plpgsql.h

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	List	   *body;			/* List of statements */
} PLpgSQL_stmt_fori;


typedef struct
{								/* FOR statement running over SELECT	*/
	int			cmd_type;
	int			lineno;
	char	   *label;
	PLpgSQL_rec *rec;
	PLpgSQL_row *row;
	PLpgSQL_expr *query;
	List	   *body;			/* List of statements */
} PLpgSQL_stmt_fors;


typedef struct
{								/* FOR statement running over EXECUTE	*/
	int			cmd_type;
	int			lineno;
	char	   *label;
	PLpgSQL_rec *rec;
	PLpgSQL_row *row;
	PLpgSQL_expr *query;
	List	   *body;			/* List of statements */
} PLpgSQL_stmt_dynfors;


typedef struct
{								/* OPEN a curvar					*/
	int			cmd_type;
	int			lineno;
	int			curvar;
	int			cursor_options;
	PLpgSQL_row *returntype;
	PLpgSQL_expr *argquery;
	PLpgSQL_expr *query;
	PLpgSQL_expr *dynquery;
} PLpgSQL_stmt_open;


typedef struct
{								/* FETCH or MOVE statement */
	int			cmd_type;
	int			lineno;
	PLpgSQL_rec *rec;			/* target, as record or row */
	PLpgSQL_row *row;
	int			curvar;			/* cursor variable to fetch from */
	FetchDirection direction;	/* fetch direction */
	int			how_many;		/* count, if constant (expr is NULL) */
	PLpgSQL_expr *expr;			/* count, if expression */
	bool		is_move;		/* is this a fetch or move? */
} PLpgSQL_stmt_fetch;


typedef struct
{								/* CLOSE curvar						*/
	int			cmd_type;
	int			lineno;
	int			curvar;
} PLpgSQL_stmt_close;


typedef struct
{								/* EXIT or CONTINUE statement			*/
	int			cmd_type;
	int			lineno;
	bool		is_exit;		/* Is this an exit or a continue? */
	char	   *label;			/* NULL if it's an unlabelled EXIT/CONTINUE */
	PLpgSQL_expr *cond;
} PLpgSQL_stmt_exit;


typedef struct
{								/* RETURN statement			*/
	int			cmd_type;
	int			lineno;
	PLpgSQL_expr *expr;
	int			retvarno;
} PLpgSQL_stmt_return;

typedef struct
{								/* RETURN NEXT statement */
	int			cmd_type;
	int			lineno;
	PLpgSQL_expr *expr;
	int			retvarno;
} PLpgSQL_stmt_return_next;

typedef struct
{								/* RETURN QUERY statement */
	int			cmd_type;
	int			lineno;
	PLpgSQL_expr *query;
} PLpgSQL_stmt_return_query;

typedef struct
{								/* RAISE statement			*/
	int			cmd_type;
	int			lineno;
	int			elog_level;
	char	   *message;
	List	   *params;			/* list of expressions */
} PLpgSQL_stmt_raise;


typedef struct
{								/* Generic SQL statement to execute */
	int			cmd_type;
	int			lineno;
	PLpgSQL_expr *sqlstmt;
	bool		mod_stmt;		/* is the stmt INSERT/UPDATE/DELETE? */
	/* note: mod_stmt is set when we plan the query */
	bool		into;			/* INTO supplied? */
	bool		strict;			/* INTO STRICT flag */
	PLpgSQL_rec *rec;			/* INTO target, if record */
	PLpgSQL_row *row;			/* INTO target, if row */
} PLpgSQL_stmt_execsql;


typedef struct
{								/* Dynamic SQL string to execute */
	int			cmd_type;
	int			lineno;
	PLpgSQL_expr *query;		/* string expression */
	bool		into;			/* INTO supplied? */
	bool		strict;			/* INTO STRICT flag */
	PLpgSQL_rec *rec;			/* INTO target, if record */
	PLpgSQL_row *row;			/* INTO target, if row */
} PLpgSQL_stmt_dynexecute;


typedef struct PLpgSQL_func_hashkey
{								/* Hash lookup key for functions */
	Oid			funcOid;

	/*
	 * For a trigger function, the OID of the relation triggered on is part of
	 * the hashkey --- we want to compile the trigger separately for each
	 * relation it is used with, in case the rowtype is different.	Zero if
	 * not called as a trigger.
	 */
	Oid			trigrelOid;

	/*
	 * We include actual argument types in the hash key to support polymorphic
	 * PLpgSQL functions.  Be careful that extra positions are zeroed!
	 */
	Oid			argtypes[FUNC_MAX_ARGS];
} PLpgSQL_func_hashkey;


typedef struct PLpgSQL_function
{								/* Complete compiled function	  */
	char	   *fn_name;
	Oid			fn_oid;
	TransactionId fn_xmin;
	ItemPointerData fn_tid;
	int			fn_functype;
	PLpgSQL_func_hashkey *fn_hashkey;	/* back-link to hashtable key */
	MemoryContext fn_cxt;

	Oid			fn_rettype;
	int			fn_rettyplen;
	bool		fn_retbyval;
	FmgrInfo	fn_retinput;
	Oid			fn_rettypioparam;
	bool		fn_retistuple;
	bool		fn_retset;
	bool		fn_readonly;

	int			fn_nargs;
	int			fn_argvarnos[FUNC_MAX_ARGS];
	int			out_param_varno;
	int			found_varno;
	int			new_varno;
	int			old_varno;
	int			tg_name_varno;
	int			tg_when_varno;
	int			tg_level_varno;
	int			tg_op_varno;
	int			tg_relid_varno;
	int			tg_relname_varno;
	int			tg_table_name_varno;
	int			tg_table_schema_varno;
	int			tg_nargs_varno;

	int			ndatums;
	PLpgSQL_datum **datums;
	PLpgSQL_stmt_block *action;

	unsigned long use_count;
} PLpgSQL_function;


typedef struct
{								/* Runtime execution data	*/
	Datum		retval;
	bool		retisnull;
	Oid			rettype;		/* type of current retval */

	Oid			fn_rettype;		/* info about declared function rettype */
	bool		retistuple;
	bool		retisset;

	bool		readonly_func;

	TupleDesc	rettupdesc;
	char	   *exitlabel;		/* the "target" label of the current EXIT or
								 * CONTINUE stmt, if any */

	Tuplestorestate *tuple_store;		/* SRFs accumulate results here */
	MemoryContext tuple_store_cxt;
	ReturnSetInfo *rsi;

	int			trig_nargs;
	Datum	   *trig_argv;

	int			found_varno;
	int			ndatums;
	PLpgSQL_datum **datums;

	/* temporary state for results from evaluation of query or expr */
	SPITupleTable *eval_tuptable;
	uint32		eval_processed;
	Oid			eval_lastoid;
	ExprContext *eval_econtext; /* for executing simple expressions */
	EState	   *eval_estate;	/* EState containing eval_econtext */
	long int	eval_estate_simple_id;	/* ID for eval_estate */

	/* status information for error context reporting */
	PLpgSQL_function *err_func; /* current func */
	PLpgSQL_stmt *err_stmt;		/* current stmt */
	const char *err_text;		/* additional state info */
	void	   *plugin_info;	/* reserved for use by optional plugin */
} PLpgSQL_execstate;


/*
 * A PLpgSQL_plugin structure represents an instrumentation plugin.
 * To instrument PL/pgSQL, a plugin library must access the rendezvous
 * variable "PLpgSQL_plugin" and set it to point to a PLpgSQL_plugin struct.
 * Typically the struct could just be static data in the plugin library.
 * We expect that a plugin would do this at library load time (_PG_init()).
 * It must also be careful to set the rendezvous variable back to NULL
 * if it is unloaded (_PG_fini()).
 *
 * This structure is basically a collection of function pointers --- at
 * various interesting points in pl_exec.c, we call these functions
 * (if the pointers are non-NULL) to give the plugin a chance to watch
 * what we are doing.
 *
 *	func_setup is called when we start a function, before we've initialized
 *	the local variables defined by the function.
 *
 *	func_beg is called when we start a function, after we've initialized
 *	the local variables.
 *
 *	func_end is called at the end of a function.
 *
 *	stmt_beg and stmt_end are called before and after (respectively) each
 *	statement.
 *
 * Also, immediately before any call to func_setup, PL/pgSQL fills in the
 * error_callback and assign_expr fields with pointers to its own
 * plpgsql_exec_error_callback and exec_assign_expr functions.	This is
 * a somewhat ad-hoc expedient to simplify life for debugger plugins.
 */

typedef struct
{
	/* Function pointers set up by the plugin */
	void		(*func_setup) (PLpgSQL_execstate *estate, PLpgSQL_function *func);
	void		(*func_beg) (PLpgSQL_execstate *estate, PLpgSQL_function *func);
	void		(*func_end) (PLpgSQL_execstate *estate, PLpgSQL_function *func);
	void		(*stmt_beg) (PLpgSQL_execstate *estate, PLpgSQL_stmt *stmt);
	void		(*stmt_end) (PLpgSQL_execstate *estate, PLpgSQL_stmt *stmt);

	/* Function pointers set by PL/pgSQL itself */
	void		(*error_callback) (void *arg);
	void		(*assign_expr) (PLpgSQL_execstate *estate, PLpgSQL_datum *target,
											PLpgSQL_expr *expr);
} PLpgSQL_plugin;


/**********************************************************************
 * Global variable declarations
 **********************************************************************/

extern bool plpgsql_DumpExecTree;
extern bool plpgsql_SpaceScanned;
extern int	plpgsql_nDatums;
extern PLpgSQL_datum **plpgsql_Datums;

extern int	plpgsql_error_lineno;
extern char *plpgsql_error_funcname;

/* linkage to the real yytext variable */
extern char *plpgsql_base_yytext;

#define yytext plpgsql_base_yytext

extern PLpgSQL_function *plpgsql_curr_compile;
extern bool plpgsql_check_syntax;
extern MemoryContext compile_tmp_cxt;

extern PLpgSQL_plugin **plugin_ptr;

/**********************************************************************
 * Function declarations
 **********************************************************************/

/* ----------
 * Functions in pl_comp.c
 * ----------
 */
extern PLpgSQL_function *plpgsql_compile(FunctionCallInfo fcinfo,
				bool forValidator);
extern int	plpgsql_parse_word(const char *word);
extern int	plpgsql_parse_dblword(const char *word);
extern int	plpgsql_parse_tripword(const char *word);
extern int	plpgsql_parse_wordtype(char *word);
extern int	plpgsql_parse_dblwordtype(char *word);
extern int	plpgsql_parse_tripwordtype(char *word);
extern int	plpgsql_parse_wordrowtype(char *word);
extern int	plpgsql_parse_dblwordrowtype(char *word);
extern PLpgSQL_type *plpgsql_parse_datatype(const char *string);
extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod);
extern PLpgSQL_variable *plpgsql_build_variable(const char *refname, int lineno,
					   PLpgSQL_type *dtype,
					   bool add2namespace);
extern PLpgSQL_condition *plpgsql_parse_err_condition(char *condname);
extern void plpgsql_adddatum(PLpgSQL_datum *new);
extern int	plpgsql_add_initdatums(int **varnos);
extern void plpgsql_HashTableInit(void);
extern void plpgsql_compile_error_callback(void *arg);

/* ----------
 * Functions in pl_handler.c
 * ----------
 */
extern void _PG_init(void);
extern Datum plpgsql_call_handler(PG_FUNCTION_ARGS);
extern Datum plpgsql_validator(PG_FUNCTION_ARGS);

/* ----------
 * Functions in pl_exec.c
 * ----------
 */
extern Datum plpgsql_exec_function(PLpgSQL_function *func,
					  FunctionCallInfo fcinfo);
extern HeapTuple plpgsql_exec_trigger(PLpgSQL_function *func,
					 TriggerData *trigdata);
extern void plpgsql_xact_cb(XactEvent event, void *arg);
extern void plpgsql_subxact_cb(SubXactEvent event, SubTransactionId mySubid,
				   SubTransactionId parentSubid, void *arg);

/* ----------
 * Functions for the dynamic string handling in pl_funcs.c
 * ----------
 */
extern void plpgsql_dstring_init(PLpgSQL_dstring *ds);
extern void plpgsql_dstring_free(PLpgSQL_dstring *ds);
extern void plpgsql_dstring_append(PLpgSQL_dstring *ds, const char *str);
extern void plpgsql_dstring_append_char(PLpgSQL_dstring *ds, char c);
extern char *plpgsql_dstring_get(PLpgSQL_dstring *ds);

/* ----------
 * Functions for namestack handling in pl_funcs.c
 * ----------
 */
extern void plpgsql_ns_init(void);
extern bool plpgsql_ns_setlocal(bool flag);
extern void plpgsql_ns_push(const char *label);
extern void plpgsql_ns_pop(void);
extern void plpgsql_ns_additem(int itemtype, int itemno, const char *name);
extern PLpgSQL_nsitem *plpgsql_ns_lookup(const char *name1, const char *name2,
										 const char *name3, int *names_used);
extern PLpgSQL_nsitem *plpgsql_ns_lookup_label(const char *name);
extern void plpgsql_ns_rename(char *oldname, char *newname);

/* ----------
 * Other functions in pl_funcs.c
 * ----------
 */
extern void plpgsql_convert_ident(const char *s, char **output, int numidents);
extern const char *plpgsql_stmt_typename(PLpgSQL_stmt *stmt);
extern void plpgsql_dumptree(PLpgSQL_function *func);

/* ----------
 * Externs in gram.y and scan.l
 * ----------
 */
extern PLpgSQL_expr *plpgsql_read_expression(int until, const char *expected);
extern int	plpgsql_yyparse(void);
extern int	plpgsql_base_yylex(void);
extern int	plpgsql_yylex(void);
extern void plpgsql_push_back_token(int token);
extern void plpgsql_yyerror(const char *message);
extern int	plpgsql_scanner_lineno(void);
extern void plpgsql_scanner_init(const char *str, int functype);
extern void plpgsql_scanner_finish(void);
extern char *plpgsql_get_string_value(void);

#endif   /* PLPGSQL_H */