lib/mbchar.h

   1 /* Multibyte character data type.
   2    Copyright (C) 2001, 2005-2007, 2009-2020 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 3 of the License, or
   7    (at your option) 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, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>.  */
  18
  19 /* A multibyte character is a short subsequence of a char* string,
  20    representing a single wide character.
  21
  22    We use multibyte characters instead of wide characters because of
  23    the following goals:
  24    1) correct multibyte handling, i.e. operate according to the LC_CTYPE
  25       locale,
  26    2) ease of maintenance, i.e. the maintainer needs not know all details
  27       of the ISO C 99 standard,
  28    3) don't fail grossly if the input is not in the encoding set by the
  29       locale, because often different encodings are in use in the same
  30       countries (ISO-8859-1/UTF-8, EUC-JP/Shift_JIS, ...),
  31    4) fast in the case of ASCII characters,
  32    5) portability, i.e. don't make unportable assumptions about wchar_t.
  33
  34    Multibyte characters are only accessed through the mb* macros.
  35
  36    mb_ptr (mbc)
  37      return a pointer to the beginning of the multibyte sequence.
  38
  39    mb_len (mbc)
  40      returns the number of bytes occupied by the multibyte sequence.
  41      Always > 0.
  42
  43    mb_iseq (mbc, sc)
  44      returns true if mbc is the standard ASCII character sc.
  45
  46    mb_isnul (mbc)
  47      returns true if mbc is the nul character.
  48
  49    mb_cmp (mbc1, mbc2)
  50      returns a positive, zero, or negative value depending on whether mbc1
  51      sorts after, same or before mbc2.
  52
  53    mb_casecmp (mbc1, mbc2)
  54      returns a positive, zero, or negative value depending on whether mbc1
  55      sorts after, same or before mbc2, modulo upper/lowercase conversion.
  56
  57    mb_equal (mbc1, mbc2)
  58      returns true if mbc1 and mbc2 are equal.
  59
  60    mb_caseequal (mbc1, mbc2)
  61      returns true if mbc1 and mbc2 are equal modulo upper/lowercase conversion.
  62
  63    mb_isalnum (mbc)
  64      returns true if mbc is alphanumeric.
  65
  66    mb_isalpha (mbc)
  67      returns true if mbc is alphabetic.
  68
  69    mb_isascii(mbc)
  70      returns true if mbc is plain ASCII.
  71
  72    mb_isblank (mbc)
  73      returns true if mbc is a blank.
  74
  75    mb_iscntrl (mbc)
  76      returns true if mbc is a control character.
  77
  78    mb_isdigit (mbc)
  79      returns true if mbc is a decimal digit.
  80
  81    mb_isgraph (mbc)
  82      returns true if mbc is a graphic character.
  83
  84    mb_islower (mbc)
  85      returns true if mbc is lowercase.
  86
  87    mb_isprint (mbc)
  88      returns true if mbc is a printable character.
  89
  90    mb_ispunct (mbc)
  91      returns true if mbc is a punctuation character.
  92
  93    mb_isspace (mbc)
  94      returns true if mbc is a space character.
  95
  96    mb_isupper (mbc)
  97      returns true if mbc is uppercase.
  98
  99    mb_isxdigit (mbc)
 100      returns true if mbc is a hexadecimal digit.
 101
 102    mb_width (mbc)
 103      returns the number of columns on the output device occupied by mbc.
 104      Always >= 0.
 105
 106    mb_putc (mbc, stream)
 107      outputs mbc on stream, a byte oriented FILE stream opened for output.
 108
 109    mb_setascii (&mbc, sc)
 110      assigns the standard ASCII character sc to mbc.
 111
 112    mb_copy (&destmbc, &srcmbc)
 113      copies srcmbc to destmbc.
 114
 115    Here are the function prototypes of the macros.
 116
 117    extern const char *  mb_ptr (const mbchar_t mbc);
 118    extern size_t        mb_len (const mbchar_t mbc);
 119    extern bool          mb_iseq (const mbchar_t mbc, char sc);
 120    extern bool          mb_isnul (const mbchar_t mbc);
 121    extern int           mb_cmp (const mbchar_t mbc1, const mbchar_t mbc2);
 122    extern int           mb_casecmp (const mbchar_t mbc1, const mbchar_t mbc2);
 123    extern bool          mb_equal (const mbchar_t mbc1, const mbchar_t mbc2);
 124    extern bool          mb_caseequal (const mbchar_t mbc1, const mbchar_t mbc2);
 125    extern bool          mb_isalnum (const mbchar_t mbc);
 126    extern bool          mb_isalpha (const mbchar_t mbc);
 127    extern bool          mb_isascii (const mbchar_t mbc);
 128    extern bool          mb_isblank (const mbchar_t mbc);
 129    extern bool          mb_iscntrl (const mbchar_t mbc);
 130    extern bool          mb_isdigit (const mbchar_t mbc);
 131    extern bool          mb_isgraph (const mbchar_t mbc);
 132    extern bool          mb_islower (const mbchar_t mbc);
 133    extern bool          mb_isprint (const mbchar_t mbc);
 134    extern bool          mb_ispunct (const mbchar_t mbc);
 135    extern bool          mb_isspace (const mbchar_t mbc);
 136    extern bool          mb_isupper (const mbchar_t mbc);
 137    extern bool          mb_isxdigit (const mbchar_t mbc);
 138    extern int           mb_width (const mbchar_t mbc);
 139    extern void          mb_putc (const mbchar_t mbc, FILE *stream);
 140    extern void          mb_setascii (mbchar_t *new, char sc);
 141    extern void          mb_copy (mbchar_t *new, const mbchar_t *old);
 142  */
 143
 144 #ifndef _MBCHAR_H
 145 #define _MBCHAR_H 1
 146
 147 #include <stdbool.h>
 148 #include <string.h>
 149 #include <wchar.h>
 150 #include <wctype.h>
 151
 152 #ifndef _GL_INLINE_HEADER_BEGIN
 153  #error "Please include config.h first."
 154 #endif
 155 _GL_INLINE_HEADER_BEGIN
 156 #ifndef MBCHAR_INLINE
 157 # define MBCHAR_INLINE _GL_INLINE
 158 #endif
 159
 160 #define MBCHAR_BUF_SIZE 24
 161
 162 struct mbchar
 163 {
 164   const char *ptr;      /* pointer to current character */
 165   size_t bytes;         /* number of bytes of current character, > 0 */
 166   bool wc_valid;        /* true if wc is a valid wide character */
 167   wchar_t wc;           /* if wc_valid: the current character */
 168   char buf[MBCHAR_BUF_SIZE]; /* room for the bytes, used for file input only */
 169 };
 170
 171 /* EOF (not a real character) is represented with bytes = 0 and
 172    wc_valid = false.  */
 173
 174 typedef struct mbchar mbchar_t;
 175
 176 /* Access the current character.  */
 177 #define mb_ptr(mbc) ((mbc).ptr)
 178 #define mb_len(mbc) ((mbc).bytes)
 179
 180 /* Comparison of characters.  */
 181 #define mb_iseq(mbc, sc) ((mbc).wc_valid && (mbc).wc == (sc))
 182 #define mb_isnul(mbc) ((mbc).wc_valid && (mbc).wc == 0)
 183 #define mb_cmp(mbc1, mbc2) \
 184   ((mbc1).wc_valid                                                      \
 185    ? ((mbc2).wc_valid                                                   \
 186       ? (int) (mbc1).wc - (int) (mbc2).wc                               \
 187       : -1)                                                             \
 188    : ((mbc2).wc_valid                                                   \
 189       ? 1                                                               \
 190       : (mbc1).bytes == (mbc2).bytes                                    \
 191         ? memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes)                 \
 192         : (mbc1).bytes < (mbc2).bytes                                   \
 193           ? (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) > 0 ? 1 : -1) \
 194           : (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc2).bytes) >= 0 ? 1 : -1)))
 195 #define mb_casecmp(mbc1, mbc2) \
 196   ((mbc1).wc_valid                                                      \
 197    ? ((mbc2).wc_valid                                                   \
 198       ? (int) towlower ((mbc1).wc) - (int) towlower ((mbc2).wc)         \
 199       : -1)                                                             \
 200    : ((mbc2).wc_valid                                                   \
 201       ? 1                                                               \
 202       : (mbc1).bytes == (mbc2).bytes                                    \
 203         ? memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes)                 \
 204         : (mbc1).bytes < (mbc2).bytes                                   \
 205           ? (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) > 0 ? 1 : -1) \
 206           : (memcmp ((mbc1).ptr, (mbc2).ptr, (mbc2).bytes) >= 0 ? 1 : -1)))
 207 #define mb_equal(mbc1, mbc2) \
 208   ((mbc1).wc_valid && (mbc2).wc_valid                                   \
 209    ? (mbc1).wc == (mbc2).wc                                             \
 210    : (mbc1).bytes == (mbc2).bytes                                       \
 211      && memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) == 0)
 212 #define mb_caseequal(mbc1, mbc2) \
 213   ((mbc1).wc_valid && (mbc2).wc_valid                                   \
 214    ? towlower ((mbc1).wc) == towlower ((mbc2).wc)                       \
 215    : (mbc1).bytes == (mbc2).bytes                                       \
 216      && memcmp ((mbc1).ptr, (mbc2).ptr, (mbc1).bytes) == 0)
 217
 218 /* <ctype.h>, <wctype.h> classification.  */
 219 #define mb_isascii(mbc) \
 220   ((mbc).wc_valid && (mbc).wc >= 0 && (mbc).wc <= 127)
 221 #define mb_isalnum(mbc) ((mbc).wc_valid && iswalnum ((mbc).wc))
 222 #define mb_isalpha(mbc) ((mbc).wc_valid && iswalpha ((mbc).wc))
 223 #define mb_isblank(mbc) ((mbc).wc_valid && iswblank ((mbc).wc))
 224 #define mb_iscntrl(mbc) ((mbc).wc_valid && iswcntrl ((mbc).wc))
 225 #define mb_isdigit(mbc) ((mbc).wc_valid && iswdigit ((mbc).wc))
 226 #define mb_isgraph(mbc) ((mbc).wc_valid && iswgraph ((mbc).wc))
 227 #define mb_islower(mbc) ((mbc).wc_valid && iswlower ((mbc).wc))
 228 #define mb_isprint(mbc) ((mbc).wc_valid && iswprint ((mbc).wc))
 229 #define mb_ispunct(mbc) ((mbc).wc_valid && iswpunct ((mbc).wc))
 230 #define mb_isspace(mbc) ((mbc).wc_valid && iswspace ((mbc).wc))
 231 #define mb_isupper(mbc) ((mbc).wc_valid && iswupper ((mbc).wc))
 232 #define mb_isxdigit(mbc) ((mbc).wc_valid && iswxdigit ((mbc).wc))
 233
 234 /* Extra <wchar.h> function.  */
 235
 236 /* Unprintable characters appear as a small box of width 1.  */
 237 #define MB_UNPRINTABLE_WIDTH 1
 238
 239 MBCHAR_INLINE int
 240 mb_width_aux (wint_t wc)
 241 {
 242   int w = wcwidth (wc);
 243   /* For unprintable characters, arbitrarily return 0 for control characters
 244      and MB_UNPRINTABLE_WIDTH otherwise.  */
 245   return (w >= 0 ? w : iswcntrl (wc) ? 0 : MB_UNPRINTABLE_WIDTH);
 246 }
 247
 248 #define mb_width(mbc) \
 249   ((mbc).wc_valid ? mb_width_aux ((mbc).wc) : MB_UNPRINTABLE_WIDTH)
 250
 251 /* Output.  */
 252 #define mb_putc(mbc, stream)  fwrite ((mbc).ptr, 1, (mbc).bytes, (stream))
 253
 254 /* Assignment.  */
 255 #define mb_setascii(mbc, sc) \
 256   ((mbc)->ptr = (mbc)->buf, (mbc)->bytes = 1, (mbc)->wc_valid = 1, \
 257    (mbc)->wc = (mbc)->buf[0] = (sc))
 258
 259 /* Copying a character.  */
 260 MBCHAR_INLINE void
 261 mb_copy (mbchar_t *new_mbc, const mbchar_t *old_mbc)
 262 {
 263   if (old_mbc->ptr == &old_mbc->buf[0])
 264     {
 265       memcpy (&new_mbc->buf[0], &old_mbc->buf[0], old_mbc->bytes);
 266       new_mbc->ptr = &new_mbc->buf[0];
 267     }
 268   else
 269     new_mbc->ptr = old_mbc->ptr;
 270   new_mbc->bytes = old_mbc->bytes;
 271   if ((new_mbc->wc_valid = old_mbc->wc_valid))
 272     new_mbc->wc = old_mbc->wc;
 273 }
 274
 275
 276 /* is_basic(c) tests whether the single-byte character c is in the
 277    ISO C "basic character set".
 278    This is a convenience function, and is in this file only to share code
 279    between mbiter_multi.h and mbfile_multi.h.  */
 280 #if (' ' == 32) && ('!' == 33) && ('"' == 34) && ('#' == 35) \
 281     && ('%' == 37) && ('&' == 38) && ('\'' == 39) && ('(' == 40) \
 282     && (')' == 41) && ('*' == 42) && ('+' == 43) && (',' == 44) \
 283     && ('-' == 45) && ('.' == 46) && ('/' == 47) && ('0' == 48) \
 284     && ('1' == 49) && ('2' == 50) && ('3' == 51) && ('4' == 52) \
 285     && ('5' == 53) && ('6' == 54) && ('7' == 55) && ('8' == 56) \
 286     && ('9' == 57) && (':' == 58) && (';' == 59) && ('<' == 60) \
 287     && ('=' == 61) && ('>' == 62) && ('?' == 63) && ('A' == 65) \
 288     && ('B' == 66) && ('C' == 67) && ('D' == 68) && ('E' == 69) \
 289     && ('F' == 70) && ('G' == 71) && ('H' == 72) && ('I' == 73) \
 290     && ('J' == 74) && ('K' == 75) && ('L' == 76) && ('M' == 77) \
 291     && ('N' == 78) && ('O' == 79) && ('P' == 80) && ('Q' == 81) \
 292     && ('R' == 82) && ('S' == 83) && ('T' == 84) && ('U' == 85) \
 293     && ('V' == 86) && ('W' == 87) && ('X' == 88) && ('Y' == 89) \
 294     && ('Z' == 90) && ('[' == 91) && ('\\' == 92) && (']' == 93) \
 295     && ('^' == 94) && ('_' == 95) && ('a' == 97) && ('b' == 98) \
 296     && ('c' == 99) && ('d' == 100) && ('e' == 101) && ('f' == 102) \
 297     && ('g' == 103) && ('h' == 104) && ('i' == 105) && ('j' == 106) \
 298     && ('k' == 107) && ('l' == 108) && ('m' == 109) && ('n' == 110) \
 299     && ('o' == 111) && ('p' == 112) && ('q' == 113) && ('r' == 114) \
 300     && ('s' == 115) && ('t' == 116) && ('u' == 117) && ('v' == 118) \
 301     && ('w' == 119) && ('x' == 120) && ('y' == 121) && ('z' == 122) \
 302     && ('{' == 123) && ('|' == 124) && ('}' == 125) && ('~' == 126)
 303 /* The character set is ISO-646, not EBCDIC. */
 304 # define IS_BASIC_ASCII 1
 305
 306 extern const unsigned int is_basic_table[];
 307
 308 MBCHAR_INLINE bool
 309 is_basic (char c)
 310 {
 311   return (is_basic_table [(unsigned char) c >> 5] >> ((unsigned char) c & 31))
 312          & 1;
 313 }
 314
 315 #else
 316
 317 MBCHAR_INLINE bool
 318 is_basic (char c)
 319 {
 320   switch (c)
 321     {
 322     case '\t': case '\v': case '\f':
 323     case ' ': case '!': case '"': case '#': case '%':
 324     case '&': case '\'': case '(': case ')': case '*':
 325     case '+': case ',': case '-': case '.': case '/':
 326     case '0': case '1': case '2': case '3': case '4':
 327     case '5': case '6': case '7': case '8': case '9':
 328     case ':': case ';': case '<': case '=': case '>':
 329     case '?':
 330     case 'A': case 'B': case 'C': case 'D': case 'E':
 331     case 'F': case 'G': case 'H': case 'I': case 'J':
 332     case 'K': case 'L': case 'M': case 'N': case 'O':
 333     case 'P': case 'Q': case 'R': case 'S': case 'T':
 334     case 'U': case 'V': case 'W': case 'X': case 'Y':
 335     case 'Z':
 336     case '[': case '\\': case ']': case '^': case '_':
 337     case 'a': case 'b': case 'c': case 'd': case 'e':
 338     case 'f': case 'g': case 'h': case 'i': case 'j':
 339     case 'k': case 'l': case 'm': case 'n': case 'o':
 340     case 'p': case 'q': case 'r': case 's': case 't':
 341     case 'u': case 'v': case 'w': case 'x': case 'y':
 342     case 'z': case '{': case '|': case '}': case '~':
 343       return 1;
 344     default:
 345       return 0;
 346     }
 347 }
 348
 349 #endif
 350
 351 _GL_INLINE_HEADER_END
 352
 353 #endif /* _MBCHAR_H */