patch 8.1.1886: command line expansion code is spread outv8.1.1886

Problem:    Command line expansion code is spread out.
Solution:   Move the code to cmdexpand.c. (Yegappan Lakshmanan, closes #4831)

1 files changed, 2031 insertions, 0 deletions

diff --git a/src/cmdexpand.c b/src/cmdexpand.c
new file mode 100644
index 0000000000..c347c1aba8
--- /dev/null
+++ b/src/cmdexpand.c
@@ -0,0 +1,2031 @@
+/* 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.
+ */
+
+/*
+ * cmdexpand.c: functions for command-line completion
+ */
+
+#include "vim.h"
+
+static int	cmd_showtail;	// Only show path tail in lists ?
+
+static void	set_expand_context(expand_T *xp);
+static int	ExpandFromContext(expand_T *xp, char_u *, int *, char_u ***, int);
+static int	expand_showtail(expand_T *xp);
+#ifdef FEAT_CMDL_COMPL
+static int	expand_shellcmd(char_u *filepat, int *num_file, char_u ***file, int flagsarg);
+static int	ExpandRTDir(char_u *pat, int flags, int *num_file, char_u ***file, char *dirname[]);
+static int	ExpandPackAddDir(char_u *pat, int *num_file, char_u ***file);
+# if defined(FEAT_EVAL)
+static int	ExpandUserDefined(expand_T *xp, regmatch_T *regmatch, int *num_file, char_u ***file);
+static int	ExpandUserList(expand_T *xp, int *num_file, char_u ***file);
+# endif
+#endif
+
+#if defined(FEAT_CMDL_COMPL) || defined(PROTO)
+    static int
+sort_func_compare(const void *s1, const void *s2)
+{
+    char_u *p1 = *(char_u **)s1;
+    char_u *p2 = *(char_u **)s2;
+
+    if (*p1 != '<' && *p2 == '<') return -1;
+    if (*p1 == '<' && *p2 != '<') return 1;
+    return STRCMP(p1, p2);
+}
+#endif
+
+    static void
+ExpandEscape(
+    expand_T	*xp,
+    char_u	*str,
+    int		numfiles,
+    char_u	**files,
+    int		options)
+{
+    int		i;
+    char_u	*p;
+
+    // May change home directory back to "~"
+    if (options & WILD_HOME_REPLACE)
+	tilde_replace(str, numfiles, files);
+
+    if (options & WILD_ESCAPE)
+    {
+	if (xp->xp_context == EXPAND_FILES
+		|| xp->xp_context == EXPAND_FILES_IN_PATH
+		|| xp->xp_context == EXPAND_SHELLCMD
+		|| xp->xp_context == EXPAND_BUFFERS
+		|| xp->xp_context == EXPAND_DIRECTORIES)
+	{
+	    // Insert a backslash into a file name before a space, \, %, #
+	    // and wildmatch characters, except '~'.
+	    for (i = 0; i < numfiles; ++i)
+	    {
+		// for ":set path=" we need to escape spaces twice
+		if (xp->xp_backslash == XP_BS_THREE)
+		{
+		    p = vim_strsave_escaped(files[i], (char_u *)" ");
+		    if (p != NULL)
+		    {
+			vim_free(files[i]);
+			files[i] = p;
+#if defined(BACKSLASH_IN_FILENAME)
+			p = vim_strsave_escaped(files[i], (char_u *)" ");
+			if (p != NULL)
+			{
+			    vim_free(files[i]);
+			    files[i] = p;
+			}
+#endif
+		    }
+		}
+#ifdef BACKSLASH_IN_FILENAME
+		p = vim_strsave_fnameescape(files[i], FALSE);
+#else
+		p = vim_strsave_fnameescape(files[i], xp->xp_shell);
+#endif
+		if (p != NULL)
+		{
+		    vim_free(files[i]);
+		    files[i] = p;
+		}
+
+		// If 'str' starts with "\~", replace "~" at start of
+		// files[i] with "\~".
+		if (str[0] == '\\' && str[1] == '~' && files[i][0] == '~')
+		    escape_fname(&files[i]);
+	    }
+	    xp->xp_backslash = XP_BS_NONE;
+
+	    // If the first file starts with a '+' escape it.  Otherwise it
+	    // could be seen as "+cmd".
+	    if (*files[0] == '+')
+		escape_fname(&files[0]);
+	}
+	else if (xp->xp_context == EXPAND_TAGS)
+	{
+	    // Insert a backslash before characters in a tag name that
+	    // would terminate the ":tag" command.
+	    for (i = 0; i < numfiles; ++i)
+	    {
+		p = vim_strsave_escaped(files[i], (char_u *)"\\|\"");
+		if (p != NULL)
+		{
+		    vim_free(files[i]);
+		    files[i] = p;
+		}
+	    }
+	}
+    }
+}
+
+/*
+ * Return FAIL if this is not an appropriate context in which to do
+ * completion of anything, return OK if it is (even if there are no matches).
+ * For the caller, this means that the character is just passed through like a
+ * normal character (instead of being expanded).  This allows :s/^I^D etc.
+ */
+    int
+nextwild(
+    expand_T	*xp,
+    int		type,
+    int		options,	// extra options for ExpandOne()
+    int		escape)		// if TRUE, escape the returned matches
+{
+    cmdline_info_T	*ccline = get_cmdline_info();
+    int		i, j;
+    char_u	*p1;
+    char_u	*p2;
+    int		difflen;
+    int		v;
+
+    if (xp->xp_numfiles == -1)
+    {
+	set_expand_context(xp);
+	cmd_showtail = expand_showtail(xp);
+    }
+
+    if (xp->xp_context == EXPAND_UNSUCCESSFUL)
+    {
+	beep_flush();
+	return OK;  // Something illegal on command line
+    }
+    if (xp->xp_context == EXPAND_NOTHING)
+    {
+	// Caller can use the character as a normal char instead
+	return FAIL;
+    }
+
+    msg_puts("...");	    // show that we are busy
+    out_flush();
+
+    i = (int)(xp->xp_pattern - ccline->cmdbuff);
+    xp->xp_pattern_len = ccline->cmdpos - i;
+
+    if (type == WILD_NEXT || type == WILD_PREV)
+    {
+	// Get next/previous match for a previous expanded pattern.
+	p2 = ExpandOne(xp, NULL, NULL, 0, type);
+    }
+    else
+    {
+	// Translate string into pattern and expand it.
+	if ((p1 = addstar(xp->xp_pattern, xp->xp_pattern_len,
+						     xp->xp_context)) == NULL)
+	    p2 = NULL;
+	else
+	{
+	    int use_options = options |
+		    WILD_HOME_REPLACE|WILD_ADD_SLASH|WILD_SILENT;
+	    if (escape)
+		use_options |= WILD_ESCAPE;
+
+	    if (p_wic)
+		use_options += WILD_ICASE;
+	    p2 = ExpandOne(xp, p1,
+			 vim_strnsave(&ccline->cmdbuff[i], xp->xp_pattern_len),
+							   use_options, type);
+	    vim_free(p1);
+	    // longest match: make sure it is not shorter, happens with :help
+	    if (p2 != NULL && type == WILD_LONGEST)
+	    {
+		for (j = 0; j < xp->xp_pattern_len; ++j)
+		     if (ccline->cmdbuff[i + j] == '*'
+			     || ccline->cmdbuff[i + j] == '?')
+			 break;
+		if ((int)STRLEN(p2) < j)
+		    VIM_CLEAR(p2);
+	    }
+	}
+    }
+
+    if (p2 != NULL && !got_int)
+    {
+	difflen = (int)STRLEN(p2) - xp->xp_pattern_len;
+	if (ccline->cmdlen + difflen + 4 > ccline->cmdbufflen)
+	{
+	    v = realloc_cmdbuff(ccline->cmdlen + difflen + 4);
+	    xp->xp_pattern = ccline->cmdbuff + i;
+	}
+	else
+	    v = OK;
+	if (v == OK)
+	{
+	    mch_memmove(&ccline->cmdbuff[ccline->cmdpos + difflen],
+		    &ccline->cmdbuff[ccline->cmdpos],
+		    (size_t)(ccline->cmdlen - ccline->cmdpos + 1));
+	    mch_memmove(&ccline->cmdbuff[i], p2, STRLEN(p2));
+	    ccline->cmdlen += difflen;
+	    ccline->cmdpos += difflen;
+	}
+    }
+    vim_free(p2);
+
+    redrawcmd();
+    cursorcmd();
+
+    // When expanding a ":map" command and no matches are found, assume that
+    // the key is supposed to be inserted literally
+    if (xp->xp_context == EXPAND_MAPPINGS && p2 == NULL)
+	return FAIL;
+
+    if (xp->xp_numfiles <= 0 && p2 == NULL)
+	beep_flush();
+    else if (xp->xp_numfiles == 1)
+	// free expanded pattern
+	(void)ExpandOne(xp, NULL, NULL, 0, WILD_FREE);
+
+    return OK;
+}
+
+/*
+ * Do wildcard expansion on the string 'str'.
+ * Chars that should not be expanded must be preceded with a backslash.
+ * Return a pointer to allocated memory containing the new string.
+ * Return NULL for failure.
+ *
+ * "orig" is the originally expanded string, copied to allocated memory.  It
+ * should either be kept in orig_save or freed.  When "mode" is WILD_NEXT or
+ * WILD_PREV "orig" should be NULL.
+ *
+ * Results are cached in xp->xp_files and xp->xp_numfiles, except when "mode"
+ * is WILD_EXPAND_FREE or WILD_ALL.
+ *
+ * mode = WILD_FREE:	    just free previously expanded matches
+ * mode = WILD_EXPAND_FREE: normal expansion, do not keep matches
+ * mode = WILD_EXPAND_KEEP: normal expansion, keep matches
+ * mode = WILD_NEXT:	    use next match in multiple match, wrap to first
+ * mode = WILD_PREV:	    use previous match in multiple match, wrap to first
+ * mode = WILD_ALL:	    return all matches concatenated
+ * mode = WILD_LONGEST:	    return longest matched part
+ * mode = WILD_ALL_KEEP:    get all matches, keep matches
+ *
+ * options = WILD_LIST_NOTFOUND:    list entries without a match
+ * options = WILD_HOME_REPLACE:	    do home_replace() for buffer names
+ * options = WILD_USE_NL:	    Use '\n' for WILD_ALL
+ * options = WILD_NO_BEEP:	    Don't beep for multiple matches
+ * options = WILD_ADD_SLASH:	    add a slash after directory names
+ * options = WILD_KEEP_ALL:	    don't remove 'wildignore' entries
+ * options = WILD_SILENT:	    don't print warning messages
+ * options = WILD_ESCAPE:	    put backslash before special chars
+ * options = WILD_ICASE:	    ignore case for files
+ *
+ * The variables xp->xp_context and xp->xp_backslash must have been set!
+ */
+    char_u *
+ExpandOne(
+    expand_T	*xp,
+    char_u	*str,
+    char_u	*orig,	    // allocated copy of original of expanded string
+    int		options,
+    int		mode)
+{
+    char_u	*ss = NULL;
+    static int	findex;
+    static char_u *orig_save = NULL;	// kept value of orig
+    int		orig_saved = FALSE;
+    int		i;
+    long_u	len;
+    int		non_suf_match;		// number without matching suffix
+
+    // first handle the case of using an old match
+    if (mode == WILD_NEXT || mode == WILD_PREV)
+    {
+	if (xp->xp_numfiles > 0)
+	{
+	    if (mode == WILD_PREV)
+	    {
+		if (findex == -1)
+		    findex = xp->xp_numfiles;
+		--findex;
+	    }
+	    else    // mode == WILD_NEXT
+		++findex;
+
+	    // When wrapping around, return the original string, set findex to
+	    // -1.
+	    if (findex < 0)
+	    {
+		if (orig_save == NULL)
+		    findex = xp->xp_numfiles - 1;
+		else
+		    findex = -1;
+	    }
+	    if (findex >= xp->xp_numfiles)
+	    {
+		if (orig_save == NULL)
+		    findex = 0;
+		else
+		    findex = -1;
+	    }
+#ifdef FEAT_WILDMENU
+	    if (p_wmnu)
+		win_redr_status_matches(xp, xp->xp_numfiles, xp->xp_files,
+							findex, cmd_showtail);
+#endif
+	    if (findex == -1)
+		return vim_strsave(orig_save);
+	    return vim_strsave(xp->xp_files[findex]);
+	}
+	else
+	    return NULL;
+    }
+
+    // free old names
+    if (xp->xp_numfiles != -1 && mode != WILD_ALL && mode != WILD_LONGEST)
+    {
+	FreeWild(xp->xp_numfiles, xp->xp_files);
+	xp->xp_numfiles = -1;
+	VIM_CLEAR(orig_save);
+    }
+    findex = 0;
+
+    if (mode == WILD_FREE)	// only release file name
+	return NULL;
+
+    if (xp->xp_numfiles == -1)
+    {
+	vim_free(orig_save);
+	orig_save = orig;
+	orig_saved = TRUE;
+
+	// Do the expansion.
+	if (ExpandFromContext(xp, str, &xp->xp_numfiles, &xp->xp_files,
+							     options) == FAIL)
+	{
+#ifdef FNAME_ILLEGAL
+	    // Illegal file name has been silently skipped.  But when there
+	    // are wildcards, the real problem is that there was no match,
+	    // causing the pattern to be added, which has illegal characters.
+	    if (!(options & WILD_SILENT) && (options & WILD_LIST_NOTFOUND))
+		semsg(_(e_nomatch2), str);
+#endif
+	}
+	else if (xp->xp_numfiles == 0)
+	{
+	    if (!(options & WILD_SILENT))
+		semsg(_(e_nomatch2), str);
+	}
+	else
+	{
+	    // Escape the matches for use on the command line.
+	    ExpandEscape(xp, str, xp->xp_numfiles, xp->xp_files, options);
+
+	    // Check for matching suffixes in file names.
+	    if (mode != WILD_ALL && mode != WILD_ALL_KEEP
+						      && mode != WILD_LONGEST)
+	    {
+		if (xp->xp_numfiles)
+		    non_suf_match = xp->xp_numfiles;
+		else
+		    non_suf_match = 1;
+		if ((xp->xp_context == EXPAND_FILES
+			    || xp->xp_context == EXPAND_DIRECTORIES)
+			&& xp->xp_numfiles > 1)
+		{
+		    // More than one match; check suffix.
+		    // The files will have been sorted on matching suffix in
+		    // expand_wildcards, only need to check the first two.
+		    non_suf_match = 0;
+		    for (i = 0; i < 2; ++i)
+			if (match_suffix(xp->xp_files[i]))
+			    ++non_suf_match;
+		}
+		if (non_suf_match != 1)
+		{
+		    // Can we ever get here unless it's while expanding
+		    // interactively?  If not, we can get rid of this all
+		    // together. Don't really want to wait for this message
+		    // (and possibly have to hit return to continue!).
+		    if (!(options & WILD_SILENT))
+			emsg(_(e_toomany));
+		    else if (!(options & WILD_NO_BEEP))
+			beep_flush();
+		}
+		if (!(non_suf_match != 1 && mode == WILD_EXPAND_FREE))
+		    ss = vim_strsave(xp->xp_files[0]);
+	    }
+	}
+    }
+
+    // Find longest common part
+    if (mode == WILD_LONGEST && xp->xp_numfiles > 0)
+    {
+	int mb_len = 1;
+	int c0, ci;
+
+	for (len = 0; xp->xp_files[0][len]; len += mb_len)
+	{
+	    if (has_mbyte)
+	    {
+		mb_len = (*mb_ptr2len)(&xp->xp_files[0][len]);
+		c0 =(* mb_ptr2char)(&xp->xp_files[0][len]);
+	    }
+	    else
+		c0 = xp->xp_files[0][len];
+	    for (i = 1; i < xp->xp_numfiles; ++i)
+	    {
+		if (has_mbyte)
+		    ci =(* mb_ptr2char)(&xp->xp_files[i][len]);
+		else
+		    ci = xp->xp_files[i][len];
+		if (p_fic && (xp->xp_context == EXPAND_DIRECTORIES
+			|| xp->xp_context == EXPAND_FILES
+			|| xp->xp_context == EXPAND_SHELLCMD
+			|| xp->xp_context == EXPAND_BUFFERS))
+		{
+		    if (MB_TOLOWER(c0) != MB_TOLOWER(ci))
+			break;
+		}
+		else if (c0 != ci)
+		    break;
+	    }
+	    if (i < xp->xp_numfiles)
+	    {
+		if (!(options & WILD_NO_BEEP))
+		    vim_beep(BO_WILD);
+		break;
+	    }
+	}
+
+	ss = alloc(len + 1);
+	if (ss)
+	    vim_strncpy(ss, xp->xp_files[0], (size_t)len);
+	findex = -1;			    // next p_wc gets first one
+    }
+
+    // Concatenate all matching names
+    if (mode == WILD_ALL && xp->xp_numfiles > 0)
+    {
+	len = 0;
+	for (i = 0; i < xp->xp_numfiles; ++i)
+	    len += (long_u)STRLEN(xp->xp_files[i]) + 1;
+	ss = alloc(len);
+	if (ss != NULL)
+	{
+	    *ss = NUL;
+	    for (i = 0; i < xp->xp_numfiles; ++i)
+	    {
+		STRCAT(ss, xp->xp_files[i]);
+		if (i != xp->xp_numfiles - 1)
+		    STRCAT(ss, (options & WILD_USE_NL) ? "\n" : " ");
+	    }
+	}
+    }
+
+    if (mode == WILD_EXPAND_FREE || mode == WILD_ALL)
+	ExpandCleanup(xp);
+
+    // Free "orig" if it wasn't stored in "orig_save".
+    if (!orig_saved)
+	vim_free(orig);
+
+    return ss;
+}
+
+/*
+ * Prepare an expand structure for use.
+ */
+    void
+ExpandInit(expand_T *xp)
+{
+    xp->xp_pattern = NULL;
+    xp->xp_pattern_len = 0;
+    xp->xp_backslash = XP_BS_NONE;
+#ifndef BACKSLASH_IN_FILENAME
+    xp->xp_shell = FALSE;
+#endif
+    xp->xp_numfiles = -1;
+    xp->xp_files = NULL;
+#if defined(FEAT_EVAL) && defined(FEAT_CMDL_COMPL)
+    xp->xp_arg = NULL;
+#endif
+    xp->xp_line = NULL;
+}
+
+/*
+ * Cleanup an expand structure after use.
+ */
+    void
+ExpandCleanup(expand_T *xp)
+{
+    if (xp->xp_numfiles >= 0)
+    {
+	FreeWild(xp->xp_numfiles, xp->xp_files);
+	xp->xp_numfiles = -1;
+    }
+}
+
+/*
+ * Show all matches for completion on the command line.
+ * Returns EXPAND_NOTHING when the character that triggered expansion should
+ * be inserted like a normal character.
+ */
+    int
+showmatches(expand_T *xp, int wildmenu UNUSED)
+{
+    cmdline_info_T	*ccline = get_cmdline_info();
+#define L_SHOWFILE(m) (showtail ? sm_gettail(files_found[m]) : files_found[m])
+    int		num_files;
+    char_u	**files_found;
+    int		i, j, k;
+    int		maxlen;
+    int		lines;
+    int		columns;
+    char_u	*p;
+    int		lastlen;
+    int		attr;
+    int		showtail;
+
+    if (xp->xp_numfiles == -1)
+    {
+	set_expand_context(xp);
+	i = expand_cmdline(xp, ccline->cmdbuff, ccline->cmdpos,
+						    &num_files, &files_found);
+	showtail = expand_showtail(xp);
+	if (i != EXPAND_OK)
+	    return i;
+
+    }
+    else
+    {
+	num_files = xp->xp_numfiles;
+	files_found = xp->xp_files;
+	showtail = cmd_showtail;
+    }
+
+#ifdef FEAT_WILDMENU
+    if (!wildmenu)
+    {
+#endif
+	msg_didany = FALSE;		// lines_left will be set
+	msg_start();			// prepare for paging
+	msg_putchar('\n');
+	out_flush();
+	cmdline_row = msg_row;
+	msg_didany = FALSE;		// lines_left will be set again
+	msg_start();			// prepare for paging
+#ifdef FEAT_WILDMENU
+    }
+#endif
+
+    if (got_int)
+	got_int = FALSE;	// only int. the completion, not the cmd line
+#ifdef FEAT_WILDMENU
+    else if (wildmenu)
+	win_redr_status_matches(xp, num_files, files_found, -1, showtail);
+#endif
+    else
+    {
+	// find the length of the longest file name
+	maxlen = 0;
+	for (i = 0; i < num_files; ++i)
+	{
+	    if (!showtail && (xp->xp_context == EXPAND_FILES
+			  || xp->xp_context == EXPAND_SHELLCMD
+			  || xp->xp_context == EXPAND_BUFFERS))
+	    {
+		home_replace(NULL, files_found[i], NameBuff, MAXPATHL, TRUE);
+		j = vim_strsize(NameBuff);
+	    }
+	    else
+		j = vim_strsize(L_SHOWFILE(i));
+	    if (j > maxlen)
+		maxlen = j;
+	}
+
+	if (xp->xp_context == EXPAND_TAGS_LISTFILES)
+	    lines = num_files;
+	else
+	{
+	    // compute the number of columns and lines for the listing
+	    maxlen += 2;    // two spaces between file names
+	    columns = ((int)Columns + 2) / maxlen;
+	    if (columns < 1)
+		columns = 1;
+	    lines = (num_files + columns - 1) / columns;
+	}
+
+	attr = HL_ATTR(HLF_D);	// find out highlighting for directories
+
+	if (xp->xp_context == EXPAND_TAGS_LISTFILES)
+	{
+	    msg_puts_attr(_("tagname"), HL_ATTR(HLF_T));
+	    msg_clr_eos();
+	    msg_advance(maxlen - 3);
+	    msg_puts_attr(_(" kind file\n"), HL_ATTR(HLF_T));
+	}
+
+	// list the files line by line
+	for (i = 0; i < lines; ++i)
+	{
+	    lastlen = 999;
+	    for (k = i; k < num_files; k += lines)
+	    {
+		if (xp->xp_context == EXPAND_TAGS_LISTFILES)
+		{
+		    msg_outtrans_attr(files_found[k], HL_ATTR(HLF_D));
+		    p = files_found[k] + STRLEN(files_found[k]) + 1;
+		    msg_advance(maxlen + 1);
+		    msg_puts((char *)p);
+		    msg_advance(maxlen + 3);
+		    msg_outtrans_long_attr(p + 2, HL_ATTR(HLF_D));
+		    break;
+		}
+		for (j = maxlen - lastlen; --j >= 0; )
+		    msg_putchar(' ');
+		if (xp->xp_context == EXPAND_FILES
+					  || xp->xp_context == EXPAND_SHELLCMD
+					  || xp->xp_context == EXPAND_BUFFERS)
+		{
+		    // highlight directories
+		    if (xp->xp_numfiles != -1)
+		    {
+			char_u	*halved_slash;
+			char_u	*exp_path;
+
+			// Expansion was done before and special characters
+			// were escaped, need to halve backslashes.  Also
+			// $HOME has been replaced with ~/.
+			exp_path = expand_env_save_opt(files_found[k], TRUE);
+			halved_slash = backslash_halve_save(
+				exp_path != NULL ? exp_path : files_found[k]);
+			j = mch_isdir(halved_slash != NULL ? halved_slash
+							    : files_found[k]);
+			vim_free(exp_path);
+			vim_free(halved_slash);
+		    }
+		    else
+			// Expansion was done here, file names are literal.
+			j = mch_isdir(files_found[k]);
+		    if (showtail)
+			p = L_SHOWFILE(k);
+		    else
+		    {
+			home_replace(NULL, files_found[k], NameBuff, MAXPATHL,
+									TRUE);
+			p = NameBuff;
+		    }
+		}
+		else
+		{
+		    j = FALSE;
+		    p = L_SHOWFILE(k);
+		}
+		lastlen = msg_outtrans_attr(p, j ? attr : 0);
+	    }
+	    if (msg_col > 0)	// when not wrapped around
+	    {
+		msg_clr_eos();
+		msg_putchar('\n');
+	    }
+	    out_flush();		    // show one line at a time
+	    if (got_int)
+	    {
+		got_int = FALSE;
+		break;
+	    }
+	}
+
+	// we redraw the command below the lines that we have just listed
+	// This is a bit tricky, but it saves a lot of screen updating.
+	cmdline_row = msg_row;	// will put it back later
+    }
+
+    if (xp->xp_numfiles == -1)
+	FreeWild(num_files, files_found);
+
+    return EXPAND_OK;
+}
+
+/*
+ * Private gettail for showmatches() (and win_redr_status_matches()):
+ * Find tail of file name path, but ignore trailing "/".
+ */
+    char_u *
+sm_gettail(char_u *s)
+{
+    char_u	*p;
+    char_u	*t = s;
+    int		had_sep = FALSE;
+
+    for (p = s; *p != NUL; )
+    {
+	if (vim_ispathsep(*p)
+#ifdef BACKSLASH_IN_FILENAME
+		&& !rem_backslash(p)
+#endif
+	   )
+	    had_sep = TRUE;
+	else if (had_sep)
+	{
+	    t = p;
+	    had_sep = FALSE;
+	}
+	MB_PTR_ADV(p);
+    }
+    return t;
+}
+
+/*
+ * Return TRUE if we only need to show the tail of completion matches.
+ * When not completing file names or there is a wildcard in the path FALSE is
+ * returned.
+ */
+    static int
+expand_showtail(expand_T *xp)
+{
+    char_u	*s;
+    char_u	*end;
+
+    // When not completing file names a "/" may mean something different.
+    if (xp->xp_context != EXPAND_FILES
+	    && xp->xp_context != EXPAND_SHELLCMD
+	    && xp->xp_context != EXPAND_DIRECTORIES)
+	return FALSE;
+
+    end = gettail(xp->xp_pattern);
+    if (end == xp->xp_pattern)		// there is no path separator
+	return FALSE;
+
+    for (s = xp->xp_pattern; s < end; s++)
+    {
+	// Skip escaped wildcards.  Only when the backslash is not a path
+	// separator, on DOS the '*' "path\*\file" must not be skipped.
+	if (rem_backslash(s))
+	    ++s;
+	else if (vim_strchr((char_u *)"*?[", *s) != NULL)
+	    return FALSE;
+    }
+    return TRUE;
+}
+
+/*
+ * Prepare a string for expansion.
+ * When expanding file names: The string will be used with expand_wildcards().
+ * Copy "fname[len]" into allocated memory and add a '*' at the end.
+ * When expanding other names: The string will be used with regcomp().  Copy
+ * the name into allocated memory and prepend "^".
+ */
+    char_u *
+addstar(
+    char_u	*fname,
+    int		len,
+    int		context)	// EXPAND_FILES etc.
+{
+    char_u	*retval;
+    int		i, j;
+    int		new_len;
+    char_u	*tail;
+    int		ends_in_star;
+
+    if (context != EXPAND_FILES
+	    && context != EXPAND_FILES_IN_PATH
+	    && context != EXPAND_SHELLCMD
+	    && context != EXPAND_DIRECTORIES)
+    {
+	// Matching will be done internally (on something other than files).
+	// So we convert the file-matching-type wildcards into our kind for
+	// use with vim_regcomp().  First work out how long it will be:
+
+	// For help tags the translation is done in find_help_tags().
+	// For a tag pattern starting with "/" no translation is needed.
+	if (context == EXPAND_HELP
+		|| context == EXPAND_COLORS
+		|| context == EXPAND_COMPILER
+		|| context == EXPAND_OWNSYNTAX
+		|| context == EXPAND_FILETYPE
+		|| context == EXPAND_PACKADD
+		|| ((context == EXPAND_TAGS_LISTFILES
+			|| context == EXPAND_TAGS)
+		    && fname[0] == '/'))
+	    retval = vim_strnsave(fname, len);
+	else
+	{
+	    new_len = len + 2;		// +2 for '^' at start, NUL at end
+	    for (i = 0; i < len; i++)
+	    {
+		if (fname[i] == '*' || fname[i] == '~')
+		    new_len++;		// '*' needs to be replaced by ".*"
+					// '~' needs to be replaced by "\~"
+
+		// Buffer names are like file names.  "." should be literal
+		if (context == EXPAND_BUFFERS && fname[i] == '.')
+		    new_len++;		// "." becomes "\."
+
+		// Custom expansion takes care of special things, match
+		// backslashes literally (perhaps also for other types?)
+		if ((context == EXPAND_USER_DEFINED
+			  || context == EXPAND_USER_LIST) && fname[i] == '\\')
+		    new_len++;		// '\' becomes "\\"
+	    }
+	    retval = alloc(new_len);
+	    if (retval != NULL)
+	    {
+		retval[0] = '^';
+		j = 1;
+		for (i = 0; i < len; i++, j++)
+		{
+		    // Skip backslash.  But why?  At least keep it for custom
+		    // expansion.
+		    if (context != EXPAND_USER_DEFINED
+			    && context != EXPAND_USER_LIST
+			    && fname[i] == '\\'
+			    && ++i == len)
+			break;
+
+		    switch (fname[i])
+		    {
+			case '*':   retval[j++] = '.';
+				    break;
+			case '~':   retval[j++] = '\\';
+				    break;
+			case '?':   retval[j] = '.';
+				    continue;
+			case '.':   if (context == EXPAND_BUFFERS)
+					retval[j++] = '\\';
+				    break;
+			case '\\':  if (context == EXPAND_USER_DEFINED
+					    || context == EXPAND_USER_LIST)
+					retval[j++] = '\\';
+				    break;
+		    }
+		    retval[j] = fname[i];
+		}
+		retval[j] = NUL;
+	    }
+	}
+    }
+    else
+    {
+	retval = alloc(len + 4);
+	if (retval != NULL)
+	{
+	    vim_strncpy(retval, fname, len);
+
+	    // Don't add a star to *, ~, ~user, $var or `cmd`.
+	    // * would become **, which walks the whole tree.
+	    // ~ would be at the start of the file name, but not the tail.
+	    // $ could be anywhere in the tail.
+	    // ` could be anywhere in the file name.
+	    // When the name ends in '$' don't add a star, remove the '$'.
+	    tail = gettail(retval);
+	    ends_in_star = (len > 0 && retval[len - 1] == '*');
+#ifndef BACKSLASH_IN_FILENAME
+	    for (i = len - 2; i >= 0; --i)
+	    {
+		if (retval[i] != '\\')
+		    break;
+		ends_in_star = !ends_in_star;
+	    }
+#endif
+	    if ((*retval != '~' || tail != retval)
+		    && !ends_in_star
+		    && vim_strchr(tail, '$') == NULL
+		    && vim_strchr(retval, '`') == NULL)
+		retval[len++] = '*';
+	    else if (len > 0 && retval[len - 1] == '$')
+		--len;
+	    retval[len] = NUL;
+	}
+    }
+    return retval;
+}
+
+/*
+ * Must parse the command line so far to work out what context we are in.
+ * Completion can then be done based on that context.
+ * This routine sets the variables:
+ *  xp->xp_pattern	    The start of the pattern to be expanded within
+ *				the command line (ends at the cursor).
+ *  xp->xp_context	    The type of thing to expand.  Will be one of:
+ *
+ *  EXPAND_UNSUCCESSFUL	    Used sometimes when there is something illegal on
+ *			    the command line, like an unknown command.	Caller
+ *			    should beep.
+ *  EXPAND_NOTHING	    Unrecognised context for completion, use char like
+ *			    a normal char, rather than for completion.	eg
+ *			    :s/^I/
+ *  EXPAND_COMMANDS	    Cursor is still touching the command, so complete
+ *			    it.
+ *  EXPAND_BUFFERS	    Complete file names for :buf and :sbuf commands.
+ *  EXPAND_FILES	    After command with EX_XFILE set, or after setting
+ *			    with P_EXPAND set.	eg :e ^I, :w>>^I
+ *  EXPAND_DIRECTORIES	    In some cases this is used instead of the latter
+ *			    when we know only directories are of interest.  eg
+ *			    :set dir=^I
+ *  EXPAND_SHELLCMD	    After ":!cmd", ":r !cmd"  or ":w !cmd".
+ *  EXPAND_SETTINGS	    Complete variable names.  eg :set d^I
+ *  EXPAND_BOOL_SETTINGS    Complete boolean variables only,  eg :set no^I
+ *  EXPAND_TAGS		    Complete tags from the files in p_tags.  eg :ta a^I
+ *  EXPAND_TAGS_LISTFILES   As above, but list filenames on ^D, after :tselect
+ *  EXPAND_HELP		    Complete tags from the file 'helpfile'/tags
+ *  EXPAND_EVENTS	    Complete event names
+ *  EXPAND_SYNTAX	    Complete :syntax command arguments
+ *  EXPAND_HIGHLIGHT	    Complete highlight (syntax) group names
+ *  EXPAND_AUGROUP	    Complete autocommand group names
+ *  EXPAND_USER_VARS	    Complete user defined variable names, eg :unlet a^I
+ *  EXPAND_MAPPINGS	    Complete mapping and abbreviation names,
+ *			      eg :unmap a^I , :cunab x^I
+ *  EXPAND_FUNCTIONS	    Complete internal or user defined function names,
+ *			      eg :call sub^I
+ *  EXPAND_USER_FUNC	    Complete user defined function names, eg :delf F^I
+ *  EXPAND_EXPRESSION	    Complete internal or user defined function/variable
+ *			    names in expressions, eg :while s^I
+ *  EXPAND_ENV_VARS	    Complete environment variable names
+ *  EXPAND_USER		    Complete user names
+ */
+    static void
+set_expand_context(expand_T *xp)
+{
+    cmdline_info_T	*ccline = get_cmdline_info();
+
+    // only expansion for ':', '>' and '=' command-lines
+    if (ccline->cmdfirstc != ':'
+#ifdef FEAT_EVAL
+	    && ccline->cmdfirstc != '>' && ccline->cmdfirstc != '='
+	    && !ccline->input_fn
+#endif
+	    )
+    {
+	xp->xp_context = EXPAND_NOTHING;
+	return;
+    }
+    set_cmd_context(xp, ccline->cmdbuff, ccline->cmdlen, ccline->cmdpos, TRUE);
+}
+
+    void
+set_cmd_context(
+    expand_T	*xp,
+    char_u	*str,	    // start of command line
+    int		len,	    // length of command line (excl. NUL)
+    int		col,	    // position of cursor
+    int		use_ccline UNUSED) // use ccline for info
+{
+#ifdef FEAT_EVAL
+    cmdline_info_T	*ccline = get_cmdline_info();
+#endif
+    int		old_char = NUL;
+    char_u	*nextcomm;
+
+    // Avoid a UMR warning from Purify, only save the character if it has been
+    // written before.
+    if (col < len)
+	old_char = str[col];
+    str[col] = NUL;
+    nextcomm = str;
+
+#ifdef FEAT_EVAL
+    if (use_ccline && ccline->cmdfirstc == '=')
+    {
+# ifdef FEAT_CMDL_COMPL
+	// pass CMD_SIZE because there is no real command
+	set_context_for_expression(xp, str, CMD_SIZE);
+# endif
+    }
+    else if (use_ccline && ccline->input_fn)
+    {
+	xp->xp_context = ccline->xp_context;
+	xp->xp_pattern = ccline->cmdbuff;
+# if defined(FEAT_CMDL_COMPL)
+	xp->xp_arg = ccline->xp_arg;
+# endif
+    }
+    else
+#endif
+	while (nextcomm != NULL)
+	    nextcomm = set_one_cmd_context(xp, nextcomm);
+
+    // Store the string here so that call_user_expand_func() can get to them
+    // easily.
+    xp->xp_line = str;
+    xp->xp_col = col;
+
+    str[col] = old_char;
+}
+
+/*
+ * Expand the command line "str" from context "xp".
+ * "xp" must have been set by set_cmd_context().
+ * xp->xp_pattern points into "str", to where the text that is to be expanded
+ * starts.
+ * Returns EXPAND_UNSUCCESSFUL when there is something illegal before the
+ * cursor.
+ * Returns EXPAND_NOTHING when there is nothing to expand, might insert the
+ * key that triggered expansion literally.
+ * Returns EXPAND_OK otherwise.
+ */
+    int
+expand_cmdline(
+    expand_T	*xp,
+    char_u	*str,		// start of command line
+    int		col,		// position of cursor
+    int		*matchcount,	// return: nr of matches
+    char_u	***matches)	// return: array of pointers to matches
+{
+    char_u	*file_str = NULL;
+    int		options = WILD_ADD_SLASH|WILD_SILENT;
+
+    if (xp->xp_context == EXPAND_UNSUCCESSFUL)
+    {
+	beep_flush();
+	return EXPAND_UNSUCCESSFUL;  // Something illegal on command line
+    }
+    if (xp->xp_context == EXPAND_NOTHING)
+    {
+	// Caller can use the character as a normal char instead
+	return EXPAND_NOTHING;
+    }
+
+    // add star to file name, or convert to regexp if not exp. files.
+    xp->xp_pattern_len = (int)(str + col - xp->xp_pattern);
+    file_str = addstar(xp->xp_pattern, xp->xp_pattern_len, xp->xp_context);
+    if (file_str == NULL)
+	return EXPAND_UNSUCCESSFUL;
+
+    if (p_wic)
+	options += WILD_ICASE;
+
+    // find all files that match the description
+    if (ExpandFromContext(xp, file_str, matchcount, matches, options) == FAIL)
+    {
+	*matchcount = 0;
+	*matches = NULL;
+    }
+    vim_free(file_str);
+
+    return EXPAND_OK;
+}
+
+#ifdef FEAT_MULTI_LANG
+/*
+ * Cleanup matches for help tags:
+ * Remove "@ab" if the top of 'helplang' is "ab" and the language of the first
+ * tag matches it.  Otherwise remove "@en" if "en" is the only language.
+ */
+    static void
+cleanup_help_tags(int num_file, char_u **file)
+{
+    int		i, j;
+    int		len;
+    char_u	buf[4];
+    char_u	*p = buf;
+
+    if (p_hlg[0] != NUL && (p_hlg[0] != 'e' || p_hlg[1] != 'n'))
+    {
+	*p++ = '@';
+	*p++ = p_hlg[0];
+	*p++ = p_hlg[1];
+    }
+    *p = NUL;
+
+    for (i = 0; i < num_file; ++i)
+    {
+	len = (int)STRLEN(file[i]) - 3;
+	if (len <= 0)
+	    continue;
+	if (STRCMP(file[i] + len, "@en") == 0)
+	{
+	    // Sorting on priority means the same item in another language may
+	    // be anywhere.  Search all items for a match up to the "@en".
+	    for (j = 0; j < num_file; ++j)
+		if (j != i && (int)STRLEN(file[j]) == len + 3
+			   && STRNCMP(file[i], file[j], len + 1) == 0)
+		    break;
+	    if (j == num_file)
+		// item only exists with @en, remove it
+		file[i][len] = NUL;
+	}
+    }
+
+    if (*buf != NUL)
+	for (i = 0; i < num_file; ++i)
+	{
+	    len = (int)STRLEN(file[i]) - 3;
+	    if (len <= 0)
+		continue;
+	    if (STRCMP(file[i] + len, buf) == 0)
+	    {
+		// remove the default language
+		file[i][len] = NUL;
+	    }
+	}
+}
+#endif
+
+/*
+ * Do the expansion based on xp->xp_context and "pat".
+ */
+    static int
+ExpandFromContext(
+    expand_T	*xp,
+    char_u	*pat,
+    int		*num_file,
+    char_u	***file,
+    int		options)  // WILD_ flags
+{
+#ifdef FEAT_CMDL_COMPL
+    regmatch_T	regmatch;
+#endif
+    int		ret;
+    int		flags;
+
+    flags = EW_DIR;	// include directories
+    if (options & WILD_LIST_NOTFOUND)
+	flags |= EW_NOTFOUND;
+    if (options & WILD_ADD_SLASH)
+	flags |= EW_ADDSLASH;
+    if (options & WILD_KEEP_ALL)
+	flags |= EW_KEEPALL;
+    if (options & WILD_SILENT)
+	flags |= EW_SILENT;
+    if (options & WILD_ALLLINKS)
+	flags |= EW_ALLLINKS;
+
+    if (xp->xp_context == EXPAND_FILES
+	    || xp->xp_context == EXPAND_DIRECTORIES
+	    || xp->xp_context == EXPAND_FILES_IN_PATH)
+    {
+	// Expa