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-rw-r--r--erts/doc/src/erl_nif.xml251
-rw-r--r--erts/doc/src/erlang.xml17
-rw-r--r--erts/doc/src/zlib.xml227
3 files changed, 445 insertions, 50 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index 50e07f019e..419e41693e 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -344,6 +344,81 @@ return term;</code>
<c>enif_convert_time_unit()</c></seealso></item>
</list>
</item>
+ <tag><marker id="enif_ioq"/>I/O Queues</tag>
+ <item>
+ <p>The Erlang nif library contains function for easily working
+ with I/O vectors as used by the unix system call <c>writev</c>.
+ The I/O Queue is not thread safe, so some other synchronization
+ mechanism has to be used.</p>
+ <list type="bulleted">
+ <item><seealso marker="#SysIOVec">
+ <c>SysIOVec</c></seealso></item>
+ <item><seealso marker="#ErlNifIOVec">
+ <c>ErlNifIOVec</c></seealso></item>
+ <item><seealso marker="#enif_ioq_create">
+ <c>enif_ioq_create()</c></seealso></item>
+ <item><seealso marker="#enif_ioq_destroy">
+ <c>enif_ioq_destroy()</c></seealso></item>
+ <item><seealso marker="#enif_ioq_enq_binary">
+ <c>enif_ioq_enq_binary()</c></seealso></item>
+ <item><seealso marker="#enif_ioq_enqv">
+ <c>enif_ioq_enqv()</c></seealso></item>
+ <item><seealso marker="#enif_ioq_deq">
+ <c>enif_ioq_deq()</c></seealso></item>
+ <item><seealso marker="#enif_ioq_peek">
+ <c>enif_ioq_peek()</c></seealso></item>
+ <item><seealso marker="#enif_inspect_iovec">
+ <c>enif_inspect_iovec()</c></seealso></item>
+ <item><seealso marker="#enif_free_iovec">
+ <c>enif_free_iovec()</c></seealso></item>
+ </list>
+ <p>Typical usage when writing to a file descriptor looks like this:</p>
+ <code type="none"><![CDATA[
+int writeiovec(ErlNifEnv *env, ERL_NIF_TERM term, ERL_NIF_TERM *tail,
+ ErlNifIOQueue *q, int fd) {
+
+ ErlNifIOVec vec, *iovec = &vec;
+ SysIOVec *sysiovec;
+ int saved_errno;
+ int iovcnt, n;
+
+ if (!enif_inspect_iovec(env, 64, term, tail, &iovec))
+ return -2;
+
+ if (enif_ioq_size(q) > 0) {
+ /* If the I/O queue contains data we enqueue the iovec and
+ then peek the data to write out of the queue. */
+ if (!enif_ioq_enqv(q, iovec, 0))
+ return -3;
+
+ sysiovec = enif_ioq_peek(q, &iovcnt);
+ } else {
+ /* If the I/O queue is empty we skip the trip through it. */
+ iovcnt = iovec->iovcnt;
+ sysiovec = iovec->iov;
+ }
+
+ /* Attempt to write the data */
+ n = writev(fd, sysiovec, iovcnt);
+ saved_errno = errno;
+
+ if (enif_ioq_size(q) == 0) {
+ /* If the I/O queue was initially empty we enqueue any
+ remaining data into the queue for writing later. */
+ if (n >= 0 && !enif_ioq_enqv(q, iovec, n))
+ return -3;
+ } else {
+ /* Dequeue any data that was written from the queue. */
+ if (n > 0 && !enif_ioq_deq(q, n, NULL))
+ return -4;
+ }
+
+ /* return n, which is either number of bytes written or -1 if
+ some error happened */
+ errno = saved_errno;
+ return n;
+}]]></code>
+ </item>
<tag><marker id="lengthy_work"/>Long-running NIFs</tag>
<item>
<p>As mentioned in the <seealso marker="#WARNING">warning</seealso> text
@@ -837,6 +912,36 @@ typedef enum {
</item>
</taglist>
</item>
+ <tag><marker id="SysIOVec"/><c>SysIOVec</c></tag>
+ <item>
+ <p>A system I/O vector, as used by <c>writev</c> on
+ Unix and <c>WSASend</c> on Win32. It is used in
+ <c>ErlNifIOVec</c> and by
+ <seealso marker="#enif_ioq_peek"><c>enif_ioq_peek</c></seealso>.</p>
+ </item>
+ <tag><marker id="ErlNifIOVec"/><c>ErlNifIOVec</c></tag>
+ <item>
+ <code type="none">
+typedef struct {
+ int iovcnt;
+ size_t size;
+ SysIOVec* iov;
+} ErlNifIOVec;</code>
+ <p>An I/O vector containing <c>iovcnt</c> <c>SysIOVec</c>s
+ pointing to the data. It is used by
+ <seealso marker="#enif_inspect_iovec">
+ <c>enif_inspect_iovec</c></seealso> and
+ <seealso marker="#enif_ioq_enqv">
+ <c>enif_ioq_enqv</c></seealso>.</p>
+ </item>
+ <tag><marker id="ErlNifIOQueueOpts"/><c>ErlNifIOQueueOpts</c></tag>
+ <item>
+ Options to configure a <c>ErlNifIOQueue</c>.
+ <taglist>
+ <tag>ERL_NIF_IOQ_NORMAL</tag>
+ <item><p>Create a normal I/O Queue</p></item>
+ </taglist>
+ </item>
</taglist>
</section>
@@ -1143,6 +1248,31 @@ typedef enum {
</func>
<func>
+ <name><ret>void</ret>
+ <nametext>enif_free_iovec(ErlNifIOvec* iov)</nametext></name>
+ <fsummary>Free an ErlIOVec</fsummary>
+ <desc>
+ <p>Frees an io vector returned from
+ <seealso marker="#enif_inspect_iovec">
+ <c>enif_inspect_iovec</c></seealso>.
+ This is needed only if a <c>NULL</c> environment is passed to
+ <seealso marker="#enif_inspect_iovec">
+ <c>enif_inspect_iovec</c></seealso>.</p>
+ <code type="none"><![CDATA[
+ErlNifIOVec *iovec = NULL;
+size_t max_elements = 128;
+ERL_NIF_TERM tail;
+if (!enif_inspect_iovec(NULL, max_elements, term, &tail, iovec))
+ return 0;
+
+// Do things with the iovec
+
+/* Free the iovector, possibly in another thread or nif function call */
+enif_free_iovec(iovec);]]></code>
+ </desc>
+ </func>
+
+ <func>
<name><ret>int</ret><nametext>enif_get_atom(ErlNifEnv* env, ERL_NIF_TERM
term, char* buf, unsigned size, ErlNifCharEncoding encode)</nametext>
</name>
@@ -1449,6 +1579,127 @@ typedef enum {
</func>
<func>
+ <name><ret>int</ret><nametext>enif_inspect_iovec(ErlNifEnv*
+ env, size_t max_elements, ERL_NIF_TERM iovec_term, ERL_NIF_TERM* tail,
+ ErlNifIOVec** iovec)</nametext></name>
+ <fsummary>Inspect a list of binaries as an ErlNifIOVec.</fsummary>
+ <desc>
+ <p>Fills <c>iovec</c> with the list of binaries provided in
+ <c>iovec_term</c>. The number of elements handled in the call is
+ limited to <c>max_elements</c>, and <c>tail</c> is set to the
+ remainder of the list. Note that the output may be longer than
+ <c>max_elements</c> on some platforms.
+ </p>
+ <p>To create a list of binaries from an arbitrary iolist, use
+ <seealso marker="erts:erlang#iolist_to_iovec/1">
+ <c>erlang:iolist_to_iovec/1</c></seealso>.</p>
+ <p>When calling this function, <c>iovec</c> should contain a pointer to
+ <c>NULL</c> or a ErlNifIOVec structure that should be used if
+ possible. e.g.
+ </p>
+ <code type="none">
+/* Don't use a pre-allocated structure */
+ErlNifIOVec *iovec = NULL;
+enif_inspect_iovec(env, max_elements, term, &amp;tail, &amp;iovec);
+
+/* Use a stack-allocated vector as an optimization for vectors with few elements */
+ErlNifIOVec vec, *iovec = &amp;vec;
+enif_inspect_iovec(env, max_elements, term, &amp;tail, &amp;iovec);
+</code>
+ <p>The contents of the <c>iovec</c> is valid until the called nif
+ function returns. If the <c>iovec</c> should be valid after the nif
+ call returns, it is possible to call this function with a
+ <c>NULL</c> environment. If no environment is given the <c>iovec</c>
+ owns the data in the vector and it has to be explicitly freed using
+ <seealso marker="#enif_free_iovec"><c>enif_free_iovec</c>
+ </seealso>.</p>
+ <p>Returns <c>true</c> on success, or <c>false</c> if <c>iovec_term</c>
+ not an iovec.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>ErlNifIOQueue *</ret>
+ <nametext>enif_ioq_create(ErlNifIOQueueOpts opts)</nametext></name>
+ <fsummary>Create a new IO Queue</fsummary>
+ <desc>
+ <p>Create a new I/O Queue that can be used to store data.
+ <c>opts</c> has to be set to <c>ERL_NIF_IOQ_NORMAL</c>.
+ </p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>void</ret>
+ <nametext>enif_ioq_destroy(ErlNifIOQueue *q)</nametext></name>
+ <fsummary>Destroy an IO Queue and free it's content</fsummary>
+ <desc>
+ <p>Destroy the I/O queue and free all of it's contents</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>int</ret>
+ <nametext>enif_ioq_deq(ErlNifIOQueue *q, size_t count, size_t *size)</nametext></name>
+ <fsummary>Dequeue count bytes from the IO Queue</fsummary>
+ <desc>
+ <p>Dequeue <c>count</c> bytes from the I/O queue.
+ If <c>size</c> is not <c>NULL</c>, the new size of the queue
+ is placed there.</p>
+ <p>Returns <c>true</c> on success, or <c>false</c> if the I/O does
+ not contain <c>count</c> bytes. On failure the queue is left un-altered.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>int</ret>
+ <nametext>enif_ioq_enq_binary(ErlNifIOQueue *q, ErlNifBinary *bin, size_t skip)</nametext></name>
+ <fsummary>Enqueue the binary into the IO Queue</fsummary>
+ <desc>
+ <p>Enqueue the <c>bin</c> into <c>q</c> skipping the first <c>skip</c> bytes.</p>
+ <p>Returns <c>true</c> on success, or <c>false</c> if <c>skip</c> is greater
+ than the size of <c>bin</c>. Any ownership of the binary data is transferred
+ to the queue and <c>bin</c> is to be considered read-only for the rest of the NIF
+ call and then as released.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>int</ret>
+ <nametext>enif_ioq_enqv(ErlNifIOQueue *q, ErlNifIOVec *iovec, size_t skip)</nametext></name>
+ <fsummary>Enqueue the iovec into the IO Queue</fsummary>
+ <desc>
+ <p>Enqueue the <c>iovec</c> into <c>q</c> skipping the first <c>skip</c> bytes.</p>
+ <p>Returns <c>true</c> on success, or <c>false</c> if <c>skip</c> is greater
+ than the size of <c>iovec</c>.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>SysIOVec *</ret>
+ <nametext>enif_ioq_peek(ErlNifIOQueue *q, int *iovlen)</nametext></name>
+ <fsummary>Peek inside the IO Queue</fsummary>
+ <desc>
+ <p>Get the I/O queue as a pointer to an array of <c>SysIOVec</c>s.
+ It also returns the number of elements in <c>iovlen</c>.
+ This is the only way to get data out of the queue.</p>
+ <p>Nothing is removed from the queue by this function, that must be done
+ with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p>
+ <p>The returned array is suitable to use with the Unix system
+ call <c>writev</c>.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name><ret>size_t</ret>
+ <nametext>enif_ioq_size(ErlNifIOQueue *q)</nametext></name>
+ <fsummary>Get the current size of the IO Queue</fsummary>
+ <desc>
+ <p>Get the size of <c>q</c>.</p>
+ </desc>
+ </func>
+
+ <func>
<name><ret>int</ret>
<nametext>enif_is_atom(ErlNifEnv* env, ERL_NIF_TERM term)</nametext>
</name>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 11f2d36a01..5afac46d21 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -60,6 +60,14 @@
</desc>
</datatype>
<datatype>
+ <name>iovec()</name>
+ <desc>
+ <p>A list of binaries. This datatype is useful to use
+ together with <seealso marker="erl_nif#enif_inspect_iovec">
+ <c>enif_inspect_iovec</c></seealso>.</p>
+ </desc>
+ </datatype>
+ <datatype>
<name name="message_queue_data"></name>
<desc>
<p>See <seealso marker="#process_flag_message_queue_data">
@@ -2128,6 +2136,15 @@ os_prompt%</pre>
</func>
<func>
+ <name name="iolist_to_iovec" arity="1"/>
+ <fsummary>Converts an iolist to a iovec.</fsummary>
+ <desc>
+ <p>Returns an iovec that is made from the integers and binaries in
+ <c><anno>IoListOrBinary</anno></c>.</p>
+ </desc>
+ </func>
+
+ <func>
<name name="is_alive" arity="0"/>
<fsummary>Check whether the local node is alive.</fsummary>
<desc>
diff --git a/erts/doc/src/zlib.xml b/erts/doc/src/zlib.xml
index 1d272c4c18..f5cc1b1e64 100644
--- a/erts/doc/src/zlib.xml
+++ b/erts/doc/src/zlib.xml
@@ -65,13 +65,17 @@ list_to_binary([Compressed|Last])</pre>
<tag><c>badarg</c></tag>
<item>Bad argument.
</item>
+ <tag><c>not_initialized</c></tag>
+ <item>The stream hasn't been initialized, eg. if
+ <seealso marker="#inflateInit/1"><c>inflateInit/1</c></seealso> wasn't
+ called prior to a call to
+ <seealso marker="#inflate/2"><c>inflate/2</c></seealso>.
+ </item>
<tag><c>data_error</c></tag>
<item>The data contains errors.
</item>
<tag><c>stream_error</c></tag>
<item>Inconsistent stream state.</item>
- <tag><c>einval</c></tag>
- <item>Bad value or wrong function called.</item>
<tag><c>{need_dictionary,Adler32}</c></tag>
<item>See <seealso marker="#inflate/2"><c>inflate/2</c></seealso>.
</item>
@@ -90,6 +94,9 @@ list_to_binary([Compressed|Last])</pre>
<name name="zlevel"/>
</datatype>
<datatype>
+ <name name="zflush"/>
+ </datatype>
+ <datatype>
<name name="zmemlevel"/>
</datatype>
<datatype>
@@ -112,6 +119,11 @@ list_to_binary([Compressed|Last])</pre>
<fsummary>Calculate the Adler checksum.</fsummary>
<desc>
<p>Calculates the Adler-32 checksum for <c><anno>Data</anno></c>.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#adler32/1">
+ <c>erlang:adler32/1</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -127,6 +139,11 @@ list_to_binary([Compressed|Last])</pre>
Crc = lists:foldl(fun(Data,Crc0) ->
zlib:adler32(Z, Crc0, Data),
end, zlib:adler32(Z,&lt;&lt; &gt;&gt;), Datas)</pre>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#adler32/2">
+ <c>erlang:adler32/2</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -141,6 +158,11 @@ Crc = lists:foldl(fun(Data,Crc0) ->
<p>This function returns the <c><anno>Adler</anno></c> checksum of
<c>[Data1,Data2]</c>, requiring only <c><anno>Adler1</anno></c>,
<c><anno>Adler2</anno></c>, and <c><anno>Size2</anno></c>.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#adler32_combine/3">
+ <c>erlang:adler32_combine/3</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -165,6 +187,12 @@ Crc = lists:foldl(fun(Data,Crc0) ->
<fsummary>Get current CRC.</fsummary>
<desc>
<p>Gets the current calculated CRC checksum.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#crc32/1">
+ <c>erlang:crc32/1</c></seealso> on the uncompressed data
+ instead.</p>
+ </warning>
</desc>
</func>
@@ -173,6 +201,11 @@ Crc = lists:foldl(fun(Data,Crc0) ->
<fsummary>Calculate CRC.</fsummary>
<desc>
<p>Calculates the CRC checksum for <c><anno>Data</anno></c>.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#crc32/1">
+ <c>erlang:crc32/1</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -188,6 +221,11 @@ Crc = lists:foldl(fun(Data,Crc0) ->
Crc = lists:foldl(fun(Data,Crc0) ->
zlib:crc32(Z, Crc0, Data),
end, zlib:crc32(Z,&lt;&lt; &gt;&gt;), Datas)</pre>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#crc32/2">
+ <c>erlang:crc32/2</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -202,6 +240,11 @@ Crc = lists:foldl(fun(Data,Crc0) ->
<p>This function returns the <c><anno>CRC</anno></c> checksum of
<c>[Data1,Data2]</c>, requiring only <c><anno>CRC1</anno></c>,
<c><anno>CRC2</anno></c>, and <c><anno>Size2</anno></c>.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="erts:erlang#crc32_combine/3">
+ <c>erlang:crc32_combine/3</c></seealso> instead.</p>
+ </warning>
</desc>
</func>
@@ -407,8 +450,8 @@ list_to_binary([B1,B2])</pre>
<seealso marker="#deflateInit/1"><c>deflateInit/1,2,6</c></seealso> or
<seealso marker="#deflateReset/1"><c>deflateReset/1</c></seealso>,
before any call of
- <seealso marker="#deflate/3"><c>deflate/3</c></seealso>.
- The compressor and decompressor must use the same dictionary (see
+ <seealso marker="#deflate/3"><c>deflate/3</c></seealso>.</p>
+ <p>The compressor and decompressor must use the same dictionary (see
<seealso marker="#inflateSetDictionary/2">
<c>inflateSetDictionary/2</c></seealso>).</p>
<p>The Adler checksum of the dictionary is returned.</p>
@@ -420,6 +463,10 @@ list_to_binary([B1,B2])</pre>
<fsummary>Get buffer size.</fsummary>
<desc>
<p>Gets the size of the intermediate buffer.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release.</p>
+ </warning>
</desc>
</func>
@@ -443,14 +490,31 @@ list_to_binary([B1,B2])</pre>
<name name="inflate" arity="2"/>
<fsummary>Decompress data.</fsummary>
<desc>
- <p>Decompresses as much data as possible.
- It can introduce some output latency (reading
- input without producing any output).</p>
- <p>If a preset dictionary is needed at this point (see
- <seealso marker="#inflateSetDictionary/2">
- <c>inflateSetDictionary/2</c></seealso>), <c>inflate/2</c> throws a
- <c>{need_dictionary,Adler}</c> exception, where <c>Adler</c> is
- the Adler-32 checksum of the dictionary chosen by the compressor.</p>
+ <p>Equivalent to
+ <seealso marker="#inflate/3"><c>inflate(Z, Data, [])</c></seealso>
+ </p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="inflate" arity="3"/>
+ <fsummary>Decompress data.</fsummary>
+ <desc>
+ <p>Decompresses as much data as possible. It can introduce some output
+ latency (reading input without producing any output).</p>
+ <p>Currently the only available option is
+ <c>{exception_on_need_dict,boolean()}</c> which controls whether the
+ function should throw an exception when a preset dictionary is
+ required for decompression. When set to false, a
+ <c>need_dictionary</c> tuple will be returned instead. See
+ <seealso marker="#inflateSetDictionary/2">
+ <c>inflateSetDictionary/2</c></seealso> for details.</p>
+ <warning>
+ <p>This option defaults to <c>true</c> for backwards compatibility
+ but we intend to remove the exception behavior in a future
+ release. New code that needs to handle dictionaries manually
+ should always specify <c>{exception_on_need_dict,false}</c>.</p>
+ </warning>
</desc>
</func>
@@ -458,6 +522,11 @@ list_to_binary([B1,B2])</pre>
<name name="inflateChunk" arity="1"/>
<fsummary>Read next uncompressed chunk.</fsummary>
<desc>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="#safeInflate/2"><c>safeInflate/2</c>
+ </seealso> instead.</p>
+ </warning>
<p>Reads the next chunk of uncompressed data, initialized by
<seealso marker="#inflateChunk/2"><c>inflateChunk/2</c></seealso>.</p>
<p>This function is to be repeatedly called, while it returns
@@ -469,23 +538,27 @@ list_to_binary([B1,B2])</pre>
<name name="inflateChunk" arity="2"/>
<fsummary>Decompress data with limited output size.</fsummary>
<desc>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release. Use <seealso marker="#safeInflate/2"><c>safeInflate/2</c>
+ </seealso> instead.</p>
+ </warning>
<p>Like <seealso marker="#inflate/2"><c>inflate/2</c></seealso>,
- but decompresses no more data than will fit in the buffer configured
- through <seealso marker="#setBufSize/2"><c>setBufSize/2</c></seealso>.
- Is is useful when decompressing a stream with a high compression
- ratio, such that a small amount of compressed input can expand up to
- 1000 times.</p>
+ but decompresses no more data than will fit in the buffer configured
+ through <seealso marker="#setBufSize/2"><c>setBufSize/2</c>
+ </seealso>. Is is useful when decompressing a stream with a high
+ compression ratio, such that a small amount of compressed input can
+ expand up to 1000 times.</p>
<p>This function returns <c>{more, Decompressed}</c>, when there is
- more output available, and
- <seealso marker="#inflateChunk/1"><c>inflateChunk/1</c></seealso>
- is to be used to read it.</p>
- <p>This function can introduce some output latency (reading
- input without producing any output).</p>
- <p>If a preset dictionary is needed at this point (see
- <seealso marker="#inflateSetDictionary/2">
- <c>inflateSetDictionary/2</c></seealso>), this function throws a
- <c>{need_dictionary,Adler}</c> exception, where <c>Adler</c> is
- the Adler-32 checksum of the dictionary chosen by the compressor.</p>
+ more output available, and
+ <seealso marker="#inflateChunk/1"><c>inflateChunk/1</c></seealso>
+ is to be used to read it.</p>
+ <p>This function can introduce some output latency (reading input
+ without producing any output).</p>
+ <p>An exception will be thrown if a preset dictionary is required for
+ further decompression. See
+ <seealso marker="#inflateSetDictionary/2">
+ <c>inflateSetDictionary/2</c></seealso> for details.</p>
<p>Example:</p>
<pre>
walk(Compressed, Handler) ->
@@ -517,6 +590,18 @@ loop(Z, Handler, Uncompressed) ->
</func>
<func>
+ <name name="inflateGetDictionary" arity="1"/>
+ <fsummary>Return the decompression dictionary.</fsummary>
+ <desc>
+ <p>Returns the decompression dictionary currently in use
+ by the stream. This function must be called between
+ <seealso marker="#inflateInit/1"><c>inflateInit/1,2</c></seealso>
+ and <seealso marker="#inflateEnd/1"><c>inflateEnd</c></seealso>.</p>
+ <p>Only supported if ERTS was compiled with zlib >= 1.2.8.</p>
+ </desc>
+ </func>
+
+ <func>
<name name="inflateInit" arity="1"/>
<fsummary>Initialize a session for decompression.</fsummary>
<desc>
@@ -562,45 +647,83 @@ loop(Z, Handler, Uncompressed) ->
<fsummary>Initialize the decompression dictionary.</fsummary>
<desc>
<p>Initializes the decompression dictionary from the specified
- uncompressed byte sequence. This function must be called
- immediately after a call of
- <seealso marker="#inflate/2"><c>inflate/2</c></seealso>
- if this call threw a <c>{need_dictionary,Adler}</c> exception.
- The dictionary chosen by the compressor can be determined from the
- Adler value thrown by the call to <c>inflate/2</c>.
- The compressor and decompressor must use the same dictionary (see
- <seealso marker="#deflateSetDictionary/2">
- <c>deflateSetDictionary/2</c></seealso>).</p>
+ uncompressed byte sequence. This function must be called as a
+ response to an inflate operation (eg.
+ <seealso marker="#safeInflate/2"><c>safeInflate/2</c></seealso>)
+ returning <c>{need_dictionary,Adler,Output}</c> or in the case of
+ deprecated functions, throwing an
+ <c>{'EXIT',{{need_dictionary,Adler},_StackTrace}}</c> exception.</p>
+ <p>The dictionary chosen by the compressor can be determined from the
+ Adler value returned or thrown by the call to the inflate function.
+ The compressor and decompressor must use the same dictionary (See
+ <seealso marker="#deflateSetDictionary/2">
+ <c>deflateSetDictionary/2</c></seealso>).</p>
+ <p>After setting the dictionary the inflate operation should be
+ retried without new input.</p>
<p>Example:</p>
<pre>
-unpack(Z, Compressed, Dict) ->
+deprecated_unpack(Z, Compressed, Dict) ->
case catch zlib:inflate(Z, Compressed) of
- {'EXIT',{{need_dictionary,DictID},_}} ->
- zlib:inflateSetDictionary(Z, Dict),
+ {'EXIT',{{need_dictionary,_DictID},_}} ->
+ ok = zlib:inflateSetDictionary(Z, Dict),
Uncompressed = zlib:inflate(Z, []);
Uncompressed ->
Uncompressed
- end.</pre>
+ end.
+
+new_unpack(Z, Compressed, Dict) ->
+ case zlib:inflate(Z, Compressed, [{exception_on_need_dict, false}]) of
+ {need_dictionary, _DictId, Output} ->
+ ok = zlib:inflateSetDictionary(Z, Dict),
+ [Output | zlib:inflate(Z, [])];
+ Uncompressed ->
+ Uncompressed
+ end.</pre>
</desc>
</func>
<func>
- <name name="inflateGetDictionary" arity="1"/>
- <fsummary>Return the decompression dictionary.</fsummary>
+ <name name="open" arity="0"/>
+ <fsummary>Open a stream and return a stream reference.</fsummary>
<desc>
- <p>Returns the decompression dictionary currently in use
- by the stream. This function must be called between
- <seealso marker="#inflateInit/1"><c>inflateInit/1,2</c></seealso>
- and <seealso marker="#inflateEnd/1"><c>inflateEnd</c></seealso>.</p>
- <p>Only supported if ERTS was compiled with zlib >= 1.2.8.</p>
+ <p>Opens a zlib stream.</p>
</desc>
</func>
<func>
- <name name="open" arity="0"/>
- <fsummary>Open a stream and return a stream reference.</fsummary>
+ <name name="safeInflate" arity="2"/>
+ <fsummary>Decompress data with limited output size.</fsummary>
<desc>
- <p>Opens a zlib stream.</p>
+ <p>Like <seealso marker="#inflate/2"><c>inflate/2</c></seealso>,
+ but returns once it has expanded beyond a small
+ implementation-defined threshold. It's useful when decompressing
+ untrusted input which could have been maliciously crafted to expand
+ until the system runs out of memory.</p>
+ <p>This function returns <c>{continue | finished, Output}</c>, where
+ <anno>Output</anno> is the data that was decompressed in this call.
+ New input can be queued up on each call if desired, and the function
+ will return <c>{finished, Output}</c> once all queued data has been
+ decompressed.</p>
+ <p>This function can introduce some output latency (reading
+ input without producing any output).</p>
+ <p>If a preset dictionary is required for further decompression, this
+ function returns a <c>need_dictionary</c> tuple. See
+ <seealso marker="#inflateSetDictionary/2">
+ <c>inflateSetDictionary/2</c></seealso>) for details.</p>
+ <p>Example:</p>
+ <pre>
+walk(Compressed, Handler) ->
+ Z = zlib:open(),
+ zlib:inflateInit(Z),
+ loop(Z, Handler, zlib:safeInflate(Z, Compressed)),
+ zlib:inflateEnd(Z),
+ zlib:close(Z).
+
+loop(Z, Handler, {continue, Output}) ->
+ Handler(Output),
+ loop(Z, Handler, zlib:safeInflate(Z, []));
+loop(Z, Handler, {finished, Output}) ->
+ Handler(Output).</pre>
</desc>
</func>
@@ -609,6 +732,10 @@ unpack(Z, Compressed, Dict) ->
<fsummary>Set buffer size.</fsummary>
<desc>
<p>Sets the intermediate buffer size.</p>
+ <warning>
+ <p>This function is deprecated and will be removed in a future
+ release.</p>
+ </warning>
</desc>
</func>