diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/interfaces/libpq/fe-misc.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/src/interfaces/libpq/fe-misc.c b/src/interfaces/libpq/fe-misc.c index a28a09790b6..7a213bf8390 100644 --- a/src/interfaces/libpq/fe-misc.c +++ b/src/interfaces/libpq/fe-misc.c @@ -351,6 +351,7 @@ pqCheckOutBufferSpace(size_t bytes_needed, PGconn *conn) int newsize = conn->outBufSize; char *newbuf; + /* Quick exit if we have enough space */ if (bytes_needed <= (size_t) newsize) return 0; @@ -414,6 +415,37 @@ pqCheckInBufferSpace(size_t bytes_needed, PGconn *conn) int newsize = conn->inBufSize; char *newbuf; + /* Quick exit if we have enough space */ + if (bytes_needed <= (size_t) newsize) + return 0; + + /* + * Before concluding that we need to enlarge the buffer, left-justify + * whatever is in it and recheck. The caller's value of bytes_needed + * includes any data to the left of inStart, but we can delete that in + * preference to enlarging the buffer. It's slightly ugly to have this + * function do this, but it's better than making callers worry about it. + */ + bytes_needed -= conn->inStart; + + if (conn->inStart < conn->inEnd) + { + if (conn->inStart > 0) + { + memmove(conn->inBuffer, conn->inBuffer + conn->inStart, + conn->inEnd - conn->inStart); + conn->inEnd -= conn->inStart; + conn->inCursor -= conn->inStart; + conn->inStart = 0; + } + } + else + { + /* buffer is logically empty, reset it */ + conn->inStart = conn->inCursor = conn->inEnd = 0; + } + + /* Recheck whether we have enough space */ if (bytes_needed <= (size_t) newsize) return 0; |