utf8.c - tmux - Rivoreo Source Code Repositories

 /* $OpenBSD$ */

 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #include <sys/types.h>

 #include <ctype.h>
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
 #include <wchar.h>

 #include "tmux.h"

 static int	utf8_width(wchar_t);

 /* Set a single character. */
 void
 utf8_set(struct utf8_data *ud, u_char ch)
 {
 	static const struct utf8_data empty = { { 0 }, 1, 1, 1 };

 	memcpy(ud, &empty, sizeof *ud);
 	*ud->data = ch;
 }

 /* Copy UTF-8 character. */
 void
 utf8_copy(struct utf8_data *to, const struct utf8_data *from)
 {
 	u_int	i;

 	memcpy(to, from, sizeof *to);

 	for (i = to->size; i < sizeof to->data; i++)
 		to->data[i] = '\0';
 }

 /*
  * Open UTF-8 sequence.
  *
  * 11000010-11011111 C2-DF start of 2-byte sequence
  * 11100000-11101111 E0-EF start of 3-byte sequence
  * 11110000-11110100 F0-F4 start of 4-byte sequence
  */
 enum utf8_state
 utf8_open(struct utf8_data *ud, u_char ch)
 {
 	memset(ud, 0, sizeof *ud);
 	if (ch >= 0xc2 && ch <= 0xdf)
 		ud->size = 2;
 	else if (ch >= 0xe0 && ch <= 0xef)
 		ud->size = 3;
 	else if (ch >= 0xf0 && ch <= 0xf4)
 		ud->size = 4;
 	else
 		return (UTF8_ERROR);
 	utf8_append(ud, ch);
 	return (UTF8_MORE);
 }

 /* Append character to UTF-8, closing if finished. */
 enum utf8_state
 utf8_append(struct utf8_data *ud, u_char ch)
 {
 	wchar_t	wc;
 	int	width;

 	if (ud->have >= ud->size)
 		fatalx("UTF-8 character overflow");
 	if (ud->size > sizeof ud->data)
 		fatalx("UTF-8 character size too large");

 	if (ud->have != 0 && (ch & 0xc0) != 0x80)
 		ud->width = 0xff;

 	ud->data[ud->have++] = ch;
 	if (ud->have != ud->size)
 		return (UTF8_MORE);

 	if (ud->width == 0xff)
 		return (UTF8_ERROR);

 	if (utf8_combine(ud, &wc) != UTF8_DONE)
 		return (UTF8_ERROR);
 	if ((width = utf8_width(wc)) < 0)
 		return (UTF8_ERROR);
 	ud->width = width;

 	return (UTF8_DONE);
 }

 /* Get width of Unicode character. */
 static int
 utf8_width(wchar_t wc)
 {
 	int	width;

 #ifdef HAVE_UTF8PROC
 	width = utf8proc_wcwidth(wc);
 #else
 	width = wcwidth(wc);
 #endif
 	if (width < 0 || width > 0xff) {
 		log_debug("Unicode %04lx, wcwidth() %d", (long)wc, width);

 #ifndef __OpenBSD__
 		/*
 		 * Many platforms (particularly and inevitably OS X) have no
 		 * width for relatively common characters (wcwidth() returns
 		 * -1); assume width 1 in this case. This will be wrong for
 		 * genuinely nonprintable characters, but they should be
 		 * rare. We may pass through stuff that ideally we would block,
 		 * but this is no worse than sending the same to the terminal
 		 * without tmux.
 		 */
 		if (width < 0)
 			return (1);
 #endif
 		return (-1);
 	}
 	return (width);
 }

 /* Combine UTF-8 into Unicode. */
 enum utf8_state
 utf8_combine(const struct utf8_data *ud, wchar_t *wc)
 {
 #ifdef HAVE_UTF8PROC
 	switch (utf8proc_mbtowc(wc, ud->data, ud->size)) {
 #else
 	switch (mbtowc(wc, ud->data, ud->size)) {
 #endif
 	case -1:
 		log_debug("UTF-8 %.*s, mbtowc() %d", (int)ud->size, ud->data,
 		    errno);
 		mbtowc(NULL, NULL, MB_CUR_MAX);
 		return (UTF8_ERROR);
 	case 0:
 		return (UTF8_ERROR);
 	default:
 		return (UTF8_DONE);
 	}
 }

 /* Split Unicode into UTF-8. */
 enum utf8_state
 utf8_split(wchar_t wc, struct utf8_data *ud)
 {
 	char	s[MB_LEN_MAX];
 	int	slen;

 #ifdef HAVE_UTF8PROC
 	slen = utf8proc_wctomb(s, wc);
 #else
 	slen = wctomb(s, wc);
 #endif
 	if (slen <= 0 || slen > (int)sizeof ud->data)
 		return (UTF8_ERROR);

 	memcpy(ud->data, s, slen);
 	ud->size = slen;

 	ud->width = utf8_width(wc);
 	return (UTF8_DONE);
 }

 /*
  * Encode len characters from src into dst, which is guaranteed to have four
  * bytes available for each character from src (for \abc or UTF-8) plus space
  * for \0.
  */
 int
 utf8_strvis(char *dst, const char *src, size_t len, int flag)
 {
 	struct utf8_data	 ud;
 	const char		*start, *end;
 	enum utf8_state		 more;
 	size_t			 i;

 	start = dst;
 	end = src + len;

 	while (src < end) {
 		if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
 			while (++src < end && more == UTF8_MORE)
 				more = utf8_append(&ud, *src);
 			if (more == UTF8_DONE) {
 				/* UTF-8 character finished. */
 				for (i = 0; i < ud.size; i++)
 					*dst++ = ud.data[i];
 				continue;
 			}
 			/* Not a complete, valid UTF-8 character. */
 			src -= ud.have;
 		}
 		if (src[0] == '$' && src < end - 1) {
 			if (isalpha((u_char)src[1]) || src[1] == '_')
 				*dst++ = '\\';
 			*dst++ = '$';
 		} else if (src < end - 1)
 			dst = vis(dst, src[0], flag, src[1]);
 		else if (src < end)
 			dst = vis(dst, src[0], flag, '\0');
 		src++;
 	}

 	*dst = '\0';
 	return (dst - start);
 }

 /* Same as utf8_strvis but allocate the buffer. */
 int
 utf8_stravis(char **dst, const char *src, int flag)
 {
 	char	*buf;
 	int	 len;

 	buf = xreallocarray(NULL, 4, strlen(src) + 1);
 	len = utf8_strvis(buf, src, strlen(src), flag);

 	*dst = xrealloc(buf, len + 1);
 	return (len);
 }

 /* Does this string contain anything that isn't valid UTF-8? */
 int
 utf8_isvalid(const char *s)
 {
 	struct utf8_data	 ud;
 	const char		*end;
 	enum utf8_state		 more;

 	end = s + strlen(s);
 	while (s < end) {
 		if ((more = utf8_open(&ud, *s)) == UTF8_MORE) {
 			while (++s < end && more == UTF8_MORE)
 				more = utf8_append(&ud, *s);
 			if (more == UTF8_DONE)
 				continue;
 			return (0);
 		}
 		if (*s < 0x20 || *s > 0x7e)
 			return (0);
 		s++;
 	}
 	return (1);
 }

 /*
  * Sanitize a string, changing any UTF-8 characters to '_'. Caller should free
  * the returned string. Anything not valid printable ASCII or UTF-8 is
  * stripped.
  */
 char *
 utf8_sanitize(const char *src)
 {
 	char			*dst;
 	size_t			 n;
 	enum utf8_state		 more;
 	struct utf8_data	 ud;
 	u_int			 i;

 	dst = NULL;

 	n = 0;
 	while (*src != '\0') {
 		dst = xreallocarray(dst, n + 1, sizeof *dst);
 		if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
 			while (*++src != '\0' && more == UTF8_MORE)
 				more = utf8_append(&ud, *src);
 			if (more == UTF8_DONE) {
 				dst = xreallocarray(dst, n + ud.width,
 				    sizeof *dst);
 				for (i = 0; i < ud.width; i++)
 					dst[n++] = '_';
 				continue;
 			}
 			src -= ud.have;
 		}
 		if (*src > 0x1f && *src < 0x7f)
 			dst[n++] = *src;
 		else
 			dst[n++] = '_';
 		src++;
 	}

 	dst = xreallocarray(dst, n + 1, sizeof *dst);
 	dst[n] = '\0';
 	return (dst);
 }

 /* Get UTF-8 buffer length. */
 size_t
 utf8_strlen(const struct utf8_data *s)
 {
 	size_t	i;

 	for (i = 0; s[i].size != 0; i++)
 		/* nothing */;
 	return (i);
 }

 /* Get UTF-8 string width. */
 u_int
 utf8_strwidth(const struct utf8_data *s, ssize_t n)
 {
 	ssize_t	i;
 	u_int	width;

 	width = 0;
 	for (i = 0; s[i].size != 0; i++) {
 		if (n != -1 && n == i)
 			break;
 		width += s[i].width;
 	}
 	return (width);
 }

 /*
  * Convert a string into a buffer of UTF-8 characters. Terminated by size == 0.
  * Caller frees.
  */
 struct utf8_data *
 utf8_fromcstr(const char *src)
 {
 	struct utf8_data	*dst;
 	size_t			 n;
 	enum utf8_state		 more;

 	dst = NULL;

 	n = 0;
 	while (*src != '\0') {
 		dst = xreallocarray(dst, n + 1, sizeof *dst);
 		if ((more = utf8_open(&dst[n], *src)) == UTF8_MORE) {
 			while (*++src != '\0' && more == UTF8_MORE)
 				more = utf8_append(&dst[n], *src);
 			if (more == UTF8_DONE) {
 				n++;
 				continue;
 			}
 			src -= dst[n].have;
 		}
 		utf8_set(&dst[n], *src);
 		n++;
 		src++;
 	}

 	dst = xreallocarray(dst, n + 1, sizeof *dst);
 	dst[n].size = 0;
 	return (dst);
 }

 /* Convert from a buffer of UTF-8 characters into a string. Caller frees. */
 char *
 utf8_tocstr(struct utf8_data *src)
 {
 	char	*dst;
 	size_t	 n;

 	dst = NULL;

 	n = 0;
 	for(; src->size != 0; src++) {
 		dst = xreallocarray(dst, n + src->size, 1);
 		memcpy(dst + n, src->data, src->size);
 		n += src->size;
 	}

 	dst = xreallocarray(dst, n + 1, 1);
 	dst[n] = '\0';
 	return (dst);
 }

 /* Get width of UTF-8 string. */
 u_int
 utf8_cstrwidth(const char *s)
 {
 	struct utf8_data	tmp;
 	u_int			width;
 	enum utf8_state		more;

 	width = 0;
 	while (*s != '\0') {
 		if ((more = utf8_open(&tmp, *s)) == UTF8_MORE) {
 			while (*++s != '\0' && more == UTF8_MORE)
 				more = utf8_append(&tmp, *s);
 			if (more == UTF8_DONE) {
 				width += tmp.width;
 				continue;
 			}
 			s -= tmp.have;
 		}
 		if (*s > 0x1f && *s != 0x7f)
 			width++;
 		s++;
 	}
 	return (width);
 }

 /* Pad UTF-8 string to width. Caller frees. */
 char *
 utf8_padcstr(const char *s, u_int width)
 {
 	size_t	 slen;
 	char	*out;
 	u_int	  n, i;

 	n = utf8_cstrwidth(s);
 	if (n >= width)
 		return (xstrdup(s));

 	slen = strlen(s);
 	out = xmalloc(slen + 1 + (width - n));
 	memcpy(out, s, slen);
 	for (i = n; i < width; i++)
 		out[slen++] = ' ';
 	out[slen] = '\0';
 	return (out);
 }
	/* $OpenBSD$ */

	/*
	* Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
	*
	* Permission to use, copy, modify, and distribute this software for any
	* purpose with or without fee is hereby granted, provided that the above
	* copyright notice and this permission notice appear in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
	* IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
	* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#include <sys/types.h>

	#include <ctype.h>
	#include <errno.h>
	#include <stdlib.h>
	#include <string.h>
	#include <wchar.h>

	#include "tmux.h"

	static int utf8_width(wchar_t);

	/* Set a single character. */
	void
	utf8_set(struct utf8_data *ud, u_char ch)
	{
	static const struct utf8_data empty = { { 0 }, 1, 1, 1 };

	memcpy(ud, &empty, sizeof *ud);
	*ud->data = ch;
	}

	/* Copy UTF-8 character. */
	void
	utf8_copy(struct utf8_data to, const struct utf8_data from)
	{
	u_int i;

	memcpy(to, from, sizeof *to);

	for (i = to->size; i < sizeof to->data; i++)
	to->data[i] = '\0';
	}

	/*
	* Open UTF-8 sequence.
	*
	* 11000010-11011111 C2-DF start of 2-byte sequence
	* 11100000-11101111 E0-EF start of 3-byte sequence
	* 11110000-11110100 F0-F4 start of 4-byte sequence
	*/
	enum utf8_state
	utf8_open(struct utf8_data *ud, u_char ch)
	{
	memset(ud, 0, sizeof *ud);
	if (ch >= 0xc2 && ch <= 0xdf)
	ud->size = 2;
	else if (ch >= 0xe0 && ch <= 0xef)
	ud->size = 3;
	else if (ch >= 0xf0 && ch <= 0xf4)
	ud->size = 4;
	else
	return (UTF8_ERROR);
	utf8_append(ud, ch);
	return (UTF8_MORE);
	}

	/* Append character to UTF-8, closing if finished. */
	enum utf8_state
	utf8_append(struct utf8_data *ud, u_char ch)
	{
	wchar_t wc;
	int width;

	if (ud->have >= ud->size)
	fatalx("UTF-8 character overflow");
	if (ud->size > sizeof ud->data)
	fatalx("UTF-8 character size too large");

	if (ud->have != 0 && (ch & 0xc0) != 0x80)
	ud->width = 0xff;

	ud->data[ud->have++] = ch;
	if (ud->have != ud->size)
	return (UTF8_MORE);

	if (ud->width == 0xff)
	return (UTF8_ERROR);

	if (utf8_combine(ud, &wc) != UTF8_DONE)
	return (UTF8_ERROR);
	if ((width = utf8_width(wc)) < 0)
	return (UTF8_ERROR);
	ud->width = width;

	return (UTF8_DONE);
	}

	/* Get width of Unicode character. */
	static int
	utf8_width(wchar_t wc)
	{
	int width;

	#ifdef HAVE_UTF8PROC
	width = utf8proc_wcwidth(wc);
	#else
	width = wcwidth(wc);
	#endif
	if (width < 0 \|\| width > 0xff) {
	log_debug("Unicode %04lx, wcwidth() %d", (long)wc, width);

	#ifndef __OpenBSD__
	/*
	* Many platforms (particularly and inevitably OS X) have no
	* width for relatively common characters (wcwidth() returns
	* -1); assume width 1 in this case. This will be wrong for
	* genuinely nonprintable characters, but they should be
	* rare. We may pass through stuff that ideally we would block,
	* but this is no worse than sending the same to the terminal
	* without tmux.
	*/
	if (width < 0)
	return (1);
	#endif
	return (-1);
	}
	return (width);
	}

	/* Combine UTF-8 into Unicode. */
	enum utf8_state
	utf8_combine(const struct utf8_data ud, wchar_t wc)
	{
	#ifdef HAVE_UTF8PROC
	switch (utf8proc_mbtowc(wc, ud->data, ud->size)) {
	#else
	switch (mbtowc(wc, ud->data, ud->size)) {
	#endif
	case -1:
	log_debug("UTF-8 %.*s, mbtowc() %d", (int)ud->size, ud->data,
	errno);
	mbtowc(NULL, NULL, MB_CUR_MAX);
	return (UTF8_ERROR);
	case 0:
	return (UTF8_ERROR);
	default:
	return (UTF8_DONE);
	}
	}

	/* Split Unicode into UTF-8. */
	enum utf8_state
	utf8_split(wchar_t wc, struct utf8_data *ud)
	{
	char s[MB_LEN_MAX];
	int slen;

	#ifdef HAVE_UTF8PROC
	slen = utf8proc_wctomb(s, wc);
	#else
	slen = wctomb(s, wc);
	#endif
	if (slen <= 0 \|\| slen > (int)sizeof ud->data)
	return (UTF8_ERROR);

	memcpy(ud->data, s, slen);
	ud->size = slen;

	ud->width = utf8_width(wc);
	return (UTF8_DONE);
	}

	/*
	* Encode len characters from src into dst, which is guaranteed to have four
	* bytes available for each character from src (for \abc or UTF-8) plus space
	* for \0.
	*/
	int
	utf8_strvis(char dst, const char src, size_t len, int flag)
	{
	struct utf8_data ud;
	const char start, end;
	enum utf8_state more;
	size_t i;

	start = dst;
	end = src + len;

	while (src < end) {
	if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
	while (++src < end && more == UTF8_MORE)
	more = utf8_append(&ud, *src);
	if (more == UTF8_DONE) {
	/* UTF-8 character finished. */
	for (i = 0; i < ud.size; i++)
	*dst++ = ud.data[i];
	continue;
	}
	/* Not a complete, valid UTF-8 character. */
	src -= ud.have;
	}
	if (src[0] == '$' && src < end - 1) {
	if (isalpha((u_char)src[1]) \|\| src[1] == '_')
	*dst++ = '\\';
	*dst++ = '$';
	} else if (src < end - 1)
	dst = vis(dst, src[0], flag, src[1]);
	else if (src < end)
	dst = vis(dst, src[0], flag, '\0');
	src++;
	}

	*dst = '\0';
	return (dst - start);
	}

	/* Same as utf8_strvis but allocate the buffer. */
	int
	utf8_stravis(char *dst, const char src, int flag)
	{
	char *buf;
	int len;

	buf = xreallocarray(NULL, 4, strlen(src) + 1);
	len = utf8_strvis(buf, src, strlen(src), flag);

	*dst = xrealloc(buf, len + 1);
	return (len);
	}

	/* Does this string contain anything that isn't valid UTF-8? */
	int
	utf8_isvalid(const char *s)
	{
	struct utf8_data ud;
	const char *end;
	enum utf8_state more;

	end = s + strlen(s);
	while (s < end) {
	if ((more = utf8_open(&ud, *s)) == UTF8_MORE) {
	while (++s < end && more == UTF8_MORE)
	more = utf8_append(&ud, *s);
	if (more == UTF8_DONE)
	continue;
	return (0);
	}
	if (s < 0x20 \|\| s > 0x7e)
	return (0);
	s++;
	}
	return (1);
	}

	/*
	* Sanitize a string, changing any UTF-8 characters to '_'. Caller should free
	* the returned string. Anything not valid printable ASCII or UTF-8 is
	* stripped.
	*/
	char *
	utf8_sanitize(const char *src)
	{
	char *dst;
	size_t n;
	enum utf8_state more;
	struct utf8_data ud;
	u_int i;

	dst = NULL;

	n = 0;
	while (*src != '\0') {
	dst = xreallocarray(dst, n + 1, sizeof *dst);
	if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
	while (*++src != '\0' && more == UTF8_MORE)
	more = utf8_append(&ud, *src);
	if (more == UTF8_DONE) {
	dst = xreallocarray(dst, n + ud.width,
	sizeof *dst);
	for (i = 0; i < ud.width; i++)
	dst[n++] = '_';
	continue;
	}
	src -= ud.have;
	}
	if (src > 0x1f && src < 0x7f)
	dst[n++] = *src;
	else
	dst[n++] = '_';
	src++;
	}

	dst = xreallocarray(dst, n + 1, sizeof *dst);
	dst[n] = '\0';
	return (dst);
	}

	/* Get UTF-8 buffer length. */
	size_t
	utf8_strlen(const struct utf8_data *s)
	{
	size_t i;

	for (i = 0; s[i].size != 0; i++)
	/* nothing */;
	return (i);
	}

	/* Get UTF-8 string width. */
	u_int
	utf8_strwidth(const struct utf8_data *s, ssize_t n)
	{
	ssize_t i;
	u_int width;

	width = 0;
	for (i = 0; s[i].size != 0; i++) {
	if (n != -1 && n == i)
	break;
	width += s[i].width;
	}
	return (width);
	}

	/*
	* Convert a string into a buffer of UTF-8 characters. Terminated by size == 0.
	* Caller frees.
	*/
	struct utf8_data *
	utf8_fromcstr(const char *src)
	{
	struct utf8_data *dst;
	size_t n;
	enum utf8_state more;

	dst = NULL;

	n = 0;
	while (*src != '\0') {
	dst = xreallocarray(dst, n + 1, sizeof *dst);
	if ((more = utf8_open(&dst[n], *src)) == UTF8_MORE) {
	while (*++src != '\0' && more == UTF8_MORE)
	more = utf8_append(&dst[n], *src);
	if (more == UTF8_DONE) {
	n++;
	continue;
	}
	src -= dst[n].have;
	}
	utf8_set(&dst[n], *src);
	n++;
	src++;
	}

	dst = xreallocarray(dst, n + 1, sizeof *dst);
	dst[n].size = 0;
	return (dst);
	}

	/* Convert from a buffer of UTF-8 characters into a string. Caller frees. */
	char *
	utf8_tocstr(struct utf8_data *src)
	{
	char *dst;
	size_t n;

	dst = NULL;

	n = 0;
	for(; src->size != 0; src++) {
	dst = xreallocarray(dst, n + src->size, 1);
	memcpy(dst + n, src->data, src->size);
	n += src->size;
	}

	dst = xreallocarray(dst, n + 1, 1);
	dst[n] = '\0';
	return (dst);
	}

	/* Get width of UTF-8 string. */
	u_int
	utf8_cstrwidth(const char *s)
	{
	struct utf8_data tmp;
	u_int width;
	enum utf8_state more;

	width = 0;
	while (*s != '\0') {
	if ((more = utf8_open(&tmp, *s)) == UTF8_MORE) {
	while (*++s != '\0' && more == UTF8_MORE)
	more = utf8_append(&tmp, *s);
	if (more == UTF8_DONE) {
	width += tmp.width;
	continue;
	}
	s -= tmp.have;
	}
	if (s > 0x1f && s != 0x7f)
	width++;
	s++;
	}
	return (width);
	}

	/* Pad UTF-8 string to width. Caller frees. */
	char *
	utf8_padcstr(const char *s, u_int width)
	{
	size_t slen;
	char *out;
	u_int n, i;

	n = utf8_cstrwidth(s);
	if (n >= width)
	return (xstrdup(s));

	slen = strlen(s);
	out = xmalloc(slen + 1 + (width - n));
	memcpy(out, s, slen);
	for (i = n; i < width; i++)
	out[slen++] = ' ';
	out[slen] = '\0';
	return (out);
	}