database/postgres
database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-04-24 10:47:04 +03:00
Code
postgres/src/backend/commands/proclang.c
Tom Lane 039dfbfd5d Reduce the need for frontend programs to include "postgres.h" by refactoring 
inclusions in src/include/catalog/*.h files.  The main idea here is to push
function declarations for src/backend/catalog/*.c files into separate headers,
rather than sticking them into the corresponding catalog definition file as
has been done in the past.  This commit only carries out that idea fully for
pg_proc, pg_type and pg_conversion, but that's enough for the moment ---
if pg_list.h ever becomes unsafe for frontend code to include, we'll need
to work a bit more.

Zdenek Kotala
2008-03-27 03:57:34 +00:00

606 lines
16 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* proclang.c
* PostgreSQL PROCEDURAL LANGUAGE support code.
*
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/proclang.c,v 1.77 2008/03/27 03:57:33 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/pg_authid.h"
#include "catalog/pg_language.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_pltemplate.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_proc_fn.h"
#include "catalog/pg_type.h"
#include "commands/dbcommands.h"
#include "commands/defrem.h"
#include "commands/proclang.h"
#include "miscadmin.h"
#include "parser/gramparse.h"
#include "parser/parse_func.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
#include "utils/tqual.h"
typedef struct
{
bool tmpltrusted; /* trusted? */
bool tmpldbacreate; /* db owner allowed to create? */
char *tmplhandler; /* name of handler function */
char *tmplvalidator; /* name of validator function, or NULL */
char *tmpllibrary; /* path of shared library */
} PLTemplate;
static void create_proc_lang(const char *languageName,
Oid languageOwner, Oid handlerOid, Oid valOid, bool trusted);
static PLTemplate *find_language_template(const char *languageName);
/* ---------------------------------------------------------------------
* CREATE PROCEDURAL LANGUAGE
* ---------------------------------------------------------------------
*/
void
CreateProceduralLanguage(CreatePLangStmt *stmt)
{
char *languageName;
PLTemplate *pltemplate;
Oid handlerOid,
valOid;
Oid funcrettype;
Oid funcargtypes[1];
/*
* Translate the language name and check that this language doesn't
* already exist
*/
languageName = case_translate_language_name(stmt->plname);
if (SearchSysCacheExists(LANGNAME,
PointerGetDatum(languageName),
0, 0, 0))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("language \"%s\" already exists", languageName)));
/*
* If we have template information for the language, ignore the supplied
* parameters (if any) and use the template information.
*/
if ((pltemplate = find_language_template(languageName)) != NULL)
{
List *funcname;
/*
* Give a notice if we are ignoring supplied parameters.
*/
if (stmt->plhandler)
ereport(NOTICE,
(errmsg("using pg_pltemplate information instead of CREATE LANGUAGE parameters")));
/*
* Check permission
*/
if (!superuser())
{
if (!pltemplate->tmpldbacreate)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("must be superuser to create procedural language \"%s\"",
languageName)));
if (!pg_database_ownercheck(MyDatabaseId, GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_DATABASE,
get_database_name(MyDatabaseId));
}
/*
* Find or create the handler function, which we force to be in the
* pg_catalog schema. If already present, it must have the correct
* return type.
*/
funcname = SystemFuncName(pltemplate->tmplhandler);
handlerOid = LookupFuncName(funcname, 0, funcargtypes, true);
if (OidIsValid(handlerOid))
{
funcrettype = get_func_rettype(handlerOid);
if (funcrettype != LANGUAGE_HANDLEROID)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("function %s must return type \"language_handler\"",
NameListToString(funcname))));
}
else
{
handlerOid = ProcedureCreate(pltemplate->tmplhandler,
PG_CATALOG_NAMESPACE,
false, /* replace */
false, /* returnsSet */
LANGUAGE_HANDLEROID,
ClanguageId,
F_FMGR_C_VALIDATOR,
pltemplate->tmplhandler,
pltemplate->tmpllibrary,
false, /* isAgg */
false, /* security_definer */
false, /* isStrict */
PROVOLATILE_VOLATILE,
buildoidvector(funcargtypes, 0),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
1,
0);
}
/*
* Likewise for the validator, if required; but we don't care about
* its return type.
*/
if (pltemplate->tmplvalidator)
{
funcname = SystemFuncName(pltemplate->tmplvalidator);
funcargtypes[0] = OIDOID;
valOid = LookupFuncName(funcname, 1, funcargtypes, true);
if (!OidIsValid(valOid))
{
valOid = ProcedureCreate(pltemplate->tmplvalidator,
PG_CATALOG_NAMESPACE,
false, /* replace */
false, /* returnsSet */
VOIDOID,
ClanguageId,
F_FMGR_C_VALIDATOR,
pltemplate->tmplvalidator,
pltemplate->tmpllibrary,
false, /* isAgg */
false, /* security_definer */
false, /* isStrict */
PROVOLATILE_VOLATILE,
buildoidvector(funcargtypes, 1),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
PointerGetDatum(NULL),
1,
0);
}
}
else
valOid = InvalidOid;
/* ok, create it */
create_proc_lang(languageName, GetUserId(), handlerOid, valOid,
pltemplate->tmpltrusted);
}
else
{
/*
* No template, so use the provided information. If there's no
* handler clause, the user is trying to rely on a template that we
* don't have, so complain accordingly.
*/
if (!stmt->plhandler)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("unsupported language \"%s\"",
languageName),
errhint("The supported languages are listed in the pg_pltemplate system catalog.")));
/*
* Check permission
*/
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("must be superuser to create custom procedural language")));
/*
* Lookup the PL handler function and check that it is of the expected
* return type
*/
handlerOid = LookupFuncName(stmt->plhandler, 0, funcargtypes, false);
funcrettype = get_func_rettype(handlerOid);
if (funcrettype != LANGUAGE_HANDLEROID)
{
/*
* We allow OPAQUE just so we can load old dump files. When we
* see a handler function declared OPAQUE, change it to
* LANGUAGE_HANDLER. (This is probably obsolete and removable?)
*/
if (funcrettype == OPAQUEOID)
{
ereport(WARNING,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("changing return type of function %s from \"opaque\" to \"language_handler\"",
NameListToString(stmt->plhandler))));
SetFunctionReturnType(handlerOid, LANGUAGE_HANDLEROID);
}
else
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("function %s must return type \"language_handler\"",
NameListToString(stmt->plhandler))));
}
/* validate the validator function */
if (stmt->plvalidator)
{
funcargtypes[0] = OIDOID;
valOid = LookupFuncName(stmt->plvalidator, 1, funcargtypes, false);
/* return value is ignored, so we don't check the type */
}
else
valOid = InvalidOid;
/* ok, create it */
create_proc_lang(languageName, GetUserId(), handlerOid, valOid,
stmt->pltrusted);
}
}
/*
* Guts of language creation.
*/
static void
create_proc_lang(const char *languageName,
Oid languageOwner, Oid handlerOid, Oid valOid, bool trusted)
{
Relation rel;
TupleDesc tupDesc;
Datum values[Natts_pg_language];
char nulls[Natts_pg_language];
NameData langname;
HeapTuple tup;
ObjectAddress myself,
referenced;
/*
* Insert the new language into pg_language
*/
rel = heap_open(LanguageRelationId, RowExclusiveLock);
tupDesc = rel->rd_att;
memset(values, 0, sizeof(values));
memset(nulls, ' ', sizeof(nulls));
namestrcpy(&langname, languageName);
values[Anum_pg_language_lanname - 1] = NameGetDatum(&langname);
values[Anum_pg_language_lanowner - 1] = ObjectIdGetDatum(languageOwner);
values[Anum_pg_language_lanispl - 1] = BoolGetDatum(true);
values[Anum_pg_language_lanpltrusted - 1] = BoolGetDatum(trusted);
values[Anum_pg_language_lanplcallfoid - 1] = ObjectIdGetDatum(handlerOid);
values[Anum_pg_language_lanvalidator - 1] = ObjectIdGetDatum(valOid);
nulls[Anum_pg_language_lanacl - 1] = 'n';
tup = heap_formtuple(tupDesc, values, nulls);
simple_heap_insert(rel, tup);
CatalogUpdateIndexes(rel, tup);
/*
* Create dependencies for language
*/
myself.classId = LanguageRelationId;
myself.objectId = HeapTupleGetOid(tup);
myself.objectSubId = 0;
/* dependency on owner of language */
referenced.classId = AuthIdRelationId;
referenced.objectId = languageOwner;
referenced.objectSubId = 0;
recordSharedDependencyOn(&myself, &referenced, SHARED_DEPENDENCY_OWNER);
/* dependency on the PL handler function */
referenced.classId = ProcedureRelationId;
referenced.objectId = handlerOid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* dependency on the validator function, if any */
if (OidIsValid(valOid))
{
referenced.classId = ProcedureRelationId;
referenced.objectId = valOid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
heap_close(rel, RowExclusiveLock);
}
/*
* Look to see if we have template information for the given language name.
*/
static PLTemplate *
find_language_template(const char *languageName)
{
PLTemplate *result;
Relation rel;
SysScanDesc scan;
ScanKeyData key;
HeapTuple tup;
rel = heap_open(PLTemplateRelationId, AccessShareLock);
ScanKeyInit(&key,
Anum_pg_pltemplate_tmplname,
BTEqualStrategyNumber, F_NAMEEQ,
NameGetDatum(languageName));
scan = systable_beginscan(rel, PLTemplateNameIndexId, true,
SnapshotNow, 1, &key);
tup = systable_getnext(scan);
if (HeapTupleIsValid(tup))
{
Form_pg_pltemplate tmpl = (Form_pg_pltemplate) GETSTRUCT(tup);
Datum datum;
bool isnull;
result = (PLTemplate *) palloc0(sizeof(PLTemplate));
result->tmpltrusted = tmpl->tmpltrusted;
result->tmpldbacreate = tmpl->tmpldbacreate;
/* Remaining fields are variable-width so we need heap_getattr */
datum = heap_getattr(tup, Anum_pg_pltemplate_tmplhandler,
RelationGetDescr(rel), &isnull);
if (!isnull)
result->tmplhandler = TextDatumGetCString(datum);
datum = heap_getattr(tup, Anum_pg_pltemplate_tmplvalidator,
RelationGetDescr(rel), &isnull);
if (!isnull)
result->tmplvalidator = TextDatumGetCString(datum);
datum = heap_getattr(tup, Anum_pg_pltemplate_tmpllibrary,
RelationGetDescr(rel), &isnull);
if (!isnull)
result->tmpllibrary = TextDatumGetCString(datum);
/* Ignore template if handler or library info is missing */
if (!result->tmplhandler || !result->tmpllibrary)
result = NULL;
}
else
result = NULL;
systable_endscan(scan);
heap_close(rel, AccessShareLock);
return result;
}
/*
* This just returns TRUE if we have a valid template for a given language
*/
bool
PLTemplateExists(const char *languageName)
{
return (find_language_template(languageName) != NULL);
}
/* ---------------------------------------------------------------------
* DROP PROCEDURAL LANGUAGE
* ---------------------------------------------------------------------
*/
void
DropProceduralLanguage(DropPLangStmt *stmt)
{
char *languageName;
HeapTuple langTup;
ObjectAddress object;
/*
* Translate the language name, check that the language exists
*/
languageName = case_translate_language_name(stmt->plname);
langTup = SearchSysCache(LANGNAME,
CStringGetDatum(languageName),
0, 0, 0);
if (!HeapTupleIsValid(langTup))
{
if (!stmt->missing_ok)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("language \"%s\" does not exist", languageName)));
else
ereport(NOTICE,
(errmsg("language \"%s\" does not exist, skipping",
languageName)));
return;
}
/*
* Check permission
*/
if (!pg_language_ownercheck(HeapTupleGetOid(langTup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_LANGUAGE,
languageName);
object.classId = LanguageRelationId;
object.objectId = HeapTupleGetOid(langTup);
object.objectSubId = 0;
ReleaseSysCache(langTup);
/*
* Do the deletion
*/
performDeletion(&object, stmt->behavior);
}
/*
* Guts of language dropping.
*/
void
DropProceduralLanguageById(Oid langOid)
{
Relation rel;
HeapTuple langTup;
rel = heap_open(LanguageRelationId, RowExclusiveLock);
langTup = SearchSysCache(LANGOID,
ObjectIdGetDatum(langOid),
0, 0, 0);
if (!HeapTupleIsValid(langTup)) /* should not happen */
elog(ERROR, "cache lookup failed for language %u", langOid);
simple_heap_delete(rel, &langTup->t_self);
ReleaseSysCache(langTup);
heap_close(rel, RowExclusiveLock);
}
/*
* Rename language
*/
void
RenameLanguage(const char *oldname, const char *newname)
{
HeapTuple tup;
Relation rel;
/* Translate both names for consistency with CREATE */
oldname = case_translate_language_name(oldname);
newname = case_translate_language_name(newname);
rel = heap_open(LanguageRelationId, RowExclusiveLock);
tup = SearchSysCacheCopy(LANGNAME,
CStringGetDatum(oldname),
0, 0, 0);
if (!HeapTupleIsValid(tup))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("language \"%s\" does not exist", oldname)));
/* make sure the new name doesn't exist */
if (SearchSysCacheExists(LANGNAME,
CStringGetDatum(newname),
0, 0, 0))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("language \"%s\" already exists", newname)));
/* must be owner of PL */
if (!pg_language_ownercheck(HeapTupleGetOid(tup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_LANGUAGE,
oldname);
/* rename */
namestrcpy(&(((Form_pg_language) GETSTRUCT(tup))->lanname), newname);
simple_heap_update(rel, &tup->t_self, tup);
CatalogUpdateIndexes(rel, tup);
heap_close(rel, NoLock);
heap_freetuple(tup);
}
/*
* Change language owner
*/
void
AlterLanguageOwner(const char *name, Oid newOwnerId)
{
HeapTuple tup;
Relation rel;
Form_pg_language lanForm;
/* Translate name for consistency with CREATE */
name = case_translate_language_name(name);
rel = heap_open(LanguageRelationId, RowExclusiveLock);
tup = SearchSysCache(LANGNAME,
CStringGetDatum(name),
0, 0, 0);
if (!HeapTupleIsValid(tup))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("language \"%s\" does not exist", name)));
lanForm = (Form_pg_language) GETSTRUCT(tup);
/*
* If the new owner is the same as the existing owner, consider the
* command to have succeeded. This is for dump restoration purposes.
*/
if (lanForm->lanowner != newOwnerId)
{
Datum repl_val[Natts_pg_language];
char repl_null[Natts_pg_language];
char repl_repl[Natts_pg_language];
Acl *newAcl;
Datum aclDatum;
bool isNull;
HeapTuple newtuple;
/* Otherwise, must be owner of the existing object */
if (!pg_language_ownercheck(HeapTupleGetOid(tup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_LANGUAGE,
NameStr(lanForm->lanname));
/* Must be able to become new owner */
check_is_member_of_role(GetUserId(), newOwnerId);
memset(repl_null, ' ', sizeof(repl_null));
memset(repl_repl, ' ', sizeof(repl_repl));
repl_repl[Anum_pg_language_lanowner - 1] = 'r';
repl_val[Anum_pg_language_lanowner - 1] = ObjectIdGetDatum(newOwnerId);
/*
* Determine the modified ACL for the new owner. This is only
* necessary when the ACL is non-null.
*/
aclDatum = SysCacheGetAttr(LANGNAME, tup,
Anum_pg_language_lanacl,
&isNull);
if (!isNull)
{
newAcl = aclnewowner(DatumGetAclP(aclDatum),
lanForm->lanowner, newOwnerId);
repl_repl[Anum_pg_language_lanacl - 1] = 'r';
repl_val[Anum_pg_language_lanacl - 1] = PointerGetDatum(newAcl);
}
newtuple = heap_modifytuple(tup, RelationGetDescr(rel),
repl_val, repl_null, repl_repl);
simple_heap_update(rel, &newtuple->t_self, newtuple);
CatalogUpdateIndexes(rel, newtuple);
heap_freetuple(newtuple);
/* Update owner dependency reference */
changeDependencyOnOwner(LanguageRelationId, HeapTupleGetOid(tup),
newOwnerId);
}
ReleaseSysCache(tup);
heap_close(rel, RowExclusiveLock);
}
View Git Blame Copy Permalink