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Diffstat (limited to 'lib/mbswidth.c')
| -rw-r--r-- | lib/mbswidth.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/lib/mbswidth.c b/lib/mbswidth.c new file mode 100644 index 00000000..c9e78d65 --- /dev/null +++ b/lib/mbswidth.c @@ -0,0 +1,221 @@ +/* Determine the number of screen columns needed for a string. + Copyright (C) 2000-2005 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by Bruno Haible <haible@clisp.cons.org>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +/* Specification. */ +#include "mbswidth.h" + +/* Get MB_CUR_MAX. */ +#include <stdlib.h> + +#include <string.h> + +/* Get isprint(). */ +#include <ctype.h> + +/* Get mbstate_t, mbrtowc(), mbsinit(), wcwidth(). */ +#if HAVE_WCHAR_H +/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before + <wchar.h>. + BSD/OS 4.1 has a bug: <stdio.h> and <time.h> must be included before + <wchar.h>. */ +# include <stdio.h> +# include <time.h> +# include <wchar.h> +#endif + +/* Get iswprint(), iswcntrl(). */ +#if HAVE_WCTYPE_H +# include <wctype.h> +#endif +#if !defined iswprint && !HAVE_ISWPRINT +# define iswprint(wc) 1 +#endif +#if !defined iswcntrl && !HAVE_ISWCNTRL +# define iswcntrl(wc) 0 +#endif + +#ifndef mbsinit +# if !HAVE_MBSINIT +# define mbsinit(ps) 1 +# endif +#endif + +#ifndef HAVE_DECL_WCWIDTH +"this configure-time declaration test was not run" +#endif +#if !HAVE_DECL_WCWIDTH +int wcwidth (); +#endif + +#ifndef wcwidth +# if !HAVE_WCWIDTH +/* wcwidth doesn't exist, so assume all printable characters have + width 1. */ +# define wcwidth(wc) ((wc) == 0 ? 0 : iswprint (wc) ? 1 : -1) +# endif +#endif + +/* Get ISPRINT. */ +#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII)) +# define IN_CTYPE_DOMAIN(c) 1 +#else +# define IN_CTYPE_DOMAIN(c) isascii(c) +#endif +/* Undefine to protect against the definition in wctype.h of Solaris 2.6. */ +#undef ISPRINT +#define ISPRINT(c) (IN_CTYPE_DOMAIN (c) && isprint (c)) +#undef ISCNTRL +#define ISCNTRL(c) (IN_CTYPE_DOMAIN (c) && iscntrl (c)) + +/* Returns the number of columns needed to represent the multibyte + character string pointed to by STRING. If a non-printable character + occurs, and MBSW_REJECT_UNPRINTABLE is specified, -1 is returned. + With flags = MBSW_REJECT_INVALID | MBSW_REJECT_UNPRINTABLE, this is + the multibyte analogue of the wcswidth function. + If STRING is not of length < INT_MAX / 2, integer overflow can occur. */ +int +mbswidth (const char *string, int flags) +{ + return mbsnwidth (string, strlen (string), flags); +} + +/* Returns the number of columns needed to represent the multibyte + character string pointed to by STRING of length NBYTES. If a + non-printable character occurs, and MBSW_REJECT_UNPRINTABLE is + specified, -1 is returned. + If NBYTES is not < INT_MAX / 2, integer overflow can occur. */ +int +mbsnwidth (const char *string, size_t nbytes, int flags) +{ + const char *p = string; + const char *plimit = p + nbytes; + int width; + + width = 0; +#if HAVE_MBRTOWC + if (MB_CUR_MAX > 1) + { + while (p < plimit) + switch (*p) + { + case ' ': case '!': case '"': case '#': case '%': + case '&': case '\'': case '(': case ')': case '*': + case '+': case ',': case '-': case '.': case '/': + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + case ':': case ';': case '<': case '=': case '>': + case '?': + case 'A': case 'B': case 'C': case 'D': case 'E': + case 'F': case 'G': case 'H': case 'I': case 'J': + case 'K': case 'L': case 'M': case 'N': case 'O': + case 'P': case 'Q': case 'R': case 'S': case 'T': + case 'U': case 'V': case 'W': case 'X': case 'Y': + case 'Z': + case '[': case '\\': case ']': case '^': case '_': + case 'a': case 'b': case 'c': case 'd': case 'e': + case 'f': case 'g': case 'h': case 'i': case 'j': + case 'k': case 'l': case 'm': case 'n': case 'o': + case 'p': case 'q': case 'r': case 's': case 't': + case 'u': case 'v': case 'w': case 'x': case 'y': + case 'z': case '{': case '|': case '}': case '~': + /* These characters are printable ASCII characters. */ + p++; + width++; + break; + default: + /* If we have a multibyte sequence, scan it up to its end. */ + { + mbstate_t mbstate; + memset (&mbstate, 0, sizeof mbstate); + do + { + wchar_t wc; + size_t bytes; + int w; + + bytes = mbrtowc (&wc, p, plimit - p, &mbstate); + + if (bytes == (size_t) -1) + /* An invalid multibyte sequence was encountered. */ + { + if (!(flags & MBSW_REJECT_INVALID)) + { + p++; + width++; + break; + } + else + return -1; + } + + if (bytes == (size_t) -2) + /* An incomplete multibyte character at the end. */ + { + if (!(flags & MBSW_REJECT_INVALID)) + { + p = plimit; + width++; + break; + } + else + return -1; + } + + if (bytes == 0) + /* A null wide character was encountered. */ + bytes = 1; + + w = wcwidth (wc); + if (w >= 0) + /* A printable multibyte character. */ + width += w; + else + /* An unprintable multibyte character. */ + if (!(flags & MBSW_REJECT_UNPRINTABLE)) + width += (iswcntrl (wc) ? 0 : 1); + else + return -1; + + p += bytes; + } + while (! mbsinit (&mbstate)); + } + break; + } + return width; + } +#endif + + while (p < plimit) + { + unsigned char c = (unsigned char) *p++; + + if (ISPRINT (c)) + width++; + else if (!(flags & MBSW_REJECT_UNPRINTABLE)) + width += (ISCNTRL (c) ? 0 : 1); + else + return -1; + } + return width; +} |