/*----------------------------------------------------------------------- * * PostgreSQL locale utilities * * src/include/utils/pg_locale.h * * Copyright (c) 2002-2026, PostgreSQL Global Development Group * *----------------------------------------------------------------------- */ #ifndef _PG_LOCALE_ #define _PG_LOCALE_ #include "mb/pg_wchar.h" /* use for libc locale names */ #define LOCALE_NAME_BUFLEN 128 /* * Maximum number of bytes needed to map a single codepoint. Useful for * mapping and processing a single input codepoint at a time with a * statically-allocated buffer. * * With full case mapping, an input codepoint may be mapped to as many as * three output codepoints. See Unicode 16.0.0, section 5.18.2, "Change in * Length": * * https://www.unicode.org/versions/Unicode16.0.0/core-spec/chapter-5/#G29675 */ #define UNICODE_CASEMAP_LEN 3 #define UNICODE_CASEMAP_BUFSZ (UNICODE_CASEMAP_LEN * MAX_MULTIBYTE_CHAR_LEN) /* GUC settings */ extern PGDLLIMPORT char *locale_messages; extern PGDLLIMPORT char *locale_monetary; extern PGDLLIMPORT char *locale_numeric; extern PGDLLIMPORT char *locale_time; extern PGDLLIMPORT int icu_validation_level; /* lc_time localization cache */ extern PGDLLIMPORT char *localized_abbrev_days[]; extern PGDLLIMPORT char *localized_full_days[]; extern PGDLLIMPORT char *localized_abbrev_months[]; extern PGDLLIMPORT char *localized_full_months[]; extern bool check_locale(int category, const char *locale, char **canonname); extern char *pg_perm_setlocale(int category, const char *locale); /* * Return the POSIX lconv struct (contains number/money formatting * information) with locale information for all categories. */ extern struct lconv *PGLC_localeconv(void); extern void cache_locale_time(void); struct pg_locale_struct; typedef struct pg_locale_struct *pg_locale_t; /* methods that define collation behavior */ struct collate_methods { /* required */ int (*strncoll) (const char *arg1, ssize_t len1, const char *arg2, ssize_t len2, pg_locale_t locale); /* required */ size_t (*strnxfrm) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); /* optional */ size_t (*strnxfrm_prefix) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); /* * If the strnxfrm method is not trusted to return the correct results, * set strxfrm_is_safe to false. It set to false, the method will not be * used in most cases, but the planner still expects it to be there for * estimation purposes (where incorrect results are acceptable). */ bool strxfrm_is_safe; }; struct ctype_methods { /* case mapping: LOWER()/INITCAP()/UPPER() */ size_t (*strlower) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); size_t (*strtitle) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); size_t (*strupper) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); size_t (*strfold) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); size_t (*downcase_ident) (char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); /* required */ bool (*wc_isdigit) (pg_wchar wc, pg_locale_t locale); bool (*wc_isalpha) (pg_wchar wc, pg_locale_t locale); bool (*wc_isalnum) (pg_wchar wc, pg_locale_t locale); bool (*wc_isupper) (pg_wchar wc, pg_locale_t locale); bool (*wc_islower) (pg_wchar wc, pg_locale_t locale); bool (*wc_isgraph) (pg_wchar wc, pg_locale_t locale); bool (*wc_isprint) (pg_wchar wc, pg_locale_t locale); bool (*wc_ispunct) (pg_wchar wc, pg_locale_t locale); bool (*wc_isspace) (pg_wchar wc, pg_locale_t locale); bool (*wc_isxdigit) (pg_wchar wc, pg_locale_t locale); bool (*wc_iscased) (pg_wchar wc, pg_locale_t locale); pg_wchar (*wc_toupper) (pg_wchar wc, pg_locale_t locale); pg_wchar (*wc_tolower) (pg_wchar wc, pg_locale_t locale); }; /* * We use a discriminated union to hold either a locale_t or an ICU collator. * pg_locale_t is occasionally checked for truth, so make it a pointer. * * Also, hold two flags: whether the collation's LC_COLLATE or LC_CTYPE is C * (or POSIX), so we can optimize a few code paths in various places. For the * built-in C and POSIX collations, we can know that without even doing a * cache lookup, but we want to support aliases for C/POSIX too. For the * "default" collation, there are separate static cache variables, since * consulting the pg_collation catalog doesn't tell us what we need. * * Note that some code, such as wchar2char(), relies on the flags not * reporting false negatives (that is, saying it's not C when it is). */ struct pg_locale_struct { bool deterministic; bool collate_is_c; bool ctype_is_c; bool is_default; const struct collate_methods *collate; /* NULL if collate_is_c */ const struct ctype_methods *ctype; /* NULL if ctype_is_c */ union { struct { const char *locale; bool casemap_full; } builtin; locale_t lt; #ifdef USE_ICU struct { const char *locale; struct UCollator *ucol; struct UCaseMap *ucasemap; locale_t lt; } icu; #endif }; }; extern void init_database_collation(void); extern pg_locale_t pg_database_locale(void); extern pg_locale_t pg_newlocale_from_collation(Oid collid); extern char *get_collation_actual_version(char collprovider, const char *collcollate); extern size_t pg_strlower(char *dst, size_t dstsize, const char *src, ssize_t srclen, pg_locale_t locale); extern size_t pg_strtitle(char *dst, size_t dstsize, const char *src, ssize_t srclen, pg_locale_t locale); extern size_t pg_strupper(char *dst, size_t dstsize, const char *src, ssize_t srclen, pg_locale_t locale); extern size_t pg_strfold(char *dst, size_t dstsize, const char *src, ssize_t srclen, pg_locale_t locale); extern size_t pg_downcase_ident(char *dst, size_t dstsize, const char *src, ssize_t srclen); extern int pg_strcoll(const char *arg1, const char *arg2, pg_locale_t locale); extern int pg_strncoll(const char *arg1, ssize_t len1, const char *arg2, ssize_t len2, pg_locale_t locale); extern bool pg_strxfrm_enabled(pg_locale_t locale); extern size_t pg_strxfrm(char *dest, const char *src, size_t destsize, pg_locale_t locale); extern size_t pg_strnxfrm(char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); extern bool pg_strxfrm_prefix_enabled(pg_locale_t locale); extern size_t pg_strxfrm_prefix(char *dest, const char *src, size_t destsize, pg_locale_t locale); extern size_t pg_strnxfrm_prefix(char *dest, size_t destsize, const char *src, ssize_t srclen, pg_locale_t locale); extern bool pg_iswdigit(pg_wchar wc, pg_locale_t locale); extern bool pg_iswalpha(pg_wchar wc, pg_locale_t locale); extern bool pg_iswalnum(pg_wchar wc, pg_locale_t locale); extern bool pg_iswupper(pg_wchar wc, pg_locale_t locale); extern bool pg_iswlower(pg_wchar wc, pg_locale_t locale); extern bool pg_iswgraph(pg_wchar wc, pg_locale_t locale); extern bool pg_iswprint(pg_wchar wc, pg_locale_t locale); extern bool pg_iswpunct(pg_wchar wc, pg_locale_t locale); extern bool pg_iswspace(pg_wchar wc, pg_locale_t locale); extern bool pg_iswxdigit(pg_wchar wc, pg_locale_t locale); extern bool pg_iswcased(pg_wchar wc, pg_locale_t locale); extern pg_wchar pg_towupper(pg_wchar wc, pg_locale_t locale); extern pg_wchar pg_towlower(pg_wchar wc, pg_locale_t locale); extern const char *pg_icu_unicode_version(void); extern int builtin_locale_encoding(const char *locale); extern const char *builtin_validate_locale(int encoding, const char *locale); extern void icu_validate_locale(const char *loc_str); extern char *icu_language_tag(const char *loc_str, int elevel); extern void report_newlocale_failure(const char *localename); /* This function converts from libc's wchar_t, *not* pg_wchar */ extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen, locale_t loc); #endif /* _PG_LOCALE_ */