citus/src/backend/distributed/deparser/deparse_function_stmts.c

613 lines
15 KiB
C

/*-------------------------------------------------------------------------
*
* deparse_function_stmts.c
*
* All routines to deparse function and procedure statements.
* This file contains all entry points specific for function and procedure statement
* deparsing
*
* Functions that could move later are AppendDefElem, AppendDefElemStrict, etc. These
* should be reused across multiple statements and should live in their own deparse
* file.
*
* Copyright (c), Citus Data, Inc.
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/htup_details.h"
#include "catalog/namespace.h"
#include "catalog/pg_proc.h"
#include "commands/defrem.h"
#include "distributed/citus_ruleutils.h"
#include "distributed/commands.h"
#include "distributed/deparser.h"
#include "distributed/version_compat.h"
#include "lib/stringinfo.h"
#include "nodes/makefuncs.h"
#include "nodes/nodes.h"
#include "nodes/value.h"
#include "parser/parse_func.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/fmgrprotos.h"
#include "utils/guc.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/syscache.h"
/* forward declaration for deparse functions */
static const char * ObjectTypeToKeyword(ObjectType objtype);
static void AppendAlterFunctionStmt(StringInfo buf, AlterFunctionStmt *stmt);
static void AppendDropFunctionStmt(StringInfo buf, DropStmt *stmt);
static void AppendFunctionName(StringInfo buf, ObjectWithArgs *func, ObjectType objtype);
static void AppendFunctionNameList(StringInfo buf, List *objects, ObjectType objtype);
static void AppendDefElem(StringInfo buf, DefElem *def);
static void AppendDefElemStrict(StringInfo buf, DefElem *def);
static void AppendDefElemVolatility(StringInfo buf, DefElem *def);
static void AppendDefElemLeakproof(StringInfo buf, DefElem *def);
static void AppendDefElemSecurity(StringInfo buf, DefElem *def);
static void AppendDefElemParallel(StringInfo buf, DefElem *def);
static void AppendDefElemCost(StringInfo buf, DefElem *def);
static void AppendDefElemRows(StringInfo buf, DefElem *def);
static void AppendDefElemSet(StringInfo buf, DefElem *def);
static void AppendRenameFunctionStmt(StringInfo buf, RenameStmt *stmt);
static void AppendAlterFunctionSchemaStmt(StringInfo buf, AlterObjectSchemaStmt *stmt);
static void AppendAlterFunctionOwnerStmt(StringInfo buf, AlterOwnerStmt *stmt);
static void AppendAlterFunctionDependsStmt(StringInfo buf, AlterObjectDependsStmt *stmt);
static char * CopyAndConvertToUpperCase(const char *str);
/*
* DeparseAlterFunctionStmt builds and returns a string representing the AlterFunctionStmt
*/
const char *
DeparseAlterFunctionStmt(AlterFunctionStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AppendAlterFunctionStmt(&str, stmt);
return str.data;
}
/*
* ObjectTypeToKeyword returns an appropriate string for the given ObjectType
* Where the string will be one of "FUNCTION", "PROCEDURE", or "AGGREGATE"
*/
static const char *
ObjectTypeToKeyword(ObjectType objtype)
{
switch (objtype)
{
case OBJECT_FUNCTION:
{
return "FUNCTION";
}
case OBJECT_PROCEDURE:
{
return "PROCEDURE";
}
case OBJECT_AGGREGATE:
{
return "AGGREGATE";
}
default:
elog(ERROR, "Unknown object type: %d", objtype);
return NULL;
}
}
/*
* AppendAlterFunctionStmt appends a string representing the AlterFunctionStmt to a buffer
*/
static void
AppendAlterFunctionStmt(StringInfo buf, AlterFunctionStmt *stmt)
{
ListCell *actionCell = NULL;
appendStringInfo(buf, "ALTER %s ", ObjectTypeToKeyword(stmt->objtype));
AppendFunctionName(buf, stmt->func, stmt->objtype);
foreach(actionCell, stmt->actions)
{
DefElem *def = castNode(DefElem, lfirst(actionCell));
AppendDefElem(buf, def);
}
appendStringInfoString(buf, ";");
}
/*
* AppendDefElem appends a string representing the DefElem to a buffer
*/
static void
AppendDefElem(StringInfo buf, DefElem *def)
{
if (strcmp(def->defname, "strict") == 0)
{
AppendDefElemStrict(buf, def);
}
else if (strcmp(def->defname, "volatility") == 0)
{
AppendDefElemVolatility(buf, def);
}
else if (strcmp(def->defname, "leakproof") == 0)
{
AppendDefElemLeakproof(buf, def);
}
else if (strcmp(def->defname, "security") == 0)
{
AppendDefElemSecurity(buf, def);
}
else if (strcmp(def->defname, "parallel") == 0)
{
AppendDefElemParallel(buf, def);
}
else if (strcmp(def->defname, "cost") == 0)
{
AppendDefElemCost(buf, def);
}
else if (strcmp(def->defname, "rows") == 0)
{
AppendDefElemRows(buf, def);
}
else if (strcmp(def->defname, "set") == 0)
{
AppendDefElemSet(buf, def);
}
}
/*
* AppendDefElemStrict appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemStrict(StringInfo buf, DefElem *def)
{
if (intVal(def->arg) == 1)
{
appendStringInfo(buf, " STRICT");
}
else
{
appendStringInfo(buf, " CALLED ON NULL INPUT");
}
}
/*
* AppendDefElemVolatility appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemVolatility(StringInfo buf, DefElem *def)
{
appendStringInfo(buf, " %s", CopyAndConvertToUpperCase(strVal(def->arg)));
}
/*
* AppendDefElemLeakproof appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemLeakproof(StringInfo buf, DefElem *def)
{
if (intVal(def->arg) == 0)
{
appendStringInfo(buf, " NOT");
}
appendStringInfo(buf, " LEAKPROOF");
}
/*
* AppendDefElemSecurity appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemSecurity(StringInfo buf, DefElem *def)
{
if (intVal(def->arg) == 0)
{
appendStringInfo(buf, " SECURITY INVOKER");
}
else
{
appendStringInfo(buf, " SECURITY DEFINER");
}
}
/*
* AppendDefElemParallel appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemParallel(StringInfo buf, DefElem *def)
{
appendStringInfo(buf, " PARALLEL %s", CopyAndConvertToUpperCase(strVal(def->arg)));
}
/*
* AppendDefElemCost appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemCost(StringInfo buf, DefElem *def)
{
appendStringInfo(buf, " COST %lf", defGetNumeric(def));
}
/*
* AppendDefElemRows appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemRows(StringInfo buf, DefElem *def)
{
appendStringInfo(buf, " ROWS %lf", defGetNumeric(def));
}
/*
* AppendDefElemSet appends a string representing the DefElem to a buffer
*/
static void
AppendDefElemSet(StringInfo buf, DefElem *def)
{
VariableSetStmt *setStmt = castNode(VariableSetStmt, def->arg);
char *setVariableArgs = ExtractSetVariableArgs(setStmt);
switch (setStmt->kind)
{
case VAR_SET_VALUE:
{
appendStringInfo(buf, " SET %s = %s", setStmt->name, setVariableArgs);
break;
}
case VAR_SET_CURRENT:
{
appendStringInfo(buf, " SET %s FROM CURRENT", setStmt->name);
break;
}
case VAR_SET_DEFAULT:
{
appendStringInfo(buf, " SET %s TO DEFAULT", setStmt->name);
break;
}
case VAR_RESET:
{
appendStringInfo(buf, " RESET %s", setStmt->name);
break;
}
case VAR_RESET_ALL:
{
appendStringInfoString(buf, " RESET ALL");
break;
}
/* VAR_SET_MULTI is a special case for SET TRANSACTION that should not occur here */
case VAR_SET_MULTI:
default:
{
ereport(ERROR, (errmsg("Unable to deparse SET statement")));
break;
}
}
}
/*
* DeparseRenameFunctionStmt builds and returns a string representing the RenameStmt
*/
const char *
DeparseRenameFunctionStmt(RenameStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AssertObjectTypeIsFunctional(stmt->renameType);
AppendRenameFunctionStmt(&str, stmt);
return str.data;
}
/*
* AppendRenameFunctionStmt appends a string representing the RenameStmt to a buffer
*/
static void
AppendRenameFunctionStmt(StringInfo buf, RenameStmt *stmt)
{
ObjectWithArgs *func = castNode(ObjectWithArgs, stmt->object);
appendStringInfo(buf, "ALTER %s ", ObjectTypeToKeyword(stmt->renameType));
AppendFunctionName(buf, func, stmt->renameType);
appendStringInfo(buf, " RENAME TO %s;", quote_identifier(stmt->newname));
}
/*
* DeparseAlterFunctionSchemaStmt builds and returns a string representing the AlterObjectSchemaStmt
*/
const char *
DeparseAlterFunctionSchemaStmt(AlterObjectSchemaStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AssertObjectTypeIsFunctional(stmt->objectType);
AppendAlterFunctionSchemaStmt(&str, stmt);
return str.data;
}
/*
* AppendAlterFunctionSchemaStmt appends a string representing the AlterObjectSchemaStmt to a buffer
*/
static void
AppendAlterFunctionSchemaStmt(StringInfo buf, AlterObjectSchemaStmt *stmt)
{
ObjectWithArgs *func = castNode(ObjectWithArgs, stmt->object);
appendStringInfo(buf, "ALTER %s ", ObjectTypeToKeyword(stmt->objectType));
AppendFunctionName(buf, func, stmt->objectType);
appendStringInfo(buf, " SET SCHEMA %s;", quote_identifier(stmt->newschema));
}
/*
* DeparseAlterFunctionOwnerStmt builds and returns a string representing the AlterOwnerStmt
*/
const char *
DeparseAlterFunctionOwnerStmt(AlterOwnerStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AssertObjectTypeIsFunctional(stmt->objectType);
AppendAlterFunctionOwnerStmt(&str, stmt);
return str.data;
}
/*
* AppendAlterFunctionOwnerStmt appends a string representing the AlterOwnerStmt to a buffer
*/
static void
AppendAlterFunctionOwnerStmt(StringInfo buf, AlterOwnerStmt *stmt)
{
ObjectWithArgs *func = castNode(ObjectWithArgs, stmt->object);
appendStringInfo(buf, "ALTER %s ", ObjectTypeToKeyword(stmt->objectType));
AppendFunctionName(buf, func, stmt->objectType);
appendStringInfo(buf, " OWNER TO %s;", RoleSpecString(stmt->newowner, true));
}
/*
* DeparseAlterFunctionDependsStmt builds and returns a string representing the AlterObjectDependsStmt
*/
const char *
DeparseAlterFunctionDependsStmt(AlterObjectDependsStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AssertObjectTypeIsFunctional(stmt->objectType);
AppendAlterFunctionDependsStmt(&str, stmt);
return str.data;
}
/*
* AppendAlterFunctionDependsStmt appends a string representing the AlterObjectDependsStmt to a buffer
*/
static void
AppendAlterFunctionDependsStmt(StringInfo buf, AlterObjectDependsStmt *stmt)
{
ObjectWithArgs *func = castNode(ObjectWithArgs, stmt->object);
appendStringInfo(buf, "ALTER %s ", ObjectTypeToKeyword(stmt->objectType));
AppendFunctionName(buf, func, stmt->objectType);
appendStringInfo(buf, " DEPENDS ON EXTENSION %s;", strVal(stmt->extname));
}
/*
* DeparseDropFunctionStmt builds and returns a string representing the DropStmt
*/
const char *
DeparseDropFunctionStmt(DropStmt *stmt)
{
StringInfoData str = { 0 };
initStringInfo(&str);
AssertObjectTypeIsFunctional(stmt->removeType);
AppendDropFunctionStmt(&str, stmt);
return str.data;
}
/*
* AppendDropFunctionStmt appends a string representing the DropStmt to a buffer
*/
static void
AppendDropFunctionStmt(StringInfo buf, DropStmt *stmt)
{
appendStringInfo(buf, "DROP %s ", ObjectTypeToKeyword(stmt->removeType));
if (stmt->missing_ok)
{
appendStringInfoString(buf, "IF EXISTS ");
}
AppendFunctionNameList(buf, stmt->objects, stmt->removeType);
if (stmt->behavior == DROP_CASCADE)
{
appendStringInfoString(buf, " CASCADE");
}
appendStringInfoString(buf, ";");
}
/*
* AppendFunctionNameList appends a string representing the list of function names to a buffer
*/
static void
AppendFunctionNameList(StringInfo buf, List *objects, ObjectType objtype)
{
ListCell *objectCell = NULL;
foreach(objectCell, objects)
{
Node *object = lfirst(objectCell);
ObjectWithArgs *func = NULL;
if (objectCell != list_head(objects))
{
appendStringInfo(buf, ", ");
}
func = castNode(ObjectWithArgs, object);
AppendFunctionName(buf, func, objtype);
}
}
/*
* AppendFunctionName appends a string representing a single function name to a buffer
*/
static void
AppendFunctionName(StringInfo buf, ObjectWithArgs *func, ObjectType objtype)
{
Oid funcid = InvalidOid;
HeapTuple proctup;
char *functionName = NULL;
char *schemaName = NULL;
char *qualifiedFunctionName;
funcid = LookupFuncWithArgs(objtype, func, true);
proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
if (!HeapTupleIsValid(proctup))
{
/*
* DROP FUNCTION IF EXISTS absent_function arrives here
*
* There is no namespace associated with the nonexistent function,
* thus we return the function name as it is provided
*/
DeconstructQualifiedName(func->objname, &schemaName, &functionName);
}
else
{
Form_pg_proc procform;
procform = (Form_pg_proc) GETSTRUCT(proctup);
functionName = NameStr(procform->proname);
functionName = pstrdup(functionName); /* we release the tuple before used */
schemaName = get_namespace_name(procform->pronamespace);
ReleaseSysCache(proctup);
}
qualifiedFunctionName = quote_qualified_identifier(schemaName, functionName);
appendStringInfoString(buf, qualifiedFunctionName);
if (OidIsValid(funcid))
{
/*
* If the function exists we want to use pg_get_function_identity_arguments to
* serialize its canonical arguments
*/
OverrideSearchPath *overridePath = NULL;
Datum sqlTextDatum = 0;
const char *args = NULL;
/*
* Set search_path to NIL so that all objects outside of pg_catalog will be
* schema-prefixed. pg_catalog will be added automatically when we call
* PushOverrideSearchPath(), since we set addCatalog to true;
*/
overridePath = GetOverrideSearchPath(CurrentMemoryContext);
overridePath->schemas = NIL;
overridePath->addCatalog = true;
PushOverrideSearchPath(overridePath);
sqlTextDatum = DirectFunctionCall1(pg_get_function_identity_arguments,
ObjectIdGetDatum(funcid));
/* revert back to original search_path */
PopOverrideSearchPath();
args = TextDatumGetCString(sqlTextDatum);
appendStringInfo(buf, "(%s)", args);
}
else if (!func->args_unspecified)
{
/*
* The function is not found, but there is an argument list specified, this has
* some known issues with the "any" type. However this is mostly a bug in
* postgres' TypeNameListToString. For now the best we can do until we understand
* the underlying cause better.
*/
const char *args = NULL;
args = TypeNameListToString(func->objargs);
appendStringInfo(buf, "(%s)", args);
}
/*
* If the type is not found, and no argument list given we don't append anything here.
* This will cause mostly the same sql as the original statement.
*/
}
/*
* CopyAndConvertToUpperCase copies a string and converts all characters to uppercase
*/
static char *
CopyAndConvertToUpperCase(const char *str)
{
char *result, *p;
result = pstrdup(str);
for (p = result; *p; p++)
{
*p = pg_toupper((unsigned char) *p);
}
return result;
}