/* Determine the number of screen columns needed for a string. Copyright (C) 2000-2013 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 . */ /* Written by Bruno Haible . */ #include /* Specification. */ #include "mbswidth.h" /* Get MB_CUR_MAX. */ #include #include /* Get isprint(). */ #include /* Get mbstate_t, mbrtowc(), mbsinit(), wcwidth(). */ #include /* Get iswcntrl(). */ #include /* Get INT_MAX. */ #include /* 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; case '\0': if (flags & MBSW_STOP_AT_NUL) return width; 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 (c == 0 && (flags & MBSW_STOP_AT_NUL)) return width; 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; }