From bf9f00f16b9825c5df235c2df4b325f97fed199a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?John=20H=C3=B6gberg?= <john@erlang.org>
Date: Fri, 29 Sep 2017 14:51:09 +0200
Subject: Fix minor incompatibilities in inflate behavior

When presented with multiple valid but concatenated streams, the
old driver returned an empty result once the end of the first
stream was reached, and kept doing so even if fed new data. The
new driver/NIF returned a data_error instead.

zlib:inflateInit/3 has been added to control this behavior, but is
not yet ready for public use.
---
 erts/preloaded/src/zlib.erl | 34 ++++++++++++++++++++++++----------
 1 file changed, 24 insertions(+), 10 deletions(-)

(limited to 'erts/preloaded/src/zlib.erl')

diff --git a/erts/preloaded/src/zlib.erl b/erts/preloaded/src/zlib.erl
index dca5a42779..7bd9234a90 100644
--- a/erts/preloaded/src/zlib.erl
+++ b/erts/preloaded/src/zlib.erl
@@ -23,7 +23,7 @@
 -export([open/0,close/1,deflateInit/1,deflateInit/2,deflateInit/6,
          deflateSetDictionary/2,deflateReset/1,deflateParams/3,
          deflate/2,deflate/3,deflateEnd/1,
-         inflateInit/1,inflateInit/2,
+         inflateInit/1,inflateInit/2,inflateInit/3,
          inflateSetDictionary/2,inflateGetDictionary/1, inflateReset/1,
          inflate/2,inflate/3,inflateEnd/1,
          inflateChunk/2,inflateChunk/1,
@@ -68,6 +68,13 @@
 
 -define(MAX_WBITS, 15).
 
+-define(DEFAULT_MEMLEVEL, 8).
+-define(DEFAULT_WBITS, 15).
+
+-define(EOS_BEHAVIOR_ERROR, 0).
+-define(EOS_BEHAVIOR_RESET, 1).
+-define(EOS_BEHAVIOR_CUT, 2).
+
 %% Chunk sizes are hardcoded on account of them screwing with the
 %% predictability of the system. zlib is incapable of trapping so we need to
 %% ensure that it never operates on any significant amount of data.
@@ -130,10 +137,7 @@ deflateInit(Z) ->
       Z :: zstream(),
       Level :: zlevel().
 deflateInit(Z, Level) ->
-    deflateInit_nif(Z, arg_level(Level)).
-
-deflateInit_nif(_Z, _Level) ->
-    erlang:nif_error(undef).
+    deflateInit(Z, Level, deflated, ?DEFAULT_WBITS, ?DEFAULT_MEMLEVEL, default).
 
 -spec deflateInit(Z, Level, Method, WindowBits, MemLevel, Strategy) -> 'ok' when
       Z :: zstream(),
@@ -225,16 +229,21 @@ deflateEnd_nif(_Z) ->
 -spec inflateInit(Z) -> 'ok' when
       Z :: zstream().
 inflateInit(Z) ->
-    inflateInit_nif(Z).
-inflateInit_nif(_Z) ->
-    erlang:nif_error(undef).
+    inflateInit(Z, ?DEFAULT_WBITS).
 
 -spec inflateInit(Z, WindowBits) -> 'ok' when
       Z :: zstream(),
       WindowBits :: zwindowbits().
 inflateInit(Z, WindowBits) ->
-    inflateInit_nif(Z, WindowBits).
-inflateInit_nif(_Z, _WindowBits) ->
+    inflateInit(Z, WindowBits, cut).
+
+-spec inflateInit(Z, WindowBits, EoSBehavior) -> 'ok' when
+      Z :: zstream(),
+      WindowBits :: zwindowbits(),
+      EoSBehavior :: error | reset | cut.
+inflateInit(Z, WindowBits, EoSBehavior) ->
+    inflateInit_nif(Z, arg_bitsz(WindowBits), arg_eos_behavior(EoSBehavior)).
+inflateInit_nif(_Z, _WindowBits, _EoSBehavior) ->
     erlang:nif_error(undef).
 
 -spec inflateSetDictionary(Z, Dictionary) -> 'ok' when
@@ -652,6 +661,11 @@ arg_strategy(_) -> erlang:error(bad_compression_strategy).
 arg_method(deflated) -> ?Z_DEFLATED;
 arg_method(_) -> erlang:error(bad_compression_method).
 
+arg_eos_behavior(error) -> ?EOS_BEHAVIOR_ERROR;
+arg_eos_behavior(reset) -> ?EOS_BEHAVIOR_RESET;
+arg_eos_behavior(cut) -> ?EOS_BEHAVIOR_CUT;
+arg_eos_behavior(_) -> erlang:error(bad_eos_behavior).
+
 -spec arg_bitsz(zwindowbits()) -> zwindowbits().
 arg_bitsz(Bits) when is_integer(Bits) andalso
                      ((8 =< Bits andalso Bits < 48) orelse
-- 
cgit v1.2.3