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Postgres FD Implementation
Commit 3ab5b1f1 authored by Bruce Momjian's avatar Bruce Momjian
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This patch (against the current CVS sources) adds to libpq the functions 

PQconnectStart
PQconnectPoll
PQresetStart
PQresetPoll
PQsetenvStart
PQsetenvPoll
PQsetenvAbort

and brings into the published interface

PQsetenv.

The first four are asynchronous analogues of PQconnectdb and PQreset -
they allow an application to connect to the DB without blocking on
remote I/O.

The PQsetenv functions perform an environment negotiation with the
server.

Internal to libpq, pqReadReady and pqWriteReady have been made available
across the library (they were previously static functions inside
fe-misc.c).  A lot of internal rearrangement has been necessary to
support these changes.

The API documentation has been updated also.

Caveats:

  o  The Windows code does not default to using non-blocking sockets,
since I have no documentation: Define WIN32_NON_BLOCKING_CONNECTIONS to
do that.

  o  The SSL code still blocks.


Ewan Mellor.
parent d264b53d
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Showing with 1486 additions and 271 deletions
doc/src/sgml/libpq.sgml
View file @ 3ab5b1f1
......@@ -57,14 +57,13 @@ header file <FileName>libpq-fe.h</FileName> and must link with the
<synopsis>
PGconn *PQconnectdb(const char *conninfo)
</synopsis>
This routine opens a new database connection using the parameters
taken from the string <literal>conninfo</literal>. Unlike PQsetdbLogin()
below, the parameter set
can be extended without changing the function signature, so use
of this routine is prefered for application programming. The passed
string can be empty to use all default
parameters, or it can contain one or more parameter settings
separated by whitespace.
This routine opens a new database connection using the parameters taken
from the string <literal>conninfo</literal>. Unlike PQsetdbLogin() below,
the parameter set can be extended without changing the function signature,
so use either of this routine or the non-blocking analogues PQconnectStart
/ PQconnectPoll is prefered for application programming. The passed string
can be empty to use all default parameters, or it can contain one or more
parameter settings separated by whitespace.
</Para>
<Para>
Each parameter setting is in the form <literal>keyword = value</literal>.
......@@ -80,8 +79,38 @@ PGconn *PQconnectdb(const char *conninfo)
<term><literal>host</literal></term>
<ListItem>
<Para>
Host to connect to. If a non-zero-length string is specified, TCP/IP communication is used.
Without a host name, libpq will connect using a local Unix domain socket.
Name of host to connect to. If a non-zero-length string is specified, TCP/IP
communication is used. Using this parameter causes a hostname look-up.
See hostaddr.
</Para>
</ListItem>
</VarListEntry>
<VarListEntry>
<term><literal>hostaddr</literal></term>
<ListItem>
<Para>
IP address of host to connect to. This should be in standard
numbers-and-dots form, as used by the BSD functions inet_aton et al. If
a non-zero-length string is specified, TCP/IP communication is used.
</Para>
<Para>
Using hostaddr instead of host allows the application to avoid a host
name look-up, which may be important in applications with time
constraints. However, Kerberos authentication requires the host
name. The following therefore applies. If host is specified without
hostaddr, a hostname look-up is forced. If hostaddr is specified without
host, the value for hostaddr gives the remote address; if Kerberos is
used, this causes a reverse name query. If both host and hostaddr are
specified, the value for hostaddr gives the remote address; the value
for host is ignored, unless Kerberos is used, in which case that value
is used for Kerberos authentication. Note that authentication is likely
to fail if libpq is passed a host name which is not the name of the
machine at hostaddr.
</Para>
<Para>
Without both a host name and host address, libpq will connect using a
local Unix domain socket.
</Para>
</ListItem>
</VarListEntry>
......@@ -149,6 +178,9 @@ PGconn *PQconnectdb(const char *conninfo)
The return value is a pointer to an abstract struct
representing the connection to the backend.
</Para>
<Para>
This function is not thread-safe.
</Para>
</ListItem>
<ListItem>
......@@ -167,6 +199,9 @@ PGconn *PQsetdbLogin(const char *pghost,
This is the predecessor of <function>PQconnectdb</function> with a fixed number
of parameters but the same functionality.
</Para>
<Para>
This function is not thread-safe.
</Para>
</ListItem>
<ListItem>
......@@ -185,6 +220,173 @@ PGconn *PQsetdb(char *pghost,
</Para>
</ListItem>
<ListItem>
<Para>
<Function>PQconnectStart</Function>
<Function>PQconnectPoll</Function>
Make a connection to the database server in a non-blocking manner.
<synopsis>
PGconn *PQconnectStart(const char *conninfo)
</synopsis>
<synopsis>
PostgresPollingStatusType *PQconnectPoll(PQconn *conn)
</synopsis>
These two routines are used to open a connection to a database server such
that your application's thread of execution is not blocked on remote I/O
whilst doing so.
</Para>
<Para>
The database connection is made using the parameters taken from the string
<literal>conninfo</literal>, passed to PQconnectStart. This string is in
the same format as described above for PQconnectdb.
</Para>
<Para>
Neither PQconnectStart nor PQconnectPoll will block, as long as a number of
restrictions are met:
<ItemizedList>
<ListItem>
<Para>
The hostaddr and host parameters are used appropriately to ensure that
name and reverse name queries are not made. See the documentation of
these parameters under PQconnectdb above for details.
</Para>
</ListItem>
<ListItem>
<Para>
If you call PQtrace, ensure that the stream object into which you trace
will not block.
</Para>
</ListItem>
<ListItem>
<Para>
You ensure for yourself that the socket is in the appropriate state
before calling PQconnectPoll, as described below.
</Para>
</ListItem>
</ItemizedList>
</Para>
<Para>
To begin, call conn=PQconnectStart("&lt;connection_info_string&gt;"). If
conn is NULL, then libpq has been unable to allocate a new PGconn
structure. Otherwise, a valid PGconn pointer is returned (though not yet
representing a valid connection to the database). On return from
PQconnectStart, call status=PQstatus(conn). If status equals
CONNECTION_BAD, PQconnectStart has failed.
</Para>
<Para>
If PQconnectStart succeeds, the next stage is to poll libpq so that it may
proceed with the connection sequence. Loop thus: Consider a connection
'inactive' by default. If PQconnectPoll last returned PGRES_POLLING_ACTIVE,
consider it 'active' instead. If PQconnectPoll(conn) last returned
PGRES_POLLING_READING, perform a select for reading on PQsocket(conn). If
it last returned PGRES_POLLING_WRITING, perform a select for writing on
PQsocket(conn). If you have yet to call PQconnectPoll, i.e. after the call
to PQconnectStart, behave as if it last returned PGRES_POLLING_WRITING. If
the select shows that the socket is ready, consider it 'active'. If it has
been decided that this connection is 'active', call PQconnectPoll(conn)
again. If this call returns PGRES_POLLING_FAILED, the connection procedure
has failed. If this call returns PGRES_POLLING_OK, the connection has been
successfully made.
</Para>
<Para>
Note that the use of select() to ensure that the socket is ready is merely
a (likely) example; those with other facilities available, such as a
poll() call, may of course use that instead.
</Para>
<Para>
At any time during connection, the status of the connection may be
checked, by calling PQstatus. If this is CONNECTION_BAD, then the
connection procedure has failed; if this is CONNECTION_OK, then the
connection is ready. Either of these states should be equally detectable
from the return value of PQconnectPoll, as above. Other states may be
shown during (and only during) an asynchronous connection procedure. These
indicate the current stage of the connection procedure, and may be useful
to provide feedback to the user for example. These statuses may include:
<ItemizedList>
<ListItem>
<Para>
CONNECTION_STARTED: Waiting for connection to be made.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_MADE: Connection OK; waiting to send.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_AWAITING_RESPONSE: Waiting for a response from the backend.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_AUTH_RESPONSE: Got an authentication response; about to deal
with it.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_ERROR_RESPONSE: Got an error response; about to deal with it.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_AUTH_OK: Received authentication; waiting for ReadyForQuery etc.
</Para>
</ListItem>
<ListItem>
<Para>
CONNECTION_SETENV: Negotiating environment.
</Para>
</ListItem>
</ItemizedList>
Note that, although these constants will remain (in order to maintain
compatibility) an application should never rely upon these appearing in a
particular order, or at all, or on the status always being one of these
documented values. An application may do something like this:
<ProgramListing>
switch(PQstatus(conn))
{
case CONNECTION_STARTED:
feedback = "Connecting...";
break;
case CONNECTION_MADE:
feedback = "Connected to server...";
break;
.
.
.
default:
feedback = "Connecting...";
}
</ProgramListing>
</Para>
<Para>
Note that if PQconnectStart returns a non-NULL pointer, you must call
PQfinish upon that, when you are finished with it, in order to dispose of
the structure and any associated memory blocks. This must be done even if a
call to PQconnectStart or PQconnectPoll failed.
</Para>
<Para>
PQconnectPoll will currently block if libpq is compiled with USE_SSL
defined. This restriction may be removed in the future.
</Para>
<Para>
PQconnectPoll will currently block under Windows, unless libpq is compiled
with WIN32_NON_BLOCKING_CONNECTIONS defined. This code has not yet been
tested under Windows, and so it is currently off by default. This may be
changed in the future.
</Para>
<Para>
These functions are not thread-safe.
</Para>
</ListItem>
<ListItem>
<Para>
<Function>PQconndefaults</Function> Returns the default connection options.
......@@ -215,6 +417,9 @@ struct PQconninfoOption
will depend on environment variables and other context.
Callers must treat the connection options data as read-only.
</Para>
<Para>
This function is not thread-safe.
</Para>
</ListItem>
<ListItem>
......@@ -247,6 +452,31 @@ void PQreset(PGconn *conn)
</Para>
</ListItem>
<ListItem>
<Para>
<Function>PQresetStart</Function>
<Function>PQresetPoll</Function>
Reset the communication port with the backend, in a non-blocking manner.
<synopsis>
int PQresetStart(PGconn *conn);
</synopsis>
<synopsis>
PostgresPollingStatusType PQresetPoll(PGconn *conn);
</synopsis>
These functions will close the connection to the backend and attempt to
reestablish a new connection to the same postmaster, using all the same
parameters previously used. This may be useful for error recovery if a
working connection is lost. They differ from PQreset (above) in that they
act in a non-blocking manner. These functions suffer from the same
restrictions as PQconnectStart and PQconnectPoll.
</Para>
<Para>
Call PQresetStart. If it returns 0, the reset has failed. If it returns 1,
poll the reset using PQresetPoll in exactly the same way as you would
create the connection using PQconnectPoll.
</Para>
</ListItem>
</ItemizedList>
</Para>
......@@ -338,19 +568,25 @@ const char *PQoptions(const PGconn *conn)
<Para>
<Function>PQstatus</Function>
Returns the status of the connection.
The status can be <literal>CONNECTION_OK</literal> or <literal>CONNECTION_BAD</literal>.
<synopsis>
ConnStatusType PQstatus(const PGconn *conn)
</synopsis>
</Para>
<Para>
A failed connection attempt is signaled by status <literal>CONNECTION_BAD</literal>.
Ordinarily, an OK status will remain so until <function>PQfinish</function>, but a
The status can be one of a number of values. However, only two of these are
seen outside of an asynchronous connection procedure -
<literal>CONNECTION_OK</literal> or <literal>CONNECTION_BAD</literal>. A good
connection to the database has the status CONNECTION_OK. A failed connection
attempt is signaled by status <literal>CONNECTION_BAD</literal>. Ordinarily,
an OK status will remain so until <function>PQfinish</function>, but a
communications failure might result in the status changing to
<literal>CONNECTION_BAD</literal> prematurely. In that case the application could
try to recover by calling <function>PQreset</function>.
<literal>CONNECTION_BAD</literal> prematurely. In that case the application
could try to recover by calling <function>PQreset</function>.
</Para>
<Para>
See the entry for PQconnectStart and PQconnectPoll with regards to other status codes
that might be seen.
</ListItem>
<ListItem>
......@@ -385,6 +621,60 @@ server host, not the local host!
</Para>
</ListItem>
<ListItem>
<Para>
<Function>PQsetenvStart</Function>
<Function>PQsetenvPoll</Function>
<Function>PQsetenvAbort</Function>
Perform an environment negotiation.
<synopsis>
PGsetenvHandle *PQsetenvStart(PGconn *conn)
</synopsis>
<synopsis>
PostgresPollingStatusType *PQsetenvPoll(PGsetenvHandle handle)
</synopsis>
<synopsis>
void PQsetenvAbort(PGsetenvHandle handle)
</synopsis>
These two routines can be used to re-perform the environment negotiation
that occurs during the opening of a connection to a database server. I have
no idea why this might be useful (XXX anyone?) but it might prove useful
for users to be able to reconfigure their character encodings on-the-fly,
for example.
</Para>
<Para>
These functions will not block, subject to the restrictions applied to
PQconnectStart and PQconnectPoll.
</Para>
<Para>
To begin, call handle=PQsetenvStart(conn), where conn is an open connection
to the database server. If handle is NULL, then libpq has been unable to
allocate a new PGsetenvHandle structure. Otherwise, a valid handle is
returned. This handle is intended to be opaque - you may only use it to
call other functions in libpq (PQsetenvPoll, for example).
</Para>
<Para>
Poll the procedure using PQsetenvPoll, in exactly the same way as you would
create a connection using PQconnectPoll.
</Para>
<Para>
The procedure may be aborted at any time by calling PQsetenvAbort(handle).
</Para>
<Para>
These functions are not thread-safe.
</Para>
</ListItem>
<ListItem>
<Para>
<Function>PQsetenv</Function>
Perform an environment negotiation.
<synopsis>
int PQsetenv(PGconn *conn)
</synopsis>
This function performs the same duties as PQsetenvStart and PQsetenvPoll, but
blocks to do so. It returns 1 on success and 0 on failure.
</Para>
</ItemizedList>
</Para>
</Sect1>
......
src/interfaces/libpq/fe-connect.c
View file @ 3ab5b1f1
......@@ -7,11 +7,13 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.106 1999/11/11 00:10:13 momjian Exp $
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.107 1999/11/30 03:08:18 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
......@@ -27,6 +29,7 @@
#include <unistd.h>
#include <netdb.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#endif
#ifndef HAVE_STRDUP
......@@ -40,11 +43,37 @@
#include "mb/pg_wchar.h"
#endif
/* ----------
* pg_setenv_state
* A struct used when polling a setenv request. This is referred to externally
* using a PGsetenvHandle.
* ----------
*/
struct pg_setenv_state
{
enum
{
SETENV_STATE_OPTION_SEND, /* About to send an Environment Option */
SETENV_STATE_OPTION_WAIT, /* Waiting for above send to complete */
#ifdef MULTIBYTE
SETENV_STATE_ENCODINGS_SEND, /* About to send an "encodings" query */
SETENV_STATE_ENCODINGS_WAIT, /* Waiting for query to complete */
#endif
SETENV_STATE_OK,
SETENV_STATE_FAILED
} state;
PGconn *conn;
PGresult *res;
struct EnvironmentOptions *eo;
} ;
static int connectDBStart(PGconn *conn);
static int connectDBComplete(PGconn *conn);
#ifdef USE_SSL
static SSL_CTX *SSL_context = NULL;
#endif
static ConnStatusType connectDB(PGconn *conn);
static PGconn *makeEmptyPGconn(void);
static void freePGconn(PGconn *conn);
static void closePGconn(PGconn *conn);
......@@ -53,9 +82,6 @@ static char *conninfo_getval(char *keyword);
static void conninfo_free(void);
static void defaultNoticeProcessor(void *arg, const char *message);
/* XXX Why is this not static? */
void PQsetenv(PGconn *conn);
#define NOTIFYLIST_INITIAL_SIZE 10
#define NOTIFYLIST_GROWBY 10
......@@ -98,6 +124,9 @@ static PQconninfoOption PQconninfoOptions[] = {
{"host", "PGHOST", NULL, NULL,
"Database-Host", "", 40},
{"hostaddr", "PGHOSTADDR", NULL, NULL,
"Database-Host-IPv4-Address", "", 15}, /* Room for abc.def.ghi.jkl */
{"port", "PGPORT", DEF_PGPORT, NULL,
"Database-Port", "", 6},
......@@ -145,27 +174,86 @@ static struct EnvironmentOptions
}
};
/* ----------------
* Connecting to a Database
*
* There are now four different ways a user of this API can connect to the
* database. Two are not recommended for use in new code, because of their
* lack of extensibility with respect to the passing of options to the
* backend. These are PQsetdb and PQsetdbLogin (the former now being a macro
* to the latter).
*
* If it is desired to connect in a synchronous (blocking) manner, use the
* function PQconnectdb.
*
* To connect in an asychronous (non-blocking) manner, use the functions
* PQconnectStart, and PQconnectPoll.
*
* Internally, the static functions connectDBStart, connectDBComplete
* are part of the connection procedure.
*
* ----------------
*/
/* ----------------
* PQconnectdb
*
* establishes a connection to a postgres backend through the postmaster
* using connection information in a string.
*
* The conninfo string is a list of
* The conninfo string is a white-separated list of
*
* option = value
*
* definitions. Value might be a single value containing no whitespaces
* or a single quoted string. If a single quote should appear everywhere
* in the value, it must be escaped with a backslash like \'
* definitions. Value might be a single value containing no whitespaces or
* a single quoted string. If a single quote should appear anywhere in
* the value, it must be escaped with a backslash like \'
*
* Returns a PGconn* which is needed for all subsequent libpq calls
* if the status field of the connection returned is CONNECTION_BAD,
* then some fields may be null'ed out instead of having valid values
* ----------------
*/
* Returns a PGconn* which is needed for all subsequent libpq calls, or NULL
* if a memory allocation failed.
* If the status field of the connection returned is CONNECTION_BAD,
* then some fields may be null'ed out instead of having valid values.
*
* You should call PQfinish (if conn is not NULL) regardless of whether this
* call succeeded.
*
* ---------------- */
PGconn *
PQconnectdb(const char *conninfo)
{
PGconn *conn = PQconnectStart(conninfo);
(void)(!conn || (conn->status == CONNECTION_BAD) ||
!connectDBComplete(conn));
return conn;
}
/* ----------------
* PQconnectStart
*
* Begins the establishment of a connection to a postgres backend through the
* postmaster using connection information in a string.
*
* See comment for PQconnectdb for the definition of the string format.
*
* Returns a PGconn*. If NULL is returned, a malloc error has occurred, and
* you should not attempt to proceed with this connection. If the status
* field of the connection returned is CONNECTION_BAD, an error has
* occurred. In this case you should call PQfinish on the result, (perhaps
* inspecting the error message first). Other fields of the structure may not
* be valid if that occurs. If the status field is not CONNECTION_BAD, then
* this stage has succeeded - call PQconnectPoll, using select(2) to see when
* this is necessary.
*
* See PQconnectPoll for more info.
*
* ---------------- */
PGconn *
PQconnectStart(const char *conninfo)
{
PGconn *conn;
char *tmp;
......@@ -174,6 +262,7 @@ PQconnectdb(const char *conninfo)
* Allocate memory for the conn structure
* ----------
*/
conn = makeEmptyPGconn();
if (conn == NULL)
return (PGconn *) NULL;
......@@ -188,6 +277,8 @@ PQconnectdb(const char *conninfo)
conninfo_free();
return conn;
}
tmp = conninfo_getval("hostaddr");
conn->pghostaddr = tmp ? strdup(tmp) : NULL;
tmp = conninfo_getval("host");
conn->pghost = tmp ? strdup(tmp) : NULL;
tmp = conninfo_getval("port");
......@@ -213,7 +304,11 @@ PQconnectdb(const char *conninfo)
* Connect to the database
* ----------
*/
conn->status = connectDB(conn);
if (!connectDBStart(conn))
{
/* Just in case we failed to set it in connectDBStart */
conn->status = CONNECTION_BAD;
}
return conn;
}
......@@ -384,10 +479,14 @@ PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions, cons
}
if (error)
{
conn->status = CONNECTION_BAD;
}
else
conn->status = connectDB(conn);
{
(void)(!connectDBStart(conn) || !connectDBComplete(conn));
}
return conn;
}
......@@ -480,7 +579,9 @@ update_db_info(PGconn *conn)
if (strcmp(old + offset, "localhost") != 0)
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- non-tcp access only possible on localhost\n");
"connectDBStart() -- "
"non-tcp access only possible on "
"localhost\n");
return 1;
}
}
......@@ -494,24 +595,84 @@ update_db_info(PGconn *conn)
return 0;
}
/*
* connectDB -
* make a connection to the backend so it is ready to receive queries.
* return CONNECTION_OK if successful, CONNECTION_BAD if not.
*
/* ----------
* connectMakeNonblocking -
* Make a connection non-blocking.
* Returns 1 if successful, 0 if not.
* ----------
*/
static ConnStatusType
connectDB(PGconn *conn)
static int
connectMakeNonblocking(PGconn *conn)
{
#ifndef WIN32
if (fcntl(conn->sock, F_SETFL, O_NONBLOCK) < 0)
#else
if (ioctlsocket(conn->sock, FIONBIO, &on) != 0)
#endif
{
printfPQExpBuffer(&conn->errorMessage,
"connectMakeNonblocking -- fcntl() failed: errno=%d\n%s\n",
errno, strerror(errno));
return 0;
}
return 1;
}
/* ----------
* connectNoDelay -
* Sets the TCP_NODELAY socket option.
* Returns 1 if successful, 0 if not.
* ----------
*/
static int
connectNoDelay(PGconn *conn)
{
struct protoent *pe;
int on = 1;
pe = getprotobyname("TCP");
if (pe == NULL)
{
printfPQExpBuffer(&conn->errorMessage,
"connectNoDelay() -- "
"getprotobyname failed: errno=%d\n%s\n",
errno, strerror(errno));
return 0;
}
if (setsockopt(conn->sock, pe->p_proto, TCP_NODELAY,
#ifdef WIN32
(char *)
#endif
&on,
sizeof(on)) < 0)
{
printfPQExpBuffer(&conn->errorMessage,
"connectNoDelay() -- setsockopt failed: errno=%d\n%s\n",
errno, strerror(errno));
#ifdef WIN32
printf("Winsock error: %i\n", WSAGetLastError());
#endif
return 0;
}
return 1;
}
/* ----------
* connectDBStart -
* Start to make a connection to the backend so it is ready to receive
* queries.
* Returns 1 if successful, 0 if not.
* ----------
*/
static int
connectDBStart(PGconn *conn)
{
PGresult *res;
struct hostent *hp;
StartupPacket sp;
AuthRequest areq;
SOCKET_SIZE_TYPE laddrlen;
int portno,
family;
char beresp;
int on = 1;
#ifdef USE_SSL
StartupPacket np; /* Used to negotiate SSL connection */
char SSLok;
......@@ -519,92 +680,126 @@ connectDB(PGconn *conn)
int tried_ssl = 0; /* Set if SSL negotiation was tried */
#endif
if (!conn)
return 0;
/*
* parse dbName to get all additional info in it, if any
*/
if (update_db_info(conn) != 0)
goto connect_errReturn;
/* Ensure our buffers are empty */
conn->inStart = conn->inCursor = conn->inEnd = 0;
conn->outCount = 0;
/*
* Initialize the startup packet.
* Set up the connection to postmaster/backend.
* Note that this supports IPv4 and UDP only.
*/
MemSet((char *) &sp, 0, sizeof(StartupPacket));
sp.protoVersion = (ProtocolVersion) htonl(PG_PROTOCOL_LIBPQ);
MemSet((char *) &conn->raddr, 0, sizeof(conn->raddr));
strncpy(sp.user, conn->pguser, SM_USER);
strncpy(sp.database, conn->dbName, SM_DATABASE);
strncpy(sp.tty, conn->pgtty, SM_TTY);
if (conn->pghostaddr != NULL)
{
/* Using pghostaddr avoids a hostname lookup */
/* Note that this supports IPv4 only */
struct in_addr addr;
if (conn->pgoptions)
strncpy(sp.options, conn->pgoptions, SM_OPTIONS);
if(!inet_aton(conn->pghostaddr, &addr))
{
printfPQExpBuffer(&conn->errorMessage,
"connectDBStart() -- "
"invalid host address: %s\n", conn->pghostaddr);
goto connect_errReturn;
}
/*
* Open a connection to postmaster/backend.
*/
family = AF_INET;
if (conn->pghost != NULL)
memmove((char *) &(conn->raddr.in.sin_addr),
(char *) &addr, sizeof(addr));
}
else if (conn->pghost != NULL)
{
/* Using pghost, so we have to look-up the hostname */
struct hostent *hp;
hp = gethostbyname(conn->pghost);
if ((hp == NULL) || (hp->h_addrtype != AF_INET))
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- unknown hostname: %s\n",
"connectDBStart() -- unknown hostname: %s\n",
conn->pghost);
goto connect_errReturn;
}
family = AF_INET;
memmove((char *) &(conn->raddr.in.sin_addr),
(char *) hp->h_addr,
hp->h_length);
}
else
{
hp = NULL;
/* pghostaddr and pghost are NULL, so use UDP */
family = AF_UNIX;
}
MemSet((char *) &conn->raddr, 0, sizeof(conn->raddr));
/* Set family */
conn->raddr.sa.sa_family = family;
/* Set port number */
portno = atoi(conn->pgport);
if (family == AF_INET)
{
memmove((char *) &(conn->raddr.in.sin_addr),
(char *) hp->h_addr,
hp->h_length);
conn->raddr.in.sin_port = htons((unsigned short) (portno));
conn->raddr_len = sizeof(struct sockaddr_in);
}
#if !defined(WIN32) && !defined(__CYGWIN32__)
else
conn->raddr_len = UNIXSOCK_PATH(conn->raddr.un, portno);
else
conn->raddr_len = UNIXSOCK_PATH(conn->raddr.un, portno);
#endif
/* Connect to the server */
/* Open a socket */
if ((conn->sock = socket(family, SOCK_STREAM, 0)) < 0)
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- socket() failed: errno=%d\n%s\n",
"connectDBStart() -- "
"socket() failed: errno=%d\n%s\n",
errno, strerror(errno));
goto connect_errReturn;
}
if (connect(conn->sock, &conn->raddr.sa, conn->raddr_len) < 0)
/* ----------
* Set the right options. Normally, we need nonblocking I/O, and we don't
* want delay of outgoing data for AF_INET sockets. If we are using SSL,
* then we need the blocking I/O (XXX Can this be fixed?).
* ---------- */
if (family == AF_INET)
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- connect() failed: %s\n"
"Is the postmaster running%s at '%s' and accepting connections on %s '%s'?\n",
strerror(errno),
(family == AF_INET) ? " (with -i)" : "",
conn->pghost ? conn->pghost : "localhost",
(family == AF_INET) ? "TCP/IP port" : "Unix socket",
conn->pgport);
goto connect_errReturn;
if (!connectNoDelay(conn))
goto connect_errReturn;
}
/* ----------
* Since I have no idea whether this is a valid thing to do under Windows
* before a connection is made, and since I have no way of testing it, I
* leave the code looking as below. When someone decides that they want
* non-blocking connections under Windows, they can define
* WIN32_NON_BLOCKING_CONNECTIONS before compilation. If it works, then
* this code can be cleaned up.
*
* Ewan Mellor <eem21@cam.ac.uk>.
* ---------- */
#if (!defined(WIN32) || defined(WIN32_NON_BLOCKING_CONNECTIONS)) && !defined(USE_SSL)
if (!connectMakeNonblocking(conn))
goto connect_errReturn;
#endif
#ifdef USE_SSL
/* This needs to be done before we set into nonblocking, since SSL negotiation
* does not like that mode */
#ifdef USE_SSL
/* Attempt to negotiate SSL usage */
if (allow_ssl_try) {
tried_ssl = 1;
......@@ -653,7 +848,7 @@ connectDB(PGconn *conn)
fprintf(conn->Pfdebug, "Backend reports error, attempting fallback to pre-6.6.\n");
close(conn->sock);
allow_ssl_try = 0;
return connectDB(conn);
return connectDBStart(conn);
}
else if (SSLok != 'N') {
strcpy(conn->errorMessage,
......@@ -665,242 +860,812 @@ connectDB(PGconn *conn)
allow_ssl_try = 1; /* We'll allow an attempt to use SSL next time */
#endif
/*
* Set the right options. We need nonblocking I/O, and we don't want
* delay of outgoing data.
/* ----------
* Start / make connection. We are hopefully in non-blocking mode
* now, but it is possible that:
* 1. Older systems will still block on connect, despite the
* non-blocking flag. (Anyone know if this is true?)
* 2. We are running under Windows, and aren't even trying
* to be non-blocking (see above).
* 3. We are using SSL.
* Thus, we have make arrangements for all eventualities.
* ----------
*/
#ifndef WIN32
if (fcntl(conn->sock, F_SETFL, O_NONBLOCK) < 0)
#else
if (ioctlsocket(conn->sock, FIONBIO, &on) != 0)
#endif
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- fcntl() failed: errno=%d\n%s\n",
errno, strerror(errno));
goto connect_errReturn;
}
if (family == AF_INET)
if (connect(conn->sock, &conn->raddr.sa, conn->raddr_len) < 0)
{
struct protoent *pe;
pe = getprotobyname("TCP");
if (pe == NULL)
if (errno == EINPROGRESS)
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB(): getprotobyname failed\n");
goto connect_errReturn;
/* This is fine - we're in non-blocking mode, and the
* connection is in progress. */
conn->status = CONNECTION_STARTED;
}
if (setsockopt(conn->sock, pe->p_proto, TCP_NODELAY,
#ifdef WIN32
(char *)
#endif
&on,
sizeof(on)) < 0)
else
{
/* Something's gone wrong */
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- setsockopt failed: errno=%d\n%s\n",
errno, strerror(errno));
#ifdef WIN32
printf("Winsock error: %i\n", WSAGetLastError());
#endif
"connectDBStart() -- connect() failed: %s\n"
"Is the postmaster running%s at '%s' "
"and accepting connections on %s '%s'?\n",
strerror(errno),
(family == AF_INET) ? " (with -i)" : "",
conn->pghost ? conn->pghost : "localhost",
(family == AF_INET) ?
"TCP/IP port" : "Unix socket",
conn->pgport);
goto connect_errReturn;
}
}
/* Fill in the client address */
laddrlen = sizeof(conn->laddr);
if (getsockname(conn->sock, &conn->laddr.sa, &laddrlen) < 0)
else
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- getsockname() failed: errno=%d\n%s\n",
errno, strerror(errno));
goto connect_errReturn;
/* We're connected already */
conn->status = CONNECTION_MADE;
}
/* Ensure our buffers are empty */
conn->inStart = conn->inCursor = conn->inEnd = 0;
conn->outCount = 0;
/* This makes the connection non-blocking, for all those cases which forced us
not to do it above. */
#if (defined(WIN32) && !defined(WIN32_NON_BLOCKING_CONNECTIONS)) || defined(USE_SSL)
if (!connectMakeNonblocking(conn))
goto connect_errReturn;
#endif
/* Send the startup packet. */
return 1;
if (pqPacketSend(conn, (char *) &sp, sizeof(StartupPacket)) != STATUS_OK)
connect_errReturn:
if (conn->sock >= 0)
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- couldn't send startup packet: errno=%d\n%s\n",
errno, strerror(errno));
goto connect_errReturn;
#ifdef WIN32
closesocket(conn->sock);
#else
close(conn->sock);
#endif
conn->sock = -1;
}
conn->status = CONNECTION_BAD;
/*
* Perform the authentication exchange: wait for backend messages and
* respond as necessary. We fall out of this loop when done talking to
* the postmaster.
*/
return 0;
}
for (;;)
{
/* Wait for some data to arrive (or for the channel to close) */
if (pqWait(TRUE, FALSE, conn))
goto connect_errReturn;
/* Load data, or detect EOF */
if (pqReadData(conn) < 0)
goto connect_errReturn;
/*
* Scan the message. If we run out of data, loop around to try
* again.
*/
conn->inCursor = conn->inStart;
/* ----------------
* connectDBComplete
*
* Block and complete a connection.
*
* Returns 1 on success, 0 on failure.
* ----------------
*/
static int
connectDBComplete(PGconn *conn)
{
PostgresPollingStatusType flag;
int r = 0, w = 1;
if (pqGetc(&beresp, conn))
continue; /* no data yet */
do
{
if(pqWait(r, w, conn))
{
conn->status = CONNECTION_BAD;
return 0;
}
/* Handle errors. */
if (beresp == 'E')
again:
switch(flag = PQconnectPoll(conn))
{
if (pqGets(&conn->errorMessage, conn))
continue;
goto connect_errReturn;
case PGRES_POLLING_ACTIVE:
goto again;
case PGRES_POLLING_OK:
break;
case PGRES_POLLING_READING:
r = 1;
w = 0;
break;
case PGRES_POLLING_WRITING:
r = 0;
w = 1;
break;
default:
/* Just in case we failed to set it in PQconnectPoll */
conn->status = CONNECTION_BAD;
return 0;
}
} while (flag != PGRES_POLLING_OK);
return 1;
}
/* ----------------
* PQconnectPoll
*
* Poll an asynchronous connection.
*
* Returns a PostgresPollingStatusType.
* Before calling this function, use select(2) to determine when data arrive.
*
* You must call PQfinish whether or not this fails.
*
* This function and PQconnectStart are intended to allow connections to be
* made without blocking the execution of your program on remote I/O. However,
* there are a number of caveats:
*
* o If you call PQtrace, ensure that the stream object into which you trace
will not block.
* o If you do not supply an IP address for the remote host (i.e. you
* supply a host name instead) then this function will block on
* gethostbyname. You will be fine if using UDP (i.e. by supplying
* neither a host name nor a host address).
* o If your backend wants to use Kerberos authentication then you must
* supply both a host name and a host address, otherwise this function
* may block on gethostname.
* o This function will block if compiled with USE_SSL.
*
* ---------------- */
PostgresPollingStatusType
PQconnectPoll(PGconn *conn)
{
PGresult *res;
/* Otherwise it should be an authentication request. */
if (beresp != 'R')
if (conn == NULL)
return PGRES_POLLING_FAILED;
/* Get the new data */
switch (conn->status)
{
/* We really shouldn't have been polled in these two cases, but
we can handle it. */
case CONNECTION_BAD:
return PGRES_POLLING_FAILED;
case CONNECTION_OK:
return PGRES_POLLING_OK;
/* These are reading states */
case CONNECTION_AWAITING_RESPONSE:
case CONNECTION_AUTH_RESPONSE:
case CONNECTION_ERROR_RESPONSE:
case CONNECTION_AUTH_OK:
{
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- expected authentication request\n");
goto connect_errReturn;
/* Load waiting data */
int n = pqReadData(conn);
if (n < 0)
goto error_return;
if (n == 0)
return PGRES_POLLING_READING;
break;
}
/* Get the type of request. */
if (pqGetInt((int *) &areq, 4, conn))
continue;
/* These are writing states, so we just proceed. */
case CONNECTION_STARTED:
case CONNECTION_MADE:
break;
/* Get the password salt if there is one. */
if (areq == AUTH_REQ_CRYPT)
case CONNECTION_SETENV:
/* We allow PQsetenvPoll to decide whether to proceed */
break;
default:
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- unknown connection state - "
"probably indicative of memory corruption!\n");
goto error_return;
}
keep_going: /* We will come back to here until there is nothing left to
parse. */
switch(conn->status)
{
case CONNECTION_STARTED:
{
if (pqGetnchar(conn->salt, sizeof(conn->salt), conn))
continue;
SOCKET_SIZE_TYPE laddrlen;
int optval;
socklen_t optlen = sizeof(int);
/* Write ready, since we've made it here, so the connection
* has been made. */
/* Now check (using getsockopt) that there is not an error
state waiting for us on the socket. */
if (getsockopt(conn->sock, SOL_SOCKET, SO_ERROR,
&optval, &optlen) == -1)
{
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- getsockopt() failed: "
"errno=%d\n%s\n",
errno, strerror(errno));
goto error_return;
}
else if (optval != 0)
{
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- "
"socket has error condition %d: %s.\n",
optval, strerror(optval));
goto error_return;
}
/* Fill in the client address */
laddrlen = sizeof(conn->laddr);
if (getsockname(conn->sock, &conn->laddr.sa, &laddrlen) < 0)
{
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- getsockname() failed: "
"errno=%d\n%s\n",
errno, strerror(errno));
goto error_return;
}
conn->status = CONNECTION_MADE;
return PGRES_POLLING_WRITING;
}
/* OK, we successfully read the message; mark data consumed */
conn->inStart = conn->inCursor;
case CONNECTION_MADE:
{
StartupPacket sp;
/*
* Initialize the startup packet.
*/
/* Respond to the request if necessary. */
/* fe-auth.c has not been fixed to support PQExpBuffers, so: */
if (fe_sendauth(areq, conn, conn->pghost, conn->pgpass,
conn->errorMessage.data) != STATUS_OK)
MemSet((char *) &sp, 0, sizeof(StartupPacket));
sp.protoVersion = (ProtocolVersion) htonl(PG_PROTOCOL_LIBPQ);
strncpy(sp.user, conn->pguser, SM_USER);
strncpy(sp.database, conn->dbName, SM_DATABASE);
strncpy(sp.tty, conn->pgtty, SM_TTY);
if (conn->pgoptions)
strncpy(sp.options, conn->pgoptions, SM_OPTIONS);
/* Send the startup packet. */
if (pqPacketSend(conn, (char *) &sp,
sizeof(StartupPacket)) != STATUS_OK)
{
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- "
"couldn't send startup packet: "
"errno=%d\n%s\n",
errno, strerror(errno));
goto error_return;
}
conn->status = CONNECTION_AWAITING_RESPONSE;
return PGRES_POLLING_READING;
}
/*
* Handle the authentication exchange: wait for backend messages
* and respond as necessary.
*/
case CONNECTION_AWAITING_RESPONSE:
{
char beresp;
/* Scan the message */
conn->inCursor = conn->inStart;
if (pqGetc(&beresp, conn))
{
/* We'll come back when there are more data */
return PGRES_POLLING_READING;
}
/* Handle errors. */
if (beresp == 'E')
{
conn->status = CONNECTION_ERROR_RESPONSE;
goto keep_going;
}
/* Otherwise it should be an authentication request. */
if (beresp != 'R')
{
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- expected authentication "
"request\n");
goto error_return;
}
/* Got an authentication request, so that's OK */
conn->status = CONNECTION_AUTH_RESPONSE;
goto keep_going;
}
case CONNECTION_AUTH_RESPONSE:
{
AuthRequest areq;
/* Get the type of request. */
if (pqGetInt((int *) &areq, 4, conn))
{
/* We'll come back when there are more data */
return PGRES_POLLING_READING;
}
/* Get the password salt if there is one. */
if (areq == AUTH_REQ_CRYPT)
{
if (pqGetnchar(conn->salt, sizeof(conn->salt), conn))
{
/* We'll come back when there are more data */
return PGRES_POLLING_READING;
}
}
/* OK, we successfully read the message; mark data consumed */
conn->inStart = conn->inCursor;
/* Respond to the request if necessary. */
/* Note that conn->pghost must be non-NULL if we are going
* avoid the Kerberos code doing a hostname look-up. */
/* XXX fe-auth.c has not been fixed to support PQExpBuffers, so: */
if (fe_sendauth(areq, conn, conn->pghost, conn->pgpass,
conn->errorMessage.data) != STATUS_OK)
{
conn->errorMessage.len = strlen(conn->errorMessage.data);
goto error_return;
}
conn->errorMessage.len = strlen(conn->errorMessage.data);
goto connect_errReturn;
/* This function has a section near the end that looks like it
* should block. I think that it will be OK though, since the
* socket is non-blocking, and thus the data should get out
* as quickly as possible. */
if (pqFlush(conn))
goto error_return;
if (areq == AUTH_REQ_OK)
{
/* We are done with authentication exchange */
conn->status = CONNECTION_AUTH_OK;
/* Set asyncStatus so that PQsetResult will think that what
* comes back next is the result of a query. See below. */
conn->asyncStatus = PGASYNC_BUSY;
goto keep_going;
}
conn->status = CONNECTION_AWAITING_RESPONSE;
return PGRES_POLLING_READING;
}
if (pqFlush(conn))
goto connect_errReturn;
case CONNECTION_ERROR_RESPONSE:
if (pqGets(&conn->errorMessage, conn))
{
/* We'll come back when there are more data */
return PGRES_POLLING_READING;
}
goto error_return;
/* Are we done? */
if (areq == AUTH_REQ_OK)
break;
}
case CONNECTION_AUTH_OK:
{
/* ----------
* Now we expect to hear from the backend. A ReadyForQuery
* message indicates that startup is successful, but we might
* also get an Error message indicating failure. (Notice
* messages indicating nonfatal warnings are also allowed by
* the protocol, as is a BackendKeyData message.) Easiest way
* to handle this is to let PQgetResult() read the messages. We
* just have to fake it out about the state of the connection.
*----------
*/
/*
* Now we expect to hear from the backend. A ReadyForQuery message
* indicates that startup is successful, but we might also get an
* Error message indicating failure. (Notice messages indicating
* nonfatal warnings are also allowed by the protocol, as is a
* BackendKeyData message.) Easiest way to handle this is to let
* PQgetResult() read the messages. We just have to fake it out about
* the state of the connection.
*/
if (!PQconsumeInput(conn))
goto error_return;
conn->status = CONNECTION_OK;
conn->asyncStatus = PGASYNC_BUSY;
res = PQgetResult(conn);
/* NULL return indicating we have gone to IDLE state is expected */
if (res)
{
if (res->resultStatus != PGRES_FATAL_ERROR)
if(PQisBusy(conn))
return PGRES_POLLING_READING;
res = PQgetResult(conn);
/* NULL return indicating we have gone to
IDLE state is expected */
if (res)
{
if (res->resultStatus != PGRES_FATAL_ERROR)
printfPQExpBuffer(&conn->errorMessage,
"PQconnectPoll() -- unexpected message "
"during startup\n");
PQclear(res);
goto error_return;
}
/*
* Post-connection housekeeping. Send environment variables
* to server.
*/
if ((conn->setenv_handle = PQsetenvStart(conn)) == NULL)
goto error_return;
conn->status = CONNECTION_SETENV;
goto keep_going;
}
case CONNECTION_SETENV:
/* We pretend that the connection is OK for the duration of
theses queries. */
conn->status = CONNECTION_OK;
switch(PQsetenvPoll(conn->setenv_handle))
{
case PGRES_POLLING_OK: /* Success */
conn->status = CONNECTION_OK;
return PGRES_POLLING_OK;
case PGRES_POLLING_READING: /* Still going */
conn->status = CONNECTION_SETENV;
return PGRES_POLLING_READING;
case PGRES_POLLING_WRITING: /* Still going */
conn->status = CONNECTION_SETENV;
return PGRES_POLLING_WRITING;
default:
conn->status = CONNECTION_SETENV;
goto error_return;
}
/* Unreachable */
default:
printfPQExpBuffer(&conn->errorMessage,
"connectDB() -- unexpected message during startup\n");
PQclear(res);
goto connect_errReturn;
"PQconnectPoll() -- unknown connection state - "
"probably indicative of memory corruption!\n",
sizeof(conn->errorMessage));
goto error_return;
}
/*
* Post-connection housekeeping. Send environment variables to server
/* Unreachable */
error_return:
/* ----------
* We used to close the socket at this point, but that makes it awkward
* for those above us if they wish to remove this socket from their
* own records (an fd_set for example). We'll just have this socket
* closed when PQfinish is called (which is compulsory even after an
* error, since the connection structure must be freed).
* ----------
*/
return PGRES_POLLING_FAILED;
}
PQsetenv(conn);
return CONNECTION_OK;
/* ----------------
* PQsetenvStart
*
* Starts the process of passing the values of a standard set of environment
* variables to the backend.
*
* ---------------- */
PGsetenvHandle
PQsetenvStart(PGconn *conn)
{
struct pg_setenv_state *handle;
connect_errReturn:
if (conn->sock >= 0)
if ((handle = malloc(sizeof(struct pg_setenv_state))) == NULL)
{
#ifdef WIN32
closesocket(conn->sock);
#else
close(conn->sock);
#endif
conn->sock = -1;
printfPQExpBuffer(&conn->errorMessage,
"PQsetenvStart() -- malloc error - %s\n",
strerror(errno));
return NULL;
}
return CONNECTION_BAD;
handle->conn = conn;
handle->res = NULL;
handle->eo = EnvironmentOptions;
#ifdef MULTIBYTE
handle->state = SETENV_STATE_ENCODINGS_SEND;
#else
handle->state = SETENV_STATE_OPTION_SEND;
#endif
return handle; /* Note that a struct pg_setenv_state * is the same as a
PGsetenvHandle */
}
void
PQsetenv(PGconn *conn)
/* ----------------
* PQsetenvPoll
*
* Polls the process of passing the values of a standard set of environment
* variables to the backend.
*
* ---------------- */
PostgresPollingStatusType
PQsetenvPoll(PGsetenvHandle handle)
{
struct EnvironmentOptions *eo;
char setQuery[100]; /* note length limits in sprintf's below */
const char *val;
PGresult *res;
#ifdef MULTIBYTE
char *envname = "PGCLIENTENCODING";
const char envname[] = "PGCLIENTENCODING";
#endif
/* Set env. variable PGCLIENTENCODING if it's not set already */
val = getenv(envname);
if (!val || *val == '\0')
if (!handle || handle->state == SETENV_STATE_FAILED)
return PGRES_POLLING_FAILED;
/* Check whether there are any data for us */
switch (handle->state)
{
const char *encoding = NULL;
/* query server encoding */
res = PQexec(conn, "select getdatabaseencoding()");
if (res && PQresultStatus(res) == PGRES_TUPLES_OK)
encoding = PQgetvalue(res, 0, 0);
if (!encoding) /* this should not happen */
encoding = pg_encoding_to_char(MULTIBYTE);
if (encoding)
/* These are reading states */
#ifdef MULTIBYTE
case SETENV_STATE_ENCODINGS_WAIT:
#endif
case SETENV_STATE_OPTION_WAIT:
{
/* set client encoding via environment variable */
char *envbuf;
/* Load waiting data */
int n = pqReadData(handle->conn);
if (n < 0)
goto error_return;
if (n == 0)
return PGRES_POLLING_READING;
envbuf = (char *) malloc(strlen(envname) + strlen(encoding) + 2);
sprintf(envbuf, "%s=%s", envname, encoding);
putenv(envbuf);
break;
}
PQclear(res);
}
/* These are writing states, so we just proceed. */
#ifdef MULTIBYTE
case SETENV_STATE_ENCODINGS_SEND:
#endif
case SETENV_STATE_OPTION_SEND:
break;
default:
printfPQExpBuffer(&handle->conn->errorMessage,
"PQsetenvPoll() -- unknown state - "
"probably indicative of memory corruption!\n");
goto error_return;
}
for (eo = EnvironmentOptions; eo->envName; eo++)
keep_going: /* We will come back to here until there is nothing left to
parse. */
switch(handle->state)
{
if ((val = getenv(eo->envName)))
#ifdef MULTIBYTE
case SETENV_STATE_ENCODINGS_SEND:
{
if (strcasecmp(val, "default") == 0)
sprintf(setQuery, "SET %s = %.60s", eo->pgName, val);
else
sprintf(setQuery, "SET %s = '%.60s'", eo->pgName, val);
const char *env;
/* query server encoding */
env = getenv(envname);
if (!env || *env == '\0')
{
if (!PQsendQuery(handle->conn,
"select getdatabaseencoding()"))
goto error_return;
handle->state = SETENV_STATE_ENCODINGS_WAIT;
return PGRES_POLLING_READING;
}
}
case SETENV_STATE_ENCODINGS_WAIT:
{
const char *encoding = 0;
if (!PQconsumeInput(handle->conn))
goto error_return;
if (PQisBusy(handle->conn))
return PGRES_POLLING_READING;
handle->res = PQgetResult(handle->conn);
if (handle->res)
{
if (PQresultStatus(handle->res) != PGRES_TUPLES_OK)
{
PQclear(handle->res);
goto error_return;
}
encoding = PQgetvalue(handle->res, 0, 0);
if (!encoding) /* this should not happen */
encoding = pg_encoding_to_char(MULTIBYTE);
if (encoding)
{
/* set client encoding via environment variable */
char *envbuf;
envbuf = (char *) malloc(strlen(envname) + strlen(encoding) + 2);
sprintf(envbuf, "%s=%s", envname, encoding);
putenv(envbuf);
}
PQclear(handle->res);
/* We have to keep going in order to clear up the query */
goto keep_going;
}
/* NULL result indicates that the query is finished */
/* Move on to setting the environment options */
handle->state = SETENV_STATE_OPTION_SEND;
goto keep_going;
}
#endif
case SETENV_STATE_OPTION_SEND:
{
/* Send an Environment Option */
char setQuery[100]; /* note length limits in sprintf's below */
if (handle->eo->envName)
{
const char *val;
if ((val = getenv(handle->eo->envName)))
{
if (strcasecmp(val, "default") == 0)
sprintf(setQuery, "SET %s = %.60s",
handle->eo->pgName, val);
else
sprintf(setQuery, "SET %s = '%.60s'",
handle->eo->pgName, val);
#ifdef CONNECTDEBUG
printf("Use environment variable %s to send %s\n", eo->envName, setQuery);
printf("Use environment variable %s to send %s\n",
handle->eo->envName, setQuery);
#endif
res = PQexec(conn, setQuery);
PQclear(res); /* Don't care? */
if (!PQsendQuery(handle->conn, setQuery))
goto error_return;
handle->state = SETENV_STATE_OPTION_WAIT;
}
else
{
handle->eo++;
}
}
else
{
/* No option to send, so we are done. */
handle->state = SETENV_STATE_OK;
}
goto keep_going;
}
case SETENV_STATE_OPTION_WAIT:
{
if (!PQconsumeInput(handle->conn))
goto error_return;
if (PQisBusy(handle->conn))
return PGRES_POLLING_READING;
handle->res = PQgetResult(handle->conn);
if (handle->res)
{
if (PQresultStatus(handle->res) != PGRES_COMMAND_OK)
{
PQclear(handle->res);
goto error_return;
}
/* Don't need the result */
PQclear(handle->res);
/* We have to keep going in order to clear up the query */
goto keep_going;
}
/* NULL result indicates that the query is finished */
/* Send the next option */
handle->eo++;
handle->state = SETENV_STATE_OPTION_SEND;
goto keep_going;
}
case SETENV_STATE_OK:
/* Tidy up */
free(handle);
return PGRES_POLLING_OK;
default:
printfPQExpBuffer(&handle->conn->errorMessage,
"PQsetenvPoll() -- unknown state - "
"probably indicative of memory corruption!\n");
goto error_return;
}
/* Unreachable */
error_return:
handle->state = SETENV_STATE_FAILED; /* This may protect us even if we
* are called after the handle
* has been freed. */
free(handle);
return PGRES_POLLING_FAILED;
}
/* ----------------
* PQsetenvAbort
*
* Aborts the process of passing the values of a standard set of environment
* variables to the backend.
*
* ---------------- */
void
PQsetenvAbort(PGsetenvHandle handle)
{
/* We should not have been called in the FAILED state, but we can cope by
* not freeing the handle (it has probably been freed by now anyway). */
if (handle->state != SETENV_STATE_FAILED)
{
handle->state = SETENV_STATE_FAILED;
free(handle);
}
} /* PQsetenv() */
}
/* ----------------
* PQsetenv
*
* Passes the values of a standard set of environment variables to the
* backend.
*
* Returns 1 on success, 0 on failure.
*
* This function used to return void. I don't think that there should be
* compatibility problems caused by giving it a return value, especially as
* this function has not been documented previously.
*
* ---------------- */
int
PQsetenv(PGconn *conn)
{
PostgresPollingStatusType flag;
PGsetenvHandle handle;
int r = 0, w = 1;
if((handle = PQsetenvStart(conn)) == NULL)
return 0;
do
{
if(pqWait(r, w, conn))
{
/* XXX This is not a good sign - perhaps we should mark the
connection as bad here... */
return 0;
}
again:
switch(flag = PQsetenvPoll(handle))
{
case PGRES_POLLING_ACTIVE:
goto again;
case PGRES_POLLING_OK:
break;
case PGRES_POLLING_READING:
r = 1;
w = 0;
break;
case PGRES_POLLING_WRITING:
r = 0;
w = 1;
break;
default: /* Failed */
return 0;
}
} while (flag != PGRES_POLLING_OK);
return 1;
}
/*
* makeEmptyPGconn
......@@ -973,6 +1738,8 @@ freePGconn(PGconn *conn)
#endif
if (conn->pghost)
free(conn->pghost);
if (conn->pghostaddr)
free(conn->pghostaddr);
if (conn->pgport)
free(conn->pgport);
if (conn->pgtty)
......@@ -1006,6 +1773,12 @@ freePGconn(PGconn *conn)
static void
closePGconn(PGconn *conn)
{
if (conn->status == CONNECTION_SETENV)
{
/* We have to abort the setenv process as well */
PQsetenvAbort(conn->setenv_handle);
}
if (conn->sock >= 0)
{
......@@ -1067,8 +1840,47 @@ PQreset(PGconn *conn)
if (conn)
{
closePGconn(conn);
conn->status = connectDB(conn);
(void)(!connectDBStart(conn) || !connectDBComplete(conn));
}
return;
}
/* PQresetStart :
resets the connection to the backend
closes the existing connection and makes a new one
Returns 1 on success, 0 on failure.
*/
int
PQresetStart(PGconn *conn)
{
if (conn)
{
closePGconn(conn);
return connectDBStart(conn);
}
return 1;
}
/* PQresetPoll :
resets the connection to the backend
closes the existing connection and makes a new one
*/
PostgresPollingStatusType
PQresetPoll(PGconn *conn)
{
if (conn)
{
return PQconnectPoll(conn);
}
return PGRES_POLLING_FAILED;
}
......
src/interfaces/libpq/fe-misc.c
View file @ 3ab5b1f1
......@@ -24,7 +24,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.32 1999/11/11 00:10:14 momjian Exp $
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.33 1999/11/30 03:08:19 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -269,29 +269,69 @@ pqPutInt(int value, size_t bytes, PGconn *conn)
/* --------------------------------------------------------------------- */
/* pqReadReady: is select() saying the file is ready to read?
* Returns -1 on failure, 0 if not ready, 1 if ready.
*/
static int
int
pqReadReady(PGconn *conn)
{
fd_set input_mask;
struct timeval timeout;
if (conn->sock < 0)
return 0;
if (!conn || conn->sock < 0)
return -1;
FD_ZERO(&input_mask);
FD_SET(conn->sock, &input_mask);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
retry:
if (select(conn->sock + 1, &input_mask, (fd_set *) NULL, (fd_set *) NULL,
&timeout) < 0)
{
if (errno == EINTR)
/* Interrupted system call - we'll just try again */
goto retry;
printfPQExpBuffer(&conn->errorMessage,
"pqReadReady() -- select() failed: errno=%d\n%s\n",
errno, strerror(errno));
return 0;
return -1;
}
return FD_ISSET(conn->sock, &input_mask) ? 1 : 0;
}
/* --------------------------------------------------------------------- */
/* pqWriteReady: is select() saying the file is ready to write?
* Returns -1 on failure, 0 if not ready, 1 if ready.
*/
int
pqWriteReady(PGconn *conn)
{
fd_set input_mask;
struct timeval timeout;
if (!conn || conn->sock < 0)
return -1;
FD_ZERO(&input_mask);
FD_SET(conn->sock, &input_mask);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
retry:
if (select(conn->sock + 1, (fd_set *) NULL, &input_mask, (fd_set *) NULL,
&timeout) < 0)
{
if (errno == EINTR)
/* Interrupted system call - we'll just try again */
goto retry;
printfPQExpBuffer(&conn->errorMessage,
"pqWriteReady() -- select() failed: errno=%d\n%s\n",
errno, strerror(errno));
return -1;
}
return FD_ISSET(conn->sock, &input_mask);
return FD_ISSET(conn->sock, &input_mask) ? 1 : 0;
}
/* --------------------------------------------------------------------- */
......@@ -418,8 +458,17 @@ tryAgain:
* be taken much, since in normal practice we should not be trying to
* read data unless the file selected for reading already.
*/
if (!pqReadReady(conn))
return 0; /* definitely no data available */
switch (pqReadReady(conn))
{
case 0:
/* definitely no data available */
return 0;
case 1:
/* ready for read */
break;
default:
goto definitelyFailed;
}
/*
* Still not sure that it's EOF, because some data could have just
......@@ -570,6 +619,10 @@ pqFlush(PGconn *conn)
if (len > 0)
{
/* We didn't send it all, wait till we can send more */
/* At first glance this looks as though it should block. I think
* that it will be OK though, as long as the socket is
* non-blocking. */
if (pqWait(FALSE, TRUE, conn))
return EOF;
}
......@@ -599,9 +652,9 @@ pqWait(int forRead, int forWrite, PGconn *conn)
return EOF;
}
/* loop in case select returns EINTR */
for (;;)
if (forRead || forWrite)
{
retry:
FD_ZERO(&input_mask);
FD_ZERO(&output_mask);
if (forRead)
......@@ -612,14 +665,12 @@ pqWait(int forRead, int forWrite, PGconn *conn)
(struct timeval *) NULL) < 0)
{
if (errno == EINTR)
continue;
goto retry;
printfPQExpBuffer(&conn->errorMessage,
"pqWait() -- select() failed: errno=%d\n%s\n",
errno, strerror(errno));
return EOF;
}
/* On nonerror return, assume we're done */
break;
}
return 0;
......
src/interfaces/libpq/libpq-fe.h
View file @ 3ab5b1f1
......@@ -6,7 +6,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: libpq-fe.h,v 1.52 1999/11/11 00:10:14 momjian Exp $
* $Id: libpq-fe.h,v 1.53 1999/11/30 03:08:19 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -29,10 +29,40 @@ extern "C"
typedef enum
{
/* Although you may decide to change this list in some way,
values which become unused should never be removed, nor
should constants be redefined - that would break
compatibility with existing code. */
CONNECTION_OK,
CONNECTION_BAD
CONNECTION_BAD,
/* Non-blocking mode only below here */
/* The existence of these should never be relied upon - they
should only be used for user feedback or similar purposes. */
CONNECTION_STARTED, /* Waiting for connection to be made. */
CONNECTION_MADE, /* Connection OK; waiting to send. */
CONNECTION_AWAITING_RESPONSE, /* Waiting for a response
from the backend. */
CONNECTION_AUTH_RESPONSE, /* Got an authentication
response; about to deal
with it. */
CONNECTION_ERROR_RESPONSE, /* Got an error
response; about to deal
with it. */
CONNECTION_AUTH_OK, /* Received authentication;
waiting for ReadyForQuery
etc. */
CONNECTION_SETENV /* Negotiating environment. */
} ConnStatusType;
typedef enum
{
PGRES_POLLING_FAILED = 0,
PGRES_POLLING_READING, /* These two indicate that one may */
PGRES_POLLING_WRITING, /* use select before polling again. */
PGRES_POLLING_OK,
PGRES_POLLING_ACTIVE /* Can call poll function immediately.*/
} PostgresPollingStatusType;
typedef enum
{
PGRES_EMPTY_QUERY = 0,
......@@ -67,6 +97,12 @@ extern "C"
*/
typedef struct pg_result PGresult;
/* PGsetenvHandle is an opaque handle which is returned by PQsetenvStart and
* which should be passed to PQsetenvPoll or PQsetenvAbort in order to refer
* to the particular process being performed.
*/
typedef struct pg_setenv_state *PGsetenvHandle;
/* PGnotify represents the occurrence of a NOTIFY message.
* Ideally this would be an opaque typedef, but it's so simple that it's
* unlikely to change.
......@@ -152,11 +188,15 @@ extern "C"
/* === in fe-connect.c === */
/* make a new client connection to the backend */
/* Asynchronous (non-blocking) */
extern PGconn *PQconnectStart(const char *conninfo);
extern PostgresPollingStatusType PQconnectPoll(PGconn *conn);
/* Synchronous (blocking) */
extern PGconn *PQconnectdb(const char *conninfo);
extern PGconn *PQsetdbLogin(const char *pghost, const char *pgport,
const char *pgoptions, const char *pgtty,
const char *dbName,
const char *login, const char *pwd);
const char *dbName,
const char *login, const char *pwd);
#define PQsetdb(M_PGHOST,M_PGPORT,M_PGOPT,M_PGTTY,M_DBNAME) \
PQsetdbLogin(M_PGHOST, M_PGPORT, M_PGOPT, M_PGTTY, M_DBNAME, NULL, NULL)
......@@ -170,6 +210,10 @@ extern "C"
* close the current connection and restablish a new one with the same
* parameters
*/
/* Asynchronous (non-blocking) */
extern int PQresetStart(PGconn *conn);
extern PostgresPollingStatusType PQresetPoll(PGconn *conn);
/* Synchronous (blocking) */
extern void PQreset(PGconn *conn);
/* issue a cancel request */
......@@ -195,6 +239,15 @@ extern "C"
/* Override default notice processor */
extern PQnoticeProcessor PQsetNoticeProcessor(PGconn *conn, PQnoticeProcessor proc, void *arg);
/* Passing of environment variables */
/* Asynchronous (non-blocking) */
extern PGsetenvHandle PQsetenvStart(PGconn *conn);
extern PostgresPollingStatusType PQsetenvPoll(PGsetenvHandle handle);
extern void PQsetenvAbort(PGsetenvHandle handle);
/* Synchronous (blocking) */
extern int PQsetenv(PGconn *conn);
/* === in fe-exec.c === */
/* Simple synchronous query */
......
src/interfaces/libpq/libpq-int.h
View file @ 3ab5b1f1
......@@ -11,7 +11,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: libpq-int.h,v 1.13 1999/11/11 00:10:14 momjian Exp $
* $Id: libpq-int.h,v 1.14 1999/11/30 03:08:19 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -168,6 +168,10 @@ struct pg_conn
/* Saved values of connection options */
char *pghost; /* the machine on which the server is
* running */
char *pghostaddr; /* the IPv4 address of the machine on
* which the server is running, in
* IPv4 numbers-and-dots notation. Takes
* precedence over above. */
char *pgport; /* the server's communication port */
char *pgtty; /* tty on which the backend messages is
* displayed (NOT ACTUALLY USED???) */
......@@ -220,6 +224,9 @@ struct pg_conn
PGresult *result; /* result being constructed */
PGresAttValue *curTuple; /* tuple currently being read */
/* Handle for setenv request. Used during connection only. */
PGsetenvHandle setenv_handle;
#ifdef USE_SSL
SSL *ssl;
#endif
......@@ -268,6 +275,8 @@ extern int pqPutInt(int value, size_t bytes, PGconn *conn);
extern int pqReadData(PGconn *conn);
extern int pqFlush(PGconn *conn);
extern int pqWait(int forRead, int forWrite, PGconn *conn);
extern int pqReadReady(PGconn *conn);
extern int pqWriteReady(PGconn *conn);
/* bits in a byte */
#define BYTELEN 8
......
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