1 /*-------------------------------------------------------------------------
4 * This file contains internal definitions meant to be used only by
5 * the frontend libpq library, not by applications that call it.
7 * An application can include this file if it wants to bypass the
8 * official API defined by libpq-fe.h, but code that does so is much
9 * more likely to break across PostgreSQL releases than code that uses
10 * only the official API.
12 * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
13 * Portions Copyright (c) 1994, Regents of the University of California
15 * $PostgreSQL: pgsql/src/interfaces/libpq/libpq-int.h,v 1.153 2010/07/14 17:09:45 tgl Exp $
17 *-------------------------------------------------------------------------
23 /* We assume libpq-fe.h has already been included. */
24 #include "postgres_fe.h"
25 #include "libpq-events.h"
28 #include <sys/types.h>
33 #ifdef ENABLE_THREAD_SAFETY
35 #include "pthread-win32.h"
42 /* include stuff common to fe and be */
43 #include "getaddrinfo.h"
44 #include "libpq/pqcomm.h"
45 /* include stuff found in fe only */
46 #include "pqexpbuffer.h"
49 #if defined(HAVE_GSSAPI_H)
52 #include <gssapi/gssapi.h>
57 #define SECURITY_WIN32
58 #if defined(WIN32) && !defined(WIN32_ONLY_COMPILER)
66 * Define a fake structure compatible with GSSAPI on Unix.
74 #endif /* ENABLE_SSPI */
77 #include <openssl/ssl.h>
78 #include <openssl/err.h>
80 #if (SSLEAY_VERSION_NUMBER >= 0x00907000L) && !defined(OPENSSL_NO_ENGINE)
81 #define USE_SSL_ENGINE
86 * POSTGRES backend dependent Constants.
88 #define CMDSTATUS_LEN 64 /* should match COMPLETION_TAG_BUFSIZE */
91 * PGresult and the subsidiary types PGresAttDesc, PGresAttValue
92 * represent the result of a query (or more precisely, of a single SQL
93 * command --- a query string given to PQexec can contain multiple commands).
94 * Note we assume that a single command can return at most one tuple group,
95 * hence there is no need for multiple descriptor sets.
98 /* Subsidiary-storage management structure for PGresult.
99 * See space management routines in fe-exec.c for details.
100 * Note that space[k] refers to the k'th byte starting from the physical
101 * head of the block --- it's a union, not a struct!
103 typedef union pgresult_data PGresult_data;
107 PGresult_data *next; /* link to next block, or NULL */
108 char space[1]; /* dummy for accessing block as bytes */
111 /* Data about a single parameter of a prepared statement */
112 typedef struct pgresParamDesc
114 Oid typid; /* type id */
118 * Data for a single attribute of a single tuple
120 * We use char* for Attribute values.
122 * The value pointer always points to a null-terminated area; we add a
123 * null (zero) byte after whatever the backend sends us. This is only
124 * particularly useful for text values ... with a binary value, the
125 * value might have embedded nulls, so the application can't use C string
126 * operators on it. But we add a null anyway for consistency.
127 * Note that the value itself does not contain a length word.
129 * A NULL attribute is a special case in two ways: its len field is NULL_LEN
130 * and its value field points to null_field in the owning PGresult. All the
131 * NULL attributes in a query result point to the same place (there's no need
132 * to store a null string separately for each one).
135 #define NULL_LEN (-1) /* pg_result len for NULL value */
137 typedef struct pgresAttValue
139 int len; /* length in bytes of the value */
140 char *value; /* actual value, plus terminating zero byte */
143 /* Typedef for message-field list entries */
144 typedef struct pgMessageField
146 struct pgMessageField *next; /* list link */
147 char code; /* field code */
148 char contents[1]; /* field value (VARIABLE LENGTH) */
151 /* Fields needed for notice handling */
154 PQnoticeReceiver noticeRec; /* notice message receiver */
156 PQnoticeProcessor noticeProc; /* notice message processor */
160 typedef struct PGEvent
162 PGEventProc proc; /* the function to call on events */
163 char *name; /* used only for error messages */
164 void *passThrough; /* pointer supplied at registration time */
165 void *data; /* optional state (instance) data */
166 bool resultInitialized; /* T if RESULTCREATE/COPY succeeded */
173 PGresAttDesc *attDescs;
174 PGresAttValue **tuples; /* each PGresTuple is an array of
176 int tupArrSize; /* allocated size of tuples array */
178 PGresParamDesc *paramDescs;
179 ExecStatusType resultStatus;
180 char cmdStatus[CMDSTATUS_LEN]; /* cmd status from the query */
181 int binary; /* binary tuple values if binary == 1,
185 * These fields are copied from the originating PGconn, so that operations
186 * on the PGresult don't have to reference the PGconn.
188 PGNoticeHooks noticeHooks;
191 int client_encoding; /* encoding id */
194 * Error information (all NULL if not an error result). errMsg is the
195 * "overall" error message returned by PQresultErrorMessage. If we have
196 * per-field info then it is stored in a linked list.
198 char *errMsg; /* error message, or NULL if no error */
199 PGMessageField *errFields; /* message broken into fields */
201 /* All NULL attributes in the query result point to this null string */
205 * Space management information. Note that attDescs and error stuff, if
206 * not null, point into allocated blocks. But tuples points to a
207 * separately malloc'd block, so that we can realloc it.
209 PGresult_data *curBlock; /* most recently allocated block */
210 int curOffset; /* start offset of free space in block */
211 int spaceLeft; /* number of free bytes remaining in block */
214 /* PGAsyncStatusType defines the state of the query-execution state machine */
217 PGASYNC_IDLE, /* nothing's happening, dude */
218 PGASYNC_BUSY, /* query in progress */
219 PGASYNC_READY, /* result ready for PQgetResult */
220 PGASYNC_COPY_IN, /* Copy In data transfer in progress */
221 PGASYNC_COPY_OUT /* Copy Out data transfer in progress */
224 /* PGQueryClass tracks which query protocol we are now executing */
227 PGQUERY_SIMPLE, /* simple Query protocol (PQexec) */
228 PGQUERY_EXTENDED, /* full Extended protocol (PQexecParams) */
229 PGQUERY_PREPARE, /* Parse only (PQprepare) */
230 PGQUERY_DESCRIBE /* Describe Statement or Portal */
233 /* PGSetenvStatusType defines the state of the PQSetenv state machine */
234 /* (this is used only for 2.0-protocol connections) */
237 SETENV_STATE_OPTION_SEND, /* About to send an Environment Option */
238 SETENV_STATE_OPTION_WAIT, /* Waiting for above send to complete */
239 SETENV_STATE_QUERY1_SEND, /* About to send a status query */
240 SETENV_STATE_QUERY1_WAIT, /* Waiting for query to complete */
241 SETENV_STATE_QUERY2_SEND, /* About to send a status query */
242 SETENV_STATE_QUERY2_WAIT, /* Waiting for query to complete */
244 } PGSetenvStatusType;
246 /* Typedef for the EnvironmentOptions[] array */
247 typedef struct PQEnvironmentOption
249 const char *envName, /* name of an environment variable */
250 *pgName; /* name of corresponding SET variable */
251 } PQEnvironmentOption;
253 /* Typedef for parameter-status list entries */
254 typedef struct pgParameterStatus
256 struct pgParameterStatus *next; /* list link */
257 char *name; /* parameter name */
258 char *value; /* parameter value */
259 /* Note: name and value are stored in same malloc block as struct is */
262 /* large-object-access data ... allocated only if large-object code is used. */
263 typedef struct pgLobjfuncs
265 Oid fn_lo_open; /* OID of backend function lo_open */
266 Oid fn_lo_close; /* OID of backend function lo_close */
267 Oid fn_lo_creat; /* OID of backend function lo_creat */
268 Oid fn_lo_create; /* OID of backend function lo_create */
269 Oid fn_lo_unlink; /* OID of backend function lo_unlink */
270 Oid fn_lo_lseek; /* OID of backend function lo_lseek */
271 Oid fn_lo_tell; /* OID of backend function lo_tell */
272 Oid fn_lo_truncate; /* OID of backend function lo_truncate */
273 Oid fn_lo_read; /* OID of backend function LOread */
274 Oid fn_lo_write; /* OID of backend function LOwrite */
278 * PGconn stores all the state data associated with a single connection
283 /* Saved values of connection options */
284 char *pghost; /* the machine on which the server is running */
285 char *pghostaddr; /* the numeric IP address of the machine on
286 * which the server is running. Takes
287 * precedence over above. */
288 char *pgport; /* the server's communication port */
289 char *pgunixsocket; /* the Unix-domain socket that the server is
290 * listening on; if NULL, uses a default
291 * constructed from pgport */
292 char *pgtty; /* tty on which the backend messages is
293 * displayed (OBSOLETE, NOT USED) */
294 char *connect_timeout; /* connection timeout (numeric string) */
295 char *pgoptions; /* options to start the backend with */
296 char *appname; /* application name */
297 char *fbappname; /* fallback application name */
298 char *dbName; /* database name */
299 char *replication; /* connect as the replication standby? */
300 char *pguser; /* Postgres username and password, if any */
302 char *keepalives; /* use TCP keepalives? */
303 char *keepalives_idle; /* time between TCP keepalives */
304 char *keepalives_interval; /* time between TCP keepalive
306 char *keepalives_count; /* maximum number of TCP keepalive
308 char *sslmode; /* SSL mode (require,prefer,allow,disable) */
309 char *sslkey; /* client key filename */
310 char *sslcert; /* client certificate filename */
311 char *sslrootcert; /* root certificate filename */
312 char *sslcrl; /* certificate revocation list filename */
314 #if defined(KRB5) || defined(ENABLE_GSS) || defined(ENABLE_SSPI)
315 char *krbsrvname; /* Kerberos service name */
318 /* Optional file to write trace info to */
321 /* Callback procedures for notice message processing */
322 PGNoticeHooks noticeHooks;
324 /* Event procs registered via PQregisterEventProc */
325 PGEvent *events; /* expandable array of event data */
326 int nEvents; /* number of active events */
327 int eventArraySize; /* allocated array size */
329 /* Status indicators */
330 ConnStatusType status;
331 PGAsyncStatusType asyncStatus;
332 PGTransactionStatusType xactStatus; /* never changes to ACTIVE */
333 PGQueryClass queryclass;
334 char *last_query; /* last SQL command, or NULL if unknown */
335 bool options_valid; /* true if OK to attempt connection */
336 bool nonblocking; /* whether this connection is using nonblock
337 * sending semantics */
338 char copy_is_binary; /* 1 = copy binary, 0 = copy text */
339 int copy_already_done; /* # bytes already returned in COPY
341 PGnotify *notifyHead; /* oldest unreported Notify msg */
342 PGnotify *notifyTail; /* newest unreported Notify msg */
344 /* Connection data */
345 int sock; /* Unix FD for socket, -1 if not connected */
346 SockAddr laddr; /* Local address */
347 SockAddr raddr; /* Remote address */
348 ProtocolVersion pversion; /* FE/BE protocol version in use */
349 int sversion; /* server version, e.g. 70401 for 7.4.1 */
350 bool password_needed; /* true if server demanded a password */
351 bool dot_pgpass_used; /* true if used .pgpass */
352 bool sigpipe_so; /* have we masked SIGPIPE via SO_NOSIGPIPE? */
353 bool sigpipe_flag; /* can we mask SIGPIPE via MSG_NOSIGNAL? */
355 /* Transient state needed while establishing connection */
356 struct addrinfo *addrlist; /* list of possible backend addresses */
357 struct addrinfo *addr_cur; /* the one currently being tried */
358 int addrlist_family; /* needed to know how to free addrlist */
359 PGSetenvStatusType setenv_state; /* for 2.0 protocol only */
360 const PQEnvironmentOption *next_eo;
361 bool send_appname; /* okay to send application_name? */
363 /* Miscellaneous stuff */
364 int be_pid; /* PID of backend --- needed for cancels */
365 int be_key; /* key of backend --- needed for cancels */
366 char md5Salt[4]; /* password salt received from backend */
367 pgParameterStatus *pstatus; /* ParameterStatus data */
368 int client_encoding; /* encoding id */
369 bool std_strings; /* standard_conforming_strings */
370 PGVerbosity verbosity; /* error/notice message verbosity */
371 PGlobjfuncs *lobjfuncs; /* private state for large-object access fns */
373 /* Buffer for data received from backend and not yet processed */
374 char *inBuffer; /* currently allocated buffer */
375 int inBufSize; /* allocated size of buffer */
376 int inStart; /* offset to first unconsumed data in buffer */
377 int inCursor; /* next byte to tentatively consume */
378 int inEnd; /* offset to first position after avail data */
380 /* Buffer for data not yet sent to backend */
381 char *outBuffer; /* currently allocated buffer */
382 int outBufSize; /* allocated size of buffer */
383 int outCount; /* number of chars waiting in buffer */
385 /* State for constructing messages in outBuffer */
386 int outMsgStart; /* offset to msg start (length word); if -1,
387 * msg has no length word */
388 int outMsgEnd; /* offset to msg end (so far) */
390 /* Status for asynchronous result construction */
391 PGresult *result; /* result being constructed */
392 PGresAttValue *curTuple; /* tuple currently being read */
395 bool allow_ssl_try; /* Allowed to try SSL negotiation */
396 bool wait_ssl_try; /* Delay SSL negotiation until after
397 * attempting normal connection */
398 SSL *ssl; /* SSL status, if have SSL connection */
399 X509 *peer; /* X509 cert of server */
400 char peer_dn[256 + 1]; /* peer distinguished name */
401 char peer_cn[SM_USER + 1]; /* peer common name */
402 #ifdef USE_SSL_ENGINE
403 ENGINE *engine; /* SSL engine, if any */
405 void *engine; /* dummy field to keep struct the same if
406 * OpenSSL version changes */
411 gss_ctx_id_t gctx; /* GSS context */
412 gss_name_t gtarg_nam; /* GSS target name */
413 gss_buffer_desc ginbuf; /* GSS input token */
414 gss_buffer_desc goutbuf; /* GSS output token */
419 gss_buffer_desc ginbuf; /* GSS input token */
421 char *gsslib; /* What GSS librart to use ("gssapi" or
424 CredHandle *sspicred; /* SSPI credentials handle */
425 CtxtHandle *sspictx; /* SSPI context */
426 char *sspitarget; /* SSPI target name */
427 int usesspi; /* Indicate if SSPI is in use on the
432 /* Buffer for current error message */
433 PQExpBufferData errorMessage; /* expansible string */
435 /* Buffer for receiving various parts of messages */
436 PQExpBufferData workBuffer; /* expansible string */
439 /* PGcancel stores all data necessary to cancel a connection. A copy of this
440 * data is required to safely cancel a connection running on a different
445 SockAddr raddr; /* Remote address */
446 int be_pid; /* PID of backend --- needed for cancels */
447 int be_key; /* key of backend --- needed for cancels */
451 /* String descriptions of the ExecStatusTypes.
452 * direct use of this array is deprecated; call PQresStatus() instead.
454 extern char *const pgresStatus[];
457 * Internal functions of libpq
458 * Functions declared here need to be visible across files of libpq,
459 * but are not intended to be called by applications. We use the
460 * convention "pqXXX" for internal functions, vs. the "PQxxx" names
461 * used for application-visible routines.
465 /* === in fe-connect.c === */
467 extern int pqPacketSend(PGconn *conn, char pack_type,
468 const void *buf, size_t buf_len);
469 extern bool pqGetHomeDirectory(char *buf, int bufsize);
471 #ifdef ENABLE_THREAD_SAFETY
472 extern pgthreadlock_t pg_g_threadlock;
474 #define PGTHREAD_ERROR(msg) \
476 fprintf(stderr, "%s\n", msg); \
481 #define pglock_thread() pg_g_threadlock(true)
482 #define pgunlock_thread() pg_g_threadlock(false)
484 #define pglock_thread() ((void) 0)
485 #define pgunlock_thread() ((void) 0)
488 /* === in fe-exec.c === */
490 extern void pqSetResultError(PGresult *res, const char *msg);
491 extern void pqCatenateResultError(PGresult *res, const char *msg);
492 extern void *pqResultAlloc(PGresult *res, size_t nBytes, bool isBinary);
493 extern char *pqResultStrdup(PGresult *res, const char *str);
494 extern void pqClearAsyncResult(PGconn *conn);
495 extern void pqSaveErrorResult(PGconn *conn);
496 extern PGresult *pqPrepareAsyncResult(PGconn *conn);
498 pqInternalNotice(const PGNoticeHooks *hooks, const char *fmt,...)
499 /* This lets gcc check the format string for consistency. */
500 __attribute__((format(printf, 2, 3)));
501 extern int pqAddTuple(PGresult *res, PGresAttValue *tup);
502 extern void pqSaveMessageField(PGresult *res, char code,
504 extern void pqSaveParameterStatus(PGconn *conn, const char *name,
506 extern void pqHandleSendFailure(PGconn *conn);
508 /* === in fe-protocol2.c === */
510 extern PostgresPollingStatusType pqSetenvPoll(PGconn *conn);
512 extern char *pqBuildStartupPacket2(PGconn *conn, int *packetlen,
513 const PQEnvironmentOption *options);
514 extern void pqParseInput2(PGconn *conn);
515 extern int pqGetCopyData2(PGconn *conn, char **buffer, int async);
516 extern int pqGetline2(PGconn *conn, char *s, int maxlen);
517 extern int pqGetlineAsync2(PGconn *conn, char *buffer, int bufsize);
518 extern int pqEndcopy2(PGconn *conn);
519 extern PGresult *pqFunctionCall2(PGconn *conn, Oid fnid,
520 int *result_buf, int *actual_result_len,
522 const PQArgBlock *args, int nargs);
524 /* === in fe-protocol3.c === */
526 extern char *pqBuildStartupPacket3(PGconn *conn, int *packetlen,
527 const PQEnvironmentOption *options);
528 extern void pqParseInput3(PGconn *conn);
529 extern int pqGetErrorNotice3(PGconn *conn, bool isError);
530 extern int pqGetCopyData3(PGconn *conn, char **buffer, int async);
531 extern int pqGetline3(PGconn *conn, char *s, int maxlen);
532 extern int pqGetlineAsync3(PGconn *conn, char *buffer, int bufsize);
533 extern int pqEndcopy3(PGconn *conn);
534 extern PGresult *pqFunctionCall3(PGconn *conn, Oid fnid,
535 int *result_buf, int *actual_result_len,
537 const PQArgBlock *args, int nargs);
539 /* === in fe-misc.c === */
542 * "Get" and "Put" routines return 0 if successful, EOF if not. Note that for
543 * Get, EOF merely means the buffer is exhausted, not that there is
544 * necessarily any error.
546 extern int pqCheckOutBufferSpace(size_t bytes_needed, PGconn *conn);
547 extern int pqCheckInBufferSpace(size_t bytes_needed, PGconn *conn);
548 extern int pqGetc(char *result, PGconn *conn);
549 extern int pqPutc(char c, PGconn *conn);
550 extern int pqGets(PQExpBuffer buf, PGconn *conn);
551 extern int pqGets_append(PQExpBuffer buf, PGconn *conn);
552 extern int pqPuts(const char *s, PGconn *conn);
553 extern int pqGetnchar(char *s, size_t len, PGconn *conn);
554 extern int pqPutnchar(const char *s, size_t len, PGconn *conn);
555 extern int pqGetInt(int *result, size_t bytes, PGconn *conn);
556 extern int pqPutInt(int value, size_t bytes, PGconn *conn);
557 extern int pqPutMsgStart(char msg_type, bool force_len, PGconn *conn);
558 extern int pqPutMsgEnd(PGconn *conn);
559 extern int pqReadData(PGconn *conn);
560 extern int pqFlush(PGconn *conn);
561 extern int pqWait(int forRead, int forWrite, PGconn *conn);
562 extern int pqWaitTimed(int forRead, int forWrite, PGconn *conn,
564 extern int pqReadReady(PGconn *conn);
565 extern int pqWriteReady(PGconn *conn);
567 /* === in fe-secure.c === */
569 extern int pqsecure_initialize(PGconn *);
570 extern void pqsecure_destroy(void);
571 extern PostgresPollingStatusType pqsecure_open_client(PGconn *);
572 extern void pqsecure_close(PGconn *);
573 extern ssize_t pqsecure_read(PGconn *, void *ptr, size_t len);
574 extern ssize_t pqsecure_write(PGconn *, const void *ptr, size_t len);
576 #if defined(ENABLE_THREAD_SAFETY) && !defined(WIN32)
577 extern int pq_block_sigpipe(sigset_t *osigset, bool *sigpipe_pending);
578 extern void pq_reset_sigpipe(sigset_t *osigset, bool sigpipe_pending,
583 * this is so that we can check if a connection is non-blocking internally
584 * without the overhead of a function call
586 #define pqIsnonblocking(conn) ((conn)->nonblocking)
590 libpq_gettext(const char *msgid)
591 __attribute__((format_arg(1)));
593 #define libpq_gettext(x) (x)
597 * These macros are needed to let error-handling code be portable between
598 * Unix and Windows. (ugh)
601 #define SOCK_ERRNO (WSAGetLastError())
602 #define SOCK_STRERROR winsock_strerror
603 #define SOCK_ERRNO_SET(e) WSASetLastError(e)
605 #define SOCK_ERRNO errno
606 #define SOCK_STRERROR pqStrerror
607 #define SOCK_ERRNO_SET(e) (errno = (e))
610 #endif /* LIBPQ_INT_H */