[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/libbb/lineedit.c b/ap/app/busybox/src/libbb/lineedit.c
new file mode 100755
index 0000000..61fe006
--- /dev/null
+++ b/ap/app/busybox/src/libbb/lineedit.c
@@ -0,0 +1,2787 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Command line editing.
+ *
+ * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
+ * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
+ *
+ * Used ideas:
+ *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
+ *      Dave Cinege      <dcinege@psychosis.com>
+ *      Jakub Jelinek (c) 1995
+ *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
+ *
+ * This code is 'as is' with no warranty.
+ */
+
+/*
+ * Usage and known bugs:
+ * Terminal key codes are not extensive, more needs to be added.
+ * This version was created on Debian GNU/Linux 2.x.
+ * Delete, Backspace, Home, End, and the arrow keys were tested
+ * to work in an Xterm and console. Ctrl-A also works as Home.
+ * Ctrl-E also works as End.
+ *
+ * The following readline-like commands are not implemented:
+ * ESC-b -- Move back one word
+ * ESC-f -- Move forward one word
+ * ESC-d -- Delete forward one word
+ * CTL-t -- Transpose two characters
+ *
+ * lineedit does not know that the terminal escape sequences do not
+ * take up space on the screen. The redisplay code assumes, unless
+ * told otherwise, that each character in the prompt is a printable
+ * character that takes up one character position on the screen.
+ * You need to tell lineedit that some sequences of characters
+ * in the prompt take up no screen space. Compatibly with readline,
+ * use the \[ escape to begin a sequence of non-printing characters,
+ * and the \] escape to signal the end of such a sequence. Example:
+ *
+ * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
+ */
+#include "libbb.h"
+#include "unicode.h"
+#ifndef _POSIX_VDISABLE
+# define _POSIX_VDISABLE '\0'
+#endif
+
+
+#ifdef TEST
+# define ENABLE_FEATURE_EDITING 0
+# define ENABLE_FEATURE_TAB_COMPLETION 0
+# define ENABLE_FEATURE_USERNAME_COMPLETION 0
+#endif
+
+
+/* Entire file (except TESTing part) sits inside this #if */
+#if ENABLE_FEATURE_EDITING
+
+
+#define ENABLE_USERNAME_OR_HOMEDIR \
+	(ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
+#define IF_USERNAME_OR_HOMEDIR(...)
+#if ENABLE_USERNAME_OR_HOMEDIR
+# undef IF_USERNAME_OR_HOMEDIR
+# define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
+#endif
+
+
+#undef CHAR_T
+#if ENABLE_UNICODE_SUPPORT
+# define BB_NUL ((wchar_t)0)
+# define CHAR_T wchar_t
+static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
+# if ENABLE_FEATURE_EDITING_VI
+static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
+# endif
+static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
+# undef isspace
+# undef isalnum
+# undef ispunct
+# undef isprint
+# define isspace isspace_must_not_be_used
+# define isalnum isalnum_must_not_be_used
+# define ispunct ispunct_must_not_be_used
+# define isprint isprint_must_not_be_used
+#else
+# define BB_NUL '\0'
+# define CHAR_T char
+# define BB_isspace(c) isspace(c)
+# define BB_isalnum(c) isalnum(c)
+# define BB_ispunct(c) ispunct(c)
+#endif
+#if ENABLE_UNICODE_PRESERVE_BROKEN
+# define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
+# define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
+#else
+# define unicode_is_raw_byte(wc)     0
+#endif
+
+
+#define ESC "\033"
+
+#define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
+//#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
+
+
+enum {
+	MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
+	              ? CONFIG_FEATURE_EDITING_MAX_LEN
+	              : 0x7ff0
+};
+
+#if ENABLE_USERNAME_OR_HOMEDIR
+static const char null_str[] ALIGN1 = "";
+#endif
+
+/* We try to minimize both static and stack usage. */
+struct lineedit_statics {
+	line_input_t *state;
+
+	volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
+	sighandler_t previous_SIGWINCH_handler;
+
+	unsigned cmdedit_x;        /* real x (col) terminal position */
+	unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
+	unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
+
+	unsigned cursor;
+	int command_len; /* must be signed */
+	/* signed maxsize: we want x in "if (x > S.maxsize)"
+	 * to _not_ be promoted to unsigned */
+	int maxsize;
+	CHAR_T *command_ps;
+
+	const char *cmdedit_prompt;
+#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+	int num_ok_lines; /* = 1; */
+#endif
+
+#if ENABLE_USERNAME_OR_HOMEDIR
+	char *user_buf;
+	char *home_pwd_buf; /* = (char*)null_str; */
+#endif
+
+#if ENABLE_FEATURE_TAB_COMPLETION
+	char **matches;
+	unsigned num_matches;
+#endif
+
+#if ENABLE_FEATURE_EDITING_VI
+# define DELBUFSIZ 128
+	CHAR_T *delptr;
+	smallint newdelflag;     /* whether delbuf should be reused yet */
+	CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
+#endif
+#if ENABLE_FEATURE_EDITING_ASK_TERMINAL
+	smallint sent_ESC_br6n;
+#endif
+};
+
+/* See lineedit_ptr_hack.c */
+extern struct lineedit_statics *const lineedit_ptr_to_statics;
+
+#define S (*lineedit_ptr_to_statics)
+#define state            (S.state           )
+#define cmdedit_termw    (S.cmdedit_termw   )
+#define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
+#define cmdedit_x        (S.cmdedit_x       )
+#define cmdedit_y        (S.cmdedit_y       )
+#define cmdedit_prmt_len (S.cmdedit_prmt_len)
+#define cursor           (S.cursor          )
+#define command_len      (S.command_len     )
+#define command_ps       (S.command_ps      )
+#define cmdedit_prompt   (S.cmdedit_prompt  )
+#define num_ok_lines     (S.num_ok_lines    )
+#define user_buf         (S.user_buf        )
+#define home_pwd_buf     (S.home_pwd_buf    )
+#define matches          (S.matches         )
+#define num_matches      (S.num_matches     )
+#define delptr           (S.delptr          )
+#define newdelflag       (S.newdelflag      )
+#define delbuf           (S.delbuf          )
+
+#define INIT_S() do { \
+	(*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
+	barrier(); \
+	cmdedit_termw = 80; \
+	IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
+	IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
+} while (0)
+
+static void deinit_S(void)
+{
+#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+	/* This one is allocated only if FANCY_PROMPT is on
+	 * (otherwise it points to verbatim prompt (NOT malloced)) */
+	free((char*)cmdedit_prompt);
+#endif
+#if ENABLE_USERNAME_OR_HOMEDIR
+	free(user_buf);
+	if (home_pwd_buf != null_str)
+		free(home_pwd_buf);
+#endif
+	free(lineedit_ptr_to_statics);
+}
+#define DEINIT_S() deinit_S()
+
+
+#if ENABLE_UNICODE_SUPPORT
+static size_t load_string(const char *src)
+{
+	if (unicode_status == UNICODE_ON) {
+		ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
+		if (len < 0)
+			len = 0;
+		command_ps[len] = BB_NUL;
+		return len;
+	} else {
+		unsigned i = 0;
+		while (src[i] && i < S.maxsize - 1) {
+			command_ps[i] = src[i];
+			i++;
+		}
+		command_ps[i] = BB_NUL;
+		return i;
+	}
+}
+static unsigned save_string(char *dst, unsigned maxsize)
+{
+	if (unicode_status == UNICODE_ON) {
+# if !ENABLE_UNICODE_PRESERVE_BROKEN
+		ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
+		if (len < 0)
+			len = 0;
+		dst[len] = '\0';
+		return len;
+# else
+		unsigned dstpos = 0;
+		unsigned srcpos = 0;
+
+		maxsize--;
+		while (dstpos < maxsize) {
+			wchar_t wc;
+			int n = srcpos;
+
+			/* Convert up to 1st invalid byte (or up to end) */
+			while ((wc = command_ps[srcpos]) != BB_NUL
+			    && !unicode_is_raw_byte(wc)
+			) {
+				srcpos++;
+			}
+			command_ps[srcpos] = BB_NUL;
+			n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
+			if (n < 0) /* should not happen */
+				break;
+			dstpos += n;
+			if (wc == BB_NUL) /* usually is */
+				break;
+
+			/* We do have invalid byte here! */
+			command_ps[srcpos] = wc; /* restore it */
+			srcpos++;
+			if (dstpos == maxsize)
+				break;
+			dst[dstpos++] = (char) wc;
+		}
+		dst[dstpos] = '\0';
+		return dstpos;
+# endif
+	} else {
+		unsigned i = 0;
+		while ((dst[i] = command_ps[i]) != 0)
+			i++;
+		return i;
+	}
+}
+/* I thought just fputwc(c, stdout) would work. But no... */
+static void BB_PUTCHAR(wchar_t c)
+{
+	if (unicode_status == UNICODE_ON) {
+		char buf[MB_CUR_MAX + 1];
+		mbstate_t mbst = { 0 };
+		ssize_t len = wcrtomb(buf, c, &mbst);
+		if (len > 0) {
+			buf[len] = '\0';
+			fputs(buf, stdout);
+		}
+	} else {
+		/* In this case, c is always one byte */
+		putchar(c);
+	}
+}
+# if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
+static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
+# else
+static wchar_t adjust_width_and_validate_wc(wchar_t wc)
+#  define adjust_width_and_validate_wc(width_adj, wc) \
+	((*(width_adj))++, adjust_width_and_validate_wc(wc))
+# endif
+{
+	int w = 1;
+
+	if (unicode_status == UNICODE_ON) {
+		if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
+			/* note: also true for unicode_is_raw_byte(wc) */
+			goto subst;
+		}
+		w = wcwidth(wc);
+		if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
+		 || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
+		 || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
+		) {
+ subst:
+			w = 1;
+			wc = CONFIG_SUBST_WCHAR;
+		}
+	}
+
+# if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
+	*width_adj += w;
+#endif
+	return wc;
+}
+#else /* !UNICODE */
+static size_t load_string(const char *src)
+{
+	safe_strncpy(command_ps, src, S.maxsize);
+	return strlen(command_ps);
+}
+# if ENABLE_FEATURE_TAB_COMPLETION
+static void save_string(char *dst, unsigned maxsize)
+{
+	safe_strncpy(dst, command_ps, maxsize);
+}
+# endif
+# define BB_PUTCHAR(c) bb_putchar(c)
+/* Should never be called: */
+int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
+#endif
+
+
+/* Put 'command_ps[cursor]', cursor++.
+ * Advance cursor on screen. If we reached right margin, scroll text up
+ * and remove terminal margin effect by printing 'next_char' */
+#define HACK_FOR_WRONG_WIDTH 1
+static void put_cur_glyph_and_inc_cursor(void)
+{
+	CHAR_T c = command_ps[cursor];
+	unsigned width = 0;
+	int ofs_to_right;
+
+	if (c == BB_NUL) {
+		/* erase character after end of input string */
+		c = ' ';
+	} else {
+		/* advance cursor only if we aren't at the end yet */
+		cursor++;
+		if (unicode_status == UNICODE_ON) {
+			IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
+			c = adjust_width_and_validate_wc(&cmdedit_x, c);
+			IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
+		} else {
+			cmdedit_x++;
+		}
+	}
+
+	ofs_to_right = cmdedit_x - cmdedit_termw;
+	if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
+		/* c fits on this line */
+		BB_PUTCHAR(c);
+	}
+
+	if (ofs_to_right >= 0) {
+		/* we go to the next line */
+#if HACK_FOR_WRONG_WIDTH
+		/* This works better if our idea of term width is wrong
+		 * and it is actually wider (often happens on serial lines).
+		 * Printing CR,LF *forces* cursor to next line.
+		 * OTOH if terminal width is correct AND terminal does NOT
+		 * have automargin (IOW: it is moving cursor to next line
+		 * by itself (which is wrong for VT-10x terminals)),
+		 * this will break things: there will be one extra empty line */
+		puts("\r"); /* + implicit '\n' */
+#else
+		/* VT-10x terminals don't wrap cursor to next line when last char
+		 * on the line is printed - cursor stays "over" this char.
+		 * Need to print _next_ char too (first one to appear on next line)
+		 * to make cursor move down to next line.
+		 */
+		/* Works ok only if cmdedit_termw is correct. */
+		c = command_ps[cursor];
+		if (c == BB_NUL)
+			c = ' ';
+		BB_PUTCHAR(c);
+		bb_putchar('\b');
+#endif
+		cmdedit_y++;
+		if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
+			width = 0;
+		} else { /* ofs_to_right > 0 */
+			/* wide char c didn't fit on prev line */
+			BB_PUTCHAR(c);
+		}
+		cmdedit_x = width;
+	}
+}
+
+/* Move to end of line (by printing all chars till the end) */
+static void put_till_end_and_adv_cursor(void)
+{
+	while (cursor < command_len)
+		put_cur_glyph_and_inc_cursor();
+}
+
+/* Go to the next line */
+static void goto_new_line(void)
+{
+	put_till_end_and_adv_cursor();
+	if (cmdedit_x != 0)
+		bb_putchar('\n');
+}
+
+static void beep(void)
+{
+	bb_putchar('\007');
+}
+
+static void put_prompt(void)
+{
+	unsigned w;
+
+	fputs(cmdedit_prompt, stdout);
+	fflush_all();
+	cursor = 0;
+	w = cmdedit_termw; /* read volatile var once */
+	cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
+	cmdedit_x = cmdedit_prmt_len % w;
+}
+
+/* Move back one character */
+/* (optimized for slow terminals) */
+static void input_backward(unsigned num)
+{
+	if (num > cursor)
+		num = cursor;
+	if (num == 0)
+		return;
+	cursor -= num;
+
+	if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
+	 && unicode_status == UNICODE_ON
+	) {
+		/* correct NUM to be equal to _screen_ width */
+		int n = num;
+		num = 0;
+		while (--n >= 0)
+			adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
+		if (num == 0)
+			return;
+	}
+
+	if (cmdedit_x >= num) {
+		cmdedit_x -= num;
+		if (num <= 4) {
+			/* This is longer by 5 bytes on x86.
+			 * Also gets miscompiled for ARM users
+			 * (busybox.net/bugs/view.php?id=2274).
+			 * printf(("\b\b\b\b" + 4) - num);
+			 * return;
+			 */
+			do {
+				bb_putchar('\b');
+			} while (--num);
+			return;
+		}
+		printf(ESC"[%uD", num);
+		return;
+	}
+
+	/* Need to go one or more lines up */
+	if (ENABLE_UNICODE_WIDE_WCHARS) {
+		/* With wide chars, it is hard to "backtrack"
+		 * and reliably figure out where to put cursor.
+		 * Example (<> is a wide char; # is an ordinary char, _ cursor):
+		 * |prompt: <><> |
+		 * |<><><><><><> |
+		 * |_            |
+		 * and user presses left arrow. num = 1, cmdedit_x = 0,
+		 * We need to go up one line, and then - how do we know that
+		 * we need to go *10* positions to the right? Because
+		 * |prompt: <>#<>|
+		 * |<><><>#<><><>|
+		 * |_            |
+		 * in this situation we need to go *11* positions to the right.
+		 *
+		 * A simpler thing to do is to redraw everything from the start
+		 * up to new cursor position (which is already known):
+		 */
+		unsigned sv_cursor;
+		/* go to 1st column; go up to first line */
+		printf("\r" ESC"[%uA", cmdedit_y);
+		cmdedit_y = 0;
+		sv_cursor = cursor;
+		put_prompt(); /* sets cursor to 0 */
+		while (cursor < sv_cursor)
+			put_cur_glyph_and_inc_cursor();
+	} else {
+		int lines_up;
+		unsigned width;
+		/* num = chars to go back from the beginning of current line: */
+		num -= cmdedit_x;
+		width = cmdedit_termw; /* read volatile var once */
+		/* num=1...w: one line up, w+1...2w: two, etc: */
+		lines_up = 1 + (num - 1) / width;
+		cmdedit_x = (width * cmdedit_y - num) % width;
+		cmdedit_y -= lines_up;
+		/* go to 1st column; go up */
+		printf("\r" ESC"[%uA", lines_up);
+		/* go to correct column.
+		 * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
+		 * need to *make sure* we skip it if cmdedit_x == 0 */
+		if (cmdedit_x)
+			printf(ESC"[%uC", cmdedit_x);
+	}
+}
+
+/* draw prompt, editor line, and clear tail */
+static void redraw(int y, int back_cursor)
+{
+	if (y > 0) /* up y lines */
+		printf(ESC"[%uA", y);
+	bb_putchar('\r');
+	put_prompt();
+	put_till_end_and_adv_cursor();
+	printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
+	input_backward(back_cursor);
+}
+
+/* Delete the char in front of the cursor, optionally saving it
+ * for later putback */
+#if !ENABLE_FEATURE_EDITING_VI
+static void input_delete(void)
+#define input_delete(save) input_delete()
+#else
+static void input_delete(int save)
+#endif
+{
+	int j = cursor;
+
+	if (j == (int)command_len)
+		return;
+
+#if ENABLE_FEATURE_EDITING_VI
+	if (save) {
+		if (newdelflag) {
+			delptr = delbuf;
+			newdelflag = 0;
+		}
+		if ((delptr - delbuf) < DELBUFSIZ)
+			*delptr++ = command_ps[j];
+	}
+#endif
+
+	memmove(command_ps + j, command_ps + j + 1,
+			/* (command_len + 1 [because of NUL]) - (j + 1)
+			 * simplified into (command_len - j) */
+			(command_len - j) * sizeof(command_ps[0]));
+	command_len--;
+	put_till_end_and_adv_cursor();
+	/* Last char is still visible, erase it (and more) */
+	printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
+	input_backward(cursor - j);     /* back to old pos cursor */
+}
+
+#if ENABLE_FEATURE_EDITING_VI
+static void put(void)
+{
+	int ocursor;
+	int j = delptr - delbuf;
+
+	if (j == 0)
+		return;
+	ocursor = cursor;
+	/* open hole and then fill it */
+	memmove(command_ps + cursor + j, command_ps + cursor,
+			(command_len - cursor + 1) * sizeof(command_ps[0]));
+	memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
+	command_len += j;
+	put_till_end_and_adv_cursor();
+	input_backward(cursor - ocursor - j + 1); /* at end of new text */
+}
+#endif
+
+/* Delete the char in back of the cursor */
+static void input_backspace(void)
+{
+	if (cursor > 0) {
+		input_backward(1);
+		input_delete(0);
+	}
+}
+
+/* Move forward one character */
+static void input_forward(void)
+{
+	if (cursor < command_len)
+		put_cur_glyph_and_inc_cursor();
+}
+
+#if ENABLE_FEATURE_TAB_COMPLETION
+
+//FIXME:
+//needs to be more clever: currently it thinks that "foo\ b<TAB>
+//matches the file named "foo bar", which is untrue.
+//Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
+//not "foo bar <cursor>...
+
+static void free_tab_completion_data(void)
+{
+	if (matches) {
+		while (num_matches)
+			free(matches[--num_matches]);
+		free(matches);
+		matches = NULL;
+	}
+}
+
+static void add_match(char *matched)
+{
+	/*CVE-2017-16544 https://git.busybox.net/busybox/commit/?id=c3797d40a1c57352192c6106cc0f435e7d9c11e8*/
+	unsigned char *p = (unsigned char*)matched;
+	while (*p) {
+		/* ESC attack fix: drop any string with control chars */
+		if (*p < ' '
+		 || (!ENABLE_UNICODE_SUPPORT && *p >= 0x7f)
+		 || (ENABLE_UNICODE_SUPPORT && *p == 0x7f)
+		) {
+			free(matched);
+			return;
+		}
+		p++;
+	}
+	matches = xrealloc_vector(matches, 4, num_matches);
+	matches[num_matches] = matched;
+	num_matches++;
+}
+
+# if ENABLE_FEATURE_USERNAME_COMPLETION
+/* Replace "~user/..." with "/homedir/...".
+ * The parameter is malloced, free it or return it
+ * unchanged if no user is matched.
+ */
+static char *username_path_completion(char *ud)
+{
+	struct passwd *entry;
+	char *tilde_name = ud;
+	char *home = NULL;
+
+	ud++; /* skip ~ */
+	if (*ud == '/') {       /* "~/..." */
+		home = home_pwd_buf;
+	} else {
+		/* "~user/..." */
+		ud = strchr(ud, '/');
+		*ud = '\0';           /* "~user" */
+		entry = getpwnam(tilde_name + 1);
+		*ud = '/';            /* restore "~user/..." */
+		if (entry)
+			home = entry->pw_dir;
+	}
+	if (home) {
+		ud = concat_path_file(home, ud);
+		free(tilde_name);
+		tilde_name = ud;
+	}
+	return tilde_name;
+}
+
+/* ~use<tab> - find all users with this prefix.
+ * Return the length of the prefix used for matching.
+ */
+static NOINLINE unsigned complete_username(const char *ud)
+{
+	/* Using _r function to avoid pulling in static buffers */
+	char line_buff[256];
+	struct passwd pwd;
+	struct passwd *result;
+	unsigned userlen;
+
+	ud++; /* skip ~ */
+	userlen = strlen(ud);
+
+	setpwent();
+	while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
+		/* Null usernames should result in all users as possible completions. */
+		if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
+			add_match(xasprintf("~%s/", pwd.pw_name));
+		}
+	}
+	endpwent();
+
+	return 1 + userlen;
+}
+# endif  /* FEATURE_USERNAME_COMPLETION */
+
+enum {
+	FIND_EXE_ONLY = 0,
+	FIND_DIR_ONLY = 1,
+	FIND_FILE_ONLY = 2,
+};
+
+static int path_parse(char ***p)
+{
+	int npth;
+	const char *pth;
+	char *tmp;
+	char **res;
+
+	if (state->flags & WITH_PATH_LOOKUP)
+		pth = state->path_lookup;
+	else
+		pth = getenv("PATH");
+
+	/* PATH="" or PATH=":"? */
+	if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
+		return 1;
+
+	tmp = (char*)pth;
+	npth = 1; /* path component count */
+	while (1) {
+		tmp = strchr(tmp, ':');
+		if (!tmp)
+			break;
+		tmp++;
+		if (*tmp == '\0')
+			break;  /* :<empty> */
+		npth++;
+	}
+
+	*p = res = xmalloc(npth * sizeof(res[0]));
+	res[0] = tmp = xstrdup(pth);
+	npth = 1;
+	while (1) {
+		tmp = strchr(tmp, ':');
+		if (!tmp)
+			break;
+		*tmp++ = '\0'; /* ':' -> '\0' */
+		if (*tmp == '\0')
+			break; /* :<empty> */
+		res[npth++] = tmp;
+	}
+	return npth;
+}
+
+/* Complete command, directory or file name.
+ * Return the length of the prefix used for matching.
+ */
+static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
+{
+	char *path1[1];
+	char **paths = path1;
+	int npaths;
+	int i;
+	unsigned pf_len;
+	const char *pfind;
+	char *dirbuf = NULL;
+
+	npaths = 1;
+	path1[0] = (char*)".";
+
+	pfind = strrchr(command, '/');
+	if (!pfind) {
+		if (type == FIND_EXE_ONLY)
+			npaths = path_parse(&paths);
+		pfind = command;
+	} else {
+		/* point to 'l' in "..../last_component" */
+		pfind++;
+		/* dirbuf = ".../.../.../" */
+		dirbuf = xstrndup(command, pfind - command);
+# if ENABLE_FEATURE_USERNAME_COMPLETION
+		if (dirbuf[0] == '~')   /* ~/... or ~user/... */
+			dirbuf = username_path_completion(dirbuf);
+# endif
+		path1[0] = dirbuf;
+	}
+	pf_len = strlen(pfind);
+
+	for (i = 0; i < npaths; i++) {
+		DIR *dir;
+		struct dirent *next;
+		struct stat st;
+		char *found;
+
+		dir = opendir(paths[i]);
+		if (!dir)
+			continue; /* don't print an error */
+
+		while ((next = readdir(dir)) != NULL) {
+			unsigned len;
+			const char *name_found = next->d_name;
+
+			/* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
+			if (!pfind[0] && DOT_OR_DOTDOT(name_found))
+				continue;
+			/* match? */
+			if (strncmp(name_found, pfind, pf_len) != 0)
+				continue; /* no */
+
+			found = concat_path_file(paths[i], name_found);
+			/* NB: stat() first so that we see is it a directory;
+			 * but if that fails, use lstat() so that
+			 * we still match dangling links */
+			if (stat(found, &st) && lstat(found, &st))
+				goto cont; /* hmm, remove in progress? */
+
+			/* Save only name */
+			len = strlen(name_found);
+			found = xrealloc(found, len + 2); /* +2: for slash and NUL */
+			strcpy(found, name_found);
+
+			if (S_ISDIR(st.st_mode)) {
+				/* name is a directory, add slash */
+				found[len] = '/';
+				found[len + 1] = '\0';
+			} else {
+				/* skip files if looking for dirs only (example: cd) */
+				if (type == FIND_DIR_ONLY)
+					goto cont;
+			}
+			/* add it to the list */
+			add_match(found);
+			continue;
+ cont:
+			free(found);
+		}
+		closedir(dir);
+	} /* for every path */
+
+	if (paths != path1) {
+		free(paths[0]); /* allocated memory is only in first member */
+		free(paths);
+	}
+	free(dirbuf);
+
+	return pf_len;
+}
+
+/* build_match_prefix:
+ * On entry, match_buf contains everything up to cursor at the moment <tab>
+ * was pressed. This function looks at it, figures out what part of it
+ * constitutes the command/file/directory prefix to use for completion,
+ * and rewrites match_buf to contain only that part.
+ */
+#define dbg_bmp 0
+/* Helpers: */
+/* QUOT is used on elements of int_buf[], which are bytes,
+ * not Unicode chars. Therefore it works correctly even in Unicode mode.
+ */
+#define QUOT (UCHAR_MAX+1)
+static void remove_chunk(int16_t *int_buf, int beg, int end)
+{
+	/* beg must be <= end */
+	if (beg == end)
+		return;
+
+	while ((int_buf[beg] = int_buf[end]) != 0)
+		beg++, end++;
+
+	if (dbg_bmp) {
+		int i;
+		for (i = 0; int_buf[i]; i++)
+			bb_putchar((unsigned char)int_buf[i]);
+		bb_putchar('\n');
+	}
+}
+/* Caller ensures that match_buf points to a malloced buffer
+ * big enough to hold strlen(match_buf)*2 + 2
+ */
+static NOINLINE int build_match_prefix(char *match_buf)
+{
+	int i, j;
+	int command_mode;
+	int16_t *int_buf = (int16_t*)match_buf;
+
+	if (dbg_bmp) printf("\n%s\n", match_buf);
+
+	/* Copy in reverse order, since they overlap */
+	i = strlen(match_buf);
+	do {
+		int_buf[i] = (unsigned char)match_buf[i];
+		i--;
+	} while (i >= 0);
+
+	/* Mark every \c as "quoted c" */
+	for (i = 0; int_buf[i]; i++) {
+		if (int_buf[i] == '\\') {
+			remove_chunk(int_buf, i, i + 1);
+			int_buf[i] |= QUOT;
+		}
+	}
+	/* Quote-mark "chars" and 'chars', drop delimiters */
+	{
+		int in_quote = 0;
+		i = 0;
+		while (int_buf[i]) {
+			int cur = int_buf[i];
+			if (!cur)
+				break;
+			if (cur == '\'' || cur == '"') {
+				if (!in_quote || (cur == in_quote)) {
+					in_quote ^= cur;
+					remove_chunk(int_buf, i, i + 1);
+					continue;
+				}
+			}
+			if (in_quote)
+				int_buf[i] = cur | QUOT;
+			i++;
+		}
+	}
+
+	/* Remove everything up to command delimiters:
+	 * ';' ';;' '&' '|' '&&' '||',
+	 * but careful with '>&' '<&' '>|'
+	 */
+	for (i = 0; int_buf[i]; i++) {
+		int cur = int_buf[i];
+		if (cur == ';' || cur == '&' || cur == '|') {
+			int prev = i ? int_buf[i - 1] : 0;
+			if (cur == '&' && (prev == '>' || prev == '<')) {
+				continue;
+			} else if (cur == '|' && prev == '>') {
+				continue;
+			}
+			remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
+			i = -1;  /* back to square 1 */
+		}
+	}
+	/* Remove all `cmd` */
+	for (i = 0; int_buf[i]; i++) {
+		if (int_buf[i] == '`') {
+			for (j = i + 1; int_buf[j]; j++) {
+				if (int_buf[j] == '`') {
+					/* `cmd` should count as a word:
+					 * `cmd` c<tab> should search for files c*,
+					 * not commands c*. Therefore we don't drop
+					 * `cmd` entirely, we replace it with single `.
+					 */
+					remove_chunk(int_buf, i, j);
+					goto next;
+				}
+			}
+			/* No closing ` - command mode, remove all up to ` */
+			remove_chunk(int_buf, 0, i + 1);
+			break;
+ next: ;
+		}
+	}
+
+	/* Remove "cmd (" and "cmd {"
+	 * Example: "if { c<tab>"
+	 * In this example, c should be matched as command pfx.
+	 */
+	for (i = 0; int_buf[i]; i++) {
+		if (int_buf[i] == '(' || int_buf[i] == '{') {
+			remove_chunk(int_buf, 0, i + 1);
+			i = -1;  /* back to square 1 */
+		}
+	}
+
+	/* Remove leading unquoted spaces */
+	for (i = 0; int_buf[i]; i++)
+		if (int_buf[i] != ' ')
+			break;
+	remove_chunk(int_buf, 0, i);
+
+	/* Determine completion mode */
+	command_mode = FIND_EXE_ONLY;
+	for (i = 0; int_buf[i]; i++) {
+		if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
+			if (int_buf[i] == ' '
+			 && command_mode == FIND_EXE_ONLY
+			 && (char)int_buf[0] == 'c'
+			 && (char)int_buf[1] == 'd'
+			 && i == 2 /* -> int_buf[2] == ' ' */
+			) {
+				command_mode = FIND_DIR_ONLY;
+			} else {
+				command_mode = FIND_FILE_ONLY;
+				break;
+			}
+		}
+	}
+	if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
+
+	/* Remove everything except last word */
+	for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
+		continue;
+	for (--i; i >= 0; i--) {
+		int cur = int_buf[i];
+		if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
+			remove_chunk(int_buf, 0, i + 1);
+			break;
+		}
+	}
+
+	/* Convert back to string of _chars_ */
+	i = 0;
+	while ((match_buf[i] = int_buf[i]) != '\0')
+		i++;
+
+	if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
+
+	return command_mode;
+}
+
+/*
+ * Display by column (original idea from ls applet,
+ * very optimized by me [Vladimir] :)
+ */
+static void showfiles(void)
+{
+	int ncols, row;
+	int column_width = 0;
+	int nfiles = num_matches;
+	int nrows = nfiles;
+	int l;
+
+	/* find the longest file name - use that as the column width */
+	for (row = 0; row < nrows; row++) {
+		l = unicode_strwidth(matches[row]);
+		if (column_width < l)
+			column_width = l;
+	}
+	column_width += 2;              /* min space for columns */
+	ncols = cmdedit_termw / column_width;
+
+	if (ncols > 1) {
+		nrows /= ncols;
+		if (nfiles % ncols)
+			nrows++;        /* round up fractionals */
+	} else {
+		ncols = 1;
+	}
+	for (row = 0; row < nrows; row++) {
+		int n = row;
+		int nc;
+
+		for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
+			printf("%s%-*s", matches[n],
+				(int)(column_width - unicode_strwidth(matches[n])), ""
+			);
+		}
+		if (ENABLE_UNICODE_SUPPORT)
+			puts(printable_string(NULL, matches[n]));
+		else
+			puts(matches[n]);
+	}
+}
+
+static const char *is_special_char(char c)
+{
+	return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
+}
+
+static char *quote_special_chars(char *found)
+{
+	int l = 0;
+	char *s = xzalloc((strlen(found) + 1) * 2);
+
+	while (*found) {
+		if (is_special_char(*found))
+			s[l++] = '\\';
+		s[l++] = *found++;
+	}
+	/* s[l] = '\0'; - already is */
+	return s;
+}
+
+/* Do TAB completion */
+static NOINLINE void input_tab(smallint *lastWasTab)
+{
+	char *chosen_match;
+	char *match_buf;
+	size_t len_found;
+	/* Length of string used for matching */
+	unsigned match_pfx_len = match_pfx_len;
+	int find_type;
+# if ENABLE_UNICODE_SUPPORT
+	/* cursor pos in command converted to multibyte form */
+	int cursor_mb;
+# endif
+	if (!(state->flags & TAB_COMPLETION))
+		return;
+
+	if (*lastWasTab) {
+		/* The last char was a TAB too.
+		 * Print a list of all the available choices.
+		 */
+		if (num_matches > 0) {
+			/* cursor will be changed by goto_new_line() */
+			int sav_cursor = cursor;
+			goto_new_line();
+			showfiles();
+			redraw(0, command_len - sav_cursor);
+		}
+		return;
+	}
+
+	*lastWasTab = 1;
+	chosen_match = NULL;
+
+	/* Make a local copy of the string up to the position of the cursor.
+	 * build_match_prefix will expand it into int16_t's, need to allocate
+	 * twice as much as the string_len+1.
+	 * (we then also (ab)use this extra space later - see (**))
+	 */
+	match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
+# if !ENABLE_UNICODE_SUPPORT
+	save_string(match_buf, cursor + 1); /* +1 for NUL */
+# else
+	{
+		CHAR_T wc = command_ps[cursor];
+		command_ps[cursor] = BB_NUL;
+		save_string(match_buf, MAX_LINELEN);
+		command_ps[cursor] = wc;
+		cursor_mb = strlen(match_buf);
+	}
+# endif
+	find_type = build_match_prefix(match_buf);
+
+	/* Free up any memory already allocated */
+	free_tab_completion_data();
+
+# if ENABLE_FEATURE_USERNAME_COMPLETION
+	/* If the word starts with ~ and there is no slash in the word,
+	 * then try completing this word as a username. */
+	if (state->flags & USERNAME_COMPLETION)
+		if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
+			match_pfx_len = complete_username(match_buf);
+# endif
+	/* If complete_username() did not match,
+	 * try to match a command in $PATH, or a directory, or a file */
+	if (!matches)
+		match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
+
+	/* Account for backslashes which will be inserted
+	 * by quote_special_chars() later */
+	{
+		const char *e = match_buf + strlen(match_buf);
+		const char *s = e - match_pfx_len;
+		while (s < e)
+			if (is_special_char(*s++))
+				match_pfx_len++;
+	}
+
+	/* Remove duplicates */
+	if (matches) {
+		unsigned i, n = 0;
+		qsort_string_vector(matches, num_matches);
+		for (i = 0; i < num_matches - 1; ++i) {
+			//if (matches[i] && matches[i+1]) { /* paranoia */
+				if (strcmp(matches[i], matches[i+1]) == 0) {
+					free(matches[i]);
+					//matches[i] = NULL; /* paranoia */
+				} else {
+					matches[n++] = matches[i];
+				}
+			//}
+		}
+		matches[n++] = matches[i];
+		num_matches = n;
+	}
+
+	/* Did we find exactly one match? */
+	if (num_matches != 1) { /* no */
+		char *cp;
+		beep();
+		if (!matches)
+			goto ret; /* no matches at all */
+		/* Find common prefix */
+		chosen_match = xstrdup(matches[0]);
+		for (cp = chosen_match; *cp; cp++) {
+			unsigned n;
+			for (n = 1; n < num_matches; n++) {
+				if (matches[n][cp - chosen_match] != *cp) {
+					goto stop;
+				}
+			}
+		}
+ stop:
+		if (cp == chosen_match) { /* have unique prefix? */
+			goto ret; /* no */
+		}
+		*cp = '\0';
+		cp = quote_special_chars(chosen_match);
+		free(chosen_match);
+		chosen_match = cp;
+		len_found = strlen(chosen_match);
+	} else {                        /* exactly one match */
+		/* Next <tab> is not a double-tab */
+		*lastWasTab = 0;
+
+		chosen_match = quote_special_chars(matches[0]);
+		len_found = strlen(chosen_match);
+		if (chosen_match[len_found-1] != '/') {
+			chosen_match[len_found] = ' ';
+			chosen_match[++len_found] = '\0';
+		}
+	}
+
+# if !ENABLE_UNICODE_SUPPORT
+	/* Have space to place the match? */
+	/* The result consists of three parts with these lengths: */
+	/* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
+	/* it simplifies into: */
+	if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
+		int pos;
+		/* save tail */
+		strcpy(match_buf, &command_ps[cursor]);
+		/* add match and tail */
+		sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
+		command_len = strlen(command_ps);
+		/* new pos */
+		pos = cursor + len_found - match_pfx_len;
+		/* write out the matched command */
+		redraw(cmdedit_y, command_len - pos);
+	}
+# else
+	{
+		/* Use 2nd half of match_buf as scratch space - see (**) */
+		char *command = match_buf + MAX_LINELEN;
+		int len = save_string(command, MAX_LINELEN);
+		/* Have space to place the match? */
+		/* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
+		if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
+			int pos;
+			/* save tail */
+			strcpy(match_buf, &command[cursor_mb]);
+			/* where do we want to have cursor after all? */
+			strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
+			len = load_string(command);
+			/* add match and tail */
+			sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
+			command_len = load_string(command);
+			/* write out the matched command */
+			/* paranoia: load_string can return 0 on conv error,
+			 * prevent passing pos = (0 - 12) to redraw */
+			pos = command_len - len;
+			redraw(cmdedit_y, pos >= 0 ? pos : 0);
+		}
+	}
+# endif
+ ret:
+	free(chosen_match);
+	free(match_buf);
+}
+
+#endif  /* FEATURE_TAB_COMPLETION */
+
+
+line_input_t* FAST_FUNC new_line_input_t(int flags)
+{
+	line_input_t *n = xzalloc(sizeof(*n));
+	n->flags = flags;
+	n->max_history = MAX_HISTORY;
+	return n;
+}
+
+
+#if MAX_HISTORY > 0
+
+unsigned size_from_HISTFILESIZE(const char *hp)
+{
+	int size = MAX_HISTORY;
+	if (hp) {
+		size = atoi(hp);
+		if (size <= 0)
+			return 1;
+		if (size > MAX_HISTORY)
+			return MAX_HISTORY;
+	}
+	return size;
+}
+
+static void save_command_ps_at_cur_history(void)
+{
+	if (command_ps[0] != BB_NUL) {
+		int cur = state->cur_history;
+		free(state->history[cur]);
+
+# if ENABLE_UNICODE_SUPPORT
+		{
+			char tbuf[MAX_LINELEN];
+			save_string(tbuf, sizeof(tbuf));
+			state->history[cur] = xstrdup(tbuf);
+		}
+# else
+		state->history[cur] = xstrdup(command_ps);
+# endif
+	}
+}
+
+/* state->flags is already checked to be nonzero */
+static int get_previous_history(void)
+{
+	if ((state->flags & DO_HISTORY) && state->cur_history) {
+		save_command_ps_at_cur_history();
+		state->cur_history--;
+		return 1;
+	}
+	beep();
+	return 0;
+}
+
+static int get_next_history(void)
+{
+	if (state->flags & DO_HISTORY) {
+		if (state->cur_history < state->cnt_history) {
+			save_command_ps_at_cur_history(); /* save the current history line */
+			return ++state->cur_history;
+		}
+	}
+	beep();
+	return 0;
+}
+
+# if ENABLE_FEATURE_EDITING_SAVEHISTORY
+/* We try to ensure that concurrent additions to the history
+ * do not overwrite each other.
+ * Otherwise shell users get unhappy.
+ *
+ * History file is trimmed lazily, when it grows several times longer
+ * than configured MAX_HISTORY lines.
+ */
+
+static void free_line_input_t(line_input_t *n)
+{
+	int i = n->cnt_history;
+	while (i > 0)
+		free(n->history[--i]);
+	free(n);
+}
+
+/* state->flags is already checked to be nonzero */
+static void load_history(line_input_t *st_parm)
+{
+	char *temp_h[MAX_HISTORY];
+	char *line;
+	FILE *fp;
+	unsigned idx, i, line_len;
+
+	/* NB: do not trash old history if file can't be opened */
+
+	fp = fopen_for_read(st_parm->hist_file);
+	if (fp) {
+		/* clean up old history */
+		for (idx = st_parm->cnt_history; idx > 0;) {
+			idx--;
+			free(st_parm->history[idx]);
+			st_parm->history[idx] = NULL;
+		}
+
+		/* fill temp_h[], retaining only last MAX_HISTORY lines */
+		memset(temp_h, 0, sizeof(temp_h));
+		idx = 0;
+		st_parm->cnt_history_in_file = 0;
+		while ((line = xmalloc_fgetline(fp)) != NULL) {
+			if (line[0] == '\0') {
+				free(line);
+				continue;
+			}
+			free(temp_h[idx]);
+			temp_h[idx] = line;
+			st_parm->cnt_history_in_file++;
+			idx++;
+			if (idx == st_parm->max_history)
+				idx = 0;
+		}
+		fclose(fp);
+
+		/* find first non-NULL temp_h[], if any */
+		if (st_parm->cnt_history_in_file) {
+			while (temp_h[idx] == NULL) {
+				idx++;
+				if (idx == st_parm->max_history)
+					idx = 0;
+			}
+		}
+
+		/* copy temp_h[] to st_parm->history[] */
+		for (i = 0; i < st_parm->max_history;) {
+			line = temp_h[idx];
+			if (!line)
+				break;
+			idx++;
+			if (idx == st_parm->max_history)
+				idx = 0;
+			line_len = strlen(line);
+			if (line_len >= MAX_LINELEN)
+				line[MAX_LINELEN-1] = '\0';
+			st_parm->history[i++] = line;
+		}
+		st_parm->cnt_history = i;
+		if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
+			st_parm->cnt_history_in_file = i;
+	}
+}
+
+#  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
+void save_history(line_input_t *st)
+{
+	FILE *fp;
+
+	if (!st->hist_file)
+		return;
+	if (st->cnt_history <= st->cnt_history_in_file)
+		return;
+
+	fp = fopen(st->hist_file, "a");
+	if (fp) {
+		int i, fd;
+		char *new_name;
+		line_input_t *st_temp;
+
+		for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
+			fprintf(fp, "%s\n", st->history[i]);
+		fclose(fp);
+
+		/* we may have concurrently written entries from others.
+		 * load them */
+		st_temp = new_line_input_t(st->flags);
+		st_temp->hist_file = st->hist_file;
+		st_temp->max_history = st->max_history;
+		load_history(st_temp);
+
+		/* write out temp file and replace hist_file atomically */
+		new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
+		fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+		if (fd >= 0) {
+			fp = xfdopen_for_write(fd);
+			for (i = 0; i < st_temp->cnt_history; i++)
+				fprintf(fp, "%s\n", st_temp->history[i]);
+			fclose(fp);
+			if (rename(new_name, st->hist_file) == 0)
+				st->cnt_history_in_file = st_temp->cnt_history;
+		}
+		free(new_name);
+		free_line_input_t(st_temp);
+	}
+}
+#  else
+static void save_history(char *str)
+{
+	int fd;
+	int len, len2;
+
+	if (!state->hist_file)
+		return;
+
+	fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
+	if (fd < 0)
+		return;
+	xlseek(fd, 0, SEEK_END); /* paranoia */
+	len = strlen(str);
+	str[len] = '\n'; /* we (try to) do atomic write */
+	len2 = full_write(fd, str, len + 1);
+	str[len] = '\0';
+	close(fd);
+	if (len2 != len + 1)
+		return; /* "wtf?" */
+
+	/* did we write so much that history file needs trimming? */
+	state->cnt_history_in_file++;
+	if (state->cnt_history_in_file > state->max_history * 4) {
+		char *new_name;
+		line_input_t *st_temp;
+
+		/* we may have concurrently written entries from others.
+		 * load them */
+		st_temp = new_line_input_t(state->flags);
+		st_temp->hist_file = state->hist_file;
+		st_temp->max_history = state->max_history;
+		load_history(st_temp);
+
+		/* write out temp file and replace hist_file atomically */
+		new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
+		fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+		if (fd >= 0) {
+			FILE *fp;
+			int i;
+
+			fp = xfdopen_for_write(fd);
+			for (i = 0; i < st_temp->cnt_history; i++)
+				fprintf(fp, "%s\n", st_temp->history[i]);
+			fclose(fp);
+			if (rename(new_name, state->hist_file) == 0)
+				state->cnt_history_in_file = st_temp->cnt_history;
+		}
+		free(new_name);
+		free_line_input_t(st_temp);
+	}
+}
+#  endif
+# else
+#  define load_history(a) ((void)0)
+#  define save_history(a) ((void)0)
+# endif /* FEATURE_COMMAND_SAVEHISTORY */
+
+static void remember_in_history(char *str)
+{
+	int i;
+
+	if (!(state->flags & DO_HISTORY))
+		return;
+	if (str[0] == '\0')
+		return;
+	i = state->cnt_history;
+	/* Don't save dupes */
+	if (i && strcmp(state->history[i-1], str) == 0)
+		return;
+
+	free(state->history[state->max_history]); /* redundant, paranoia */
+	state->history[state->max_history] = NULL; /* redundant, paranoia */
+
+	/* If history[] is full, remove the oldest command */
+	/* we need to keep history[state->max_history] empty, hence >=, not > */
+	if (i >= state->max_history) {
+		free(state->history[0]);
+		for (i = 0; i < state->max_history-1; i++)
+			state->history[i] = state->history[i+1];
+		/* i == state->max_history-1 */
+# if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
+		if (state->cnt_history_in_file)
+			state->cnt_history_in_file--;
+# endif
+	}
+	/* i <= state->max_history-1 */
+	state->history[i++] = xstrdup(str);
+	/* i <= state->max_history */
+	state->cur_history = i;
+	state->cnt_history = i;
+# if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
+	save_history(str);
+# endif
+	IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines++;)
+}
+
+#else /* MAX_HISTORY == 0 */
+# define remember_in_history(a) ((void)0)
+#endif /* MAX_HISTORY */
+
+
+#if ENABLE_FEATURE_EDITING_VI
+/*
+ * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
+ */
+static void
+vi_Word_motion(int eat)
+{
+	CHAR_T *command = command_ps;
+
+	while (cursor < command_len && !BB_isspace(command[cursor]))
+		input_forward();
+	if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
+		input_forward();
+}
+
+static void
+vi_word_motion(int eat)
+{
+	CHAR_T *command = command_ps;
+
+	if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
+		while (cursor < command_len
+		 && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
+		) {
+			input_forward();
+		}
+	} else if (BB_ispunct(command[cursor])) {
+		while (cursor < command_len && BB_ispunct(command[cursor+1]))
+			input_forward();
+	}
+
+	if (cursor < command_len)
+		input_forward();
+
+	if (eat) {
+		while (cursor < command_len && BB_isspace(command[cursor]))
+			input_forward();
+	}
+}
+
+static void
+vi_End_motion(void)
+{
+	CHAR_T *command = command_ps;
+
+	input_forward();
+	while (cursor < command_len && BB_isspace(command[cursor]))
+		input_forward();
+	while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
+		input_forward();
+}
+
+static void
+vi_end_motion(void)
+{
+	CHAR_T *command = command_ps;
+
+	if (cursor >= command_len-1)
+		return;
+	input_forward();
+	while (cursor < command_len-1 && BB_isspace(command[cursor]))
+		input_forward();
+	if (cursor >= command_len-1)
+		return;
+	if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
+		while (cursor < command_len-1
+		 && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
+		) {
+			input_forward();
+		}
+	} else if (BB_ispunct(command[cursor])) {
+		while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
+			input_forward();
+	}
+}
+
+static void
+vi_Back_motion(void)
+{
+	CHAR_T *command = command_ps;
+
+	while (cursor > 0 && BB_isspace(command[cursor-1]))
+		input_backward(1);
+	while (cursor > 0 && !BB_isspace(command[cursor-1]))
+		input_backward(1);
+}
+
+static void
+vi_back_motion(void)
+{
+	CHAR_T *command = command_ps;
+
+	if (cursor <= 0)
+		return;
+	input_backward(1);
+	while (cursor > 0 && BB_isspace(command[cursor]))
+		input_backward(1);
+	if (cursor <= 0)
+		return;
+	if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
+		while (cursor > 0
+		 && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
+		) {
+			input_backward(1);
+		}
+	} else if (BB_ispunct(command[cursor])) {
+		while (cursor > 0 && BB_ispunct(command[cursor-1]))
+			input_backward(1);
+	}
+}
+#endif
+
+/* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
+static void ctrl_left(void)
+{
+	CHAR_T *command = command_ps;
+
+	while (1) {
+		CHAR_T c;
+
+		input_backward(1);
+		if (cursor == 0)
+			break;
+		c = command[cursor];
+		if (c != ' ' && !BB_ispunct(c)) {
+			/* we reached a "word" delimited by spaces/punct.
+			 * go to its beginning */
+			while (1) {
+				c = command[cursor - 1];
+				if (c == ' ' || BB_ispunct(c))
+					break;
+				input_backward(1);
+				if (cursor == 0)
+					break;
+			}
+			break;
+		}
+	}
+}
+static void ctrl_right(void)
+{
+	CHAR_T *command = command_ps;
+
+	while (1) {
+		CHAR_T c;
+
+		c = command[cursor];
+		if (c == BB_NUL)
+			break;
+		if (c != ' ' && !BB_ispunct(c)) {
+			/* we reached a "word" delimited by spaces/punct.
+			 * go to its end + 1 */
+			while (1) {
+				input_forward();
+				c = command[cursor];
+				if (c == BB_NUL || c == ' ' || BB_ispunct(c))
+					break;
+			}
+			break;
+		}
+		input_forward();
+	}
+}
+
+
+/*
+ * read_line_input and its helpers
+ */
+
+#if ENABLE_FEATURE_EDITING_ASK_TERMINAL
+static void ask_terminal(void)
+{
+	/* Ask terminal where is the cursor now.
+	 * lineedit_read_key handles response and corrects
+	 * our idea of current cursor position.
+	 * Testcase: run "echo -n long_line_long_line_long_line",
+	 * then type in a long, wrapping command and try to
+	 * delete it using backspace key.
+	 * Note: we print it _after_ prompt, because
+	 * prompt may contain CR. Example: PS1='\[\r\n\]\w '
+	 */
+	/* Problem: if there is buffered input on stdin,
+	 * the response will be delivered later,
+	 * possibly to an unsuspecting application.
+	 * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
+	 * Result:
+	 * ~/srcdevel/bbox/fix/busybox.t4 #
+	 * ~/srcdevel/bbox/fix/busybox.t4 #
+	 * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
+	 * ~/srcdevel/bbox/fix/busybox.t4 #
+	 *
+	 * Checking for input with poll only makes the race narrower,
+	 * I still can trigger it. Strace:
+	 *
+	 * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
+	 * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
+	 * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
+	 * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
+	 * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
+	 */
+	struct pollfd pfd;
+
+	pfd.fd = STDIN_FILENO;
+	pfd.events = POLLIN;
+	if (safe_poll(&pfd, 1, 0) == 0) {
+		S.sent_ESC_br6n = 1;
+		fputs(ESC"[6n", stdout);
+		fflush_all(); /* make terminal see it ASAP! */
+	}
+}
+#else
+#define ask_terminal() ((void)0)
+#endif
+
+#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
+static void parse_and_put_prompt(const char *prmt_ptr)
+{
+	cmdedit_prompt = prmt_ptr;
+	cmdedit_prmt_len = strlen(prmt_ptr);
+	put_prompt();
+}
+#else
+static void parse_and_put_prompt(const char *prmt_ptr)
+{
+	int prmt_len = 0;
+	size_t cur_prmt_len = 0;
+	char flg_not_length = '[';
+	char *prmt_mem_ptr = xzalloc(1);
+	char *cwd_buf = xrealloc_getcwd_or_warn(NULL);
+	char cbuf[2];
+	char c;
+	char *pbuf;
+
+	cmdedit_prmt_len = 0;
+
+	if (!cwd_buf) {
+		cwd_buf = (char *)bb_msg_unknown;
+	}
+
+	cbuf[1] = '\0'; /* never changes */
+
+	while (*prmt_ptr) {
+		char *free_me = NULL;
+
+		pbuf = cbuf;
+		c = *prmt_ptr++;
+		if (c == '\\') {
+			const char *cp = prmt_ptr;
+			int l;
+
+			c = bb_process_escape_sequence(&prmt_ptr);
+			if (prmt_ptr == cp) {
+				if (*cp == '\0')
+					break;
+				c = *prmt_ptr++;
+
+				switch (c) {
+# if ENABLE_USERNAME_OR_HOMEDIR
+				case 'u':
+					pbuf = user_buf ? user_buf : (char*)"";
+					break;
+# endif
+				case 'h':
+					pbuf = free_me = safe_gethostname();
+					*strchrnul(pbuf, '.') = '\0';
+					break;
+				case '$':
+					c = (geteuid() == 0 ? '#' : '$');
+					break;
+# if ENABLE_USERNAME_OR_HOMEDIR
+				case 'w':
+					/* /home/user[/something] -> ~[/something] */
+					pbuf = cwd_buf;
+					l = strlen(home_pwd_buf);
+					if (l != 0
+					 && strncmp(home_pwd_buf, cwd_buf, l) == 0
+					 && (cwd_buf[l]=='/' || cwd_buf[l]=='\0')
+					 && strlen(cwd_buf + l) < PATH_MAX
+					) {
+						pbuf = free_me = xasprintf("~%s", cwd_buf + l);
+					}
+					break;
+# endif
+				case 'W':
+					pbuf = cwd_buf;
+					cp = strrchr(pbuf, '/');
+					if (cp != NULL && cp != pbuf)
+						pbuf += (cp-pbuf) + 1;
+					break;
+				case '!':
+					pbuf = free_me = xasprintf("%d", num_ok_lines);
+					break;
+				case 'e': case 'E':     /* \e \E = \033 */
+					c = '\033';
+					break;
+				case 'x': case 'X': {
+					char buf2[4];
+					for (l = 0; l < 3;) {
+						unsigned h;
+						buf2[l++] = *prmt_ptr;
+						buf2[l] = '\0';
+						h = strtoul(buf2, &pbuf, 16);
+						if (h > UCHAR_MAX || (pbuf - buf2) < l) {
+							buf2[--l] = '\0';
+							break;
+						}
+						prmt_ptr++;
+					}
+					c = (char)strtoul(buf2, NULL, 16);
+					if (c == 0)
+						c = '?';
+					pbuf = cbuf;
+					break;
+				}
+				case '[': case ']':
+					if (c == flg_not_length) {
+						flg_not_length = (flg_not_length == '[' ? ']' : '[');
+						continue;
+					}
+					break;
+				} /* switch */
+			} /* if */
+		} /* if */
+		cbuf[0] = c;
+		cur_prmt_len = strlen(pbuf);
+		prmt_len += cur_prmt_len;
+		if (flg_not_length != ']')
+			cmdedit_prmt_len += cur_prmt_len;
+		prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_len+1), pbuf);
+		free(free_me);
+	} /* while */
+
+	if (cwd_buf != (char *)bb_msg_unknown)
+		free(cwd_buf);
+	cmdedit_prompt = prmt_mem_ptr;
+	put_prompt();
+}
+#endif
+
+static void cmdedit_setwidth(unsigned w, int redraw_flg)
+{
+	cmdedit_termw = w;
+	if (redraw_flg) {
+		/* new y for current cursor */
+		int new_y = (cursor + cmdedit_prmt_len) / w;
+		/* redraw */
+		redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
+		fflush_all();
+	}
+}
+
+static void win_changed(int nsig)
+{
+	int sv_errno = errno;
+	unsigned width;
+
+	get_terminal_width_height(0, &width, NULL);
+//FIXME: cmdedit_setwidth() -> redraw() -> printf() -> KABOOM! (we are in signal handler!)
+	cmdedit_setwidth(width, /*redraw_flg:*/ nsig);
+
+	errno = sv_errno;
+}
+
+static int lineedit_read_key(char *read_key_buffer, int timeout)
+{
+	int64_t ic;
+#if ENABLE_UNICODE_SUPPORT
+	char unicode_buf[MB_CUR_MAX + 1];
+	int unicode_idx = 0;
+#endif
+
+	while (1) {
+		/* Wait for input. TIMEOUT = -1 makes read_key wait even
+		 * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
+		 * insist on full MB_CUR_MAX buffer to declare input like
+		 * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
+		 *
+		 * Note: read_key sets errno to 0 on success.
+		 */
+		ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
+		if (errno) {
+#if ENABLE_UNICODE_SUPPORT
+			if (errno == EAGAIN && unicode_idx != 0)
+				goto pushback;
+#endif
+			break;
+		}
+
+#if ENABLE_FEATURE_EDITING_ASK_TERMINAL
+		if ((int32_t)ic == KEYCODE_CURSOR_POS
+		 && S.sent_ESC_br6n
+		) {
+			S.sent_ESC_br6n = 0;
+			if (cursor == 0) { /* otherwise it may be bogus */
+				int col = ((ic >> 32) & 0x7fff) - 1;
+				if (col > cmdedit_prmt_len) {
+					cmdedit_x += (col - cmdedit_prmt_len);
+					while (cmdedit_x >= cmdedit_termw) {
+						cmdedit_x -= cmdedit_termw;
+						cmdedit_y++;
+					}
+				}
+			}
+			continue;
+		}
+#endif
+
+#if ENABLE_UNICODE_SUPPORT
+		if (unicode_status == UNICODE_ON) {
+			wchar_t wc;
+
+			if ((int32_t)ic < 0) /* KEYCODE_xxx */
+				break;
+			// TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
+
+			unicode_buf[unicode_idx++] = ic;
+			unicode_buf[unicode_idx] = '\0';
+			if (mbstowcs(&wc, unicode_buf, 1) != 1) {
+				/* Not (yet?) a valid unicode char */
+				if (unicode_idx < MB_CUR_MAX) {
+					timeout = 50;
+					continue;
+				}
+ pushback:
+				/* Invalid sequence. Save all "bad bytes" except first */
+				read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
+# if !ENABLE_UNICODE_PRESERVE_BROKEN
+				ic = CONFIG_SUBST_WCHAR;
+# else
+				ic = unicode_mark_raw_byte(unicode_buf[0]);
+# endif
+			} else {
+				/* Valid unicode char, return its code */
+				ic = wc;
+			}
+		}
+#endif
+		break;
+	}
+
+	return ic;
+}
+
+#if ENABLE_UNICODE_BIDI_SUPPORT
+static int isrtl_str(void)
+{
+	int idx = cursor;
+
+	while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
+		idx++;
+	return unicode_bidi_isrtl(command_ps[idx]);
+}
+#else
+# define isrtl_str() 0
+#endif
+
+/* leave out the "vi-mode"-only case labels if vi editing isn't
+ * configured. */
+#define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
+
+/* convert uppercase ascii to equivalent control char, for readability */
+#undef CTRL
+#define CTRL(a) ((a) & ~0x40)
+
+enum {
+	VI_CMDMODE_BIT = 0x40000000,
+	/* 0x80000000 bit flags KEYCODE_xxx */
+};
+
+#if ENABLE_FEATURE_REVERSE_SEARCH
+/* Mimic readline Ctrl-R reverse history search.
+ * When invoked, it shows the following prompt:
+ * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
+ * and typing results in search being performed:
+ * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
+ * Search is performed by looking at progressively older lines in history.
+ * Ctrl-R again searches for the next match in history.
+ * Backspace deletes last matched char.
+ * Control keys exit search and return to normal editing (at current history line).
+ */
+static int32_t reverse_i_search(void)
+{
+	char match_buf[128]; /* for user input */
+	char read_key_buffer[KEYCODE_BUFFER_SIZE];
+	const char *matched_history_line;
+	const char *saved_prompt;
+	int32_t ic;
+
+	matched_history_line = NULL;
+	read_key_buffer[0] = 0;
+	match_buf[0] = '\0';
+
+	/* Save and replace the prompt */
+	saved_prompt = cmdedit_prompt;
+	goto set_prompt;
+
+	while (1) {
+		int h;
+		unsigned match_buf_len = strlen(match_buf);
+
+		fflush_all();
+//FIXME: correct timeout?
+		ic = lineedit_read_key(read_key_buffer, -1);
+
+		switch (ic) {
+		case CTRL('R'): /* searching for the next match */
+			break;
+
+		case '\b':
+		case '\x7f':
+			/* Backspace */
+			if (unicode_status == UNICODE_ON) {
+				while (match_buf_len != 0) {
+					uint8_t c = match_buf[--match_buf_len];
+					if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
+						break; /* yes */
+				}
+			} else {
+				if (match_buf_len != 0)
+					match_buf_len--;
+			}
+			match_buf[match_buf_len] = '\0';
+			break;
+
+		default:
+			if (ic < ' '
+			 || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
+			 || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
+			) {
+				goto ret;
+			}
+
+			/* Append this char */
+#if ENABLE_UNICODE_SUPPORT
+			if (unicode_status == UNICODE_ON) {
+				mbstate_t mbstate = { 0 };
+				char buf[MB_CUR_MAX + 1];
+				int len = wcrtomb(buf, ic, &mbstate);
+				if (len > 0) {
+					buf[len] = '\0';
+					if (match_buf_len + len < sizeof(match_buf))
+						strcpy(match_buf + match_buf_len, buf);
+				}
+			} else
+#endif
+			if (match_buf_len < sizeof(match_buf) - 1) {
+				match_buf[match_buf_len] = ic;
+				match_buf[match_buf_len + 1] = '\0';
+			}
+			break;
+		} /* switch (ic) */
+
+		/* Search in history for match_buf */
+		h = state->cur_history;
+		if (ic == CTRL('R'))
+			h--;
+		while (h >= 0) {
+			if (state->history[h]) {
+				char *match = strstr(state->history[h], match_buf);
+				if (match) {
+					state->cur_history = h;
+					matched_history_line = state->history[h];
+					command_len = load_string(matched_history_line);
+					cursor = match - matched_history_line;
+//FIXME: cursor position for Unicode case
+
+					free((char*)cmdedit_prompt);
+ set_prompt:
+					cmdedit_prompt = xasprintf("(reverse-i-search)'%s': ", match_buf);
+					cmdedit_prmt_len = strlen(cmdedit_prompt);
+					goto do_redraw;
+				}
+			}
+			h--;
+		}
+
+		/* Not found */
+		match_buf[match_buf_len] = '\0';
+		beep();
+		continue;
+
+ do_redraw:
+		redraw(cmdedit_y, command_len - cursor);
+	} /* while (1) */
+
+ ret:
+	if (matched_history_line)
+		command_len = load_string(matched_history_line);
+
+	free((char*)cmdedit_prompt);
+	cmdedit_prompt = saved_prompt;
+	cmdedit_prmt_len = strlen(cmdedit_prompt);
+	redraw(cmdedit_y, command_len - cursor);
+
+	return ic;
+}
+#endif
+
+/* maxsize must be >= 2.
+ * Returns:
+ * -1 on read errors or EOF, or on bare Ctrl-D,
+ * 0  on ctrl-C (the line entered is still returned in 'command'),
+ * >0 length of input string, including terminating '\n'
+ */
+int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize, int timeout)
+{
+	int len;
+#if ENABLE_FEATURE_TAB_COMPLETION
+	smallint lastWasTab = 0;
+#endif
+	smallint break_out = 0;
+#if ENABLE_FEATURE_EDITING_VI
+	smallint vi_cmdmode = 0;
+#endif
+	struct termios initial_settings;
+	struct termios new_settings;
+	char read_key_buffer[KEYCODE_BUFFER_SIZE];
+
+	INIT_S();
+
+	if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
+	 || !(initial_settings.c_lflag & ECHO)
+	) {
+		/* Happens when e.g. stty -echo was run before */
+		parse_and_put_prompt(prompt);
+		/* fflush_all(); - done by parse_and_put_prompt */
+		if (fgets(command, maxsize, stdin) == NULL)
+			len = -1; /* EOF or error */
+		else
+			len = strlen(command);
+		DEINIT_S();
+		return len;
+	}
+
+	init_unicode();
+
+// FIXME: audit & improve this
+	if (maxsize > MAX_LINELEN)
+		maxsize = MAX_LINELEN;
+	S.maxsize = maxsize;
+
+	/* With zero flags, no other fields are ever used */
+	state = st ? st : (line_input_t*) &const_int_0;
+#if MAX_HISTORY > 0
+# if ENABLE_FEATURE_EDITING_SAVEHISTORY
+	if (state->hist_file)
+		if (state->cnt_history == 0)
+			load_history(state);
+# endif
+	if (state->flags & DO_HISTORY)
+		state->cur_history = state->cnt_history;
+#endif
+
+	/* prepare before init handlers */
+	cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
+	command_len = 0;
+#if ENABLE_UNICODE_SUPPORT
+	command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
+#else
+	command_ps = command;
+	command[0] = '\0';
+#endif
+#define command command_must_not_be_used
+
+	new_settings = initial_settings;
+	/* ~ICANON: unbuffered input (most c_cc[] are disabled, VMIN/VTIME are enabled) */
+	/* ~ECHO, ~ECHONL: turn off echoing, including newline echoing */
+	/* ~ISIG: turn off INTR (ctrl-C), QUIT, SUSP */
+	new_settings.c_lflag &= ~(ICANON | ECHO | ECHONL | ISIG);
+	/* reads would block only if < 1 char is available */
+	new_settings.c_cc[VMIN] = 1;
+	/* no timeout (reads block forever) */
+	new_settings.c_cc[VTIME] = 0;
+	/* Should be not needed if ISIG is off: */
+	/* Turn off CTRL-C */
+	/* new_settings.c_cc[VINTR] = _POSIX_VDISABLE; */
+	tcsetattr_stdin_TCSANOW(&new_settings);
+
+#if ENABLE_USERNAME_OR_HOMEDIR
+	{
+		struct passwd *entry;
+
+		entry = getpwuid(geteuid());
+		if (entry) {
+			user_buf = xstrdup(entry->pw_name);
+			home_pwd_buf = xstrdup(entry->pw_dir);
+		}
+	}
+#endif
+
+#if 0
+	for (i = 0; i <= state->max_history; i++)
+		bb_error_msg("history[%d]:'%s'", i, state->history[i]);
+	bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
+#endif
+
+	/* Print out the command prompt, optionally ask where cursor is */
+	parse_and_put_prompt(prompt);
+	ask_terminal();
+
+	/* Install window resize handler (NB: after *all* init is complete) */
+//FIXME: save entire sigaction!
+	previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
+	win_changed(0); /* get initial window size */
+
+	read_key_buffer[0] = 0;
+	while (1) {
+		/*
+		 * The emacs and vi modes share much of the code in the big
+		 * command loop.  Commands entered when in vi's command mode
+		 * (aka "escape mode") get an extra bit added to distinguish
+		 * them - this keeps them from being self-inserted. This
+		 * clutters the big switch a bit, but keeps all the code
+		 * in one place.
+		 */
+		int32_t ic, ic_raw;
+
+		fflush_all();
+		ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
+
+#if ENABLE_FEATURE_REVERSE_SEARCH
+ again:
+#endif
+#if ENABLE_FEATURE_EDITING_VI
+		newdelflag = 1;
+		if (vi_cmdmode) {
+			/* btw, since KEYCODE_xxx are all < 0, this doesn't
+			 * change ic if it contains one of them: */
+			ic |= VI_CMDMODE_BIT;
+		}
+#endif
+
+		switch (ic) {
+		case '\n':
+		case '\r':
+		vi_case('\n'|VI_CMDMODE_BIT:)
+		vi_case('\r'|VI_CMDMODE_BIT:)
+			/* Enter */
+			goto_new_line();
+			break_out = 1;
+			break;
+		case CTRL('A'):
+		vi_case('0'|VI_CMDMODE_BIT:)
+			/* Control-a -- Beginning of line */
+			input_backward(cursor);
+			break;
+		case CTRL('B'):
+		vi_case('h'|VI_CMDMODE_BIT:)
+		vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
+		vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
+			input_backward(1); /* Move back one character */
+			break;
+		case CTRL('E'):
+		vi_case('$'|VI_CMDMODE_BIT:)
+			/* Control-e -- End of line */
+			put_till_end_and_adv_cursor();
+			break;
+		case CTRL('F'):
+		vi_case('l'|VI_CMDMODE_BIT:)
+		vi_case(' '|VI_CMDMODE_BIT:)
+			input_forward(); /* Move forward one character */
+			break;
+		case '\b':   /* ^H */
+		case '\x7f': /* DEL */
+			if (!isrtl_str())
+				input_backspace();
+			else
+				input_delete(0);
+			break;
+		case KEYCODE_DELETE:
+			if (!isrtl_str())
+				input_delete(0);
+			else
+				input_backspace();
+			break;
+#if ENABLE_FEATURE_TAB_COMPLETION
+		case '\t':
+			input_tab(&lastWasTab);
+			break;
+#endif
+		case CTRL('K'):
+			/* Control-k -- clear to end of line */
+			command_ps[cursor] = BB_NUL;
+			command_len = cursor;
+			printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
+			break;
+		case CTRL('L'):
+		vi_case(CTRL('L')|VI_CMDMODE_BIT:)
+			/* Control-l -- clear screen */
+			printf(ESC"[H"); /* cursor to top,left */
+			redraw(0, command_len - cursor);
+			break;
+#if MAX_HISTORY > 0
+		case CTRL('N'):
+		vi_case(CTRL('N')|VI_CMDMODE_BIT:)
+		vi_case('j'|VI_CMDMODE_BIT:)
+			/* Control-n -- Get next command in history */
+			if (get_next_history())
+				goto rewrite_line;
+			break;
+		case CTRL('P'):
+		vi_case(CTRL('P')|VI_CMDMODE_BIT:)
+		vi_case('k'|VI_CMDMODE_BIT:)
+			/* Control-p -- Get previous command from history */
+			if (get_previous_history())
+				goto rewrite_line;
+			break;
+#endif
+		case CTRL('U'):
+		vi_case(CTRL('U')|VI_CMDMODE_BIT:)
+			/* Control-U -- Clear line before cursor */
+			if (cursor) {
+				command_len -= cursor;
+				memmove(command_ps, command_ps + cursor,
+					(command_len + 1) * sizeof(command_ps[0]));
+				redraw(cmdedit_y, command_len);
+			}
+			break;
+		case CTRL('W'):
+		vi_case(CTRL('W')|VI_CMDMODE_BIT:)
+			/* Control-W -- Remove the last word */
+			while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
+				input_backspace();
+			while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
+				input_backspace();
+			break;
+#if ENABLE_FEATURE_REVERSE_SEARCH
+		case CTRL('R'):
+			ic = ic_raw = reverse_i_search();
+			goto again;
+#endif
+
+#if ENABLE_FEATURE_EDITING_VI
+		case 'i'|VI_CMDMODE_BIT:
+			vi_cmdmode = 0;
+			break;
+		case 'I'|VI_CMDMODE_BIT:
+			input_backward(cursor);
+			vi_cmdmode = 0;
+			break;
+		case 'a'|VI_CMDMODE_BIT:
+			input_forward();
+			vi_cmdmode = 0;
+			break;
+		case 'A'|VI_CMDMODE_BIT:
+			put_till_end_and_adv_cursor();
+			vi_cmdmode = 0;
+			break;
+		case 'x'|VI_CMDMODE_BIT:
+			input_delete(1);
+			break;
+		case 'X'|VI_CMDMODE_BIT:
+			if (cursor > 0) {
+				input_backward(1);
+				input_delete(1);
+			}
+			break;
+		case 'W'|VI_CMDMODE_BIT:
+			vi_Word_motion(1);
+			break;
+		case 'w'|VI_CMDMODE_BIT:
+			vi_word_motion(1);
+			break;
+		case 'E'|VI_CMDMODE_BIT:
+			vi_End_motion();
+			break;
+		case 'e'|VI_CMDMODE_BIT:
+			vi_end_motion();
+			break;
+		case 'B'|VI_CMDMODE_BIT:
+			vi_Back_motion();
+			break;
+		case 'b'|VI_CMDMODE_BIT:
+			vi_back_motion();
+			break;
+		case 'C'|VI_CMDMODE_BIT:
+			vi_cmdmode = 0;
+			/* fall through */
+		case 'D'|VI_CMDMODE_BIT:
+			goto clear_to_eol;
+
+		case 'c'|VI_CMDMODE_BIT:
+			vi_cmdmode = 0;
+			/* fall through */
+		case 'd'|VI_CMDMODE_BIT: {
+			int nc, sc;
+
+			ic = lineedit_read_key(read_key_buffer, timeout);
+			if (errno) /* error */
+				goto return_error_indicator;
+			if (ic == ic_raw) { /* "cc", "dd" */
+				input_backward(cursor);
+				goto clear_to_eol;
+				break;
+			}
+
+			sc = cursor;
+			switch (ic) {
+			case 'w':
+			case 'W':
+			case 'e':
+			case 'E':
+				switch (ic) {
+				case 'w':   /* "dw", "cw" */
+					vi_word_motion(vi_cmdmode);
+					break;
+				case 'W':   /* 'dW', 'cW' */
+					vi_Word_motion(vi_cmdmode);
+					break;
+				case 'e':   /* 'de', 'ce' */
+					vi_end_motion();
+					input_forward();
+					break;
+				case 'E':   /* 'dE', 'cE' */
+					vi_End_motion();
+					input_forward();
+					break;
+				}
+				nc = cursor;
+				input_backward(cursor - sc);
+				while (nc-- > cursor)
+					input_delete(1);
+				break;
+			case 'b':  /* "db", "cb" */
+			case 'B':  /* implemented as B */
+				if (ic == 'b')
+					vi_back_motion();
+				else
+					vi_Back_motion();
+				while (sc-- > cursor)
+					input_delete(1);
+				break;
+			case ' ':  /* "d ", "c " */
+				input_delete(1);
+				break;
+			case '$':  /* "d$", "c$" */
+ clear_to_eol:
+				while (cursor < command_len)
+					input_delete(1);
+				break;
+			}
+			break;
+		}
+		case 'p'|VI_CMDMODE_BIT:
+			input_forward();
+			/* fallthrough */
+		case 'P'|VI_CMDMODE_BIT:
+			put();
+			break;
+		case 'r'|VI_CMDMODE_BIT:
+//FIXME: unicode case?
+			ic = lineedit_read_key(read_key_buffer, timeout);
+			if (errno) /* error */
+				goto return_error_indicator;
+			if (ic < ' ' || ic > 255) {
+				beep();
+			} else {
+				command_ps[cursor] = ic;
+				bb_putchar(ic);
+				bb_putchar('\b');
+			}
+			break;
+		case '\x1b': /* ESC */
+			if (state->flags & VI_MODE) {
+				/* insert mode --> command mode */
+				vi_cmdmode = 1;
+				input_backward(1);
+			}
+			/* Handle a few ESC-<key> combinations the same way
+			 * standard readline bindings (IOW: bash) do.
+			 * Often, Alt-<key> generates ESC-<key>.
+			 */
+			ic = lineedit_read_key(read_key_buffer, timeout);
+			switch (ic) {
+				//case KEYCODE_LEFT: - bash doesn't do this
+				case 'b':
+					ctrl_left();
+					break;
+				//case KEYCODE_RIGHT: - bash doesn't do this
+				case 'f':
+					ctrl_right();
+					break;
+				//case KEYCODE_DELETE: - bash doesn't do this
+				case 'd':  /* Alt-D */
+				{
+					/* Delete word forward */
+					int nc, sc = cursor;
+					ctrl_right();
+					nc = cursor - sc;
+					input_backward(nc);
+					while (--nc >= 0)
+						input_delete(1);
+					break;
+				}
+				case '\b':   /* Alt-Backspace(?) */
+				case '\x7f': /* Alt-Backspace(?) */
+				//case 'w': - bash doesn't do this
+				{
+					/* Delete word backward */
+					int sc = cursor;
+					ctrl_left();
+					while (sc-- > cursor)
+						input_delete(1);
+					break;
+				}
+			}
+			break;
+#endif /* FEATURE_COMMAND_EDITING_VI */
+
+#if MAX_HISTORY > 0
+		case KEYCODE_UP:
+			if (get_previous_history())
+				goto rewrite_line;
+			beep();
+			break;
+		case KEYCODE_DOWN:
+			if (!get_next_history())
+				break;
+ rewrite_line:
+			/* Rewrite the line with the selected history item */
+			/* change command */
+			command_len = load_string(state->history[state->cur_history] ?
+					state->history[state->cur_history] : "");
+			/* redraw and go to eol (bol, in vi) */
+			redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
+			break;
+#endif
+		case KEYCODE_RIGHT:
+			input_forward();
+			break;
+		case KEYCODE_LEFT:
+			input_backward(1);
+			break;
+		case KEYCODE_CTRL_LEFT:
+		case KEYCODE_ALT_LEFT: /* bash doesn't do it */
+			ctrl_left();
+			break;
+		case KEYCODE_CTRL_RIGHT:
+		case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
+			ctrl_right();
+			break;
+		case KEYCODE_HOME:
+			input_backward(cursor);
+			break;
+		case KEYCODE_END:
+			put_till_end_and_adv_cursor();
+			break;
+
+		default:
+			if (initial_settings.c_cc[VINTR] != 0
+			 && ic_raw == initial_settings.c_cc[VINTR]
+			) {
+				/* Ctrl-C (usually) - stop gathering input */
+				goto_new_line();
+				command_len = 0;
+				break_out = -1; /* "do not append '\n'" */
+				break;
+			}
+			if (initial_settings.c_cc[VEOF] != 0
+			 && ic_raw == initial_settings.c_cc[VEOF]
+			) {
+				/* Ctrl-D (usually) - delete one character,
+				 * or exit if len=0 and no chars to delete */
+				if (command_len == 0) {
+					errno = 0;
+
+		case -1: /* error (e.g. EIO when tty is destroyed) */
+ IF_FEATURE_EDITING_VI(return_error_indicator:)
+					break_out = command_len = -1;
+					break;
+				}
+				input_delete(0);
+				break;
+			}
+//			/* Control-V -- force insert of next char */
+//			if (c == CTRL('V')) {
+//				if (safe_read(STDIN_FILENO, &c, 1) < 1)
+//					goto return_error_indicator;
+//				if (c == 0) {
+//					beep();
+//					break;
+//				}
+//			}
+			if (ic < ' '
+			 || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
+			 || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
+			) {
+				/* If VI_CMDMODE_BIT is set, ic is >= 256
+				 * and vi mode ignores unexpected chars.
+				 * Otherwise, we are here if ic is a
+				 * control char or an unhandled ESC sequence,
+				 * which is also ignored.
+				 */
+				break;
+			}
+			if ((int)command_len >= (maxsize - 2)) {
+				/* Not enough space for the char and EOL */
+				break;
+			}
+
+			command_len++;
+			if (cursor == (command_len - 1)) {
+				/* We are at the end, append */
+				command_ps[cursor] = ic;
+				command_ps[cursor + 1] = BB_NUL;
+				put_cur_glyph_and_inc_cursor();
+				if (unicode_bidi_isrtl(ic))
+					input_backward(1);
+			} else {
+				/* In the middle, insert */
+				int sc = cursor;
+
+				memmove(command_ps + sc + 1, command_ps + sc,
+					(command_len - sc) * sizeof(command_ps[0]));
+				command_ps[sc] = ic;
+				/* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
+				if (!isrtl_str())
+					sc++; /* no */
+				put_till_end_and_adv_cursor();
+				/* to prev x pos + 1 */
+				input_backward(cursor - sc);
+			}
+			break;
+		} /* switch (ic) */
+
+		if (break_out)
+			break;
+
+#if ENABLE_FEATURE_TAB_COMPLETION
+		if (ic_raw != '\t')
+			lastWasTab = 0;
+#endif
+	} /* while (1) */
+
+#if ENABLE_FEATURE_EDITING_ASK_TERMINAL
+	if (S.sent_ESC_br6n) {
+		/* "sleep 1; busybox ash" + hold [Enter] to trigger.
+		 * We sent "ESC [ 6 n", but got '\n' first, and
+		 * KEYCODE_CURSOR_POS response is now buffered from terminal.
+		 * It's bad already and not much can be done with it
+		 * (it _will_ be visible for the next process to read stdin),
+		 * but without this delay it even shows up on the screen
+		 * as garbage because we restore echo settings with tcsetattr
+		 * before it comes in. UGLY!
+		 */
+		usleep(20*1000);
+	}
+#endif
+
+/* End of bug-catching "command_must_not_be_used" trick */
+#undef command
+
+#if ENABLE_UNICODE_SUPPORT
+	command[0] = '\0';
+	if (command_len > 0)
+		command_len = save_string(command, maxsize - 1);
+	free(command_ps);
+#endif
+
+	if (command_len > 0)
+		remember_in_history(command);
+
+	if (break_out > 0) {
+		command[command_len++] = '\n';
+		command[command_len] = '\0';
+	}
+
+#if ENABLE_FEATURE_TAB_COMPLETION
+	free_tab_completion_data();
+#endif
+
+	/* restore initial_settings */
+	tcsetattr_stdin_TCSANOW(&initial_settings);
+	/* restore SIGWINCH handler */
+	signal(SIGWINCH, previous_SIGWINCH_handler);
+	fflush_all();
+
+	len = command_len;
+	DEINIT_S();
+
+	return len; /* can't return command_len, DEINIT_S() destroys it */
+}
+
+#else  /* !FEATURE_EDITING */
+
+#undef read_line_input
+int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
+{
+	fputs(prompt, stdout);
+	fflush_all();
+	if (!fgets(command, maxsize, stdin))
+		return -1;
+	return strlen(command);
+}
+
+#endif  /* !FEATURE_EDITING */
+
+
+/*
+ * Testing
+ */
+
+#ifdef TEST
+
+#include <locale.h>
+
+const char *applet_name = "debug stuff usage";
+
+int main(int argc, char **argv)
+{
+	char buff[MAX_LINELEN];
+	char *prompt =
+#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+		"\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
+		"\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
+		"\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
+#else
+		"% ";
+#endif
+
+	while (1) {
+		int l;
+		l = read_line_input(prompt, buff);
+		if (l <= 0 || buff[l-1] != '\n')
+			break;
+		buff[l-1] = '\0';
+		printf("*** read_line_input() returned line =%s=\n", buff);
+	}
+	printf("*** read_line_input() detect ^D\n");
+	return 0;
+}
+
+#endif  /* TEST */