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/*-------------------------------------------------------------------------
*
* libpq-int.h--
* This file contains internal definitions meant to be used only by
* the frontend libpq library, not by applications that call it.
*
* An application can include this file if it wants to bypass the
* official API defined by libpq-fe.h, but code that does so is much
* more likely to break across PostgreSQL releases than code that uses
* only the official API.
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: libpq-int.h,v 1.4 1998/10/01 01:40:25 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef LIBPQ_INT_H
#define LIBPQ_INT_H
/* We assume libpq-fe.h has already been included. */
/* ----------------
* include stuff common to fe and be
* ----------------
*/
#include "libpq/pqcomm.h"
#include "lib/dllist.h"
/* libpq supports this version of the frontend/backend protocol.
*
* NB: we used to use PG_PROTOCOL_LATEST from the backend pqcomm.h file,
* but that's not really the right thing: just recompiling libpq
* against a more recent backend isn't going to magically update it
* for most sorts of protocol changes. So, when you change libpq
* to support a different protocol revision, you have to change this
* constant too. PG_PROTOCOL_EARLIEST and PG_PROTOCOL_LATEST in
* pqcomm.h describe what the backend knows, not what libpq knows.
*/
#define PG_PROTOCOL_LIBPQ PG_PROTOCOL(2,0)
/*
* POSTGRES backend dependent Constants.
*/
/* ERROR_MSG_LENGTH should really be the same as ELOG_MAXLEN in utils/elog.h*/
#define ERROR_MSG_LENGTH 4096
#define CMDSTATUS_LEN 40
/* PGresult and the subsidiary types PGresAttDesc, PGresAttValue
* represent the result of a query (or more precisely, of a single SQL
* command --- a query string given to PQexec can contain multiple commands).
* Note we assume that a single command can return at most one tuple group,
* hence there is no need for multiple descriptor sets.
*/
typedef struct pgresAttDesc
{
char *name; /* type name */
Oid typid; /* type id */
int typlen; /* type size */
int atttypmod; /* type-specific modifier info */
} PGresAttDesc;
/* use char* for Attribute values,
ASCII tuples are guaranteed to be null-terminated
For binary tuples, the first four bytes of the value is the size,
and the bytes afterwards are the value. The binary value is
not guaranteed to be null-terminated. In fact, it can have embedded nulls
*/
#define NULL_LEN (-1) /* pg_result len for NULL value */
typedef struct pgresAttValue
{
int len; /* length in bytes of the value */
char *value; /* actual value */
} PGresAttValue;
struct pg_result
{
int ntups;
int numAttributes;
PGresAttDesc *attDescs;
PGresAttValue **tuples; /* each PGresTuple is an array of
* PGresAttValue's */
int tupArrSize; /* size of tuples array allocated */
ExecStatusType resultStatus;
char cmdStatus[CMDSTATUS_LEN]; /* cmd status from the
* last insert query */
int binary; /* binary tuple values if binary == 1,
* otherwise ASCII */
/* NOTE: conn is kept here only for the temporary convenience of
* applications that rely on it being here. It will go away in a
* future release, because relying on it is a bad idea --- what if
* the PGresult has outlived the PGconn? About the only thing it was
* really good for was fetching the errorMessage, and we stash that
* here now anyway.
*/
PGconn *conn; /* connection we did the query on */
char *errMsg; /* error message, or NULL if no error */
};
/* PGAsyncStatusType defines the state of the query-execution state machine */
typedef enum
{
PGASYNC_IDLE, /* nothing's happening, dude */
PGASYNC_BUSY, /* query in progress */
PGASYNC_READY, /* result ready for PQgetResult */
PGASYNC_COPY_IN, /* Copy In data transfer in progress */
PGASYNC_COPY_OUT /* Copy Out data transfer in progress */
} PGAsyncStatusType;
/* large-object-access data ... allocated only if large-object code is used. */
typedef struct pgLobjfuncs
{
Oid fn_lo_open; /* OID of backend function lo_open */
Oid fn_lo_close;/* OID of backend function lo_close */
Oid fn_lo_creat;/* OID of backend function lo_creat */
Oid fn_lo_unlink; /* OID of backend function
* lo_unlink */
Oid fn_lo_lseek;/* OID of backend function lo_lseek */
Oid fn_lo_tell; /* OID of backend function lo_tell */
Oid fn_lo_read; /* OID of backend function LOread */
Oid fn_lo_write;/* OID of backend function LOwrite */
} PGlobjfuncs;
/* PGconn stores all the state data associated with a single connection
* to a backend.
*/
struct pg_conn
{
/* Saved values of connection options */
char *pghost; /* the machine on which the server is
* running */
char *pgport; /* the server's communication port */
char *pgtty; /* tty on which the backend messages is
* displayed (NOT ACTUALLY USED???) */
char *pgoptions; /* options to start the backend with */
char *dbName; /* database name */
char *pguser; /* Postgres username and password, if any */
char *pgpass;
/* Optional file to write trace info to */
FILE *Pfdebug;
/* Callback procedure for notice/error message processing */
PQnoticeProcessor noticeHook;
void *noticeArg;
/* Status indicators */
ConnStatusType status;
PGAsyncStatusType asyncStatus;
Dllist *notifyList; /* Notify msgs not yet handed to application */
/* Connection data */
int sock; /* Unix FD for socket, -1 if not connected */
SockAddr laddr; /* Local address */
SockAddr raddr; /* Remote address */
int raddr_len; /* Length of remote address */
/* Miscellaneous stuff */
int be_pid; /* PID of backend --- needed for cancels */
int be_key; /* key of backend --- needed for cancels */
char salt[2]; /* password salt received from backend */
PGlobjfuncs *lobjfuncs; /* private state for large-object access fns */
/* Buffer for data received from backend and not yet processed */
char *inBuffer; /* currently allocated buffer */
int inBufSize; /* allocated size of buffer */
int inStart; /* offset to first unconsumed data in buffer */
int inCursor; /* next byte to tentatively consume */
int inEnd; /* offset to first position after avail data */
/* Buffer for data not yet sent to backend */
char *outBuffer; /* currently allocated buffer */
int outBufSize; /* allocated size of buffer */
int outCount; /* number of chars waiting in buffer */
/* Status for asynchronous result construction */
PGresult *result; /* result being constructed */
PGresAttValue *curTuple; /* tuple currently being read */
/* Message space. Placed last for code-size reasons. */
char errorMessage[ERROR_MSG_LENGTH];
};
/* ----------------
* Internal functions of libpq
* Functions declared here need to be visible across files of libpq,
* but are not intended to be called by applications. We use the
* convention "pqXXX" for internal functions, vs. the "PQxxx" names
* used for application-visible routines.
* ----------------
*/
/* === in fe-connect.c === */
extern int pqPacketSend(PGconn *conn, const char *buf, size_t len);
/* === in fe-exec.c === */
extern void pqSetResultError(PGresult *res, const char *msg);
extern void pqClearAsyncResult(PGconn *conn);
/* === in fe-misc.c === */
/*
* "Get" and "Put" routines return 0 if successful, EOF if not. Note that
* for Get, EOF merely means the buffer is exhausted, not that there is
* necessarily any error.
*/
extern int pqGetc(char *result, PGconn *conn);
extern int pqGets(char *s, int maxlen, PGconn *conn);
extern int pqPuts(const char *s, PGconn *conn);
extern int pqGetnchar(char *s, int len, PGconn *conn);
extern int pqPutnchar(const char *s, int len, PGconn *conn);
extern int pqGetInt(int *result, int bytes, PGconn *conn);
extern int pqPutInt(int value, int bytes, PGconn *conn);
extern int pqReadData(PGconn *conn);
extern int pqFlush(PGconn *conn);
extern int pqWait(int forRead, int forWrite, PGconn *conn);
/* max length of message to send */
#define MAX_MESSAGE_LEN 8193
/* maximum number of fields in a tuple */
#define MAX_FIELDS 512
/* bits in a byte */
#define BYTELEN 8
/* fall back options if they are not specified by arguments or defined
by environment variables */
#define DefaultHost "localhost"
#define DefaultTty ""
#define DefaultOption ""
#define DefaultAuthtype ""
#define DefaultPassword ""
/* supply an implementation of strerror() macro if system doesn't have it */
#ifndef strerror
#if defined(sun) && defined(sparc) && !defined(__SVR4)
extern char *sys_errlist[];
#define strerror(A) (sys_errlist[(A)])
#endif /* sunos4 */
#endif /* !strerror */
#endif /* LIBPQ_INT_H */
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