+
−/* Determine the number of screen columns needed for a string.
+
−   Copyright (C) 2000-2012 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
−
+
−/* Written by Bruno Haible <haible@clisp.cons.org>.  */
+
−
+
−#include <config.h>
+
−
+
−/* 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().  */
+
−#include <wchar.h>
+
−
+
−/* Get iswcntrl().  */
+
−#include <wctype.h>
+
−
+
−/* Get INT_MAX.  */
+
−#include <limits.h>
+
−
+
−/* 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.  */
+
−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.  */
+
−int
+
−mbsnwidth (const char *string, size_t nbytes, int flags)
+
−{
+
−  const char *p = string;
+
−  const char *plimit = p + nbytes;
+
−  int width;
+
−
+
−  width = 0;
+
−  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.  */
+
−                      {
+
−                        if (w > INT_MAX - width)
+
−                          goto overflow;
+
−                        width += w;
+
−                      }
+
−                    else
+
−                      /* An unprintable multibyte character.  */
+
−                      if (!(flags & MBSW_REJECT_UNPRINTABLE))
+
−                        {
+
−                          if (!iswcntrl (wc))
+
−                            {
+
−                              if (width == INT_MAX)
+
−                                goto overflow;
+
−                              width++;
+
−                            }
+
−                        }
+
−                      else
+
−                        return -1;
+
−
+
−                    p += bytes;
+
−                  }
+
−                while (! mbsinit (&mbstate));
+
−              }
+
−              break;
+
−          }
+
−      return width;
+
−    }
+
−
+
−  while (p < plimit)
+
−    {
+
−      unsigned char c = (unsigned char) *p++;
+
−
+
−      if (isprint (c))
+
−        {
+
−          if (width == INT_MAX)
+
−            goto overflow;
+
−          width++;
+
−        }
+
−      else if (!(flags & MBSW_REJECT_UNPRINTABLE))
+
−        {
+
−          if (!iscntrl (c))
+
−            {
+
−              if (width == INT_MAX)
+
−                goto overflow;
+
−              width++;
+
−            }
+
−        }
+
−      else
+
−        return -1;
+
−    }
+
−  return width;
+
−
+
− overflow:
+
−  return INT_MAX;
+
−}