greenplumn pl_comp 源码
greenplumn pl_comp 代码
文件路径：/src/pl/plpgsql/src/pl_comp.c
/*-------------------------------------------------------------------------
*
* pl_comp.c - Compiler part of the PL/pgSQL
* procedural language
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/pl/plpgsql/src/pl_comp.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <ctype.h>
#include "access/htup_details.h"
#include "catalog/namespace.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "nodes/makefuncs.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/regproc.h"
#include "utils/rel.h"
#include "utils/syscache.h"
#include "utils/typcache.h"
#include "plpgsql.h"
/* ----------
* Our own local and global variables
* ----------
*/
PLpgSQL_stmt_block *plpgsql_parse_result;
static int datums_alloc;
int plpgsql_nDatums;
PLpgSQL_datum **plpgsql_Datums;
static int datums_last;
char *plpgsql_error_funcname;
bool plpgsql_DumpExecTree = false;
bool plpgsql_check_syntax = false;
PLpgSQL_function *plpgsql_curr_compile;
/* A context appropriate for short-term allocs during compilation */
MemoryContext plpgsql_compile_tmp_cxt;
/* ----------
* Hash table for compiled functions
* ----------
*/
static HTAB *plpgsql_HashTable = NULL;
typedef struct plpgsql_hashent
{
PLpgSQL_func_hashkey key;
PLpgSQL_function *function;
} plpgsql_HashEnt;
#define FUNCS_PER_USER 128 /* initial table size */
/* ----------
* Lookup table for EXCEPTION condition names
* ----------
*/
typedef struct
{
const char *label;
int sqlerrstate;
} ExceptionLabelMap;
static const ExceptionLabelMap exception_label_map[] = {
#include "plerrcodes.h" /* pgrminclude ignore */
{NULL, 0}
};
/* ----------
* static prototypes
* ----------
*/
static PLpgSQL_function *do_compile(FunctionCallInfo fcinfo,
HeapTuple procTup,
PLpgSQL_function *function,
PLpgSQL_func_hashkey *hashkey,
bool forValidator);
static void plpgsql_compile_error_callback(void *arg);
static void add_parameter_name(PLpgSQL_nsitem_type itemtype, int itemno, const char *name);
static void add_dummy_return(PLpgSQL_function *function);
static Node *plpgsql_pre_column_ref(ParseState *pstate, ColumnRef *cref);
static Node *plpgsql_post_column_ref(ParseState *pstate, ColumnRef *cref, Node *var);
static Node *plpgsql_param_ref(ParseState *pstate, ParamRef *pref);
static Node *resolve_column_ref(ParseState *pstate, PLpgSQL_expr *expr,
ColumnRef *cref, bool error_if_no_field);
static Node *make_datum_param(PLpgSQL_expr *expr, int dno, int location);
static PLpgSQL_row *build_row_from_vars(PLpgSQL_variable **vars, int numvars);
static PLpgSQL_type *build_datatype(HeapTuple typeTup, int32 typmod, Oid collation);
static void plpgsql_start_datums(void);
static void plpgsql_finish_datums(PLpgSQL_function *function);
static void compute_function_hashkey(FunctionCallInfo fcinfo,
Form_pg_proc procStruct,
PLpgSQL_func_hashkey *hashkey,
bool forValidator);
static void plpgsql_resolve_polymorphic_argtypes(int numargs,
Oid *argtypes, char *argmodes,
Node *call_expr, bool forValidator,
const char *proname);
static PLpgSQL_function *plpgsql_HashTableLookup(PLpgSQL_func_hashkey *func_key);
static void plpgsql_HashTableInsert(PLpgSQL_function *function,
PLpgSQL_func_hashkey *func_key);
static void plpgsql_HashTableDelete(PLpgSQL_function *function);
static void delete_function(PLpgSQL_function *func);
/* ----------
* plpgsql_compile Make an execution tree for a PL/pgSQL function.
*
* If forValidator is true, we're only compiling for validation purposes,
* and so some checks are skipped.
*
* Note: it's important for this to fall through quickly if the function
* has already been compiled.
* ----------
*/
PLpgSQL_function *
plpgsql_compile(FunctionCallInfo fcinfo, bool forValidator)
{
Oid funcOid = fcinfo->flinfo->fn_oid;
HeapTuple procTup;
Form_pg_proc procStruct;
PLpgSQL_function *function;
PLpgSQL_func_hashkey hashkey;
bool function_valid = false;
bool hashkey_valid = false;
/*
* Lookup the pg_proc tuple by Oid; we'll need it in any case
*/
procTup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcOid));
if (!HeapTupleIsValid(procTup))
elog(ERROR, "cache lookup failed for function %u", funcOid);
procStruct = (Form_pg_proc) GETSTRUCT(procTup);
/*
* See if there's already a cache entry for the current FmgrInfo. If not,
* try to find one in the hash table.
*/
function = (PLpgSQL_function *) fcinfo->flinfo->fn_extra;
recheck:
if (!function)
{
/* Compute hashkey using function signature and actual arg types */
compute_function_hashkey(fcinfo, procStruct, &hashkey, forValidator);
hashkey_valid = true;
/* And do the lookup */
function = plpgsql_HashTableLookup(&hashkey);
}
if (function)
{
/* We have a compiled function, but is it still valid? */
if (function->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
ItemPointerEquals(&function->fn_tid, &procTup->t_self))
function_valid = true;
else
{
/*
* Nope, so remove it from hashtable and try to drop associated
* storage (if not done already).
*/
delete_function(function);
/*
* If the function isn't in active use then we can overwrite the
* func struct with new data, allowing any other existing fn_extra
* pointers to make use of the new definition on their next use.
* If it is in use then just leave it alone and make a new one.
* (The active invocations will run to completion using the
* previous definition, and then the cache entry will just be
* leaked; doesn't seem worth adding code to clean it up, given
* what a corner case this is.)
*
* If we found the function struct via fn_extra then it's possible
* a replacement has already been made, so go back and recheck the
* hashtable.
*/
if (function->use_count != 0)
{
function = NULL;
if (!hashkey_valid)
goto recheck;
}
}
}
/*
* If the function wasn't found or was out-of-date, we have to compile it
*/
if (!function_valid)
{
/*
* Calculate hashkey if we didn't already; we'll need it to store the
* completed function.
*/
if (!hashkey_valid)
compute_function_hashkey(fcinfo, procStruct, &hashkey,
forValidator);
/*
* Do the hard part.
*/
function = do_compile(fcinfo, procTup, function,
&hashkey, forValidator);
}
ReleaseSysCache(procTup);
/*
* Save pointer in FmgrInfo to avoid search on subsequent calls
*/
fcinfo->flinfo->fn_extra = (void *) function;
/*
* Finally return the compiled function
*/
return function;
}
/*
* This is the slow part of plpgsql_compile().
*
* The passed-in "function" pointer is either NULL or an already-allocated
* function struct to overwrite.
*
* While compiling a function, the CurrentMemoryContext is the
* per-function memory context of the function we are compiling. That
* means a palloc() will allocate storage with the same lifetime as
* the function itself.
*
* Because palloc()'d storage will not be immediately freed, temporary
* allocations should either be performed in a short-lived memory
* context or explicitly pfree'd. Since not all backend functions are
* careful about pfree'ing their allocations, it is also wise to
* switch into a short-term context before calling into the
* backend. An appropriate context for performing short-term
* allocations is the plpgsql_compile_tmp_cxt.
*
* NB: this code is not re-entrant. We assume that nothing we do here could
* result in the invocation of another plpgsql function.
*/
static PLpgSQL_function *
do_compile(FunctionCallInfo fcinfo,
HeapTuple procTup,
PLpgSQL_function *function,
PLpgSQL_func_hashkey *hashkey,
bool forValidator)
{
Form_pg_proc procStruct = (Form_pg_proc) GETSTRUCT(procTup);
bool is_dml_trigger = CALLED_AS_TRIGGER(fcinfo);
bool is_event_trigger = CALLED_AS_EVENT_TRIGGER(fcinfo);
Datum prosrcdatum;
bool isnull;
char *proc_source;
HeapTuple typeTup;
Form_pg_type typeStruct;
PLpgSQL_variable *var;
PLpgSQL_rec *rec;
int i;
ErrorContextCallback plerrcontext;
int parse_rc;
Oid rettypeid;
int numargs;
int num_in_args = 0;
int num_out_args = 0;
Oid *argtypes;
char **argnames;
char *argmodes;
int *in_arg_varnos = NULL;
PLpgSQL_variable **out_arg_variables;
MemoryContext func_cxt;
/*
* Setup the scanner input and error info. We assume that this function
* cannot be invoked recursively, so there's no need to save and restore
* the static variables used here.
*/
prosrcdatum = SysCacheGetAttr(PROCOID, procTup,
Anum_pg_proc_prosrc, &isnull);
if (isnull)
elog(ERROR, "null prosrc");
proc_source = TextDatumGetCString(prosrcdatum);
plpgsql_scanner_init(proc_source);
plpgsql_error_funcname = pstrdup(NameStr(procStruct->proname));
/*
* Setup error traceback support for ereport()
*/
plerrcontext.callback = plpgsql_compile_error_callback;
plerrcontext.arg = forValidator ? proc_source : NULL;
plerrcontext.previous = error_context_stack;
error_context_stack = &plerrcontext;
/*
* Do extra syntax checks when validating the function definition. We skip
* this when actually compiling functions for execution, for performance
* reasons.
*/
plpgsql_check_syntax = forValidator;
/*
* Create the new function struct, if not done already. The function
* structs are never thrown away, so keep them in TopMemoryContext.
*/
if (function == NULL)
{
function = (PLpgSQL_function *)
MemoryContextAllocZero(TopMemoryContext, sizeof(PLpgSQL_function));
}
else
{
/* re-using a previously existing struct, so clear it out */
memset(function, 0, sizeof(PLpgSQL_function));
}
plpgsql_curr_compile = function;
/*
* All the permanent output of compilation (e.g. parse tree) is kept in a
* per-function memory context, so it can be reclaimed easily.
*/
func_cxt = AllocSetContextCreate(TopMemoryContext,
"PL/pgSQL function",
ALLOCSET_DEFAULT_SIZES);
plpgsql_compile_tmp_cxt = MemoryContextSwitchTo(func_cxt);
function->fn_signature = format_procedure(fcinfo->flinfo->fn_oid);
MemoryContextSetIdentifier(func_cxt, function->fn_signature);
function->fn_oid = fcinfo->flinfo->fn_oid;
function->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
function->fn_tid = procTup->t_self;
function->fn_input_collation = fcinfo->fncollation;
function->fn_cxt = func_cxt;
function->out_param_varno = -1; /* set up for no OUT param */
function->resolve_option = plpgsql_variable_conflict;
function->print_strict_params = plpgsql_print_strict_params;
/* only promote extra warnings and errors at CREATE FUNCTION time */
function->extra_warnings = forValidator ? plpgsql_extra_warnings : 0;
function->extra_errors = forValidator ? plpgsql_extra_errors : 0;
if (is_dml_trigger)
function->fn_is_trigger = PLPGSQL_DML_TRIGGER;
else if (is_event_trigger)
function->fn_is_trigger = PLPGSQL_EVENT_TRIGGER;
else
function->fn_is_trigger = PLPGSQL_NOT_TRIGGER;
function->fn_prokind = procStruct->prokind;
function->nstatements = 0;
/*
* Initialize the compiler, particularly the namespace stack. The
* outermost namespace contains function parameters and other special
* variables (such as FOUND), and is named after the function itself.
*/
plpgsql_ns_init();
plpgsql_ns_push(NameStr(procStruct->proname), PLPGSQL_LABEL_BLOCK);
plpgsql_DumpExecTree = false;
plpgsql_start_datums();
switch (function->fn_is_trigger)
{
case PLPGSQL_NOT_TRIGGER:
/*
* Fetch info about the procedure's parameters. Allocations aren't
* needed permanently, so make them in tmp cxt.
*
* We also need to resolve any polymorphic input or output
* argument types. In validation mode we won't be able to, so we
* arbitrarily assume we are dealing with integers.
*/
MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
numargs = get_func_arg_info(procTup,
&argtypes, &argnames, &argmodes);
plpgsql_resolve_polymorphic_argtypes(numargs, argtypes, argmodes,
fcinfo->flinfo->fn_expr,
forValidator,
plpgsql_error_funcname);
in_arg_varnos = (int *) palloc(numargs * sizeof(int));
out_arg_variables = (PLpgSQL_variable **) palloc(numargs * sizeof(PLpgSQL_variable *));
MemoryContextSwitchTo(func_cxt);
/*
* Create the variables for the procedure's parameters.
*/
for (i = 0; i < numargs; i++)
{
char buf[32];
Oid argtypeid = argtypes[i];
char argmode = argmodes ? argmodes[i] : PROARGMODE_IN;
PLpgSQL_type *argdtype;
PLpgSQL_variable *argvariable;
PLpgSQL_nsitem_type argitemtype;
/* Create $n name for variable */
snprintf(buf, sizeof(buf), "$%d", i + 1);
/* Create datatype info */
argdtype = plpgsql_build_datatype(argtypeid,
-1,
function->fn_input_collation);
/* Disallow pseudotype argument */
/* (note we already replaced polymorphic types) */
/* (build_variable would do this, but wrong message) */
if (argdtype->ttype == PLPGSQL_TTYPE_PSEUDO)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("PL/pgSQL functions cannot accept type %s",
format_type_be(argtypeid))));
/*
* Build variable and add to datum list. If there's a name
* for the argument, use that as refname, else use $n name.
*/
argvariable = plpgsql_build_variable((argnames &&
argnames[i][0] != '\0') ?
argnames[i] : buf,
0, argdtype, false);
if (argvariable->dtype == PLPGSQL_DTYPE_VAR)
{
argitemtype = PLPGSQL_NSTYPE_VAR;
}
else
{
Assert(argvariable->dtype == PLPGSQL_DTYPE_REC);
argitemtype = PLPGSQL_NSTYPE_REC;
}
/* Remember arguments in appropriate arrays */
switch (argmode)
{
/* input modes */
case PROARGMODE_IN:
case PROARGMODE_VARIADIC:
in_arg_varnos[num_in_args++] = argvariable->dno;
break;
/* output modes */
case PROARGMODE_OUT:
case PROARGMODE_TABLE:
out_arg_variables[num_out_args++] = argvariable;
break;
/* both */
case PROARGMODE_INOUT:
in_arg_varnos[num_in_args++] = argvariable->dno;
out_arg_variables[num_out_args++] = argvariable;
break;
default:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("plpgsql functions do not support argmode '%c'",
argmode)));
break;
}
/* Add to namespace under the $n name */
add_parameter_name(argitemtype, argvariable->dno, buf);
/* If there's a name for the argument, make an alias */
if (argnames && argnames[i][0] != '\0')
add_parameter_name(argitemtype, argvariable->dno,
argnames[i]);
}
/*
* If there's just one OUT parameter, out_param_varno points
* directly to it. If there's more than one, build a row that
* holds all of them. Procedures return a row even for one OUT
* parameter.
*/
if (num_out_args > 1 ||
(num_out_args == 1 && function->fn_prokind == PROKIND_PROCEDURE))
{
PLpgSQL_row *row = build_row_from_vars(out_arg_variables,
num_out_args);
plpgsql_adddatum((PLpgSQL_datum *) row);
function->out_param_varno = row->dno;
}
else if (num_out_args == 1)
function->out_param_varno = out_arg_variables[0]->dno;
/*
* Check for a polymorphic returntype. If found, use the actual
* returntype type from the caller's FuncExpr node, if we have
* one. (In validation mode we arbitrarily assume we are dealing
* with integers.)
*
* Note: errcode is FEATURE_NOT_SUPPORTED because it should always
* work; if it doesn't we're in some context that fails to make
* the info available.
*/
rettypeid = procStruct->prorettype;
if (IsPolymorphicType(rettypeid))
{
if (forValidator)
{
if (rettypeid == ANYARRAYOID)
rettypeid = INT4ARRAYOID;
else if (rettypeid == ANYRANGEOID)
rettypeid = INT4RANGEOID;
else /* ANYELEMENT or ANYNONARRAY */
rettypeid = INT4OID;
/* XXX what could we use for ANYENUM? */
}
else
{
rettypeid = get_fn_expr_rettype(fcinfo->flinfo);
if (!OidIsValid(rettypeid))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("could not determine actual return type "
"for polymorphic function \"%s\"",
plpgsql_error_funcname)));
}
}
/*
* Normal function has a defined returntype
*/
function->fn_rettype = rettypeid;
function->fn_retset = procStruct->proretset;
/*
* Lookup the function's return type
*/
typeTup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(rettypeid));
if (!HeapTupleIsValid(typeTup))
elog(ERROR, "cache lookup failed for type %u", rettypeid);
typeStruct = (Form_pg_type) GETSTRUCT(typeTup);
/* Disallow pseudotype result, except VOID or RECORD */
/* (note we already replaced polymorphic types) */
if (typeStruct->typtype == TYPTYPE_PSEUDO)
{
if (rettypeid == VOIDOID ||
rettypeid == RECORDOID)
/* okay */ ;
else if (rettypeid == TRIGGEROID || rettypeid == EVTTRIGGEROID)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("trigger functions can only be called as triggers")));
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("PL/pgSQL functions cannot return type %s",
format_type_be(rettypeid))));
}
function->fn_retistuple = type_is_rowtype(rettypeid);
function->fn_retisdomain = (typeStruct->typtype == TYPTYPE_DOMAIN);
function->fn_retbyval = typeStruct->typbyval;
function->fn_rettyplen = typeStruct->typlen;
/*
* install $0 reference, but only for polymorphic return types,
* and not when the return is specified through an output
* parameter.
*/
if (IsPolymorphicType(procStruct->prorettype) &&
num_out_args == 0)
{
(void) plpgsql_build_variable("$0", 0,
build_datatype(typeTup,
-1,
function->fn_input_collation),
true);
}
ReleaseSysCache(typeTup);
break;
case PLPGSQL_DML_TRIGGER:
/* Trigger procedure's return type is unknown yet */
function->fn_rettype = InvalidOid;
function->fn_retbyval = false;
function->fn_retistuple = true;
function->fn_retisdomain = false;
function->fn_retset = false;
/* shouldn't be any declared arguments */
if (procStruct->pronargs != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("trigger functions cannot have declared arguments"),
errhint("The arguments of the trigger can be accessed through TG_NARGS and TG_ARGV instead.")));
/* Add the record for referencing NEW ROW */
rec = plpgsql_build_record("new", 0, NULL, RECORDOID, true);
function->new_varno = rec->dno;
/* Add the record for referencing OLD ROW */
rec = plpgsql_build_record("old", 0, NULL, RECORDOID, true);
function->old_varno = rec->dno;
/* Add the variable tg_name */
var = plpgsql_build_variable("tg_name", 0,
plpgsql_build_datatype(NAMEOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_NAME;
/* Add the variable tg_when */
var = plpgsql_build_variable("tg_when", 0,
plpgsql_build_datatype(TEXTOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_WHEN;
/* Add the variable tg_level */
var = plpgsql_build_variable("tg_level", 0,
plpgsql_build_datatype(TEXTOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_LEVEL;
/* Add the variable tg_op */
var = plpgsql_build_variable("tg_op", 0,
plpgsql_build_datatype(TEXTOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_OP;
/* Add the variable tg_relid */
var = plpgsql_build_variable("tg_relid", 0,
plpgsql_build_datatype(OIDOID,
-1,
InvalidOid),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_RELID;
/* Add the variable tg_relname */
var = plpgsql_build_variable("tg_relname", 0,
plpgsql_build_datatype(NAMEOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_TABLE_NAME;
/* tg_table_name is now preferred to tg_relname */
var = plpgsql_build_variable("tg_table_name", 0,
plpgsql_build_datatype(NAMEOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_TABLE_NAME;
/* add the variable tg_table_schema */
var = plpgsql_build_variable("tg_table_schema", 0,
plpgsql_build_datatype(NAMEOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_TABLE_SCHEMA;
/* Add the variable tg_nargs */
var = plpgsql_build_variable("tg_nargs", 0,
plpgsql_build_datatype(INT4OID,
-1,
InvalidOid),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_NARGS;
/* Add the variable tg_argv */
var = plpgsql_build_variable("tg_argv", 0,
plpgsql_build_datatype(TEXTARRAYOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_ARGV;
break;
case PLPGSQL_EVENT_TRIGGER:
function->fn_rettype = VOIDOID;
function->fn_retbyval = false;
function->fn_retistuple = true;
function->fn_retisdomain = false;
function->fn_retset = false;
/* shouldn't be any declared arguments */
if (procStruct->pronargs != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("event trigger functions cannot have declared arguments")));
/* Add the variable tg_event */
var = plpgsql_build_variable("tg_event", 0,
plpgsql_build_datatype(TEXTOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_EVENT;
/* Add the variable tg_tag */
var = plpgsql_build_variable("tg_tag", 0,
plpgsql_build_datatype(TEXTOID,
-1,
function->fn_input_collation),
true);
Assert(var->dtype == PLPGSQL_DTYPE_VAR);
var->dtype = PLPGSQL_DTYPE_PROMISE;
((PLpgSQL_var *) var)->promise = PLPGSQL_PROMISE_TG_TAG;
break;
default:
elog(ERROR, "unrecognized function typecode: %d",
(int) function->fn_is_trigger);
break;
}
/* Remember if function is STABLE/IMMUTABLE */
function->fn_readonly = (procStruct->provolatile != PROVOLATILE_VOLATILE);
/*
* Create the magic FOUND variable.
*/
var = plpgsql_build_variable("found", 0,
plpgsql_build_datatype(BOOLOID,
-1,
InvalidOid),
true);
function->found_varno = var->dno;
/*
* Now parse the function's text
*/
parse_rc = plpgsql_yyparse();
if (parse_rc != 0)
elog(ERROR, "plpgsql parser returned %d", parse_rc);
function->action = plpgsql_parse_result;
plpgsql_scanner_finish();
pfree(proc_source);
/*
* If it has OUT parameters or returns VOID or returns a set, we allow
* control to fall off the end without an explicit RETURN statement. The
* easiest way to implement this is to add a RETURN statement to the end
* of the statement list during parsing.
*/
if (num_out_args > 0 || function->fn_rettype == VOIDOID ||
function->fn_retset)
add_dummy_return(function);
/*
* Complete the function's info
*/
function->fn_nargs = procStruct->pronargs;
for (i = 0; i < function->fn_nargs; i++)
function->fn_argvarnos[i] = in_arg_varnos[i];
plpgsql_finish_datums(function);
/* Debug dump for completed functions */
if (plpgsql_DumpExecTree)
plpgsql_dumptree(function);
/*
* add it to the hash table
*/
plpgsql_HashTableInsert(function, hashkey);
/*
* Pop the error context stack
*/
error_context_stack = plerrcontext.previous;
plpgsql_error_funcname = NULL;
plpgsql_check_syntax = false;
MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
plpgsql_compile_tmp_cxt = NULL;
return function;
}
/* ----------
* plpgsql_compile_inline Make an execution tree for an anonymous code block.
*
* Note: this is generally parallel to do_compile(); is it worth trying to
* merge the two?
*
* Note: we assume the block will be thrown away so there is no need to build
* persistent data structures.
* ----------
*/
PLpgSQL_function *
plpgsql_compile_inline(char *proc_source)
{
char *func_name = "inline_code_block";
PLpgSQL_function *function;
ErrorContextCallback plerrcontext;
PLpgSQL_variable *var;
int parse_rc;
MemoryContext func_cxt;
/*
* Setup the scanner input and error info. We assume that this function
* cannot be invoked recursively, so there's no need to save and restore
* the static variables used here.
*/
plpgsql_scanner_init(proc_source);
plpgsql_error_funcname = func_name;
/*
* Setup error traceback support for ereport()
*/
plerrcontext.callback = plpgsql_compile_error_callback;
plerrcontext.arg = proc_source;
plerrcontext.previous = error_context_stack;
error_context_stack = &plerrcontext;
/* Do extra syntax checking if check_function_bodies is on */
plpgsql_check_syntax = check_function_bodies;
/* Function struct does not live past current statement */
function = (PLpgSQL_function *) palloc0(sizeof(PLpgSQL_function));
plpgsql_curr_compile = function;
/*
* All the rest of the compile-time storage (e.g. parse tree) is kept in
* its own memory context, so it can be reclaimed easily.
*/
func_cxt = AllocSetContextCreate(CurrentMemoryContext,
"PL/pgSQL inline code context",
ALLOCSET_DEFAULT_SIZES);
plpgsql_compile_tmp_cxt = MemoryContextSwitchTo(func_cxt);
function->fn_signature = pstrdup(func_name);
function->fn_is_trigger = PLPGSQL_NOT_TRIGGER;
function->fn_input_collation = InvalidOid;
function->fn_cxt = func_cxt;
function->out_param_varno = -1; /* set up for no OUT param */
function->resolve_option = plpgsql_variable_conflict;
function->print_strict_params = plpgsql_print_strict_params;
/*
* don't do extra validation for inline code as we don't want to add spam
* at runtime
*/
function->extra_warnings = 0;
function->extra_errors = 0;
function->nstatements = 0;
plpgsql_ns_init();
plpgsql_ns_push(func_name, PLPGSQL_LABEL_BLOCK);
plpgsql_DumpExecTree = false;
plpgsql_start_datums();
/* Set up as though in a function returning VOID */
function->fn_rettype = VOIDOID;
function->fn_retset = false;
function->fn_retistuple = false;
function->fn_retisdomain = false;
function->fn_prokind = PROKIND_FUNCTION;
/* a bit of hardwired knowledge about type VOID here */
function->fn_retbyval = true;
function->fn_rettyplen = sizeof(int32);
/*
* Remember if function is STABLE/IMMUTABLE. XXX would it be better to
* set this true inside a read-only transaction? Not clear.
*/
function->fn_readonly = false;
/*
* Create the magic FOUND variable.
*/
var = plpgsql_build_variable("found", 0,
plpgsql_build_datatype(BOOLOID,
-1,
InvalidOid),
true);
function->found_varno = var->dno;
/*
* Now parse the function's text
*/
parse_rc = plpgsql_yyparse();
if (parse_rc != 0)
elog(ERROR, "plpgsql parser returned %d", parse_rc);
function->action = plpgsql_parse_result;
plpgsql_scanner_finish();
/*
* If it returns VOID (always true at the moment), we allow control to
* fall off the end without an explicit RETURN statement.
*/
if (function->fn_rettype == VOIDOID)
add_dummy_return(function);
/*
* Complete the function's info
*/
function->fn_nargs = 0;
plpgsql_finish_datums(function);
/*
* Pop the error context stack
*/
error_context_stack = plerrcontext.previous;
plpgsql_error_funcname = NULL;
plpgsql_check_syntax = false;
MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
plpgsql_compile_tmp_cxt = NULL;
return function;
}
/*
* error context callback to let us supply a call-stack traceback.
* If we are validating or executing an anonymous code block, the function
* source text is passed as an argument.
*/
static void
plpgsql_compile_error_callback(void *arg)
{
if (arg)
{
/*
* Try to convert syntax error position to reference text of original
* CREATE FUNCTION or DO command.
*/
if (function_parse_error_transpose((const char *) arg))
return;
/*
* Done if a syntax error position was reported; otherwise we have to
* fall back to a "near line N" report.
*/
}
if (plpgsql_error_funcname)
errcontext("compilation of PL/pgSQL function \"%s\" near line %d",
plpgsql_error_funcname, plpgsql_latest_lineno());
}
/*
* Add a name for a function parameter to the function's namespace
*/
static void
add_parameter_name(PLpgSQL_nsitem_type itemtype, int itemno, const char *name)
{
/*
* Before adding the name, check for duplicates. We need this even though
* functioncmds.c has a similar check, because that code explicitly
* doesn't complain about conflicting IN and OUT parameter names. In
* plpgsql, such names are in the same namespace, so there is no way to
* disambiguate.
*/
if (plpgsql_ns_lookup(plpgsql_ns_top(), true,
name, NULL, NULL,
NULL) != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("parameter name \"%s\" used more than once",
name)));
/* OK, add the name */
plpgsql_ns_additem(itemtype, itemno, name);
}
/*
* Add a dummy RETURN statement to the given function's body
*/
static void
add_dummy_return(PLpgSQL_function *function)
{
/*
* If the outer block has an EXCEPTION clause, we need to make a new outer
* block, since the added RETURN shouldn't act like it is inside the
* EXCEPTION clause.
*/
if (function->action->exceptions != NULL)
{
PLpgSQL_stmt_block *new;
new = palloc0(sizeof(PLpgSQL_stmt_block));
new->cmd_type = PLPGSQL_STMT_BLOCK;
new->stmtid = ++function->nstatements;
new->body = list_make1(function->action);
function->action = new;
}
if (function->action->body == NIL ||
((PLpgSQL_stmt *) llast(function->action->body))->cmd_type != PLPGSQL_STMT_RETURN)
{
PLpgSQL_stmt_return *new;
new = palloc0(sizeof(PLpgSQL_stmt_return));
new->cmd_type = PLPGSQL_STMT_RETURN;
new->stmtid = ++function->nstatements;
new->expr = NULL;
new->retvarno = function->out_param_varno;
function->action->body = lappend(function->action->body, new);
}
}
/*
* plpgsql_parser_setup set up parser hooks for dynamic parameters
*
* Note: this routine, and the hook functions it prepares for, are logically
* part of plpgsql parsing. But they actually run during function execution,
* when we are ready to evaluate a SQL query or expression that has not
* previously been parsed and planned.
*/
void
plpgsql_parser_setup(struct ParseState *pstate, PLpgSQL_expr *expr)
{
pstate->p_pre_columnref_hook = plpgsql_pre_column_ref;
pstate->p_post_columnref_hook = plpgsql_post_column_ref;
pstate->p_paramref_hook = plpgsql_param_ref;
/* no need to use p_coerce_param_hook */
pstate->p_ref_hook_state = (void *) expr;
}
/*
* plpgsql_pre_column_ref parser callback before parsing a ColumnRef
*/
static Node *
plpgsql_pre_column_ref(ParseState *pstate, ColumnRef *cref)
{
PLpgSQL_expr *expr = (PLpgSQL_expr *) pstate->p_ref_hook_state;
if (expr->func->resolve_option == PLPGSQL_RESOLVE_VARIABLE)
return resolve_column_ref(pstate, expr, cref, false);
else
return NULL;
}
/*
* plpgsql_post_column_ref parser callback after parsing a ColumnRef
*/
static Node *
plpgsql_post_column_ref(ParseState *pstate, ColumnRef *cref, Node *var)
{
PLpgSQL_expr *expr = (PLpgSQL_expr *) pstate->p_ref_hook_state;
Node *myvar;
if (expr->func->resolve_option == PLPGSQL_RESOLVE_VARIABLE)
return NULL; /* we already found there's no match */
if (expr->func->resolve_option == PLPGSQL_RESOLVE_COLUMN && var != NULL)
return NULL; /* there's a table column, prefer that */
/*
* If we find a record/row variable but can't match a field name, throw
* error if there was no core resolution for the ColumnRef either. In
* that situation, the reference is inevitably going to fail, and
* complaining about the record/row variable is likely to be more on-point
* than the core parser's error message. (It's too bad we don't have
* access to transformColumnRef's internal crerr state here, as in case of
* a conflict with a table name this could still be less than the most
* helpful error message possible.)
*/
myvar = resolve_column_ref(pstate, expr, cref, (var == NULL));
if (myvar != NULL && var != NULL)
{
/*
* We could leave it to the core parser to throw this error, but we
* can add a more useful detail message than the core could.
*/
ereport(ERROR,
(errcode(ERRCODE_AMBIGUOUS_COLUMN),
errmsg("column reference \"%s\" is ambiguous",
NameListToString(cref->fields)),
errdetail("It could refer to either a PL/pgSQL variable or a table column."),
parser_errposition(pstate, cref->location)));
}
return myvar;
}
/*
* plpgsql_param_ref parser callback for ParamRefs ($n symbols)
*/
static Node *
plpgsql_param_ref(ParseState *pstate, ParamRef *pref)
{
PLpgSQL_expr *expr = (PLpgSQL_expr *) pstate->p_ref_hook_state;
char pname[32];
PLpgSQL_nsitem *nse;
snprintf(pname, sizeof(pname), "$%d", pref->number);
nse = plpgsql_ns_lookup(expr->ns, false,
pname, NULL, NULL,
NULL);
if (nse == NULL)
return NULL; /* name not known to plpgsql */
return make_datum_param(expr, nse->itemno, pref->location);
}
/*
* resolve_column_ref attempt to resolve a ColumnRef as a plpgsql var
*
* Returns the translated node structure, or NULL if name not found
*
* error_if_no_field tells whether to throw error or quietly return NULL if
* we are able to match a record/row name but don't find a field name match.
*/
static Node *
resolve_column_ref(ParseState *pstate, PLpgSQL_expr *expr,
ColumnRef *cref, bool error_if_no_field)
{
PLpgSQL_execstate *estate;
PLpgSQL_nsitem *nse;
const char *name1;
const char *name2 = NULL;
const char *name3 = NULL;
const char *colname = NULL;
int nnames;
int nnames_scalar = 0;
int nnames_wholerow = 0;
int nnames_field = 0;
/*
* We use the function's current estate to resolve parameter data types.
* This is really pretty bogus because there is no provision for updating
* plans when those types change ...
*/
estate = expr->func->cur_estate;
/*----------
* The allowed syntaxes are:
*
* A Scalar variable reference, or whole-row record reference.
* A.B Qualified scalar or whole-row reference, or field reference.
* A.B.C Qualified record field reference.
* A.* Whole-row record reference.
* A.B.* Qualified whole-row record reference.
*----------
*/
switch (list_length(cref->fields))
{
case 1:
{
Node *field1 = (Node *) linitial(cref->fields);
Assert(IsA(field1, String));
name1 = strVal(field1);
nnames_scalar = 1;
nnames_wholerow = 1;
break;
}
case 2:
{
Node *field1 = (Node *) linitial(cref->fields);
Node *field2 = (Node *) lsecond(cref->fields);
Assert(IsA(field1, String));
name1 = strVal(field1);
/* Whole-row reference? */
if (IsA(field2, A_Star))
{
/* Set name2 to prevent matches to scalar variables */
name2 = "*";
nnames_wholerow = 1;
break;
}
Assert(IsA(field2, String));
name2 = strVal(field2);
colname = name2;
nnames_scalar = 2;
nnames_wholerow = 2;
nnames_field = 1;
break;
}
case 3:
{
Node *field1 = (Node *) linitial(cref->fields);
Node *field2 = (Node *) lsecond(cref->fields);
Node *field3 = (Node *) lthird(cref->fields);
Assert(IsA(field1, String));
name1 = strVal(field1);
Assert(IsA(field2, String));
name2 = strVal(field2);
/* Whole-row reference? */
if (IsA(field3, A_Star))
{
/* Set name3 to prevent matches to scalar variables */
name3 = "*";
nnames_wholerow = 2;
break;
}
Assert(IsA(field3, String));
name3 = strVal(field3);
colname = name3;
nnames_field = 2;
break;
}
default:
/* too many names, ignore */
return NULL;
}
nse = plpgsql_ns_lookup(expr->ns, false,
name1, name2, name3,
&nnames);
if (nse == NULL)
return NULL; /* name not known to plpgsql */
switch (nse->itemtype)
{
case PLPGSQL_NSTYPE_VAR:
if (nnames == nnames_scalar)
return make_datum_param(expr, nse->itemno, cref->location);
break;
case PLPGSQL_NSTYPE_REC:
if (nnames == nnames_wholerow)
return make_datum_param(expr, nse->itemno, cref->location);
if (nnames == nnames_field)
{
/* colname could be a field in this record */
PLpgSQL_rec *rec = (PLpgSQL_rec *) estate->datums[nse->itemno];
int i;
/* search for a datum referencing this field */
i = rec->firstfield;
while (i >= 0)
{
PLpgSQL_recfield *fld = (PLpgSQL_recfield *) estate->datums[i];
Assert(fld->dtype == PLPGSQL_DTYPE_RECFIELD &&
fld->recparentno == nse->itemno);
if (strcmp(fld->fieldname, colname) == 0)
{
return make_datum_param(expr, i, cref->location);
}
i = fld->nextfield;
}
/*
* We should not get here, because a RECFIELD datum should
* have been built at parse time for every possible qualified
* reference to fields of this record. But if we do, handle
* it like field-not-found: throw error or return NULL.
*/
if (error_if_no_field)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("record \"%s\" has no field \"%s\"",
(nnames_field == 1) ? name1 : name2,
colname),
parser_errposition(pstate, cref->location)));
}
break;
default:
elog(ERROR, "unrecognized plpgsql itemtype: %d", nse->itemtype);
}
/* Name format doesn't match the plpgsql variable type */
return NULL;
}
/*
* Helper for columnref parsing: build a Param referencing a plpgsql datum,
* and make sure that that datum is listed in the expression's paramnos.
*/
static Node *
make_datum_param(PLpgSQL_expr *expr, int dno, int location)
{
PLpgSQL_execstate *estate;
PLpgSQL_datum *datum;
Param *param;
MemoryContext oldcontext;
/* see comment in resolve_column_ref */
estate = expr->func->cur_estate;
Assert(dno >= 0 && dno < estate->ndatums);
datum = estate->datums[dno];
/*
* Bitmapset must be allocated in function's permanent memory context
*/
oldcontext = MemoryContextSwitchTo(expr->func->fn_cxt);
expr->paramnos = bms_add_member(expr->paramnos, dno);
MemoryContextSwitchTo(oldcontext);
param = makeNode(Param);
param->paramkind = PARAM_EXTERN;
param->paramid = dno + 1;
plpgsql_exec_get_datum_type_info(estate,
datum,
¶m->paramtype,
¶m->paramtypmod,
¶m->paramcollid);
param->location = location;
return (Node *) param;
}
/* ----------
* plpgsql_parse_word The scanner calls this to postparse
* any single word that is not a reserved keyword.
*
* word1 is the downcased/dequoted identifier; it must be palloc'd in the
* function's long-term memory context.
*
* yytxt is the original token text; we need this to check for quoting,
* so that later checks for unreserved keywords work properly.
*
* We attempt to recognize the token as a variable only if lookup is true
* and the plpgsql_IdentifierLookup context permits it.
*
* If recognized as a variable, fill in *wdatum and return true;
* if not recognized, fill in *word and return false.
* (Note: those two pointers actually point to members of the same union,
* but for notational reasons we pass them separately.)
* ----------
*/
bool
plpgsql_parse_word(char *word1, const char *yytxt, bool lookup,
PLwdatum *wdatum, PLword *word)
{
PLpgSQL_nsitem *ns;
/*
* We should not lookup variables in DECLARE sections. In SQL
* expressions, there's no need to do so either --- lookup will happen
* when the expression is compiled.
*/
if (lookup && plpgsql_IdentifierLookup == IDENTIFIER_LOOKUP_NORMAL)
{
/*
* Do a lookup in the current namespace stack
*/
ns = plpgsql_ns_lookup(plpgsql_ns_top(), false,
word1, NULL, NULL,
NULL);
if (ns != NULL)
{
switch (ns->itemtype)
{
case PLPGSQL_NSTYPE_VAR:
case PLPGSQL_NSTYPE_REC:
wdatum->datum = plpgsql_Datums[ns->itemno];
wdatum->ident = word1;
wdatum->quoted = (yytxt[0] == '"');
wdatum->idents = NIL;
return true;
default:
/* plpgsql_ns_lookup should never return anything else */
elog(ERROR, "unrecognized plpgsql itemtype: %d",
ns->itemtype);
}
}
}
/*
* Nothing found - up to now it's a word without any special meaning for
* us.
*/
word->ident = word1;
word->quoted = (yytxt[0] == '"');
return false;
}
/* ----------
* plpgsql_parse_dblword Same lookup for two words
* separated by a dot.
* ----------
*/
bool
plpgsql_parse_dblword(char *word1, char *word2,
PLwdatum *wdatum, PLcword *cword)
{
PLpgSQL_nsitem *ns;
List *idents;
int nnames;
idents = list_make2(makeString(word1),
makeString(word2));
/*
* We should do nothing in DECLARE sections. In SQL expressions, we
* really only need to make sure that RECFIELD datums are created when
* needed.
*/
if (plpgsql_IdentifierLookup != IDENTIFIER_LOOKUP_DECLARE)
{
/*
* Do a lookup in the current namespace stack
*/
ns = plpgsql_ns_lookup(plpgsql_ns_top(), false,
word1, word2, NULL,
&nnames);
if (ns != NULL)
{
switch (ns->itemtype)
{
case PLPGSQL_NSTYPE_VAR:
/* Block-qualified reference to scalar variable. */
wdatum->datum = plpgsql_Datums[ns->itemno];
wdatum->ident = NULL;
wdatum->quoted = false; /* not used */
wdatum->idents = idents;
return true;
case PLPGSQL_NSTYPE_REC:
if (nnames == 1)
{
/*
* First word is a record name, so second word could
* be a field in this record. We build a RECFIELD
* datum whether it is or not --- any error will be
* detected later.
*/
PLpgSQL_rec *rec;
PLpgSQL_recfield *new;
rec = (PLpgSQL_rec *) (plpgsql_Datums[ns->itemno]);
new = plpgsql_build_recfield(rec, word2);
wdatum->datum = (PLpgSQL_datum *) new;
}
else
{
/* Block-qualified reference to record variable. */
wdatum->datum = plpgsql_Datums[ns->itemno];
}
wdatum->ident = NULL;
wdatum->quoted = false; /* not used */
wdatum->idents = idents;
return true;
default:
break;
}
}
}
/* Nothing found */
cword->idents = idents;
return false;
}
/* ----------
* plpgsql_parse_tripword Same lookup for three words
* separated by dots.
* ----------
*/
bool
plpgsql_parse_tripword(char *word1, char *word2, char *word3,
PLwdatum *wdatum, PLcword *cword)
{
PLpgSQL_nsitem *ns;
List *idents;
int nnames;
idents = list_make3(makeString(word1),
makeString(word2),
makeString(word3));
/*
* We should do nothing in DECLARE sections. In SQL expressions, we
* really only need to make sure that RECFIELD datums are created when
* needed.
*/
if (plpgsql_IdentifierLookup != IDENTIFIER_LOOKUP_DECLARE)
{
/*
* Do a lookup in the current namespace stack. Must find a qualified
* reference, else ignore.
*/
ns = plpgsql_ns_lookup(plpgsql_ns_top(), false,
word1, word2, word3,
&nnames);
if (ns != NULL && nnames == 2)
{
switch (ns->itemtype)
{
case PLPGSQL_NSTYPE_REC:
{
/*
* words 1/2 are a record name, so third word could be
* a field in this record.
*/
PLpgSQL_rec *rec;
PLpgSQL_recfield *new;
rec = (PLpgSQL_rec *) (plpgsql_Datums[ns->itemno]);
new = plpgsql_build_recfield(rec, word3);
wdatum->datum = (PLpgSQL_datum *) new;
wdatum->ident = NULL;
wdatum->quoted = false; /* not used */
wdatum->idents = idents;
return true;
}
default:
break;
}
}
}
/* Nothing found */
cword->idents = idents;
return false;
}
/* ----------
* plpgsql_parse_wordtype The scanner found word%TYPE. word can be
* a variable name or a basetype.
*
* Returns datatype struct, or NULL if no match found for word.
* ----------
*/
PLpgSQL_type *
plpgsql_parse_wordtype(char *ident)
{
PLpgSQL_type *dtype;
PLpgSQL_nsitem *nse;
HeapTuple typeTup;
/*
* Do a lookup in the current namespace stack
*/
nse = plpgsql_ns_lookup(plpgsql_ns_top(), false,
ident, NULL, NULL,
NULL);
if (nse != NULL)
{
switch (nse->itemtype)
{
case PLPGSQL_NSTYPE_VAR:
return ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
/* XXX perhaps allow REC/ROW here? */
default:
return NULL;
}
}
/*
* Word wasn't found in the namespace stack. Try to find a data type with
* that name, but ignore shell types and complex types.
*/
typeTup = LookupTypeName(NULL, makeTypeName(ident), NULL, false);
if (typeTup)
{
Form_pg_type typeStruct = (Form_pg_type) GETSTRUCT(typeTup);
if (!typeStruct->typisdefined ||
typeStruct->typrelid != InvalidOid)
{
ReleaseSysCache(typeTup);
return NULL;
}
dtype = build_datatype(typeTup, -1,
plpgsql_curr_compile->fn_input_collation);
ReleaseSysCache(typeTup);
return dtype;
}
/*
* Nothing found - up to now it's a word without any special meaning for
* us.
*/
return NULL;
}
/* ----------
* plpgsql_parse_cwordtype Same lookup for compositeword%TYPE
* ----------
*/
PLpgSQL_type *
plpgsql_parse_cwordtype(List *idents)
{
PLpgSQL_type *dtype = NULL;
PLpgSQL_nsitem *nse;
const char *fldname;
Oid classOid;
HeapTuple classtup = NULL;
HeapTuple attrtup = NULL;
HeapTuple typetup = NULL;
Form_pg_class classStruct;
Form_pg_attribute attrStruct;
MemoryContext oldCxt;
/* Avoid memory leaks in the long-term function context */
oldCxt = MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
if (list_length(idents) == 2)
{
/*
* Do a lookup in the current namespace stack. We don't need to check
* number of names matched, because we will only consider scalar
* variables.
*/
nse = plpgsql_ns_lookup(plpgsql_ns_top(), false,
strVal(linitial(idents)),
strVal(lsecond(idents)),
NULL,
NULL);
if (nse != NULL && nse->itemtype == PLPGSQL_NSTYPE_VAR)
{
dtype = ((PLpgSQL_var *) (plpgsql_Datums[nse->itemno]))->datatype;
goto done;
}
/*
* First word could also be a table name
*/
classOid = RelnameGetRelid(strVal(linitial(idents)));
if (!OidIsValid(classOid))
goto done;
fldname = strVal(lsecond(idents));
}
else if (list_length(idents) == 3)
{
RangeVar *relvar;
relvar = makeRangeVar(strVal(linitial(idents)),
strVal(lsecond(idents)),
-1);
/* Can't lock relation - we might not have privileges. */
classOid = RangeVarGetRelid(relvar, NoLock, true);
if (!OidIsValid(classOid))
goto done;
fldname = strVal(lthird(idents));
}
else
goto done;
classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(classOid));
if (!HeapTupleIsValid(classtup))
goto done;
classStruct = (Form_pg_class) GETSTRUCT(classtup);
/*
* It must be a relation, sequence, view, materialized view, composite
* type, or foreign table
*/
if (classStruct->relkind != RELKIND_RELATION &&
classStruct->relkind != RELKIND_SEQUENCE &&
classStruct->relkind != RELKIND_VIEW &&
classStruct->relkind != RELKIND_MATVIEW &&
classStruct->relkind != RELKIND_COMPOSITE_TYPE &&
classStruct->relkind != RELKIND_FOREIGN_TABLE &&
classStruct->relkind != RELKIND_PARTITIONED_TABLE)
goto done;
/*
* Fetch the named table field and its type
*/
attrtup = SearchSysCacheAttName(classOid, fldname);
if (!HeapTupleIsValid(attrtup))
goto done;
attrStruct = (Form_pg_attribute) GETSTRUCT(attrtup);
typetup = SearchSysCache1(TYPEOID,
ObjectIdGetDatum(attrStruct->atttypid));
if (!HeapTupleIsValid(typetup))
elog(ERROR, "cache lookup failed for type %u", attrStruct->atttypid);
/*
* Found that - build a compiler type struct in the caller's cxt and
* return it
*/
MemoryContextSwitchTo(oldCxt);
dtype = build_datatype(typetup,
attrStruct->atttypmod,
attrStruct->attcollation);
MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
done:
if (HeapTupleIsValid(classtup))
ReleaseSysCache(classtup);
if (HeapTupleIsValid(attrtup))
ReleaseSysCache(attrtup);
if (HeapTupleIsValid(typetup))
ReleaseSysCache(typetup);
MemoryContextSwitchTo(oldCxt);
return dtype;
}
/* ----------
* plpgsql_parse_wordrowtype Scanner found word%ROWTYPE.
* So word must be a table name.
* ----------
*/
PLpgSQL_type *
plpgsql_parse_wordrowtype(char *ident)
{
Oid classOid;
/* Lookup the relation */
classOid = RelnameGetRelid(ident);
if (!OidIsValid(classOid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_TABLE),
errmsg("relation \"%s\" does not exist", ident)));
/* Build and return the row type struct */
return plpgsql_build_datatype(get_rel_type_id(classOid), -1, InvalidOid);
}
/* ----------
* plpgsql_parse_cwordrowtype Scanner found compositeword%ROWTYPE.
* So word must be a namespace qualified table name.
* ----------
*/
PLpgSQL_type *
plpgsql_parse_cwordrowtype(List *idents)
{
Oid classOid;
RangeVar *relvar;
MemoryContext oldCxt;
if (list_length(idents) != 2)
return NULL;
/* Avoid memory leaks in long-term function context */
oldCxt = MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
/* Look up relation name. Can't lock it - we might not have privileges. */
relvar = makeRangeVar(strVal(linitial(idents)),
strVal(lsecond(idents)),
-1);
classOid = RangeVarGetRelid(relvar, NoLock, false);
MemoryContextSwitchTo(oldCxt);
/* Build and return the row type struct */
return plpgsql_build_datatype(get_rel_type_id(classOid), -1, InvalidOid);
}
/*
* plpgsql_build_variable - build a datum-array entry of a given
* datatype
*
* The returned struct may be a PLpgSQL_var or PLpgSQL_rec
* depending on the given datatype, and is allocated via
* palloc. The struct is automatically added to the current datum
* array, and optionally to the current namespace.
*/
PLpgSQL_variable *
plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype,
bool add2namespace)
{
PLpgSQL_variable *result;
switch (dtype->ttype)
{
case PLPGSQL_TTYPE_SCALAR:
{
/* Ordinary scalar datatype */
PLpgSQL_var *var;
var = palloc0(sizeof(PLpgSQL_var));
var->dtype = PLPGSQL_DTYPE_VAR;
var->refname = pstrdup(refname);
var->lineno = lineno;
var->datatype = dtype;
/* other fields are left as 0, might be changed by caller */
/* preset to NULL */
var->value = 0;
var->isnull = true;
var->freeval = false;
plpgsql_adddatum((PLpgSQL_datum *) var);
if (add2namespace)
plpgsql_ns_additem(PLPGSQL_NSTYPE_VAR,
var->dno,
refname);
result = (PLpgSQL_variable *) var;
break;
}
case PLPGSQL_TTYPE_REC:
{
/* Composite type -- build a record variable */
PLpgSQL_rec *rec;
rec = plpgsql_build_record(refname, lineno,
dtype, dtype->typoid,
add2namespace);
result = (PLpgSQL_variable *) rec;
break;
}
case PLPGSQL_TTYPE_PSEUDO:
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("variable \"%s\" has pseudo-type %s",
refname, format_type_be(dtype->typoid))));
result = NULL; /* keep compiler quiet */
break;
default:
elog(ERROR, "unrecognized ttype: %d", dtype->ttype);
result = NULL; /* keep compiler quiet */
break;
}
return result;
}
/*
* Build empty named record variable, and optionally add it to namespace
*/
PLpgSQL_rec *
plpgsql_build_record(const char *refname, int lineno,
PLpgSQL_type *dtype, Oid rectypeid,
bool add2namespace)
{
PLpgSQL_rec *rec;
rec = palloc0(sizeof(PLpgSQL_rec));
rec->dtype = PLPGSQL_DTYPE_REC;
rec->refname = pstrdup(refname);
rec->lineno = lineno;
/* other fields are left as 0, might be changed by caller */
rec->datatype = dtype;
rec->rectypeid = rectypeid;
rec->firstfield = -1;
rec->erh = NULL;
plpgsql_adddatum((PLpgSQL_datum *) rec);
if (add2namespace)
plpgsql_ns_additem(PLPGSQL_NSTYPE_REC, rec->dno, rec->refname);
return rec;
}
/*
* Build a row-variable data structure given the component variables.
* Include a rowtupdesc, since we will need to materialize the row result.
*/
static PLpgSQL_row *
build_row_from_vars(PLpgSQL_variable **vars, int numvars)
{
PLpgSQL_row *row;
int i;
row = palloc0(sizeof(PLpgSQL_row));
row->dtype = PLPGSQL_DTYPE_ROW;
row->refname = "(unnamed row)";
row->lineno = -1;
row->rowtupdesc = CreateTemplateTupleDesc(numvars);
row->nfields = numvars;
row->fieldnames = palloc(numvars * sizeof(char *));
row->varnos = palloc(numvars * sizeof(int));
for (i = 0; i < numvars; i++)
{
PLpgSQL_variable *var = vars[i];
Oid typoid;
int32 typmod;
Oid typcoll;
/* Member vars of a row should never be const */
Assert(!var->isconst);
switch (var->dtype)
{
case PLPGSQL_DTYPE_VAR:
case PLPGSQL_DTYPE_PROMISE:
typoid = ((PLpgSQL_var *) var)->datatype->typoid;
typmod = ((PLpgSQL_var *) var)->datatype->atttypmod;
typcoll = ((PLpgSQL_var *) var)->datatype->collation;
break;
case PLPGSQL_DTYPE_REC:
typoid = ((PLpgSQL_rec *) var)->rectypeid;
typmod = -1; /* don't know typmod, if it's used at all */
typcoll = InvalidOid; /* composite types have no collation */
break;
default:
elog(ERROR, "unrecognized dtype: %d", var->dtype);
typoid = InvalidOid; /* keep compiler quiet */
typmod = 0;
typcoll = InvalidOid;
break;
}
row->fieldnames[i] = var->refname;
row->varnos[i] = var->dno;
TupleDescInitEntry(row->rowtupdesc, i + 1,
var->refname,
typoid, typmod,
0);
TupleDescInitEntryCollation(row->rowtupdesc, i + 1, typcoll);
}
return row;
}
/*
* Build a RECFIELD datum for the named field of the specified record variable
*
* If there's already such a datum, just return it; we don't need duplicates.
*/
PLpgSQL_recfield *
plpgsql_build_recfield(PLpgSQL_rec *rec, const char *fldname)
{
PLpgSQL_recfield *recfield;
int i;
/* search for an existing datum referencing this field */
i = rec->firstfield;
while (i >= 0)
{
PLpgSQL_recfield *fld = (PLpgSQL_recfield *) plpgsql_Datums[i];
Assert(fld->dtype == PLPGSQL_DTYPE_RECFIELD &&
fld->recparentno == rec->dno);
if (strcmp(fld->fieldname, fldname) == 0)
return fld;
i = fld->nextfield;
}
/* nope, so make a new one */
recfield = palloc0(sizeof(PLpgSQL_recfield));
recfield->dtype = PLPGSQL_DTYPE_RECFIELD;
recfield->fieldname = pstrdup(fldname);
recfield->recparentno = rec->dno;
recfield->rectupledescid = INVALID_TUPLEDESC_IDENTIFIER;
plpgsql_adddatum((PLpgSQL_datum *) recfield);
/* now we can link it into the parent's chain */
recfield->nextfield = rec->firstfield;
rec->firstfield = recfield->dno;
return recfield;
}
/*
* plpgsql_build_datatype
* Build PLpgSQL_type struct given type OID, typmod, and collation.
*
* If collation is not InvalidOid then it overrides the type's default
* collation. But collation is ignored if the datatype is non-collatable.
*/
PLpgSQL_type *
plpgsql_build_datatype(Oid typeOid, int32 typmod, Oid collation)
{
HeapTuple typeTup;
PLpgSQL_type *typ;
typeTup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typeOid));
if (!HeapTupleIsValid(typeTup))
elog(ERROR, "cache lookup failed for type %u", typeOid);
typ = build_datatype(typeTup, typmod, collation);
ReleaseSysCache(typeTup);
return typ;
}
/*
* Utility subroutine to make a PLpgSQL_type struct given a pg_type entry
*/
static PLpgSQL_type *
build_datatype(HeapTuple typeTup, int32 typmod, Oid collation)
{
Form_pg_type typeStruct = (Form_pg_type) GETSTRUCT(typeTup);
PLpgSQL_type *typ;
if (!typeStruct->typisdefined)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("type \"%s\" is only a shell",
NameStr(typeStruct->typname))));
typ = (PLpgSQL_type *) palloc(sizeof(PLpgSQL_type));
typ->typname = pstrdup(NameStr(typeStruct->typname));
typ->typoid = typeStruct->oid;
switch (typeStruct->typtype)
{
case TYPTYPE_BASE:
case TYPTYPE_ENUM:
case TYPTYPE_RANGE:
typ->ttype = PLPGSQL_TTYPE_SCALAR;
break;
case TYPTYPE_COMPOSITE:
typ->ttype = PLPGSQL_TTYPE_REC;
break;
case TYPTYPE_DOMAIN:
if (type_is_rowtype(typeStruct->typbasetype))
typ->ttype = PLPGSQL_TTYPE_REC;
else
typ->ttype = PLPGSQL_TTYPE_SCALAR;
break;
case TYPTYPE_PSEUDO:
if (typ->typoid == RECORDOID)
typ->ttype = PLPGSQL_TTYPE_REC;
else
typ->ttype = PLPGSQL_TTYPE_PSEUDO;
break;
default:
elog(ERROR, "unrecognized typtype: %d",
(int) typeStruct->typtype);
break;
}
typ->typlen = typeStruct->typlen;
typ->typbyval = typeStruct->typbyval;
typ->typtype = typeStruct->typtype;
typ->collation = typeStruct->typcollation;
if (OidIsValid(collation) && OidIsValid(typ->collation))
typ->collation = collation;
/* Detect if type is true array, or domain thereof */
/* NB: this is only used to decide whether to apply expand_array */
if (typeStruct->typtype == TYPTYPE_BASE)
{
/*
* This test should include what get_element_type() checks. We also
* disallow non-toastable array types (i.e. oidvector and int2vector).
*/
typ->typisarray = (typeStruct->typlen == -1 &&
OidIsValid(typeStruct->typelem) &&
typeStruct->typstorage != 'p');
}
else if (typeStruct->typtype == TYPTYPE_DOMAIN)
{
/* we can short-circuit looking up base types if it's not varlena */
typ->typisarray = (typeStruct->typlen == -1 &&
typeStruct->typstorage != 'p' &&
OidIsValid(get_base_element_type(typeStruct->typbasetype)));
}
else
typ->typisarray = false;
typ->atttypmod = typmod;
return typ;
}
/*
* plpgsql_recognize_err_condition
* Check condition name and translate it to SQLSTATE.
*
* Note: there are some cases where the same condition name has multiple
* entries in the table. We arbitrarily return the first match.
*/
int
plpgsql_recognize_err_condition(const char *condname, bool allow_sqlstate)
{
int i;
if (allow_sqlstate)
{
if (strlen(condname) == 5 &&
strspn(condname, "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ") == 5)
return MAKE_SQLSTATE(condname[0],
condname[1],
condname[2],
condname[3],
condname[4]);
}
for (i = 0; exception_label_map[i].label != NULL; i++)
{
if (strcmp(condname, exception_label_map[i].label) == 0)
return exception_label_map[i].sqlerrstate;
}
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("unrecognized exception condition \"%s\"",
condname)));
return 0; /* keep compiler quiet */
}
/*
* plpgsql_parse_err_condition
* Generate PLpgSQL_condition entry(s) for an exception condition name
*
* This has to be able to return a list because there are some duplicate
* names in the table of error code names.
*/
PLpgSQL_condition *
plpgsql_parse_err_condition(char *condname)
{
int i;
PLpgSQL_condition *new;
PLpgSQL_condition *prev;
/*
* XXX Eventually we will want to look for user-defined exception names
* here.
*/
/*
* OTHERS is represented as code 0 (which would map to '00000', but we
* have no need to represent that as an exception condition).
*/
if (strcmp(condname, "others") == 0)
{
new = palloc(sizeof(PLpgSQL_condition));
new->sqlerrstate = 0;
new->condname = condname;
new->next = NULL;
return new;
}
prev = NULL;
for (i = 0; exception_label_map[i].label != NULL; i++)
{
if (strcmp(condname, exception_label_map[i].label) == 0)
{
new = palloc(sizeof(PLpgSQL_condition));
new->sqlerrstate = exception_label_map[i].sqlerrstate;
new->condname = condname;
new->next = prev;
prev = new;
}
}
if (!prev)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("unrecognized exception condition \"%s\"",
condname)));
return prev;
}
/* ----------
* plpgsql_start_datums Initialize datum list at compile startup.
* ----------
*/
static void
plpgsql_start_datums(void)
{
datums_alloc = 128;
plpgsql_nDatums = 0;
/* This is short-lived, so needn't allocate in function's cxt */
plpgsql_Datums = MemoryContextAlloc(plpgsql_compile_tmp_cxt,
sizeof(PLpgSQL_datum *) * datums_alloc);
/* datums_last tracks what's been seen by plpgsql_add_initdatums() */
datums_last = 0;
}
/* ----------
* plpgsql_adddatum Add a variable, record or row
* to the compiler's datum list.
* ----------
*/
void
plpgsql_adddatum(PLpgSQL_datum *newdatum)
{
if (plpgsql_nDatums == datums_alloc)
{
datums_alloc *= 2;
plpgsql_Datums = repalloc(plpgsql_Datums, sizeof(PLpgSQL_datum *) * datums_alloc);
}
newdatum->dno = plpgsql_nDatums;
plpgsql_Datums[plpgsql_nDatums++] = newdatum;
}
/* ----------
* plpgsql_finish_datums Copy completed datum info into function struct.
* ----------
*/
static void
plpgsql_finish_datums(PLpgSQL_function *function)
{
Size copiable_size = 0;
int i;
function->ndatums = plpgsql_nDatums;
function->datums = palloc(sizeof(PLpgSQL_datum *) * plpgsql_nDatums);
for (i = 0; i < plpgsql_nDatums; i++)
{
function->datums[i] = plpgsql_Datums[i];
/* This must agree with copy_plpgsql_datums on what is copiable */
switch (function->datums[i]->dtype)
{
case PLPGSQL_DTYPE_VAR:
case PLPGSQL_DTYPE_PROMISE:
copiable_size += MAXALIGN(sizeof(PLpgSQL_var));
break;
case PLPGSQL_DTYPE_REC:
copiable_size += MAXALIGN(sizeof(PLpgSQL_rec));
break;
default:
break;
}
}
function->copiable_size = copiable_size;
}
/* ----------
* plpgsql_add_initdatums Make an array of the datum numbers of
* all the initializable datums created since the last call
* to this function.
*
* If varnos is NULL, we just forget any datum entries created since the
* last call.
*
* This is used around a DECLARE section to create a list of the datums
* that have to be initialized at block entry. Note that datums can also
* be created elsewhere than DECLARE, eg by a FOR-loop, but it is then
* the responsibility of special-purpose code to initialize them.
* ----------
*/
int
plpgsql_add_initdatums(int **varnos)
{
int i;
int n = 0;
/*
* The set of dtypes recognized here must match what exec_stmt_block()
* cares about (re)initializing at block entry.
*/
for (i = datums_last; i < plpgsql_nDatums; i++)
{
switch (plpgsql_Datums[i]->dtype)
{
case PLPGSQL_DTYPE_VAR:
case PLPGSQL_DTYPE_REC:
n++;
break;
default:
break;
}
}
if (varnos != NULL)
{
if (n > 0)
{
*varnos = (int *) palloc(sizeof(int) * n);
n = 0;
for (i = datums_last; i < plpgsql_nDatums; i++)
{
switch (plpgsql_Datums[i]->dtype)
{
case PLPGSQL_DTYPE_VAR:
case PLPGSQL_DTYPE_REC:
(*varnos)[n++] = plpgsql_Datums[i]->dno;
default:
break;
}
}
}
else
*varnos = NULL;
}
datums_last = plpgsql_nDatums;
return n;
}
/*
* Compute the hashkey for a given function invocation
*
* The hashkey is returned into the caller-provided storage at *hashkey.
*/
static void
compute_function_hashkey(FunctionCallInfo fcinfo,
Form_pg_proc procStruct,
PLpgSQL_func_hashkey *hashkey,
bool forValidator)
{
/* Make sure any unused bytes of the struct are zero */
MemSet(hashkey, 0, sizeof(PLpgSQL_func_hashkey));
/* get function OID */
hashkey->funcOid = fcinfo->flinfo->fn_oid;
/* get call context */
hashkey->isTrigger = CALLED_AS_TRIGGER(fcinfo);
/*
* if trigger, get its OID. In validation mode we do not know what
* relation or transition table names are intended to be used, so we leave
* trigOid zero; the hash entry built in this case will never really be
* used.
*/
if (hashkey->isTrigger && !forValidator)
{
TriggerData *trigdata = (TriggerData *) fcinfo->context;
hashkey->trigOid = trigdata->tg_trigger->tgoid;
}
/* get input collation, if known */
hashkey->inputCollation = fcinfo->fncollation;
if (procStruct->pronargs > 0)
{
/* get the argument types */
memcpy(hashkey->argtypes, procStruct->proargtypes.values,
procStruct->pronargs * sizeof(Oid));
/* resolve any polymorphic argument types */
plpgsql_resolve_polymorphic_argtypes(procStruct->pronargs,
hashkey->argtypes,
NULL,
fcinfo->flinfo->fn_expr,
forValidator,
NameStr(procStruct->proname));
}
}
/*
* This is the same as the standard resolve_polymorphic_argtypes() function,
* but with a special case for validation: assume that polymorphic arguments
* are integer, integer-array or integer-range. Also, we go ahead and report
* the error if we can't resolve the types.
*/
static void
plpgsql_resolve_polymorphic_argtypes(int numargs,
Oid *argtypes, char *argmodes,
Node *call_expr, bool forValidator,
const char *proname)
{
int i;
if (!forValidator)
{
/* normal case, pass to standard routine */
if (!resolve_polymorphic_argtypes(numargs, argtypes, argmodes,
call_expr))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("could not determine actual argument "
"type for polymorphic function \"%s\"",
proname)));
}
else
{
/* special validation case */
for (i = 0; i < numargs; i++)
{
switch (argtypes[i])
{
case ANYELEMENTOID:
case ANYNONARRAYOID:
case ANYENUMOID: /* XXX dubious */
argtypes[i] = INT4OID;
break;
case ANYARRAYOID:
argtypes[i] = INT4ARRAYOID;
break;
case ANYRANGEOID:
argtypes[i] = INT4RANGEOID;
break;
default:
break;
}
}
}
}
/*
* delete_function - clean up as much as possible of a stale function cache
*
* We can't release the PLpgSQL_function struct itself, because of the
* possibility that there are fn_extra pointers to it. We can release
* the subsidiary storage, but only if there are no active evaluations
* in progress. Otherwise we'll just leak that storage. Since the
* case would only occur if a pg_proc update is detected during a nested
* recursive call on the function, a leak seems acceptable.
*
* Note that this can be called more than once if there are multiple fn_extra
* pointers to the same function cache. Hence be careful not to do things
* twice.
*/
static void
delete_function(PLpgSQL_function *func)
{
/* remove function from hash table (might be done already) */
plpgsql_HashTableDelete(func);
/* release the function's storage if safe and not done already */
if (func->use_count == 0)
plpgsql_free_function_memory(func);
}
/* exported so we can call it from plpgsql_init() */
void
plpgsql_HashTableInit(void)
{
HASHCTL ctl;
/* don't allow double-initialization */
Assert(plpgsql_HashTable == NULL);
memset(&ctl, 0, sizeof(ctl));
ctl.keysize = sizeof(PLpgSQL_func_hashkey);
ctl.entrysize = sizeof(plpgsql_HashEnt);
plpgsql_HashTable = hash_create("PLpgSQL function hash",
FUNCS_PER_USER,
&ctl,
HASH_ELEM | HASH_BLOBS);
}
static PLpgSQL_function *
plpgsql_HashTableLookup(PLpgSQL_func_hashkey *func_key)
{
plpgsql_HashEnt *hentry;
hentry = (plpgsql_HashEnt *) hash_search(plpgsql_HashTable,
(void *) func_key,
HASH_FIND,
NULL);
if (hentry)
return hentry->function;
else
return NULL;
}
static void
plpgsql_HashTableInsert(PLpgSQL_function *function,
PLpgSQL_func_hashkey *func_key)
{
plpgsql_HashEnt *hentry;
bool found;
hentry = (plpgsql_HashEnt *) hash_search(plpgsql_HashTable,
(void *) func_key,
HASH_ENTER,
&found);
if (found)
elog(WARNING, "trying to insert a function that already exists");
hentry->function = function;
/* prepare back link from function to hashtable key */
function->fn_hashkey = &hentry->key;
}
static void
plpgsql_HashTableDelete(PLpgSQL_function *function)
{
plpgsql_HashEnt *hentry;
/* do nothing if not in table */
if (function->fn_hashkey == NULL)
return;
hentry = (plpgsql_HashEnt *) hash_search(plpgsql_HashTable,
(void *) function->fn_hashkey,
HASH_REMOVE,
NULL);
if (hentry == NULL)
elog(WARNING, "trying to delete function that does not exist");
/* remove back link, which no longer points to allocated storage */
function->fn_hashkey = NULL;
}
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