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chklocale.c
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1 /*-------------------------------------------------------------------------
2  *
3  * chklocale.c
4  * Functions for handling locale-related info
5  *
6  *
7  * Copyright (c) 1996-2020, PostgreSQL Global Development Group
8  *
9  *
10  * IDENTIFICATION
11  * src/port/chklocale.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 
16 #ifndef FRONTEND
17 #include "postgres.h"
18 #else
19 #include "postgres_fe.h"
20 #endif
21 
22 #ifdef HAVE_LANGINFO_H
23 #include <langinfo.h>
24 #endif
25 
26 #include "mb/pg_wchar.h"
27 
28 
29 /*
30  * This table needs to recognize all the CODESET spellings for supported
31  * backend encodings, as well as frontend-only encodings where possible
32  * (the latter case is currently only needed for initdb to recognize
33  * error situations). On Windows, we rely on entries for codepage
34  * numbers (CPnnn).
35  *
36  * Note that we search the table with pg_strcasecmp(), so variant
37  * capitalizations don't need their own entries.
38  */
40 {
42  const char *system_enc_name;
43 };
44 
45 static const struct encoding_match encoding_match_list[] = {
46  {PG_EUC_JP, "EUC-JP"},
47  {PG_EUC_JP, "eucJP"},
48  {PG_EUC_JP, "IBM-eucJP"},
49  {PG_EUC_JP, "sdeckanji"},
50  {PG_EUC_JP, "CP20932"},
51 
52  {PG_EUC_CN, "EUC-CN"},
53  {PG_EUC_CN, "eucCN"},
54  {PG_EUC_CN, "IBM-eucCN"},
55  {PG_EUC_CN, "GB2312"},
56  {PG_EUC_CN, "dechanzi"},
57  {PG_EUC_CN, "CP20936"},
58 
59  {PG_EUC_KR, "EUC-KR"},
60  {PG_EUC_KR, "eucKR"},
61  {PG_EUC_KR, "IBM-eucKR"},
62  {PG_EUC_KR, "deckorean"},
63  {PG_EUC_KR, "5601"},
64  {PG_EUC_KR, "CP51949"},
65 
66  {PG_EUC_TW, "EUC-TW"},
67  {PG_EUC_TW, "eucTW"},
68  {PG_EUC_TW, "IBM-eucTW"},
69  {PG_EUC_TW, "cns11643"},
70  /* No codepage for EUC-TW ? */
71 
72  {PG_UTF8, "UTF-8"},
73  {PG_UTF8, "utf8"},
74  {PG_UTF8, "CP65001"},
75 
76  {PG_LATIN1, "ISO-8859-1"},
77  {PG_LATIN1, "ISO8859-1"},
78  {PG_LATIN1, "iso88591"},
79  {PG_LATIN1, "CP28591"},
80 
81  {PG_LATIN2, "ISO-8859-2"},
82  {PG_LATIN2, "ISO8859-2"},
83  {PG_LATIN2, "iso88592"},
84  {PG_LATIN2, "CP28592"},
85 
86  {PG_LATIN3, "ISO-8859-3"},
87  {PG_LATIN3, "ISO8859-3"},
88  {PG_LATIN3, "iso88593"},
89  {PG_LATIN3, "CP28593"},
90 
91  {PG_LATIN4, "ISO-8859-4"},
92  {PG_LATIN4, "ISO8859-4"},
93  {PG_LATIN4, "iso88594"},
94  {PG_LATIN4, "CP28594"},
95 
96  {PG_LATIN5, "ISO-8859-9"},
97  {PG_LATIN5, "ISO8859-9"},
98  {PG_LATIN5, "iso88599"},
99  {PG_LATIN5, "CP28599"},
100 
101  {PG_LATIN6, "ISO-8859-10"},
102  {PG_LATIN6, "ISO8859-10"},
103  {PG_LATIN6, "iso885910"},
104 
105  {PG_LATIN7, "ISO-8859-13"},
106  {PG_LATIN7, "ISO8859-13"},
107  {PG_LATIN7, "iso885913"},
108 
109  {PG_LATIN8, "ISO-8859-14"},
110  {PG_LATIN8, "ISO8859-14"},
111  {PG_LATIN8, "iso885914"},
112 
113  {PG_LATIN9, "ISO-8859-15"},
114  {PG_LATIN9, "ISO8859-15"},
115  {PG_LATIN9, "iso885915"},
116  {PG_LATIN9, "CP28605"},
117 
118  {PG_LATIN10, "ISO-8859-16"},
119  {PG_LATIN10, "ISO8859-16"},
120  {PG_LATIN10, "iso885916"},
121 
122  {PG_KOI8R, "KOI8-R"},
123  {PG_KOI8R, "CP20866"},
124 
125  {PG_KOI8U, "KOI8-U"},
126  {PG_KOI8U, "CP21866"},
127 
128  {PG_WIN866, "CP866"},
129  {PG_WIN874, "CP874"},
130  {PG_WIN1250, "CP1250"},
131  {PG_WIN1251, "CP1251"},
132  {PG_WIN1251, "ansi-1251"},
133  {PG_WIN1252, "CP1252"},
134  {PG_WIN1253, "CP1253"},
135  {PG_WIN1254, "CP1254"},
136  {PG_WIN1255, "CP1255"},
137  {PG_WIN1256, "CP1256"},
138  {PG_WIN1257, "CP1257"},
139  {PG_WIN1258, "CP1258"},
140 
141  {PG_ISO_8859_5, "ISO-8859-5"},
142  {PG_ISO_8859_5, "ISO8859-5"},
143  {PG_ISO_8859_5, "iso88595"},
144  {PG_ISO_8859_5, "CP28595"},
145 
146  {PG_ISO_8859_6, "ISO-8859-6"},
147  {PG_ISO_8859_6, "ISO8859-6"},
148  {PG_ISO_8859_6, "iso88596"},
149  {PG_ISO_8859_6, "CP28596"},
150 
151  {PG_ISO_8859_7, "ISO-8859-7"},
152  {PG_ISO_8859_7, "ISO8859-7"},
153  {PG_ISO_8859_7, "iso88597"},
154  {PG_ISO_8859_7, "CP28597"},
155 
156  {PG_ISO_8859_8, "ISO-8859-8"},
157  {PG_ISO_8859_8, "ISO8859-8"},
158  {PG_ISO_8859_8, "iso88598"},
159  {PG_ISO_8859_8, "CP28598"},
160 
161  {PG_SJIS, "SJIS"},
162  {PG_SJIS, "PCK"},
163  {PG_SJIS, "CP932"},
164  {PG_SJIS, "SHIFT_JIS"},
165 
166  {PG_BIG5, "BIG5"},
167  {PG_BIG5, "BIG5HKSCS"},
168  {PG_BIG5, "Big5-HKSCS"},
169  {PG_BIG5, "CP950"},
170 
171  {PG_GBK, "GBK"},
172  {PG_GBK, "CP936"},
173 
174  {PG_UHC, "UHC"},
175  {PG_UHC, "CP949"},
176 
177  {PG_JOHAB, "JOHAB"},
178  {PG_JOHAB, "CP1361"},
179 
180  {PG_GB18030, "GB18030"},
181  {PG_GB18030, "CP54936"},
182 
183  {PG_SHIFT_JIS_2004, "SJIS_2004"},
184 
185  {PG_SQL_ASCII, "US-ASCII"},
186 
187  {PG_SQL_ASCII, NULL} /* end marker */
188 };
189 
190 #ifdef WIN32
191 /*
192  * On Windows, use CP<code page number> instead of the nl_langinfo() result
193  *
194  * Visual Studio 2012 expanded the set of valid LC_CTYPE values, so have its
195  * locale machinery determine the code page. See comments at IsoLocaleName().
196  * For other compilers, follow the locale's predictable format.
197  *
198  * Visual Studio 2015 should still be able to do the same, but the declaration
199  * of lc_codepage is missing in _locale_t, causing this code compilation to
200  * fail, hence this falls back instead on GetLocaleInfoEx. VS 2015 may be an
201  * exception and post-VS2015 versions should be able to handle properly the
202  * codepage number using _create_locale(). So, instead of the same logic as
203  * VS 2012 and VS 2013, this routine uses GetLocaleInfoEx to parse short
204  * locale names like "de-DE", "fr-FR", etc. If those cannot be parsed correctly
205  * process falls back to the pre-VS-2010 manual parsing done with
206  * using <Language>_<Country>.<CodePage> as a base.
207  *
208  * Returns a malloc()'d string for the caller to free.
209  */
210 static char *
211 win32_langinfo(const char *ctype)
212 {
213  char *r = NULL;
214 
215 #if defined(_MSC_VER) && (_MSC_VER < 1900)
216  _locale_t loct = NULL;
217 
218  loct = _create_locale(LC_CTYPE, ctype);
219  if (loct != NULL)
220  {
221  r = malloc(16); /* excess */
222  if (r != NULL)
223  sprintf(r, "CP%u", loct->locinfo->lc_codepage);
224  _free_locale(loct);
225  }
226 #else
227  char *codepage;
228 
229 #if defined(_MSC_VER) && (_MSC_VER >= 1900)
230  uint32 cp;
231  WCHAR wctype[LOCALE_NAME_MAX_LENGTH];
232 
233  memset(wctype, 0, sizeof(wctype));
234  MultiByteToWideChar(CP_ACP, 0, ctype, -1, wctype, LOCALE_NAME_MAX_LENGTH);
235 
236  if (GetLocaleInfoEx(wctype,
237  LOCALE_IDEFAULTANSICODEPAGE | LOCALE_RETURN_NUMBER,
238  (LPWSTR) &cp, sizeof(cp) / sizeof(WCHAR)) > 0)
239  {
240  r = malloc(16); /* excess */
241  if (r != NULL)
242  {
243  /*
244  * If the return value is CP_ACP that means no ANSI code page is
245  * available, so only Unicode can be used for the locale.
246  */
247  if (cp == CP_ACP)
248  strcpy(r, "utf8");
249  else
250  sprintf(r, "CP%u", cp);
251  }
252  }
253  else
254 #endif
255  {
256  /*
257  * Locale format on Win32 is <Language>_<Country>.<CodePage>. For
258  * example, English_United States.1252. If we see digits after the
259  * last dot, assume it's a codepage number. Otherwise, we might be
260  * dealing with a Unix-style locale string; Windows' setlocale() will
261  * take those even though GetLocaleInfoEx() won't, so we end up here.
262  * In that case, just return what's after the last dot and hope we can
263  * find it in our table.
264  */
265  codepage = strrchr(ctype, '.');
266  if (codepage != NULL)
267  {
268  size_t ln;
269 
270  codepage++;
271  ln = strlen(codepage);
272  r = malloc(ln + 3);
273  if (r != NULL)
274  {
275  if (strspn(codepage, "0123456789") == ln)
276  sprintf(r, "CP%s", codepage);
277  else
278  strcpy(r, codepage);
279  }
280  }
281 
282  }
283 #endif
284 
285  return r;
286 }
287 
288 #ifndef FRONTEND
289 /*
290  * Given a Windows code page identifier, find the corresponding PostgreSQL
291  * encoding. Issue a warning and return -1 if none found.
292  */
293 int
294 pg_codepage_to_encoding(UINT cp)
295 {
296  char sys[16];
297  int i;
298 
299  sprintf(sys, "CP%u", cp);
300 
301  /* Check the table */
302  for (i = 0; encoding_match_list[i].system_enc_name; i++)
303  if (pg_strcasecmp(sys, encoding_match_list[i].system_enc_name) == 0)
304  return encoding_match_list[i].pg_enc_code;
305 
307  (errmsg("could not determine encoding for codeset \"%s\"", sys)));
308 
309  return -1;
310 }
311 #endif
312 #endif /* WIN32 */
313 
314 #if (defined(HAVE_LANGINFO_H) && defined(CODESET)) || defined(WIN32)
315 
316 /*
317  * Given a setting for LC_CTYPE, return the Postgres ID of the associated
318  * encoding, if we can determine it. Return -1 if we can't determine it.
319  *
320  * Pass in NULL to get the encoding for the current locale setting.
321  * Pass "" to get the encoding selected by the server's environment.
322  *
323  * If the result is PG_SQL_ASCII, callers should treat it as being compatible
324  * with any desired encoding.
325  *
326  * If running in the backend and write_message is false, this function must
327  * cope with the possibility that elog() and palloc() are not yet usable.
328  */
329 int
330 pg_get_encoding_from_locale(const char *ctype, bool write_message)
331 {
332  char *sys;
333  int i;
334 
335  /* Get the CODESET property, and also LC_CTYPE if not passed in */
336  if (ctype)
337  {
338  char *save;
339  char *name;
340 
341  /* If locale is C or POSIX, we can allow all encodings */
342  if (pg_strcasecmp(ctype, "C") == 0 ||
343  pg_strcasecmp(ctype, "POSIX") == 0)
344  return PG_SQL_ASCII;
345 
346  save = setlocale(LC_CTYPE, NULL);
347  if (!save)
348  return -1; /* setlocale() broken? */
349  /* must copy result, or it might change after setlocale */
350  save = strdup(save);
351  if (!save)
352  return -1; /* out of memory; unlikely */
353 
354  name = setlocale(LC_CTYPE, ctype);
355  if (!name)
356  {
357  free(save);
358  return -1; /* bogus ctype passed in? */
359  }
360 
361 #ifndef WIN32
362  sys = nl_langinfo(CODESET);
363  if (sys)
364  sys = strdup(sys);
365 #else
366  sys = win32_langinfo(name);
367 #endif
368 
369  setlocale(LC_CTYPE, save);
370  free(save);
371  }
372  else
373  {
374  /* much easier... */
375  ctype = setlocale(LC_CTYPE, NULL);
376  if (!ctype)
377  return -1; /* setlocale() broken? */
378 
379  /* If locale is C or POSIX, we can allow all encodings */
380  if (pg_strcasecmp(ctype, "C") == 0 ||
381  pg_strcasecmp(ctype, "POSIX") == 0)
382  return PG_SQL_ASCII;
383 
384 #ifndef WIN32
385  sys = nl_langinfo(CODESET);
386  if (sys)
387  sys = strdup(sys);
388 #else
389  sys = win32_langinfo(ctype);
390 #endif
391  }
392 
393  if (!sys)
394  return -1; /* out of memory; unlikely */
395 
396  /* Check the table */
397  for (i = 0; encoding_match_list[i].system_enc_name; i++)
398  {
399  if (pg_strcasecmp(sys, encoding_match_list[i].system_enc_name) == 0)
400  {
401  free(sys);
402  return encoding_match_list[i].pg_enc_code;
403  }
404  }
405 
406  /* Special-case kluges for particular platforms go here */
407 
408 #ifdef __darwin__
409 
410  /*
411  * Current macOS has many locales that report an empty string for CODESET,
412  * but they all seem to actually use UTF-8.
413  */
414  if (strlen(sys) == 0)
415  {
416  free(sys);
417  return PG_UTF8;
418  }
419 #endif
420 
421  /*
422  * We print a warning if we got a CODESET string but couldn't recognize
423  * it. This means we need another entry in the table.
424  */
425  if (write_message)
426  {
427 #ifdef FRONTEND
428  fprintf(stderr, _("could not determine encoding for locale \"%s\": codeset is \"%s\""),
429  ctype, sys);
430  /* keep newline separate so there's only one translatable string */
431  fputc('\n', stderr);
432 #else
434  (errmsg("could not determine encoding for locale \"%s\": codeset is \"%s\"",
435  ctype, sys)));
436 #endif
437  }
438 
439  free(sys);
440  return -1;
441 }
442 #else /* (HAVE_LANGINFO_H && CODESET) || WIN32 */
443 
444 /*
445  * stub if no multi-language platform support
446  *
447  * Note: we could return -1 here, but that would have the effect of
448  * forcing users to specify an encoding to initdb on such platforms.
449  * It seems better to silently default to SQL_ASCII.
450  */
451 int
452 pg_get_encoding_from_locale(const char *ctype, bool write_message)
453 {
454  return PG_SQL_ASCII;
455 }
456 
457 #endif /* (HAVE_LANGINFO_H && CODESET) || WIN32 */
enum pg_enc pg_enc_code
Definition: chklocale.c:41
#define setlocale(a, b)
Definition: win32_port.h:436
int pg_strcasecmp(const char *s1, const char *s2)
Definition: pgstrcasecmp.c:36
#define fprintf
Definition: port.h:219
#define malloc(a)
Definition: header.h:50
#define sprintf
Definition: port.h:217
const char * system_enc_name
Definition: chklocale.c:42
unsigned int uint32
Definition: c.h:375
static const struct encoding_match encoding_match_list[]
Definition: chklocale.c:45
#define WARNING
Definition: elog.h:40
#define ereport(elevel,...)
Definition: elog.h:144
#define free(a)
Definition: header.h:65
pg_enc
Definition: pg_wchar.h:238
int pg_get_encoding_from_locale(const char *ctype, bool write_message)
Definition: chklocale.c:452
const char * name
Definition: encode.c:561
int errmsg(const char *fmt,...)
Definition: elog.c:821
int i
#define _(x)
Definition: elog.c:88