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-rw-r--r--erts/doc/src/zlib.xml53
1 files changed, 50 insertions, 3 deletions
diff --git a/erts/doc/src/zlib.xml b/erts/doc/src/zlib.xml
index da8ccdecdf..1f10ddef6d 100644
--- a/erts/doc/src/zlib.xml
+++ b/erts/doc/src/zlib.xml
@@ -99,7 +99,7 @@ list_to_binary([Compressed|Last])</pre>
<datatype>
<name name="zwindowbits"/>
<desc>
- <p>Normally in the range <c>-15..-9 | 9..15</c>.</p>
+ <p>Normally in the range <c>-15..-8 | 8..15</c>.</p>
</desc>
</datatype>
</datatypes>
@@ -149,7 +149,7 @@ list_to_binary([Compressed|Last])</pre>
currently the only supported method is <c>deflated</c>.</p>
<p>The <c><anno>WindowBits</anno></c> parameter is the base two logarithm
of the window size (the size of the history buffer). It
- should be in the range 9 through 15. Larger values
+ should be in the range 8 through 15. Larger values
of this parameter result in better compression at the
expense of memory usage. The default value is 15 if
<c>deflateInit/2</c>. A negative <c><anno>WindowBits</anno></c>
@@ -288,7 +288,7 @@ list_to_binary([B1,B2])</pre>
<p>Initialize decompression session on zlib stream.</p>
<p>The <c><anno>WindowBits</anno></c> parameter is the base two logarithm
of the maximum window size (the size of the history buffer).
- It should be in the range 9 through 15.
+ It should be in the range 8 through 15.
The default value is 15 if <c>inflateInit/1</c> is used.
If a compressed stream with a larger window size is
given as input, inflate() will throw the <c>data_error</c>
@@ -312,6 +312,53 @@ list_to_binary([B1,B2])</pre>
</desc>
</func>
<func>
+ <name name="inflateChunk" arity="2"/>
+ <fsummary>Decompress data with limited output size</fsummary>
+ <desc>
+ <p>Like <c>inflate/2</c>, but decompress no more data than
+ will fit in the buffer configured via <c>setBufSize/2</c>.
+ Is is useful when decompressing a stream with a high compression
+ ratio such that a small amount of compressed input may expand up to
+ 1000 times.
+ It returns <c>{more, Decompressed}</c>, when there is more output
+ available, and <c>inflateChunk/1</c> should be used to read it.
+ It may introduce some output latency (reading
+ input without producing any output).</p>
+ <p>If a preset dictionary is needed at this point (see
+ <c>inflateSetDictionary</c> below), <c>inflateChunk/2</c> throws a
+ <c>{need_dictionary,Adler}</c> exception where <c>Adler</c> is
+ the adler32 checksum of the dictionary chosen by the
+ compressor.</p>
+
+ <pre>
+walk(Compressed, Handler) ->
+ Z = zlib:open(),
+ zlib:inflateInit(Z),
+ % Limit single uncompressed chunk size to 512kb
+ zlib:setBufSize(Z, 512 * 1024),
+ loop(Z, Handler, zlib:inflateChunk(Z, Compressed)),
+ zlib:inflateEnd(Z),
+ zlib:close(Z).
+
+loop(Z, Handler, {more, Uncompressed}) ->
+ Handler(Uncompressed),
+ loop(Z, Handler, zlib:inflateChunk(Z));
+loop(Z, Handler, Uncompressed) ->
+ Handler(Uncompressed).
+ </pre>
+ </desc>
+ </func>
+ <func>
+ <name name="inflateChunk" arity="1"/>
+ <fsummary>Read next uncompressed chunk</fsummary>
+ <desc>
+ <p>Read next chunk of uncompressed data, initialized by
+ <c>inflateChunk/2</c>.</p>
+ <p>This function should be repeatedly called, while it returns
+ <c>{more, Decompressed}</c>.</p>
+ </desc>
+ </func>
+ <func>
<name name="inflateSetDictionary" arity="2"/>
<fsummary>Initialize the decompression dictionary</fsummary>
<desc>