/*-------------------------------------------------------------------------
*
* collationcmds.c
* collation-related commands support code
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/commands/collationcmds.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/htup_details.h"
#include "access/table.h"
#include "access/xact.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/namespace.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_collation.h"
#include "commands/alter.h"
#include "commands/collationcmds.h"
#include "commands/comment.h"
#include "commands/dbcommands.h"
#include "commands/defrem.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/pg_locale.h"
#include "utils/rel.h"
#include "utils/syscache.h"
typedef struct
{
char *localename; /* name of locale, as per "locale -a" */
char *alias; /* shortened alias for same */
int enc; /* encoding */
} CollAliasData;
/*
* CREATE COLLATION
*/
ObjectAddress
DefineCollation(ParseState *pstate, List *names, List *parameters, bool if_not_exists)
{
char *collName;
Oid collNamespace;
AclResult aclresult;
ListCell *pl;
DefElem *fromEl = NULL;
DefElem *localeEl = NULL;
DefElem *lccollateEl = NULL;
DefElem *lcctypeEl = NULL;
DefElem *providerEl = NULL;
DefElem *deterministicEl = NULL;
DefElem *versionEl = NULL;
char *collcollate = NULL;
char *collctype = NULL;
char *collproviderstr = NULL;
bool collisdeterministic = true;
int collencoding = 0;
char collprovider = 0;
char *collversion = NULL;
Oid newoid;
ObjectAddress address;
collNamespace = QualifiedNameGetCreationNamespace(names, &collName);
aclresult = pg_namespace_aclcheck(collNamespace, GetUserId(), ACL_CREATE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_SCHEMA,
get_namespace_name(collNamespace));
foreach(pl, parameters)
{
DefElem *defel = lfirst_node(DefElem, pl);
DefElem **defelp;
if (strcmp(defel->defname, "from") == 0)
defelp = &fromEl;
else if (strcmp(defel->defname, "locale") == 0)
defelp = &localeEl;
else if (strcmp(defel->defname, "lc_collate") == 0)
defelp = &lccollateEl;
else if (strcmp(defel->defname, "lc_ctype") == 0)
defelp = &lcctypeEl;
else if (strcmp(defel->defname, "provider") == 0)
defelp = &providerEl;
else if (strcmp(defel->defname, "deterministic") == 0)
defelp = &deterministicEl;
else if (strcmp(defel->defname, "version") == 0)
defelp = &versionEl;
else
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("collation attribute \"%s\" not recognized",
defel->defname),
parser_errposition(pstate, defel->location)));
break;
}
*defelp = defel;
}
if ((localeEl && (lccollateEl || lcctypeEl))
|| (fromEl && list_length(parameters) != 1))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("conflicting or redundant options")));
if (fromEl)
{
Oid collid;
HeapTuple tp;
collid = get_collation_oid(defGetQualifiedName(fromEl), false);
tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collid));
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for collation %u", collid);
collcollate = pstrdup(NameStr(((Form_pg_collation) GETSTRUCT(tp))->collcollate));
collctype = pstrdup(NameStr(((Form_pg_collation) GETSTRUCT(tp))->collctype));
collprovider = ((Form_pg_collation) GETSTRUCT(tp))->collprovider;
collisdeterministic = ((Form_pg_collation) GETSTRUCT(tp))->collisdeterministic;
collencoding = ((Form_pg_collation) GETSTRUCT(tp))->collencoding;
ReleaseSysCache(tp);
/*
* Copying the "default" collation is not allowed because most code
* checks for DEFAULT_COLLATION_OID instead of COLLPROVIDER_DEFAULT,
* and so having a second collation with COLLPROVIDER_DEFAULT would
* not work and potentially confuse or crash some code. This could be
* fixed with some legwork.
*/
if (collprovider == COLLPROVIDER_DEFAULT)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("collation \"default\" cannot be copied")));
}
if (localeEl)
{
collcollate = defGetString(localeEl);
collctype = defGetString(localeEl);
}
if (lccollateEl)
collcollate = defGetString(lccollateEl);
if (lcctypeEl)
collctype = defGetString(lcctypeEl);
if (providerEl)
collproviderstr = defGetString(providerEl);
if (deterministicEl)
collisdeterministic = defGetBoolean(deterministicEl);
if (versionEl)
collversion = defGetString(versionEl);
if (collproviderstr)
{
if (pg_strcasecmp(collproviderstr, "icu") == 0)
collprovider = COLLPROVIDER_ICU;
else if (pg_strcasecmp(collproviderstr, "libc") == 0)
collprovider = COLLPROVIDER_LIBC;
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("unrecognized collation provider: %s",
collproviderstr)));
}
else if (!fromEl)
collprovider = COLLPROVIDER_LIBC;
if (!collcollate)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("parameter \"lc_collate\" must be specified")));
if (!collctype)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("parameter \"lc_ctype\" must be specified")));
/*
* Nondeterministic collations are currently only supported with ICU
* because that's the only case where it can actually make a difference.
* So we can save writing the code for the other providers.
*/
if (!collisdeterministic && collprovider != COLLPROVIDER_ICU)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("nondeterministic collations not supported with this provider")));
if (!fromEl)
{
if (collprovider == COLLPROVIDER_ICU)
collencoding = -1;
else
{
collencoding = GetDatabaseEncoding();
check_encoding_locale_matches(collencoding, collcollate, collctype);
}
}
if (!collversion)
collversion = get_collation_actual_version(collprovider, collcollate);
newoid = CollationCreate(collName,
collNamespace,
GetUserId(),
collprovider,
collisdeterministic,
collencoding,
collcollate,
collctype,
collversion,
if_not_exists,
false); /* not quiet */
if (!OidIsValid(newoid))
return InvalidObjectAddress;
/*
* Check that the locales can be loaded. NB: pg_newlocale_from_collation
* is only supposed to be called on non-C-equivalent locales.
*/
CommandCounterIncrement();
if (!lc_collate_is_c(newoid) || !lc_ctype_is_c(newoid))
(void) pg_newlocale_from_collation(newoid);
ObjectAddressSet(address, CollationRelationId, newoid);
return address;
}
/*
* Subroutine for ALTER COLLATION SET SCHEMA and RENAME
*
* Is there a collation with the same name of the given collation already in
* the given namespace? If so, raise an appropriate error message.
*/
void
IsThereCollationInNamespace(const char *collname, Oid nspOid)
{
/* make sure the name doesn't already exist in new schema */
if (SearchSysCacheExists3(COLLNAMEENCNSP,
CStringGetDatum(collname),
Int32GetDatum(GetDatabaseEncoding()),
ObjectIdGetDatum(nspOid)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("collation \"%s\" for encoding \"%s\" already exists in schema \"%s\"",
collname, GetDatabaseEncodingName(),
get_namespace_name(nspOid))));
/* mustn't match an any-encoding entry, either */
if (SearchSysCacheExists3(COLLNAMEENCNSP,
CStringGetDatum(collname),
Int32GetDatum(-1),
ObjectIdGetDatum(nspOid)))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("collation \"%s\" already exists in schema \"%s\"",
collname, get_namespace_name(nspOid))));
}
/*
* ALTER COLLATION
*/
ObjectAddress
AlterCollation(AlterCollationStmt *stmt)
{
Relation rel;
Oid collOid;
HeapTuple tup;
Form_pg_collation collForm;
Datum collversion;
bool isnull;
char *oldversion;
char *newversion;
ObjectAddress address;
rel = table_open(CollationRelationId, RowExclusiveLock);
collOid = get_collation_oid(stmt->collname, false);
if (!pg_collation_ownercheck(collOid, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_COLLATION,
NameListToString(stmt->collname));
tup = SearchSysCacheCopy1(COLLOID, ObjectIdGetDatum(collOid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for collation %u", collOid);
collForm = (Form_pg_collation) GETSTRUCT(tup);
collversion = SysCacheGetAttr(COLLOID, tup, Anum_pg_collation_collversion,
&isnull);
oldversion = isnull ? NULL : TextDatumGetCString(collversion);
newversion = get_collation_actual_version(collForm->collprovider, NameStr(collForm->collcollate));
/* cannot change from NULL to non-NULL or vice versa */
if ((!oldversion && newversion) || (oldversion && !newversion))
elog(ERROR, "invalid collation version change");
else if (oldversion && newversion && strcmp(newversion, oldversion) != 0)
{
bool nulls[Natts_pg_collation];
bool replaces[Natts_pg_collation];
Datum values[Natts_pg_collation];
ereport(NOTICE,
(errmsg("changing version from %s to %s",
oldversion, newversion)));
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
memset(replaces, false, sizeof(replaces));
values[Anum_pg_collation_collversion - 1] = CStringGetTextDatum(newversion);
replaces[Anum_pg_collation_collversion - 1] = true;
tup = heap_modify_tuple(tup, RelationGetDescr(rel),
values, nulls, replaces);
}
else
ereport(NOTICE,
(errmsg("version has not changed")));
CatalogTupleUpdate(rel, &tup->t_self, tup);
InvokeObjectPostAlterHook(CollationRelationId, collOid, 0);
ObjectAddressSet(address, CollationRelationId, collOid);
heap_freetuple(tup);
table_close(rel, NoLock);
return address;
}
Datum
pg_collation_actual_version(PG_FUNCTION_ARGS)
{
Oid collid = PG_GETARG_OID(0);
HeapTuple tp;
char *collcollate;
char collprovider;
char *version;
tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collid));
if (!HeapTupleIsValid(tp))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("collation with OID %u does not exist", collid)));
collcollate = pstrdup(NameStr(((Form_pg_collation) GETSTRUCT(tp))->collcollate));
collprovider = ((Form_pg_collation) GETSTRUCT(tp))->collprovider;
ReleaseSysCache(tp);
version = get_collation_actual_version(collprovider, collcollate);
if (version)
PG_RETURN_TEXT_P(cstring_to_text(version));
else
PG_RETURN_NULL();
}
/* will we use "locale -a" in pg_import_system_collations? */
#if defined(HAVE_LOCALE_T) && !defined(WIN32)
#define READ_LOCALE_A_OUTPUT
#endif
#if defined(READ_LOCALE_A_OUTPUT) || defined(USE_ICU)
/*
* Check a string to see if it is pure ASCII
*/
static bool
is_all_ascii(const char *str)
{
while (*str)
{
if (IS_HIGHBIT_SET(*str))
return false;
str++;
}
return true;
}
#endif /* READ_LOCALE_A_OUTPUT || USE_ICU */
#ifdef READ_LOCALE_A_OUTPUT
/*
* "Normalize" a libc locale name, stripping off encoding tags such as
* ".utf8" (e.g., "en_US.utf8" -> "en_US", but "br_FR.iso885915@euro"
* -> "br_FR@euro"). Return true if a new, different name was
* generated.
*/
static bool
normalize_libc_locale_name(char *new, const char *old)
{
char *n = new;
const char *o = old;
bool changed = false;
while (*o)
{
if (*o == '.')
{
/* skip over encoding tag such as ".utf8" or ".UTF-8" */
o++;
while ((*o >= 'A' && *o <= 'Z')
|| (*o >= 'a' && *o <= 'z')
|| (*o >= '0' && *o <= '9')
|| (*o == '-'))
o++;
changed = true;
}
else
*n++ = *o++;
}
*n = '\0';
return changed;
}
/*
* qsort comparator for CollAliasData items
*/
static int
cmpaliases(const void *a, const void *b)
{
const CollAliasData *ca = (const CollAliasData *) a;
const CollAliasData *cb = (const CollAliasData *) b;
/* comparing localename is enough because other fields are derived */
return strcmp(ca->localename, cb->localename);
}
#endif /* READ_LOCALE_A_OUTPUT */
#ifdef USE_ICU
/*
* Get the ICU language tag for a locale name.
* The result is a palloc'd string.
*/
static char *
get_icu_language_tag(const char *localename)
{
char buf[ULOC_FULLNAME_CAPACITY];
UErrorCode status;
status = U_ZERO_ERROR;
uloc_toLanguageTag(localename, buf, sizeof(buf), TRUE, &status);
if (U_FAILURE(status))
ereport(ERROR,
(errmsg("could not convert locale name \"%s\" to language tag: %s",
localename, u_errorName(status))));
return pstrdup(buf);
}
/*
* Get a comment (specifically, the display name) for an ICU locale.
* The result is a palloc'd string, or NULL if we can't get a comment
* or find that it's not all ASCII. (We can *not* accept non-ASCII
* comments, because the contents of template0 must be encoding-agnostic.)
*/
static char *
get_icu_locale_comment(const char *localename)
{
UErrorCode status;
UChar displayname[128];
int32 len_uchar;
int32 i;
char *result;
status = U_ZERO_ERROR;
len_uchar = uloc_getDisplayName(localename, "en",
displayname, lengthof(displayname),
&status);
if (U_FAILURE(status))
return NULL; /* no good reason to raise an error */
/* Check for non-ASCII comment (can't use is_all_ascii for this) */
for (i = 0; i < len_uchar; i++)
{
if (displayname[i] > 127)
return NULL;
}
/* OK, transcribe */
result = palloc(len_uchar + 1);
for (i = 0; i < len_uchar; i++)
result[i] = displayname[i];
result[len_uchar] = '\0';
return result;
}
#endif /* USE_ICU */
/*
* pg_import_system_collations: add known system collations to pg_collation
*/
Datum
pg_import_system_collations(PG_FUNCTION_ARGS)
{
Oid nspid = PG_GETARG_OID(0);
int ncreated = 0;
/* silence compiler warning if we have no locale implementation at all */
(void) nspid;
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to import system collations"))));
/* Load collations known to libc, using "locale -a" to enumerate them */
#ifdef READ_LOCALE_A_OUTPUT
{
FILE *locale_a_handle;
char localebuf[NAMEDATALEN]; /* we assume ASCII so this is fine */
int nvalid = 0;
Oid collid;
CollAliasData *aliases;
int naliases,
maxaliases,
i;
/* expansible array of aliases */
maxaliases = 100;
aliases = (CollAliasData *) palloc(maxaliases * sizeof(CollAliasData));
naliases = 0;
locale_a_handle = OpenPipeStream("locale -a", "r");
if (locale_a_handle == NULL)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not execute command \"%s\": %m",
"locale -a")));
while (fgets(localebuf, sizeof(localebuf), locale_a_handle))
{
size_t len;
int enc;
char alias[NAMEDATALEN];
len = strlen(localebuf);
if (len == 0 || localebuf[len - 1] != '\n')
{
elog(DEBUG1, "locale name too long, skipped: \"%s\"", localebuf);
continue;
}
localebuf[len - 1] = '\0';
/*
* Some systems have locale names that don't consist entirely of
* ASCII letters (such as "bokmål" or "français").
* This is pretty silly, since we need the locale itself to
* interpret the non-ASCII characters. We can't do much with
* those, so we filter them out.
*/
if (!is_all_ascii(localebuf))
{
elog(DEBUG1, "locale name has non-ASCII characters, skipped: \"%s\"", localebuf);
continue;
}
enc = pg_get_encoding_from_locale(localebuf, false);
if (enc < 0)
{
/* error message printed by pg_get_encoding_from_locale() */
continue;
}
if (!PG_VALID_BE_ENCODING(enc))
continue; /* ignore locales for client-only encodings */
if (enc == PG_SQL_ASCII)
continue; /* C/POSIX are already in the catalog */
/* count valid locales found in operating system */
nvalid++;
/*
* Create a collation named the same as the locale, but quietly
* doing nothing if it already exists. This is the behavior we
* need even at initdb time, because some versions of "locale -a"
* can report the same locale name more than once. And it's
* convenient for later import runs, too, since you just about
* always want to add on new locales without a lot of chatter
* about existing ones.
*/
collid = CollationCreate(localebuf, nspid, GetUserId(),
COLLPROVIDER_LIBC, true, enc,
localebuf, localebuf,
get_collation_actual_version(COLLPROVIDER_LIBC, localebuf),
true, true);
if (OidIsValid(collid))
{
ncreated++;
/* Must do CCI between inserts to handle duplicates correctly */
CommandCounterIncrement();
}
/*
* Generate aliases such as "en_US" in addition to "en_US.utf8"
* for ease of use. Note that collation names are unique per
* encoding only, so this doesn't clash with "en_US" for LATIN1,
* say.
*
* However, it might conflict with a name we'll see later in the
* "locale -a" output. So save up the aliases and try to add them
* after we've read all the output.
*/
if (normalize_libc_locale_name(alias, localebuf))
{
if (naliases >= maxaliases)
{
maxaliases *= 2;
aliases = (CollAliasData *)
repalloc(aliases, maxaliases * sizeof(CollAliasData));
}
aliases[naliases].localename = pstrdup(localebuf);
aliases[naliases].alias = pstrdup(alias);
aliases[naliases].enc = enc;
naliases++;
}
}
ClosePipeStream(locale_a_handle);
/*
* Before processing the aliases, sort them by locale name. The point
* here is that if "locale -a" gives us multiple locale names with the
* same encoding and base name, say "en_US.utf8" and "en_US.utf-8", we
* want to pick a deterministic one of them. First in ASCII sort
* order is a good enough rule. (Before PG 10, the code corresponding
* to this logic in initdb.c had an additional ordering rule, to
* prefer the locale name exactly matching the alias, if any. We
* don't need to consider that here, because we would have already
* created such a pg_collation entry above, and that one will win.)
*/
if (naliases > 1)
qsort((void *) aliases, naliases, sizeof(CollAliasData), cmpaliases);
/* Now add aliases, ignoring any that match pre-existing entries */
for (i = 0; i < naliases; i++)
{
char *locale = aliases[i].localename;
char *alias = aliases[i].alias;
int enc = aliases[i].enc;
collid = CollationCreate(alias, nspid, GetUserId(),
COLLPROVIDER_LIBC, true, enc,
locale, locale,
get_collation_actual_version(COLLPROVIDER_LIBC, locale),
true, true);
if (OidIsValid(collid))
{
ncreated++;
CommandCounterIncrement();
}
}
/* Give a warning if "locale -a" seems to be malfunctioning */
if (nvalid == 0)
ereport(WARNING,
(errmsg("no usable system locales were found")));
}
#endif /* READ_LOCALE_A_OUTPUT */
/*
* Load collations known to ICU
*
* We use uloc_countAvailable()/uloc_getAvailable() rather than
* ucol_countAvailable()/ucol_getAvailable(). The former returns a full
* set of language+region combinations, whereas the latter only returns
* language+region combinations of they are distinct from the language's
* base collation. So there might not be a de-DE or en-GB, which would be
* confusing.
*/
#ifdef USE_ICU
{
int i;
/*
* Start the loop at -1 to sneak in the root locale without too much
* code duplication.
*/
for (i = -1; i < uloc_countAvailable(); i++)
{
const char *name;
char *langtag;
char *icucomment;
const char *collcollate;
Oid collid;
if (i == -1)
name = ""; /* ICU root locale */
else
name = uloc_getAvailable(i);
langtag = get_icu_language_tag(name);
collcollate = U_ICU_VERSION_MAJOR_NUM >= 54 ? langtag : name;
/*
* Be paranoid about not allowing any non-ASCII strings into
* pg_collation
*/
if (!is_all_ascii(langtag) || !is_all_ascii(collcollate))
continue;
collid = CollationCreate(psprintf("%s-x-icu", langtag),
nspid, GetUserId(),
COLLPROVIDER_ICU, true, -1,
collcollate, collcollate,
get_collation_actual_version(COLLPROVIDER_ICU, collcollate),
true, true);
if (OidIsValid(collid))
{
ncreated++;
CommandCounterIncrement();
icucomment = get_icu_locale_comment(name);
if (icucomment)
CreateComments(collid, CollationRelationId, 0,
icucomment);
}
}
}
#endif /* USE_ICU */
PG_RETURN_INT32(ncreated);
}