Minor edits to the documentation in source file contents.
This commit is contained in:
Mark Adler
parent
9674807c82
commit
001300d0d9
2
zconf.h
2
zconf.h
@ -251,7 +251,7 @@
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Of course this will generally degrade compression (there's no free lunch).
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The memory requirements for inflate are (in bytes) 1 << windowBits
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that is, 32K for windowBits=15 (default value) plus a few kilobytes
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that is, 32K for windowBits=15 (default value) plus about 7 kilobytes
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for small objects.
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*/
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@ -253,7 +253,7 @@
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Of course this will generally degrade compression (there's no free lunch).
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The memory requirements for inflate are (in bytes) 1 << windowBits
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that is, 32K for windowBits=15 (default value) plus a few kilobytes
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that is, 32K for windowBits=15 (default value) plus about 7 kilobytes
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for small objects.
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*/
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@ -251,7 +251,7 @@
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Of course this will generally degrade compression (there's no free lunch).
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The memory requirements for inflate are (in bytes) 1 << windowBits
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that is, 32K for windowBits=15 (default value) plus a few kilobytes
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that is, 32K for windowBits=15 (default value) plus about 7 kilobytes
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for small objects.
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*/
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192
zlib.h
192
zlib.h
@ -65,7 +65,8 @@ extern "C" {
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with "gz". The gzip format is different from the zlib format. gzip is a
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gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
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This library can optionally read and write gzip streams in memory as well.
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This library can optionally read and write gzip and raw deflate streams in
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memory as well.
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The zlib format was designed to be compact and fast for use in memory
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and on communications channels. The gzip format was designed for single-
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@ -74,7 +75,7 @@ extern "C" {
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The library does not install any signal handler. The decoder checks
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the consistency of the compressed data, so the library should never crash
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even in case of corrupted input.
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even in the case of corrupted input.
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*/
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typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
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@ -87,7 +88,7 @@ typedef struct z_stream_s {
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uInt avail_in; /* number of bytes available at next_in */
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uLong total_in; /* total number of input bytes read so far */
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Bytef *next_out; /* next output byte should be put there */
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Bytef *next_out; /* next output byte will go here */
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uInt avail_out; /* remaining free space at next_out */
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uLong total_out; /* total number of bytes output so far */
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@ -98,8 +99,9 @@ typedef struct z_stream_s {
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free_func zfree; /* used to free the internal state */
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voidpf opaque; /* private data object passed to zalloc and zfree */
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int data_type; /* best guess about the data type: binary or text */
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uLong adler; /* adler32 value of the uncompressed data */
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int data_type; /* best guess about the data type: binary or text
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for deflate, or the decoding state for inflate */
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uLong adler; /* Adler-32 or CRC-32 value of the uncompressed data */
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uLong reserved; /* reserved for future use */
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} z_stream;
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@ -142,7 +144,9 @@ typedef gz_header FAR *gz_headerp;
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zalloc must return Z_NULL if there is not enough memory for the object.
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If zlib is used in a multi-threaded application, zalloc and zfree must be
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thread safe.
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thread safe. In that case, zlib is thread-safe. When zalloc and zfree are
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Z_NULL on entry to the initialization function, they are set to internal
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routines that use the standard library functions malloc() and free().
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On 16-bit systems, the functions zalloc and zfree must be able to allocate
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exactly 65536 bytes, but will not be required to allocate more than this if
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@ -155,7 +159,7 @@ typedef gz_header FAR *gz_headerp;
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The fields total_in and total_out can be used for statistics or progress
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reports. After compression, total_in holds the total size of the
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uncompressed data and may be saved for use in the decompressor (particularly
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uncompressed data and may be saved for use by the decompressor (particularly
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if the decompressor wants to decompress everything in a single step).
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*/
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@ -200,7 +204,7 @@ typedef gz_header FAR *gz_headerp;
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#define Z_TEXT 1
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#define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */
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#define Z_UNKNOWN 2
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/* Possible values of the data_type field (though see inflate()) */
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/* Possible values of the data_type field for deflate() */
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#define Z_DEFLATED 8
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/* The deflate compression method (the only one supported in this version) */
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@ -258,11 +262,11 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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enough room in the output buffer), next_in and avail_in are updated and
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processing will resume at this point for the next call of deflate().
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- Provide more output starting at next_out and update next_out and avail_out
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- Generate more output starting at next_out and update next_out and avail_out
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accordingly. This action is forced if the parameter flush is non zero.
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Forcing flush frequently degrades the compression ratio, so this parameter
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should be set only when necessary (in interactive applications). Some
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output may be provided even if flush is not set.
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should be set only when necessary. Some output may be provided even if
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flush is zero.
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Before the call of deflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming more
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@ -271,7 +275,9 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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output when it wants, for example when the output buffer is full (avail_out
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== 0), or after each call of deflate(). If deflate returns Z_OK and with
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zero avail_out, it must be called again after making room in the output
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buffer because there might be more output pending.
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buffer because there might be more output pending. See deflatePending(),
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which can be used if desired to determine whether or not there is more ouput
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in that case.
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Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
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decide how much data to accumulate before producing output, in order to
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@ -292,8 +298,8 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
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This completes the current deflate block and follows it with an empty fixed
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codes block that is 10 bits long. This assures that enough bytes are output
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in order for the decompressor to finish the block before the empty fixed code
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block.
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in order for the decompressor to finish the block before the empty fixed
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codes block.
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If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
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for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
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@ -319,34 +325,38 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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If the parameter flush is set to Z_FINISH, pending input is processed,
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pending output is flushed and deflate returns with Z_STREAM_END if there was
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enough output space; if deflate returns with Z_OK, this function must be
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called again with Z_FINISH and more output space (updated avail_out) but no
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more input data, until it returns with Z_STREAM_END or an error. After
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deflate has returned Z_STREAM_END, the only possible operations on the stream
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are deflateReset or deflateEnd.
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enough output space. If deflate returns with Z_OK or Z_BUF_ERROR, this
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function must be called again with Z_FINISH and more output space (updated
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avail_out) but no more input data, until it returns with Z_STREAM_END or an
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error. After deflate has returned Z_STREAM_END, the only possible operations
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on the stream are deflateReset or deflateEnd.
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Z_FINISH can be used immediately after deflateInit if all the compression
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is to be done in a single step. In this case, avail_out must be at least the
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value returned by deflateBound (see below). Then deflate is guaranteed to
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return Z_STREAM_END. If not enough output space is provided, deflate will
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not return Z_STREAM_END, and it must be called again as described above.
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Z_FINISH can be used in the first deflate call after deflateInit if all the
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compression is to be done in a single step. In order to complete in one
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call, avail_out must be at least the value returned by deflateBound (see
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below). Then deflate is guaranteed to return Z_STREAM_END. If not enough
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output space is provided, deflate will not return Z_STREAM_END, and it must
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be called again as described above.
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deflate() sets strm->adler to the adler32 checksum of all input read
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so far (that is, total_in bytes).
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deflate() sets strm->adler to the Adler-32 checksum of all input read
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so far (that is, total_in bytes). If a gzip stream is being generated, then
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strm->adler will be the CRC-32 checksum of the input read so far. (See
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deflateInit2 below.)
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deflate() may update strm->data_type if it can make a good guess about
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the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
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binary. This field is only for information purposes and does not affect the
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compression algorithm in any manner.
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the input data type (Z_BINARY or Z_TEXT). If in doubt, the data is
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considered binary. This field is only for information purposes and does not
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affect the compression algorithm in any manner.
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deflate() returns Z_OK if some progress has been made (more input
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processed or more output produced), Z_STREAM_END if all input has been
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consumed and all output has been produced (only when flush is set to
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Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
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if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible
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(for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
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fatal, and deflate() can be called again with more input and more output
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space to continue compressing.
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if next_in or next_out was Z_NULL or the state was inadvertently written over
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by the application), or Z_BUF_ERROR if no progress is possible (for example
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avail_in or avail_out was zero). Note that Z_BUF_ERROR is not fatal, and
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deflate() can be called again with more input and more output space to
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continue compressing.
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*/
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@ -369,23 +379,20 @@ ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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Initializes the internal stream state for decompression. The fields
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next_in, avail_in, zalloc, zfree and opaque must be initialized before by
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the caller. If next_in is not Z_NULL and avail_in is large enough (the
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exact value depends on the compression method), inflateInit determines the
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compression method from the zlib header and allocates all data structures
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accordingly; otherwise the allocation will be deferred to the first call of
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inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
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use default allocation functions.
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the caller. In the current version of inflate, the provide input is not
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read or consumed. Any memory allocation will be deferred to the first call
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of inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them
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to use default allocation functions.
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
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memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
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version assumed by the caller, or Z_STREAM_ERROR if the parameters are
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invalid, such as a null pointer to the structure. msg is set to null if
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there is no error message. inflateInit does not perform any decompression
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apart from possibly reading the zlib header if present: actual decompression
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will be done by inflate(). (So next_in and avail_in may be modified, but
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next_out and avail_out are unused and unchanged.) The current implementation
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of inflateInit() does not process any header information -- that is deferred
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until inflate() is called.
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there is no error message. inflateInit does not perform any decompression.
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Actual decompression will be done by inflate(). So next_in, and avail_in,
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next_out, and avail_out are unused and unchanged. The current
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implementation of inflateInit() does not process any header information --
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that is deferred until inflate() is called.
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*/
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@ -401,17 +408,20 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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- Decompress more input starting at next_in and update next_in and avail_in
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accordingly. If not all input can be processed (because there is not
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enough room in the output buffer), next_in is updated and processing will
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resume at this point for the next call of inflate().
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enough room in the output buffer), then next_in and avail_on are updated
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accordingly, and processing will resume at this point for the next call of
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inflate().
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- Provide more output starting at next_out and update next_out and avail_out
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- Generate more output starting at next_out and update next_out and avail_out
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accordingly. inflate() provides as much output as possible, until there is
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no more input data or no more space in the output buffer (see below about
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the flush parameter).
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Before the call of inflate(), the application should ensure that at least
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one of the actions is possible, by providing more input and/or consuming more
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output, and updating the next_* and avail_* values accordingly. The
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output, and updating the next_* and avail_* values accordingly. If the
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caller of inflate() does not provide both available input and available
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output space, it is possible that there will be no progress made. The
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application can consume the uncompressed output when it wants, for example
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when the output buffer is full (avail_out == 0), or after each call of
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inflate(). If inflate returns Z_OK and with zero avail_out, it must be
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@ -428,7 +438,7 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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gets to the end of that block, or when it runs out of data.
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The Z_BLOCK option assists in appending to or combining deflate streams.
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Also to assist in this, on return inflate() will set strm->data_type to the
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To assist in this, on return inflate() always sets strm->data_type to the
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number of unused bits in the last byte taken from strm->next_in, plus 64 if
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inflate() is currently decoding the last block in the deflate stream, plus
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128 if inflate() returned immediately after decoding an end-of-block code or
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@ -454,7 +464,7 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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this case all pending input is processed and all pending output is flushed;
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avail_out must be large enough to hold all of the uncompressed data for the
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operation to complete. (The size of the uncompressed data may have been
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saved by the compressor for this purpose.) The use of Z_FINISH is not
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saved by the compressor for this purpose.) The use of Z_FINISH is not
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required to perform an inflation in one step. However it may be used to
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inform inflate that a faster approach can be used for the single inflate()
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call. Z_FINISH also informs inflate to not maintain a sliding window if the
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@ -476,32 +486,33 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
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chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
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strm->adler to the Adler-32 checksum of all output produced so far (that is,
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total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
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below. At the end of the stream, inflate() checks that its computed adler32
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below. At the end of the stream, inflate() checks that its computed Adler-32
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checksum is equal to that saved by the compressor and returns Z_STREAM_END
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only if the checksum is correct.
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inflate() can decompress and check either zlib-wrapped or gzip-wrapped
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deflate data. The header type is detected automatically, if requested when
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initializing with inflateInit2(). Any information contained in the gzip
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header is not retained, so applications that need that information should
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instead use raw inflate, see inflateInit2() below, or inflateBack() and
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perform their own processing of the gzip header and trailer. When processing
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header is not retained unless inflateGetHeader() is used. When processing
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gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
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produced so far. The CRC-32 is checked against the gzip trailer.
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produced so far. The CRC-32 is checked against the gzip trailer, as is the
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uncompressed length, modulo 2^32.
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inflate() returns Z_OK if some progress has been made (more input processed
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or more output produced), Z_STREAM_END if the end of the compressed data has
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been reached and all uncompressed output has been produced, Z_NEED_DICT if a
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preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
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corrupted (input stream not conforming to the zlib format or incorrect check
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value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
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next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory,
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Z_BUF_ERROR if no progress is possible or if there was not enough room in the
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output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
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value, in which case strm->msg points to a string with a more specific
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error), Z_STREAM_ERROR if the stream structure was inconsistent (for example
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next_in or next_out was Z_NULL, or the state was inadvertently written over
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by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR
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if no progress was possible or if there was not enough room in the output
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buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
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inflate() can be called again with more input and more output space to
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continue decompressing. If Z_DATA_ERROR is returned, the application may
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then call inflateSync() to look for a good compression block if a partial
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recovery of the data is desired.
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recovery of the data is to be attempted.
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*/
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@ -511,9 +522,8 @@ ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
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This function discards any unprocessed input and does not flush any pending
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output.
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inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
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was inconsistent. In the error case, msg may be set but then points to a
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static string (which must not be deallocated).
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inflateEnd returns Z_OK if success, or Z_STREAM_ERROR if the stream state
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was inconsistent.
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*/
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@ -554,14 +564,15 @@ ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
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windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
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determines the window size. deflate() will then generate raw deflate data
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with no zlib header or trailer, and will not compute an adler32 check value.
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with no zlib header or trailer, and will not compute a check value.
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windowBits can also be greater than 15 for optional gzip encoding. Add
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16 to windowBits to write a simple gzip header and trailer around the
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compressed data instead of a zlib wrapper. The gzip header will have no
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file name, no extra data, no comment, no modification time (set to zero), no
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header crc, and the operating system will be set to 255 (unknown). If a
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gzip stream is being written, strm->adler is a crc32 instead of an adler32.
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header crc, and the operating system will be set to the appropriate value,
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if the operating system was determined at compile time. If a gzip stream is
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being written, strm->adler is a CRC-32 instead of an Adler-32.
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For raw deflate or gzip encoding, a request for a 256-byte window is
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rejected as invalid, since only the zlib header provides a means of
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@ -626,12 +637,12 @@ ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
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addition, the current implementation of deflate will use at most the window
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size minus 262 bytes of the provided dictionary.
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Upon return of this function, strm->adler is set to the adler32 value
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Upon return of this function, strm->adler is set to the Adler-32 value
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of the dictionary; the decompressor may later use this value to determine
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which dictionary has been used by the compressor. (The adler32 value
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which dictionary has been used by the compressor. (The Adler-32 value
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applies to the whole dictionary even if only a subset of the dictionary is
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actually used by the compressor.) If a raw deflate was requested, then the
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adler32 value is not computed and strm->adler is not set.
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Adler-32 value is not computed and strm->adler is not set.
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deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
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parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
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@ -819,7 +830,7 @@ ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
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is for use with other formats that use the deflate compressed data format
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such as zip. Those formats provide their own check values. If a custom
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format is developed using the raw deflate format for compressed data, it is
|
||||
recommended that a check value such as an adler32 or a crc32 be applied to
|
||||
recommended that a check value such as an Adler-32 or a CRC-32 be applied to
|
||||
the uncompressed data as is done in the zlib, gzip, and zip formats. For
|
||||
most applications, the zlib format should be used as is. Note that comments
|
||||
above on the use in deflateInit2() applies to the magnitude of windowBits.
|
||||
@ -828,7 +839,10 @@ ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
|
||||
32 to windowBits to enable zlib and gzip decoding with automatic header
|
||||
detection, or add 16 to decode only the gzip format (the zlib format will
|
||||
return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
|
||||
crc32 instead of an adler32.
|
||||
CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see
|
||||
below), inflate() will not automatically decode concatenated gzip streams.
|
||||
inflate() will return Z_STREAM_END at the end of the gzip stream. The state
|
||||
would need to be reset to continue decoding a subsequent gzip stream.
|
||||
|
||||
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
|
||||
memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
|
||||
@ -849,7 +863,7 @@ ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
|
||||
Initializes the decompression dictionary from the given uncompressed byte
|
||||
sequence. This function must be called immediately after a call of inflate,
|
||||
if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
|
||||
can be determined from the adler32 value returned by that call of inflate.
|
||||
can be determined from the Adler-32 value returned by that call of inflate.
|
||||
The compressor and decompressor must use exactly the same dictionary (see
|
||||
deflateSetDictionary). For raw inflate, this function can be called at any
|
||||
time to set the dictionary. If the provided dictionary is smaller than the
|
||||
@ -860,7 +874,7 @@ ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
|
||||
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
|
||||
parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is
|
||||
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
|
||||
expected one (incorrect adler32 value). inflateSetDictionary does not
|
||||
expected one (incorrect Adler-32 value). inflateSetDictionary does not
|
||||
perform any decompression: this will be done by subsequent calls of
|
||||
inflate().
|
||||
*/
|
||||
@ -918,7 +932,7 @@ ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
|
||||
ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
|
||||
/*
|
||||
This function is equivalent to inflateEnd followed by inflateInit,
|
||||
but does not free and reallocate all the internal decompression state. The
|
||||
but does not free and reallocate the internal decompression state. The
|
||||
stream will keep attributes that may have been set by inflateInit2.
|
||||
|
||||
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
|
||||
@ -930,7 +944,9 @@ ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
|
||||
/*
|
||||
This function is the same as inflateReset, but it also permits changing
|
||||
the wrap and window size requests. The windowBits parameter is interpreted
|
||||
the same as it is for inflateInit2.
|
||||
the same as it is for inflateInit2. If the window size is changed, then the
|
||||
memory allocated for the window is freed, and the window will be reallocated
|
||||
by inflate() if needed.
|
||||
|
||||
inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
|
||||
stream state was inconsistent (such as zalloc or state being Z_NULL), or if
|
||||
@ -982,7 +998,7 @@ ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
|
||||
location in the input stream can be determined from avail_in and data_type
|
||||
as noted in the description for the Z_BLOCK flush parameter for inflate.
|
||||
|
||||
inflateMark returns the value noted above or -65536 if the provided
|
||||
inflateMark returns the value noted above, or -65536 if the provided
|
||||
source stream state was inconsistent.
|
||||
*/
|
||||
|
||||
@ -1074,9 +1090,9 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
||||
This routine would normally be used in a utility that reads zip or gzip
|
||||
files and writes out uncompressed files. The utility would decode the
|
||||
header and process the trailer on its own, hence this routine expects only
|
||||
the raw deflate stream to decompress. This is different from the normal
|
||||
behavior of inflate(), which expects either a zlib or gzip header and
|
||||
trailer around the deflate stream.
|
||||
the raw deflate stream to decompress. This is different from the default
|
||||
behavior of inflate(), which expects a zlib header and trailer around the
|
||||
deflate stream.
|
||||
|
||||
inflateBack() uses two subroutines supplied by the caller that are then
|
||||
called by inflateBack() for input and output. inflateBack() calls those
|
||||
@ -1085,12 +1101,12 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
||||
parameters and return types are defined above in the in_func and out_func
|
||||
typedefs. inflateBack() will call in(in_desc, &buf) which should return the
|
||||
number of bytes of provided input, and a pointer to that input in buf. If
|
||||
there is no input available, in() must return zero--buf is ignored in that
|
||||
case--and inflateBack() will return a buffer error. inflateBack() will call
|
||||
out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
|
||||
should return zero on success, or non-zero on failure. If out() returns
|
||||
non-zero, inflateBack() will return with an error. Neither in() nor out()
|
||||
are permitted to change the contents of the window provided to
|
||||
there is no input available, in() must return zero -- buf is ignored in that
|
||||
case -- and inflateBack() will return a buffer error. inflateBack() will
|
||||
call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
|
||||
out() should return zero on success, or non-zero on failure. If out()
|
||||
returns non-zero, inflateBack() will return with an error. Neither in() nor
|
||||
out() are permitted to change the contents of the window provided to
|
||||
inflateBackInit(), which is also the buffer that out() uses to write from.
|
||||
The length written by out() will be at most the window size. Any non-zero
|
||||
amount of input may be provided by in().
|
||||
@ -1118,7 +1134,7 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
||||
using strm->next_in which will be Z_NULL only if in() returned an error. If
|
||||
strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
|
||||
non-zero. (in() will always be called before out(), so strm->next_in is
|
||||
assured to be defined if out() returns non-zero.) Note that inflateBack()
|
||||
assured to be defined if out() returns non-zero.) Note that inflateBack()
|
||||
cannot return Z_OK.
|
||||
*/
|
||||
|
||||
@ -1598,7 +1614,7 @@ ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
|
||||
return the updated checksum. If buf is Z_NULL, this function returns the
|
||||
required initial value for the checksum.
|
||||
|
||||
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
|
||||
An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
|
||||
much faster.
|
||||
|
||||
Usage example:
|
||||
|
||||
Loading…
Reference in New Issue
Block a user