@ -12,7 +12,7 @@
* Portions Copyright ( c ) 1996 - 2002 , PostgreSQL Global Development Group
* Portions Copyright ( c ) 1994 , Regents of the University of California
*
* $ Id : libpq - int . h , v 1.70 2003 / 05 / 08 18 : 33 : 39 tgl Exp $
* $ Id : libpq - int . h , v 1.71 2003 / 06 / 08 17 : 43 : 00 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -35,6 +35,7 @@ typedef int ssize_t; /* ssize_t doesn't exist in VC (atleast
# include "postgres_fe.h"
/* include stuff common to fe and be */
# include "getaddrinfo.h"
# include "libpq/pqcomm.h"
# include "lib/dllist.h"
/* include stuff found in fe only */
@ -45,23 +46,9 @@ typedef int ssize_t; /* ssize_t doesn't exist in VC (atleast
# include <openssl/err.h>
# endif
/* 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(3,0)
/*
* POSTGRES backend dependent Constants .
*/
# define PQERRORMSG_LENGTH 1024
# define CMDSTATUS_LEN 40
@ -96,20 +83,22 @@ typedef struct pgresAttDesc
int atttypmod ; /* type-specific modifier info */
} PGresAttDesc ;
/* Data for a single attribute of a single tuple */
/* We use char* for Attribute values.
The value pointer always points to a null - terminated area ; we add a
null ( zero ) byte after whatever the backend sends us . This is only
particularly useful for text tuples . . . with a binary value , the
value might have embedded nulls , so the application can ' t use C string
operators on it . But we add a null anyway for consistency .
Note that the value itself does not contain a length word .
A NULL attribute is a special case in two ways : its len field is NULL_LEN
and its value field points to null_field in the owning PGresult . All the
NULL attributes in a query result point to the same place ( there ' s no need
to store a null string separately for each one ) .
/*
* Data for a single attribute of a single tuple
*
* We use char * for Attribute values .
*
* The value pointer always points to a null - terminated area ; we add a
* null ( zero ) byte after whatever the backend sends us . This is only
* particularly useful for text tuples . . . with a binary value , the
* value might have embedded nulls , so the application can ' t use C string
* operators on it . But we add a null anyway for consistency .
* Note that the value itself does not contain a length word .
*
* A NULL attribute is a special case in two ways : its len field is NULL_LEN
* and its value field points to null_field in the owning PGresult . All the
* NULL attributes in a query result point to the same place ( there ' s no need
* to store a null string separately for each one ) .
*/
# define NULL_LEN (-1) /* pg_result len for NULL value */
@ -135,15 +124,6 @@ struct pg_result
int binary ; /* binary tuple values if binary == 1,
* otherwise text */
/*
* The conn link in PGresult is no longer used by any libpq code . It
* should be removed entirely , because it could be a dangling link
* ( the application could keep the PGresult around longer than it
* keeps the PGconn ! ) But there may be apps out there that depend on
* it , so we will leave it here at least for a release or so .
*/
PGconn * xconn ; /* connection we did the query on, if any */
/*
* These fields are copied from the originating PGconn , so that
* operations on the PGresult don ' t have to reference the PGconn .
@ -194,6 +174,35 @@ typedef enum
PGASYNC_COPY_OUT /* Copy Out data transfer in progress */
} PGAsyncStatusType ;
/* PGSetenvStatusType defines the state of the PQSetenv state machine */
/* (this is used only for 2.0-protocol connections) */
typedef enum
{
SETENV_STATE_OPTION_SEND , /* About to send an Environment Option */
SETENV_STATE_OPTION_WAIT , /* Waiting for above send to complete */
SETENV_STATE_QUERY1_SEND , /* About to send a status query */
SETENV_STATE_QUERY1_WAIT , /* Waiting for query to complete */
SETENV_STATE_QUERY2_SEND , /* About to send a status query */
SETENV_STATE_QUERY2_WAIT , /* Waiting for query to complete */
SETENV_STATE_IDLE
} PGSetenvStatusType ;
/* Typedef for the EnvironmentOptions[] array */
typedef struct PQEnvironmentOption
{
const char * envName , /* name of an environment variable */
* pgName ; /* name of corresponding SET variable */
} PQEnvironmentOption ;
/* Typedef for parameter-status list entries */
typedef struct pgParameterStatus
{
struct pgParameterStatus * next ; /* list link */
char * name ; /* parameter name */
char * value ; /* parameter value */
/* Note: name and value are stored in same malloc block as struct is */
} pgParameterStatus ;
/* large-object-access data ... allocated only if large-object code is used. */
typedef struct pgLobjfuncs
{
@ -207,7 +216,8 @@ typedef struct pgLobjfuncs
Oid fn_lo_write ; /* OID of backend function LOwrite */
} PGlobjfuncs ;
/* PGconn stores all the state data associated with a single connection
/*
* PGconn stores all the state data associated with a single connection
* to a backend .
*/
struct pg_conn
@ -254,12 +264,21 @@ struct pg_conn
SockAddr laddr ; /* Local address */
SockAddr raddr ; /* Remote address */
int raddr_len ; /* Length of remote address */
ProtocolVersion pversion ; /* FE/BE protocol version in use */
char sversion [ 8 ] ; /* The first few bytes of server version */
/* Transient state needed while establishing connection */
struct addrinfo * addrlist ; /* list of possible backend addresses */
struct addrinfo * addr_cur ; /* the one currently being tried */
PGSetenvStatusType setenv_state ; /* for 2.0 protocol only */
const PQEnvironmentOption * next_eo ;
/* Miscellaneous stuff */
int be_pid ; /* PID of backend --- needed for cancels */
int be_key ; /* key of backend --- needed for cancels */
char md5Salt [ 4 ] ; /* password salt received from backend */
char cryptSalt [ 2 ] ; /* password salt received from backend */
pgParameterStatus * pstatus ; /* ParameterStatus data */
int client_encoding ; /* encoding id */
PGlobjfuncs * lobjfuncs ; /* private state for large-object access
* fns */
@ -279,7 +298,8 @@ struct pg_conn
int outCount ; /* number of chars waiting in buffer */
/* State for constructing messages in outBuffer */
int outMsgStart ; /* offset to msg start (length word) */
int outMsgStart ; /* offset to msg start (length word);
* if - 1 , msg has no length word */
int outMsgEnd ; /* offset to msg end (so far) */
/* Status for asynchronous result construction */
@ -324,10 +344,46 @@ extern int pqPacketSend(PGconn *conn, char pack_type,
/* === in fe-exec.c === */
extern void pqSetResultError ( PGresult * res , const char * msg ) ;
extern void pqCatenateResultError ( PGresult * res , const char * msg ) ;
extern void * pqResultAlloc ( PGresult * res , size_t nBytes , bool isBinary ) ;
extern char * pqResultStrdup ( PGresult * res , const char * str ) ;
extern void pqClearAsyncResult ( PGconn * conn ) ;
extern int pqGetErrorNotice ( PGconn * conn , bool isError ) ;
extern void pqSaveErrorResult ( PGconn * conn ) ;
extern PGresult * pqPrepareAsyncResult ( PGconn * conn ) ;
extern int pqAddTuple ( PGresult * res , PGresAttValue * tup ) ;
extern void pqSaveParameterStatus ( PGconn * conn , const char * name ,
const char * value ) ;
extern const char * pqGetParameterStatus ( PGconn * conn , const char * name ) ;
extern void pqHandleSendFailure ( PGconn * conn ) ;
/* === in fe-protocol2.c === */
extern PostgresPollingStatusType pqSetenvPoll ( PGconn * conn ) ;
extern char * pqBuildStartupPacket2 ( PGconn * conn , int * packetlen ,
const PQEnvironmentOption * options ) ;
extern void pqParseInput2 ( PGconn * conn ) ;
extern int pqGetline2 ( PGconn * conn , char * s , int maxlen ) ;
extern int pqGetlineAsync2 ( PGconn * conn , char * buffer , int bufsize ) ;
extern int pqEndcopy2 ( PGconn * conn ) ;
extern PGresult * pqFunctionCall2 ( PGconn * conn , Oid fnid ,
int * result_buf , int * actual_result_len ,
int result_is_int ,
const PQArgBlock * args , int nargs ) ;
/* === in fe-protocol3.c === */
extern char * pqBuildStartupPacket3 ( PGconn * conn , int * packetlen ,
const PQEnvironmentOption * options ) ;
extern void pqParseInput3 ( PGconn * conn ) ;
extern int pqGetErrorNotice3 ( PGconn * conn , bool isError ) ;
extern int pqGetline3 ( PGconn * conn , char * s , int maxlen ) ;
extern int pqGetlineAsync3 ( PGconn * conn , char * buffer , int bufsize ) ;
extern int pqEndcopy3 ( PGconn * conn ) ;
extern PGresult * pqFunctionCall3 ( PGconn * conn , Oid fnid ,
int * result_buf , int * actual_result_len ,
int result_is_int ,
const PQArgBlock * args , int nargs ) ;
/* === in fe-misc.c === */
@ -345,7 +401,7 @@ extern int pqGetnchar(char *s, size_t len, PGconn *conn);
extern int pqPutnchar ( const char * s , size_t len , PGconn * conn ) ;
extern int pqGetInt ( int * result , size_t bytes , PGconn * conn ) ;
extern int pqPutInt ( int value , size_t bytes , PGconn * conn ) ;
extern int pqPutMsgStart ( char msg_type , PGconn * conn ) ;
extern int pqPutMsgStart ( char msg_type , bool force_len , PGconn * conn ) ;
extern int pqPutMsgEnd ( PGconn * conn ) ;
extern int pqReadData ( PGconn * conn ) ;
extern int pqFlush ( PGconn * conn ) ;
@ -359,21 +415,14 @@ extern int pqWriteReady(PGconn *conn);
extern int pqsecure_initialize ( PGconn * ) ;
extern void pqsecure_destroy ( void ) ;
extern int pqsecure_open_client ( PGconn * ) ;
extern PostgresPollingStatusType pqsecure_open_client ( PGconn * ) ;
extern void pqsecure_close ( PGconn * ) ;
extern ssize_t pqsecure_read ( PGconn * , void * ptr , size_t len ) ;
extern ssize_t pqsecure_write ( PGconn * , const void * ptr , size_t len ) ;
/* 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 ""
/* Note: PGDONOTICE macro will work if applied to either PGconn or PGresult */
# define PGDONOTICE(conn,message) \
( ( * ( conn ) - > noticeHook ) ( ( conn ) - > noticeArg , ( message ) ) )
/*
* this is so that we can check is a connection is non - blocking internally
Tom Lane
23 years ago