From bf0f197f566b688df0e0c6a5a343019643732d86 Mon Sep 17 00:00:00 2001 From: Raimo Niskanen Date: Wed, 3 Jul 2019 11:47:57 +0200 Subject: Refine the queue code --- lib/ssl/src/ssl_connection.erl | 13 ++++++++++++- lib/ssl/src/tls_record.erl | 18 +++++++++++++----- 2 files changed, 25 insertions(+), 6 deletions(-) diff --git a/lib/ssl/src/ssl_connection.erl b/lib/ssl/src/ssl_connection.erl index af9f0cbf3a..b3b1dc18dc 100644 --- a/lib/ssl/src/ssl_connection.erl +++ b/lib/ssl/src/ssl_connection.erl @@ -673,7 +673,18 @@ read_application_dist_data(DHandle, Front0, BufferSize, Rear0, Bin0) -> iovec_from_front(0, Front, Rear, Acc) -> {lists:reverse(Acc),Front,Rear}; iovec_from_front(Size, [], Rear, Acc) -> - iovec_from_front(Size, lists:reverse(Rear), [], Acc); + case Rear of + %% Avoid lists:reverse/1 for simple cases. + %% Case clause for [] to avoid infinite loop. + [_] -> + iovec_from_front(Size, Rear, [], Acc); + [Bin2,Bin1] -> + iovec_from_front(Size, [Bin1,Bin2], [], Acc); + [Bin3,Bin2,Bin1] -> + iovec_from_front(Size, [Bin1,Bin2,Bin3], [], Acc); + [_,_,_|_] = Rear -> + iovec_from_front(Size, lists:reverse(Rear), [], Acc) + end; iovec_from_front(Size, [Bin|Front], Rear, Acc) -> case Bin of <> -> % Just enough diff --git a/lib/ssl/src/tls_record.erl b/lib/ssl/src/tls_record.erl index afbf95948d..20598ea702 100644 --- a/lib/ssl/src/tls_record.erl +++ b/lib/ssl/src/tls_record.erl @@ -495,11 +495,19 @@ binary_from_front(SplitSize, {Front,Size,Rear}) when SplitSize =< Size -> binary_from_front(SplitSize, Front, Size, Rear, []). %% %% SplitSize > 0 and there is at least SplitSize bytes buffered in Front and Rear -binary_from_front(SplitSize, [], Size, [_] = Rear, Acc) -> - %% Optimize a simple case - avoid lists:reverse/1 - binary_from_front(SplitSize, Rear, Size, [], Acc); -binary_from_front(SplitSize, [], Size, [_|_] = Rear, Acc) -> - binary_from_front(SplitSize, lists:reverse(Rear), Size, [], Acc); +binary_from_front(SplitSize, [], Size, Rear, Acc) -> + case Rear of + %% Avoid lists:reverse/1 for simple cases. + %% Case clause for [] to avoid infinite loop. + [_] -> + binary_from_front(SplitSize, Rear, Size, [], Acc); + [Bin2,Bin1] -> + binary_from_front(SplitSize, [Bin1,Bin2], Size, [], Acc); + [Bin3,Bin2,Bin1] -> + binary_from_front(SplitSize, [Bin1,Bin2,Bin3], Size, [], Acc); + [_,_,_|_] -> + binary_from_front(SplitSize, lists:reverse(Rear), Size, [], Acc) + end; binary_from_front(SplitSize, [Bin|Front], Size, Rear, []) -> %% Optimize the frequent case when the accumulator is empty BinSize = byte_size(Bin), -- cgit v1.2.3