lib/mbchar.h

   1 /* Multibyte character data type.
   2    Copyright (C) 2001, 2005-2006 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by Bruno Haible <bruno@clisp.org>.  */
  19
  20 /* A multibyte character is a short subsequence of a char* string,
  21    representing a single wide character.
  22
  23    We use multibyte characters instead of wide characters because of
  24    the following goals:
  25    1) correct multibyte handling, i.e. operate according to the LC_CTYPE
  26       locale,
  27    2) ease of maintenance, i.e. the maintainer needs not know all details
  28       of the ISO C 99 standard,
  29    3) don't fail grossly if the input is not in the encoding set by the
  30       locale, because often different encodings are in use in the same
  31       countries (ISO-8859-1/UTF-8, EUC-JP/Shift_JIS, ...),
  32    4) fast in the case of ASCII characters,
  33    5) portability, i.e. don't make unportable assumptions about wchar_t.
  34
  35    Multibyte characters are only accessed through the mb* macros.
  36
  37    mb_ptr (mbc)
  38      return a pointer to the beginning of the multibyte sequence.
  39
  40    mb_len (mbc)
  41      returns the number of bytes occupied by the multibyte sequence.
  42      Always > 0.
  43
  44    mb_iseq (mbc, sc)
  45      returns true if mbc is the standard ASCII character sc.
  46
  47    mb_isnul (mbc)
  48      returns true if mbc is the nul character.
  49
  50    mb_cmp (mbc1, mbc2)
  51      returns a positive, zero, or negative value depending on whether mbc1
  52      sorts after, same or before mbc2.
  53
  54    mb_casecmp (mbc1, mbc2)
  55      returns a positive, zero, or negative value depending on whether mbc1
  56      sorts after, same or before mbc2, modulo upper/lowercase conversion.
  57
  58    mb_equal (mbc1, mbc2)
  59      returns true if mbc1 and mbc2 are equal.
  60
  61    mb_caseequal (mbc1, mbc2)
  62      returns true if mbc1 and mbc2 are equal modulo upper/lowercase conversion.
  63
  64    mb_isalnum (mbc)
  65      returns true if mbc is alphanumeric.
  66
  67    mb_isalpha (mbc)
  68      returns true if mbc is alphabetic.
  69
  70    mb_isascii(mbc)
  71      returns true if mbc is plain ASCII.
  72
  73    mb_isblank (mbc)
  74      returns true if mbc is a blank.
  75
  76    mb_iscntrl (mbc)
  77      returns true if mbc is a control character.
  78
  79    mb_isdigit (mbc)
  80      returns true if mbc is a decimal digit.
  81
  82    mb_isgraph (mbc)
  83      returns true if mbc is a graphic character.
  84
  85    mb_islower (mbc)
  86      returns true if mbc is lowercase.
  87
  88    mb_isprint (mbc)
  89      returns true if mbc is a printable character.
  90
  91    mb_ispunct (mbc)
  92      returns true if mbc is a punctuation character.
  93
  94    mb_isspace (mbc)
  95      returns true if mbc is a space character.
  96
  97    mb_isupper (mbc)
  98      returns true if mbc is uppercase.
  99
 100    mb_isxdigit (mbc)
 101      returns true if mbc is a hexadecimal digit.
 102
 103    mb_width (mbc)
 104      returns the number of columns on the output device occupied by mbc.
 105      Always >= 0.
 106
 107    mb_putc (mbc, stream)
 108      outputs mbc on stream, a byte oriented FILE stream opened for output.
 109
 110    mb_setascii (&mbc, sc)
 111      assigns the standard ASCII character sc to mbc.
 112
 113    mb_copy (&destmbc, &srcmbc)
 114      copies srcmbc to destmbc.
 115
 116    Here are the function prototypes of the macros.
 117
 118    extern const char *  mb_ptr (const mbchar_t mbc);
 119    extern size_t        mb_len (const mbchar_t mbc);
 120    extern bool          mb_iseq (const mbchar_t mbc, char sc);
 121    extern bool          mb_isnul (const mbchar_t mbc);
 122    extern int           mb_cmp (const mbchar_t mbc1, const mbchar_t mbc2);
 123    extern int           mb_casecmp (const mbchar_t mbc1, const mbchar_t mbc2);
 124    extern bool          mb_equal (const mbchar_t mbc1, const mbchar_t mbc2);
 125    extern bool          mb_caseequal (const mbchar_t mbc1, const mbchar_t mbc2);
 126    extern bool          mb_isalnum (const mbchar_t mbc);
 127    extern bool          mb_isalpha (const mbchar_t mbc);
 128    extern bool          mb_isascii (const mbchar_t mbc);
 129    extern bool          mb_isblank (const mbchar_t mbc);
 130    extern bool          mb_iscntrl (const mbchar_t mbc);
 131    extern bool          mb_isdigit (const mbchar_t mbc);
 132    extern bool          mb_isgraph (const mbchar_t mbc);
 133    extern bool          mb_islower (const mbchar_t mbc);
 134    extern bool          mb_isprint (const mbchar_t mbc);
 135    extern bool          mb_ispunct (const mbchar_t mbc);
 136    extern bool          mb_isspace (const mbchar_t mbc);
 137    extern bool          mb_isupper (const mbchar_t mbc);
 138    extern bool          mb_isxdigit (const mbchar_t mbc);
 139    extern int           mb_width (const mbchar_t mbc);
 140    extern void          mb_putc (const mbchar_t mbc, FILE *stream);
 141    extern void          mb_setascii (mbchar_t *new, char sc);
 142    extern void          mb_copy (mbchar_t *new, const mbchar_t *old);
 143  */
 144
 145 #ifndef _MBCHAR_H
 146 #define _MBCHAR_H 1
 147
 148 #include <stdbool.h>
 149 #include <string.h>
 150
 151 /* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
 152    <wchar.h>.
 153    BSD/OS 4.1 has a bug: <stdio.h> and <time.h> must be included before
 154    <wchar.h>.  */
 155 #include <stdio.h>
 156 #include <time.h>
 157 #include <wchar.h>
 158 #include <wctype.h>
 159
 160 #include "wcwidth.h"
 161
 162 #define MBCHAR_BUF_SIZE 24
 163
 164 struct mbchar
 165 {
 166   const char *ptr;      /* pointer to current character */
 167   size_t bytes;         /* number of bytes of current character, > 0 */
 168   bool wc_valid;        /* true if wc is a valid wide character */
 169   wchar_t wc;           /* if wc_valid: the current character */
 170   char buf[MBCHAR_BUF_SIZE]; /* room for the bytes, used for file input only */
 171 };
 172
 173 /* EOF (not a real character) is represented with bytes = 0 and
 174    wc_valid = false.  */
 175
 176 typedef struct mbchar mbchar_t;
 177
 178 /* Access the current character.  */
 179 #define mb_ptr(mbc) ((mbc).ptr)
 180 #define mb_len(mbc) ((mbc).bytes)
 181
 182 /* Comparison of characters.  */
 183 #define mb_iseq(mbc, sc) ((mbc).wc_valid && (mbc).wc == (sc))
 184 #define mb_isnul(mbc) ((mbc).wc_valid && (mbc).wc == 0)
 185 #define mb_cmp(mbc1, mbc2) \
 186   ((mbc1).wc_valid                                                      \
 187    ? ((mbc2).wc_valid                                                   \
 188       ? (int) (mbc1).wc - (int) (mbc2).wc                               \
 189       : -1)                                                             \
 190    : ((mbc2).wc_valid                                                   \
 191       ? 1                                                               \
 192       : (mbc1).bytes == (mbc2).bytes                                    \
 193         ? memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes)                 \
 194         : (mbc1).bytes < (mbc2).bytes                                   \
 195           ? (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) > 0 ? 1 : -1) \
 196           : (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc2).bytes) >= 0 ? 1 : -1)))
 197 #define mb_casecmp(mbc1, mbc2) \
 198   ((mbc1).wc_valid                                                      \
 199    ? ((mbc2).wc_valid                                                   \
 200       ? (int) towlower ((mbc1).wc) - (int) towlower ((mbc2).wc)         \
 201       : -1)                                                             \
 202    : ((mbc2).wc_valid                                                   \
 203       ? 1                                                               \
 204       : (mbc1).bytes == (mbc2).bytes                                    \
 205         ? memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes)                 \
 206         : (mbc1).bytes < (mbc2).bytes                                   \
 207           ? (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) > 0 ? 1 : -1) \
 208           : (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc2).bytes) >= 0 ? 1 : -1)))
 209 #define mb_equal(mbc1, mbc2) \
 210   ((mbc1).wc_valid && (mbc2).wc_valid                                   \
 211    ? (mbc1).wc == (mbc2).wc                                             \
 212    : (mbc1).bytes == (mbc2).bytes                                       \
 213      && memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) == 0)
 214 #define mb_caseequal(mbc1, mbc2) \
 215   ((mbc1).wc_valid && (mbc2).wc_valid                                   \
 216    ? towlower ((mbc1).wc) == towlower ((mbc2).wc)                       \
 217    : (mbc1).bytes == (mbc2).bytes                                       \
 218      && memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) == 0)
 219
 220 /* <ctype.h>, <wctype.h> classification.  */
 221 #define mb_isascii(mbc) \
 222   ((mbc).wc_valid && (mbc).wc >= 0 && (mbc).wc <= 127)
 223 #define mb_isalnum(mbc) ((mbc).wc_valid && iswalnum ((mbc).wc))
 224 #define mb_isalpha(mbc) ((mbc).wc_valid && iswalpha ((mbc).wc))
 225 #define mb_isblank(mbc) ((mbc).wc_valid && iswblank ((mbc).wc))
 226 #define mb_iscntrl(mbc) ((mbc).wc_valid && iswcntrl ((mbc).wc))
 227 #define mb_isdigit(mbc) ((mbc).wc_valid && iswdigit ((mbc).wc))
 228 #define mb_isgraph(mbc) ((mbc).wc_valid && iswgraph ((mbc).wc))
 229 #define mb_islower(mbc) ((mbc).wc_valid && iswlower ((mbc).wc))
 230 #define mb_isprint(mbc) ((mbc).wc_valid && iswprint ((mbc).wc))
 231 #define mb_ispunct(mbc) ((mbc).wc_valid && iswpunct ((mbc).wc))
 232 #define mb_isspace(mbc) ((mbc).wc_valid && iswspace ((mbc).wc))
 233 #define mb_isupper(mbc) ((mbc).wc_valid && iswupper ((mbc).wc))
 234 #define mb_isxdigit(mbc) ((mbc).wc_valid && iswxdigit ((mbc).wc))
 235
 236 /* Extra <wchar.h> function.  */
 237
 238 /* Unprintable characters appear as a small box of width 1.  */
 239 #define MB_UNPRINTABLE_WIDTH 1
 240
 241 static inline int
 242 mb_width_aux (wint_t wc)
 243 {
 244   int w = wcwidth (wc);
 245   /* For unprintable characters, arbitrarily return 0 for control characters
 246      and MB_UNPRINTABLE_WIDTH otherwise.  */
 247   return (w >= 0 ? w : iswcntrl (wc) ? 0 : MB_UNPRINTABLE_WIDTH);
 248 }
 249
 250 #define mb_width(mbc) \
 251   ((mbc).wc_valid ? mb_width_aux ((mbc).wc) : MB_UNPRINTABLE_WIDTH)
 252
 253 /* Output.  */
 254 #define mb_putc(mbc, stream)  fwrite ((mbc).ptr, 1, (mbc).bytes, (stream))
 255
 256 /* Assignment.  */
 257 #define mb_setascii(mbc, sc) \
 258   ((mbc)->ptr = (mbc)->buf, (mbc)->bytes = 1, (mbc)->wc_valid = 1, \
 259    (mbc)->wc = (mbc)->buf[0] = (sc))
 260
 261 /* Copying a character.  */
 262 static inline void
 263 mb_copy (mbchar_t *new_mbc, const mbchar_t *old_mbc)
 264 {
 265   if (old_mbc->ptr == &old_mbc->buf[0])
 266     {
 267       memcpy (&new_mbc->buf[0], &old_mbc->buf[0], old_mbc->bytes);
 268       new_mbc->ptr = &new_mbc->buf[0];
 269     }
 270   else
 271     new_mbc->ptr = old_mbc->ptr;
 272   new_mbc->bytes = old_mbc->bytes;
 273   if ((new_mbc->wc_valid = old_mbc->wc_valid))
 274     new_mbc->wc = old_mbc->wc;
 275 }
 276
 277
 278 /* is_basic(c) tests whether the single-byte character c is in the
 279    ISO C "basic character set".
 280    This is a convenience function, and is in this file only to share code
 281    between mbiter_multi.h and mbfile_multi.h.  */
 282 #if (' ' == 32) && ('!' == 33) && ('"' == 34) && ('#' == 35) \
 283     && ('%' == 37) && ('&' == 38) && ('\'' == 39) && ('(' == 40) \
 284     && (')' == 41) && ('*' == 42) && ('+' == 43) && (',' == 44) \
 285     && ('-' == 45) && ('.' == 46) && ('/' == 47) && ('0' == 48) \
 286     && ('1' == 49) && ('2' == 50) && ('3' == 51) && ('4' == 52) \
 287     && ('5' == 53) && ('6' == 54) && ('7' == 55) && ('8' == 56) \
 288     && ('9' == 57) && (':' == 58) && (';' == 59) && ('<' == 60) \
 289     && ('=' == 61) && ('>' == 62) && ('?' == 63) && ('A' == 65) \
 290     && ('B' == 66) && ('C' == 67) && ('D' == 68) && ('E' == 69) \
 291     && ('F' == 70) && ('G' == 71) && ('H' == 72) && ('I' == 73) \
 292     && ('J' == 74) && ('K' == 75) && ('L' == 76) && ('M' == 77) \
 293     && ('N' == 78) && ('O' == 79) && ('P' == 80) && ('Q' == 81) \
 294     && ('R' == 82) && ('S' == 83) && ('T' == 84) && ('U' == 85) \
 295     && ('V' == 86) && ('W' == 87) && ('X' == 88) && ('Y' == 89) \
 296     && ('Z' == 90) && ('[' == 91) && ('\\' == 92) && (']' == 93) \
 297     && ('^' == 94) && ('_' == 95) && ('a' == 97) && ('b' == 98) \
 298     && ('c' == 99) && ('d' == 100) && ('e' == 101) && ('f' == 102) \
 299     && ('g' == 103) && ('h' == 104) && ('i' == 105) && ('j' == 106) \
 300     && ('k' == 107) && ('l' == 108) && ('m' == 109) && ('n' == 110) \
 301     && ('o' == 111) && ('p' == 112) && ('q' == 113) && ('r' == 114) \
 302     && ('s' == 115) && ('t' == 116) && ('u' == 117) && ('v' == 118) \
 303     && ('w' == 119) && ('x' == 120) && ('y' == 121) && ('z' == 122) \
 304     && ('{' == 123) && ('|' == 124) && ('}' == 125) && ('~' == 126)
 305 /* The character set is ISO-646, not EBCDIC. */
 306 # define IS_BASIC_ASCII 1
 307
 308 extern const unsigned int is_basic_table[];
 309
 310 static inline bool
 311 is_basic (char c)
 312 {
 313   return (is_basic_table [(unsigned char) c >> 5] >> ((unsigned char) c & 31))
 314          & 1;
 315 }
 316
 317 #else
 318
 319 static inline bool
 320 is_basic (char c)
 321 {
 322   switch (c)
 323     {
 324     case '\t': case '\v': case '\f':
 325     case ' ': case '!': case '"': case '#': case '%':
 326     case '&': case '\'': case '(': case ')': case '*':
 327     case '+': case ',': case '-': case '.': case '/':
 328     case '0': case '1': case '2': case '3': case '4':
 329     case '5': case '6': case '7': case '8': case '9':
 330     case ':': case ';': case '<': case '=': case '>':
 331     case '?':
 332     case 'A': case 'B': case 'C': case 'D': case 'E':
 333     case 'F': case 'G': case 'H': case 'I': case 'J':
 334     case 'K': case 'L': case 'M': case 'N': case 'O':
 335     case 'P': case 'Q': case 'R': case 'S': case 'T':
 336     case 'U': case 'V': case 'W': case 'X': case 'Y':
 337     case 'Z':
 338     case '[': case '\\': case ']': case '^': case '_':
 339     case 'a': case 'b': case 'c': case 'd': case 'e':
 340     case 'f': case 'g': case 'h': case 'i': case 'j':
 341     case 'k': case 'l': case 'm': case 'n': case 'o':
 342     case 'p': case 'q': case 'r': case 's': case 't':
 343     case 'u': case 'v': case 'w': case 'x': case 'y':
 344     case 'z': case '{': case '|': case '}': case '~':
 345       return 1;
 346     default:
 347       return 0;
 348     }
 349 }
 350
 351 #endif
 352
 353 #endif /* _MBCHAR_H */