Change wchar2char() and char2wchar() to accept a locale_t.

These are libc-specific functions, so should require a locale_t rather
than a pg_locale_t (which could use another provider).

Discussion: https://postgr.es/m/a8666c391dfcabe79868d95f7160eac533ace718.camel%40j-davis.com

src/backend/tsearch/ts_locale.c

@@ -36,7 +36,7 @@ t_isalpha(const char *ptr)
 {
 	int			clen = pg_mblen(ptr);
 	wchar_t		character[WC_BUF_LEN];
-	pg_locale_t mylocale = 0;	/* TODO */
+	locale_t	mylocale = 0;	/* TODO */
 
 	if (clen == 1 || database_ctype_is_c)
 		return isalpha(TOUCHAR(ptr));
@@ -51,7 +51,7 @@ t_isalnum(const char *ptr)
 {
 	int			clen = pg_mblen(ptr);
 	wchar_t		character[WC_BUF_LEN];
-	pg_locale_t mylocale = 0;	/* TODO */
+	locale_t	mylocale = 0;	/* TODO */
 
 	if (clen == 1 || database_ctype_is_c)
 		return isalnum(TOUCHAR(ptr));

src/backend/tsearch/wparser_def.c

@@ -299,7 +299,7 @@ TParserInit(char *str, int len)
 	 */
 	if (prs->charmaxlen > 1)
 	{
-		pg_locale_t mylocale = 0;	/* TODO */
+		locale_t	mylocale = 0;	/* TODO */
 
 		prs->usewide = true;
 		if (database_ctype_is_c)

src/backend/utils/adt/pg_locale_libc.c

@@ -457,7 +457,7 @@ strlower_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 		workspace[curr_char] = towlower_l(workspace[curr_char], loc);
@@ -468,7 +468,7 @@ strlower_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -552,7 +552,7 @@ strtitle_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 	{
@@ -569,7 +569,7 @@ strtitle_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -640,7 +640,7 @@ strupper_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 		workspace[curr_char] = towupper_l(workspace[curr_char], loc);
@@ -651,7 +651,7 @@ strupper_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -1130,7 +1130,7 @@ wcstombs_l(char *dest, const wchar_t *src, size_t n, locale_t loc)
  * zero-terminated.  The output will be zero-terminated iff there is room.
  */
 size_t
-wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
+wchar2char(char *to, const wchar_t *from, size_t tolen, locale_t loc)
 {
 	size_t		result;
 
@@ -1160,7 +1160,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
 	}
 	else
 #endif							/* WIN32 */
-	if (locale == (pg_locale_t) 0)
+	if (loc == (locale_t) 0)
 	{
 		/* Use wcstombs directly for the default locale */
 		result = wcstombs(to, from, tolen);
@@ -1168,7 +1168,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
 	else
 	{
 		/* Use wcstombs_l for nondefault locales */
-		result = wcstombs_l(to, from, tolen, locale->info.lt);
+		result = wcstombs_l(to, from, tolen, loc);
 	}
 
 	return result;
@@ -1185,7 +1185,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
  */
 size_t
 char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
-		   pg_locale_t locale)
+		   locale_t loc)
 {
 	size_t		result;
 
@@ -1220,7 +1220,7 @@ char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
 		/* mbstowcs requires ending '\0' */
 		char	   *str = pnstrdup(from, fromlen);
 
-		if (locale == (pg_locale_t) 0)
+		if (loc == (locale_t) 0)
 		{
 			/* Use mbstowcs directly for the default locale */
 			result = mbstowcs(to, str, tolen);
@@ -1228,7 +1228,7 @@ char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
 		else
 		{
 			/* Use mbstowcs_l for nondefault locales */
-			result = mbstowcs_l(to, str, tolen, locale->info.lt);
+			result = mbstowcs_l(to, str, tolen, loc);
 		}
 
 		pfree(str);

src/include/utils/pg_locale.h

@@ -214,8 +214,8 @@ extern void report_newlocale_failure(const char *localename);
 
 /* These functions convert from/to libc's wchar_t, *not* pg_wchar_t */
 extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen,
-						 pg_locale_t locale);
+						 locale_t loc);
 extern size_t char2wchar(wchar_t *to, size_t tolen,
-						 const char *from, size_t fromlen, pg_locale_t locale);
+						 const char *from, size_t fromlen, locale_t loc);
 
 #endif							/* _PG_LOCALE_ */