diplodocus.org Git - nmh/blob - test/getcwidth.c

   1 /*
   2  * getcwidth - Get the OS's idea of the width of a combining character
   3  *
   4  * This code is Copyright (c) 2012, by the authors of nmh.  See the
   5  * COPYRIGHT file in the root directory of the nmh distribution for
   6  * complete copyright information.
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <errno.h>
  13
  14 #ifdef HAVE_CONFIG_H
  15 #include <config.h>
  16 #endif
  17
  18 #ifdef MULTIBYTE_SUPPORT
  19 #include <locale.h>
  20 #include <wchar.h>
  21 #endif
  22
  23 static void usage(char *);
  24 static void dumpwidth(void);
  25
  26 int
  27 main(int argc, char *argv[])
  28 {
  29         wchar_t c;
  30         int charlen;
  31         char *p;
  32
  33         /*
  34          * This is the UTF-8 for "n" + U+0308 (Combining Diaeresis)
  35          */
  36
  37         unsigned char string[] = "n\xcc\x88";
  38
  39         setlocale(LC_ALL, "");
  40
  41         if (argc > 2)
  42                 usage(argv[0]);
  43
  44         if (argc == 2) {
  45                 if (strcmp(argv[1], "--dump") == 0) {
  46                         dumpwidth();
  47                         exit(0);
  48                 } else {
  49                         usage(argv[0]);
  50                 }
  51         }
  52
  53 #ifndef MULTIBYTE_SUPPORT
  54         fprintf(stderr, "Nmh was not configured with multibyte support\n");
  55         exit(1);
  56 #else /* MULTIBYTE_SUPPORT */
  57         /*
  58          * It's not clear to me that we can just call mbtowc() with a
  59          * combining character; just to be safe, feed it in a base
  60          * character first.
  61          */
  62
  63         mbtowc(NULL, NULL, 0);
  64
  65         charlen = mbtowc(&c, (char *) string, strlen((char *) string));
  66
  67         if (charlen != 1) {
  68                 fprintf(stderr, "We expected a beginning character length "
  69                         "of 1, got %d instead\n", charlen);
  70                 exit(1);
  71         }
  72
  73         p = (char *) (string + charlen);
  74
  75         charlen = mbtowc(&c, p, strlen(p));
  76
  77         if (charlen != 2) {
  78                 fprintf(stderr, "We expected a multibyte character length "
  79                         "of 2, got %d instead\n", charlen);
  80                 fprintf(stderr, "Are you using a UTF-8 locale?\n");
  81                 exit(1);
  82         }
  83
  84         printf("%d\n", wcwidth(c));
  85
  86         exit(0);
  87 #endif /* MULTIBYTE_SUPPORT */
  88 }
  89
  90 static void
  91 usage(char *argv0)
  92 {
  93         fprintf(stderr, "Usage: %s [--dump]\n", argv0);
  94         fprintf(stderr, "Returns the column width of a UTF-8 combining "
  95                 "multibyte character\n");
  96         fprintf(stderr, "\t--dump\tDump complete width table\n");
  97
  98         exit(1);
  99 }
 100
 101 static void
 102 dumpwidth(void)
 103 {
 104 #ifndef MULTIBYTE_SUPPORT
 105         fprintf(stderr, "Nmh was not configured with multibyte support\n");
 106         exit(1);
 107 #else /* MULTIBYTE_SUPPORT */
 108         wchar_t wc, low;
 109         int width, lastwidth;
 110
 111         for (wc = low = 1, lastwidth = wcwidth(wc); wc <= 0xffff; wc++) {
 112                 width = wcwidth(wc);
 113                 if (width != lastwidth) {
 114                         printf("%04X - %04X = %d\n", low, wc - 1, lastwidth);
 115                         low = wc;
 116                 }
 117                 lastwidth = width;
 118         }
 119
 120         width = wcwidth(wc - 1);
 121         if (width == lastwidth)
 122                 printf("%04X - %04X = %d\n", low, wc - 1, width);
 123 #endif /* MULTIBYTE_SUPPORT */
 124 }