *buf_ffname)
  {
      int         use_tfu = ((st->flags & TAG_NO_TAGFUNC) == 0);
      int		retval;
  
      if (!use_tfu || tfu_in_use || *curbuf->b_p_tfu == NUL)
  	return NOTDONE;
  
      tfu_in_use = TRUE;
      retval = find_tagfunc_tags(pat, st->ga_match, &st->match_count,
  						st->flags, buf_ffname);
      tfu_in_use = FALSE;
  
      return retval;
  }
  #endif
  
  #ifdef FEAT_EMACS_TAGS
  /*
   * Stack for included emacs-tags file.
   * It has a fixed size, to truncate cyclic includes. jw
   */
  # define INCSTACK_SIZE 42
  static struct
  {
      FILE	*fp;
      char_u	*etag_fname;
  } incstack[INCSTACK_SIZE];
  static int incstack_idx = 0;	// index in incstack
  
  /*
   * Free the emacs include tags file stack.
   */
      static void
  emacs_tags_incstack_free(void)
  {
      while (incstack_idx)
      {
  	--incstack_idx;
  	fclose(incstack[incstack_idx].fp);
  	incstack[incstack_idx].fp = NULL;
  	VIM_CLEAR(incstack[incstack_idx].etag_fname);
      }
  }
  
  /*
   * Emacs tags line with CTRL-L: New file name on next line.
   * The file name is followed by a ','.  Remember etag file name in ebuf.
   * The FILE pointer to the tags file is stored in 'st->fp'.  If another tags
   * file is included, then the FILE pointer to the new tags file is stored in
   * 'st->fp'. The old file pointer is saved in incstack.
   */
      static void
  emacs_tags_new_filename(findtags_state_T *st)
  {
      char_u	*p;
      char_u	*fullpath_ebuf;
  
      if (vim_fgets(st->ebuf, LSIZE, st->fp))
  	return;
  
      for (p = st->ebuf; *p && *p != ','; p++)
  	;
      *p = NUL;
  
      // check for an included tags file.
      // atoi(p+1) is the number of bytes before the next ^L unless it is an
      // include statement. Skip the included tags file if it exceeds the
      // maximum.
      if (STRNCMP(p + 1, "include", 7) != 0 || incstack_idx >= INCSTACK_SIZE)
  	return;
  
      // Save current "fp" and "tag_fname" in the stack.
      incstack[incstack_idx].etag_fname = vim_strsave(st->tag_fname);
      if (incstack[incstack_idx].etag_fname == NULL)
  	return;
  
      incstack[incstack_idx].fp = st->fp;
      st->fp = NULL;
  
      // Figure out "tag_fname" and "fp" to use for
      // included file.
      fullpath_ebuf = expand_tag_fname(st->ebuf, st->tag_fname, FALSE);
      if (fullpath_ebuf != NULL)
      {
  	st->fp = mch_fopen((char *)fullpath_ebuf, "r");
  	if (st->fp != NULL)
  	{
  	    if (STRLEN(fullpath_ebuf) > LSIZE)
  		semsg(_(e_tag_file_path_truncated_for_str), st->ebuf);
  	    vim_strncpy(st->tag_fname, fullpath_ebuf, MAXPATHL);
  	    ++incstack_idx;
  	    st->is_etag = FALSE; // we can include anything
  	}
  	vim_free(fullpath_ebuf);
      }
      if (st->fp == NULL)
      {
  	// Can't open the included file, skip it and
  	// restore old value of "fp".
  	st->fp = incstack[incstack_idx].fp;
  	vim_free(incstack[incstack_idx].etag_fname);
      }
  }
  
  /*
   * Reached the end of an emacs-style tags file. If this is an included tags
   * file, then pop it from the incstack and continue processing the parent tags
   * file. Otherwise, processed all the tags.
   * Returns TRUE if an included tags file is popped and processing should
   * continue with the parent tags file. Returns FALSE to stop processing tags.
   */
      static int
  emacs_tags_file_eof(findtags_state_T *st)
  {
      if (!incstack_idx)	// reached end of file. stop processing.
  	return FALSE;
  
      // reached the end of an included tags file. pop it.
      --incstack_idx;
      fclose(st->fp);	// end of this file ...
      st->fp = incstack[incstack_idx].fp;
      STRCPY(st->tag_fname, incstack[incstack_idx].etag_fname);
      vim_free(incstack[incstack_idx].etag_fname);
      st->is_etag = TRUE;	// (only etags can include)
  
      return TRUE;
  }
  
  /*
   * Parse a line from an emacs-style tags file.
   * Returns OK if the line is parsed successfully, returns FAIL if the line is
   * not terminated by a newline.
   */
      static int
  emacs_tags_parse_line(char_u *lbuf, tagptrs_T *tagp)
  {
      char_u	*p_7f;
      char_u	*p;
  
      // There are two formats for an emacs tag line:
      // 1:  struct EnvBase ^?EnvBase^A139,4627
      // 2: #define	ARPB_WILD_WORLD ^?153,5194
      p_7f = vim_strchr(lbuf, 0x7f);
      if (p_7f == NULL)
      {
  etag_fail:
  	if (vim_strchr(lbuf, '\n') != NULL)
  	    return FAIL;
  
  	// Truncated line.  Ignore it.
  	if (p_verbose >= 5)
  	{
  	    verbose_enter();
  	    msg(_("Ignoring long line in tags file"));
  	    verbose_leave();
  	}
  	tagp->command = lbuf;
  	tagp->tagname = lbuf;
  	tagp->tagname_end = lbuf;
  	return OK;
      }
  
      // Find ^A.  If not found the line number is after the 0x7f
      p = vim_strchr(p_7f, Ctrl_A);
      if (p == NULL)
  	p = p_7f + 1;
      else
  	++p;
  
      if (!VIM_ISDIGIT(*p))	    // check for start of line number
  	goto etag_fail;
      tagp->command = p;
  
      if (p[-1] == Ctrl_A)	    // first format: explicit tagname given
      {
  	tagp->tagname = p_7f + 1;
  	tagp->tagname_end = p - 1;
      }
      else			    // second format: isolate tagname
      {
  	// find end of tagname
  	for (p = p_7f - 1; !vim_iswordc(*p); --p)
  	    if (p == lbuf)
  		goto etag_fail;
  	tagp->tagname_end = p + 1;
  	while (p >= lbuf && vim_iswordc(*p))
  	    --p;
  	tagp->tagname = p + 1;
      }
  
      return OK;
  }
  #endif
  
  /*
   * Read the next line from a tags file.
   * Returns TAGS_READ_SUCCESS if a tags line is successfully read and should be
   * processed.
   * Returns TAGS_READ_EOF if the end of file is reached.
   * Returns TAGS_READ_IGNORE if the current line should be ignored (used when
   * reached end of a emacs included tags file)
   */
      static tags_read_status_T
  findtags_get_next_line(findtags_state_T *st, tagsearch_info_T *sinfo_p)
  {
      int		eof;
      off_T	offset;
  
      // For binary search: compute the next offset to use.
      if (st->state == TS_BINARY)
      {
  	offset = sinfo_p->low_offset + ((sinfo_p->high_offset
  						- sinfo_p->low_offset) / 2);
  	if (offset == sinfo_p->curr_offset)
  	    return TAGS_READ_EOF; // End the binary search without a match.
  	else
  	    sinfo_p->curr_offset = offset;
      }
  
      // Skipping back (after a match during binary search).
      else if (st->state == TS_SKIP_BACK)
      {
  	sinfo_p->curr_offset -= st->lbuf_size * 2;
  	if (sinfo_p->curr_offset < 0)
  	{
  	    sinfo_p->curr_offset = 0;
  	    rewind(st->fp);
  	    st->state = TS_STEP_FORWARD;
  	}
      }
  
      // When jumping around in the file, first read a line to find the
      // start of the next line.
      if (st->state == TS_BINARY || st->state == TS_SKIP_BACK)
      {
  	// Adjust the search file offset to the correct position
  	sinfo_p->curr_offset_used = sinfo_p->curr_offset;
  	vim_ignored = vim_fseek(st->fp, sinfo_p->curr_offset, SEEK_SET);
  	eof = vim_fgets(st->lbuf, st->lbuf_size, st->fp);
  	if (!eof && sinfo_p->curr_offset != 0)
  	{
  	    sinfo_p->curr_offset = vim_ftell(st->fp);
  	    if (sinfo_p->curr_offset == sinfo_p->high_offset)
  	    {
  		// oops, gone a bit too far; try from low offset
  		vim_ignored = vim_fseek(st->fp, sinfo_p->low_offset, SEEK_SET);
  		sinfo_p->curr_offset = sinfo_p->low_offset;
  	    }
  	    eof = vim_fgets(st->lbuf, st->lbuf_size, st->fp);
  	}
  	// skip empty and blank lines
  	while (!eof && vim_isblankline(st->lbuf))
  	{
  	    sinfo_p->curr_offset = vim_ftell(st->fp);
  	    eof = vim_fgets(st->lbuf, st->lbuf_size, st->fp);
  	}
  	if (eof)
  	{
  	    // Hit end of file.  Skip backwards.
  	    st->state = TS_SKIP_BACK;
  	    sinfo_p->match_offset = vim_ftell(st->fp);
  	    sinfo_p->curr_offset = sinfo_p->curr_offset_used;
  	    return TAGS_READ_IGNORE;
  	}
      }
      // Not jumping around in the file: Read the next line.
      else
      {
  	// skip empty and blank lines
  	do
  	{
  #ifdef FEAT_CSCOPE
  	    if (st->flags & TAG_CSCOPE)
  		eof = cs_fgets(st->lbuf, st->lbuf_size);
  	    else
  #endif
  		eof = vim_fgets(st->lbuf, st->lbuf_size, st->fp);
  	} while (!eof && vim_isblankline(st->lbuf));
  
  	if (eof)
  	{
  #ifdef FEAT_EMACS_TAGS
  	    if (emacs_tags_file_eof(st) == TRUE)
  		// an included tags file. Continue processing the parent
  		// tags file.
  		return TAGS_READ_IGNORE;
  #endif
  	    return TAGS_READ_EOF;
  	}
      }
  
      return TAGS_READ_SUCCESS;
  }
  
  /*
   * Parse a tags file header line in 'st->lbuf'.
   * Returns TRUE if the current line in st->lbuf is not a tags header line and
   * should be parsed as a regular tag line. Returns FALSE if the line is a
   * header line and the next header line should be read.
   */
      static int
  findtags_hdr_parse(findtags_state_T *st)
  {
      char_u	*p;
  
      // Header lines in a tags file start with "!_TAG_"
      if (STRNCMP(st->lbuf, "!_TAG_", 6) != 0)
  	// Non-header item before the header, e.g. "!" itself.
  	return TRUE;
  
      // Process the header line.
      if (STRNCMP(st->lbuf, "!_TAG_FILE_SORTED\t", 18) == 0)
  	st->tag_file_sorted = st->lbuf[18];
      if (STRNCMP(st->lbuf, "!_TAG_FILE_ENCODING\t", 20) == 0)
      {
  	// Prepare to convert every line from the specified encoding to
  	// 'encoding'.
  	for (p = st->lbuf + 20; *p > ' ' && *p < 127; ++p)
  	    ;
  	*p = NUL;
  	convert_setup(&st->vimconv, st->lbuf + 20, p_enc);
      }
  
      // Read the next line.  Unrecognized flags are ignored.
      return FALSE;
  }
  
  /*
   * Handler to initialize the state when starting to process a new tags file.
   * Called in the TS_START state when finding tags from a tags file.
   * Returns TRUE if the line read from the tags file should be parsed and
   * FALSE if the line should be ignored.
   */
      static int
  findtags_start_state_handler(
      findtags_state_T	*st,
      int			*sortic,
      tagsearch_info_T	*sinfo_p)
  {
  #ifdef FEAT_CSCOPE
      int		use_cscope = (st->flags & TAG_CSCOPE);
  #endif
      int		noic = (st->flags & TAG_NOIC);
      off_T	filesize;
  
      // The header ends when the line sorts below "!_TAG_".  When case is
      // folded lower case letters sort before "_".
      if (STRNCMP(st->lbuf, "!_TAG_", 6) <= 0
  	    || (st->lbuf[0] == '!' && ASCII_ISLOWER(st->lbuf[1])))
  	return findtags_hdr_parse(st);
  
      // Headers ends.
  
      // When there is no tag head, or ignoring case, need to do a
      // linear search.
      // When no "!_TAG_" is found, default to binary search.  If
      // the tag file isn't sorted, the second loop will find it.
      // When "!_TAG_FILE_SORTED" found: start binary search if
      // flag set.
      // For cscope, it's always linear.
  # ifdef FEAT_CSCOPE
      if (st->linear || use_cscope)
  # else
      if (st->linear)
  # endif
  	st->state = TS_LINEAR;
      else if (st->tag_file_sorted == NUL)
  	st->state = TS_BINARY;
      else if (st->tag_file_sorted == '1')
  	st->state = TS_BINARY;
      else if (st->tag_file_sorted == '2')
      {
  	st->state = TS_BINARY;
  	*sortic = TRUE;
  	st->orgpat->regmatch.rm_ic = (p_ic || !noic);
      }
      else
  	st->state = TS_LINEAR;
  
      if (st->state == TS_BINARY && st->orgpat->regmatch.rm_ic && !*sortic)
      {
  	// Binary search won't work for ignoring case, use linear
  	// search.
  	st->linear = TRUE;
  	st->state = TS_LINEAR;
      }
  
      // When starting a binary search, get the size of the file and
      // compute the first offset.
      if (st->state == TS_BINARY)
      {
  	if (vim_fseek(st->fp, 0L, SEEK_END) != 0)
  	    // can't seek, don't use binary search
  	    st->state = TS_LINEAR;
  	else
  	{
  	    // Get the tag file size (don't use mch_fstat(), it's
  	    // not portable).  Don't use lseek(), it doesn't work
  	    // properly on MacOS Catalina.
  	    filesize = vim_ftell(st->fp);
  	    vim_ignored = vim_fseek(st->fp, 0L, SEEK_SET);
  
  	    // Calculate the first read offset in the file.  Start
  	    // the search in the middle of the file.
  	    sinfo_p->low_offset = 0;
  	    sinfo_p->low_char = 0;
  	    sinfo_p->high_offset = filesize;
  	    sinfo_p->curr_offset = 0;
  	    sinfo_p->high_char = 0xff;
  	}
  	return FALSE;
      }
  
      return TRUE;
  }
  
  /*
   * Parse a tag line read from a tags file.
   * Returns OK if a tags line is successfully parsed.
   * Returns FAIL if a format error is encountered.
   */
      static int
  findtags_parse_line(
      findtags_state_T		*st,
      tagptrs_T			*tagpp,
      findtags_match_args_T	*margs,
      tagsearch_info_T		*sinfo_p)
  {
      int		status;
      int		i;
      int		cmplen;
      int		tagcmp;
  
      // Figure out where the different strings are in this line.
      // For "normal" tags: Do a quick check if the tag matches.
      // This speeds up tag searching a lot!
      if (st->orgpat->headlen
  #ifdef FEAT_EMACS_TAGS
  	    && !st->is_etag
  #endif
         )
      {
  	CLEAR_FIELD(*tagpp);
  	tagpp->tagname = st->lbuf;
  	tagpp->tagname_end = vim_strchr(st->lbuf, TAB);
  	if (tagpp->tagname_end == NULL)
  	    // Corrupted tag line.
  	    return TAG_MATCH_FAIL;
  
  	// Skip this line if the length of the tag is different and
  	// there is no regexp, or the tag is too short.
  	cmplen = (int)(tagpp->tagname_end - tagpp->tagname);
  	if (p_tl != 0 && cmplen > p_tl)	    // adjust for 'taglength'
  	    cmplen = p_tl;
  	if ((st->flags & TAG_REGEXP) && st->orgpat->headlen < cmplen)
  	    cmplen = st->orgpat->headlen;
  	else if (st->state == TS_LINEAR && st->orgpat->headlen != cmplen)
  	    return TAG_MATCH_NEXT;
  
  	if (st->state == TS_BINARY)
  	{
  	    // Simplistic check for unsorted tags file.
  	    i = (int)tagpp->tagname[0];
  	    if (margs->sortic)
  		i = (int)TOUPPER_ASC(tagpp->tagname[0]);
  	    if (i < sinfo_p->low_char || i > sinfo_p->high_char)
  		margs->sort_error = TRUE;
  
  	    // Compare the current tag with the searched tag.
  	    if (margs->sortic)
  		tagcmp = tag_strnicmp(tagpp->tagname, st->orgpat->head,
  							(size_t)cmplen);
  	    else
  		tagcmp = STRNCMP(tagpp->tagname, st->orgpat->head, cmplen);
  
  	    // A match with a shorter tag means to search forward.
  	    // A match with a longer tag means to search backward.
  	    if (tagcmp == 0)
  	    {
  		if (cmplen < st->orgpat->headlen)
  		    tagcmp = -1;
  		else if (cmplen > st->orgpat->headlen)
  		    tagcmp = 1;
  	    }
  
  	    if (tagcmp == 0)
  	    {
  		// We've located the tag, now skip back and search
  		// forward until the first matching tag is found.
  		st->state = TS_SKIP_BACK;
  		sinfo_p->match_offset = sinfo_p->curr_offset;
  		return TAG_MATCH_NEXT;
  	    }
  	    if (tagcmp < 0)
  	    {
  		sinfo_p->curr_offset = vim_ftell(st->fp);
  		if (sinfo_p->curr_offset < sinfo_p->high_offset)
  		{
  		    sinfo_p->low_offset = sinfo_p->curr_offset;
  		    if (margs->sortic)
  			sinfo_p->low_char = TOUPPER_ASC(tagpp->tagname[0]);
  		    else
  			sinfo_p->low_char = tagpp->tagname[0];
  		    return TAG_MATCH_NEXT;
  		}
  	    }
  	    if (tagcmp > 0 && sinfo_p->curr_offset != sinfo_p->high_offset)
  	    {
  		sinfo_p->high_offset = sinfo_p->curr_offset;
  		if (margs->sortic)
  		    sinfo_p->high_char = TOUPPER_ASC(tagpp->tagname[0]);
  		else
  		    sinfo_p->high_char = tagpp->tagname[0];
  		return TAG_MATCH_NEXT;
  	    }
  
  	    // No match yet and are at the end of the binary search.
  	    return TAG_MATCH_STOP;
  	}
  	else if (st->state == TS_SKIP_BACK)
  	{
  	    if (MB_STRNICMP(tagpp->tagname, st->orgpat->head, cmplen) != 0)
  		st->state = TS_STEP_FORWARD;
  	    else
  		// Have to skip back more.  Restore the curr_offset
  		// used, otherwise we get stuck at a long line.
  		sinfo_p->curr_offset = sinfo_p->curr_offset_used;
  	    return TAG_MATCH_NEXT;
  	}
  	else if (st->state == TS_STEP_FORWARD)
  	{
  	    if (MB_STRNICMP(tagpp->tagname, st->orgpat->head, cmplen) != 0)
  	    {
  		if ((off_T)vim_ftell(st->fp) > sinfo_p->match_offset)
  		    return TAG_MATCH_STOP;	// past last match
  		else
  		    return TAG_MATCH_NEXT;	// before first match
  	    }
  	}
  	else
  	    // skip this match if it can't match
  	    if (MB_STRNICMP(tagpp->tagname, st->orgpat->head, cmplen) != 0)
  		return TAG_MATCH_NEXT;
  
  	// Can be a matching tag, isolate the file name and command.
  	tagpp->fname = tagpp->tagname_end + 1;
  	tagpp->fname_end = vim_strchr(tagpp->fname, TAB);
  	if (tagpp->fname_end == NULL)
  	    status = FAIL;
  	else
  	{
  	    tagpp->command = tagpp->fname_end + 1;
  	    status = OK;
  	}
      }
      else
  	status = parse_tag_line(st->lbuf,
  #ifdef FEAT_EMACS_TAGS
  		st->is_etag,
  #endif
  		tagpp);
  
      if (status == FAIL)
  	return TAG_MATCH_FAIL;
  
  #ifdef FEAT_EMACS_TAGS
      if (st->is_etag)
  	tagpp->fname = st->ebuf;
  #endif
  
      return TAG_MATCH_SUCCESS;
  }
  
  /*
   * Initialize the structure used for tag matching.
   */
      static void
  findtags_matchargs_init(findtags_match_args_T *margs, int flags)
  {
      margs->matchoff = 0;			// match offset
      margs->match_re = FALSE;			// match with regexp
      margs->match_no_ic = FALSE;			// matches with case
      margs->has_re = (flags & TAG_REGEXP);	// regexp used
      margs->sortic = FALSE;			// tag file sorted in nocase
      margs->sort_error = FALSE;			// tags file not sorted
  }
  
  /*
   * Compares the tag name in 'tagpp->tagname' with a search pattern in
   * 'st->orgpat.head'.
   * Returns TAG_MATCH_SUCCESS if the tag matches, TAG_MATCH_FAIL if the tag
   * doesn't match, TAG_MATCH_NEXT to look for the next matching tag (used in a
   * binary search) and TAG_MATCH_STOP if all the tags are processed without a
   * match. Uses the values in 'margs' for doing the comparison.
   */
      static tagmatch_status_T
  findtags_match_tag(
      findtags_state_T	*st,
      tagptrs_T		*tagpp,
      findtags_match_args_T *margs)
  {
      int		match = FALSE;
      int		cmplen;
  
      // First try matching with the pattern literally (also when it is
      // a regexp).
      cmplen = (int)(tagpp->tagname_end - tagpp->tagname);
      if (p_tl != 0 && cmplen > p_tl)	    // adjust for 'taglength'
  	cmplen = p_tl;
      // if tag length does not match, don't try comparing
      if (st->orgpat->len != cmplen)
  	match = FALSE;
      else
      {
  	if (st->orgpat->regmatch.rm_ic)
  	{
  	    match =
  		(MB_STRNICMP(tagpp->tagname, st->orgpat->pat, cmplen) == 0);
  	    if (match)
  		margs->match_no_ic =
  		    (STRNCMP(tagpp->tagname, st->orgpat->pat, cmplen) == 0);
  	}
  	else
  	    match = (STRNCMP(tagpp->tagname, st->orgpat->pat, cmplen) == 0);
      }
  
      // Has a regexp: Also find tags matching regexp.
      margs->match_re = FALSE;
      if (!match && st->orgpat->regmatch.regprog != NULL)
      {
  	int	cc;
  
  	cc = *tagpp->tagname_end;
  	*tagpp->tagname_end = NUL;
  	match = vim_regexec(&st->orgpat->regmatch, tagpp->tagname, (colnr_T)0);
  	if (match)
  	{
  	    margs->matchoff = (int)(st->orgpat->regmatch.startp[0] -
  							tagpp->tagname);
  	    if (st->orgpat->regmatch.rm_ic)
  	    {
  		st->orgpat->regmatch.rm_ic = FALSE;
  		margs->match_no_ic = vim_regexec(&st->orgpat->regmatch,
  			tagpp->tagname, (colnr_T)0);
  		st->orgpat->regmatch.rm_ic = TRUE;
  	    }
  	}
  	*tagpp->tagname_end = cc;
  	margs->match_re = TRUE;
      }
  
      return match ? TAG_MATCH_SUCCESS : TAG_MATCH_FAIL;
  }
  
  /*
   * Convert the encoding of a line read from a tags file in 'st->lbuf'.
   * Converting the pattern from 'enc' to the tags file encoding doesn't work,
   * because characters are not recognized. The converted line is saved in
   * st->lbuf.
   */
      static void
  findtags_string_convert(findtags_state_T *st)
  {
      char_u	*conv_line;
      int		len;
  
      conv_line = string_convert(&st->vimconv, st->lbuf, NULL);
      if (conv_line == NULL)
  	return;
  
      // Copy or swap lbuf and conv_line.
      len = (int)STRLEN(conv_line) + 1;
      if (len > st->lbuf_size)
      {
  	vim_free(st->lbuf);
  	st->lbuf = conv_line;
  	st->lbuf_size = len;
      }
      else
      {
  	STRCPY(st->lbuf, conv_line);
  	vim_free(conv_line);
      }
  }
  
  /*
   * Add a matching tag found in a tags file to st->ht_match and st->ga_match.
   * Returns OK if successfully added the match and FAIL on memory allocation
   * failure.
   */
      static int
  findtags_add_match(
      findtags_state_T	*st,
      tagptrs_T		*tagpp,
      findtags_match_args_T   *margs,
      char_u		*buf_ffname,
      hash_T		*hash)
  {
  #ifdef FEAT_CSCOPE
      int		use_cscope = (st->flags & TAG_CSCOPE);
  #endif
      int		name_only = (st->flags & TAG_NAMES);
      int		mtt;
      int		len = 0;
      int		is_current;		// file name matches
      int		is_static;		// current tag line is static
      char_u	*mfp;
      char_u	*p;
      char_u	*s;
  
  #ifdef FEAT_CSCOPE
      if (use_cscope)
      {
  	// Don't change the ordering, always use the same table.
  	mtt = MT_GL_OTH;
      }
      else
  #endif
      {
  	// Decide in which array to store this match.
  	is_current = test_for_current(
  #ifdef FEAT_EMACS_TAGS
  		st->is_etag,
  #endif
  		tagpp->fname, tagpp->fname_end, st->tag_fname, buf_ffname);
  #ifdef FEAT_EMACS_TAGS
  	is_static = FALSE;
  	if (!st->is_etag)	// emacs tags are never static
  #endif
  	    is_static = test_for_static(tagpp);
  
  	// decide in which of the sixteen tables to store this
  	// match
  	if (is_static)
  	{
  	    if (is_current)
  		mtt = MT_ST_CUR;
  	    else
  		mtt = MT_ST_OTH;
  	}
  	else
  	{
  	    if (is_current)
  		mtt = MT_GL_CUR;
  	    else
  		mtt = MT_GL_OTH;
  	}
  	if (st->orgpat->regmatch.rm_ic && !margs->match_no_ic)
  	    mtt += MT_IC_OFF;
  	if (margs->match_re)
  	    mtt += MT_RE_OFF;
      }
  
      // Add the found match in ht_match[mtt] and ga_match[mtt].
      // Store the info we need later, which depends on the kind of
      // tags we are dealing with.
      if (st->help_only)
      {
  #ifdef FEAT_MULTI_LANG
  # define ML_EXTRA 3
  #else
  # define ML_EXTRA 0
  #endif
  	// Append the help-heuristic number after the tagname, for
  	// sorting it later.  The heuristic is ignored for
  	// detecting duplicates.
  	// The format is {tagname}@{lang}NUL{heuristic}NUL
  	*tagpp->tagname_end = NUL;
  	len = (int)(tagpp->tagname_end - tagpp->tagname);
  	mfp = alloc(sizeof(char_u) + len + 10 + ML_EXTRA + 1);
  	if (mfp != NULL)
  	{
  	    int heuristic;
  
  	    p = mfp;
  	    STRCPY(p, tagpp->tagname);
  #ifdef FEAT_MULTI_LANG
  	    p[len] = '@';
  	    STRCPY(p + len + 1, st->help_lang);
  #endif
  
  	    heuristic = help_heuristic(tagpp->tagname,
  				margs->match_re ? margs->matchoff : 0,
  				!margs->match_no_ic);
  #ifdef FEAT_MULTI_LANG
  	    heuristic += st->help_pri;
  #endif
  	    sprintf((char *)p + len + 1 + ML_EXTRA, "%06d",
  		    heuristic);
  	}
  	*tagpp->tagname_end = TAB;
      }
      else if (name_only)
      {
  	if (st->get_searchpat)
  	{
  	    char_u *temp_end = tagpp->command;
  
  	    if (*temp_end == '/')
  		while (*temp_end && *temp_end != '\r'
  			&& *temp_end != '\n'
  			&& *temp_end != '$')
  		    temp_end++;
  
  	    if (tagpp->command + 2 < temp_end)
  	    {
  		len = (int)(temp_end - tagpp->command - 2);
  		mfp = alloc(len + 2);
  		if (mfp != NULL)
  		    vim_strncpy(mfp, tagpp->command + 2, len);
  	    }
  	    else
  		mfp = NULL;
  	    st->get_searchpat = FALSE;
  	}
  	else
  	{
  	    len = (int)(tagpp->tagname_end - tagpp->tagname);
  	    mfp = alloc(sizeof(char_u) + len + 1);
  	    if (mfp != NULL)
  		vim_strncpy(mfp, tagpp->tagname, len);
  
  	    // if wanted, re-read line to get long form too
  	    if (State & INSERT)
  		st->get_searchpat = p_sft;
  	}
      }
      else
      {
  	size_t tag_fname_len = STRLEN(st->tag_fname);
  #ifdef FEAT_EMACS_TAGS
  	size_t ebuf_len = 0;
  #endif
  
  	// Save the tag in a buffer.
  	// Use 0x02 to separate fields (Can't use NUL because the
  	// hash key is terminated by NUL, or Ctrl_A because that is
  	// part of some Emacs tag files -- see parse_tag_line).
  	// Emacs tag: <mtt><tag_fname><0x02><ebuf><0x02><lbuf><NUL>
  	// other tag: <mtt><tag_fname><0x02><0x02><lbuf><NUL>
  	// without Emacs tags: <mtt><tag_fname><0x02><lbuf><NUL>
  	// Here <mtt> is the "mtt" value plus 1 to avoid NUL.
  	len = (int)tag_fname_len + (int)STRLEN(st->lbuf) + 3;
  #ifdef FEAT_EMACS_TAGS
  	if (st->is_etag)
  	{
  	    ebuf_len = STRLEN(st->ebuf);
  	    len += (int)ebuf_len + 1;
  	}
  	else
  	    ++len;
  #endif
  	mfp = alloc(sizeof(char_u) + len + 1);
  	if (mfp != NULL)
  	{
  	    p = mfp;
  	    p[0] = mtt + 1;
  	    STRCPY(p + 1, st->tag_fname);
  #ifdef BACKSLASH_IN_FILENAME
  	    // Ignore differences in slashes, avoid adding
  	    // both path/file and path\file.
  	    slash_adjust(p + 1);
  #endif
  	    p[tag_fname_len + 1] = TAG_SEP;
  	    s = p + 1 + tag_fname_len + 1;
  #ifdef FEAT_EMACS_TAGS
  	    if (st->is_etag)
  	    {
  		STRCPY(s, st->ebuf);
  		s[ebuf_len] = TAG_SEP;
  		s += ebuf_len + 1;
  	    }
  	    else
  		*s++ = TAG_SEP;
  #endif
  	    STRCPY(s, st->lbuf);
  	}
      }
  
      if (mfp != NULL)
      {
  	hashitem_T	*hi;
  
  	// Don't add identical matches.
  	// Add all cscope tags, because they are all listed.
  	// "mfp" is used as a hash key, there is a NUL byte to end
  	// the part that matters for comparing, more bytes may
  	// follow after it.  E.g. help tags store the priority
  	// after the NUL.
  #ifdef FEAT_CSCOPE
  	if (use_cscope)
  	    ++*hash;
  	else
  #endif
  	    *hash = hash_hash(mfp);
  	hi = hash_lookup(&st->ht_match[mtt], mfp, *hash);
  	if (HASHITEM_EMPTY(hi))
  	{
  	    if (hash_add_item(&st->ht_match[mtt], hi, mfp, *hash) == FAIL
  		    || ga_grow(&st->ga_match[mtt], 1) != OK)
  	    {
  		// Out of memory! Just forget about the rest.
  		st->stop_searching = TRUE;
  		return FAIL;
  	    }
  
  	    ((char_u **)(st->ga_match[mtt].ga_data))
  		[st->ga_match[mtt].ga_len++] = mfp;
  	    st->match_count++;
  	}
  	else
  	    // duplicate tag, drop it
  	    vim_free(mfp);
      }
  
      return OK;
  }
  
  /*
   * Read and get all the tags from file st->tag_fname.
   * Sets 'st->stop_searching' to TRUE to stop searching for additional tags.
   */
      static void
  findtags_get_all_tags(
      findtags_state_T		*st,
      findtags_match_args_T	*margs,
      char_u			*buf_ffname)
  {
      tagptrs_T		tagp;
      tagsearch_info_T	search_info;
      int			retval;
  #ifdef FEAT_CSCOPE
      int			use_cscope = (st->flags & TAG_CSCOPE);
  #endif
      hash_T		hash = 0;
  
      // This is only to avoid a compiler warning for using search_info
      // uninitialised.
      CLEAR_FIELD(search_info);
  
      // Read and parse the lines in the file one by one
      for (;;)
      {
  	// check for CTRL-C typed, more often when jumping around
  	if (st->state == TS_BINARY || st->state == TS_SKIP_BACK)
  	    line_breakcheck();
  	else
  	    fast_breakcheck();
  	if ((st->flags & TAG_INS_COMP))	// Double brackets for gcc
  	    ins_compl_check_keys(30, FALSE);
  	if (got_int || ins_compl_interrupted())
  	{
  	    st->stop_searching = TRUE;
  	    break;
  	}
  	// When mincount is TAG_MANY, stop when enough matches have been
  	// found (for completion).
  	if (st->mincount == TAG_MANY && st->match_count >= TAG_MANY)
  	{
  	    st->stop_searching = TRUE;
  	    break;
  	}
  	if (st->get_searchpat)
  	    goto line_read_in;
  
  	retval = findtags_get_next_line(st, &search_info);
  	if (retval == TAGS_READ_IGNORE)
  	    continue;
  	if (retval == TAGS_READ_EOF)
  	    break;
  
  line_read_in:
  
  	if (st->vimconv.vc_type != CONV_NONE)
  	    findtags_string_convert(st);
  
  #ifdef FEAT_EMACS_TAGS
  	// Emacs tags line with CTRL-L: New file name on next line.
  	// The file name is followed by a ','.
  	// Remember etag file name in ebuf.
  	if (*st->lbuf == Ctrl_L
  # ifdef FEAT_CSCOPE
  		&& !use_cscope
  # endif
  	   )
  	{
  	    st->is_etag = TRUE;		// in case at the start
  	    st->state = TS_LINEAR;
  	    emacs_tags_new_filename(st);
  	    continue;
  	}
  #endif
  
  	// When still at the start of the file, check for Emacs tags file
  	// format, and for "not sorted" flag.
  	if (st->state == TS_START)
  	{
  	    if (findtags_start_state_handler(st, &margs->sortic, &search_info) == FALSE)
  		continue;
  	}
  
  	// When the line is too long the NUL will not be in the
  	// last-but-one byte (see vim_fgets()).
  	// Has been reported for Mozilla JS with extremely long names.
  	// In that case we need to increase lbuf_size.
  	if (st->lbuf[st->lbuf_size - 2] != NUL
  #ifdef FEAT_CSCOPE
  		&& !use_cscope
  #endif
  	   )
  	{
  	    st->lbuf_size *= 2;
  	    vim_free(st->lbuf);
  	    st->lbuf = alloc(st->lbuf_size);
  	    if (st->lbuf == NULL)
  	    {
  		if (st->fp != NULL)
  		    fclose(st->fp);
  		st->fp = NULL;
  		st->stop_searching = TRUE;
  		return;
  	    }
  
  	    if (st->state == TS_STEP_FORWARD || st->state == TS_LINEAR)
  		// Seek to the same position to read the same line again
  		vim_ignored = vim_fseek(st->fp, search_info.curr_offset,
  								     SEEK_SET);
  	    // this will try the same thing again, make sure the offset is
  	    // different
  	    search_info.curr_offset = 0;
  	    continue;
  	}
  
  	retval = findtags_parse_line(st, &tagp, margs, &search_info);
  	if (retval == TAG_MATCH_NEXT)
  	    continue;
  	if (retval == TAG_MATCH_STOP)
  	    break;
  	if (retval == TAG_MATCH_FAIL)
  	{
  	    semsg(_(e_format_error_in_tags_file_str), st->tag_fname);
  #ifdef FEAT_CSCOPE
  	    if (!use_cscope)
  #endif
  		semsg(_("Before byte %ld"), (long)vim_ftell(st->fp));
  	    st->stop_searching = TRUE;
  	    return;
  	}
  
  	retval = findtags_match_tag(st, &tagp, margs);
  	if (retval == TAG_MATCH_NEXT)
  	    continue;
  	if (retval == TAG_MATCH_STOP)
  	    break;
  
  	// If a match is found, add it to ht_match[] and ga_match[].
  	if (retval == TAG_MATCH_SUCCESS)
  	{
  	    if (findtags_add_match(st, &tagp, margs, buf_ffname, &hash)
  								== FAIL)
  		break;
  	}
      } // forever
  }
  
  /*
   * Search for tags matching 'st->orgpat.pat' in the 'st->tag_fname' tags file.
   * Information needed to search for the tags is in the 'st' state structure.
   * The matching tags are returned in 'st'. If an error is encountered, then
   * 'st->stop_searching' is set to TRUE.
   */
      static void
  findtags_in_file(findtags_state_T *st, char_u *buf_ffname)
  {
      findtags_match_args_T margs;
  #ifdef FEAT_CSCOPE
      int		use_cscope = (st->flags & TAG_CSCOPE);
  #endif
  
      st->vimconv.vc_type = CONV_NONE;
      st->tag_file_sorted = NUL;
      st->fp = NULL;
      findtags_matchargs_init(&margs, st->flags);
  
      // A file that doesn't exist is silently ignored.  Only when not a
      // single file is found, an error message is given (further on).
  #ifdef FEAT_CSCOPE
      if (use_cscope)
  	st->fp = NULL;	    // avoid GCC warning
      else
  #endif
      {
  #ifdef FEAT_MULTI_LANG
  	if (curbuf->b_help)
  	{
  	    if (!findtags_in_help_init(st))
  		return;
  	}
  #endif
  
  	st->fp = mch_fopen((char *)st->tag_fname, "r");
  	if (st->fp == NULL)
  	    return;
  
  	if (p_verbose >= 5)
  	{
  	    verbose_enter();
  	    smsg(_("Searching tags file %s"), st->tag_fname);
  	    verbose_leave();
  	}
      }
      st->did_open = TRUE;	// remember that we found at least one file
  
      st->state = TS_START;	// we're at the start of the file
  #ifdef FEAT_EMACS_TAGS
      st->is_etag = FALSE;	// default is: not emacs style
  #endif
  
      // Read and parse the lines in the file one by one
      findtags_get_all_tags(st, &margs, buf_ffname);
  
      if (st->fp != NULL)
      {
  	fclose(st->fp);
  	st->fp = NULL;
      }
  #ifdef FEAT_EMACS_TAGS
      emacs_tags_incstack_free();
  #endif
      if (st->vimconv.vc_type != CONV_NONE)
  	convert_setup(&st->vimconv, NULL, NULL);
  
      if (margs.sort_error)
  	semsg(_(e_tags_file_not_sorted_str), st->tag_fname);
  
      // Stop searching if sufficient tags have been found.
      if (st->match_count >= st->mincount)
  	st->stop_searching = TRUE;
  }
  
  /*
   * Copy the tags found by find_tags() to 'matchesp'.
   * Returns the number of matches copied.
   */
      static int
  findtags_copy_matches(findtags_state_T *st, char_u ***matchesp)
  {
      int		name_only = (st->flags & TAG_NAMES);
      char_u	**matches;
      int		mtt;
      int		i;
      char_u	*mfp;
      char_u	*p;
  
      if (st->match_count > 0)
  	matches = ALLOC_MULT(char_u *, st->match_count);
      else
  	matches = NULL;
      st->match_count = 0;
      for (mtt = 0; mtt < MT_COUNT; ++mtt)
      {
  	for (i = 0; i < st->ga_match[mtt].ga_len; ++i)
  	{
  	    mfp = ((char_u **)(st->ga_match[mtt].ga_data))[i];
  	    if (matches == NULL)
  		vim_free(mfp);
  	    else
  	    {
  		if (!name_only)
  		{
  		    // Change mtt back to zero-based.
  		    *mfp = *mfp - 1;
  
  		    // change the TAG_SEP back to NUL
  		    for (p = mfp + 1; *p != NUL; ++p)
  			if (*p == TAG_SEP)
  			    *p = NUL;
  		}
  		matches[st->match_count++] = mfp;
  	    }
  	}
  
  	ga_clear(&st->ga_match[mtt]);
  	hash_clear(&st->ht_match[mtt]);
      }
  
      *matchesp = matches;
      return st->match_count;
  }
  
  /*
   * find_tags() - search for tags in tags files
   *
   * Return FAIL if search completely failed (*num_matches will be 0, *matchesp
   * will be NULL), OK otherwise.
   *
   * Priority depending on which type of tag is recognized:
   *  6.	A static or global tag with a full matching tag for the current file.
   *  5.	A global tag with a full matching tag for another file.
   *  4.	A static tag with a full matching tag for another file.
   *  3.	A static or global tag with an ignore-case matching tag for the
   *	current file.
   *  2.	A global tag with an ignore-case matching tag for another file.
   *  1.	A static tag with an ignore-case matching tag for another file.
   *
   * Tags in an emacs-style tags file are always global.
   *
   * flags:
   * TAG_HELP	  only search for help tags
   * TAG_NAMES	  only return name of tag
   * TAG_REGEXP	  use "pat" as a regexp
   * TAG_NOIC	  don't always ignore case
   * TAG_KEEP_LANG  keep language
   * TAG_CSCOPE	  use cscope results for tags
   * TAG_NO_TAGFUNC do not call the 'tagfunc' function
   */
      int
  find_tags(
      char_u	*pat,			// pattern to search for
      int		*num_matches,		// return: number of matches found
      char_u	***matchesp,		// return: array of matches found
      int		flags,
      int		mincount,		// MAXCOL: find all matches
  					// other: minimal number of matches
      char_u	*buf_ffname)		// name of buffer for priority
  {
      findtags_state_T	st;
      tagname_T	tn;			// info for get_tagfname()
      int		first_file;		// trying first tag file
      int		retval = FAIL;		// return value
      int		round;
  
      int		save_emsg_off;
  
      int		help_save;
  #ifdef FEAT_MULTI_LANG
      int		i;
      char_u	*saved_pat = NULL;		// copy of pat[]
  #endif
  
      int		findall = (mincount == MAXCOL || mincount == TAG_MANY);
  						// find all matching tags
      int		has_re = (flags & TAG_REGEXP);	// regexp used
      int		noic = (flags & TAG_NOIC);
  #ifdef FEAT_CSCOPE
      int		use_cscope = (flags & TAG_CSCOPE);
  #endif
      int		verbose = (flags & TAG_VERBOSE);
      int		save_p_ic = p_ic;
  
      /*
       * Change the value of 'ignorecase' according to 'tagcase' for the
       * duration of this function.
       */
      switch (curbuf->b_tc_flags ? curbuf->b_tc_flags : tc_flags)
      {
  	case TC_FOLLOWIC:		 break;
  	case TC_IGNORE:    p_ic = TRUE;  break;
  	case TC_MATCH:     p_ic = FALSE; break;
  	case TC_FOLLOWSCS: p_ic = ignorecase(pat); break;
  	case TC_SMART:     p_ic = ignorecase_opt(pat, TRUE, TRUE); break;
      }
  
      help_save = curbuf->b_help;
  
      if (findtags_state_init(&st, pat, flags, mincount) == FAIL)
  	goto findtag_end;
  
  #ifdef FEAT_CSCOPE
      STRCPY(st.tag_fname, "from cscope");	// for error messages
  #endif
  
      /*
       * Initialize a few variables
       */
      if (st.help_only)				// want tags from help file
  	curbuf->b_help = TRUE;			// will be restored later
  #ifdef FEAT_CSCOPE
      else if (use_cscope)
      {
  	// Make sure we don't mix help and cscope, confuses Coverity.
  	st.help_only = FALSE;
  	curbuf->b_help = FALSE;
      }
  #endif
  
  #ifdef FEAT_MULTI_LANG
      if (curbuf->b_help)
      {
  	// When "@ab" is specified use only the "ab" language, otherwise
  	// search all languages.
  	if (st.orgpat->len > 3 && pat[st.orgpat->len - 3] == '@'
  				&& ASCII_ISALPHA(pat[st.orgpat->len - 2])
  				&& ASCII_ISALPHA(pat[st.orgpat->len - 1]))
  	{
  	    saved_pat = vim_strnsave(pat, st.orgpat->len - 3);
  	    if (saved_pat != NULL)
  	    {
  		st.help_lang_find = &pat[st.orgpat->len - 2];
  		st.orgpat->pat = saved_pat;
  		st.orgpat->len -= 3;
  	    }
  	}
      }
  #endif
      if (p_tl != 0 && st.orgpat->len > p_tl)	// adjust for 'taglength'
  	st.orgpat->len = p_tl;
  
      save_emsg_off = emsg_off;
      emsg_off = TRUE;  // don't want error for invalid RE here
      prepare_pats(st.orgpat, has_re);
      emsg_off = save_emsg_off;
      if (has_re && st.orgpat->regmatch.regprog == NULL)
  	goto findtag_end;
  
  #ifdef FEAT_EVAL
      retval = findtags_apply_tfu(&st, pat, buf_ffname);
      if (retval != NOTDONE)
  	goto findtag_end;
  
      // re-initialize the default return value
      retval = FAIL;
  #endif
  
  #ifdef FEAT_MULTI_LANG
      // Set a flag if the file extension is .txt
      if ((flags & TAG_KEEP_LANG)
  	    && st.help_lang_find == NULL
  	    && curbuf->b_fname != NULL
  	    && (i = (int)STRLEN(curbuf->b_fname)) > 4
  	    && STRICMP(curbuf->b_fname + i - 4, ".txt") == 0)
  	st.is_txt = TRUE;
  #endif
  
      /*
       * When finding a specified number of matches, first try with matching
       * case, so binary search can be used, and try ignore-case matches in a
       * second loop.
       * When finding all matches, 'tagbsearch' is off, or there is no fixed
       * string to look for, ignore case right away to avoid going though the
       * tags files twice.
       * When the tag file is case-fold sorted, it is either one or the other.
       * Only ignore case when TAG_NOIC not used or 'ignorecase' set.
       */
      st.orgpat->regmatch.rm_ic = ((p_ic || !noic)
  			&& (findall || st.orgpat->headlen == 0 || !p_tbs));
      for (round = 1; round <= 2; ++round)
      {
  	st.linear = (st.orgpat->headlen == 0 || !p_tbs || round == 2);
  
        /*
         * Try tag file names from tags option one by one.
         */
        for (first_file = TRUE;
  #ifdef FEAT_CSCOPE
  	    use_cscope ||
  #endif
  		get_tagfname(&tn, first_file, st.tag_fname) == OK;
  							   first_file = FALSE)
        {
  	  findtags_in_file(&st, buf_ffname);
  	  if (st.stop_searching
  #ifdef FEAT_CSCOPE
  		  || use_cscope
  #endif
  	     )
  	  {
  	      retval = OK;
  	      break;
  	  }
        } // end of for-each-file loop
  
  #ifdef FEAT_CSCOPE
  	if (!use_cscope)
  #endif
  	    tagname_free(&tn);
  
  	// stop searching when already did a linear search, or when TAG_NOIC
  	// used, and 'ignorecase' not set or already did case-ignore search
  	if (st.stop_searching || st.linear || (!p_ic && noic) ||
  						st.orgpat->regmatch.rm_ic)
  	    break;
  # ifdef FEAT_CSCOPE
  	if (use_cscope)
  	    break;
  # endif
  
  	// try another time while ignoring case
  	st.orgpat->regmatch.rm_ic = TRUE;
      }
  
      if (!st.stop_searching)
      {
  	if (!st.did_open && verbose)	// never opened any tags file
  	    emsg(_(e_no_tags_file));
  	retval = OK;		// It's OK even when no tag found
      }
  
  findtag_end:
      findtags_state_free(&st);
  
      /*
       * Move the matches from the ga_match[] arrays into one list of
       * matches.  When retval == FAIL, free the matches.
       */
      if (retval == FAIL)
  	st.match_count = 0;
  
      *num_matches = findtags_copy_matches(&st, matchesp);
  
      curbuf->b_help = help_save;
  #ifdef FEAT_MULTI_LANG
      vim_free(saved_pat);
  #endif
  
      p_ic = save_p_ic;
  
      return retval;
  }
  
  static garray_T tag_fnames = GA_EMPTY;
  
  /*
   * Callback function for finding all "tags" and "tags-??" files in
   * 'runtimepath' doc directories.
   */
      static void
  found_tagfile_cb(char_u *fname, void *cookie UNUSED)
  {
      if (ga_grow(&tag_fnames, 1) == OK)
      {
  	char_u	*tag_fname = vim_strsave(fname);
  
  #ifdef BACKSLASH_IN_FILENAME
  	slash_adjust(tag_fname);
  #endif
  	simplify_filename(tag_fname);
  	((char_u **)(tag_fnames.ga_data))[tag_fnames.ga_len++] = tag_fname;
      }
  }
  
  #if defined(EXITFREE) || defined(PROTO)
      void
  free_tag_stuff(void)
  {
      ga_clear_strings(&tag_fnames);
      if (curwin != NULL)
  	do_tag(NULL, DT_FREE, 0, 0, 0);
      tag_freematch();
  
  # if defined(FEAT_QUICKFIX)
      tagstack_clear_entry(&ptag_entry);
  # endif
  }
  #endif
  
  /*
   * Get the next name of a tag file from the tag file list.
   * For help files, use "tags" file only.
   *
   * Return FAIL if no more tag file names, OK otherwise.
   */
      int
  get_tagfname(
      tagname_T	*tnp,	// holds status info
      int		first,	// TRUE when first file name is wanted
      char_u	*buf)	// pointer to buffer of MAXPATHL chars
  {
      char_u		*fname = NULL;
      char_u		*r_ptr;
      int			i;
  
      if (first)
  	CLEAR_POINTER(tnp);
  
      if (curbuf->b_help)
      {
  	/*
  	 * For help files it's done in a completely different way:
  	 * Find "doc/tags" and "doc/tags-??" in all directories in
  	 * 'runtimepath'.
  	 */
  	if (first)
  	{
  	    ga_clear_strings(&tag_fnames);
  	    ga_init2(&tag_fnames, sizeof(char_u *), 10);
  	    do_in_runtimepath((char_u *)
  #ifdef FEAT_MULTI_LANG
  # ifdef VMS
  		    // Functions decc$to_vms() and decc$translate_vms() crash
  		    // on some VMS systems with wildcards "??".  Seems ECO
  		    // patches do fix the problem in C RTL, but we can't use
  		    // an #ifdef for that.
  		    "doc/tags doc/tags-*"
  # else
  		    "doc/tags doc/tags-??"
  # endif
  #else
  		    "doc/tags"
  #endif
  					   , DIP_ALL, found_tagfile_cb, NULL);
  	}
  
  	if (tnp->tn_hf_idx >= tag_fnames.ga_len)
  	{
  	    // Not found in 'runtimepath', use 'helpfile', if it exists and
  	    // wasn't used yet, replacing "help.txt" with "tags".
  	    if (tnp->tn_hf_idx > tag_fnames.ga_len || *p_hf == NUL)
  		return FAIL;
  	    ++tnp->tn_hf_idx;
  	    STRCPY(buf, p_hf);
  	    STRCPY(gettail(buf), "tags");
  #ifdef BACKSLASH_IN_FILENAME
  	    slash_adjust(buf);
  #endif
  	    simplify_filename(buf);
  
  	    for (i = 0; i < tag_fnames.ga_len; ++i)
  		if (STRCMP(buf, ((char_u **)(tag_fnames.ga_data))[i]) == 0)
  		    return FAIL; // avoid duplicate file names
  	}
  	else
  	    vim_strncpy(buf, ((char_u **)(tag_fnames.ga_data))[
  					     tnp->tn_hf_idx++], MAXPATHL - 1);
  	return OK;
      }
  
      if (first)
      {
  	// Init.  We make a copy of 'tags', because autocommands may change
  	// the value without notifying us.
  	tnp->tn_tags = vim_strsave((*curbuf->b_p_tags != NUL)
  						 ? curbuf->b_p_tags : p_tags);
  	if (tnp->tn_tags == NULL)
  	    return FAIL;
  	tnp->tn_np = tnp->tn_tags;
      }
  
      /*
       * Loop until we have found a file name that can be used.
       * There are two states:
       * tnp->tn_did_filefind_init == FALSE: setup for next part in 'tags'.
       * tnp->tn_did_filefind_init == TRUE: find next file in this part.
       */
      for (;;)
      {
  	if (tnp->tn_did_filefind_init)
  	{
  	    fname = vim_findfile(tnp->tn_search_ctx);
  	    if (fname != NULL)
  		break;
  
  	    tnp->tn_did_filefind_init = FALSE;
  	}
  	else
  	{
  	    char_u  *filename = NULL;
  
  	    // Stop when used all parts of 'tags'.
  	    if (*tnp->tn_np == NUL)
  	    {
  		vim_findfile_cleanup(tnp->tn_search_ctx);
  		tnp->tn_search_ctx = NULL;
  		return FAIL;
  	    }
  
  	    /*
  	     * Copy next file name into buf.
  	     */
  	    buf[0] = NUL;
  	    (void)copy_option_part(&tnp->tn_np, buf, MAXPATHL - 1, " ,");
  
  #ifdef FEAT_PATH_EXTRA
  	    r_ptr = vim_findfile_stopdir(buf);
  #else
  	    r_ptr = NULL;
  #endif
  	    // move the filename one char forward and truncate the
  	    // filepath with a NUL
  	    filename = gettail(buf);
  	    STRMOVE(filename + 1, filename);
  	    *filename++ = NUL;
  
  	    tnp->tn_search_ctx = vim_findfile_init(buf, filename,
  		    r_ptr, 100,
  		    FALSE,	   // don't free visited list
  		    FINDFILE_FILE, // we search for a file
  		    tnp->tn_search_ctx, TRUE, curbuf->b_ffname);
  	    if (tnp->tn_search_ctx != NULL)
  		tnp->tn_did_filefind_init = TRUE;
  	}
      }
  
      STRCPY(buf, fname);
      vim_free(fname);
      return OK;
  }
  
  /*
   * Free the contents of a tagname_T that was filled by get_tagfname().
   */
      void
  tagname_free(tagname_T *tnp)
  {
      vim_free(tnp->tn_tags);
      vim_findfile_cleanup(tnp->tn_search_ctx);
      tnp->tn_search_ctx = NULL;
      ga_clear_strings(&tag_fnames);
  }
  
  /*
   * Parse one line from the tags file. Find start/end of tag name, start/end of
   * file name and start of search pattern.
   *
   * If is_etag is TRUE, tagp->fname and tagp->fname_end are not set.
   *
   * Return FAIL if there is a format error in this line, OK otherwise.
   */
      static int
  parse_tag_line(
      char_u	*lbuf,		// line to be parsed
  #ifdef FEAT_EMACS_TAGS
      int		is_etag,
  #endif
      tagptrs_T	*tagp)
  {
      char_u	*p;
  
  #ifdef FEAT_EMACS_TAGS
      if (is_etag)
  	// emacs-style tag file
  	return emacs_tags_parse_line(lbuf, tagp);
  #endif
  
      // Isolate the tagname, from lbuf up to the first white
      tagp->tagname = lbuf;
      p = vim_strchr(lbuf, TAB);
      if (p == NULL)
  	return FAIL;
      tagp->tagname_end = p;
  
      // Isolate file name, from first to second white space
      if (*p != NUL)
  	++p;
      tagp->fname = p;
      p = vim_strchr(p, TAB);
      if (p == NULL)
  	return FAIL;
      tagp->fname_end = p;
  
      // find start of search command, after second white space
      if (*p != NUL)
  	++p;
      if (*p == NUL)
  	return FAIL;
      tagp->command = p;
  
      return OK;
  }
  
  /*
   * Check if tagname is a static tag
   *
   * Static tags produced by the older ctags program have the format:
   *	'file:tag  file  /pattern'.
   * This is only recognized when both occurrence of 'file' are the same, to
   * avoid recognizing "string::string" or ":exit".
   *
   * Static tags produced by the new ctags program have the format:
   *	'tag  file  /pattern/;"<Tab>file:'	    "
   *
   * Return TRUE if it is a static tag and adjust *tagname to the real tag.
   * Return FALSE if it is not a static tag.
   */
      static int
  test_for_static(tagptrs_T *tagp)
  {
      char_u	*p;
  
      /*
       * Check for new style static tag ":...<Tab>file:[<Tab>...]"
       */
      p = tagp->command;
      while ((p = vim_strchr(p, '\t')) != NULL)
      {
  	++p;
  	if (STRNCMP(p, "file:", 5) == 0)
  	    return TRUE;
      }
  
      return FALSE;
  }
  
  /*
   * Returns the length of a matching tag line.
   */
      static size_t
  matching_line_len(char_u *lbuf)
  {
      char_u	*p = lbuf + 1;
  
      // does the same thing as parse_match()
      p += STRLEN(p) + 1;
  #ifdef FEAT_EMACS_TAGS
      p += STRLEN(p) + 1;
  #endif
      return (p - lbuf) + STRLEN(p);
  }
  
  /*
   * Parse a line from a matching tag.  Does not change the line itself.
   *
   * The line that we get looks like this:
   * Emacs tag: <mtt><tag_fname><NUL><ebuf><NUL><lbuf>
   * other tag: <mtt><tag_fname><NUL><NUL><lbuf>
   * without Emacs tags: <mtt><tag_fname><NUL><lbuf>
   *
   * Return OK or FAIL.
   */
      static int
  parse_match(
      char_u	*lbuf,	    // input: matching line
      tagptrs_T	*tagp)	    // output: pointers into the line
  {
      int		retval;
      char_u	*p;
      char_u	*pc, *pt;
  
      tagp->tag_fname = lbuf + 1;
      lbuf += STRLEN(tagp->tag_fname) + 2;
  #ifdef FEAT_EMACS_TAGS
      if (*lbuf)
      {
  	tagp->is_etag = TRUE;
  	tagp->fname = lbuf;
  	lbuf += STRLEN(lbuf);
  	tagp->fname_end = lbuf++;
      }
      else
      {
  	tagp->is_etag = FALSE;
  	++lbuf;
      }
  #endif
  
      // Find search pattern and the file name for non-etags.
      retval = parse_tag_line(lbuf,
  #ifdef FEAT_EMACS_TAGS
  			tagp->is_etag,
  #endif
  			tagp);
  
      tagp->tagkind = NULL;
      tagp->user_data = NULL;
      tagp->tagline = 0;
      tagp->command_end = NULL;
  
      if (retval == OK)
      {
  	// Try to find a kind field: "kind:<kind>" or just "<kind>"
  	p = tagp->command;
  	if (find_extra(&p) == OK)
  	{
  	    if (p > tagp->command && p[-1] == '|')
  		tagp->command_end = p - 1;  // drop trailing bar
  	    else
  		tagp->command_end = p;
  	    p += 2;	// skip ";\""
  	    if (*p++ == TAB)
  		// Accept ASCII alphabetic kind characters and any multi-byte
  		// character.
  		while (ASCII_ISALPHA(*p) || mb_ptr2len(p) > 1)
  		{
  		    if (STRNCMP(p, "kind:", 5) == 0)
  			tagp->tagkind = p + 5;
  		    else if (STRNCMP(p, "user_data:", 10) == 0)
  			tagp->user_data = p + 10;
  		    else if (STRNCMP(p, "line:", 5) == 0)
  			tagp->tagline = atoi((char *)p + 5);
  		    if (tagp->tagkind != NULL && tagp->user_data != NULL)
  			break;
  		    pc = vim_strchr(p, ':');
  		    pt = vim_strchr(p, '\t');
  		    if (pc == NULL || (pt != NULL && pc > pt))
  			tagp->tagkind = p;
  		    if (pt == NULL)
  			break;
  		    p = pt;
  		    MB_PTR_ADV(p);
  		}
  	}
  	if (tagp->tagkind != NULL)
  	{
  	    for (p = tagp->tagkind;
  			    *p && *p != '\t' && *p != '\r' && *p != '\n'; MB_PTR_ADV(p))
  		;
  	    tagp->tagkind_end = p;
  	}
  	if (tagp->user_data != NULL)
  	{
  	    for (p = tagp->user_data;
  			    *p && *p != '\t' && *p != '\r' && *p != '\n'; MB_PTR_ADV(p))
  		;
  	    tagp->user_data_end = p;
  	}
      }
      return retval;
  }
  
  /*
   * Find out the actual file name of a tag.  Concatenate the tags file name
   * with the matching tag file name.
   * Returns an allocated string or NULL (out of memory).
   */
      static char_u *
  tag_full_fname(tagptrs_T *tagp)
  {
      char_u	*fullname;
      int		c;
  
  #ifdef FEAT_EMACS_TAGS
      if (tagp->is_etag)
  	c = 0;	    // to shut up GCC
      else
  #endif
      {
  	c = *tagp->fname_end;
  	*tagp->fname_end = NUL;
      }
      fullname = expand_tag_fname(tagp->fname, tagp->tag_fname, FALSE);
  
  #ifdef FEAT_EMACS_TAGS
      if (!tagp->is_etag)
  #endif
  	*tagp->fname_end = c;
  
      return fullname;
  }
  
  /*
   * Jump to a tag that has been found in one of the tag files
   *
   * returns OK for success, NOTAGFILE when file not found, FAIL otherwise.
   */
      static int
  jumpto_tag(
      char_u	*lbuf_arg,	// line from the tags file for this tag
      int		forceit,	// :ta with !
      int		keep_help)	// keep help flag (FALSE for cscope)
  {
      optmagic_T	save_magic_overruled;
      int		save_p_ws, save_p_scs, save_p_ic;
      linenr_T	save_lnum;
      char_u	*str;
      char_u	*pbuf;			// search pattern buffer
      char_u	*pbuf_end;
      char_u	*tofree_fname = NULL;
      char_u	*fname;
      tagptrs_T	tagp;
      int		retval = FAIL;
      int		getfile_result = GETFILE_UNUSED;
      int		search_options;
  #ifdef FEAT_SEARCH_EXTRA
      int		save_no_hlsearch;
  #endif
  #if defined(FEAT_QUICKFIX)
      win_T	*curwin_save = NULL;
  #endif
      char_u	*full_fname = NULL;
  #ifdef FEAT_FOLDING
      int		old_KeyTyped = KeyTyped;    // getting the file may reset it
  #endif
      size_t	len;
      char_u	*lbuf;
  
      // Make a copy of the line, it can become invalid when an autocommand calls
      // back here recursively.
      len = matching_line_len(lbuf_arg) + 1;
      lbuf = alloc(len);
      if (lbuf != NULL)
  	mch_memmove(lbuf, lbuf_arg, len);
  
      pbuf = alloc(LSIZE);
  
      // parse the match line into the tagp structure
      if (pbuf == NULL || lbuf == NULL || parse_match(lbuf, &tagp) == FAIL)
      {
  	tagp.fname_end = NULL;
  	goto erret;
      }
  
      // truncate the file name, so it can be used as a string
      *tagp.fname_end = NUL;
      fname = tagp.fname;
  
      // copy the command to pbuf[], remove trailing CR/NL
      str = tagp.command;
      for (pbuf_end = pbuf; *str && *str != '\n' && *str != '\r'; )
      {
  #ifdef FEAT_EMACS_TAGS
  	if (tagp.is_etag && *str == ',')// stop at ',' after line number
  	    break;
  #endif
  	*pbuf_end++ = *str++;
  	if (pbuf_end - pbuf + 1 >= LSIZE)
  	    break;
      }
      *pbuf_end = NUL;
  
  #ifdef FEAT_EMACS_TAGS
      if (!tagp.is_etag)
  #endif
      {
  	/*
  	 * Remove the "<Tab>fieldname:value" stuff; we don't need it here.
  	 */
  	str = pbuf;
  	if (find_extra(&str) == OK)
  	{
  	    pbuf_end = str;
  	    *pbuf_end = NUL;
  	}
      }
  
      /*
       * Expand file name, when needed (for environment variables).
       * If 'tagrelative' option set, may change file name.
       */
      fname = expand_tag_fname(fname, tagp.tag_fname, TRUE);
      if (fname == NULL)
  	goto erret;
      tofree_fname = fname;	// free() it later
  
      /*
       * Check if the file with the tag exists before abandoning the current
       * file.  Also accept a file name for which there is a matching BufReadCmd
       * autocommand event (e.g., http://sys/file).
       */
      if (mch_getperm(fname) < 0 && !has_autocmd(EVENT_BUFREADCMD, fname, NULL))
      {
  	retval = NOTAGFILE;
  	vim_free(nofile_fname);
  	nofile_fname = vim_strsave(fname);
  	if (nofile_fname == NULL)
  	    nofile_fname = empty_option;
  	goto erret;
      }
  
      ++RedrawingDisabled;
  
  #ifdef FEAT_GUI
      need_mouse_correct = TRUE;
  #endif
  
  #if defined(FEAT_QUICKFIX)
      if (g_do_tagpreview != 0)
      {
  	postponed_split = 0;	// don't split again below
  	curwin_save = curwin;	// Save current window
  
  	/*
  	 * If we are reusing a window, we may change dir when
  	 * entering it (autocommands) so turn the tag filename
  	 * into a fullpath
  	 */
  	if (!curwin->w_p_pvw)
  	{
  	    full_fname = FullName_save(fname, FALSE);
  	    fname = full_fname;
  
  	    /*
  	     * Make the preview window the current window.
  	     * Open a preview window when needed.
  	     */
  	    prepare_tagpreview(TRUE, TRUE, FALSE);
  	}
      }
  
      // If it was a CTRL-W CTRL-] command split window now.  For ":tab tag"
      // open a new tab page.
      if (postponed_split && (swb_flags & (SWB_USEOPEN | SWB_USETAB)))
      {
  	buf_T *existing_buf = buflist_findname_exp(fname);
  
  	if (existing_buf != NULL)
  	{
  	    win_T *wp = NULL;
  
  	    if (swb_flags & SWB_USEOPEN)
  		wp = buf_jump_open_win(existing_buf);
  
  	    // If 'switchbuf' contains "usetab": jump to first window in any tab
  	    // page containing "existing_buf" if one exists
  	    if (wp == NULL && (swb_flags & SWB_USETAB))
  		wp = buf_jump_open_tab(existing_buf);
  	    // We've switched to the buffer, the usual loading of the file must
  	    // be skipped.
  	    if (wp != NULL)
  		getfile_result = GETFILE_SAME_FILE;
  	}
      }
      if (getfile_result == GETFILE_UNUSED
  				  && (postponed_split || cmdmod.cmod_tab != 0))
      {
  	if (win_split(postponed_split > 0 ? postponed_split : 0,
  						postponed_split_flags) == FAIL)
  	{
  	    --RedrawingDisabled;
  	    goto erret;
  	}
  	RESET_BINDING(curwin);
      }
  #endif
  
      if (keep_help)
      {
  	// A :ta from a help file will keep the b_help flag set.  For ":ptag"
  	// we need to use the flag from the window where we came from.
  #if defined(FEAT_QUICKFIX)
  	if (g_do_tagpreview != 0)
  	    keep_help_flag = bt_help(curwin_save->w_buffer);
  	else
  #endif
  	    keep_help_flag = curbuf->b_help;
      }
  
      if (getfile_result == GETFILE_UNUSED)
  	// Careful: getfile() may trigger autocommands and call jumpto_tag()
  	// recursively.
  	getfile_result = getfile(0, fname, NULL, TRUE, (linenr_T)0, forceit);
      keep_help_flag = FALSE;
  
      if (GETFILE_SUCCESS(getfile_result))	// got to the right file
      {
  	curwin->w_set_curswant = TRUE;
  	postponed_split = 0;
  
  	save_magic_overruled = magic_overruled;
  	magic_overruled = OPTION_MAGIC_OFF;	// always execute with 'nomagic'
  #ifdef FEAT_SEARCH_EXTRA
  	// Save value of no_hlsearch, jumping to a tag is not a real search
  	save_no_hlsearch = no_hlsearch;
  #endif
  #if defined(FEAT_PROP_POPUP) && defined(FEAT_QUICKFIX)
  	// getfile() may have cleared options, apply 'previewpopup' again.
  	if (g_do_tagpreview != 0 && *p_pvp != NUL)
  	    parse_previewpopup(curwin);
  #endif
  
  	/*
  	 * If 'cpoptions' contains 't', store the search pattern for the "n"
  	 * command.  If 'cpoptions' does not contain 't', the search pattern
  	 * is not stored.
  	 */
  	if (vim_strchr(p_cpo, CPO_TAGPAT) != NULL)
  	    search_options = 0;
  	else
  	    search_options = SEARCH_KEEP;
  
  	/*
  	 * If the command is a search, try here.
  	 *
  	 * Reset 'smartcase' for the search, since the search pattern was not
  	 * typed by the user.
  	 * Only use do_search() when there is a full search command, without
  	 * anything following.
  	 */
  	str = pbuf;
  	if (pbuf[0] == '/' || pbuf[0] == '?')
  	    str = skip_regexp(pbuf + 1, pbuf[0], FALSE) + 1;
  	if (str > pbuf_end - 1)	// search command with nothing following
  	{
  	    save_p_ws = p_ws;
  	    save_p_ic = p_ic;
  	    save_p_scs = p_scs;
  	    p_ws = TRUE;	// need 'wrapscan' for backward searches
  	    p_ic = FALSE;	// don't ignore case now
  	    p_scs = FALSE;
  	    save_lnum = curwin->w_cursor.lnum;
  	    if (tagp.tagline > 0)
  		// start search before line from "line:" field
  		curwin->w_cursor.lnum = tagp.tagline - 1;
  	    else
  		// start search before first line
  		curwin->w_cursor.lnum = 0;
  	    if (do_search(NULL, pbuf[0], pbuf[0], pbuf + 1, (long)1,
  							 search_options, NULL))
  		retval = OK;
  	    else
  	    {
  		int	found = 1;
  		int	cc;
  
  		/*
  		 * try again, ignore case now
  		 */
  		p_ic = TRUE;
  		if (!do_search(NULL, pbuf[0], pbuf[0], pbuf + 1, (long)1,
  							 search_options, NULL))
  		{
  		    /*
  		     * Failed to find pattern, take a guess: "^func  ("
  		     */
  		    found = 2;
  		    (void)test_for_static(&tagp);
  		    cc = *tagp.tagname_end;
  		    *tagp.tagname_end = NUL;
  		    sprintf((char *)pbuf, "^%s\\s\\*(", tagp.tagname);
  		    if (!do_search(NULL, '/', '/', pbuf, (long)1,
  							 search_options, NULL))
  		    {
  			// Guess again: "^char * \<func  ("
  			sprintf((char *)pbuf, "^\\[#a-zA-Z_]\\.\\*\\<%s\\s\\*(",
  								tagp.tagname);
  			if (!do_search(NULL, '/', '/', pbuf, (long)1,
  							 search_options, NULL))
  			    found = 0;
  		    }
  		    *tagp.tagname_end = cc;
  		}
  		if (found == 0)
  		{
  		    emsg(_(e_canot_find_tag_pattern));
  		    curwin->w_cursor.lnum = save_lnum;
  		}
  		else
  		{
  		    /*
  		     * Only give a message when really guessed, not when 'ic'
  		     * is set and match found while ignoring case.
  		     */
  		    if (found == 2 || !save_p_ic)
  		    {
  			msg(_(e_couldnt_find_tag_just_guessing));
  			if (!msg_scrolled && msg_silent == 0)
  			{
  			    out_flush();
  			    ui_delay(1010L, TRUE);
  			}
  		    }
  		    retval = OK;
  		}
  	    }
  	    p_ws = save_p_ws;
  	    p_ic = save_p_ic;
  	    p_scs = save_p_scs;
  
  	    // A search command may have positioned the cursor beyond the end
  	    // of the line.  May need to correct that here.
  	    check_cursor();
  	}
  	else
  	{
  	    int		save_secure = secure;
  
  	    // Setup the sandbox for executing the command from the tags file.
  	    secure = 1;
  #ifdef HAVE_SANDBOX
  	    ++sandbox;
  #endif
  	    curwin->w_cursor.lnum = 1;		// start command in line 1
  	    do_cmdline_cmd(pbuf);
  	    retval = OK;
  
  	    // When the command has done something that is not allowed make
  	    // sure the error message can be seen.
  	    if (secure == 2)
  		wait_return(TRUE);
  	    secure = save_secure;
  #ifdef HAVE_SANDBOX
  	    --sandbox;
  #endif
  	}
  
  	magic_overruled = save_magic_overruled;
  #ifdef FEAT_SEARCH_EXTRA
  	// restore no_hlsearch when keeping the old search pattern
  	if (search_options)
  	    set_no_hlsearch(save_no_hlsearch);
  #endif
  
  	// Return OK if jumped to another file (at least we found the file!).
  	if (getfile_result == GETFILE_OPEN_OTHER)
  	    retval = OK;
  
  	if (retval == OK)
  	{
  	    /*
  	     * For a help buffer: Put the cursor line at the top of the window,
  	     * the help subject will be below it.
  	     */
  	    if (curbuf->b_help)
  		set_topline(curwin, curwin->w_cursor.lnum);
  #ifdef FEAT_FOLDING
  	    if ((fdo_flags & FDO_TAG) && old_KeyTyped)
  		foldOpenCursor();
  #endif
  	}
  
  #if defined(FEAT_QUICKFIX)
  	if (g_do_tagpreview != 0
  			   && curwin != curwin_save && win_valid(curwin_save))
  	{
  	    // Return cursor to where we were
  	    validate_cursor();
  	    redraw_later(VALID);
  	    win_enter(curwin_save, TRUE);
  	}
  #endif
  
  	--RedrawingDisabled;
      }
      else
      {
  	--RedrawingDisabled;
  	got_int = FALSE;  // don't want entering window to fail
  
  	if (postponed_split)		// close the window
  	{
  	    win_close(curwin, FALSE);
  	    postponed_split = 0;
  	}
  #if defined(FEAT_QUICKFIX) && defined(FEAT_PROP_POPUP)
  	else if (WIN_IS_POPUP(curwin))
  	{
  	    win_T   *wp = curwin;
  
  	    if (win_valid(curwin_save))
  		win_enter(curwin_save, TRUE);
  	    popup_close(wp->w_id, FALSE);
  	}
  #endif
      }
  #if defined(FEAT_QUICKFIX) && defined(FEAT_PROP_POPUP)
      if (WIN_IS_POPUP(curwin))
  	// something went wrong, still in popup, but it can't have focus
  	win_enter(firstwin, TRUE);
  #endif
  
  erret:
  #if defined(FEAT_QUICKFIX)
      g_do_tagpreview = 0; // For next time
  #endif
      vim_free(lbuf);
      vim_free(pbuf);
      vim_free(tofree_fname);
      vim_free(full_fname);
  
      return retval;
  }
  
  /*
   * If "expand" is TRUE, expand wildcards in fname.
   * If 'tagrelative' option set, change fname (name of file containing tag)
   * according to tag_fname (name of tag file containing fname).
   * Returns a pointer to allocated memory (or NULL when out of memory).
   */
      static char_u *
  expand_tag_fname(char_u *fname, char_u *tag_fname, int expand)
  {
      char_u	*p;
      char_u	*retval;
      char_u	*expanded_fname = NULL;
      expand_T	xpc;
  
      /*
       * Expand file name (for environment variables) when needed.
       */
      if (expand && mch_has_wildcard(fname))
      {
  	ExpandInit(&xpc);
  	xpc.xp_context = EXPAND_FILES;
  	expanded_fname = ExpandOne(&xpc, fname, NULL,
  			    WILD_LIST_NOTFOUND|WILD_SILENT, WILD_EXPAND_FREE);
  	if (expanded_fname != NULL)
  	    fname = expanded_fname;
      }
  
      if ((p_tr || curbuf->b_help)
  	    && !vim_isAbsName(fname)
  	    && (p = gettail(tag_fname)) != tag_fname)
      {
  	retval = alloc(MAXPATHL);
  	if (retval != NULL)
  	{
  	    STRCPY(retval, tag_fname);
  	    vim_strncpy(retval + (p - tag_fname), fname,
  					      MAXPATHL - (p - tag_fname) - 1);
  	    /*
  	     * Translate names like "src/a/../b/file.c" into "src/b/file.c".
  	     */
  	    simplify_filename(retval);
  	}
      }
      else
  	retval = vim_strsave(fname);
  
      vim_free(expanded_fname);
  
      return retval;
  }
  
  /*
   * Check if we have a tag for the buffer with name "buf_ffname".
   * This is a bit slow, because of the full path compare in fullpathcmp().
   * Return TRUE if tag for file "fname" if tag file "tag_fname" is for current
   * file.
   */
      static int
  test_for_current(
  #ifdef FEAT_EMACS_TAGS
      int	    is_etag,
  #endif
      char_u  *fname,
      char_u  *fname_end,
      char_u  *tag_fname,
      char_u  *buf_ffname)
  {
      int	    c;
      int	    retval = FALSE;
      char_u  *fullname;
  
      if (buf_ffname != NULL)	// if the buffer has a name
      {
  #ifdef FEAT_EMACS_TAGS
  	if (is_etag)
  	    c = 0;	    // to shut up GCC
  	else
  #endif
  	{
  	    c = *fname_end;
  	    *fname_end = NUL;
  	}
  	fullname = expand_tag_fname(fname, tag_fname, TRUE);
  	if (fullname != NULL)
  	{
  	    retval = (fullpathcmp(fullname, buf_ffname, TRUE, TRUE) & FPC_SAME);
  	    vim_free(fullname);
  	}
  #ifdef FEAT_EMACS_TAGS
  	if (!is_etag)
  #endif
  	    *fname_end = c;
      }
  
      return retval;
  }
  
  /*
   * Find the end of the tagaddress.
   * Return OK if ";\"" is following, FAIL otherwise.
   */
      static int
  find_extra(char_u **pp)
  {
      char_u	*str = *pp;
      char_u	first_char = **pp;
  
      // Repeat for addresses separated with ';'
      for (;;)
      {
  	if (VIM_ISDIGIT(*str))
  	    str = skipdigits(str + 1);
  	else if (*str == '/' || *str == '?')
  	{
  	    str = skip_regexp(str + 1, *str, FALSE);
  	    if (*str != first_char)
  		str = NULL;
  	    else
  		++str;
  	}
  	else
  	{
  	    // not a line number or search string, look for terminator.
  	    str = (char_u *)strstr((char *)str, "|;\"");
  	    if (str != NULL)
  	    {
  		++str;
  		break;
  	    }
  
  	}
  	if (str == NULL || *str != ';'
  		  || !(VIM_ISDIGIT(str[1]) || str[1] == '/' || str[1] == '?'))
  	    break;
  	++str;	// skip ';'
  	first_char = *str;
      }
  
      if (str != NULL && STRNCMP(str, ";\"", 2) == 0)
      {
  	*pp = str;
  	return OK;
      }
      return FAIL;
  }
  
  /*
   * Free a single entry in a tag stack
   */
      static void
  tagstack_clear_entry(taggy_T *item)
  {
      VIM_CLEAR(item->tagname);
      VIM_CLEAR(item->user_data);
  }
  
      int
  expand_tags(
      int		tagnames,	// expand tag names
      char_u	*pat,
      int		*num_file,
      char_u	***file)
  {
      int		i;
      int		extra_flag;
      char_u	*name_buf;
      size_t	name_buf_size = 100;
      tagptrs_T	t_p;
      int		ret;
  
      name_buf = alloc(name_buf_size);
      if (name_buf == NULL)
  	return FAIL;
  
      if (tagnames)
  	extra_flag = TAG_NAMES;
      else
  	extra_flag = 0;
      if (pat[0] == '/')
  	ret = find_tags(pat + 1, num_file, file,
  		TAG_REGEXP | extra_flag | TAG_VERBOSE | TAG_NO_TAGFUNC,
  		TAG_MANY, curbuf->b_ffname);
      else
  	ret = find_tags(pat, num_file, file,
  	      TAG_REGEXP | extra_flag | TAG_VERBOSE | TAG_NO_TAGFUNC | TAG_NOIC,
  		TAG_MANY, curbuf->b_ffname);
      if (ret == OK && !tagnames)
      {
  	 // Reorganize the tags for display and matching as strings of:
  	 // "<tagname>\0<kind>\0<filename>\0"
  	 for (i = 0; i < *num_file; i++)
  	 {
  	     size_t	len;
  
  	     parse_match((*file)[i], &t_p);
  	     len = t_p.tagname_end - t_p.tagname;
  	     if (len > name_buf_size - 3)
  	     {
  		 char_u *buf;
  
  		 name_buf_size = len + 3;
  		 buf = vim_realloc(name_buf, name_buf_size);
  		 if (buf == NULL)
  		 {
  		     vim_free(name_buf);
  		     return FAIL;
  		 }
  		 name_buf = buf;
  	     }
  
  	     mch_memmove(name_buf, t_p.tagname, len);
  	     name_buf[len++] = 0;
  	     name_buf[len++] = (t_p.tagkind != NULL && *t_p.tagkind)
  							  ? *t_p.tagkind : 'f';
  	     name_buf[len++] = 0;
  	     mch_memmove((*file)[i] + len, t_p.fname,
  						    t_p.fname_end - t_p.fname);
  	     (*file)[i][len + (t_p.fname_end - t_p.fname)] = 0;
  	     mch_memmove((*file)[i], name_buf, len);
  	}
      }
  
      vim_free(name_buf);
      return ret;
  }
  
  #if defined(FEAT_EVAL) || defined(PROTO)
  /*
   * Add a tag field to the dictionary "dict".
   * Return OK or FAIL.
   */
      static int
  add_tag_field(
      dict_T  *dict,
      char    *field_name,
      char_u  *start,		// start of the value
      char_u  *end)		// after the value; can be NULL
  {
      char_u	*buf;
      int		len = 0;
      int		retval;
  
      // check that the field name doesn't exist yet
      if (dict_find(dict, (char_u *)field_name, -1) != NULL)
      {
  	if (p_verbose > 0)
  	{
  	    verbose_enter();
  	    smsg(_("Duplicate field name: %s"), field_name);
  	    verbose_leave();
  	}
  	return FAIL;
      }
      buf = alloc(MAXPATHL);
      if (buf == NULL)
  	return FAIL;
      if (start != NULL)
      {
  	if (end == NULL)
  	{
  	    end = start + STRLEN(start);
  	    while (end > start && (end[-1] == '\r' || end[-1] == '\n'))
  		--end;
  	}
  	len = (int)(end - start);
  	if (len > MAXPATHL - 1)
  	    len = MAXPATHL - 1;
  	vim_strncpy(buf, start, len);
      }
      buf[len] = NUL;
      retval = dict_add_string(dict, field_name, buf);
      vim_free(buf);
      return retval;
  }
  
  /*
   * Add the tags matching the specified pattern "pat" to the list "list"
   * as a dictionary. Use "buf_fname" for priority, unless NULL.
   */
      int
  get_tags(list_T *list, char_u *pat, char_u *buf_fname)
  {
      int		num_matches, i, ret;
      char_u	**matches, *p;
      char_u	*full_fname;
      dict_T	*dict;
      tagptrs_T	tp;
      long	is_static;
  
      ret = find_tags(pat, &num_matches, &matches,
  				TAG_REGEXP | TAG_NOIC, (int)MAXCOL, buf_fname);
      if (ret == OK && num_matches > 0)
      {
  	for (i = 0; i < num_matches; ++i)
  	{
  	    parse_match(matches[i], &tp);
  	    is_static = test_for_static(&tp);
  
  	    // Skip pseudo-tag lines.
  	    if (STRNCMP(tp.tagname, "!_TAG_", 6) == 0)
  	    {
  		vim_free(matches[i]);
  		continue;
  	    }
  
  	    if ((dict = dict_alloc()) == NULL)
  		ret = FAIL;
  	    if (list_append_dict(list, dict) == FAIL)
  		ret = FAIL;
  
  	    full_fname = tag_full_fname(&tp);
  	    if (add_tag_field(dict, "name", tp.tagname, tp.tagname_end) == FAIL
  		    || add_tag_field(dict, "filename", full_fname,
  							 NULL) == FAIL
  		    || add_tag_field(dict, "cmd", tp.command,
  						       tp.command_end) == FAIL
  		    || add_tag_field(dict, "kind", tp.tagkind,
  						      tp.tagkind_end) == FAIL
  		    || dict_add_number(dict, "static", is_static) == FAIL)
  		ret = FAIL;
  
  	    vim_free(full_fname);
  
  	    if (tp.command_end != NULL)
  	    {
  		for (p = tp.command_end + 3;
  			  *p != NUL && *p != '\n' && *p != '\r'; MB_PTR_ADV(p))
  		{
  		    if (p == tp.tagkind || (p + 5 == tp.tagkind
  					      && STRNCMP(p, "kind:", 5) == 0))
  			// skip "kind:<kind>" and "<kind>"
  			p = tp.tagkind_end - 1;
  		    else if (STRNCMP(p, "file:", 5) == 0)
  			// skip "file:" (static tag)
  			p += 4;
  		    else if (!VIM_ISWHITE(*p))
  		    {
  			char_u	*s, *n;
  			int	len;
  
  			// Add extra field as a dict entry.  Fields are
  			// separated by Tabs.
  			n = p;
  			while (*p != NUL && *p >= ' ' && *p < 127 && *p != ':')
  			    ++p;
  			len = (int)(p - n);
  			if (*p == ':' && len > 0)
  			{
  			    s = ++p;
  			    while (*p != NUL && *p >= ' ')
  				++p;
  			    n[len] = NUL;
  			    if (add_tag_field(dict, (char *)n, s, p) == FAIL)
  				ret = FAIL;
  			    n[len] = ':';
  			}
  			else
  			    // Skip field without colon.
  			    while (*p != NUL && *p >= ' ')
  				++p;
  			if (*p == NUL)
  			    break;
  		    }
  		}
  	    }
  
  	    vim_free(matches[i]);
  	}
  	vim_free(matches);
      }
      return ret;
  }
  
  /*
   * Return information about 'tag' in dict 'retdict'.
   */
      static void
  get_tag_details(taggy_T *tag, dict_T *retdict)
  {
      list_T	*pos;
      fmark_T	*fmark;
  
      dict_add_string(retdict, "tagname", tag->tagname);
      dict_add_number(retdict, "matchnr", tag->cur_match + 1);
      dict_add_number(retdict, "bufnr", tag->cur_fnum);
      if (tag->user_data)
  	dict_add_string(retdict, "user_data", tag->user_data);
  
      if ((pos = list_alloc_id(aid_tagstack_from)) == NULL)
  	return;
      dict_add_list(retdict, "from", pos);
  
      fmark = &tag->fmark;
      list_append_number(pos,
  			(varnumber_T)(fmark->fnum != -1 ? fmark->fnum : 0));
      list_append_number(pos, (varnumber_T)fmark->mark.lnum);
      list_append_number(pos, (varnumber_T)(fmark->mark.col == MAXCOL ?
  					MAXCOL : fmark->mark.col + 1));
      list_append_number(pos, (varnumber_T)fmark->mark.coladd);
  }
  
  /*
   * Return the tag stack entries of the specified window 'wp' in dictionary
   * 'retdict'.
   */
      void
  get_tagstack(win_T *wp, dict_T *retdict)
  {
      list_T	*l;
      int		i;
      dict_T	*d;
  
      dict_add_number(retdict, "length", wp->w_tagstacklen);
      dict_add_number(retdict, "curidx", wp->w_tagstackidx + 1);
      l = list_alloc_id(aid_tagstack_items);
      if (l == NULL)
  	return;
      dict_add_list(retdict, "items", l);
  
      for (i = 0; i < wp->w_tagstacklen; i++)
      {
  	if ((d = dict_alloc_id(aid_tagstack_details)) == NULL)
  	    return;
  	list_append_dict(l, d);
  
  	get_tag_details(&wp->w_tagstack[i], d);
      }
  }
  
  /*
   * Free all the entries in the tag stack of the specified window
   */
      static void
  tagstack_clear(win_T *wp)
  {
      int i;
  
      // Free the current tag stack
      for (i = 0; i < wp->w_tagstacklen; ++i)
  	tagstack_clear_entry(&wp->w_tagstack[i]);
      wp->w_tagstacklen = 0;
      wp->w_tagstackidx = 0;
  }
  
  /*
   * Remove the oldest entry from the tag stack and shift the rest of
   * the entries to free up the top of the stack.
   */
      static void
  tagstack_shift(win_T *wp)
  {
      taggy_T	*tagstack = wp->w_tagstack;
      int		i;
  
      tagstack_clear_entry(&tagstack[0]);
      for (i = 1; i < wp->w_tagstacklen; ++i)
  	tagstack[i - 1] = tagstack[i];
      wp->w_tagstacklen--;
  }
  
  /*
   * Push a new item to the tag stack
   */
      static void
  tagstack_push_item(
  	win_T	*wp,
  	char_u	*tagname,
  	int	cur_fnum,
  	int	cur_match,
  	pos_T	mark,
  	int	fnum,
  	char_u  *user_data)
  {
      taggy_T	*tagstack = wp->w_tagstack;
      int		idx = wp->w_tagstacklen;	// top of the stack
  
      // if the tagstack is full: remove the oldest entry
      if (idx >= TAGSTACKSIZE)
      {
  	tagstack_shift(wp);
  	idx = TAGSTACKSIZE - 1;
      }
  
      wp->w_tagstacklen++;
      tagstack[idx].tagname = tagname;
      tagstack[idx].cur_fnum = cur_fnum;
      tagstack[idx].cur_match = cur_match;
      if (tagstack[idx].cur_match < 0)
  	tagstack[idx].cur_match = 0;
      tagstack[idx].fmark.mark = mark;
      tagstack[idx].fmark.fnum = fnum;
      tagstack[idx].user_data = user_data;
  }
  
  /*
   * Add a list of items to the tag stack in the specified window
   */
      static void
  tagstack_push_items(win_T *wp, list_T *l)
  {
      listitem_T	*li;
      dictitem_T	*di;
      dict_T	*itemdict;
      char_u	*tagname;
      pos_T	mark;
      int		fnum;
  
      // Add one entry at a time to the tag stack
      FOR_ALL_LIST_ITEMS(l, li)
      {
  	if (li->li_tv.v_type != VAR_DICT || li->li_tv.vval.v_dict == NULL)
  	    continue;				// Skip non-dict items
  	itemdict = li->li_tv.vval.v_dict;
  
  	// parse 'from' for the cursor position before the tag jump
  	if ((di = dict_find(itemdict, (char_u *)"from", -1)) == NULL)
  	    continue;
  	if (list2fpos(&di->di_tv, &mark, &fnum, NULL, FALSE) != OK)
  	    continue;
  	if ((tagname =
  		dict_get_string(itemdict, (char_u *)"tagname", TRUE)) == NULL)
  	    continue;
  
  	if (mark.col > 0)
  	    mark.col--;
  	tagstack_push_item(wp, tagname,
  		(int)dict_get_number(itemdict, (char_u *)"bufnr"),
  		(int)dict_get_number(itemdict, (char_u *)"matchnr") - 1,
  		mark, fnum,
  		dict_get_string(itemdict, (char_u *)"user_data", TRUE));
      }
  }
  
  /*
   * Set the current index in the tag stack. Valid values are between 0
   * and the stack length (inclusive).
   */
      static void
  tagstack_set_curidx(win_T *wp, int curidx)
  {
      wp->w_tagstackidx = curidx;
      if (wp->w_tagstackidx < 0)			// sanity check
  	wp->w_tagstackidx = 0;
      if (wp->w_tagstackidx > wp->w_tagstacklen)
  	wp->w_tagstackidx = wp->w_tagstacklen;
  }
  
  /*
   * Set the tag stack entries of the specified window.
   * 'action' is set to one of:
   *	'a' for append
   *	'r' for replace
   *	't' for truncate
   */
      int
  set_tagstack(win_T *wp, dict_T *d, int action)
  {
      dictitem_T	*di;
      list_T	*l = NULL;
  
  #ifdef FEAT_EVAL
      // not allowed to alter the tag stack entries from inside tagfunc
      if (tfu_in_use)
      {
  	emsg(_(e_cannot_modify_tag_stack_within_tagfunc));
  	return FAIL;
      }
  #endif
  
      if ((di = dict_find(d, (char_u *)"items", -1)) != NULL)
      {
  	if (di->di_tv.v_type != VAR_LIST)
  	{
  	    emsg(_(e_list_required));
  	    return FAIL;
  	}
  	l = di->di_tv.vval.v_list;
      }
  
      if ((di = dict_find(d, (char_u *)"curidx", -1)) != NULL)
  	tagstack_set_curidx(wp, (int)tv_get_number(&di->di_tv) - 1);
  
      if (action == 't')		    // truncate the stack
      {
  	taggy_T	*tagstack = wp->w_tagstack;
  	int	tagstackidx = wp->w_tagstackidx;
  	int	tagstacklen = wp->w_tagstacklen;
  
  	// delete all the tag stack entries above the current entry
  	while (tagstackidx < tagstacklen)
  	    tagstack_clear_entry(&tagstack[--tagstacklen]);
  	wp->w_tagstacklen = tagstacklen;
      }
  
      if (l != NULL)
      {
  	if (action == 'r')		// replace the stack
  	    tagstack_clear(wp);
  
  	tagstack_push_items(wp, l);
  	// set the current index after the last entry
  	wp->w_tagstackidx = wp->w_tagstacklen;
      }
  
      return OK;
  }
  #endif
  