4564 lines
112 KiB
C
4564 lines
112 KiB
C
/*-------------------------------------------------------------------------
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*
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* fe-exec.c
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* functions related to sending a query down to the backend
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*
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* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* src/interfaces/libpq/fe-exec.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres_fe.h"
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#include <ctype.h>
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#include <fcntl.h>
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#include <limits.h>
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#ifdef WIN32
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#include "win32.h"
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#else
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#include <unistd.h>
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#endif
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#include "libpq-fe.h"
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#include "libpq-int.h"
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#include "mb/pg_wchar.h"
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/* keep this in same order as ExecStatusType in libpq-fe.h */
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char *const pgresStatus[] = {
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"PGRES_EMPTY_QUERY",
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"PGRES_COMMAND_OK",
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"PGRES_TUPLES_OK",
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"PGRES_COPY_OUT",
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"PGRES_COPY_IN",
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"PGRES_BAD_RESPONSE",
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"PGRES_NONFATAL_ERROR",
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"PGRES_FATAL_ERROR",
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"PGRES_COPY_BOTH",
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"PGRES_SINGLE_TUPLE",
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"PGRES_PIPELINE_SYNC",
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"PGRES_PIPELINE_ABORTED"
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};
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/* We return this if we're unable to make a PGresult at all */
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static const PGresult OOM_result = {
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.resultStatus = PGRES_FATAL_ERROR,
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.client_encoding = PG_SQL_ASCII,
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.errMsg = "out of memory\n",
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};
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/*
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* static state needed by PQescapeString and PQescapeBytea; initialize to
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* values that result in backward-compatible behavior
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*/
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static int static_client_encoding = PG_SQL_ASCII;
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static bool static_std_strings = false;
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static PGEvent *dupEvents(PGEvent *events, int count, size_t *memSize);
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static bool pqAddTuple(PGresult *res, PGresAttValue *tup,
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const char **errmsgp);
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static int PQsendQueryInternal(PGconn *conn, const char *query, bool newQuery);
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static bool PQsendQueryStart(PGconn *conn, bool newQuery);
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static int PQsendQueryGuts(PGconn *conn,
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const char *command,
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const char *stmtName,
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int nParams,
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const Oid *paramTypes,
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const char *const *paramValues,
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const int *paramLengths,
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const int *paramFormats,
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int resultFormat);
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static void parseInput(PGconn *conn);
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static PGresult *getCopyResult(PGconn *conn, ExecStatusType copytype);
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static bool PQexecStart(PGconn *conn);
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static PGresult *PQexecFinish(PGconn *conn);
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static int PQsendTypedCommand(PGconn *conn, char command, char type,
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const char *target);
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static int check_field_number(const PGresult *res, int field_num);
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static void pqPipelineProcessQueue(PGconn *conn);
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static int pqPipelineSyncInternal(PGconn *conn, bool immediate_flush);
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static int pqPipelineFlush(PGconn *conn);
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/* ----------------
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* Space management for PGresult.
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*
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* Formerly, libpq did a separate malloc() for each field of each tuple
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* returned by a query. This was remarkably expensive --- malloc/free
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* consumed a sizable part of the application's runtime. And there is
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* no real need to keep track of the fields separately, since they will
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* all be freed together when the PGresult is released. So now, we grab
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* large blocks of storage from malloc and allocate space for query data
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* within these blocks, using a trivially simple allocator. This reduces
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* the number of malloc/free calls dramatically, and it also avoids
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* fragmentation of the malloc storage arena.
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* The PGresult structure itself is still malloc'd separately. We could
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* combine it with the first allocation block, but that would waste space
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* for the common case that no extra storage is actually needed (that is,
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* the SQL command did not return tuples).
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*
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* We also malloc the top-level array of tuple pointers separately, because
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* we need to be able to enlarge it via realloc, and our trivial space
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* allocator doesn't handle that effectively. (Too bad the FE/BE protocol
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* doesn't tell us up front how many tuples will be returned.)
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* All other subsidiary storage for a PGresult is kept in PGresult_data blocks
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* of size PGRESULT_DATA_BLOCKSIZE. The overhead at the start of each block
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* is just a link to the next one, if any. Free-space management info is
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* kept in the owning PGresult.
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* A query returning a small amount of data will thus require three malloc
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* calls: one for the PGresult, one for the tuples pointer array, and one
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* PGresult_data block.
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*
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* Only the most recently allocated PGresult_data block is a candidate to
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* have more stuff added to it --- any extra space left over in older blocks
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* is wasted. We could be smarter and search the whole chain, but the point
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* here is to be simple and fast. Typical applications do not keep a PGresult
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* around very long anyway, so some wasted space within one is not a problem.
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*
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* Tuning constants for the space allocator are:
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* PGRESULT_DATA_BLOCKSIZE: size of a standard allocation block, in bytes
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* PGRESULT_ALIGN_BOUNDARY: assumed alignment requirement for binary data
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* PGRESULT_SEP_ALLOC_THRESHOLD: objects bigger than this are given separate
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* blocks, instead of being crammed into a regular allocation block.
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* Requirements for correct function are:
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* PGRESULT_ALIGN_BOUNDARY must be a multiple of the alignment requirements
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* of all machine data types. (Currently this is set from configure
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* tests, so it should be OK automatically.)
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* PGRESULT_SEP_ALLOC_THRESHOLD + PGRESULT_BLOCK_OVERHEAD <=
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* PGRESULT_DATA_BLOCKSIZE
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* pqResultAlloc assumes an object smaller than the threshold will fit
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* in a new block.
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* The amount of space wasted at the end of a block could be as much as
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* PGRESULT_SEP_ALLOC_THRESHOLD, so it doesn't pay to make that too large.
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* ----------------
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*/
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#define PGRESULT_DATA_BLOCKSIZE 2048
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#define PGRESULT_ALIGN_BOUNDARY MAXIMUM_ALIGNOF /* from configure */
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#define PGRESULT_BLOCK_OVERHEAD Max(sizeof(PGresult_data), PGRESULT_ALIGN_BOUNDARY)
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#define PGRESULT_SEP_ALLOC_THRESHOLD (PGRESULT_DATA_BLOCKSIZE / 2)
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/*
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* PQmakeEmptyPGresult
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* returns a newly allocated, initialized PGresult with given status.
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* If conn is not NULL and status indicates an error, the conn's
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* errorMessage is copied. Also, any PGEvents are copied from the conn.
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*
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* Note: the logic to copy the conn's errorMessage is now vestigial;
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* no internal caller uses it. However, that behavior is documented for
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* outside callers, so we'd better keep it.
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*/
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PGresult *
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PQmakeEmptyPGresult(PGconn *conn, ExecStatusType status)
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{
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PGresult *result;
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result = (PGresult *) malloc(sizeof(PGresult));
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if (!result)
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return NULL;
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result->ntups = 0;
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result->numAttributes = 0;
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result->attDescs = NULL;
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result->tuples = NULL;
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result->tupArrSize = 0;
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result->numParameters = 0;
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result->paramDescs = NULL;
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result->resultStatus = status;
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result->cmdStatus[0] = '\0';
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result->binary = 0;
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result->events = NULL;
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result->nEvents = 0;
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result->errMsg = NULL;
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result->errFields = NULL;
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result->errQuery = NULL;
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result->null_field[0] = '\0';
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result->curBlock = NULL;
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result->curOffset = 0;
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result->spaceLeft = 0;
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result->memorySize = sizeof(PGresult);
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if (conn)
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{
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/* copy connection data we might need for operations on PGresult */
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result->noticeHooks = conn->noticeHooks;
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result->client_encoding = conn->client_encoding;
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/* consider copying conn's errorMessage */
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switch (status)
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{
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case PGRES_EMPTY_QUERY:
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case PGRES_COMMAND_OK:
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case PGRES_TUPLES_OK:
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case PGRES_COPY_OUT:
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case PGRES_COPY_IN:
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case PGRES_COPY_BOTH:
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case PGRES_SINGLE_TUPLE:
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/* non-error cases */
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break;
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default:
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/* we intentionally do not use or modify errorReported here */
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pqSetResultError(result, &conn->errorMessage, 0);
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break;
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}
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/* copy events last; result must be valid if we need to PQclear */
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if (conn->nEvents > 0)
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{
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result->events = dupEvents(conn->events, conn->nEvents,
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&result->memorySize);
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if (!result->events)
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{
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PQclear(result);
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return NULL;
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}
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result->nEvents = conn->nEvents;
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}
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}
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else
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{
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/* defaults... */
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result->noticeHooks.noticeRec = NULL;
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result->noticeHooks.noticeRecArg = NULL;
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result->noticeHooks.noticeProc = NULL;
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result->noticeHooks.noticeProcArg = NULL;
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result->client_encoding = PG_SQL_ASCII;
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}
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return result;
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}
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/*
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* PQsetResultAttrs
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*
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* Set the attributes for a given result. This function fails if there are
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* already attributes contained in the provided result. The call is
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* ignored if numAttributes is zero or attDescs is NULL. If the
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* function fails, it returns zero. If the function succeeds, it
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* returns a non-zero value.
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*/
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int
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PQsetResultAttrs(PGresult *res, int numAttributes, PGresAttDesc *attDescs)
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{
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int i;
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/* Fail if argument is NULL or OOM_result */
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if (!res || (const PGresult *) res == &OOM_result)
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return false;
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/* If attrs already exist, they cannot be overwritten. */
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if (res->numAttributes > 0)
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return false;
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/* ignore no-op request */
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if (numAttributes <= 0 || !attDescs)
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return true;
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res->attDescs = (PGresAttDesc *)
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PQresultAlloc(res, numAttributes * sizeof(PGresAttDesc));
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if (!res->attDescs)
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return false;
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res->numAttributes = numAttributes;
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memcpy(res->attDescs, attDescs, numAttributes * sizeof(PGresAttDesc));
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/* deep-copy the attribute names, and determine format */
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res->binary = 1;
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for (i = 0; i < res->numAttributes; i++)
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{
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if (res->attDescs[i].name)
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res->attDescs[i].name = pqResultStrdup(res, res->attDescs[i].name);
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else
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res->attDescs[i].name = res->null_field;
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if (!res->attDescs[i].name)
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return false;
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if (res->attDescs[i].format == 0)
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res->binary = 0;
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}
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return true;
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}
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/*
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* PQcopyResult
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*
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* Returns a deep copy of the provided 'src' PGresult, which cannot be NULL.
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* The 'flags' argument controls which portions of the result will or will
|
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* NOT be copied. The created result is always put into the
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* PGRES_TUPLES_OK status. The source result error message is not copied,
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* although cmdStatus is.
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*
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* To set custom attributes, use PQsetResultAttrs. That function requires
|
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* that there are no attrs contained in the result, so to use that
|
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* function you cannot use the PG_COPYRES_ATTRS or PG_COPYRES_TUPLES
|
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* options with this function.
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*
|
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* Options:
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* PG_COPYRES_ATTRS - Copy the source result's attributes
|
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*
|
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* PG_COPYRES_TUPLES - Copy the source result's tuples. This implies
|
|
* copying the attrs, seeing how the attrs are needed by the tuples.
|
|
*
|
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* PG_COPYRES_EVENTS - Copy the source result's events.
|
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*
|
|
* PG_COPYRES_NOTICEHOOKS - Copy the source result's notice hooks.
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*/
|
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PGresult *
|
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PQcopyResult(const PGresult *src, int flags)
|
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{
|
|
PGresult *dest;
|
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int i;
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|
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if (!src)
|
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return NULL;
|
|
|
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dest = PQmakeEmptyPGresult(NULL, PGRES_TUPLES_OK);
|
|
if (!dest)
|
|
return NULL;
|
|
|
|
/* Always copy these over. Is cmdStatus really useful here? */
|
|
dest->client_encoding = src->client_encoding;
|
|
strcpy(dest->cmdStatus, src->cmdStatus);
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|
|
|
/* Wants attrs? */
|
|
if (flags & (PG_COPYRES_ATTRS | PG_COPYRES_TUPLES))
|
|
{
|
|
if (!PQsetResultAttrs(dest, src->numAttributes, src->attDescs))
|
|
{
|
|
PQclear(dest);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/* Wants to copy tuples? */
|
|
if (flags & PG_COPYRES_TUPLES)
|
|
{
|
|
int tup,
|
|
field;
|
|
|
|
for (tup = 0; tup < src->ntups; tup++)
|
|
{
|
|
for (field = 0; field < src->numAttributes; field++)
|
|
{
|
|
if (!PQsetvalue(dest, tup, field,
|
|
src->tuples[tup][field].value,
|
|
src->tuples[tup][field].len))
|
|
{
|
|
PQclear(dest);
|
|
return NULL;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Wants to copy notice hooks? */
|
|
if (flags & PG_COPYRES_NOTICEHOOKS)
|
|
dest->noticeHooks = src->noticeHooks;
|
|
|
|
/* Wants to copy PGEvents? */
|
|
if ((flags & PG_COPYRES_EVENTS) && src->nEvents > 0)
|
|
{
|
|
dest->events = dupEvents(src->events, src->nEvents,
|
|
&dest->memorySize);
|
|
if (!dest->events)
|
|
{
|
|
PQclear(dest);
|
|
return NULL;
|
|
}
|
|
dest->nEvents = src->nEvents;
|
|
}
|
|
|
|
/* Okay, trigger PGEVT_RESULTCOPY event */
|
|
for (i = 0; i < dest->nEvents; i++)
|
|
{
|
|
/* We don't fire events that had some previous failure */
|
|
if (src->events[i].resultInitialized)
|
|
{
|
|
PGEventResultCopy evt;
|
|
|
|
evt.src = src;
|
|
evt.dest = dest;
|
|
if (dest->events[i].proc(PGEVT_RESULTCOPY, &evt,
|
|
dest->events[i].passThrough))
|
|
dest->events[i].resultInitialized = true;
|
|
}
|
|
}
|
|
|
|
return dest;
|
|
}
|
|
|
|
/*
|
|
* Copy an array of PGEvents (with no extra space for more).
|
|
* Does not duplicate the event instance data, sets this to NULL.
|
|
* Also, the resultInitialized flags are all cleared.
|
|
* The total space allocated is added to *memSize.
|
|
*/
|
|
static PGEvent *
|
|
dupEvents(PGEvent *events, int count, size_t *memSize)
|
|
{
|
|
PGEvent *newEvents;
|
|
size_t msize;
|
|
int i;
|
|
|
|
if (!events || count <= 0)
|
|
return NULL;
|
|
|
|
msize = count * sizeof(PGEvent);
|
|
newEvents = (PGEvent *) malloc(msize);
|
|
if (!newEvents)
|
|
return NULL;
|
|
|
|
for (i = 0; i < count; i++)
|
|
{
|
|
newEvents[i].proc = events[i].proc;
|
|
newEvents[i].passThrough = events[i].passThrough;
|
|
newEvents[i].data = NULL;
|
|
newEvents[i].resultInitialized = false;
|
|
newEvents[i].name = strdup(events[i].name);
|
|
if (!newEvents[i].name)
|
|
{
|
|
while (--i >= 0)
|
|
free(newEvents[i].name);
|
|
free(newEvents);
|
|
return NULL;
|
|
}
|
|
msize += strlen(events[i].name) + 1;
|
|
}
|
|
|
|
*memSize += msize;
|
|
return newEvents;
|
|
}
|
|
|
|
|
|
/*
|
|
* Sets the value for a tuple field. The tup_num must be less than or
|
|
* equal to PQntuples(res). If it is equal, a new tuple is created and
|
|
* added to the result.
|
|
* Returns a non-zero value for success and zero for failure.
|
|
* (On failure, we report the specific problem via pqInternalNotice.)
|
|
*/
|
|
int
|
|
PQsetvalue(PGresult *res, int tup_num, int field_num, char *value, int len)
|
|
{
|
|
PGresAttValue *attval;
|
|
const char *errmsg = NULL;
|
|
|
|
/* Fail if argument is NULL or OOM_result */
|
|
if (!res || (const PGresult *) res == &OOM_result)
|
|
return false;
|
|
|
|
/* Invalid field_num? */
|
|
if (!check_field_number(res, field_num))
|
|
return false;
|
|
|
|
/* Invalid tup_num, must be <= ntups */
|
|
if (tup_num < 0 || tup_num > res->ntups)
|
|
{
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"row number %d is out of range 0..%d",
|
|
tup_num, res->ntups);
|
|
return false;
|
|
}
|
|
|
|
/* need to allocate a new tuple? */
|
|
if (tup_num == res->ntups)
|
|
{
|
|
PGresAttValue *tup;
|
|
int i;
|
|
|
|
tup = (PGresAttValue *)
|
|
pqResultAlloc(res, res->numAttributes * sizeof(PGresAttValue),
|
|
true);
|
|
|
|
if (!tup)
|
|
goto fail;
|
|
|
|
/* initialize each column to NULL */
|
|
for (i = 0; i < res->numAttributes; i++)
|
|
{
|
|
tup[i].len = NULL_LEN;
|
|
tup[i].value = res->null_field;
|
|
}
|
|
|
|
/* add it to the array */
|
|
if (!pqAddTuple(res, tup, &errmsg))
|
|
goto fail;
|
|
}
|
|
|
|
attval = &res->tuples[tup_num][field_num];
|
|
|
|
/* treat either NULL_LEN or NULL value pointer as a NULL field */
|
|
if (len == NULL_LEN || value == NULL)
|
|
{
|
|
attval->len = NULL_LEN;
|
|
attval->value = res->null_field;
|
|
}
|
|
else if (len <= 0)
|
|
{
|
|
attval->len = 0;
|
|
attval->value = res->null_field;
|
|
}
|
|
else
|
|
{
|
|
attval->value = (char *) pqResultAlloc(res, len + 1, true);
|
|
if (!attval->value)
|
|
goto fail;
|
|
attval->len = len;
|
|
memcpy(attval->value, value, len);
|
|
attval->value[len] = '\0';
|
|
}
|
|
|
|
return true;
|
|
|
|
/*
|
|
* Report failure via pqInternalNotice. If preceding code didn't provide
|
|
* an error message, assume "out of memory" was meant.
|
|
*/
|
|
fail:
|
|
if (!errmsg)
|
|
errmsg = libpq_gettext("out of memory");
|
|
pqInternalNotice(&res->noticeHooks, "%s", errmsg);
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* pqResultAlloc - exported routine to allocate local storage in a PGresult.
|
|
*
|
|
* We force all such allocations to be maxaligned, since we don't know
|
|
* whether the value might be binary.
|
|
*/
|
|
void *
|
|
PQresultAlloc(PGresult *res, size_t nBytes)
|
|
{
|
|
/* Fail if argument is NULL or OOM_result */
|
|
if (!res || (const PGresult *) res == &OOM_result)
|
|
return NULL;
|
|
|
|
return pqResultAlloc(res, nBytes, true);
|
|
}
|
|
|
|
/*
|
|
* pqResultAlloc -
|
|
* Allocate subsidiary storage for a PGresult.
|
|
*
|
|
* nBytes is the amount of space needed for the object.
|
|
* If isBinary is true, we assume that we need to align the object on
|
|
* a machine allocation boundary.
|
|
* If isBinary is false, we assume the object is a char string and can
|
|
* be allocated on any byte boundary.
|
|
*/
|
|
void *
|
|
pqResultAlloc(PGresult *res, size_t nBytes, bool isBinary)
|
|
{
|
|
char *space;
|
|
PGresult_data *block;
|
|
|
|
if (!res)
|
|
return NULL;
|
|
|
|
if (nBytes <= 0)
|
|
return res->null_field;
|
|
|
|
/*
|
|
* If alignment is needed, round up the current position to an alignment
|
|
* boundary.
|
|
*/
|
|
if (isBinary)
|
|
{
|
|
int offset = res->curOffset % PGRESULT_ALIGN_BOUNDARY;
|
|
|
|
if (offset)
|
|
{
|
|
res->curOffset += PGRESULT_ALIGN_BOUNDARY - offset;
|
|
res->spaceLeft -= PGRESULT_ALIGN_BOUNDARY - offset;
|
|
}
|
|
}
|
|
|
|
/* If there's enough space in the current block, no problem. */
|
|
if (nBytes <= (size_t) res->spaceLeft)
|
|
{
|
|
space = res->curBlock->space + res->curOffset;
|
|
res->curOffset += nBytes;
|
|
res->spaceLeft -= nBytes;
|
|
return space;
|
|
}
|
|
|
|
/*
|
|
* If the requested object is very large, give it its own block; this
|
|
* avoids wasting what might be most of the current block to start a new
|
|
* block. (We'd have to special-case requests bigger than the block size
|
|
* anyway.) The object is always given binary alignment in this case.
|
|
*/
|
|
if (nBytes >= PGRESULT_SEP_ALLOC_THRESHOLD)
|
|
{
|
|
size_t alloc_size = nBytes + PGRESULT_BLOCK_OVERHEAD;
|
|
|
|
block = (PGresult_data *) malloc(alloc_size);
|
|
if (!block)
|
|
return NULL;
|
|
res->memorySize += alloc_size;
|
|
space = block->space + PGRESULT_BLOCK_OVERHEAD;
|
|
if (res->curBlock)
|
|
{
|
|
/*
|
|
* Tuck special block below the active block, so that we don't
|
|
* have to waste the free space in the active block.
|
|
*/
|
|
block->next = res->curBlock->next;
|
|
res->curBlock->next = block;
|
|
}
|
|
else
|
|
{
|
|
/* Must set up the new block as the first active block. */
|
|
block->next = NULL;
|
|
res->curBlock = block;
|
|
res->spaceLeft = 0; /* be sure it's marked full */
|
|
}
|
|
return space;
|
|
}
|
|
|
|
/* Otherwise, start a new block. */
|
|
block = (PGresult_data *) malloc(PGRESULT_DATA_BLOCKSIZE);
|
|
if (!block)
|
|
return NULL;
|
|
res->memorySize += PGRESULT_DATA_BLOCKSIZE;
|
|
block->next = res->curBlock;
|
|
res->curBlock = block;
|
|
if (isBinary)
|
|
{
|
|
/* object needs full alignment */
|
|
res->curOffset = PGRESULT_BLOCK_OVERHEAD;
|
|
res->spaceLeft = PGRESULT_DATA_BLOCKSIZE - PGRESULT_BLOCK_OVERHEAD;
|
|
}
|
|
else
|
|
{
|
|
/* we can cram it right after the overhead pointer */
|
|
res->curOffset = sizeof(PGresult_data);
|
|
res->spaceLeft = PGRESULT_DATA_BLOCKSIZE - sizeof(PGresult_data);
|
|
}
|
|
|
|
space = block->space + res->curOffset;
|
|
res->curOffset += nBytes;
|
|
res->spaceLeft -= nBytes;
|
|
return space;
|
|
}
|
|
|
|
/*
|
|
* PQresultMemorySize -
|
|
* Returns total space allocated for the PGresult.
|
|
*/
|
|
size_t
|
|
PQresultMemorySize(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return 0;
|
|
return res->memorySize;
|
|
}
|
|
|
|
/*
|
|
* pqResultStrdup -
|
|
* Like strdup, but the space is subsidiary PGresult space.
|
|
*/
|
|
char *
|
|
pqResultStrdup(PGresult *res, const char *str)
|
|
{
|
|
char *space = (char *) pqResultAlloc(res, strlen(str) + 1, false);
|
|
|
|
if (space)
|
|
strcpy(space, str);
|
|
return space;
|
|
}
|
|
|
|
/*
|
|
* pqSetResultError -
|
|
* assign a new error message to a PGresult
|
|
*
|
|
* Copy text from errorMessage buffer beginning at given offset
|
|
* (it's caller's responsibility that offset is valid)
|
|
*/
|
|
void
|
|
pqSetResultError(PGresult *res, PQExpBuffer errorMessage, int offset)
|
|
{
|
|
char *msg;
|
|
|
|
if (!res)
|
|
return;
|
|
|
|
/*
|
|
* We handle two OOM scenarios here. The errorMessage buffer might be
|
|
* marked "broken" due to having previously failed to allocate enough
|
|
* memory for the message, or it might be fine but pqResultStrdup fails
|
|
* and returns NULL. In either case, just make res->errMsg point directly
|
|
* at a constant "out of memory" string.
|
|
*/
|
|
if (!PQExpBufferBroken(errorMessage))
|
|
msg = pqResultStrdup(res, errorMessage->data + offset);
|
|
else
|
|
msg = NULL;
|
|
if (msg)
|
|
res->errMsg = msg;
|
|
else
|
|
res->errMsg = libpq_gettext("out of memory\n");
|
|
}
|
|
|
|
/*
|
|
* PQclear -
|
|
* free's the memory associated with a PGresult
|
|
*/
|
|
void
|
|
PQclear(PGresult *res)
|
|
{
|
|
PGresult_data *block;
|
|
int i;
|
|
|
|
/* As a convenience, do nothing for a NULL pointer */
|
|
if (!res)
|
|
return;
|
|
/* Also, do nothing if the argument is OOM_result */
|
|
if ((const PGresult *) res == &OOM_result)
|
|
return;
|
|
|
|
/* Close down any events we may have */
|
|
for (i = 0; i < res->nEvents; i++)
|
|
{
|
|
/* only send DESTROY to successfully-initialized event procs */
|
|
if (res->events[i].resultInitialized)
|
|
{
|
|
PGEventResultDestroy evt;
|
|
|
|
evt.result = res;
|
|
(void) res->events[i].proc(PGEVT_RESULTDESTROY, &evt,
|
|
res->events[i].passThrough);
|
|
}
|
|
free(res->events[i].name);
|
|
}
|
|
|
|
free(res->events);
|
|
|
|
/* Free all the subsidiary blocks */
|
|
while ((block = res->curBlock) != NULL)
|
|
{
|
|
res->curBlock = block->next;
|
|
free(block);
|
|
}
|
|
|
|
/* Free the top-level tuple pointer array */
|
|
free(res->tuples);
|
|
|
|
/* zero out the pointer fields to catch programming errors */
|
|
res->attDescs = NULL;
|
|
res->tuples = NULL;
|
|
res->paramDescs = NULL;
|
|
res->errFields = NULL;
|
|
res->events = NULL;
|
|
res->nEvents = 0;
|
|
/* res->curBlock was zeroed out earlier */
|
|
|
|
/* Free the PGresult structure itself */
|
|
free(res);
|
|
}
|
|
|
|
/*
|
|
* Handy subroutine to deallocate any partially constructed async result.
|
|
*
|
|
* Any "next" result gets cleared too.
|
|
*/
|
|
void
|
|
pqClearAsyncResult(PGconn *conn)
|
|
{
|
|
PQclear(conn->result);
|
|
conn->result = NULL;
|
|
conn->error_result = false;
|
|
PQclear(conn->next_result);
|
|
conn->next_result = NULL;
|
|
}
|
|
|
|
/*
|
|
* pqSaveErrorResult -
|
|
* remember that we have an error condition
|
|
*
|
|
* In much of libpq, reporting an error just requires appending text to
|
|
* conn->errorMessage and returning a failure code to one's caller.
|
|
* Where returning a failure code is impractical, instead call this
|
|
* function to remember that an error needs to be reported.
|
|
*
|
|
* (It might seem that appending text to conn->errorMessage should be
|
|
* sufficient, but we can't rely on that working under out-of-memory
|
|
* conditions. The OOM hazard is also why we don't try to make a new
|
|
* PGresult right here.)
|
|
*/
|
|
void
|
|
pqSaveErrorResult(PGconn *conn)
|
|
{
|
|
/* Drop any pending result ... */
|
|
pqClearAsyncResult(conn);
|
|
/* ... and set flag to remember to make an error result later */
|
|
conn->error_result = true;
|
|
}
|
|
|
|
/*
|
|
* pqSaveWriteError -
|
|
* report a write failure
|
|
*
|
|
* As above, after appending conn->write_err_msg to whatever other error we
|
|
* have. This is used when we've detected a write failure and have exhausted
|
|
* our chances of reporting something else instead.
|
|
*/
|
|
static void
|
|
pqSaveWriteError(PGconn *conn)
|
|
{
|
|
/*
|
|
* If write_err_msg is null because of previous strdup failure, do what we
|
|
* can. (It's likely our machinations here will get OOM failures as well,
|
|
* but might as well try.)
|
|
*/
|
|
if (conn->write_err_msg)
|
|
{
|
|
appendPQExpBufferStr(&conn->errorMessage, conn->write_err_msg);
|
|
/* Avoid possibly appending the same message twice */
|
|
conn->write_err_msg[0] = '\0';
|
|
}
|
|
else
|
|
libpq_append_conn_error(conn, "write to server failed");
|
|
|
|
pqSaveErrorResult(conn);
|
|
}
|
|
|
|
/*
|
|
* pqPrepareAsyncResult -
|
|
* prepare the current async result object for return to the caller
|
|
*
|
|
* If there is not already an async result object, build an error object
|
|
* using whatever is in conn->errorMessage. In any case, clear the async
|
|
* result storage, and update our notion of how much error text has been
|
|
* returned to the application.
|
|
*
|
|
* Note that in no case (not even OOM) do we return NULL.
|
|
*/
|
|
PGresult *
|
|
pqPrepareAsyncResult(PGconn *conn)
|
|
{
|
|
PGresult *res;
|
|
|
|
res = conn->result;
|
|
if (res)
|
|
{
|
|
/*
|
|
* If the pre-existing result is an ERROR (presumably something
|
|
* received from the server), assume that it represents whatever is in
|
|
* conn->errorMessage, and advance errorReported.
|
|
*/
|
|
if (res->resultStatus == PGRES_FATAL_ERROR)
|
|
conn->errorReported = conn->errorMessage.len;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* We get here after internal-to-libpq errors. We should probably
|
|
* always have error_result = true, but if we don't, gin up some error
|
|
* text.
|
|
*/
|
|
if (!conn->error_result)
|
|
libpq_append_conn_error(conn, "no error text available");
|
|
|
|
/* Paranoia: be sure errorReported offset is sane */
|
|
if (conn->errorReported < 0 ||
|
|
conn->errorReported >= conn->errorMessage.len)
|
|
conn->errorReported = 0;
|
|
|
|
/*
|
|
* Make a PGresult struct for the error. We temporarily lie about the
|
|
* result status, so that PQmakeEmptyPGresult doesn't uselessly copy
|
|
* all of conn->errorMessage.
|
|
*/
|
|
res = PQmakeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
|
|
if (res)
|
|
{
|
|
/*
|
|
* Report whatever new error text we have, and advance
|
|
* errorReported.
|
|
*/
|
|
res->resultStatus = PGRES_FATAL_ERROR;
|
|
pqSetResultError(res, &conn->errorMessage, conn->errorReported);
|
|
conn->errorReported = conn->errorMessage.len;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Ouch, not enough memory for a PGresult. Fortunately, we have a
|
|
* card up our sleeve: we can use the static OOM_result. Casting
|
|
* away const here is a bit ugly, but it seems best to declare
|
|
* OOM_result as const, in hopes it will be allocated in read-only
|
|
* storage.
|
|
*/
|
|
res = unconstify(PGresult *, &OOM_result);
|
|
|
|
/*
|
|
* Don't advance errorReported. Perhaps we'll be able to report
|
|
* the text later.
|
|
*/
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Replace conn->result with next_result, if any. In the normal case
|
|
* there isn't a next result and we're just dropping ownership of the
|
|
* current result. In single-row mode this restores the situation to what
|
|
* it was before we created the current single-row result.
|
|
*/
|
|
conn->result = conn->next_result;
|
|
conn->error_result = false; /* next_result is never an error */
|
|
conn->next_result = NULL;
|
|
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* pqInternalNotice - produce an internally-generated notice message
|
|
*
|
|
* A format string and optional arguments can be passed. Note that we do
|
|
* libpq_gettext() here, so callers need not.
|
|
*
|
|
* The supplied text is taken as primary message (ie., it should not include
|
|
* a trailing newline, and should not be more than one line).
|
|
*/
|
|
void
|
|
pqInternalNotice(const PGNoticeHooks *hooks, const char *fmt,...)
|
|
{
|
|
char msgBuf[1024];
|
|
va_list args;
|
|
PGresult *res;
|
|
|
|
if (hooks->noticeRec == NULL)
|
|
return; /* nobody home to receive notice? */
|
|
|
|
/* Format the message */
|
|
va_start(args, fmt);
|
|
vsnprintf(msgBuf, sizeof(msgBuf), libpq_gettext(fmt), args);
|
|
va_end(args);
|
|
msgBuf[sizeof(msgBuf) - 1] = '\0'; /* make real sure it's terminated */
|
|
|
|
/* Make a PGresult to pass to the notice receiver */
|
|
res = PQmakeEmptyPGresult(NULL, PGRES_NONFATAL_ERROR);
|
|
if (!res)
|
|
return;
|
|
res->noticeHooks = *hooks;
|
|
|
|
/*
|
|
* Set up fields of notice.
|
|
*/
|
|
pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, msgBuf);
|
|
pqSaveMessageField(res, PG_DIAG_SEVERITY, libpq_gettext("NOTICE"));
|
|
pqSaveMessageField(res, PG_DIAG_SEVERITY_NONLOCALIZED, "NOTICE");
|
|
/* XXX should provide a SQLSTATE too? */
|
|
|
|
/*
|
|
* Result text is always just the primary message + newline. If we can't
|
|
* allocate it, substitute "out of memory", as in pqSetResultError.
|
|
*/
|
|
res->errMsg = (char *) pqResultAlloc(res, strlen(msgBuf) + 2, false);
|
|
if (res->errMsg)
|
|
sprintf(res->errMsg, "%s\n", msgBuf);
|
|
else
|
|
res->errMsg = libpq_gettext("out of memory\n");
|
|
|
|
/*
|
|
* Pass to receiver, then free it.
|
|
*/
|
|
res->noticeHooks.noticeRec(res->noticeHooks.noticeRecArg, res);
|
|
PQclear(res);
|
|
}
|
|
|
|
/*
|
|
* pqAddTuple
|
|
* add a row pointer to the PGresult structure, growing it if necessary
|
|
* Returns true if OK, false if an error prevented adding the row
|
|
*
|
|
* On error, *errmsgp can be set to an error string to be returned.
|
|
* If it is left NULL, the error is presumed to be "out of memory".
|
|
*/
|
|
static bool
|
|
pqAddTuple(PGresult *res, PGresAttValue *tup, const char **errmsgp)
|
|
{
|
|
if (res->ntups >= res->tupArrSize)
|
|
{
|
|
/*
|
|
* Try to grow the array.
|
|
*
|
|
* We can use realloc because shallow copying of the structure is
|
|
* okay. Note that the first time through, res->tuples is NULL. While
|
|
* ANSI says that realloc() should act like malloc() in that case,
|
|
* some old C libraries (like SunOS 4.1.x) coredump instead. On
|
|
* failure realloc is supposed to return NULL without damaging the
|
|
* existing allocation. Note that the positions beyond res->ntups are
|
|
* garbage, not necessarily NULL.
|
|
*/
|
|
int newSize;
|
|
PGresAttValue **newTuples;
|
|
|
|
/*
|
|
* Since we use integers for row numbers, we can't support more than
|
|
* INT_MAX rows. Make sure we allow that many, though.
|
|
*/
|
|
if (res->tupArrSize <= INT_MAX / 2)
|
|
newSize = (res->tupArrSize > 0) ? res->tupArrSize * 2 : 128;
|
|
else if (res->tupArrSize < INT_MAX)
|
|
newSize = INT_MAX;
|
|
else
|
|
{
|
|
*errmsgp = libpq_gettext("PGresult cannot support more than INT_MAX tuples");
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Also, on 32-bit platforms we could, in theory, overflow size_t even
|
|
* before newSize gets to INT_MAX. (In practice we'd doubtless hit
|
|
* OOM long before that, but let's check.)
|
|
*/
|
|
#if INT_MAX >= (SIZE_MAX / 2)
|
|
if (newSize > SIZE_MAX / sizeof(PGresAttValue *))
|
|
{
|
|
*errmsgp = libpq_gettext("size_t overflow");
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
if (res->tuples == NULL)
|
|
newTuples = (PGresAttValue **)
|
|
malloc(newSize * sizeof(PGresAttValue *));
|
|
else
|
|
newTuples = (PGresAttValue **)
|
|
realloc(res->tuples, newSize * sizeof(PGresAttValue *));
|
|
if (!newTuples)
|
|
return false; /* malloc or realloc failed */
|
|
res->memorySize +=
|
|
(newSize - res->tupArrSize) * sizeof(PGresAttValue *);
|
|
res->tupArrSize = newSize;
|
|
res->tuples = newTuples;
|
|
}
|
|
res->tuples[res->ntups] = tup;
|
|
res->ntups++;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* pqSaveMessageField - save one field of an error or notice message
|
|
*/
|
|
void
|
|
pqSaveMessageField(PGresult *res, char code, const char *value)
|
|
{
|
|
PGMessageField *pfield;
|
|
|
|
pfield = (PGMessageField *)
|
|
pqResultAlloc(res,
|
|
offsetof(PGMessageField, contents) +
|
|
strlen(value) + 1,
|
|
true);
|
|
if (!pfield)
|
|
return; /* out of memory? */
|
|
pfield->code = code;
|
|
strcpy(pfield->contents, value);
|
|
pfield->next = res->errFields;
|
|
res->errFields = pfield;
|
|
}
|
|
|
|
/*
|
|
* pqSaveParameterStatus - remember parameter status sent by backend
|
|
*/
|
|
void
|
|
pqSaveParameterStatus(PGconn *conn, const char *name, const char *value)
|
|
{
|
|
pgParameterStatus *pstatus;
|
|
pgParameterStatus *prev;
|
|
|
|
/*
|
|
* Forget any old information about the parameter
|
|
*/
|
|
for (pstatus = conn->pstatus, prev = NULL;
|
|
pstatus != NULL;
|
|
prev = pstatus, pstatus = pstatus->next)
|
|
{
|
|
if (strcmp(pstatus->name, name) == 0)
|
|
{
|
|
if (prev)
|
|
prev->next = pstatus->next;
|
|
else
|
|
conn->pstatus = pstatus->next;
|
|
free(pstatus); /* frees name and value strings too */
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Store new info as a single malloc block
|
|
*/
|
|
pstatus = (pgParameterStatus *) malloc(sizeof(pgParameterStatus) +
|
|
strlen(name) + strlen(value) + 2);
|
|
if (pstatus)
|
|
{
|
|
char *ptr;
|
|
|
|
ptr = ((char *) pstatus) + sizeof(pgParameterStatus);
|
|
pstatus->name = ptr;
|
|
strcpy(ptr, name);
|
|
ptr += strlen(name) + 1;
|
|
pstatus->value = ptr;
|
|
strcpy(ptr, value);
|
|
pstatus->next = conn->pstatus;
|
|
conn->pstatus = pstatus;
|
|
}
|
|
|
|
/*
|
|
* Save values of settings that are of interest to libpq in fields of the
|
|
* PGconn object. We keep client_encoding and standard_conforming_strings
|
|
* in static variables as well, so that PQescapeString and PQescapeBytea
|
|
* can behave somewhat sanely (at least in single-connection-using
|
|
* programs).
|
|
*/
|
|
if (strcmp(name, "client_encoding") == 0)
|
|
{
|
|
conn->client_encoding = pg_char_to_encoding(value);
|
|
/* if we don't recognize the encoding name, fall back to SQL_ASCII */
|
|
if (conn->client_encoding < 0)
|
|
conn->client_encoding = PG_SQL_ASCII;
|
|
static_client_encoding = conn->client_encoding;
|
|
}
|
|
else if (strcmp(name, "standard_conforming_strings") == 0)
|
|
{
|
|
conn->std_strings = (strcmp(value, "on") == 0);
|
|
static_std_strings = conn->std_strings;
|
|
}
|
|
else if (strcmp(name, "server_version") == 0)
|
|
{
|
|
/* We convert the server version to numeric form. */
|
|
int cnt;
|
|
int vmaj,
|
|
vmin,
|
|
vrev;
|
|
|
|
cnt = sscanf(value, "%d.%d.%d", &vmaj, &vmin, &vrev);
|
|
|
|
if (cnt == 3)
|
|
{
|
|
/* old style, e.g. 9.6.1 */
|
|
conn->sversion = (100 * vmaj + vmin) * 100 + vrev;
|
|
}
|
|
else if (cnt == 2)
|
|
{
|
|
if (vmaj >= 10)
|
|
{
|
|
/* new style, e.g. 10.1 */
|
|
conn->sversion = 100 * 100 * vmaj + vmin;
|
|
}
|
|
else
|
|
{
|
|
/* old style without minor version, e.g. 9.6devel */
|
|
conn->sversion = (100 * vmaj + vmin) * 100;
|
|
}
|
|
}
|
|
else if (cnt == 1)
|
|
{
|
|
/* new style without minor version, e.g. 10devel */
|
|
conn->sversion = 100 * 100 * vmaj;
|
|
}
|
|
else
|
|
conn->sversion = 0; /* unknown */
|
|
}
|
|
else if (strcmp(name, "default_transaction_read_only") == 0)
|
|
{
|
|
conn->default_transaction_read_only =
|
|
(strcmp(value, "on") == 0) ? PG_BOOL_YES : PG_BOOL_NO;
|
|
}
|
|
else if (strcmp(name, "in_hot_standby") == 0)
|
|
{
|
|
conn->in_hot_standby =
|
|
(strcmp(value, "on") == 0) ? PG_BOOL_YES : PG_BOOL_NO;
|
|
}
|
|
else if (strcmp(name, "scram_iterations") == 0)
|
|
{
|
|
conn->scram_sha_256_iterations = atoi(value);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* pqRowProcessor
|
|
* Add the received row to the current async result (conn->result).
|
|
* Returns 1 if OK, 0 if error occurred.
|
|
*
|
|
* On error, *errmsgp can be set to an error string to be returned.
|
|
* (Such a string should already be translated via libpq_gettext().)
|
|
* If it is left NULL, the error is presumed to be "out of memory".
|
|
*
|
|
* In single-row mode, we create a new result holding just the current row,
|
|
* stashing the previous result in conn->next_result so that it becomes
|
|
* active again after pqPrepareAsyncResult(). This allows the result metadata
|
|
* (column descriptions) to be carried forward to each result row.
|
|
*/
|
|
int
|
|
pqRowProcessor(PGconn *conn, const char **errmsgp)
|
|
{
|
|
PGresult *res = conn->result;
|
|
int nfields = res->numAttributes;
|
|
const PGdataValue *columns = conn->rowBuf;
|
|
PGresAttValue *tup;
|
|
int i;
|
|
|
|
/*
|
|
* In single-row mode, make a new PGresult that will hold just this one
|
|
* row; the original conn->result is left unchanged so that it can be used
|
|
* again as the template for future rows.
|
|
*/
|
|
if (conn->singleRowMode)
|
|
{
|
|
/* Copy everything that should be in the result at this point */
|
|
res = PQcopyResult(res,
|
|
PG_COPYRES_ATTRS | PG_COPYRES_EVENTS |
|
|
PG_COPYRES_NOTICEHOOKS);
|
|
if (!res)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Basically we just allocate space in the PGresult for each field and
|
|
* copy the data over.
|
|
*
|
|
* Note: on malloc failure, we return 0 leaving *errmsgp still NULL, which
|
|
* caller will take to mean "out of memory". This is preferable to trying
|
|
* to set up such a message here, because evidently there's not enough
|
|
* memory for gettext() to do anything.
|
|
*/
|
|
tup = (PGresAttValue *)
|
|
pqResultAlloc(res, nfields * sizeof(PGresAttValue), true);
|
|
if (tup == NULL)
|
|
goto fail;
|
|
|
|
for (i = 0; i < nfields; i++)
|
|
{
|
|
int clen = columns[i].len;
|
|
|
|
if (clen < 0)
|
|
{
|
|
/* null field */
|
|
tup[i].len = NULL_LEN;
|
|
tup[i].value = res->null_field;
|
|
}
|
|
else
|
|
{
|
|
bool isbinary = (res->attDescs[i].format != 0);
|
|
char *val;
|
|
|
|
val = (char *) pqResultAlloc(res, clen + 1, isbinary);
|
|
if (val == NULL)
|
|
goto fail;
|
|
|
|
/* copy and zero-terminate the data (even if it's binary) */
|
|
memcpy(val, columns[i].value, clen);
|
|
val[clen] = '\0';
|
|
|
|
tup[i].len = clen;
|
|
tup[i].value = val;
|
|
}
|
|
}
|
|
|
|
/* And add the tuple to the PGresult's tuple array */
|
|
if (!pqAddTuple(res, tup, errmsgp))
|
|
goto fail;
|
|
|
|
/*
|
|
* Success. In single-row mode, make the result available to the client
|
|
* immediately.
|
|
*/
|
|
if (conn->singleRowMode)
|
|
{
|
|
/* Change result status to special single-row value */
|
|
res->resultStatus = PGRES_SINGLE_TUPLE;
|
|
/* Stash old result for re-use later */
|
|
conn->next_result = conn->result;
|
|
conn->result = res;
|
|
/* And mark the result ready to return */
|
|
conn->asyncStatus = PGASYNC_READY_MORE;
|
|
}
|
|
|
|
return 1;
|
|
|
|
fail:
|
|
/* release locally allocated PGresult, if we made one */
|
|
if (res != conn->result)
|
|
PQclear(res);
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* pqAllocCmdQueueEntry
|
|
* Get a command queue entry for caller to fill.
|
|
*
|
|
* If the recycle queue has a free element, that is returned; if not, a
|
|
* fresh one is allocated. Caller is responsible for adding it to the
|
|
* command queue (pqAppendCmdQueueEntry) once the struct is filled in, or
|
|
* releasing the memory (pqRecycleCmdQueueEntry) if an error occurs.
|
|
*
|
|
* If allocation fails, sets the error message and returns NULL.
|
|
*/
|
|
static PGcmdQueueEntry *
|
|
pqAllocCmdQueueEntry(PGconn *conn)
|
|
{
|
|
PGcmdQueueEntry *entry;
|
|
|
|
if (conn->cmd_queue_recycle == NULL)
|
|
{
|
|
entry = (PGcmdQueueEntry *) malloc(sizeof(PGcmdQueueEntry));
|
|
if (entry == NULL)
|
|
{
|
|
libpq_append_conn_error(conn, "out of memory");
|
|
return NULL;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
entry = conn->cmd_queue_recycle;
|
|
conn->cmd_queue_recycle = entry->next;
|
|
}
|
|
entry->next = NULL;
|
|
entry->query = NULL;
|
|
|
|
return entry;
|
|
}
|
|
|
|
/*
|
|
* pqAppendCmdQueueEntry
|
|
* Append a caller-allocated entry to the command queue, and update
|
|
* conn->asyncStatus to account for it.
|
|
*
|
|
* The query itself must already have been put in the output buffer by the
|
|
* caller.
|
|
*/
|
|
static void
|
|
pqAppendCmdQueueEntry(PGconn *conn, PGcmdQueueEntry *entry)
|
|
{
|
|
Assert(entry->next == NULL);
|
|
|
|
if (conn->cmd_queue_head == NULL)
|
|
conn->cmd_queue_head = entry;
|
|
else
|
|
conn->cmd_queue_tail->next = entry;
|
|
|
|
conn->cmd_queue_tail = entry;
|
|
|
|
switch (conn->pipelineStatus)
|
|
{
|
|
case PQ_PIPELINE_OFF:
|
|
case PQ_PIPELINE_ON:
|
|
|
|
/*
|
|
* When not in pipeline aborted state, if there's a result ready
|
|
* to be consumed, let it be so (that is, don't change away from
|
|
* READY or READY_MORE); otherwise set us busy to wait for
|
|
* something to arrive from the server.
|
|
*/
|
|
if (conn->asyncStatus == PGASYNC_IDLE)
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
break;
|
|
|
|
case PQ_PIPELINE_ABORTED:
|
|
|
|
/*
|
|
* In aborted pipeline state, we don't expect anything from the
|
|
* server (since we don't send any queries that are queued).
|
|
* Therefore, if IDLE then do what PQgetResult would do to let
|
|
* itself consume commands from the queue; if we're in any other
|
|
* state, we don't have to do anything.
|
|
*/
|
|
if (conn->asyncStatus == PGASYNC_IDLE ||
|
|
conn->asyncStatus == PGASYNC_PIPELINE_IDLE)
|
|
pqPipelineProcessQueue(conn);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* pqRecycleCmdQueueEntry
|
|
* Push a command queue entry onto the freelist.
|
|
*/
|
|
static void
|
|
pqRecycleCmdQueueEntry(PGconn *conn, PGcmdQueueEntry *entry)
|
|
{
|
|
if (entry == NULL)
|
|
return;
|
|
|
|
/* recyclable entries should not have a follow-on command */
|
|
Assert(entry->next == NULL);
|
|
|
|
if (entry->query)
|
|
{
|
|
free(entry->query);
|
|
entry->query = NULL;
|
|
}
|
|
|
|
entry->next = conn->cmd_queue_recycle;
|
|
conn->cmd_queue_recycle = entry;
|
|
}
|
|
|
|
|
|
/*
|
|
* PQsendQuery
|
|
* Submit a query, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*
|
|
* PQsendQueryContinue is a non-exported version that behaves identically
|
|
* except that it doesn't reset conn->errorMessage.
|
|
*/
|
|
int
|
|
PQsendQuery(PGconn *conn, const char *query)
|
|
{
|
|
return PQsendQueryInternal(conn, query, true);
|
|
}
|
|
|
|
int
|
|
PQsendQueryContinue(PGconn *conn, const char *query)
|
|
{
|
|
return PQsendQueryInternal(conn, query, false);
|
|
}
|
|
|
|
static int
|
|
PQsendQueryInternal(PGconn *conn, const char *query, bool newQuery)
|
|
{
|
|
PGcmdQueueEntry *entry = NULL;
|
|
|
|
if (!PQsendQueryStart(conn, newQuery))
|
|
return 0;
|
|
|
|
/* check the argument */
|
|
if (!query)
|
|
{
|
|
libpq_append_conn_error(conn, "command string is a null pointer");
|
|
return 0;
|
|
}
|
|
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "%s not allowed in pipeline mode",
|
|
"PQsendQuery");
|
|
return 0;
|
|
}
|
|
|
|
entry = pqAllocCmdQueueEntry(conn);
|
|
if (entry == NULL)
|
|
return 0; /* error msg already set */
|
|
|
|
/* Send the query message(s) */
|
|
/* construct the outgoing Query message */
|
|
if (pqPutMsgStart(PqMsg_Query, conn) < 0 ||
|
|
pqPuts(query, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
{
|
|
/* error message should be set up already */
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
return 0;
|
|
}
|
|
|
|
/* remember we are using simple query protocol */
|
|
entry->queryclass = PGQUERY_SIMPLE;
|
|
/* and remember the query text too, if possible */
|
|
entry->query = strdup(query);
|
|
|
|
/*
|
|
* Give the data a push. In nonblock mode, don't complain if we're unable
|
|
* to send it all; PQgetResult() will do any additional flushing needed.
|
|
*/
|
|
if (pqFlush(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* OK, it's launched! */
|
|
pqAppendCmdQueueEntry(conn, entry);
|
|
|
|
return 1;
|
|
|
|
sendFailed:
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
/* error message should be set up already */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* PQsendQueryParams
|
|
* Like PQsendQuery, but use extended query protocol so we can pass parameters
|
|
*/
|
|
int
|
|
PQsendQueryParams(PGconn *conn,
|
|
const char *command,
|
|
int nParams,
|
|
const Oid *paramTypes,
|
|
const char *const *paramValues,
|
|
const int *paramLengths,
|
|
const int *paramFormats,
|
|
int resultFormat)
|
|
{
|
|
if (!PQsendQueryStart(conn, true))
|
|
return 0;
|
|
|
|
/* check the arguments */
|
|
if (!command)
|
|
{
|
|
libpq_append_conn_error(conn, "command string is a null pointer");
|
|
return 0;
|
|
}
|
|
if (nParams < 0 || nParams > PQ_QUERY_PARAM_MAX_LIMIT)
|
|
{
|
|
libpq_append_conn_error(conn, "number of parameters must be between 0 and %d",
|
|
PQ_QUERY_PARAM_MAX_LIMIT);
|
|
return 0;
|
|
}
|
|
|
|
return PQsendQueryGuts(conn,
|
|
command,
|
|
"", /* use unnamed statement */
|
|
nParams,
|
|
paramTypes,
|
|
paramValues,
|
|
paramLengths,
|
|
paramFormats,
|
|
resultFormat);
|
|
}
|
|
|
|
/*
|
|
* PQsendPrepare
|
|
* Submit a Parse message, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*/
|
|
int
|
|
PQsendPrepare(PGconn *conn,
|
|
const char *stmtName, const char *query,
|
|
int nParams, const Oid *paramTypes)
|
|
{
|
|
PGcmdQueueEntry *entry = NULL;
|
|
|
|
if (!PQsendQueryStart(conn, true))
|
|
return 0;
|
|
|
|
/* check the arguments */
|
|
if (!stmtName)
|
|
{
|
|
libpq_append_conn_error(conn, "statement name is a null pointer");
|
|
return 0;
|
|
}
|
|
if (!query)
|
|
{
|
|
libpq_append_conn_error(conn, "command string is a null pointer");
|
|
return 0;
|
|
}
|
|
if (nParams < 0 || nParams > PQ_QUERY_PARAM_MAX_LIMIT)
|
|
{
|
|
libpq_append_conn_error(conn, "number of parameters must be between 0 and %d",
|
|
PQ_QUERY_PARAM_MAX_LIMIT);
|
|
return 0;
|
|
}
|
|
|
|
entry = pqAllocCmdQueueEntry(conn);
|
|
if (entry == NULL)
|
|
return 0; /* error msg already set */
|
|
|
|
/* construct the Parse message */
|
|
if (pqPutMsgStart(PqMsg_Parse, conn) < 0 ||
|
|
pqPuts(stmtName, conn) < 0 ||
|
|
pqPuts(query, conn) < 0)
|
|
goto sendFailed;
|
|
|
|
if (nParams > 0 && paramTypes)
|
|
{
|
|
int i;
|
|
|
|
if (pqPutInt(nParams, 2, conn) < 0)
|
|
goto sendFailed;
|
|
for (i = 0; i < nParams; i++)
|
|
{
|
|
if (pqPutInt(paramTypes[i], 4, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (pqPutInt(0, 2, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
if (pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* Add a Sync, unless in pipeline mode. */
|
|
if (conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
if (pqPutMsgStart(PqMsg_Sync, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
/* remember we are doing just a Parse */
|
|
entry->queryclass = PGQUERY_PREPARE;
|
|
|
|
/* and remember the query text too, if possible */
|
|
/* if insufficient memory, query just winds up NULL */
|
|
entry->query = strdup(query);
|
|
|
|
/*
|
|
* Give the data a push (in pipeline mode, only if we're past the size
|
|
* threshold). In nonblock mode, don't complain if we're unable to send
|
|
* it all; PQgetResult() will do any additional flushing needed.
|
|
*/
|
|
if (pqPipelineFlush(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* OK, it's launched! */
|
|
pqAppendCmdQueueEntry(conn, entry);
|
|
|
|
return 1;
|
|
|
|
sendFailed:
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
/* error message should be set up already */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* PQsendQueryPrepared
|
|
* Like PQsendQuery, but execute a previously prepared statement,
|
|
* using extended query protocol so we can pass parameters
|
|
*/
|
|
int
|
|
PQsendQueryPrepared(PGconn *conn,
|
|
const char *stmtName,
|
|
int nParams,
|
|
const char *const *paramValues,
|
|
const int *paramLengths,
|
|
const int *paramFormats,
|
|
int resultFormat)
|
|
{
|
|
if (!PQsendQueryStart(conn, true))
|
|
return 0;
|
|
|
|
/* check the arguments */
|
|
if (!stmtName)
|
|
{
|
|
libpq_append_conn_error(conn, "statement name is a null pointer");
|
|
return 0;
|
|
}
|
|
if (nParams < 0 || nParams > PQ_QUERY_PARAM_MAX_LIMIT)
|
|
{
|
|
libpq_append_conn_error(conn, "number of parameters must be between 0 and %d",
|
|
PQ_QUERY_PARAM_MAX_LIMIT);
|
|
return 0;
|
|
}
|
|
|
|
return PQsendQueryGuts(conn,
|
|
NULL, /* no command to parse */
|
|
stmtName,
|
|
nParams,
|
|
NULL, /* no param types */
|
|
paramValues,
|
|
paramLengths,
|
|
paramFormats,
|
|
resultFormat);
|
|
}
|
|
|
|
/*
|
|
* PQsendQueryStart
|
|
* Common startup code for PQsendQuery and sibling routines
|
|
*/
|
|
static bool
|
|
PQsendQueryStart(PGconn *conn, bool newQuery)
|
|
{
|
|
if (!conn)
|
|
return false;
|
|
|
|
/*
|
|
* If this is the beginning of a query cycle, reset the error state.
|
|
* However, in pipeline mode with something already queued, the error
|
|
* buffer belongs to that command and we shouldn't clear it.
|
|
*/
|
|
if (newQuery && conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
/* Don't try to send if we know there's no live connection. */
|
|
if (conn->status != CONNECTION_OK)
|
|
{
|
|
libpq_append_conn_error(conn, "no connection to the server");
|
|
return false;
|
|
}
|
|
|
|
/* Can't send while already busy, either, unless enqueuing for later */
|
|
if (conn->asyncStatus != PGASYNC_IDLE &&
|
|
conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "another command is already in progress");
|
|
return false;
|
|
}
|
|
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
{
|
|
/*
|
|
* When enqueuing commands we don't change much of the connection
|
|
* state since it's already in use for the current command. The
|
|
* connection state will get updated when pqPipelineProcessQueue()
|
|
* advances to start processing the queued message.
|
|
*
|
|
* Just make sure we can safely enqueue given the current connection
|
|
* state. We can enqueue behind another queue item, or behind a
|
|
* non-queue command (one that sends its own sync), but we can't
|
|
* enqueue if the connection is in a copy state.
|
|
*/
|
|
switch (conn->asyncStatus)
|
|
{
|
|
case PGASYNC_IDLE:
|
|
case PGASYNC_PIPELINE_IDLE:
|
|
case PGASYNC_READY:
|
|
case PGASYNC_READY_MORE:
|
|
case PGASYNC_BUSY:
|
|
/* ok to queue */
|
|
break;
|
|
|
|
case PGASYNC_COPY_IN:
|
|
case PGASYNC_COPY_OUT:
|
|
case PGASYNC_COPY_BOTH:
|
|
libpq_append_conn_error(conn, "cannot queue commands during COPY");
|
|
return false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* This command's results will come in immediately. Initialize async
|
|
* result-accumulation state
|
|
*/
|
|
pqClearAsyncResult(conn);
|
|
|
|
/* reset single-row processing mode */
|
|
conn->singleRowMode = false;
|
|
}
|
|
|
|
/* ready to send command message */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* PQsendQueryGuts
|
|
* Common code for sending a query with extended query protocol
|
|
* PQsendQueryStart should be done already
|
|
*
|
|
* command may be NULL to indicate we use an already-prepared statement
|
|
*/
|
|
static int
|
|
PQsendQueryGuts(PGconn *conn,
|
|
const char *command,
|
|
const char *stmtName,
|
|
int nParams,
|
|
const Oid *paramTypes,
|
|
const char *const *paramValues,
|
|
const int *paramLengths,
|
|
const int *paramFormats,
|
|
int resultFormat)
|
|
{
|
|
int i;
|
|
PGcmdQueueEntry *entry;
|
|
|
|
entry = pqAllocCmdQueueEntry(conn);
|
|
if (entry == NULL)
|
|
return 0; /* error msg already set */
|
|
|
|
/*
|
|
* We will send Parse (if needed), Bind, Describe Portal, Execute, Sync
|
|
* (if not in pipeline mode), using specified statement name and the
|
|
* unnamed portal.
|
|
*/
|
|
|
|
if (command)
|
|
{
|
|
/* construct the Parse message */
|
|
if (pqPutMsgStart(PqMsg_Parse, conn) < 0 ||
|
|
pqPuts(stmtName, conn) < 0 ||
|
|
pqPuts(command, conn) < 0)
|
|
goto sendFailed;
|
|
if (nParams > 0 && paramTypes)
|
|
{
|
|
if (pqPutInt(nParams, 2, conn) < 0)
|
|
goto sendFailed;
|
|
for (i = 0; i < nParams; i++)
|
|
{
|
|
if (pqPutInt(paramTypes[i], 4, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (pqPutInt(0, 2, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
if (pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
/* Construct the Bind message */
|
|
if (pqPutMsgStart(PqMsg_Bind, conn) < 0 ||
|
|
pqPuts("", conn) < 0 ||
|
|
pqPuts(stmtName, conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* Send parameter formats */
|
|
if (nParams > 0 && paramFormats)
|
|
{
|
|
if (pqPutInt(nParams, 2, conn) < 0)
|
|
goto sendFailed;
|
|
for (i = 0; i < nParams; i++)
|
|
{
|
|
if (pqPutInt(paramFormats[i], 2, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (pqPutInt(0, 2, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
if (pqPutInt(nParams, 2, conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* Send parameters */
|
|
for (i = 0; i < nParams; i++)
|
|
{
|
|
if (paramValues && paramValues[i])
|
|
{
|
|
int nbytes;
|
|
|
|
if (paramFormats && paramFormats[i] != 0)
|
|
{
|
|
/* binary parameter */
|
|
if (paramLengths)
|
|
nbytes = paramLengths[i];
|
|
else
|
|
{
|
|
libpq_append_conn_error(conn, "length must be given for binary parameter");
|
|
goto sendFailed;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* text parameter, do not use paramLengths */
|
|
nbytes = strlen(paramValues[i]);
|
|
}
|
|
if (pqPutInt(nbytes, 4, conn) < 0 ||
|
|
pqPutnchar(paramValues[i], nbytes, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
else
|
|
{
|
|
/* take the param as NULL */
|
|
if (pqPutInt(-1, 4, conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
}
|
|
if (pqPutInt(1, 2, conn) < 0 ||
|
|
pqPutInt(resultFormat, 2, conn))
|
|
goto sendFailed;
|
|
if (pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* construct the Describe Portal message */
|
|
if (pqPutMsgStart(PqMsg_Describe, conn) < 0 ||
|
|
pqPutc('P', conn) < 0 ||
|
|
pqPuts("", conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* construct the Execute message */
|
|
if (pqPutMsgStart(PqMsg_Execute, conn) < 0 ||
|
|
pqPuts("", conn) < 0 ||
|
|
pqPutInt(0, 4, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* construct the Sync message if not in pipeline mode */
|
|
if (conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
if (pqPutMsgStart(PqMsg_Sync, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
/* remember we are using extended query protocol */
|
|
entry->queryclass = PGQUERY_EXTENDED;
|
|
|
|
/* and remember the query text too, if possible */
|
|
/* if insufficient memory, query just winds up NULL */
|
|
if (command)
|
|
entry->query = strdup(command);
|
|
|
|
/*
|
|
* Give the data a push (in pipeline mode, only if we're past the size
|
|
* threshold). In nonblock mode, don't complain if we're unable to send
|
|
* it all; PQgetResult() will do any additional flushing needed.
|
|
*/
|
|
if (pqPipelineFlush(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* OK, it's launched! */
|
|
pqAppendCmdQueueEntry(conn, entry);
|
|
|
|
return 1;
|
|
|
|
sendFailed:
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
/* error message should be set up already */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Select row-by-row processing mode
|
|
*/
|
|
int
|
|
PQsetSingleRowMode(PGconn *conn)
|
|
{
|
|
/*
|
|
* Only allow setting the flag when we have launched a query and not yet
|
|
* received any results.
|
|
*/
|
|
if (!conn)
|
|
return 0;
|
|
if (conn->asyncStatus != PGASYNC_BUSY)
|
|
return 0;
|
|
if (!conn->cmd_queue_head ||
|
|
(conn->cmd_queue_head->queryclass != PGQUERY_SIMPLE &&
|
|
conn->cmd_queue_head->queryclass != PGQUERY_EXTENDED))
|
|
return 0;
|
|
if (pgHavePendingResult(conn))
|
|
return 0;
|
|
|
|
/* OK, set flag */
|
|
conn->singleRowMode = true;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Consume any available input from the backend
|
|
* 0 return: some kind of trouble
|
|
* 1 return: no problem
|
|
*/
|
|
int
|
|
PQconsumeInput(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return 0;
|
|
|
|
/*
|
|
* for non-blocking connections try to flush the send-queue, otherwise we
|
|
* may never get a response for something that may not have already been
|
|
* sent because it's in our write buffer!
|
|
*/
|
|
if (pqIsnonblocking(conn))
|
|
{
|
|
if (pqFlush(conn) < 0)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Load more data, if available. We do this no matter what state we are
|
|
* in, since we are probably getting called because the application wants
|
|
* to get rid of a read-select condition. Note that we will NOT block
|
|
* waiting for more input.
|
|
*/
|
|
if (pqReadData(conn) < 0)
|
|
return 0;
|
|
|
|
/* Parsing of the data waits till later. */
|
|
return 1;
|
|
}
|
|
|
|
|
|
/*
|
|
* parseInput: if appropriate, parse input data from backend
|
|
* until input is exhausted or a stopping state is reached.
|
|
* Note that this function will NOT attempt to read more data from the backend.
|
|
*/
|
|
static void
|
|
parseInput(PGconn *conn)
|
|
{
|
|
pqParseInput3(conn);
|
|
}
|
|
|
|
/*
|
|
* PQisBusy
|
|
* Return true if PQgetResult would block waiting for input.
|
|
*/
|
|
|
|
int
|
|
PQisBusy(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return false;
|
|
|
|
/* Parse any available data, if our state permits. */
|
|
parseInput(conn);
|
|
|
|
/*
|
|
* PQgetResult will return immediately in all states except BUSY. Also,
|
|
* if we've detected read EOF and dropped the connection, we can expect
|
|
* that PQgetResult will fail immediately. Note that we do *not* check
|
|
* conn->write_failed here --- once that's become set, we know we have
|
|
* trouble, but we need to keep trying to read until we have a complete
|
|
* server message or detect read EOF.
|
|
*/
|
|
return conn->asyncStatus == PGASYNC_BUSY && conn->status != CONNECTION_BAD;
|
|
}
|
|
|
|
/*
|
|
* PQgetResult
|
|
* Get the next PGresult produced by a query. Returns NULL if no
|
|
* query work remains or an error has occurred (e.g. out of
|
|
* memory).
|
|
*
|
|
* In pipeline mode, once all the result of a query have been returned,
|
|
* PQgetResult returns NULL to let the user know that the next
|
|
* query is being processed. At the end of the pipeline, returns a
|
|
* result with PQresultStatus(result) == PGRES_PIPELINE_SYNC.
|
|
*/
|
|
PGresult *
|
|
PQgetResult(PGconn *conn)
|
|
{
|
|
PGresult *res;
|
|
|
|
if (!conn)
|
|
return NULL;
|
|
|
|
/* Parse any available data, if our state permits. */
|
|
parseInput(conn);
|
|
|
|
/* If not ready to return something, block until we are. */
|
|
while (conn->asyncStatus == PGASYNC_BUSY)
|
|
{
|
|
int flushResult;
|
|
|
|
/*
|
|
* If data remains unsent, send it. Else we might be waiting for the
|
|
* result of a command the backend hasn't even got yet.
|
|
*/
|
|
while ((flushResult = pqFlush(conn)) > 0)
|
|
{
|
|
if (pqWait(false, true, conn))
|
|
{
|
|
flushResult = -1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Wait for some more data, and load it. (Note: if the connection has
|
|
* been lost, pqWait should return immediately because the socket
|
|
* should be read-ready, either with the last server data or with an
|
|
* EOF indication. We expect therefore that this won't result in any
|
|
* undue delay in reporting a previous write failure.)
|
|
*/
|
|
if (flushResult ||
|
|
pqWait(true, false, conn) ||
|
|
pqReadData(conn) < 0)
|
|
{
|
|
/* Report the error saved by pqWait or pqReadData */
|
|
pqSaveErrorResult(conn);
|
|
conn->asyncStatus = PGASYNC_IDLE;
|
|
return pqPrepareAsyncResult(conn);
|
|
}
|
|
|
|
/* Parse it. */
|
|
parseInput(conn);
|
|
|
|
/*
|
|
* If we had a write error, but nothing above obtained a query result
|
|
* or detected a read error, report the write error.
|
|
*/
|
|
if (conn->write_failed && conn->asyncStatus == PGASYNC_BUSY)
|
|
{
|
|
pqSaveWriteError(conn);
|
|
conn->asyncStatus = PGASYNC_IDLE;
|
|
return pqPrepareAsyncResult(conn);
|
|
}
|
|
}
|
|
|
|
/* Return the appropriate thing. */
|
|
switch (conn->asyncStatus)
|
|
{
|
|
case PGASYNC_IDLE:
|
|
res = NULL; /* query is complete */
|
|
break;
|
|
case PGASYNC_PIPELINE_IDLE:
|
|
Assert(conn->pipelineStatus != PQ_PIPELINE_OFF);
|
|
|
|
/*
|
|
* We're about to return the NULL that terminates the round of
|
|
* results from the current query; prepare to send the results of
|
|
* the next query, if any, when we're called next. If there's no
|
|
* next element in the command queue, this gets us in IDLE state.
|
|
*/
|
|
pqPipelineProcessQueue(conn);
|
|
res = NULL; /* query is complete */
|
|
break;
|
|
|
|
case PGASYNC_READY:
|
|
res = pqPrepareAsyncResult(conn);
|
|
|
|
/* Advance the queue as appropriate */
|
|
pqCommandQueueAdvance(conn, false,
|
|
res->resultStatus == PGRES_PIPELINE_SYNC);
|
|
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
{
|
|
/*
|
|
* We're about to send the results of the current query. Set
|
|
* us idle now, and ...
|
|
*/
|
|
conn->asyncStatus = PGASYNC_PIPELINE_IDLE;
|
|
|
|
/*
|
|
* ... in cases when we're sending a pipeline-sync result,
|
|
* move queue processing forwards immediately, so that next
|
|
* time we're called, we're prepared to return the next result
|
|
* received from the server. In all other cases, leave the
|
|
* queue state change for next time, so that a terminating
|
|
* NULL result is sent.
|
|
*
|
|
* (In other words: we don't return a NULL after a pipeline
|
|
* sync.)
|
|
*/
|
|
if (res->resultStatus == PGRES_PIPELINE_SYNC)
|
|
pqPipelineProcessQueue(conn);
|
|
}
|
|
else
|
|
{
|
|
/* Set the state back to BUSY, allowing parsing to proceed. */
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
}
|
|
break;
|
|
case PGASYNC_READY_MORE:
|
|
res = pqPrepareAsyncResult(conn);
|
|
/* Set the state back to BUSY, allowing parsing to proceed. */
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
break;
|
|
case PGASYNC_COPY_IN:
|
|
res = getCopyResult(conn, PGRES_COPY_IN);
|
|
break;
|
|
case PGASYNC_COPY_OUT:
|
|
res = getCopyResult(conn, PGRES_COPY_OUT);
|
|
break;
|
|
case PGASYNC_COPY_BOTH:
|
|
res = getCopyResult(conn, PGRES_COPY_BOTH);
|
|
break;
|
|
default:
|
|
libpq_append_conn_error(conn, "unexpected asyncStatus: %d", (int) conn->asyncStatus);
|
|
pqSaveErrorResult(conn);
|
|
conn->asyncStatus = PGASYNC_IDLE; /* try to restore valid state */
|
|
res = pqPrepareAsyncResult(conn);
|
|
break;
|
|
}
|
|
|
|
/* Time to fire PGEVT_RESULTCREATE events, if there are any */
|
|
if (res && res->nEvents > 0)
|
|
(void) PQfireResultCreateEvents(conn, res);
|
|
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* getCopyResult
|
|
* Helper for PQgetResult: generate result for COPY-in-progress cases
|
|
*/
|
|
static PGresult *
|
|
getCopyResult(PGconn *conn, ExecStatusType copytype)
|
|
{
|
|
/*
|
|
* If the server connection has been lost, don't pretend everything is
|
|
* hunky-dory; instead return a PGRES_FATAL_ERROR result, and reset the
|
|
* asyncStatus to idle (corresponding to what we'd do if we'd detected I/O
|
|
* error in the earlier steps in PQgetResult). The text returned in the
|
|
* result is whatever is in conn->errorMessage; we hope that was filled
|
|
* with something relevant when the lost connection was detected.
|
|
*/
|
|
if (conn->status != CONNECTION_OK)
|
|
{
|
|
pqSaveErrorResult(conn);
|
|
conn->asyncStatus = PGASYNC_IDLE;
|
|
return pqPrepareAsyncResult(conn);
|
|
}
|
|
|
|
/* If we have an async result for the COPY, return that */
|
|
if (conn->result && conn->result->resultStatus == copytype)
|
|
return pqPrepareAsyncResult(conn);
|
|
|
|
/* Otherwise, invent a suitable PGresult */
|
|
return PQmakeEmptyPGresult(conn, copytype);
|
|
}
|
|
|
|
|
|
/*
|
|
* PQexec
|
|
* send a query to the backend and package up the result in a PGresult
|
|
*
|
|
* If the query was not even sent, return NULL; conn->errorMessage is set to
|
|
* a relevant message.
|
|
* If the query was sent, a new PGresult is returned (which could indicate
|
|
* either success or failure).
|
|
* The user is responsible for freeing the PGresult via PQclear()
|
|
* when done with it.
|
|
*/
|
|
PGresult *
|
|
PQexec(PGconn *conn, const char *query)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendQuery(conn, query))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQexecParams
|
|
* Like PQexec, but use extended query protocol so we can pass parameters
|
|
*/
|
|
PGresult *
|
|
PQexecParams(PGconn *conn,
|
|
const char *command,
|
|
int nParams,
|
|
const Oid *paramTypes,
|
|
const char *const *paramValues,
|
|
const int *paramLengths,
|
|
const int *paramFormats,
|
|
int resultFormat)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendQueryParams(conn, command,
|
|
nParams, paramTypes, paramValues, paramLengths,
|
|
paramFormats, resultFormat))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQprepare
|
|
* Creates a prepared statement by issuing a Parse message.
|
|
*
|
|
* If the query was not even sent, return NULL; conn->errorMessage is set to
|
|
* a relevant message.
|
|
* If the query was sent, a new PGresult is returned (which could indicate
|
|
* either success or failure).
|
|
* The user is responsible for freeing the PGresult via PQclear()
|
|
* when done with it.
|
|
*/
|
|
PGresult *
|
|
PQprepare(PGconn *conn,
|
|
const char *stmtName, const char *query,
|
|
int nParams, const Oid *paramTypes)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendPrepare(conn, stmtName, query, nParams, paramTypes))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQexecPrepared
|
|
* Like PQexec, but execute a previously prepared statement,
|
|
* using extended query protocol so we can pass parameters
|
|
*/
|
|
PGresult *
|
|
PQexecPrepared(PGconn *conn,
|
|
const char *stmtName,
|
|
int nParams,
|
|
const char *const *paramValues,
|
|
const int *paramLengths,
|
|
const int *paramFormats,
|
|
int resultFormat)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendQueryPrepared(conn, stmtName,
|
|
nParams, paramValues, paramLengths,
|
|
paramFormats, resultFormat))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* Common code for PQexec and sibling routines: prepare to send command
|
|
*/
|
|
static bool
|
|
PQexecStart(PGconn *conn)
|
|
{
|
|
PGresult *result;
|
|
|
|
if (!conn)
|
|
return false;
|
|
|
|
/*
|
|
* Since this is the beginning of a query cycle, reset the error state.
|
|
* However, in pipeline mode with something already queued, the error
|
|
* buffer belongs to that command and we shouldn't clear it.
|
|
*/
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "synchronous command execution functions are not allowed in pipeline mode");
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Silently discard any prior query result that application didn't eat.
|
|
* This is probably poor design, but it's here for backward compatibility.
|
|
*/
|
|
while ((result = PQgetResult(conn)) != NULL)
|
|
{
|
|
ExecStatusType resultStatus = result->resultStatus;
|
|
|
|
PQclear(result); /* only need its status */
|
|
if (resultStatus == PGRES_COPY_IN)
|
|
{
|
|
/* get out of a COPY IN state */
|
|
if (PQputCopyEnd(conn,
|
|
libpq_gettext("COPY terminated by new PQexec")) < 0)
|
|
return false;
|
|
/* keep waiting to swallow the copy's failure message */
|
|
}
|
|
else if (resultStatus == PGRES_COPY_OUT)
|
|
{
|
|
/*
|
|
* Get out of a COPY OUT state: we just switch back to BUSY and
|
|
* allow the remaining COPY data to be dropped on the floor.
|
|
*/
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
/* keep waiting to swallow the copy's completion message */
|
|
}
|
|
else if (resultStatus == PGRES_COPY_BOTH)
|
|
{
|
|
/* We don't allow PQexec during COPY BOTH */
|
|
libpq_append_conn_error(conn, "PQexec not allowed during COPY BOTH");
|
|
return false;
|
|
}
|
|
/* check for loss of connection, too */
|
|
if (conn->status == CONNECTION_BAD)
|
|
return false;
|
|
}
|
|
|
|
/* OK to send a command */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Common code for PQexec and sibling routines: wait for command result
|
|
*/
|
|
static PGresult *
|
|
PQexecFinish(PGconn *conn)
|
|
{
|
|
PGresult *result;
|
|
PGresult *lastResult;
|
|
|
|
/*
|
|
* For backwards compatibility, return the last result if there are more
|
|
* than one. (We used to have logic here to concatenate successive error
|
|
* messages, but now that happens automatically, since conn->errorMessage
|
|
* will continue to accumulate errors throughout this loop.)
|
|
*
|
|
* We have to stop if we see copy in/out/both, however. We will resume
|
|
* parsing after application performs the data transfer.
|
|
*
|
|
* Also stop if the connection is lost (else we'll loop infinitely).
|
|
*/
|
|
lastResult = NULL;
|
|
while ((result = PQgetResult(conn)) != NULL)
|
|
{
|
|
PQclear(lastResult);
|
|
lastResult = result;
|
|
if (result->resultStatus == PGRES_COPY_IN ||
|
|
result->resultStatus == PGRES_COPY_OUT ||
|
|
result->resultStatus == PGRES_COPY_BOTH ||
|
|
conn->status == CONNECTION_BAD)
|
|
break;
|
|
}
|
|
|
|
return lastResult;
|
|
}
|
|
|
|
/*
|
|
* PQdescribePrepared
|
|
* Obtain information about a previously prepared statement
|
|
*
|
|
* If the query was not even sent, return NULL; conn->errorMessage is set to
|
|
* a relevant message.
|
|
* If the query was sent, a new PGresult is returned (which could indicate
|
|
* either success or failure). On success, the PGresult contains status
|
|
* PGRES_COMMAND_OK, and its parameter and column-heading fields describe
|
|
* the statement's inputs and outputs respectively.
|
|
* The user is responsible for freeing the PGresult via PQclear()
|
|
* when done with it.
|
|
*/
|
|
PGresult *
|
|
PQdescribePrepared(PGconn *conn, const char *stmt)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendTypedCommand(conn, PqMsg_Describe, 'S', stmt))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQdescribePortal
|
|
* Obtain information about a previously created portal
|
|
*
|
|
* This is much like PQdescribePrepared, except that no parameter info is
|
|
* returned. Note that at the moment, libpq doesn't really expose portals
|
|
* to the client; but this can be used with a portal created by a SQL
|
|
* DECLARE CURSOR command.
|
|
*/
|
|
PGresult *
|
|
PQdescribePortal(PGconn *conn, const char *portal)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendTypedCommand(conn, PqMsg_Describe, 'P', portal))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQsendDescribePrepared
|
|
* Submit a Describe Statement command, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*/
|
|
int
|
|
PQsendDescribePrepared(PGconn *conn, const char *stmt)
|
|
{
|
|
return PQsendTypedCommand(conn, PqMsg_Describe, 'S', stmt);
|
|
}
|
|
|
|
/*
|
|
* PQsendDescribePortal
|
|
* Submit a Describe Portal command, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*/
|
|
int
|
|
PQsendDescribePortal(PGconn *conn, const char *portal)
|
|
{
|
|
return PQsendTypedCommand(conn, PqMsg_Describe, 'P', portal);
|
|
}
|
|
|
|
/*
|
|
* PQclosePrepared
|
|
* Close a previously prepared statement
|
|
*
|
|
* If the query was not even sent, return NULL; conn->errorMessage is set to
|
|
* a relevant message.
|
|
* If the query was sent, a new PGresult is returned (which could indicate
|
|
* either success or failure). On success, the PGresult contains status
|
|
* PGRES_COMMAND_OK. The user is responsible for freeing the PGresult via
|
|
* PQclear() when done with it.
|
|
*/
|
|
PGresult *
|
|
PQclosePrepared(PGconn *conn, const char *stmt)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendTypedCommand(conn, PqMsg_Close, 'S', stmt))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQclosePortal
|
|
* Close a previously created portal
|
|
*
|
|
* This is exactly like PQclosePrepared, but for portals. Note that at the
|
|
* moment, libpq doesn't really expose portals to the client; but this can be
|
|
* used with a portal created by a SQL DECLARE CURSOR command.
|
|
*/
|
|
PGresult *
|
|
PQclosePortal(PGconn *conn, const char *portal)
|
|
{
|
|
if (!PQexecStart(conn))
|
|
return NULL;
|
|
if (!PQsendTypedCommand(conn, PqMsg_Close, 'P', portal))
|
|
return NULL;
|
|
return PQexecFinish(conn);
|
|
}
|
|
|
|
/*
|
|
* PQsendClosePrepared
|
|
* Submit a Close Statement command, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*/
|
|
int
|
|
PQsendClosePrepared(PGconn *conn, const char *stmt)
|
|
{
|
|
return PQsendTypedCommand(conn, PqMsg_Close, 'S', stmt);
|
|
}
|
|
|
|
/*
|
|
* PQsendClosePortal
|
|
* Submit a Close Portal command, but don't wait for it to finish
|
|
*
|
|
* Returns: 1 if successfully submitted
|
|
* 0 if error (conn->errorMessage is set)
|
|
*/
|
|
int
|
|
PQsendClosePortal(PGconn *conn, const char *portal)
|
|
{
|
|
return PQsendTypedCommand(conn, PqMsg_Close, 'P', portal);
|
|
}
|
|
|
|
/*
|
|
* PQsendTypedCommand
|
|
* Common code to send a Describe or Close command
|
|
*
|
|
* Available options for "command" are
|
|
* PqMsg_Close for Close; or
|
|
* PqMsg_Describe for Describe.
|
|
*
|
|
* Available options for "type" are
|
|
* 'S' to run a command on a prepared statement; or
|
|
* 'P' to run a command on a portal.
|
|
*
|
|
* Returns 1 on success and 0 on failure.
|
|
*/
|
|
static int
|
|
PQsendTypedCommand(PGconn *conn, char command, char type, const char *target)
|
|
{
|
|
PGcmdQueueEntry *entry = NULL;
|
|
|
|
/* Treat null target as empty string */
|
|
if (!target)
|
|
target = "";
|
|
|
|
if (!PQsendQueryStart(conn, true))
|
|
return 0;
|
|
|
|
entry = pqAllocCmdQueueEntry(conn);
|
|
if (entry == NULL)
|
|
return 0; /* error msg already set */
|
|
|
|
/* construct the Close message */
|
|
if (pqPutMsgStart(command, conn) < 0 ||
|
|
pqPutc(type, conn) < 0 ||
|
|
pqPuts(target, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* construct the Sync message */
|
|
if (conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
if (pqPutMsgStart(PqMsg_Sync, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
/* remember if we are doing a Close or a Describe */
|
|
if (command == PqMsg_Close)
|
|
{
|
|
entry->queryclass = PGQUERY_CLOSE;
|
|
}
|
|
else if (command == PqMsg_Describe)
|
|
{
|
|
entry->queryclass = PGQUERY_DESCRIBE;
|
|
}
|
|
else
|
|
{
|
|
libpq_append_conn_error(conn, "unknown command type provided");
|
|
goto sendFailed;
|
|
}
|
|
|
|
/*
|
|
* Give the data a push (in pipeline mode, only if we're past the size
|
|
* threshold). In nonblock mode, don't complain if we're unable to send
|
|
* it all; PQgetResult() will do any additional flushing needed.
|
|
*/
|
|
if (pqPipelineFlush(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/* OK, it's launched! */
|
|
pqAppendCmdQueueEntry(conn, entry);
|
|
|
|
return 1;
|
|
|
|
sendFailed:
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
/* error message should be set up already */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* PQnotifies
|
|
* returns a PGnotify* structure of the latest async notification
|
|
* that has not yet been handled
|
|
*
|
|
* returns NULL, if there is currently
|
|
* no unhandled async notification from the backend
|
|
*
|
|
* the CALLER is responsible for FREE'ing the structure returned
|
|
*
|
|
* Note that this function does not read any new data from the socket;
|
|
* so usually, caller should call PQconsumeInput() first.
|
|
*/
|
|
PGnotify *
|
|
PQnotifies(PGconn *conn)
|
|
{
|
|
PGnotify *event;
|
|
|
|
if (!conn)
|
|
return NULL;
|
|
|
|
/* Parse any available data to see if we can extract NOTIFY messages. */
|
|
parseInput(conn);
|
|
|
|
event = conn->notifyHead;
|
|
if (event)
|
|
{
|
|
conn->notifyHead = event->next;
|
|
if (!conn->notifyHead)
|
|
conn->notifyTail = NULL;
|
|
event->next = NULL; /* don't let app see the internal state */
|
|
}
|
|
return event;
|
|
}
|
|
|
|
/*
|
|
* PQputCopyData - send some data to the backend during COPY IN or COPY BOTH
|
|
*
|
|
* Returns 1 if successful, 0 if data could not be sent (only possible
|
|
* in nonblock mode), or -1 if an error occurs.
|
|
*/
|
|
int
|
|
PQputCopyData(PGconn *conn, const char *buffer, int nbytes)
|
|
{
|
|
if (!conn)
|
|
return -1;
|
|
if (conn->asyncStatus != PGASYNC_COPY_IN &&
|
|
conn->asyncStatus != PGASYNC_COPY_BOTH)
|
|
{
|
|
libpq_append_conn_error(conn, "no COPY in progress");
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Process any NOTICE or NOTIFY messages that might be pending in the
|
|
* input buffer. Since the server might generate many notices during the
|
|
* COPY, we want to clean those out reasonably promptly to prevent
|
|
* indefinite expansion of the input buffer. (Note: the actual read of
|
|
* input data into the input buffer happens down inside pqSendSome, but
|
|
* it's not authorized to get rid of the data again.)
|
|
*/
|
|
parseInput(conn);
|
|
|
|
if (nbytes > 0)
|
|
{
|
|
/*
|
|
* Try to flush any previously sent data in preference to growing the
|
|
* output buffer. If we can't enlarge the buffer enough to hold the
|
|
* data, return 0 in the nonblock case, else hard error. (For
|
|
* simplicity, always assume 5 bytes of overhead.)
|
|
*/
|
|
if ((conn->outBufSize - conn->outCount - 5) < nbytes)
|
|
{
|
|
if (pqFlush(conn) < 0)
|
|
return -1;
|
|
if (pqCheckOutBufferSpace(conn->outCount + 5 + (size_t) nbytes,
|
|
conn))
|
|
return pqIsnonblocking(conn) ? 0 : -1;
|
|
}
|
|
/* Send the data (too simple to delegate to fe-protocol files) */
|
|
if (pqPutMsgStart(PqMsg_CopyData, conn) < 0 ||
|
|
pqPutnchar(buffer, nbytes, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
return -1;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* PQputCopyEnd - send EOF indication to the backend during COPY IN
|
|
*
|
|
* After calling this, use PQgetResult() to check command completion status.
|
|
*
|
|
* Returns 1 if successful, or -1 if an error occurs.
|
|
*/
|
|
int
|
|
PQputCopyEnd(PGconn *conn, const char *errormsg)
|
|
{
|
|
if (!conn)
|
|
return -1;
|
|
if (conn->asyncStatus != PGASYNC_COPY_IN &&
|
|
conn->asyncStatus != PGASYNC_COPY_BOTH)
|
|
{
|
|
libpq_append_conn_error(conn, "no COPY in progress");
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Send the COPY END indicator. This is simple enough that we don't
|
|
* bother delegating it to the fe-protocol files.
|
|
*/
|
|
if (errormsg)
|
|
{
|
|
/* Send COPY FAIL */
|
|
if (pqPutMsgStart(PqMsg_CopyFail, conn) < 0 ||
|
|
pqPuts(errormsg, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
return -1;
|
|
}
|
|
else
|
|
{
|
|
/* Send COPY DONE */
|
|
if (pqPutMsgStart(PqMsg_CopyDone, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* If we sent the COPY command in extended-query mode, we must issue a
|
|
* Sync as well.
|
|
*/
|
|
if (conn->cmd_queue_head &&
|
|
conn->cmd_queue_head->queryclass != PGQUERY_SIMPLE)
|
|
{
|
|
if (pqPutMsgStart(PqMsg_Sync, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
return -1;
|
|
}
|
|
|
|
/* Return to active duty */
|
|
if (conn->asyncStatus == PGASYNC_COPY_BOTH)
|
|
conn->asyncStatus = PGASYNC_COPY_OUT;
|
|
else
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
|
|
/* Try to flush data */
|
|
if (pqFlush(conn) < 0)
|
|
return -1;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* PQgetCopyData - read a row of data from the backend during COPY OUT
|
|
* or COPY BOTH
|
|
*
|
|
* If successful, sets *buffer to point to a malloc'd row of data, and
|
|
* returns row length (always > 0) as result.
|
|
* Returns 0 if no row available yet (only possible if async is true),
|
|
* -1 if end of copy (consult PQgetResult), or -2 if error (consult
|
|
* PQerrorMessage).
|
|
*/
|
|
int
|
|
PQgetCopyData(PGconn *conn, char **buffer, int async)
|
|
{
|
|
*buffer = NULL; /* for all failure cases */
|
|
if (!conn)
|
|
return -2;
|
|
if (conn->asyncStatus != PGASYNC_COPY_OUT &&
|
|
conn->asyncStatus != PGASYNC_COPY_BOTH)
|
|
{
|
|
libpq_append_conn_error(conn, "no COPY in progress");
|
|
return -2;
|
|
}
|
|
return pqGetCopyData3(conn, buffer, async);
|
|
}
|
|
|
|
/*
|
|
* PQgetline - gets a newline-terminated string from the backend.
|
|
*
|
|
* Chiefly here so that applications can use "COPY <rel> to stdout"
|
|
* and read the output string. Returns a null-terminated string in `buffer`.
|
|
*
|
|
* XXX this routine is now deprecated, because it can't handle binary data.
|
|
* If called during a COPY BINARY we return EOF.
|
|
*
|
|
* PQgetline reads up to `length`-1 characters (like fgets(3)) but strips
|
|
* the terminating \n (like gets(3)).
|
|
*
|
|
* CAUTION: the caller is responsible for detecting the end-of-copy signal
|
|
* (a line containing just "\.") when using this routine.
|
|
*
|
|
* RETURNS:
|
|
* EOF if error (eg, invalid arguments are given)
|
|
* 0 if EOL is reached (i.e., \n has been read)
|
|
* (this is required for backward-compatibility -- this
|
|
* routine used to always return EOF or 0, assuming that
|
|
* the line ended within `length` bytes.)
|
|
* 1 in other cases (i.e., the buffer was filled before \n is reached)
|
|
*/
|
|
int
|
|
PQgetline(PGconn *conn, char *buffer, int length)
|
|
{
|
|
if (!buffer || length <= 0)
|
|
return EOF;
|
|
*buffer = '\0';
|
|
/* length must be at least 3 to hold the \. terminator! */
|
|
if (length < 3)
|
|
return EOF;
|
|
|
|
if (!conn)
|
|
return EOF;
|
|
|
|
return pqGetline3(conn, buffer, length);
|
|
}
|
|
|
|
/*
|
|
* PQgetlineAsync - gets a COPY data row without blocking.
|
|
*
|
|
* This routine is for applications that want to do "COPY <rel> to stdout"
|
|
* asynchronously, that is without blocking. Having issued the COPY command
|
|
* and gotten a PGRES_COPY_OUT response, the app should call PQconsumeInput
|
|
* and this routine until the end-of-data signal is detected. Unlike
|
|
* PQgetline, this routine takes responsibility for detecting end-of-data.
|
|
*
|
|
* On each call, PQgetlineAsync will return data if a complete data row
|
|
* is available in libpq's input buffer. Otherwise, no data is returned
|
|
* until the rest of the row arrives.
|
|
*
|
|
* If -1 is returned, the end-of-data signal has been recognized (and removed
|
|
* from libpq's input buffer). The caller *must* next call PQendcopy and
|
|
* then return to normal processing.
|
|
*
|
|
* RETURNS:
|
|
* -1 if the end-of-copy-data marker has been recognized
|
|
* 0 if no data is available
|
|
* >0 the number of bytes returned.
|
|
*
|
|
* The data returned will not extend beyond a data-row boundary. If possible
|
|
* a whole row will be returned at one time. But if the buffer offered by
|
|
* the caller is too small to hold a row sent by the backend, then a partial
|
|
* data row will be returned. In text mode this can be detected by testing
|
|
* whether the last returned byte is '\n' or not.
|
|
*
|
|
* The returned data is *not* null-terminated.
|
|
*/
|
|
|
|
int
|
|
PQgetlineAsync(PGconn *conn, char *buffer, int bufsize)
|
|
{
|
|
if (!conn)
|
|
return -1;
|
|
|
|
return pqGetlineAsync3(conn, buffer, bufsize);
|
|
}
|
|
|
|
/*
|
|
* PQputline -- sends a string to the backend during COPY IN.
|
|
* Returns 0 if OK, EOF if not.
|
|
*
|
|
* This is deprecated primarily because the return convention doesn't allow
|
|
* caller to tell the difference between a hard error and a nonblock-mode
|
|
* send failure.
|
|
*/
|
|
int
|
|
PQputline(PGconn *conn, const char *string)
|
|
{
|
|
return PQputnbytes(conn, string, strlen(string));
|
|
}
|
|
|
|
/*
|
|
* PQputnbytes -- like PQputline, but buffer need not be null-terminated.
|
|
* Returns 0 if OK, EOF if not.
|
|
*/
|
|
int
|
|
PQputnbytes(PGconn *conn, const char *buffer, int nbytes)
|
|
{
|
|
if (PQputCopyData(conn, buffer, nbytes) > 0)
|
|
return 0;
|
|
else
|
|
return EOF;
|
|
}
|
|
|
|
/*
|
|
* PQendcopy
|
|
* After completing the data transfer portion of a copy in/out,
|
|
* the application must call this routine to finish the command protocol.
|
|
*
|
|
* This is deprecated; it's cleaner to use PQgetResult to get the transfer
|
|
* status.
|
|
*
|
|
* RETURNS:
|
|
* 0 on success
|
|
* 1 on failure
|
|
*/
|
|
int
|
|
PQendcopy(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return 0;
|
|
|
|
return pqEndcopy3(conn);
|
|
}
|
|
|
|
|
|
/* ----------------
|
|
* PQfn - Send a function call to the POSTGRES backend.
|
|
*
|
|
* conn : backend connection
|
|
* fnid : OID of function to be called
|
|
* result_buf : pointer to result buffer
|
|
* result_len : actual length of result is returned here
|
|
* result_is_int : If the result is an integer, this must be 1,
|
|
* otherwise this should be 0
|
|
* args : pointer to an array of function arguments
|
|
* (each has length, if integer, and value/pointer)
|
|
* nargs : # of arguments in args array.
|
|
*
|
|
* RETURNS
|
|
* PGresult with status = PGRES_COMMAND_OK if successful.
|
|
* *result_len is > 0 if there is a return value, 0 if not.
|
|
* PGresult with status = PGRES_FATAL_ERROR if backend returns an error.
|
|
* NULL on communications failure. conn->errorMessage will be set.
|
|
* ----------------
|
|
*/
|
|
|
|
PGresult *
|
|
PQfn(PGconn *conn,
|
|
int fnid,
|
|
int *result_buf,
|
|
int *result_len,
|
|
int result_is_int,
|
|
const PQArgBlock *args,
|
|
int nargs)
|
|
{
|
|
*result_len = 0;
|
|
|
|
if (!conn)
|
|
return NULL;
|
|
|
|
/*
|
|
* Since this is the beginning of a query cycle, reset the error state.
|
|
* However, in pipeline mode with something already queued, the error
|
|
* buffer belongs to that command and we shouldn't clear it.
|
|
*/
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "%s not allowed in pipeline mode", "PQfn");
|
|
return NULL;
|
|
}
|
|
|
|
if (conn->sock == PGINVALID_SOCKET || conn->asyncStatus != PGASYNC_IDLE ||
|
|
pgHavePendingResult(conn))
|
|
{
|
|
libpq_append_conn_error(conn, "connection in wrong state");
|
|
return NULL;
|
|
}
|
|
|
|
return pqFunctionCall3(conn, fnid,
|
|
result_buf, result_len,
|
|
result_is_int,
|
|
args, nargs);
|
|
}
|
|
|
|
/* ====== Pipeline mode support ======== */
|
|
|
|
/*
|
|
* PQenterPipelineMode
|
|
* Put an idle connection in pipeline mode.
|
|
*
|
|
* Returns 1 on success. On failure, errorMessage is set and 0 is returned.
|
|
*
|
|
* Commands submitted after this can be pipelined on the connection;
|
|
* there's no requirement to wait for one to finish before the next is
|
|
* dispatched.
|
|
*
|
|
* Queuing of a new query or syncing during COPY is not allowed.
|
|
*
|
|
* A set of commands is terminated by a PQpipelineSync. Multiple sync
|
|
* points can be established while in pipeline mode. Pipeline mode can
|
|
* be exited by calling PQexitPipelineMode() once all results are processed.
|
|
*
|
|
* This doesn't actually send anything on the wire, it just puts libpq
|
|
* into a state where it can pipeline work.
|
|
*/
|
|
int
|
|
PQenterPipelineMode(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return 0;
|
|
|
|
/* succeed with no action if already in pipeline mode */
|
|
if (conn->pipelineStatus != PQ_PIPELINE_OFF)
|
|
return 1;
|
|
|
|
if (conn->asyncStatus != PGASYNC_IDLE)
|
|
{
|
|
libpq_append_conn_error(conn, "cannot enter pipeline mode, connection not idle");
|
|
return 0;
|
|
}
|
|
|
|
conn->pipelineStatus = PQ_PIPELINE_ON;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* PQexitPipelineMode
|
|
* End pipeline mode and return to normal command mode.
|
|
*
|
|
* Returns 1 in success (pipeline mode successfully ended, or not in pipeline
|
|
* mode).
|
|
*
|
|
* Returns 0 if in pipeline mode and cannot be ended yet. Error message will
|
|
* be set.
|
|
*/
|
|
int
|
|
PQexitPipelineMode(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return 0;
|
|
|
|
if (conn->pipelineStatus == PQ_PIPELINE_OFF &&
|
|
(conn->asyncStatus == PGASYNC_IDLE ||
|
|
conn->asyncStatus == PGASYNC_PIPELINE_IDLE) &&
|
|
conn->cmd_queue_head == NULL)
|
|
return 1;
|
|
|
|
switch (conn->asyncStatus)
|
|
{
|
|
case PGASYNC_READY:
|
|
case PGASYNC_READY_MORE:
|
|
/* there are some uncollected results */
|
|
libpq_append_conn_error(conn, "cannot exit pipeline mode with uncollected results");
|
|
return 0;
|
|
|
|
case PGASYNC_BUSY:
|
|
libpq_append_conn_error(conn, "cannot exit pipeline mode while busy");
|
|
return 0;
|
|
|
|
case PGASYNC_IDLE:
|
|
case PGASYNC_PIPELINE_IDLE:
|
|
/* OK */
|
|
break;
|
|
|
|
case PGASYNC_COPY_IN:
|
|
case PGASYNC_COPY_OUT:
|
|
case PGASYNC_COPY_BOTH:
|
|
libpq_append_conn_error(conn, "cannot exit pipeline mode while in COPY");
|
|
}
|
|
|
|
/* still work to process */
|
|
if (conn->cmd_queue_head != NULL)
|
|
{
|
|
libpq_append_conn_error(conn, "cannot exit pipeline mode with uncollected results");
|
|
return 0;
|
|
}
|
|
|
|
conn->pipelineStatus = PQ_PIPELINE_OFF;
|
|
conn->asyncStatus = PGASYNC_IDLE;
|
|
|
|
/* Flush any pending data in out buffer */
|
|
if (pqFlush(conn) < 0)
|
|
return 0; /* error message is setup already */
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* pqCommandQueueAdvance
|
|
* Remove one query from the command queue, if appropriate.
|
|
*
|
|
* If we have received all results corresponding to the head element
|
|
* in the command queue, remove it.
|
|
*
|
|
* In simple query protocol we must not advance the command queue until the
|
|
* ReadyForQuery message has been received. This is because in simple mode a
|
|
* command can have multiple queries, and we must process result for all of
|
|
* them before moving on to the next command.
|
|
*
|
|
* Another consideration is synchronization during error processing in
|
|
* extended query protocol: we refuse to advance the queue past a SYNC queue
|
|
* element, unless the result we've received is also a SYNC. In particular
|
|
* this protects us from advancing when an error is received at an
|
|
* inappropriate moment.
|
|
*/
|
|
void
|
|
pqCommandQueueAdvance(PGconn *conn, bool isReadyForQuery, bool gotSync)
|
|
{
|
|
PGcmdQueueEntry *prevquery;
|
|
|
|
if (conn->cmd_queue_head == NULL)
|
|
return;
|
|
|
|
/*
|
|
* If processing a query of simple query protocol, we only advance the
|
|
* queue when we receive the ReadyForQuery message for it.
|
|
*/
|
|
if (conn->cmd_queue_head->queryclass == PGQUERY_SIMPLE && !isReadyForQuery)
|
|
return;
|
|
|
|
/*
|
|
* If we're waiting for a SYNC, don't advance the queue until we get one.
|
|
*/
|
|
if (conn->cmd_queue_head->queryclass == PGQUERY_SYNC && !gotSync)
|
|
return;
|
|
|
|
/* delink element from queue */
|
|
prevquery = conn->cmd_queue_head;
|
|
conn->cmd_queue_head = conn->cmd_queue_head->next;
|
|
|
|
/* If the queue is now empty, reset the tail too */
|
|
if (conn->cmd_queue_head == NULL)
|
|
conn->cmd_queue_tail = NULL;
|
|
|
|
/* and make the queue element recyclable */
|
|
prevquery->next = NULL;
|
|
pqRecycleCmdQueueEntry(conn, prevquery);
|
|
}
|
|
|
|
/*
|
|
* pqPipelineProcessQueue: subroutine for PQgetResult
|
|
* In pipeline mode, start processing the results of the next query in the queue.
|
|
*/
|
|
static void
|
|
pqPipelineProcessQueue(PGconn *conn)
|
|
{
|
|
switch (conn->asyncStatus)
|
|
{
|
|
case PGASYNC_COPY_IN:
|
|
case PGASYNC_COPY_OUT:
|
|
case PGASYNC_COPY_BOTH:
|
|
case PGASYNC_READY:
|
|
case PGASYNC_READY_MORE:
|
|
case PGASYNC_BUSY:
|
|
/* client still has to process current query or results */
|
|
return;
|
|
|
|
case PGASYNC_IDLE:
|
|
|
|
/*
|
|
* If we're in IDLE mode and there's some command in the queue,
|
|
* get us into PIPELINE_IDLE mode and process normally. Otherwise
|
|
* there's nothing for us to do.
|
|
*/
|
|
if (conn->cmd_queue_head != NULL)
|
|
{
|
|
conn->asyncStatus = PGASYNC_PIPELINE_IDLE;
|
|
break;
|
|
}
|
|
return;
|
|
|
|
case PGASYNC_PIPELINE_IDLE:
|
|
Assert(conn->pipelineStatus != PQ_PIPELINE_OFF);
|
|
/* next query please */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Reset single-row processing mode. (Client has to set it up for each
|
|
* query, if desired.)
|
|
*/
|
|
conn->singleRowMode = false;
|
|
|
|
/*
|
|
* If there are no further commands to process in the queue, get us in
|
|
* "real idle" mode now.
|
|
*/
|
|
if (conn->cmd_queue_head == NULL)
|
|
{
|
|
conn->asyncStatus = PGASYNC_IDLE;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Reset the error state. This and the next couple of steps correspond to
|
|
* what PQsendQueryStart didn't do for this query.
|
|
*/
|
|
pqClearConnErrorState(conn);
|
|
|
|
/* Initialize async result-accumulation state */
|
|
pqClearAsyncResult(conn);
|
|
|
|
if (conn->pipelineStatus == PQ_PIPELINE_ABORTED &&
|
|
conn->cmd_queue_head->queryclass != PGQUERY_SYNC)
|
|
{
|
|
/*
|
|
* In an aborted pipeline we don't get anything from the server for
|
|
* each result; we're just discarding commands from the queue until we
|
|
* get to the next sync from the server.
|
|
*
|
|
* The PGRES_PIPELINE_ABORTED results tell the client that its queries
|
|
* got aborted.
|
|
*/
|
|
conn->result = PQmakeEmptyPGresult(conn, PGRES_PIPELINE_ABORTED);
|
|
if (!conn->result)
|
|
{
|
|
libpq_append_conn_error(conn, "out of memory");
|
|
pqSaveErrorResult(conn);
|
|
return;
|
|
}
|
|
conn->asyncStatus = PGASYNC_READY;
|
|
}
|
|
else
|
|
{
|
|
/* allow parsing to continue */
|
|
conn->asyncStatus = PGASYNC_BUSY;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* PQpipelineSync
|
|
* Send a Sync message as part of a pipeline, and flush to server
|
|
*/
|
|
int
|
|
PQpipelineSync(PGconn *conn)
|
|
{
|
|
return pqPipelineSyncInternal(conn, true);
|
|
}
|
|
|
|
/*
|
|
* PQsendPipelineSync
|
|
* Send a Sync message as part of a pipeline, without flushing to server
|
|
*/
|
|
int
|
|
PQsendPipelineSync(PGconn *conn)
|
|
{
|
|
return pqPipelineSyncInternal(conn, false);
|
|
}
|
|
|
|
/*
|
|
* Workhorse function for PQpipelineSync and PQsendPipelineSync.
|
|
*
|
|
* immediate_flush controls if the flush happens immediately after sending the
|
|
* Sync message or not.
|
|
*/
|
|
static int
|
|
pqPipelineSyncInternal(PGconn *conn, bool immediate_flush)
|
|
{
|
|
PGcmdQueueEntry *entry;
|
|
|
|
if (!conn)
|
|
return 0;
|
|
|
|
if (conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "cannot send pipeline when not in pipeline mode");
|
|
return 0;
|
|
}
|
|
|
|
switch (conn->asyncStatus)
|
|
{
|
|
case PGASYNC_COPY_IN:
|
|
case PGASYNC_COPY_OUT:
|
|
case PGASYNC_COPY_BOTH:
|
|
/* should be unreachable */
|
|
appendPQExpBufferStr(&conn->errorMessage,
|
|
"internal error: cannot send pipeline while in COPY\n");
|
|
return 0;
|
|
case PGASYNC_READY:
|
|
case PGASYNC_READY_MORE:
|
|
case PGASYNC_BUSY:
|
|
case PGASYNC_IDLE:
|
|
case PGASYNC_PIPELINE_IDLE:
|
|
/* OK to send sync */
|
|
break;
|
|
}
|
|
|
|
entry = pqAllocCmdQueueEntry(conn);
|
|
if (entry == NULL)
|
|
return 0; /* error msg already set */
|
|
|
|
entry->queryclass = PGQUERY_SYNC;
|
|
entry->query = NULL;
|
|
|
|
/* construct the Sync message */
|
|
if (pqPutMsgStart(PqMsg_Sync, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
goto sendFailed;
|
|
|
|
/*
|
|
* Give the data a push. In nonblock mode, don't complain if we're unable
|
|
* to send it all; PQgetResult() will do any additional flushing needed.
|
|
* If immediate_flush is disabled, the data is pushed if we are past the
|
|
* size threshold.
|
|
*/
|
|
if (immediate_flush)
|
|
{
|
|
if (pqFlush(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
else
|
|
{
|
|
if (pqPipelineFlush(conn) < 0)
|
|
goto sendFailed;
|
|
}
|
|
|
|
/* OK, it's launched! */
|
|
pqAppendCmdQueueEntry(conn, entry);
|
|
|
|
return 1;
|
|
|
|
sendFailed:
|
|
pqRecycleCmdQueueEntry(conn, entry);
|
|
/* error message should be set up already */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* PQsendFlushRequest
|
|
* Send request for server to flush its buffer. Useful in pipeline
|
|
* mode when a sync point is not desired.
|
|
*/
|
|
int
|
|
PQsendFlushRequest(PGconn *conn)
|
|
{
|
|
if (!conn)
|
|
return 0;
|
|
|
|
/* Don't try to send if we know there's no live connection. */
|
|
if (conn->status != CONNECTION_OK)
|
|
{
|
|
libpq_append_conn_error(conn, "no connection to the server");
|
|
return 0;
|
|
}
|
|
|
|
/* Can't send while already busy, either, unless enqueuing for later */
|
|
if (conn->asyncStatus != PGASYNC_IDLE &&
|
|
conn->pipelineStatus == PQ_PIPELINE_OFF)
|
|
{
|
|
libpq_append_conn_error(conn, "another command is already in progress");
|
|
return 0;
|
|
}
|
|
|
|
if (pqPutMsgStart(PqMsg_Flush, conn) < 0 ||
|
|
pqPutMsgEnd(conn) < 0)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Give the data a push (in pipeline mode, only if we're past the size
|
|
* threshold). In nonblock mode, don't complain if we're unable to send
|
|
* it all; PQgetResult() will do any additional flushing needed.
|
|
*/
|
|
if (pqPipelineFlush(conn) < 0)
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* ====== accessor funcs for PGresult ======== */
|
|
|
|
ExecStatusType
|
|
PQresultStatus(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return PGRES_FATAL_ERROR;
|
|
return res->resultStatus;
|
|
}
|
|
|
|
char *
|
|
PQresStatus(ExecStatusType status)
|
|
{
|
|
if ((unsigned int) status >= lengthof(pgresStatus))
|
|
return libpq_gettext("invalid ExecStatusType code");
|
|
return pgresStatus[status];
|
|
}
|
|
|
|
char *
|
|
PQresultErrorMessage(const PGresult *res)
|
|
{
|
|
if (!res || !res->errMsg)
|
|
return "";
|
|
return res->errMsg;
|
|
}
|
|
|
|
char *
|
|
PQresultVerboseErrorMessage(const PGresult *res,
|
|
PGVerbosity verbosity,
|
|
PGContextVisibility show_context)
|
|
{
|
|
PQExpBufferData workBuf;
|
|
|
|
/*
|
|
* Because the caller is expected to free the result string, we must
|
|
* strdup any constant result. We use plain strdup and document that
|
|
* callers should expect NULL if out-of-memory.
|
|
*/
|
|
if (!res ||
|
|
(res->resultStatus != PGRES_FATAL_ERROR &&
|
|
res->resultStatus != PGRES_NONFATAL_ERROR))
|
|
return strdup(libpq_gettext("PGresult is not an error result\n"));
|
|
|
|
initPQExpBuffer(&workBuf);
|
|
|
|
pqBuildErrorMessage3(&workBuf, res, verbosity, show_context);
|
|
|
|
/* If insufficient memory to format the message, fail cleanly */
|
|
if (PQExpBufferDataBroken(workBuf))
|
|
{
|
|
termPQExpBuffer(&workBuf);
|
|
return strdup(libpq_gettext("out of memory\n"));
|
|
}
|
|
|
|
return workBuf.data;
|
|
}
|
|
|
|
char *
|
|
PQresultErrorField(const PGresult *res, int fieldcode)
|
|
{
|
|
PGMessageField *pfield;
|
|
|
|
if (!res)
|
|
return NULL;
|
|
for (pfield = res->errFields; pfield != NULL; pfield = pfield->next)
|
|
{
|
|
if (pfield->code == fieldcode)
|
|
return pfield->contents;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
int
|
|
PQntuples(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return 0;
|
|
return res->ntups;
|
|
}
|
|
|
|
int
|
|
PQnfields(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return 0;
|
|
return res->numAttributes;
|
|
}
|
|
|
|
int
|
|
PQbinaryTuples(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return 0;
|
|
return res->binary;
|
|
}
|
|
|
|
/*
|
|
* Helper routines to range-check field numbers and tuple numbers.
|
|
* Return true if OK, false if not
|
|
*/
|
|
|
|
static int
|
|
check_field_number(const PGresult *res, int field_num)
|
|
{
|
|
if (!res)
|
|
return false; /* no way to display error message... */
|
|
if (field_num < 0 || field_num >= res->numAttributes)
|
|
{
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"column number %d is out of range 0..%d",
|
|
field_num, res->numAttributes - 1);
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static int
|
|
check_tuple_field_number(const PGresult *res,
|
|
int tup_num, int field_num)
|
|
{
|
|
if (!res)
|
|
return false; /* no way to display error message... */
|
|
if (tup_num < 0 || tup_num >= res->ntups)
|
|
{
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"row number %d is out of range 0..%d",
|
|
tup_num, res->ntups - 1);
|
|
return false;
|
|
}
|
|
if (field_num < 0 || field_num >= res->numAttributes)
|
|
{
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"column number %d is out of range 0..%d",
|
|
field_num, res->numAttributes - 1);
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static int
|
|
check_param_number(const PGresult *res, int param_num)
|
|
{
|
|
if (!res)
|
|
return false; /* no way to display error message... */
|
|
if (param_num < 0 || param_num >= res->numParameters)
|
|
{
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"parameter number %d is out of range 0..%d",
|
|
param_num, res->numParameters - 1);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* returns NULL if the field_num is invalid
|
|
*/
|
|
char *
|
|
PQfname(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return NULL;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].name;
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* PQfnumber: find column number given column name
|
|
*
|
|
* The column name is parsed as if it were in a SQL statement, including
|
|
* case-folding and double-quote processing. But note a possible gotcha:
|
|
* downcasing in the frontend might follow different locale rules than
|
|
* downcasing in the backend...
|
|
*
|
|
* Returns -1 if no match. In the present backend it is also possible
|
|
* to have multiple matches, in which case the first one is found.
|
|
*/
|
|
int
|
|
PQfnumber(const PGresult *res, const char *field_name)
|
|
{
|
|
char *field_case;
|
|
bool in_quotes;
|
|
bool all_lower = true;
|
|
const char *iptr;
|
|
char *optr;
|
|
int i;
|
|
|
|
if (!res)
|
|
return -1;
|
|
|
|
/*
|
|
* Note: it is correct to reject a zero-length input string; the proper
|
|
* input to match a zero-length field name would be "".
|
|
*/
|
|
if (field_name == NULL ||
|
|
field_name[0] == '\0' ||
|
|
res->attDescs == NULL)
|
|
return -1;
|
|
|
|
/*
|
|
* Check if we can avoid the strdup() and related work because the
|
|
* passed-in string wouldn't be changed before we do the check anyway.
|
|
*/
|
|
for (iptr = field_name; *iptr; iptr++)
|
|
{
|
|
char c = *iptr;
|
|
|
|
if (c == '"' || c != pg_tolower((unsigned char) c))
|
|
{
|
|
all_lower = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (all_lower)
|
|
for (i = 0; i < res->numAttributes; i++)
|
|
if (strcmp(field_name, res->attDescs[i].name) == 0)
|
|
return i;
|
|
|
|
/* Fall through to the normal check if that didn't work out. */
|
|
|
|
/*
|
|
* Note: this code will not reject partially quoted strings, eg
|
|
* foo"BAR"foo will become fooBARfoo when it probably ought to be an error
|
|
* condition.
|
|
*/
|
|
field_case = strdup(field_name);
|
|
if (field_case == NULL)
|
|
return -1; /* grotty */
|
|
|
|
in_quotes = false;
|
|
optr = field_case;
|
|
for (iptr = field_case; *iptr; iptr++)
|
|
{
|
|
char c = *iptr;
|
|
|
|
if (in_quotes)
|
|
{
|
|
if (c == '"')
|
|
{
|
|
if (iptr[1] == '"')
|
|
{
|
|
/* doubled quotes become a single quote */
|
|
*optr++ = '"';
|
|
iptr++;
|
|
}
|
|
else
|
|
in_quotes = false;
|
|
}
|
|
else
|
|
*optr++ = c;
|
|
}
|
|
else if (c == '"')
|
|
in_quotes = true;
|
|
else
|
|
{
|
|
c = pg_tolower((unsigned char) c);
|
|
*optr++ = c;
|
|
}
|
|
}
|
|
*optr = '\0';
|
|
|
|
for (i = 0; i < res->numAttributes; i++)
|
|
{
|
|
if (strcmp(field_case, res->attDescs[i].name) == 0)
|
|
{
|
|
free(field_case);
|
|
return i;
|
|
}
|
|
}
|
|
free(field_case);
|
|
return -1;
|
|
}
|
|
|
|
Oid
|
|
PQftable(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return InvalidOid;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].tableid;
|
|
else
|
|
return InvalidOid;
|
|
}
|
|
|
|
int
|
|
PQftablecol(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return 0;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].columnid;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
PQfformat(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return 0;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].format;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
Oid
|
|
PQftype(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return InvalidOid;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].typid;
|
|
else
|
|
return InvalidOid;
|
|
}
|
|
|
|
int
|
|
PQfsize(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return 0;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].typlen;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
PQfmod(const PGresult *res, int field_num)
|
|
{
|
|
if (!check_field_number(res, field_num))
|
|
return 0;
|
|
if (res->attDescs)
|
|
return res->attDescs[field_num].atttypmod;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
char *
|
|
PQcmdStatus(PGresult *res)
|
|
{
|
|
if (!res)
|
|
return NULL;
|
|
return res->cmdStatus;
|
|
}
|
|
|
|
/*
|
|
* PQoidStatus -
|
|
* if the last command was an INSERT, return the oid string
|
|
* if not, return ""
|
|
*/
|
|
char *
|
|
PQoidStatus(const PGresult *res)
|
|
{
|
|
/*
|
|
* This must be enough to hold the result. Don't laugh, this is better
|
|
* than what this function used to do.
|
|
*/
|
|
static char buf[24];
|
|
|
|
size_t len;
|
|
|
|
if (!res || strncmp(res->cmdStatus, "INSERT ", 7) != 0)
|
|
return "";
|
|
|
|
len = strspn(res->cmdStatus + 7, "0123456789");
|
|
if (len > sizeof(buf) - 1)
|
|
len = sizeof(buf) - 1;
|
|
memcpy(buf, res->cmdStatus + 7, len);
|
|
buf[len] = '\0';
|
|
|
|
return buf;
|
|
}
|
|
|
|
/*
|
|
* PQoidValue -
|
|
* a perhaps preferable form of the above which just returns
|
|
* an Oid type
|
|
*/
|
|
Oid
|
|
PQoidValue(const PGresult *res)
|
|
{
|
|
char *endptr = NULL;
|
|
unsigned long result;
|
|
|
|
if (!res ||
|
|
strncmp(res->cmdStatus, "INSERT ", 7) != 0 ||
|
|
res->cmdStatus[7] < '0' ||
|
|
res->cmdStatus[7] > '9')
|
|
return InvalidOid;
|
|
|
|
result = strtoul(res->cmdStatus + 7, &endptr, 10);
|
|
|
|
if (!endptr || (*endptr != ' ' && *endptr != '\0'))
|
|
return InvalidOid;
|
|
else
|
|
return (Oid) result;
|
|
}
|
|
|
|
|
|
/*
|
|
* PQcmdTuples -
|
|
* If the last command was INSERT/UPDATE/DELETE/MERGE/MOVE/FETCH/COPY,
|
|
* return a string containing the number of inserted/affected tuples.
|
|
* If not, return "".
|
|
*
|
|
* XXX: this should probably return an int
|
|
*/
|
|
char *
|
|
PQcmdTuples(PGresult *res)
|
|
{
|
|
char *p,
|
|
*c;
|
|
|
|
if (!res)
|
|
return "";
|
|
|
|
if (strncmp(res->cmdStatus, "INSERT ", 7) == 0)
|
|
{
|
|
p = res->cmdStatus + 7;
|
|
/* INSERT: skip oid and space */
|
|
while (*p && *p != ' ')
|
|
p++;
|
|
if (*p == 0)
|
|
goto interpret_error; /* no space? */
|
|
p++;
|
|
}
|
|
else if (strncmp(res->cmdStatus, "SELECT ", 7) == 0 ||
|
|
strncmp(res->cmdStatus, "DELETE ", 7) == 0 ||
|
|
strncmp(res->cmdStatus, "UPDATE ", 7) == 0)
|
|
p = res->cmdStatus + 7;
|
|
else if (strncmp(res->cmdStatus, "FETCH ", 6) == 0 ||
|
|
strncmp(res->cmdStatus, "MERGE ", 6) == 0)
|
|
p = res->cmdStatus + 6;
|
|
else if (strncmp(res->cmdStatus, "MOVE ", 5) == 0 ||
|
|
strncmp(res->cmdStatus, "COPY ", 5) == 0)
|
|
p = res->cmdStatus + 5;
|
|
else
|
|
return "";
|
|
|
|
/* check that we have an integer (at least one digit, nothing else) */
|
|
for (c = p; *c; c++)
|
|
{
|
|
if (!isdigit((unsigned char) *c))
|
|
goto interpret_error;
|
|
}
|
|
if (c == p)
|
|
goto interpret_error;
|
|
|
|
return p;
|
|
|
|
interpret_error:
|
|
pqInternalNotice(&res->noticeHooks,
|
|
"could not interpret result from server: %s",
|
|
res->cmdStatus);
|
|
return "";
|
|
}
|
|
|
|
/*
|
|
* PQgetvalue:
|
|
* return the value of field 'field_num' of row 'tup_num'
|
|
*/
|
|
char *
|
|
PQgetvalue(const PGresult *res, int tup_num, int field_num)
|
|
{
|
|
if (!check_tuple_field_number(res, tup_num, field_num))
|
|
return NULL;
|
|
return res->tuples[tup_num][field_num].value;
|
|
}
|
|
|
|
/* PQgetlength:
|
|
* returns the actual length of a field value in bytes.
|
|
*/
|
|
int
|
|
PQgetlength(const PGresult *res, int tup_num, int field_num)
|
|
{
|
|
if (!check_tuple_field_number(res, tup_num, field_num))
|
|
return 0;
|
|
if (res->tuples[tup_num][field_num].len != NULL_LEN)
|
|
return res->tuples[tup_num][field_num].len;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* PQgetisnull:
|
|
* returns the null status of a field value.
|
|
*/
|
|
int
|
|
PQgetisnull(const PGresult *res, int tup_num, int field_num)
|
|
{
|
|
if (!check_tuple_field_number(res, tup_num, field_num))
|
|
return 1; /* pretend it is null */
|
|
if (res->tuples[tup_num][field_num].len == NULL_LEN)
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* PQnparams:
|
|
* returns the number of input parameters of a prepared statement.
|
|
*/
|
|
int
|
|
PQnparams(const PGresult *res)
|
|
{
|
|
if (!res)
|
|
return 0;
|
|
return res->numParameters;
|
|
}
|
|
|
|
/* PQparamtype:
|
|
* returns type Oid of the specified statement parameter.
|
|
*/
|
|
Oid
|
|
PQparamtype(const PGresult *res, int param_num)
|
|
{
|
|
if (!check_param_number(res, param_num))
|
|
return InvalidOid;
|
|
if (res->paramDescs)
|
|
return res->paramDescs[param_num].typid;
|
|
else
|
|
return InvalidOid;
|
|
}
|
|
|
|
|
|
/* PQsetnonblocking:
|
|
* sets the PGconn's database connection non-blocking if the arg is true
|
|
* or makes it blocking if the arg is false, this will not protect
|
|
* you from PQexec(), you'll only be safe when using the non-blocking API.
|
|
* Needs to be called only on a connected database connection.
|
|
*/
|
|
int
|
|
PQsetnonblocking(PGconn *conn, int arg)
|
|
{
|
|
bool barg;
|
|
|
|
if (!conn || conn->status == CONNECTION_BAD)
|
|
return -1;
|
|
|
|
barg = (arg ? true : false);
|
|
|
|
/* early out if the socket is already in the state requested */
|
|
if (barg == conn->nonblocking)
|
|
return 0;
|
|
|
|
/*
|
|
* to guarantee constancy for flushing/query/result-polling behavior we
|
|
* need to flush the send queue at this point in order to guarantee proper
|
|
* behavior. this is ok because either they are making a transition _from_
|
|
* or _to_ blocking mode, either way we can block them.
|
|
*
|
|
* Clear error state in case pqFlush adds to it, unless we're actively
|
|
* pipelining, in which case it seems best not to.
|
|
*/
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
/* if we are going from blocking to non-blocking flush here */
|
|
if (pqFlush(conn))
|
|
return -1;
|
|
|
|
conn->nonblocking = barg;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* return the blocking status of the database connection
|
|
* true == nonblocking, false == blocking
|
|
*/
|
|
int
|
|
PQisnonblocking(const PGconn *conn)
|
|
{
|
|
if (!conn || conn->status == CONNECTION_BAD)
|
|
return false;
|
|
return pqIsnonblocking(conn);
|
|
}
|
|
|
|
/* libpq is thread-safe? */
|
|
int
|
|
PQisthreadsafe(void)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
|
|
/* try to force data out, really only useful for non-blocking users */
|
|
int
|
|
PQflush(PGconn *conn)
|
|
{
|
|
if (!conn || conn->status == CONNECTION_BAD)
|
|
return -1;
|
|
return pqFlush(conn);
|
|
}
|
|
|
|
/*
|
|
* pqPipelineFlush
|
|
*
|
|
* In pipeline mode, data will be flushed only when the out buffer reaches the
|
|
* threshold value. In non-pipeline mode, it behaves as stock pqFlush.
|
|
*
|
|
* Returns 0 on success.
|
|
*/
|
|
static int
|
|
pqPipelineFlush(PGconn *conn)
|
|
{
|
|
if ((conn->pipelineStatus != PQ_PIPELINE_ON) ||
|
|
(conn->outCount >= OUTBUFFER_THRESHOLD))
|
|
return pqFlush(conn);
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* PQfreemem - safely frees memory allocated
|
|
*
|
|
* Needed mostly by Win32, unless multithreaded DLL (/MD in VC6)
|
|
* Used for freeing memory from PQescapeBytea()/PQunescapeBytea()
|
|
*/
|
|
void
|
|
PQfreemem(void *ptr)
|
|
{
|
|
free(ptr);
|
|
}
|
|
|
|
/*
|
|
* PQfreeNotify - free's the memory associated with a PGnotify
|
|
*
|
|
* This function is here only for binary backward compatibility.
|
|
* New code should use PQfreemem(). A macro will automatically map
|
|
* calls to PQfreemem. It should be removed in the future. bjm 2003-03-24
|
|
*/
|
|
|
|
#undef PQfreeNotify
|
|
void PQfreeNotify(PGnotify *notify);
|
|
|
|
void
|
|
PQfreeNotify(PGnotify *notify)
|
|
{
|
|
PQfreemem(notify);
|
|
}
|
|
|
|
|
|
/*
|
|
* Escaping arbitrary strings to get valid SQL literal strings.
|
|
*
|
|
* Replaces "'" with "''", and if not std_strings, replaces "\" with "\\".
|
|
*
|
|
* length is the length of the source string. (Note: if a terminating NUL
|
|
* is encountered sooner, PQescapeString stops short of "length"; the behavior
|
|
* is thus rather like strncpy.)
|
|
*
|
|
* For safety the buffer at "to" must be at least 2*length + 1 bytes long.
|
|
* A terminating NUL character is added to the output string, whether the
|
|
* input is NUL-terminated or not.
|
|
*
|
|
* Returns the actual length of the output (not counting the terminating NUL).
|
|
*/
|
|
static size_t
|
|
PQescapeStringInternal(PGconn *conn,
|
|
char *to, const char *from, size_t length,
|
|
int *error,
|
|
int encoding, bool std_strings)
|
|
{
|
|
const char *source = from;
|
|
char *target = to;
|
|
size_t remaining = length;
|
|
|
|
if (error)
|
|
*error = 0;
|
|
|
|
while (remaining > 0 && *source != '\0')
|
|
{
|
|
char c = *source;
|
|
int len;
|
|
int i;
|
|
|
|
/* Fast path for plain ASCII */
|
|
if (!IS_HIGHBIT_SET(c))
|
|
{
|
|
/* Apply quoting if needed */
|
|
if (SQL_STR_DOUBLE(c, !std_strings))
|
|
*target++ = c;
|
|
/* Copy the character */
|
|
*target++ = c;
|
|
source++;
|
|
remaining--;
|
|
continue;
|
|
}
|
|
|
|
/* Slow path for possible multibyte characters */
|
|
len = pg_encoding_mblen(encoding, source);
|
|
|
|
/* Copy the character */
|
|
for (i = 0; i < len; i++)
|
|
{
|
|
if (remaining == 0 || *source == '\0')
|
|
break;
|
|
*target++ = *source++;
|
|
remaining--;
|
|
}
|
|
|
|
/*
|
|
* If we hit premature end of string (ie, incomplete multibyte
|
|
* character), try to pad out to the correct length with spaces. We
|
|
* may not be able to pad completely, but we will always be able to
|
|
* insert at least one pad space (since we'd not have quoted a
|
|
* multibyte character). This should be enough to make a string that
|
|
* the server will error out on.
|
|
*/
|
|
if (i < len)
|
|
{
|
|
if (error)
|
|
*error = 1;
|
|
if (conn)
|
|
libpq_append_conn_error(conn, "incomplete multibyte character");
|
|
for (; i < len; i++)
|
|
{
|
|
if (((size_t) (target - to)) / 2 >= length)
|
|
break;
|
|
*target++ = ' ';
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Write the terminating NUL character. */
|
|
*target = '\0';
|
|
|
|
return target - to;
|
|
}
|
|
|
|
size_t
|
|
PQescapeStringConn(PGconn *conn,
|
|
char *to, const char *from, size_t length,
|
|
int *error)
|
|
{
|
|
if (!conn)
|
|
{
|
|
/* force empty-string result */
|
|
*to = '\0';
|
|
if (error)
|
|
*error = 1;
|
|
return 0;
|
|
}
|
|
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
return PQescapeStringInternal(conn, to, from, length, error,
|
|
conn->client_encoding,
|
|
conn->std_strings);
|
|
}
|
|
|
|
size_t
|
|
PQescapeString(char *to, const char *from, size_t length)
|
|
{
|
|
return PQescapeStringInternal(NULL, to, from, length, NULL,
|
|
static_client_encoding,
|
|
static_std_strings);
|
|
}
|
|
|
|
|
|
/*
|
|
* Escape arbitrary strings. If as_ident is true, we escape the result
|
|
* as an identifier; if false, as a literal. The result is returned in
|
|
* a newly allocated buffer. If we fail due to an encoding violation or out
|
|
* of memory condition, we return NULL, storing an error message into conn.
|
|
*/
|
|
static char *
|
|
PQescapeInternal(PGconn *conn, const char *str, size_t len, bool as_ident)
|
|
{
|
|
const char *s;
|
|
char *result;
|
|
char *rp;
|
|
int num_quotes = 0; /* single or double, depending on as_ident */
|
|
int num_backslashes = 0;
|
|
int input_len;
|
|
int result_size;
|
|
char quote_char = as_ident ? '"' : '\'';
|
|
|
|
/* We must have a connection, else fail immediately. */
|
|
if (!conn)
|
|
return NULL;
|
|
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
/* Scan the string for characters that must be escaped. */
|
|
for (s = str; (s - str) < len && *s != '\0'; ++s)
|
|
{
|
|
if (*s == quote_char)
|
|
++num_quotes;
|
|
else if (*s == '\\')
|
|
++num_backslashes;
|
|
else if (IS_HIGHBIT_SET(*s))
|
|
{
|
|
int charlen;
|
|
|
|
/* Slow path for possible multibyte characters */
|
|
charlen = pg_encoding_mblen(conn->client_encoding, s);
|
|
|
|
/* Multibyte character overruns allowable length. */
|
|
if ((s - str) + charlen > len || memchr(s, 0, charlen) != NULL)
|
|
{
|
|
libpq_append_conn_error(conn, "incomplete multibyte character");
|
|
return NULL;
|
|
}
|
|
|
|
/* Adjust s, bearing in mind that for loop will increment it. */
|
|
s += charlen - 1;
|
|
}
|
|
}
|
|
|
|
/* Allocate output buffer. */
|
|
input_len = s - str;
|
|
result_size = input_len + num_quotes + 3; /* two quotes, plus a NUL */
|
|
if (!as_ident && num_backslashes > 0)
|
|
result_size += num_backslashes + 2;
|
|
result = rp = (char *) malloc(result_size);
|
|
if (rp == NULL)
|
|
{
|
|
libpq_append_conn_error(conn, "out of memory");
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* If we are escaping a literal that contains backslashes, we use the
|
|
* escape string syntax so that the result is correct under either value
|
|
* of standard_conforming_strings. We also emit a leading space in this
|
|
* case, to guard against the possibility that the result might be
|
|
* interpolated immediately following an identifier.
|
|
*/
|
|
if (!as_ident && num_backslashes > 0)
|
|
{
|
|
*rp++ = ' ';
|
|
*rp++ = 'E';
|
|
}
|
|
|
|
/* Opening quote. */
|
|
*rp++ = quote_char;
|
|
|
|
/*
|
|
* Use fast path if possible.
|
|
*
|
|
* We've already verified that the input string is well-formed in the
|
|
* current encoding. If it contains no quotes and, in the case of
|
|
* literal-escaping, no backslashes, then we can just copy it directly to
|
|
* the output buffer, adding the necessary quotes.
|
|
*
|
|
* If not, we must rescan the input and process each character
|
|
* individually.
|
|
*/
|
|
if (num_quotes == 0 && (num_backslashes == 0 || as_ident))
|
|
{
|
|
memcpy(rp, str, input_len);
|
|
rp += input_len;
|
|
}
|
|
else
|
|
{
|
|
for (s = str; s - str < input_len; ++s)
|
|
{
|
|
if (*s == quote_char || (!as_ident && *s == '\\'))
|
|
{
|
|
*rp++ = *s;
|
|
*rp++ = *s;
|
|
}
|
|
else if (!IS_HIGHBIT_SET(*s))
|
|
*rp++ = *s;
|
|
else
|
|
{
|
|
int i = pg_encoding_mblen(conn->client_encoding, s);
|
|
|
|
while (1)
|
|
{
|
|
*rp++ = *s;
|
|
if (--i == 0)
|
|
break;
|
|
++s; /* for loop will provide the final increment */
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Closing quote and terminating NUL. */
|
|
*rp++ = quote_char;
|
|
*rp = '\0';
|
|
|
|
return result;
|
|
}
|
|
|
|
char *
|
|
PQescapeLiteral(PGconn *conn, const char *str, size_t len)
|
|
{
|
|
return PQescapeInternal(conn, str, len, false);
|
|
}
|
|
|
|
char *
|
|
PQescapeIdentifier(PGconn *conn, const char *str, size_t len)
|
|
{
|
|
return PQescapeInternal(conn, str, len, true);
|
|
}
|
|
|
|
/* HEX encoding support for bytea */
|
|
static const char hextbl[] = "0123456789abcdef";
|
|
|
|
static const int8 hexlookup[128] = {
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
|
|
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
|
};
|
|
|
|
static inline char
|
|
get_hex(char c)
|
|
{
|
|
int res = -1;
|
|
|
|
if (c > 0 && c < 127)
|
|
res = hexlookup[(unsigned char) c];
|
|
|
|
return (char) res;
|
|
}
|
|
|
|
|
|
/*
|
|
* PQescapeBytea - converts from binary string to the
|
|
* minimal encoding necessary to include the string in an SQL
|
|
* INSERT statement with a bytea type column as the target.
|
|
*
|
|
* We can use either hex or escape (traditional) encoding.
|
|
* In escape mode, the following transformations are applied:
|
|
* '\0' == ASCII 0 == \000
|
|
* '\'' == ASCII 39 == ''
|
|
* '\\' == ASCII 92 == \\
|
|
* anything < 0x20, or > 0x7e ---> \ooo
|
|
* (where ooo is an octal expression)
|
|
*
|
|
* If not std_strings, all backslashes sent to the output are doubled.
|
|
*/
|
|
static unsigned char *
|
|
PQescapeByteaInternal(PGconn *conn,
|
|
const unsigned char *from, size_t from_length,
|
|
size_t *to_length, bool std_strings, bool use_hex)
|
|
{
|
|
const unsigned char *vp;
|
|
unsigned char *rp;
|
|
unsigned char *result;
|
|
size_t i;
|
|
size_t len;
|
|
size_t bslash_len = (std_strings ? 1 : 2);
|
|
|
|
/*
|
|
* empty string has 1 char ('\0')
|
|
*/
|
|
len = 1;
|
|
|
|
if (use_hex)
|
|
{
|
|
len += bslash_len + 1 + 2 * from_length;
|
|
}
|
|
else
|
|
{
|
|
vp = from;
|
|
for (i = from_length; i > 0; i--, vp++)
|
|
{
|
|
if (*vp < 0x20 || *vp > 0x7e)
|
|
len += bslash_len + 3;
|
|
else if (*vp == '\'')
|
|
len += 2;
|
|
else if (*vp == '\\')
|
|
len += bslash_len + bslash_len;
|
|
else
|
|
len++;
|
|
}
|
|
}
|
|
|
|
*to_length = len;
|
|
rp = result = (unsigned char *) malloc(len);
|
|
if (rp == NULL)
|
|
{
|
|
if (conn)
|
|
libpq_append_conn_error(conn, "out of memory");
|
|
return NULL;
|
|
}
|
|
|
|
if (use_hex)
|
|
{
|
|
if (!std_strings)
|
|
*rp++ = '\\';
|
|
*rp++ = '\\';
|
|
*rp++ = 'x';
|
|
}
|
|
|
|
vp = from;
|
|
for (i = from_length; i > 0; i--, vp++)
|
|
{
|
|
unsigned char c = *vp;
|
|
|
|
if (use_hex)
|
|
{
|
|
*rp++ = hextbl[(c >> 4) & 0xF];
|
|
*rp++ = hextbl[c & 0xF];
|
|
}
|
|
else if (c < 0x20 || c > 0x7e)
|
|
{
|
|
if (!std_strings)
|
|
*rp++ = '\\';
|
|
*rp++ = '\\';
|
|
*rp++ = (c >> 6) + '0';
|
|
*rp++ = ((c >> 3) & 07) + '0';
|
|
*rp++ = (c & 07) + '0';
|
|
}
|
|
else if (c == '\'')
|
|
{
|
|
*rp++ = '\'';
|
|
*rp++ = '\'';
|
|
}
|
|
else if (c == '\\')
|
|
{
|
|
if (!std_strings)
|
|
{
|
|
*rp++ = '\\';
|
|
*rp++ = '\\';
|
|
}
|
|
*rp++ = '\\';
|
|
*rp++ = '\\';
|
|
}
|
|
else
|
|
*rp++ = c;
|
|
}
|
|
*rp = '\0';
|
|
|
|
return result;
|
|
}
|
|
|
|
unsigned char *
|
|
PQescapeByteaConn(PGconn *conn,
|
|
const unsigned char *from, size_t from_length,
|
|
size_t *to_length)
|
|
{
|
|
if (!conn)
|
|
return NULL;
|
|
|
|
if (conn->cmd_queue_head == NULL)
|
|
pqClearConnErrorState(conn);
|
|
|
|
return PQescapeByteaInternal(conn, from, from_length, to_length,
|
|
conn->std_strings,
|
|
(conn->sversion >= 90000));
|
|
}
|
|
|
|
unsigned char *
|
|
PQescapeBytea(const unsigned char *from, size_t from_length, size_t *to_length)
|
|
{
|
|
return PQescapeByteaInternal(NULL, from, from_length, to_length,
|
|
static_std_strings,
|
|
false /* can't use hex */ );
|
|
}
|
|
|
|
|
|
#define ISFIRSTOCTDIGIT(CH) ((CH) >= '0' && (CH) <= '3')
|
|
#define ISOCTDIGIT(CH) ((CH) >= '0' && (CH) <= '7')
|
|
#define OCTVAL(CH) ((CH) - '0')
|
|
|
|
/*
|
|
* PQunescapeBytea - converts the null terminated string representation
|
|
* of a bytea, strtext, into binary, filling a buffer. It returns a
|
|
* pointer to the buffer (or NULL on error), and the size of the
|
|
* buffer in retbuflen. The pointer may subsequently be used as an
|
|
* argument to the function PQfreemem.
|
|
*
|
|
* The following transformations are made:
|
|
* \\ == ASCII 92 == \
|
|
* \ooo == a byte whose value = ooo (ooo is an octal number)
|
|
* \x == x (x is any character not matched by the above transformations)
|
|
*/
|
|
unsigned char *
|
|
PQunescapeBytea(const unsigned char *strtext, size_t *retbuflen)
|
|
{
|
|
size_t strtextlen,
|
|
buflen;
|
|
unsigned char *buffer,
|
|
*tmpbuf;
|
|
size_t i,
|
|
j;
|
|
|
|
if (strtext == NULL)
|
|
return NULL;
|
|
|
|
strtextlen = strlen((const char *) strtext);
|
|
|
|
if (strtext[0] == '\\' && strtext[1] == 'x')
|
|
{
|
|
const unsigned char *s;
|
|
unsigned char *p;
|
|
|
|
buflen = (strtextlen - 2) / 2;
|
|
/* Avoid unportable malloc(0) */
|
|
buffer = (unsigned char *) malloc(buflen > 0 ? buflen : 1);
|
|
if (buffer == NULL)
|
|
return NULL;
|
|
|
|
s = strtext + 2;
|
|
p = buffer;
|
|
while (*s)
|
|
{
|
|
char v1,
|
|
v2;
|
|
|
|
/*
|
|
* Bad input is silently ignored. Note that this includes
|
|
* whitespace between hex pairs, which is allowed by byteain.
|
|
*/
|
|
v1 = get_hex(*s++);
|
|
if (!*s || v1 == (char) -1)
|
|
continue;
|
|
v2 = get_hex(*s++);
|
|
if (v2 != (char) -1)
|
|
*p++ = (v1 << 4) | v2;
|
|
}
|
|
|
|
buflen = p - buffer;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Length of input is max length of output, but add one to avoid
|
|
* unportable malloc(0) if input is zero-length.
|
|
*/
|
|
buffer = (unsigned char *) malloc(strtextlen + 1);
|
|
if (buffer == NULL)
|
|
return NULL;
|
|
|
|
for (i = j = 0; i < strtextlen;)
|
|
{
|
|
switch (strtext[i])
|
|
{
|
|
case '\\':
|
|
i++;
|
|
if (strtext[i] == '\\')
|
|
buffer[j++] = strtext[i++];
|
|
else
|
|
{
|
|
if ((ISFIRSTOCTDIGIT(strtext[i])) &&
|
|
(ISOCTDIGIT(strtext[i + 1])) &&
|
|
(ISOCTDIGIT(strtext[i + 2])))
|
|
{
|
|
int byte;
|
|
|
|
byte = OCTVAL(strtext[i++]);
|
|
byte = (byte << 3) + OCTVAL(strtext[i++]);
|
|
byte = (byte << 3) + OCTVAL(strtext[i++]);
|
|
buffer[j++] = byte;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note: if we see '\' followed by something that isn't a
|
|
* recognized escape sequence, we loop around having done
|
|
* nothing except advance i. Therefore the something will
|
|
* be emitted as ordinary data on the next cycle. Corner
|
|
* case: '\' at end of string will just be discarded.
|
|
*/
|
|
break;
|
|
|
|
default:
|
|
buffer[j++] = strtext[i++];
|
|
break;
|
|
}
|
|
}
|
|
buflen = j; /* buflen is the length of the dequoted data */
|
|
}
|
|
|
|
/* Shrink the buffer to be no larger than necessary */
|
|
/* +1 avoids unportable behavior when buflen==0 */
|
|
tmpbuf = realloc(buffer, buflen + 1);
|
|
|
|
/* It would only be a very brain-dead realloc that could fail, but... */
|
|
if (!tmpbuf)
|
|
{
|
|
free(buffer);
|
|
return NULL;
|
|
}
|
|
|
|
*retbuflen = buflen;
|
|
return tmpbuf;
|
|
}
|