コード例 #1
0
ファイル: fe-protocol2.c プロジェクト: 0x0FFF/postgres
/*
 * Attempt to read an Error or Notice response message.
 * This is possible in several places, so we break it out as a subroutine.
 * Entry: 'E' or 'N' message type has already been consumed.
 * Exit: returns 0 if successfully consumed message.
 *		 returns EOF if not enough data.
 */
static int
pqGetErrorNotice2(PGconn *conn, bool isError)
{
	PGresult   *res = NULL;
	PQExpBufferData workBuf;
	char	   *startp;
	char	   *splitp;

	/*
	 * Since the message might be pretty long, we create a temporary
	 * PQExpBuffer rather than using conn->workBuffer.  workBuffer is intended
	 * for stuff that is expected to be short.
	 */
	initPQExpBuffer(&workBuf);
	if (pqGets(&workBuf, conn))
		goto failure;

	/*
	 * Make a PGresult to hold the message.  We temporarily lie about the
	 * result status, so that PQmakeEmptyPGresult doesn't uselessly copy
	 * conn->errorMessage.
	 *
	 * NB: This allocation can fail, if you run out of memory. The rest of the
	 * function handles that gracefully, and we still try to set the error
	 * message as the connection's error message.
	 */
	res = PQmakeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
	if (res)
	{
		res->resultStatus = isError ? PGRES_FATAL_ERROR : PGRES_NONFATAL_ERROR;
		res->errMsg = pqResultStrdup(res, workBuf.data);
	}

	/*
	 * Break the message into fields.  We can't do very much here, but we can
	 * split the severity code off, and remove trailing newlines. Also, we use
	 * the heuristic that the primary message extends only to the first
	 * newline --- anything after that is detail message.  (In some cases it'd
	 * be better classed as hint, but we can hardly be expected to guess that
	 * here.)
	 */
	while (workBuf.len > 0 && workBuf.data[workBuf.len - 1] == '\n')
		workBuf.data[--workBuf.len] = '\0';
	splitp = strstr(workBuf.data, ":  ");
	if (splitp)
	{
		/* what comes before the colon is severity */
		*splitp = '\0';
		pqSaveMessageField(res, PG_DIAG_SEVERITY, workBuf.data);
		startp = splitp + 3;
	}
	else
	{
		/* can't find a colon?  oh well... */
		startp = workBuf.data;
	}
	splitp = strchr(startp, '\n');
	if (splitp)
	{
		/* what comes before the newline is primary message */
		*splitp++ = '\0';
		pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, startp);
		/* the rest is detail; strip any leading whitespace */
		while (*splitp && isspace((unsigned char) *splitp))
			splitp++;
		pqSaveMessageField(res, PG_DIAG_MESSAGE_DETAIL, splitp);
	}
	else
	{
		/* single-line message, so all primary */
		pqSaveMessageField(res, PG_DIAG_MESSAGE_PRIMARY, startp);
	}

	/*
	 * Either save error as current async result, or just emit the notice.
	 * Also, if it's an error and we were in a transaction block, assume the
	 * server has now gone to error-in-transaction state.
	 */
	if (isError)
	{
		pqClearAsyncResult(conn);
		conn->result = res;
		resetPQExpBuffer(&conn->errorMessage);
		if (res && !PQExpBufferDataBroken(workBuf) && res->errMsg)
			appendPQExpBufferStr(&conn->errorMessage, res->errMsg);
		else
			printfPQExpBuffer(&conn->errorMessage,
							  libpq_gettext("out of memory"));
		if (conn->xactStatus == PQTRANS_INTRANS)
			conn->xactStatus = PQTRANS_INERROR;
	}
	else
	{
		if (res)
		{
			if (res->noticeHooks.noticeRec != NULL)
				(*res->noticeHooks.noticeRec) (res->noticeHooks.noticeRecArg, res);
			PQclear(res);
		}
	}

	termPQExpBuffer(&workBuf);
	return 0;

failure:
	if (res)
		PQclear(res);
	termPQExpBuffer(&workBuf);
	return EOF;
}
コード例 #2
0
ファイル: fe-protocol2.c プロジェクト: 0x0FFF/postgres
/*
 * parseInput subroutine to read a 'T' (row descriptions) message.
 * We build a PGresult structure containing the attribute data.
 * Returns: 0 if completed message, EOF if error or not enough data
 * received yet.
 *
 * Note that if we run out of data, we have to suspend and reprocess
 * the message after more data is received.  Otherwise, conn->inStart
 * must get advanced past the processed data.
 */
static int
getRowDescriptions(PGconn *conn)
{
	PGresult   *result;
	int			nfields;
	const char *errmsg;
	int			i;

	result = PQmakeEmptyPGresult(conn, PGRES_TUPLES_OK);
	if (!result)
	{
		errmsg = NULL;			/* means "out of memory", see below */
		goto advance_and_error;
	}

	/* parseInput already read the 'T' label. */
	/* the next two bytes are the number of fields	*/
	if (pqGetInt(&(result->numAttributes), 2, conn))
		goto EOFexit;
	nfields = result->numAttributes;

	/* allocate space for the attribute descriptors */
	if (nfields > 0)
	{
		result->attDescs = (PGresAttDesc *)
			pqResultAlloc(result, nfields * sizeof(PGresAttDesc), TRUE);
		if (!result->attDescs)
		{
			errmsg = NULL;		/* means "out of memory", see below */
			goto advance_and_error;
		}
		MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
	}

	/* get type info */
	for (i = 0; i < nfields; i++)
	{
		int			typid;
		int			typlen;
		int			atttypmod;

		if (pqGets(&conn->workBuffer, conn) ||
			pqGetInt(&typid, 4, conn) ||
			pqGetInt(&typlen, 2, conn) ||
			pqGetInt(&atttypmod, 4, conn))
			goto EOFexit;

		/*
		 * Since pqGetInt treats 2-byte integers as unsigned, we need to
		 * coerce the result to signed form.
		 */
		typlen = (int) ((int16) typlen);

		result->attDescs[i].name = pqResultStrdup(result,
												  conn->workBuffer.data);
		if (!result->attDescs[i].name)
		{
			errmsg = NULL;		/* means "out of memory", see below */
			goto advance_and_error;
		}
		result->attDescs[i].tableid = 0;
		result->attDescs[i].columnid = 0;
		result->attDescs[i].format = 0;
		result->attDescs[i].typid = typid;
		result->attDescs[i].typlen = typlen;
		result->attDescs[i].atttypmod = atttypmod;
	}

	/* Success! */
	conn->result = result;

	/* Advance inStart to show that the "T" message has been processed. */
	conn->inStart = conn->inCursor;

	/*
	 * We could perform additional setup for the new result set here, but for
	 * now there's nothing else to do.
	 */

	/* And we're done. */
	return 0;

advance_and_error:

	/*
	 * Discard the failed message.  Unfortunately we don't know for sure where
	 * the end is, so just throw away everything in the input buffer. This is
	 * not very desirable but it's the best we can do in protocol v2.
	 */
	conn->inStart = conn->inEnd;

	/*
	 * Replace partially constructed result with an error result. First
	 * discard the old result to try to win back some memory.
	 */
	pqClearAsyncResult(conn);

	/*
	 * If preceding code didn't provide an error message, assume "out of
	 * memory" was meant.  The advantage of having this special case is that
	 * freeing the old result first greatly improves the odds that gettext()
	 * will succeed in providing a translation.
	 */
	if (!errmsg)
		errmsg = libpq_gettext("out of memory for query result");

	printfPQExpBuffer(&conn->errorMessage, "%s\n", errmsg);

	/*
	 * XXX: if PQmakeEmptyPGresult() fails, there's probably not much we can
	 * do to recover...
	 */
	conn->result = PQmakeEmptyPGresult(conn, PGRES_FATAL_ERROR);
	conn->asyncStatus = PGASYNC_READY;

EOFexit:
	if (result && result != conn->result)
		PQclear(result);
	return EOF;
}
コード例 #3
0
/*
 * parseInput subroutine to read a 'T' (row descriptions) message.
 * We'll build a new PGresult structure (unless called for a Describe
 * command for a prepared statement) containing the attribute data.
 * Returns: 0 if completed message, EOF if not enough data yet.
 *
 * Note that if we run out of data, we have to release the partially
 * constructed PGresult, and rebuild it again next time.  Fortunately,
 * that shouldn't happen often, since 'T' messages usually fit in a packet.
 */
static int
getRowDescriptions(PGconn *conn)
{
	PGresult   *result;
	int			nfields;
	int			i;

	/*
	 * When doing Describe for a prepared statement, there'll already be a
	 * PGresult created by getParamDescriptions, and we should fill data into
	 * that.  Otherwise, create a new, empty PGresult.
	 */
	if (conn->queryclass == PGQUERY_DESCRIBE)
	{
		if (conn->result)
			result = conn->result;
		else
			result = PQmakeEmptyPGresult(conn, PGRES_COMMAND_OK);
	}
	else
		result = PQmakeEmptyPGresult(conn, PGRES_TUPLES_OK);
	if (!result)
		goto failure;

	/* parseInput already read the 'T' label and message length. */
	/* the next two bytes are the number of fields */
	if (pqGetInt(&(result->numAttributes), 2, conn))
		goto failure;
	nfields = result->numAttributes;

	/* allocate space for the attribute descriptors */
	if (nfields > 0)
	{
		result->attDescs = (PGresAttDesc *)
			pqResultAlloc(result, nfields * sizeof(PGresAttDesc), TRUE);
		if (!result->attDescs)
			goto failure;
		MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
	}

	/* result->binary is true only if ALL columns are binary */
	result->binary = (nfields > 0) ? 1 : 0;

	/* get type info */
	for (i = 0; i < nfields; i++)
	{
		int			tableid;
		int			columnid;
		int			typid;
		int			typlen;
		int			atttypmod;
		int			format;

		if (pqGets(&conn->workBuffer, conn) ||
			pqGetInt(&tableid, 4, conn) ||
			pqGetInt(&columnid, 2, conn) ||
			pqGetInt(&typid, 4, conn) ||
			pqGetInt(&typlen, 2, conn) ||
			pqGetInt(&atttypmod, 4, conn) ||
			pqGetInt(&format, 2, conn))
		{
			goto failure;
		}

		/*
		 * Since pqGetInt treats 2-byte integers as unsigned, we need to
		 * coerce these results to signed form.
		 */
		columnid = (int) ((int16) columnid);
		typlen = (int) ((int16) typlen);
		format = (int) ((int16) format);

		result->attDescs[i].name = pqResultStrdup(result,
												  conn->workBuffer.data);
		if (!result->attDescs[i].name)
			goto failure;
		result->attDescs[i].tableid = tableid;
		result->attDescs[i].columnid = columnid;
		result->attDescs[i].format = format;
		result->attDescs[i].typid = typid;
		result->attDescs[i].typlen = typlen;
		result->attDescs[i].atttypmod = atttypmod;

		if (format != 1)
			result->binary = 0;
	}

	/* Success! */
	conn->result = result;
	return 0;

failure:

	/*
	 * Discard incomplete result, unless it's from getParamDescriptions.
	 *
	 * Note that if we hit a bufferload boundary while handling the
	 * describe-statement case, we'll forget any PGresult space we just
	 * allocated, and then reallocate it on next try.  This will bloat the
	 * PGresult a little bit but the space will be freed at PQclear, so it
	 * doesn't seem worth trying to be smarter.
	 */
	if (result != conn->result)
		PQclear(result);
	return EOF;
}
コード例 #4
0
/*
 * Attempt to read an Error or Notice response message.
 * This is possible in several places, so we break it out as a subroutine.
 * Entry: 'E' or 'N' message type and length have already been consumed.
 * Exit: returns 0 if successfully consumed message.
 *		 returns EOF if not enough data.
 */
int
pqGetErrorNotice3(PGconn *conn, bool isError)
{
	PGresult   *res = NULL;
	PQExpBufferData workBuf;
	char		id;
	const char *val;
	const char *querytext = NULL;
	int			querypos = 0;

	/*
	 * Since the fields might be pretty long, we create a temporary
	 * PQExpBuffer rather than using conn->workBuffer.	workBuffer is intended
	 * for stuff that is expected to be short.	We shouldn't use
	 * conn->errorMessage either, since this might be only a notice.
	 */
	initPQExpBuffer(&workBuf);

	/*
	 * Make a PGresult to hold the accumulated fields.	We temporarily lie
	 * about the result status, so that PQmakeEmptyPGresult doesn't uselessly
	 * copy conn->errorMessage.
	 */
	res = PQmakeEmptyPGresult(conn, PGRES_EMPTY_QUERY);
	if (!res)
		goto fail;
	res->resultStatus = isError ? PGRES_FATAL_ERROR : PGRES_NONFATAL_ERROR;

	/*
	 * Read the fields and save into res.
	 */
	for (;;)
	{
		if (pqGetc(&id, conn))
			goto fail;
		if (id == '\0')
			break;				/* terminator found */
		if (pqGets(&workBuf, conn))
			goto fail;
		pqSaveMessageField(res, id, workBuf.data);
	}

	/*
	 * Now build the "overall" error message for PQresultErrorMessage.
	 */
	resetPQExpBuffer(&workBuf);
	val = PQresultErrorField(res, PG_DIAG_SEVERITY);
	if (val)
		appendPQExpBuffer(&workBuf, "%s:  ", val);
	if (conn->verbosity == PQERRORS_VERBOSE)
	{
		val = PQresultErrorField(res, PG_DIAG_SQLSTATE);
		if (val)
			appendPQExpBuffer(&workBuf, "%s: ", val);
	}
	val = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
	if (val)
		appendPQExpBufferStr(&workBuf, val);
	val = PQresultErrorField(res, PG_DIAG_STATEMENT_POSITION);
	if (val)
	{
		if (conn->verbosity != PQERRORS_TERSE && conn->last_query != NULL)
		{
			/* emit position as a syntax cursor display */
			querytext = conn->last_query;
			querypos = atoi(val);
		}
		else
		{
			/* emit position as text addition to primary message */
			/* translator: %s represents a digit string */
			appendPQExpBuffer(&workBuf, libpq_gettext(" at character %s"),
							  val);
		}
	}
	else
	{
		val = PQresultErrorField(res, PG_DIAG_INTERNAL_POSITION);
		if (val)
		{
			querytext = PQresultErrorField(res, PG_DIAG_INTERNAL_QUERY);
			if (conn->verbosity != PQERRORS_TERSE && querytext != NULL)
			{
				/* emit position as a syntax cursor display */
				querypos = atoi(val);
			}
			else
			{
				/* emit position as text addition to primary message */
				/* translator: %s represents a digit string */
				appendPQExpBuffer(&workBuf, libpq_gettext(" at character %s"),
								  val);
			}
		}
	}
	appendPQExpBufferChar(&workBuf, '\n');
	if (conn->verbosity != PQERRORS_TERSE)
	{
		if (querytext && querypos > 0)
			reportErrorPosition(&workBuf, querytext, querypos,
								conn->client_encoding);
		val = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
		if (val)
			appendPQExpBuffer(&workBuf, libpq_gettext("DETAIL:  %s\n"), val);
		val = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
		if (val)
			appendPQExpBuffer(&workBuf, libpq_gettext("HINT:  %s\n"), val);
		val = PQresultErrorField(res, PG_DIAG_INTERNAL_QUERY);
		if (val)
			appendPQExpBuffer(&workBuf, libpq_gettext("QUERY:  %s\n"), val);
		val = PQresultErrorField(res, PG_DIAG_CONTEXT);
		if (val)
			appendPQExpBuffer(&workBuf, libpq_gettext("CONTEXT:  %s\n"), val);
	}
	if (conn->verbosity == PQERRORS_VERBOSE)
	{
		const char *valf;
		const char *vall;

		valf = PQresultErrorField(res, PG_DIAG_SOURCE_FILE);
		vall = PQresultErrorField(res, PG_DIAG_SOURCE_LINE);
		val = PQresultErrorField(res, PG_DIAG_SOURCE_FUNCTION);
		if (val || valf || vall)
		{
			appendPQExpBufferStr(&workBuf, libpq_gettext("LOCATION:  "));
			if (val)
				appendPQExpBuffer(&workBuf, libpq_gettext("%s, "), val);
			if (valf && vall)	/* unlikely we'd have just one */
				appendPQExpBuffer(&workBuf, libpq_gettext("%s:%s"),
								  valf, vall);
			appendPQExpBufferChar(&workBuf, '\n');
		}
	}

	/*
	 * Either save error as current async result, or just emit the notice.
	 */
	if (isError)
	{
		res->errMsg = pqResultStrdup(res, workBuf.data);
		if (!res->errMsg)
			goto fail;
		pqClearAsyncResult(conn);
		conn->result = res;
		resetPQExpBuffer(&conn->errorMessage);
		appendPQExpBufferStr(&conn->errorMessage, workBuf.data);
	}
	else
	{
		/* We can cheat a little here and not copy the message. */
		res->errMsg = workBuf.data;
		if (res->noticeHooks.noticeRec != NULL)
			(*res->noticeHooks.noticeRec) (res->noticeHooks.noticeRecArg, res);
		PQclear(res);
	}

	termPQExpBuffer(&workBuf);
	return 0;

fail:
	PQclear(res);
	termPQExpBuffer(&workBuf);
	return EOF;
}
コード例 #5
0
/*
 * parseInput subroutine to read a 'T' (row descriptions) message.
 * We build a PGresult structure containing the attribute data.
 * Returns: 0 if completed message, EOF if not enough data yet.
 *
 * Note that if we run out of data, we have to release the partially
 * constructed PGresult, and rebuild it again next time.  Fortunately,
 * that shouldn't happen often, since 'T' messages usually fit in a packet.
 */
static int
getRowDescriptions(PGconn *conn)
{
	PGresult   *result = NULL;
	int			nfields;
	int			i;

	result = PQmakeEmptyPGresult(conn, PGRES_TUPLES_OK);
	if (!result)
		goto failure;

	/* parseInput already read the 'T' label. */
	/* the next two bytes are the number of fields	*/
	if (pqGetInt(&(result->numAttributes), 2, conn))
		goto failure;
	nfields = result->numAttributes;

	/* allocate space for the attribute descriptors */
	if (nfields > 0)
	{
		result->attDescs = (PGresAttDesc *)
			pqResultAlloc(result, nfields * sizeof(PGresAttDesc), TRUE);
		if (!result->attDescs)
			goto failure;
		MemSet(result->attDescs, 0, nfields * sizeof(PGresAttDesc));
	}

	/* get type info */
	for (i = 0; i < nfields; i++)
	{
		int			typid;
		int			typlen;
		int			atttypmod;

		if (pqGets(&conn->workBuffer, conn) ||
			pqGetInt(&typid, 4, conn) ||
			pqGetInt(&typlen, 2, conn) ||
			pqGetInt(&atttypmod, 4, conn))
			goto failure;

		/*
		 * Since pqGetInt treats 2-byte integers as unsigned, we need to
		 * coerce the result to signed form.
		 */
		typlen = (int) ((int16) typlen);

		result->attDescs[i].name = pqResultStrdup(result,
												  conn->workBuffer.data);
		if (!result->attDescs[i].name)
			goto failure;
		result->attDescs[i].tableid = 0;
		result->attDescs[i].columnid = 0;
		result->attDescs[i].format = 0;
		result->attDescs[i].typid = typid;
		result->attDescs[i].typlen = typlen;
		result->attDescs[i].atttypmod = atttypmod;
	}

	/* Success! */
	conn->result = result;
	return 0;

failure:
	if (result)
		PQclear(result);
	return EOF;
}