@ -99,15 +99,24 @@ static char lc_monetary_envbuf[LC_ENV_BUFSIZE];
static char lc_numeric_envbuf [ LC_ENV_BUFSIZE ] ;
static char lc_time_envbuf [ LC_ENV_BUFSIZE ] ;
/* Cache for collation-related knowledge */
typedef struct
{
Oid collid ; /* hash key: pg_collation OID */
bool collate_is_c ; /* is collation's LC_COLLATE C? */
bool ctype_is_c ; /* is collation's LC_CTYPE C? */
bool flags_valid ; /* true if above flags are valid */
pg_locale_t locale ; /* locale_t struct, or 0 if not valid */
} collation_cache_entry ;
static HTAB * collation_cache = NULL ;
# if defined(WIN32) && defined(LC_MESSAGES)
static char * IsoLocaleName ( const char * ) ; /* MSVC specific */
# endif
static HTAB * locale_cness_cache = NULL ;
# ifdef HAVE_LOCALE_T
static HTAB * locale_t_cache = NULL ;
# endif
/*
* pg_perm_setlocale
@ -312,136 +321,6 @@ locale_messages_assign(const char *value, bool doit, GucSource source)
}
/*
* We ' d like to cache whether LC_COLLATE or LC_CTYPE is C ( or POSIX ) ,
* so we can optimize a few code paths in various places .
*
* Note that some code relies on this not reporting false negatives
* ( that is , saying it ' s not C when it is ) . For example , char2wchar ( )
* could fail if the locale is C , so str_tolower ( ) shouldn ' t call it
* in that case .
*/
struct locale_cness_cache_entry
{
Oid collid ;
bool collate_is_c ;
bool ctype_is_c ;
} ;
static void
init_locale_cness_cache ( void )
{
HASHCTL ctl ;
memset ( & ctl , 0 , sizeof ( ctl ) ) ;
ctl . keysize = sizeof ( Oid ) ;
ctl . entrysize = sizeof ( struct locale_cness_cache_entry ) ;
ctl . hash = oid_hash ;
locale_cness_cache = hash_create ( " locale C-ness cache " , 1000 , & ctl , HASH_ELEM | HASH_FUNCTION ) ;
}
/*
* Handle caching of locale " C-ness " for nondefault collation objects .
* Relying on the system cache directly isn ' t fast enough .
*/
static bool
lookup_collation_cness ( Oid collation , int category )
{
struct locale_cness_cache_entry * cache_entry ;
bool found ;
HeapTuple tp ;
char * localeptr ;
Assert ( OidIsValid ( collation ) ) ;
Assert ( category = = LC_COLLATE | | category = = LC_CTYPE ) ;
if ( ! locale_cness_cache )
init_locale_cness_cache ( ) ;
cache_entry = hash_search ( locale_cness_cache , & collation , HASH_ENTER , & found ) ;
if ( found )
{
if ( category = = LC_COLLATE )
return cache_entry - > collate_is_c ;
else
return cache_entry - > ctype_is_c ;
}
tp = SearchSysCache1 ( COLLOID , ObjectIdGetDatum ( collation ) ) ;
if ( ! HeapTupleIsValid ( tp ) )
elog ( ERROR , " cache lookup failed for collation %u " , collation ) ;
localeptr = NameStr ( ( ( Form_pg_collation ) GETSTRUCT ( tp ) ) - > collcollate ) ;
cache_entry - > collate_is_c = ( strcmp ( localeptr , " C " ) = = 0 ) | | ( strcmp ( localeptr , " POSIX " ) = = 0 ) ;
localeptr = NameStr ( ( ( Form_pg_collation ) GETSTRUCT ( tp ) ) - > collctype ) ;
cache_entry - > ctype_is_c = ( strcmp ( localeptr , " C " ) = = 0 ) | | ( strcmp ( localeptr , " POSIX " ) = = 0 ) ;
ReleaseSysCache ( tp ) ;
return category = = LC_COLLATE ? cache_entry - > collate_is_c : cache_entry - > ctype_is_c ;
}
bool
lc_collate_is_c ( Oid collation )
{
/* Cache result so we only have to compute it once */
static int result = - 1 ;
char * localeptr ;
if ( ! OidIsValid ( collation ) )
return false ;
if ( collation ! = DEFAULT_COLLATION_OID )
return lookup_collation_cness ( collation , LC_COLLATE ) ;
if ( result > = 0 )
return ( bool ) result ;
localeptr = setlocale ( LC_COLLATE , NULL ) ;
if ( ! localeptr )
elog ( ERROR , " invalid LC_COLLATE setting " ) ;
if ( strcmp ( localeptr , " C " ) = = 0 )
result = true ;
else if ( strcmp ( localeptr , " POSIX " ) = = 0 )
result = true ;
else
result = false ;
return ( bool ) result ;
}
bool
lc_ctype_is_c ( Oid collation )
{
/* Cache result so we only have to compute it once */
static int result = - 1 ;
char * localeptr ;
if ( ! OidIsValid ( collation ) )
return false ;
if ( collation ! = DEFAULT_COLLATION_OID )
return lookup_collation_cness ( collation , LC_CTYPE ) ;
if ( result > = 0 )
return ( bool ) result ;
localeptr = setlocale ( LC_CTYPE , NULL ) ;
if ( ! localeptr )
elog ( ERROR , " invalid LC_CTYPE setting " ) ;
if ( strcmp ( localeptr , " C " ) = = 0 )
result = true ;
else if ( strcmp ( localeptr , " POSIX " ) = = 0 )
result = true ;
else
result = false ;
return ( bool ) result ;
}
/*
* Frees the malloced content of a struct lconv . ( But not the struct
* itself . )
@ -844,116 +723,295 @@ IsoLocaleName(const char *winlocname)
# endif /* WIN32 && LC_MESSAGES */
# ifdef HAVE_LOCALE_T
struct locale_t_cache_entry
/*
* Cache mechanism for collation information .
*
* We cache 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 .
*
* Also , if a pg_locale_t has been requested for a collation , we cache that
* for the life of a backend .
*
* Note that some code relies on the flags not reporting false negatives
* ( that is , saying it ' s not C when it is ) . For example , char2wchar ( )
* could fail if the locale is C , so str_tolower ( ) shouldn ' t call it
* in that case .
*
* Note that we currently lack any way to flush the cache . Since we don ' t
* support ALTER COLLATION , this is OK . The worst case is that someone
* drops a collation , and a useless cache entry hangs around in existing
* backends .
*/
static collation_cache_entry *
lookup_collation_cache ( Oid collation , bool set_flags )
{
Oid collid ;
locale_t locale ;
} ;
collation_cache_entry * cache_entry ;
bool found ;
static void
init_locale_t_cache ( void )
Assert ( OidIsValid ( collation ) ) ;
Assert ( collation ! = DEFAULT_COLLATION_OID ) ;
if ( collation_cache = = NULL )
{
/* First time through, initialize the hash table */
HASHCTL ctl ;
memset ( & ctl , 0 , sizeof ( ctl ) ) ;
ctl . keysize = sizeof ( Oid ) ;
ctl . entrysize = sizeof ( struct locale_t_cache_entry ) ;
ctl . entrysize = sizeof ( collation _cache_entry) ;
ctl . hash = oid_hash ;
locale_t_cache = hash_create ( " locale_t cache " , 1000 , & ctl , HASH_ELEM | HASH_FUNCTION ) ;
collation_cache = hash_create ( " Collation cache " , 100 , & ctl ,
HASH_ELEM | HASH_FUNCTION ) ;
}
cache_entry = hash_search ( collation_cache , & collation , HASH_ENTER , & found ) ;
if ( ! found )
{
/*
* Make sure cache entry is marked invalid , in case we fail before
* setting things .
*/
cache_entry - > flags_valid = false ;
cache_entry - > locale = 0 ;
}
# endif /* HAVE_LOCALE_T */
if ( set_flags & & ! cache_entry - > flags_valid )
{
/* Attempt to set the flags */
HeapTuple tp ;
Form_pg_collation collform ;
const char * collcollate ;
const char * collctype ;
tp = SearchSysCache1 ( COLLOID , ObjectIdGetDatum ( collation ) ) ;
if ( ! HeapTupleIsValid ( tp ) )
elog ( ERROR , " cache lookup failed for collation %u " , collation ) ;
collform = ( Form_pg_collation ) GETSTRUCT ( tp ) ;
collcollate = NameStr ( collform - > collcollate ) ;
collctype = NameStr ( collform - > collctype ) ;
cache_entry - > collate_is_c = ( ( strcmp ( collcollate , " C " ) = = 0 ) | |
( strcmp ( collcollate , " POSIX " ) = = 0 ) ) ;
cache_entry - > ctype_is_c = ( ( strcmp ( collctype , " C " ) = = 0 ) | |
( strcmp ( collctype , " POSIX " ) = = 0 ) ) ;
cache_entry - > flags_valid = true ;
ReleaseSysCache ( tp ) ;
}
return cache_entry ;
}
/*
* Detect whether collation ' s LC_COLLATE property is C
*/
bool
lc_collate_is_c ( Oid collation )
{
/*
* If we ' re asked about " collation 0 " , return false , so that the code
* will go into the non - C path and report that the collation is bogus .
*/
if ( ! OidIsValid ( collation ) )
return false ;
/*
* If we ' re asked about the default collation , we have to inquire of
* the C library . Cache the result so we only have to compute it once .
*/
if ( collation = = DEFAULT_COLLATION_OID )
{
static int result = - 1 ;
char * localeptr ;
if ( result > = 0 )
return ( bool ) result ;
localeptr = setlocale ( LC_COLLATE , NULL ) ;
if ( ! localeptr )
elog ( ERROR , " invalid LC_COLLATE setting " ) ;
if ( strcmp ( localeptr , " C " ) = = 0 )
result = true ;
else if ( strcmp ( localeptr , " POSIX " ) = = 0 )
result = true ;
else
result = false ;
return ( bool ) result ;
}
/*
* If we ' re asked about the built - in C / POSIX collations , we know that .
*/
if ( collation = = C_COLLATION_OID | |
collation = = POSIX_COLLATION_OID )
return true ;
/*
* Otherwise , we have to consult pg_collation , but we cache that .
*/
return ( lookup_collation_cache ( collation , true ) ) - > collate_is_c ;
}
/*
* Detect whether collation ' s LC_CTYPE property is C
*/
bool
lc_ctype_is_c ( Oid collation )
{
/*
* If we ' re asked about " collation 0 " , return false , so that the code
* will go into the non - C path and report that the collation is bogus .
*/
if ( ! OidIsValid ( collation ) )
return false ;
/*
* If we ' re asked about the default collation , we have to inquire of
* the C library . Cache the result so we only have to compute it once .
*/
if ( collation = = DEFAULT_COLLATION_OID )
{
static int result = - 1 ;
char * localeptr ;
if ( result > = 0 )
return ( bool ) result ;
localeptr = setlocale ( LC_CTYPE , NULL ) ;
if ( ! localeptr )
elog ( ERROR , " invalid LC_CTYPE setting " ) ;
if ( strcmp ( localeptr , " C " ) = = 0 )
result = true ;
else if ( strcmp ( localeptr , " POSIX " ) = = 0 )
result = true ;
else
result = false ;
return ( bool ) result ;
}
/*
* If we ' re asked about the built - in C / POSIX collations , we know that .
*/
if ( collation = = C_COLLATION_OID | |
collation = = POSIX_COLLATION_OID )
return true ;
/*
* Otherwise , we have to consult pg_collation , but we cache that .
*/
return ( lookup_collation_cache ( collation , true ) ) - > ctype_is_c ;
}
/*
* Create a locale_t from a collation OID . Results are cached for the
* lifetime of the backend . Thus , do not free the result with
* freelocale ( ) .
* lifetime of the backend . Thus , do not free the result with freelocale ( ) .
*
* As a special optimization , the default / database collation returns
* 0. Callers should then revert to the non - locale_t - enabled code
* path . In fact , they shouldn ' t call this function at all when they
* are dealing with the default locale . That can save quite a bit in
* hotspots .
* As a special optimization , the default / database collation returns 0.
* Callers should then revert to the non - locale_t - enabled code path .
* In fact , they shouldn ' t call this function at all when they are dealing
* with the default locale . That can save quite a bit in hotspots .
* Also , callers should avoid calling this before going down a C / POSIX
* fastpath , because such a fastpath should work even on platforms without
* locale_t support in the C library .
*
* For simplicity , we always generate COLLATE + CTYPE even though we
* might only need one of them . Since this is called only once per
* session , it shouldn ' t cost much .
* might only need one of them . Since this is called only once per session ,
* it shouldn ' t cost much .
*/
pg_locale_t
pg_newlocale_from_collation ( Oid collid )
{
# ifdef HAVE_LOCALE_T
HeapTuple tp ;
const char * collcollate ;
const char * collctype ;
locale_t result ;
struct locale_t_cache_entry * cache_entry ;
bool found ;
collation_cache_entry * cache_entry ;
/* Return 0 for "default" collation, just in case caller forgets */
if ( collid = = DEFAULT_COLLATION_OID )
return ( locale_t ) 0 ;
return ( pg_locale_t ) 0 ;
/*
* This is where we ' ll fail if a collation - aware function is invoked
* and no collation OID is passed . This typically means that the
* parser could not resolve a conflict of implicit collations , so
* report it that way .
*/
if ( ! OidIsValid ( collid ) )
elog ( ERROR , " locale operation to be invoked, but no collation was derived " ) ;
ereport ( ERROR ,
( errcode ( ERRCODE_INDETERMINATE_COLLATION ) ,
errmsg ( " locale operation to be invoked, but no collation was derived " ) ) ) ;
if ( ! locale_t_cache )
init_locale_t_cache ( ) ;
cache_entry = lookup_collation_cache ( collid , false ) ;
cache_entry = hash_search ( locale_t_cache , & collid , HASH_ENTER , & found ) ;
if ( found )
return cache_entry - > locale ;
if ( cache_entry - > locale = = 0 )
{
/* We haven't computed this yet in this session, so do it */
# ifdef HAVE_LOCALE_T
HeapTuple tp ;
Form_pg_collation collform ;
const char * collcollate ;
const char * collctype ;
locale_t result ;
tp = SearchSysCache1 ( COLLOID , ObjectIdGetDatum ( collid ) ) ;
if ( ! HeapTupleIsValid ( tp ) )
elog ( ERROR , " cache lookup failed for collation %u " , collid ) ;
collform = ( Form_pg_collation ) GETSTRUCT ( tp ) ;
collcollate = NameStr ( ( ( Form_pg_collation ) GETSTRUCT ( tp ) ) - > collcollate ) ;
collctype = NameStr ( ( ( Form_pg_collation ) GETSTRUCT ( tp ) ) - > collctype ) ;
collcollate = NameStr ( collform - > collcollate ) ;
collctype = NameStr ( collform - > collctype ) ;
if ( strcmp ( collcollate , collctype ) = = 0 )
{
result = newlocale ( LC_COLLATE_MASK | LC_CTYPE_MASK , collcollate , NULL ) ;
/* Normal case where they're the same */
result = newlocale ( LC_COLLATE_MASK | LC_CTYPE_MASK , collcollate ,
NULL ) ;
if ( ! result )
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not create locale \" %s \" : %m " , collcollate ) ) ) ;
errmsg ( " could not create locale \" %s \" : %m " ,
collcollate ) ) ) ;
}
else
{
/* We need two newlocale() steps */
locale_t loc1 ;
loc1 = newlocale ( LC_COLLATE_MASK , collcollate , NULL ) ;
if ( ! loc1 )
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not create locale \" %s \" : %m " , collcollate ) ) ) ;
errmsg ( " could not create locale \" %s \" : %m " ,
collcollate ) ) ) ;
result = newlocale ( LC_CTYPE_MASK , collctype , loc1 ) ;
if ( ! result )
ereport ( ERROR ,
( errcode_for_file_access ( ) ,
errmsg ( " could not create locale \" %s \" : %m " , collctype ) ) ) ;
errmsg ( " could not create locale \" %s \" : %m " ,
collctype ) ) ) ;
}
ReleaseSysCache ( tp ) ;
cache_entry - > locale = result ;
return result ;
ReleaseSysCache ( tp ) ;
# else /* not HAVE_LOCALE_T */
/*
* For platforms that don ' t support locale_t , check that we are
* dealing with the default locale . It ' s unlikely that we ' ll get
* here , but it ' s possible if users are creating collations even
* though they are not supported , or they are mixing builds in odd
* ways .
* For platforms that don ' t support locale_t , we can ' t do anything
* with non - default collations .
*/
if ( ! OidIsValid ( collid ) )
elog ( ERROR , " locale operation to be invoked, but no collation was derived " ) ;
else if ( collid ! = DEFAULT_COLLATION_OID )
ereport ( ERROR ,
( errcode ( ERRCODE_FEATURE_NOT_SUPPORTED ) ,
errmsg ( " nondefault collations are not supported on this platform " ) ) ) ;
return 0 ;
# endif /* not HAVE_LOCALE_T */
}
return cache_entry - > locale ;
}
Tom Lane
15 years ago