new file mode 100644
--- /dev/null
+++ b/src/cmdhist.c
@@ -0,0 +1,762 @@
+/* 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.
+ */
+
+/*
+ * cmdhist.c: Functions for the history of the command-line.
+ */
+
+#include "vim.h"
+
+static histentry_T *(history[HIST_COUNT]) = {NULL, NULL, NULL, NULL, NULL};
+static int	hisidx[HIST_COUNT] = {-1, -1, -1, -1, -1};  // lastused entry
+static int	hisnum[HIST_COUNT] = {0, 0, 0, 0, 0};
+		    // identifying (unique) number of newest history entry
+static int	hislen = 0;		// actual length of history tables
+
+/*
+ * Return the length of the history tables
+ */
+    int
+get_hislen(void)
+{
+    return hislen;
+}
+
+/*
+ * Return a pointer to a specified history table
+ */
+    histentry_T *
+get_histentry(int hist_type)
+{
+    return history[hist_type];
+}
+
+    void
+set_histentry(int hist_type, histentry_T *entry)
+{
+    history[hist_type] = entry;
+}
+
+    int *
+get_hisidx(int hist_type)
+{
+    return &hisidx[hist_type];
+}
+
+    int *
+get_hisnum(int hist_type)
+{
+    return &hisnum[hist_type];
+}
+
+/*
+ * Translate a history character to the associated type number.
+ */
+    int
+hist_char2type(int c)
+{
+    if (c == ':')
+	return HIST_CMD;
+    if (c == '=')
+	return HIST_EXPR;
+    if (c == '@')
+	return HIST_INPUT;
+    if (c == '>')
+	return HIST_DEBUG;
+    return HIST_SEARCH;	    // must be '?' or '/'
+}
+
+/*
+ * Table of history names.
+ * These names are used in :history and various hist...() functions.
+ * It is sufficient to give the significant prefix of a history name.
+ */
+
+static char *(history_names[]) =
+{
+    "cmd",
+    "search",
+    "expr",
+    "input",
+    "debug",
+    NULL
+};
+
+#if defined(FEAT_CMDL_COMPL) || defined(PROTO)
+/*
+ * Function given to ExpandGeneric() to obtain the possible first
+ * arguments of the ":history command.
+ */
+    char_u *
+get_history_arg(expand_T *xp UNUSED, int idx)
+{
+    static char_u compl[2] = { NUL, NUL };
+    char *short_names = ":=@>?/";
+    int short_names_count = (int)STRLEN(short_names);
+    int history_name_count = sizeof(history_names) / sizeof(char *) - 1;
+
+    if (idx < short_names_count)
+    {
+	compl[0] = (char_u)short_names[idx];
+	return compl;
+    }
+    if (idx < short_names_count + history_name_count)
+	return (char_u *)history_names[idx - short_names_count];
+    if (idx == short_names_count + history_name_count)
+	return (char_u *)"all";
+    return NULL;
+}
+#endif
+
+/*
+ * init_history() - Initialize the command line history.
+ * Also used to re-allocate the history when the size changes.
+ */
+    void
+init_history(void)
+{
+    int		newlen;	    // new length of history table
+    histentry_T	*temp;
+    int		i;
+    int		j;
+    int		type;
+
+    // If size of history table changed, reallocate it
+    newlen = (int)p_hi;
+    if (newlen != hislen)			// history length changed
+    {
+	for (type = 0; type < HIST_COUNT; ++type)   // adjust the tables
+	{
+	    if (newlen)
+	    {
+		temp = ALLOC_MULT(histentry_T, newlen);
+		if (temp == NULL)   // out of memory!
+		{
+		    if (type == 0)  // first one: just keep the old length
+		    {
+			newlen = hislen;
+			break;
+		    }
+		    // Already changed one table, now we can only have zero
+		    // length for all tables.
+		    newlen = 0;
+		    type = -1;
+		    continue;
+		}
+	    }
+	    else
+		temp = NULL;
+	    if (newlen == 0 || temp != NULL)
+	    {
+		if (hisidx[type] < 0)		// there are no entries yet
+		{
+		    for (i = 0; i < newlen; ++i)
+			clear_hist_entry(&temp[i]);
+		}
+		else if (newlen > hislen)	// array becomes bigger
+		{
+		    for (i = 0; i <= hisidx[type]; ++i)
+			temp[i] = history[type][i];
+		    j = i;
+		    for ( ; i <= newlen - (hislen - hisidx[type]); ++i)
+			clear_hist_entry(&temp[i]);
+		    for ( ; j < hislen; ++i, ++j)
+			temp[i] = history[type][j];
+		}
+		else				// array becomes smaller or 0
+		{
+		    j = hisidx[type];
+		    for (i = newlen - 1; ; --i)
+		    {
+			if (i >= 0)		// copy newest entries
+			    temp[i] = history[type][j];
+			else			// remove older entries
+			    vim_free(history[type][j].hisstr);
+			if (--j < 0)
+			    j = hislen - 1;
+			if (j == hisidx[type])
+			    break;
+		    }
+		    hisidx[type] = newlen - 1;
+		}
+		vim_free(history[type]);
+		history[type] = temp;
+	    }
+	}
+	hislen = newlen;
+    }
+}
+
+    void
+clear_hist_entry(histentry_T *hisptr)
+{
+    hisptr->hisnum = 0;
+    hisptr->viminfo = FALSE;
+    hisptr->hisstr = NULL;
+    hisptr->time_set = 0;
+}
+
+/*
+ * Check if command line 'str' is already in history.
+ * If 'move_to_front' is TRUE, matching entry is moved to end of history.
+ */
+    int
+in_history(
+    int	    type,
+    char_u  *str,
+    int	    move_to_front,	// Move the entry to the front if it exists
+    int	    sep,
+    int	    writing)		// ignore entries read from viminfo
+{
+    int	    i;
+    int	    last_i = -1;
+    char_u  *p;
+
+    if (hisidx[type] < 0)
+	return FALSE;
+    i = hisidx[type];
+    do
+    {
+	if (history[type][i].hisstr == NULL)
+	    return FALSE;
+
+	// For search history, check that the separator character matches as
+	// well.
+	p = history[type][i].hisstr;
+	if (STRCMP(str, p) == 0
+		&& !(writing && history[type][i].viminfo)
+		&& (type != HIST_SEARCH || sep == p[STRLEN(p) + 1]))
+	{
+	    if (!move_to_front)
+		return TRUE;
+	    last_i = i;
+	    break;
+	}
+	if (--i < 0)
+	    i = hislen - 1;
+    } while (i != hisidx[type]);
+
+    if (last_i >= 0)
+    {
+	str = history[type][i].hisstr;
+	while (i != hisidx[type])
+	{
+	    if (++i >= hislen)
+		i = 0;
+	    history[type][last_i] = history[type][i];
+	    last_i = i;
+	}
+	history[type][i].hisnum = ++hisnum[type];
+	history[type][i].viminfo = FALSE;
+	history[type][i].hisstr = str;
+	history[type][i].time_set = vim_time();
+	return TRUE;
+    }
+    return FALSE;
+}
+
+/*
+ * Convert history name (from table above) to its HIST_ equivalent.
+ * When "name" is empty, return "cmd" history.
+ * Returns -1 for unknown history name.
+ */
+    static int
+get_histtype(char_u *name)
+{
+    int		i;
+    int		len = (int)STRLEN(name);
+
+    // No argument: use current history.
+    if (len == 0)
+	return hist_char2type(get_cmdline_firstc());
+
+    for (i = 0; history_names[i] != NULL; ++i)
+	if (STRNICMP(name, history_names[i], len) == 0)
+	    return i;
+
+    if (vim_strchr((char_u *)":=@>?/", name[0]) != NULL && name[1] == NUL)
+	return hist_char2type(name[0]);
+
+    return -1;
+}
+
+static int	last_maptick = -1;	// last seen maptick
+
+/*
+ * Add the given string to the given history.  If the string is already in the
+ * history then it is moved to the front.  "histype" may be one of he HIST_
+ * values.
+ */
+    void
+add_to_history(
+    int		histype,
+    char_u	*new_entry,
+    int		in_map,		// consider maptick when inside a mapping
+    int		sep)		// separator character used (search hist)
+{
+    histentry_T	*hisptr;
+    int		len;
+
+    if (hislen == 0)		// no history
+	return;
+
+    if (cmdmod.keeppatterns && histype == HIST_SEARCH)
+	return;
+
+    // Searches inside the same mapping overwrite each other, so that only
+    // the last line is kept.  Be careful not to remove a line that was moved
+    // down, only lines that were added.
+    if (histype == HIST_SEARCH && in_map)
+    {
+	if (maptick == last_maptick && hisidx[HIST_SEARCH] >= 0)
+	{
+	    // Current line is from the same mapping, remove it
+	    hisptr = &history[HIST_SEARCH][hisidx[HIST_SEARCH]];
+	    vim_free(hisptr->hisstr);
+	    clear_hist_entry(hisptr);
+	    --hisnum[histype];
+	    if (--hisidx[HIST_SEARCH] < 0)
+		hisidx[HIST_SEARCH] = hislen - 1;
+	}
+	last_maptick = -1;
+    }
+    if (!in_history(histype, new_entry, TRUE, sep, FALSE))
+    {
+	if (++hisidx[histype] == hislen)
+	    hisidx[histype] = 0;
+	hisptr = &history[histype][hisidx[histype]];
+	vim_free(hisptr->hisstr);
+
+	// Store the separator after the NUL of the string.
+	len = (int)STRLEN(new_entry);
+	hisptr->hisstr = vim_strnsave(new_entry, len + 2);
+	if (hisptr->hisstr != NULL)
+	    hisptr->hisstr[len + 1] = sep;
+
+	hisptr->hisnum = ++hisnum[histype];
+	hisptr->viminfo = FALSE;
+	hisptr->time_set = vim_time();
+	if (histype == HIST_SEARCH && in_map)
+	    last_maptick = maptick;
+    }
+}
+
+#if defined(FEAT_EVAL) || defined(PROTO)
+
+/*
+ * Get identifier of newest history entry.
+ * "histype" may be one of the HIST_ values.
+ */
+    static int
+get_history_idx(int histype)
+{
+    if (hislen == 0 || histype < 0 || histype >= HIST_COUNT
+		    || hisidx[histype] < 0)
+	return -1;
+
+    return history[histype][hisidx[histype]].hisnum;
+}
+
+/*
+ * Calculate history index from a number:
+ *   num > 0: seen as identifying number of a history entry
+ *   num < 0: relative position in history wrt newest entry
+ * "histype" may be one of the HIST_ values.
+ */
+    static int
+calc_hist_idx(int histype, int num)
+{
+    int		i;
+    histentry_T	*hist;
+    int		wrapped = FALSE;
+
+    if (hislen == 0 || histype < 0 || histype >= HIST_COUNT
+		    || (i = hisidx[histype]) < 0 || num == 0)
+	return -1;
+
+    hist = history[histype];
+    if (num > 0)
+    {
+	while (hist[i].hisnum > num)
+	    if (--i < 0)
+	    {
+		if (wrapped)
+		    break;
+		i += hislen;
+		wrapped = TRUE;
+	    }
+	if (hist[i].hisnum == num && hist[i].hisstr != NULL)
+	    return i;
+    }
+    else if (-num <= hislen)
+    {
+	i += num + 1;
+	if (i < 0)
+	    i += hislen;
+	if (hist[i].hisstr != NULL)
+	    return i;
+    }
+    return -1;
+}
+
+/*
+ * Get a history entry by its index.
+ * "histype" may be one of the HIST_ values.
+ */
+    static char_u *
+get_history_entry(int histype, int idx)
+{
+    idx = calc_hist_idx(histype, idx);
+    if (idx >= 0)
+	return history[histype][idx].hisstr;
+    else
+	return (char_u *)"";
+}
+
+/*
+ * Clear all entries of a history.
+ * "histype" may be one of the HIST_ values.
+ */
+    static int
+clr_history(int histype)
+{
+    int		i;
+    histentry_T	*hisptr;
+
+    if (hislen != 0 && histype >= 0 && histype < HIST_COUNT)
+    {
+	hisptr = history[histype];
+	for (i = hislen; i--;)
+	{
+	    vim_free(hisptr->hisstr);
+	    clear_hist_entry(hisptr);
+	    hisptr++;
+	}
+	hisidx[histype] = -1;	// mark history as cleared
+	hisnum[histype] = 0;	// reset identifier counter
+	return OK;
+    }
+    return FAIL;
+}
+
+/*
+ * Remove all entries matching {str} from a history.
+ * "histype" may be one of the HIST_ values.
+ */
+    static int
+del_history_entry(int histype, char_u *str)
+{
+    regmatch_T	regmatch;
+    histentry_T	*hisptr;
+    int		idx;
+    int		i;
+    int		last;
+    int		found = FALSE;
+
+    regmatch.regprog = NULL;
+    regmatch.rm_ic = FALSE;	// always match case
+    if (hislen != 0
+	    && histype >= 0
+	    && histype < HIST_COUNT
+	    && *str != NUL
+	    && (idx = hisidx[histype]) >= 0
+	    && (regmatch.regprog = vim_regcomp(str, RE_MAGIC + RE_STRING))
+								      != NULL)
+    {
+	i = last = idx;
+	do
+	{
+	    hisptr = &history[histype][i];
+	    if (hisptr->hisstr == NULL)
+		break;
+	    if (vim_regexec(&regmatch, hisptr->hisstr, (colnr_T)0))
+	    {
+		found = TRUE;
+		vim_free(hisptr->hisstr);
+		clear_hist_entry(hisptr);
+	    }
+	    else
+	    {
+		if (i != last)
+		{
+		    history[histype][last] = *hisptr;
+		    clear_hist_entry(hisptr);
+		}
+		if (--last < 0)
+		    last += hislen;
+	    }
+	    if (--i < 0)
+		i += hislen;
+	} while (i != idx);
+	if (history[histype][idx].hisstr == NULL)
+	    hisidx[histype] = -1;
+    }
+    vim_regfree(regmatch.regprog);
+    return found;
+}
+
+/*
+ * Remove an indexed entry from a history.
+ * "histype" may be one of the HIST_ values.
+ */
+    static int
+del_history_idx(int histype, int idx)
+{
+    int	    i, j;
+
+    i = calc_hist_idx(histype, idx);
+    if (i < 0)
+	return FALSE;
+    idx = hisidx[histype];
+    vim_free(history[histype][i].hisstr);
+
+    // When deleting the last added search string in a mapping, reset
+    // last_maptick, so that the last added search string isn't deleted again.
+    if (histype == HIST_SEARCH && maptick == last_maptick && i == idx)
+	last_maptick = -1;
+
+    while (i != idx)
+    {
+	j = (i + 1) % hislen;
+	history[histype][i] = history[histype][j];
+	i = j;
+    }
+    clear_hist_entry(&history[histype][i]);
+    if (--i < 0)
+	i += hislen;
+    hisidx[histype] = i;
+    return TRUE;
+}
+
+/*
+ * "histadd()" function
+ */
+    void
+f_histadd(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    int		histype;
+    char_u	*str;
+    char_u	buf[NUMBUFLEN];
+
+    rettv->vval.v_number = FALSE;
+    if (check_secure())
+	return;
+    str = tv_get_string_chk(&argvars[0]);	// NULL on type error
+    histype = str != NULL ? get_histtype(str) : -1;
+    if (histype >= 0)
+    {
+	str = tv_get_string_buf(&argvars[1], buf);
+	if (*str != NUL)
+	{
+	    init_history();
+	    add_to_history(histype, str, FALSE, NUL);
+	    rettv->vval.v_number = TRUE;
+	    return;
+	}
+    }
+}
+
+/*
+ * "histdel()" function
+ */
+    void
+f_histdel(typval_T *argvars UNUSED, typval_T *rettv UNUSED)
+{
+    int		n;
+    char_u	buf[NUMBUFLEN];
+    char_u	*str;
+
+    str = tv_get_string_chk(&argvars[0]);	// NULL on type error
+    if (str == NULL)
+	n = 0;
+    else if (argvars[1].v_type == VAR_UNKNOWN)
+	// only one argument: clear entire history
+	n = clr_history(get_histtype(str));
+    else if (argvars[1].v_type == VAR_NUMBER)
+	// index given: remove that entry
+	n = del_history_idx(get_histtype(str),
+					  (int)tv_get_number(&argvars[1]));
+    else
+	// string given: remove all matching entries
+	n = del_history_entry(get_histtype(str),
+				      tv_get_string_buf(&argvars[1], buf));
+    rettv->vval.v_number = n;
+}
+
+/*
+ * "histget()" function
+ */
+    void
+f_histget(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    int		type;
+    int		idx;
+    char_u	*str;
+
+    str = tv_get_string_chk(&argvars[0]);	// NULL on type error
+    if (str == NULL)
+	rettv->vval.v_string = NULL;
+    else
+    {
+	type = get_histtype(str);
+	if (argvars[1].v_type == VAR_UNKNOWN)
+	    idx = get_history_idx(type);
+	else
+	    idx = (int)tv_get_number_chk(&argvars[1], NULL);
+						    // -1 on type error
+	rettv->vval.v_string = vim_strsave(get_history_entry(type, idx));
+    }
+    rettv->v_type = VAR_STRING;
+}
+
+/*
+ * "histnr()" function
+ */
+    void
+f_histnr(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    int		i;
+
+    char_u	*histname = tv_get_string_chk(&argvars[0]);
+
+    i = histname == NULL ? HIST_CMD - 1 : get_histtype(histname);
+    if (i >= HIST_CMD && i < HIST_COUNT)
+	i = get_history_idx(i);
+    else
+	i = -1;
+    rettv->vval.v_number = i;
+}
+#endif // FEAT_EVAL
+
+#if defined(FEAT_CRYPT) || defined(PROTO)
+/*
+ * Very specific function to remove the value in ":set key=val" from the
+ * history.
+ */
+    void
+remove_key_from_history(void)
+{
+    char_u	*p;
+    int		i;
+
+    i = hisidx[HIST_CMD];
+    if (i < 0)
+	return;
+    p = history[HIST_CMD][i].hisstr;
+    if (p != NULL)
+	for ( ; *p; ++p)
+	    if (STRNCMP(p, "key", 3) == 0 && !isalpha(p[3]))
+	    {
+		p = vim_strchr(p + 3, '=');
+		if (p == NULL)
+		    break;
+		++p;
+		for (i = 0; p[i] && !VIM_ISWHITE(p[i]); ++i)
+		    if (p[i] == '\\' && p[i + 1])
+			++i;
+		STRMOVE(p, p + i);
+		--p;
+	    }
+}
+#endif
+
+/*
+ * :history command - print a history
+ */
+    void
+ex_history(exarg_T *eap)
+{
+    histentry_T	*hist;
+    int		histype1 = HIST_CMD;
+    int		histype2 = HIST_CMD;
+    int		hisidx1 = 1;
+    int		hisidx2 = -1;
+    int		idx;
+    int		i, j, k;
+    char_u	*end;
+    char_u	*arg = eap->arg;
+
+    if (hislen == 0)
+    {
+	msg(_("'history' option is zero"));
+	return;
+    }
+
+    if (!(VIM_ISDIGIT(*arg) || *arg == '-' || *arg == ','))
+    {
+	end = arg;
+	while (ASCII_ISALPHA(*end)
+		|| vim_strchr((char_u *)":=@>/?", *end) != NULL)
+	    end++;
+	i = *end;
+	*end = NUL;
+	histype1 = get_histtype(arg);
+	if (histype1 == -1)
+	{
+	    if (STRNICMP(arg, "all", STRLEN(arg)) == 0)
+	    {
+		histype1 = 0;
+		histype2 = HIST_COUNT-1;
+	    }
+	    else
+	    {
+		*end = i;
+		emsg(_(e_trailing));
+		return;
+	    }
+	}
+	else
+	    histype2 = histype1;
+	*end = i;
+    }
+    else
+	end = arg;
+    if (!get_list_range(&end, &hisidx1, &hisidx2) || *end != NUL)
+    {
+	emsg(_(e_trailing));
+	return;
+    }
+
+    for (; !got_int && histype1 <= histype2; ++histype1)
+    {
+	STRCPY(IObuff, "\n      #  ");
+	STRCAT(STRCAT(IObuff, history_names[histype1]), " history");
+	msg_puts_title((char *)IObuff);
+	idx = hisidx[histype1];
+	hist = history[histype1];
+	j = hisidx1;
+	k = hisidx2;
+	if (j < 0)
+	    j = (-j > hislen) ? 0 : hist[(hislen+j+idx+1) % hislen].hisnum;
+	if (k < 0)
+	    k = (-k > hislen) ? 0 : hist[(hislen+k+idx+1) % hislen].hisnum;
+	if (idx >= 0 && j <= k)
+	    for (i = idx + 1; !got_int; ++i)
+	    {
+		if (i == hislen)
+		    i = 0;
+		if (hist[i].hisstr != NULL
+			&& hist[i].hisnum >= j && hist[i].hisnum <= k)
+		{
+		    msg_putchar('\n');
+		    sprintf((char *)IObuff, "%c%6d  ", i == idx ? '>' : ' ',
+							      hist[i].hisnum);
+		    if (vim_strsize(hist[i].hisstr) > (int)Columns - 10)
+			trunc_string(hist[i].hisstr, IObuff + STRLEN(IObuff),
+			     (int)Columns - 10, IOSIZE - (int)STRLEN(IObuff));
+		    else
+			STRCAT(IObuff, hist[i].hisstr);
+		    msg_outtrans(IObuff);
+		    out_flush();
+		}
+		if (i == idx)
+		    break;
+	    }
+    }
+}