lib/c-ctype.h

   1 /* Character handling in C locale.
   2
   3    These functions work like the corresponding functions in <ctype.h>,
   4    except that they have the C (POSIX) locale hardwired, whereas the
   5    <ctype.h> functions' behaviour depends on the current locale set via
   6    setlocale.
   7
   8    Copyright (C) 2000-2003, 2006, 2008-2019 Free Software Foundation, Inc.
   9
  10 This program is free software; you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation; either version 2 of the License, or
  13 (at your option) any later version.
  14
  15 This program is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with this program; if not, see <https://www.gnu.org/licenses/>.  */
  22
  23 #ifndef C_CTYPE_H
  24 #define C_CTYPE_H
  25
  26 #include <stdbool.h>
  27
  28 #ifndef _GL_INLINE_HEADER_BEGIN
  29  #error "Please include config.h first."
  30 #endif
  31 _GL_INLINE_HEADER_BEGIN
  32 #ifndef C_CTYPE_INLINE
  33 # define C_CTYPE_INLINE _GL_INLINE
  34 #endif
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40
  41 /* The functions defined in this file assume the "C" locale and a character
  42    set without diacritics (ASCII-US or EBCDIC-US or something like that).
  43    Even if the "C" locale on a particular system is an extension of the ASCII
  44    character set (like on BeOS, where it is UTF-8, or on AmigaOS, where it
  45    is ISO-8859-1), the functions in this file recognize only the ASCII
  46    characters.  */
  47
  48
  49 #if (' ' == 32) && ('!' == 33) && ('"' == 34) && ('#' == 35) \
  50     && ('%' == 37) && ('&' == 38) && ('\'' == 39) && ('(' == 40) \
  51     && (')' == 41) && ('*' == 42) && ('+' == 43) && (',' == 44) \
  52     && ('-' == 45) && ('.' == 46) && ('/' == 47) && ('0' == 48) \
  53     && ('1' == 49) && ('2' == 50) && ('3' == 51) && ('4' == 52) \
  54     && ('5' == 53) && ('6' == 54) && ('7' == 55) && ('8' == 56) \
  55     && ('9' == 57) && (':' == 58) && (';' == 59) && ('<' == 60) \
  56     && ('=' == 61) && ('>' == 62) && ('?' == 63) && ('A' == 65) \
  57     && ('B' == 66) && ('C' == 67) && ('D' == 68) && ('E' == 69) \
  58     && ('F' == 70) && ('G' == 71) && ('H' == 72) && ('I' == 73) \
  59     && ('J' == 74) && ('K' == 75) && ('L' == 76) && ('M' == 77) \
  60     && ('N' == 78) && ('O' == 79) && ('P' == 80) && ('Q' == 81) \
  61     && ('R' == 82) && ('S' == 83) && ('T' == 84) && ('U' == 85) \
  62     && ('V' == 86) && ('W' == 87) && ('X' == 88) && ('Y' == 89) \
  63     && ('Z' == 90) && ('[' == 91) && ('\\' == 92) && (']' == 93) \
  64     && ('^' == 94) && ('_' == 95) && ('a' == 97) && ('b' == 98) \
  65     && ('c' == 99) && ('d' == 100) && ('e' == 101) && ('f' == 102) \
  66     && ('g' == 103) && ('h' == 104) && ('i' == 105) && ('j' == 106) \
  67     && ('k' == 107) && ('l' == 108) && ('m' == 109) && ('n' == 110) \
  68     && ('o' == 111) && ('p' == 112) && ('q' == 113) && ('r' == 114) \
  69     && ('s' == 115) && ('t' == 116) && ('u' == 117) && ('v' == 118) \
  70     && ('w' == 119) && ('x' == 120) && ('y' == 121) && ('z' == 122) \
  71     && ('{' == 123) && ('|' == 124) && ('}' == 125) && ('~' == 126)
  72 /* The character set is ASCII or one of its variants or extensions, not EBCDIC.
  73    Testing the value of '\n' and '\r' is not relevant.  */
  74 # define C_CTYPE_ASCII 1
  75 #elif ! (' ' == '\x40' && '0' == '\xf0'                     \
  76          && 'A' == '\xc1' && 'J' == '\xd1' && 'S' == '\xe2' \
  77          && 'a' == '\x81' && 'j' == '\x91' && 's' == '\xa2')
  78 # error "Only ASCII and EBCDIC are supported"
  79 #endif
  80
  81 #if 'A' < 0
  82 # error "EBCDIC and char is signed -- not supported"
  83 #endif
  84
  85 /* Cases for control characters.  */
  86
  87 #define _C_CTYPE_CNTRL \
  88    case '\a': case '\b': case '\f': case '\n': \
  89    case '\r': case '\t': case '\v': \
  90    _C_CTYPE_OTHER_CNTRL
  91
  92 /* ASCII control characters other than those with \-letter escapes.  */
  93
  94 #if C_CTYPE_ASCII
  95 # define _C_CTYPE_OTHER_CNTRL \
  96     case '\x00': case '\x01': case '\x02': case '\x03': \
  97     case '\x04': case '\x05': case '\x06': case '\x0e': \
  98     case '\x0f': case '\x10': case '\x11': case '\x12': \
  99     case '\x13': case '\x14': case '\x15': case '\x16': \
 100     case '\x17': case '\x18': case '\x19': case '\x1a': \
 101     case '\x1b': case '\x1c': case '\x1d': case '\x1e': \
 102     case '\x1f': case '\x7f'
 103 #else
 104    /* Use EBCDIC code page 1047's assignments for ASCII control chars;
 105       assume all EBCDIC code pages agree about these assignments.  */
 106 # define _C_CTYPE_OTHER_CNTRL \
 107     case '\x00': case '\x01': case '\x02': case '\x03': \
 108     case '\x07': case '\x0e': case '\x0f': case '\x10': \
 109     case '\x11': case '\x12': case '\x13': case '\x18': \
 110     case '\x19': case '\x1c': case '\x1d': case '\x1e': \
 111     case '\x1f': case '\x26': case '\x27': case '\x2d': \
 112     case '\x2e': case '\x32': case '\x37': case '\x3c': \
 113     case '\x3d': case '\x3f'
 114 #endif
 115
 116 /* Cases for lowercase hex letters, and lowercase letters, all offset by N.  */
 117
 118 #define _C_CTYPE_LOWER_A_THRU_F_N(N) \
 119    case 'a' + (N): case 'b' + (N): case 'c' + (N): case 'd' + (N): \
 120    case 'e' + (N): case 'f' + (N)
 121 #define _C_CTYPE_LOWER_N(N) \
 122    _C_CTYPE_LOWER_A_THRU_F_N(N): \
 123    case 'g' + (N): case 'h' + (N): case 'i' + (N): case 'j' + (N): \
 124    case 'k' + (N): case 'l' + (N): case 'm' + (N): case 'n' + (N): \
 125    case 'o' + (N): case 'p' + (N): case 'q' + (N): case 'r' + (N): \
 126    case 's' + (N): case 't' + (N): case 'u' + (N): case 'v' + (N): \
 127    case 'w' + (N): case 'x' + (N): case 'y' + (N): case 'z' + (N)
 128
 129 /* Cases for hex letters, digits, lower, punct, and upper.  */
 130
 131 #define _C_CTYPE_A_THRU_F \
 132    _C_CTYPE_LOWER_A_THRU_F_N (0): \
 133    _C_CTYPE_LOWER_A_THRU_F_N ('A' - 'a')
 134 #define _C_CTYPE_DIGIT                     \
 135    case '0': case '1': case '2': case '3': \
 136    case '4': case '5': case '6': case '7': \
 137    case '8': case '9'
 138 #define _C_CTYPE_LOWER _C_CTYPE_LOWER_N (0)
 139 #define _C_CTYPE_PUNCT \
 140    case '!': case '"': case '#': case '$':  \
 141    case '%': case '&': case '\'': case '(': \
 142    case ')': case '*': case '+': case ',':  \
 143    case '-': case '.': case '/': case ':':  \
 144    case ';': case '<': case '=': case '>':  \
 145    case '?': case '@': case '[': case '\\': \
 146    case ']': case '^': case '_': case '`':  \
 147    case '{': case '|': case '}': case '~'
 148 #define _C_CTYPE_UPPER _C_CTYPE_LOWER_N ('A' - 'a')
 149
 150
 151 /* Function definitions.  */
 152
 153 /* Unlike the functions in <ctype.h>, which require an argument in the range
 154    of the 'unsigned char' type, the functions here operate on values that are
 155    in the 'unsigned char' range or in the 'char' range.  In other words,
 156    when you have a 'char' value, you need to cast it before using it as
 157    argument to a <ctype.h> function:
 158
 159          const char *s = ...;
 160          if (isalpha ((unsigned char) *s)) ...
 161
 162    but you don't need to cast it for the functions defined in this file:
 163
 164          const char *s = ...;
 165          if (c_isalpha (*s)) ...
 166  */
 167
 168 C_CTYPE_INLINE bool
 169 c_isalnum (int c)
 170 {
 171   switch (c)
 172     {
 173     _C_CTYPE_DIGIT:
 174     _C_CTYPE_LOWER:
 175     _C_CTYPE_UPPER:
 176       return true;
 177     default:
 178       return false;
 179     }
 180 }
 181
 182 C_CTYPE_INLINE bool
 183 c_isalpha (int c)
 184 {
 185   switch (c)
 186     {
 187     _C_CTYPE_LOWER:
 188     _C_CTYPE_UPPER:
 189       return true;
 190     default:
 191       return false;
 192     }
 193 }
 194
 195 /* The function isascii is not locale dependent.
 196    Its use in EBCDIC is questionable. */
 197 C_CTYPE_INLINE bool
 198 c_isascii (int c)
 199 {
 200   switch (c)
 201     {
 202     case ' ':
 203     _C_CTYPE_CNTRL:
 204     _C_CTYPE_DIGIT:
 205     _C_CTYPE_LOWER:
 206     _C_CTYPE_PUNCT:
 207     _C_CTYPE_UPPER:
 208       return true;
 209     default:
 210       return false;
 211     }
 212 }
 213
 214 C_CTYPE_INLINE bool
 215 c_isblank (int c)
 216 {
 217   return c == ' ' || c == '\t';
 218 }
 219
 220 C_CTYPE_INLINE bool
 221 c_iscntrl (int c)
 222 {
 223   switch (c)
 224     {
 225     _C_CTYPE_CNTRL:
 226       return true;
 227     default:
 228       return false;
 229     }
 230 }
 231
 232 C_CTYPE_INLINE bool
 233 c_isdigit (int c)
 234 {
 235   switch (c)
 236     {
 237     _C_CTYPE_DIGIT:
 238       return true;
 239     default:
 240       return false;
 241     }
 242 }
 243
 244 C_CTYPE_INLINE bool
 245 c_isgraph (int c)
 246 {
 247   switch (c)
 248     {
 249     _C_CTYPE_DIGIT:
 250     _C_CTYPE_LOWER:
 251     _C_CTYPE_PUNCT:
 252     _C_CTYPE_UPPER:
 253       return true;
 254     default:
 255       return false;
 256     }
 257 }
 258
 259 C_CTYPE_INLINE bool
 260 c_islower (int c)
 261 {
 262   switch (c)
 263     {
 264     _C_CTYPE_LOWER:
 265       return true;
 266     default:
 267       return false;
 268     }
 269 }
 270
 271 C_CTYPE_INLINE bool
 272 c_isprint (int c)
 273 {
 274   switch (c)
 275     {
 276     case ' ':
 277     _C_CTYPE_DIGIT:
 278     _C_CTYPE_LOWER:
 279     _C_CTYPE_PUNCT:
 280     _C_CTYPE_UPPER:
 281       return true;
 282     default:
 283       return false;
 284     }
 285 }
 286
 287 C_CTYPE_INLINE bool
 288 c_ispunct (int c)
 289 {
 290   switch (c)
 291     {
 292     _C_CTYPE_PUNCT:
 293       return true;
 294     default:
 295       return false;
 296     }
 297 }
 298
 299 C_CTYPE_INLINE bool
 300 c_isspace (int c)
 301 {
 302   switch (c)
 303     {
 304     case ' ': case '\t': case '\n': case '\v': case '\f': case '\r':
 305       return true;
 306     default:
 307       return false;
 308     }
 309 }
 310
 311 C_CTYPE_INLINE bool
 312 c_isupper (int c)
 313 {
 314   switch (c)
 315     {
 316     _C_CTYPE_UPPER:
 317       return true;
 318     default:
 319       return false;
 320     }
 321 }
 322
 323 C_CTYPE_INLINE bool
 324 c_isxdigit (int c)
 325 {
 326   switch (c)
 327     {
 328     _C_CTYPE_DIGIT:
 329     _C_CTYPE_A_THRU_F:
 330       return true;
 331     default:
 332       return false;
 333     }
 334 }
 335
 336 C_CTYPE_INLINE int
 337 c_tolower (int c)
 338 {
 339   switch (c)
 340     {
 341     _C_CTYPE_UPPER:
 342       return c - 'A' + 'a';
 343     default:
 344       return c;
 345     }
 346 }
 347
 348 C_CTYPE_INLINE int
 349 c_toupper (int c)
 350 {
 351   switch (c)
 352     {
 353     _C_CTYPE_LOWER:
 354       return c - 'a' + 'A';
 355     default:
 356       return c;
 357     }
 358 }
 359
 360 #ifdef __cplusplus
 361 }
 362 #endif
 363
 364 _GL_INLINE_HEADER_END
 365
 366 #endif /* C_CTYPE_H */