fe-exec.c

/*-------------------------------------------------------------------------
 *
 * fe-exec.c
 *	  functions related to sending a query down to the backend
 *
 * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-exec.c,v 1.107 2001/08/17 15:11:15 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#include "postgres_fe.h"

#include <errno.h>
#include <ctype.h>
#include <fcntl.h>

#include "libpq-fe.h"
#include "libpq-int.h"

#ifdef WIN32
#include "win32.h"
#else
#include <unistd.h>
#endif

/* keep this in same order as ExecStatusType in libpq-fe.h */
char	   *const pgresStatus[] = {
	"PGRES_EMPTY_QUERY",
	"PGRES_COMMAND_OK",
	"PGRES_TUPLES_OK",
	"PGRES_COPY_OUT",
	"PGRES_COPY_IN",
	"PGRES_BAD_RESPONSE",
	"PGRES_NONFATAL_ERROR",
	"PGRES_FATAL_ERROR"
};


/* Note: DONOTICE macro will work if applied to either PGconn or PGresult */
#define DONOTICE(conn,message) \
	((*(conn)->noticeHook) ((conn)->noticeArg, (message)))


static void pqCatenateResultError(PGresult *res, const char *msg);
static void saveErrorResult(PGconn *conn);
static PGresult *prepareAsyncResult(PGconn *conn);
static int	addTuple(PGresult *res, PGresAttValue * tup);
static void parseInput(PGconn *conn);
static void handleSendFailure(PGconn *conn);
static int	getRowDescriptions(PGconn *conn);
static int	getAnotherTuple(PGconn *conn, int binary);
static int	getNotify(PGconn *conn);
static int	getNotice(PGconn *conn);


/* ----------------
 * Space management for PGresult.
 *
 * Formerly, libpq did a separate malloc() for each field of each tuple
 * returned by a query.  This was remarkably expensive --- malloc/free
 * consumed a sizable part of the application's runtime.  And there is
 * no real need to keep track of the fields separately, since they will
 * all be freed together when the PGresult is released.  So now, we grab
 * large blocks of storage from malloc and allocate space for query data
 * within these blocks, using a trivially simple allocator.  This reduces
 * the number of malloc/free calls dramatically, and it also avoids