1/* -*- c-file-style: "gnu" -*- */ 2/* 3 * This is a quick-and-dirty emulator of the nl_langinfo(CODESET) 4 * function defined in the Single Unix Specification for those systems 5 * (FreeBSD, etc.) that don't have one yet. It behaves as if it had 6 * been called after setlocale(LC_CTYPE, ""), that is it looks at 7 * the locale environment variables. 8 * 9 * http://www.opengroup.org/onlinepubs/7908799/xsh/langinfo.h.html 10 * 11 * Please extend it as needed and suggest improvements to the author. 12 * This emulator will hopefully become redundant soon as 13 * nl_langinfo(CODESET) becomes more widely implemented. 14 * 15 * Since the proposed Li18nux encoding name registry is still not mature, 16 * the output follows the MIME registry where possible: 17 * 18 * http://www.iana.org/assignments/character-sets 19 * 20 * A possible autoconf test for the availability of nl_langinfo(CODESET) 21 * can be found in 22 * 23 * http://www.cl.cam.ac.uk/~mgk25/unicode.html#activate 24 * 25 * Markus.Kuhn@cl.cam.ac.uk -- 2002-03-11 26 * Permission to use, copy, modify, and distribute this software 27 * for any purpose and without fee is hereby granted. The author 28 * disclaims all warranties with regard to this software. 29 * 30 * Latest version: 31 * 32 * http://www.cl.cam.ac.uk/~mgk25/ucs/langinfo.c 33 */ 34 35#include "ruby/missing.h" 36#include <stdlib.h> 37#include <string.h> 38#if defined _WIN32 || defined __CYGWIN__ 39#include <windows.h> 40#if defined _WIN32 && !defined strncasecmp 41#define strncasecmp strnicmp 42#endif 43#endif 44#ifdef HAVE_LANGINFO_H 45#include "langinfo.h" 46#endif 47 48#define C_CODESET "US-ASCII" /* Return this as the encoding of the 49 * C/POSIX locale. Could as well one day 50 * become "UTF-8". */ 51 52#if defined _WIN32 || defined __CYGWIN__ 53#define JA_CODESET "Windows-31J" 54#else 55#define JA_CODESET "EUC-JP" 56#endif 57 58#define digit(x) ((x) >= '0' && (x) <= '9') 59#define strstart(s, n) (strncasecmp((s), (n), strlen(n)) == 0) 60 61static char buf[16]; 62 63const char * 64nl_langinfo_codeset(void) 65{ 66 const char *l, *p; 67 int n; 68 69 if (((l = getenv("LC_ALL")) && *l) || 70 ((l = getenv("LC_CTYPE")) && *l) || 71 ((l = getenv("LANG")) && *l)) { 72 /* check standardized locales */ 73 if (!strcmp(l, "C") || !strcmp(l, "POSIX")) 74 return C_CODESET; 75 /* check for encoding name fragment */ 76 p = strchr(l, '.'); 77 if (!p++) p = l; 78 if (strstart(p, "UTF")) 79 return "UTF-8"; 80 if ((n = 5, strstart(p, "8859-")) || (n = 9, strstart(p, "ISO-8859-"))) { 81 if (digit(p[n])) { 82 p += n; 83 memcpy(buf, "ISO-8859-\0\0", 12); 84 buf[9] = *p++; 85 if (digit(*p)) buf[10] = *p++; 86 return buf; 87 } 88 } 89 if (strstart(p, "KOI8-R")) return "KOI8-R"; 90 if (strstart(p, "KOI8-U")) return "KOI8-U"; 91 if (strstart(p, "620")) return "TIS-620"; 92 if (strstart(p, "2312")) return "GB2312"; 93 if (strstart(p, "HKSCS")) return "Big5HKSCS"; /* no MIME charset */ 94 if (strstart(p, "BIG5")) return "Big5"; 95 if (strstart(p, "GBK")) return "GBK"; /* no MIME charset */ 96 if (strstart(p, "18030")) return "GB18030"; /* no MIME charset */ 97 if (strstart(p, "Shift_JIS") || strstart(p, "SJIS")) return "Windows-31J"; 98 /* check for conclusive modifier */ 99 if (strstart(p, "euro")) return "ISO-8859-15"; 100 /* check for language (and perhaps country) codes */ 101 if (strstart(l, "zh_TW")) return "Big5"; 102 if (strstart(l, "zh_HK")) return "Big5HKSCS"; /* no MIME charset */ 103 if (strstart(l, "zh")) return "GB2312"; 104 if (strstart(l, "ja")) return JA_CODESET; 105 if (strstart(l, "ko")) return "EUC-KR"; 106 if (strstart(l, "ru")) return "KOI8-R"; 107 if (strstart(l, "uk")) return "KOI8-U"; 108 if (strstart(l, "pl") || strstart(l, "hr") || 109 strstart(l, "hu") || strstart(l, "cs") || 110 strstart(l, "sk") || strstart(l, "sl")) return "ISO-8859-2"; 111 if (strstart(l, "eo") || strstart(l, "mt")) return "ISO-8859-3"; 112 if (strstart(l, "el")) return "ISO-8859-7"; 113 if (strstart(l, "he")) return "ISO-8859-8"; 114 if (strstart(l, "tr")) return "ISO-8859-9"; 115 if (strstart(l, "th")) return "TIS-620"; /* or ISO-8859-11 */ 116 if (strstart(l, "lt")) return "ISO-8859-13"; 117 if (strstart(l, "cy")) return "ISO-8859-14"; 118 if (strstart(l, "ro")) return "ISO-8859-2"; /* or ISO-8859-16 */ 119 if (strstart(l, "am") || strstart(l, "vi")) return "UTF-8"; 120 /* Send me further rules if you like, but don't forget that we are 121 * *only* interested in locale naming conventions on platforms 122 * that do not already provide an nl_langinfo(CODESET) implementation. */ 123 } 124 return NULL; 125} 126 127#ifdef HAVE_LANGINFO_H 128char *nl_langinfo(nl_item item) 129{ 130 const char *codeset; 131 if (item != CODESET) 132 return NULL; 133 codeset = nl_langinfo_codeset(); 134 if (!codeset) codeset = C_CODESET; 135 return (char *)codeset; 136} 137#endif 138 139/* For a demo, compile with "gcc -W -Wall -o langinfo -D TEST langinfo.c" */ 140 141#ifdef TEST 142#include <stdio.h> 143int main() 144{ 145 printf("%s\n", nl_langinfo(CODESET)); 146 return 0; 147} 148#endif 149