From 70066eb1a1adb4d1ac608c1127bbb3139fa09942 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 17 Jan 2008 21:21:50 +0000 Subject: [PATCH] Insert into getCopyDataMessage() the same logic that already existed in the main code path for enlarging libpq's input buffer in one swoop when needing to read a long data message. Without this, the code will double the buffer size, read more data, notice it still hasn't got the whole message, and repeat till it finally has a large enough buffer. Which wastes a lot of data-moving effort and also memory (since malloc probably can't do anything very useful with the freed-up smaller buffers). Not sure why this wasn't there already; certainly the COPY data path is a place where we're quite likely to see long data messages. I'm not backpatching though, since this is just a marginal performance issue rather than a real bug. --- src/interfaces/libpq/fe-protocol3.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c index c40868805f..89c0d5018f 100644 --- a/src/interfaces/libpq/fe-protocol3.c +++ b/src/interfaces/libpq/fe-protocol3.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/interfaces/libpq/fe-protocol3.c,v 1.33 2008/01/15 22:18:20 tgl Exp $ + * $PostgreSQL: pgsql/src/interfaces/libpq/fe-protocol3.c,v 1.34 2008/01/17 21:21:50 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1305,7 +1305,24 @@ getCopyDataMessage(PGconn *conn) } avail = conn->inEnd - conn->inCursor; if (avail < msgLength - 4) + { + /* + * Before returning, enlarge the input buffer if needed to hold + * the whole message. See notes in parseInput. + */ + if (pqCheckInBufferSpace(conn->inCursor + msgLength - 4, conn)) + { + /* + * XXX add some better recovery code... plan is to skip over + * the message using its length, then report an error. For the + * moment, just treat this like loss of sync (which indeed it + * might be!) + */ + handleSyncLoss(conn, id, msgLength); + return -2; + } return 0; + } /* * If it's a legitimate async message type, process it. (NOTIFY -- 2.40.0