sl@0: /**
sl@0: @file
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0:
sl@0: /* zlib.h -- interface of the 'zlib' general purpose compression library
sl@0: version 1.2.3, July 18th, 2005
sl@0:
sl@0: Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
sl@0:
sl@0: This software is provided 'as-is', without any express or implied
sl@0: warranty. In no event will the authors be held liable for any damages
sl@0: arising from the use of this software.
sl@0:
sl@0: Permission is granted to anyone to use this software for any purpose,
sl@0: including commercial applications, and to alter it and redistribute it
sl@0: freely, subject to the following restrictions:
sl@0:
sl@0: 1. The origin of this software must not be misrepresented; you must not
sl@0: claim that you wrote the original software. If you use this software
sl@0: in a product, an acknowledgment in the product documentation would be
sl@0: appreciated but is not required.
sl@0: 2. Altered source versions must be plainly marked as such, and must not be
sl@0: misrepresented as being the original software.
sl@0: 3. This notice may not be removed or altered from any source distribution.
sl@0:
sl@0: Jean-loup Gailly Mark Adler
sl@0: jloup@gzip.org madler@alumni.caltech.edu
sl@0:
sl@0:
sl@0: The data format used by the zlib library is described by RFCs (Request for
sl@0: Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
sl@0: (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
sl@0: */
sl@0:
sl@0:
sl@0: #ifndef _ZLIB_H
sl@0: #define _ZLIB_H
sl@0:
sl@0: #if (defined(__TOOLS2__) || defined(__TOOLS__))
sl@0: // A tools build picks up the zconf.h file from the user include path
sl@0: #include "zconf.h"
sl@0: #else
sl@0: // Any other build picks up zconf.h from stdapis system include directory
sl@0: #include <zconf.h>
sl@0: #endif
sl@0:
sl@0: #ifdef __cplusplus
sl@0: extern "C" {
sl@0: #endif
sl@0:
sl@0: /** Zlib version */
sl@0: #define ZLIB_VERSION "1.2.3"
sl@0: /** Zlib version Number */
sl@0: #define ZLIB_VERNUM 0x1230
sl@0:
sl@0: /**
sl@0: The 'zlib' compression library provides in-memory compression and
sl@0: decompression functions, including integrity checks of the uncompressed
sl@0: data. This version of the library supports only one compression method
sl@0: (deflation) but other algorithms will be added later and will have the same
sl@0: stream interface.
sl@0:
sl@0: Compression can be done in a single step if the buffers are large
sl@0: enough (for example if an input file is mmap'ed), or can be done by
sl@0: repeated calls of the compression function. In the latter case, the
sl@0: application must provide more input and/or consume the output
sl@0: (providing more output space) before each call.
sl@0:
sl@0: The compressed data format used by default by the in-memory functions is
sl@0: the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
sl@0: around a deflate stream, which is itself documented in RFC 1951.
sl@0:
sl@0: The library also supports reading and writing files in gzip (.gz) format
sl@0: with an interface similar to that of stdio using the functions that start
sl@0: with "gz". The gzip format is different from the zlib format. gzip is a
sl@0: gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.
sl@0:
sl@0: This library can optionally read and write gzip streams in memory as well.
sl@0:
sl@0: The zlib format was designed to be compact and fast for use in memory
sl@0: and on communications channels. The gzip format was designed for single-
sl@0: file compression on file systems, has a larger header than zlib to maintain
sl@0: directory information, and uses a different, slower check method than zlib.
sl@0:
sl@0: The library does not install any signal handler. The decoder checks
sl@0: the consistency of the compressed data, so the library should never
sl@0: crash even in case of corrupted input.
sl@0: */
sl@0:
sl@0: /** Function pointer - used to allocate the internal state */
sl@0: typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
sl@0: /** Function pointer - used to free the internal state */
sl@0: typedef void (*free_func) OF((voidpf opaque, voidpf address));
sl@0:
sl@0: struct internal_state;
sl@0:
sl@0: /**
sl@0: Encapsulates a zip stream
sl@0: */
sl@0: typedef struct z_stream_s {
sl@0: /** Next input byte */
sl@0: Bytef *next_in;
sl@0: /** Number of bytes available at next_in */
sl@0: uInt avail_in;
sl@0: /** Total nb of input bytes read so far */
sl@0: uLong total_in;
sl@0:
sl@0: /** Next output byte should be put there */
sl@0: Bytef *next_out;
sl@0: /** Remaining free space at next_out */
sl@0: uInt avail_out;
sl@0: /** Total nb of bytes output so far */
sl@0: uLong total_out;
sl@0:
sl@0: /** Last error message, NULL if no error */
sl@0: char *msg;
sl@0: /** Not visible by applications */
sl@0: struct internal_state FAR *state;
sl@0:
sl@0: /** Used to allocate the internal state */
sl@0: alloc_func zalloc;
sl@0: /** Used to free the internal state */
sl@0: free_func zfree;
sl@0: /** Private data object passed to zalloc and zfree */
sl@0: voidpf opaque;
sl@0:
sl@0: /** Best guess about the data type: binary or text */
sl@0: int data_type;
sl@0: /** Adler32 value of the uncompressed data */
sl@0: uLong adler;
sl@0: /** Reserved for future use */
sl@0: uLong reserved;
sl@0: } z_stream;
sl@0:
sl@0: /** typedef z_stream* as z_streamp. Refer to z_stream_s for more details */
sl@0: typedef z_stream FAR *z_streamp;
sl@0:
sl@0: /**
sl@0: gzip header information passed to and from zlib routines. See RFC 1952
sl@0: for more details on the meanings of these fields.
sl@0: */
sl@0: typedef struct gz_header_s {
sl@0: /** True if compressed data believed to be text */
sl@0: int text;
sl@0: /** Modification time */
sl@0: uLong time;
sl@0: /** Extra flags (not used when writing a gzip file) */
sl@0: int xflags;
sl@0: /** Operating system */
sl@0: int os;
sl@0: /** Pointer to extra field or Z_NULL if none */
sl@0: Bytef *extra;
sl@0: /** Extra field length (valid if extra != Z_NULL) */
sl@0: uInt extra_len;
sl@0: /** Space at extra (only when reading header) */
sl@0: uInt extra_max;
sl@0: /** Pointer to zero-terminated file name or Z_NULL */
sl@0: Bytef *name;
sl@0: /** Space at name (only when reading header) */
sl@0: uInt name_max;
sl@0: /** Pointer to zero-terminated comment or Z_NULL */
sl@0: Bytef *comment;
sl@0: /** Space at comment (only when reading header) */
sl@0: uInt comm_max;
sl@0: /** True if there was or will be a header crc */
sl@0: int hcrc;
sl@0: /** True when done reading gzip header (not used when writing a gzip file) */
sl@0: int done;
sl@0: } gz_header;
sl@0:
sl@0: /** gz_headerp is typedef gz_header* */
sl@0: typedef gz_header FAR *gz_headerp;
sl@0:
sl@0: /*
sl@0: The application must update next_in and avail_in when avail_in has
sl@0: dropped to zero. It must update next_out and avail_out when avail_out
sl@0: has dropped to zero. The application must initialize zalloc, zfree and
sl@0: opaque before calling the init function. All other fields are set by the
sl@0: compression library and must not be updated by the application.
sl@0:
sl@0: The opaque value provided by the application will be passed as the first
sl@0: parameter for calls of zalloc and zfree. This can be useful for custom
sl@0: memory management. The compression library attaches no meaning to the
sl@0: opaque value.
sl@0:
sl@0: zalloc must return Z_NULL if there is not enough memory for the object.
sl@0: If zlib is used in a multi-threaded application, zalloc and zfree must be
sl@0: thread safe.
sl@0:
sl@0: On 16-bit systems, the functions zalloc and zfree must be able to allocate
sl@0: exactly 65536 bytes, but will not be required to allocate more than this
sl@0: if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
sl@0: pointers returned by zalloc for objects of exactly 65536 bytes *must*
sl@0: have their offset normalized to zero. The default allocation function
sl@0: provided by this library ensures this (see zutil.c). To reduce memory
sl@0: requirements and avoid any allocation of 64K objects, at the expense of
sl@0: compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
sl@0:
sl@0: The fields total_in and total_out can be used for statistics or
sl@0: progress reports. After compression, total_in holds the total size of
sl@0: the uncompressed data and may be saved for use in the decompressor
sl@0: (particularly if the decompressor wants to decompress everything in
sl@0: a single step).
sl@0: */
sl@0:
sl@0: /* constants */
sl@0:
sl@0: /** Allowed flush values; see deflate() and inflate() below for details */
sl@0: #define Z_NO_FLUSH 0
sl@0: /** Allowed flush values; see deflate() and inflate() below for details. This constant will be removed, use Z_SYNC_FLUSH instead*/
sl@0: #define Z_PARTIAL_FLUSH 1
sl@0: /** Allowed flush values; see deflate() and inflate() below for details */
sl@0: #define Z_SYNC_FLUSH 2
sl@0: /** Allowed flush values; see deflate() and inflate() below for details */
sl@0: #define Z_FULL_FLUSH 3
sl@0: /** Allowed flush values; see deflate() and inflate() below for details */
sl@0: #define Z_FINISH 4
sl@0: /** Allowed flush values; see deflate() and inflate() below for details */
sl@0: #define Z_BLOCK 5
sl@0:
sl@0:
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_OK 0
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_STREAM_END 1
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_NEED_DICT 2
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_ERRNO (-1)
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_STREAM_ERROR (-2)
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_DATA_ERROR (-3)
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_MEM_ERROR (-4)
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_BUF_ERROR (-5)
sl@0: /** Return codes for the compression/decompression functions. Negative
sl@0: values are errors, positive values are used for special but normal events. */
sl@0: #define Z_VERSION_ERROR (-6)
sl@0:
sl@0:
sl@0: /** Compression level as no compression */
sl@0: #define Z_NO_COMPRESSION 0
sl@0: /** Compression level for best speed */
sl@0: #define Z_BEST_SPEED 1
sl@0: /** Compression level for best compression */
sl@0: #define Z_BEST_COMPRESSION 9
sl@0: /** Compression level for default compression */
sl@0: #define Z_DEFAULT_COMPRESSION (-1)
sl@0:
sl@0:
sl@0: /** Compression strategy; see deflateInit2() below for details */
sl@0: #define Z_FILTERED 1
sl@0: /** Compression strategy; see deflateInit2() below for details */
sl@0: #define Z_HUFFMAN_ONLY 2
sl@0: /** Compression strategy; see deflateInit2() below for details */
sl@0: #define Z_RLE 3
sl@0: /** Compression strategy; see deflateInit2() below for details */
sl@0: #define Z_FIXED 4
sl@0: /** Compression strategy; see deflateInit2() below for details */
sl@0: #define Z_DEFAULT_STRATEGY 0
sl@0:
sl@0:
sl@0: /** Possible values of the data_type field (though see inflate()) */
sl@0: #define Z_BINARY 0
sl@0: /** Possible values of the data_type field (though see inflate()) */
sl@0: #define Z_TEXT 1
sl@0: /** Possible values of the data_type field (though see inflate()). It is used for compatibility with 1.2.2 and earlier */
sl@0: #define Z_ASCII Z_TEXT
sl@0: /** Possible values of the data_type field (though see inflate()) */
sl@0: #define Z_UNKNOWN 2
sl@0:
sl@0:
sl@0: /** The deflate compression method (the only one supported in this version) */
sl@0: #define Z_DEFLATED 8
sl@0:
sl@0: /** For initializing zalloc, zfree, opaque */
sl@0: #define Z_NULL 0
sl@0:
sl@0: /** For compatibility with versions < 1.0.2 */
sl@0: #define zlib_version zlibVersion()
sl@0:
sl@0:
sl@0: /* basic functions */
sl@0:
sl@0: /** The application can compare zlibVersion and ZLIB_VERSION for consistency.
sl@0: If the first character differs, the library code actually used is
sl@0: not compatible with the zlib.h header file used by the application.
sl@0: This check is automatically made by deflateInit and inflateInit.
sl@0: @return returns zlib version
sl@0: */
sl@0: ZEXTERN const char * ZEXPORT zlibVersion OF((void));
sl@0:
sl@0: /*
sl@0: ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));
sl@0:
sl@0: Initializes the internal stream state for compression. The fields
sl@0: zalloc, zfree and opaque must be initialized before by the caller.
sl@0: If zalloc and zfree are set to Z_NULL, deflateInit updates them to
sl@0: use default allocation functions.
sl@0:
sl@0: The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
sl@0: 1 gives best speed, 9 gives best compression, 0 gives no compression at
sl@0: all (the input data is simply copied a block at a time).
sl@0: Z_DEFAULT_COMPRESSION requests a default compromise between speed and
sl@0: compression (currently equivalent to level 6).
sl@0:
sl@0: deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_STREAM_ERROR if level is not a valid compression level,
sl@0: Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
sl@0: with the version assumed by the caller (ZLIB_VERSION).
sl@0: msg is set to null if there is no error message. deflateInit does not
sl@0: perform any compression: this will be done by deflate().
sl@0: */
sl@0:
sl@0: /**
sl@0: deflate compresses as much data as possible, and stops when the input
sl@0: buffer becomes empty or the output buffer becomes full. It may introduce some
sl@0: output latency (reading input without producing any output) except when
sl@0: forced to flush.
sl@0:
sl@0: The detailed semantics are as follows. deflate performs one or both of the
sl@0: following actions:
sl@0:
sl@0: - Compress more input starting at next_in and update next_in and avail_in
sl@0: accordingly. If not all input can be processed (because there is not
sl@0: enough room in the output buffer), next_in and avail_in are updated and
sl@0: processing will resume at this point for the next call of deflate().
sl@0:
sl@0: - Provide more output starting at next_out and update next_out and avail_out
sl@0: accordingly. This action is forced if the parameter flush is non zero.
sl@0: Forcing flush frequently degrades the compression ratio, so this parameter
sl@0: should be set only when necessary (in interactive applications).
sl@0: Some output may be provided even if flush is not set.
sl@0:
sl@0: Before the call of deflate(), the application should ensure that at least
sl@0: one of the actions is possible, by providing more input and/or consuming
sl@0: more output, and updating avail_in or avail_out accordingly; avail_out
sl@0: should never be zero before the call. The application can consume the
sl@0: compressed output when it wants, for example when the output buffer is full
sl@0: (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
sl@0: and with zero avail_out, it must be called again after making room in the
sl@0: output buffer because there might be more output pending.
sl@0:
sl@0: Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
sl@0: decide how much data to accumualte before producing output, in order to
sl@0: maximize compression.
sl@0:
sl@0: If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
sl@0: flushed to the output buffer and the output is aligned on a byte boundary, so
sl@0: that the decompressor can get all input data available so far. (In particular
sl@0: avail_in is zero after the call if enough output space has been provided
sl@0: before the call.) Flushing may degrade compression for some compression
sl@0: algorithms and so it should be used only when necessary.
sl@0:
sl@0: If flush is set to Z_FULL_FLUSH, all output is flushed as with
sl@0: Z_SYNC_FLUSH, and the compression state is reset so that decompression can
sl@0: restart from this point if previous compressed data has been damaged or if
sl@0: random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
sl@0: compression.
sl@0:
sl@0: If deflate returns with avail_out == 0, this function must be called again
sl@0: with the same value of the flush parameter and more output space (updated
sl@0: avail_out), until the flush is complete (deflate returns with non-zero
sl@0: avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
sl@0: avail_out is greater than six to avoid repeated flush markers due to
sl@0: avail_out == 0 on return.
sl@0:
sl@0: If the parameter flush is set to Z_FINISH, pending input is processed,
sl@0: pending output is flushed and deflate returns with Z_STREAM_END if there
sl@0: was enough output space; if deflate returns with Z_OK, this function must be
sl@0: called again with Z_FINISH and more output space (updated avail_out) but no
sl@0: more input data, until it returns with Z_STREAM_END or an error. After
sl@0: deflate has returned Z_STREAM_END, the only possible operations on the
sl@0: stream are deflateReset or deflateEnd.
sl@0:
sl@0: Z_FINISH can be used immediately after deflateInit if all the compression
sl@0: is to be done in a single step. In this case, avail_out must be at least
sl@0: the value returned by deflateBound (see below). If deflate does not return
sl@0: Z_STREAM_END, then it must be called again as described above.
sl@0:
sl@0: deflate() sets strm->adler to the adler32 checksum of all input read
sl@0: so far (that is, total_in bytes).
sl@0:
sl@0: deflate() may update strm->data_type if it can make a good guess about
sl@0: the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered
sl@0: binary. This field is only for information purposes and does not affect
sl@0: the compression algorithm in any manner.
sl@0:
sl@0: deflate() returns Z_OK if some progress has been made (more input
sl@0: processed or more output produced), Z_STREAM_END if all input has been
sl@0: consumed and all output has been produced (only when flush is set to
sl@0: Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
sl@0: if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
sl@0: (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not
sl@0: fatal, and deflate() can be called again with more input and more output
sl@0: space to continue compressing.
sl@0:
sl@0: @param strm Stream of data
sl@0: @param flush Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
sl@0: decide how much data to accumualte before producing output, in order to
sl@0: maximize compression. Refer to the description above for more details.
sl@0: @return deflate returns Z_OK on success. Refer to the description above for more details.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
sl@0:
sl@0: /**
sl@0: All dynamically allocated data structures for this stream are freed.
sl@0: This function discards any unprocessed input and does not flush any
sl@0: pending output.
sl@0:
sl@0: deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
sl@0: stream state was inconsistent, Z_DATA_ERROR if the stream was freed
sl@0: prematurely (some input or output was discarded). In the error case,
sl@0: msg may be set but then points to a static string (which must not be
sl@0: deallocated).
sl@0:
sl@0: @param strm Stream of data
sl@0: @return deflateEnd returns Z_OK on success. Refer to the description above for more details.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
sl@0:
sl@0: /*
sl@0: ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
sl@0:
sl@0: Initializes the internal stream state for decompression. The fields
sl@0: next_in, avail_in, zalloc, zfree and opaque must be initialized before by
sl@0: the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
sl@0: value depends on the compression method), inflateInit determines the
sl@0: compression method from the zlib header and allocates all data structures
sl@0: accordingly; otherwise the allocation will be deferred to the first call of
sl@0: inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
sl@0: use default allocation functions.
sl@0:
sl@0: inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
sl@0: version assumed by the caller. msg is set to null if there is no error
sl@0: message. inflateInit does not perform any decompression apart from reading
sl@0: the zlib header if present: this will be done by inflate(). (So next_in and
sl@0: avail_in may be modified, but next_out and avail_out are unchanged.)
sl@0: */
sl@0:
sl@0: /**
sl@0: inflate decompresses as much data as possible, and stops when the input
sl@0: buffer becomes empty or the output buffer becomes full. It may introduce
sl@0: some output latency (reading input without producing any output) except when
sl@0: forced to flush.
sl@0:
sl@0: The detailed semantics are as follows. inflate performs one or both of the
sl@0: following actions:
sl@0:
sl@0: - Decompress more input starting at next_in and update next_in and avail_in
sl@0: accordingly. If not all input can be processed (because there is not
sl@0: enough room in the output buffer), next_in is updated and processing
sl@0: will resume at this point for the next call of inflate().
sl@0:
sl@0: - Provide more output starting at next_out and update next_out and avail_out
sl@0: accordingly. inflate() provides as much output as possible, until there
sl@0: is no more input data or no more space in the output buffer (see below
sl@0: about the flush parameter).
sl@0:
sl@0: Before the call of inflate(), the application should ensure that at least
sl@0: one of the actions is possible, by providing more input and/or consuming
sl@0: more output, and updating the next_* and avail_* values accordingly.
sl@0: The application can consume the uncompressed output when it wants, for
sl@0: example when the output buffer is full (avail_out == 0), or after each
sl@0: call of inflate(). If inflate returns Z_OK and with zero avail_out, it
sl@0: must be called again after making room in the output buffer because there
sl@0: might be more output pending.
sl@0:
sl@0: The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
sl@0: Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
sl@0: output as possible to the output buffer. Z_BLOCK requests that inflate() stop
sl@0: if and when it gets to the next deflate block boundary. When decoding the
sl@0: zlib or gzip format, this will cause inflate() to return immediately after
sl@0: the header and before the first block. When doing a raw inflate, inflate()
sl@0: will go ahead and process the first block, and will return when it gets to
sl@0: the end of that block, or when it runs out of data.
sl@0:
sl@0: The Z_BLOCK option assists in appending to or combining deflate streams.
sl@0: Also to assist in this, on return inflate() will set strm->data_type to the
sl@0: number of unused bits in the last byte taken from strm->next_in, plus 64
sl@0: if inflate() is currently decoding the last block in the deflate stream,
sl@0: plus 128 if inflate() returned immediately after decoding an end-of-block
sl@0: code or decoding the complete header up to just before the first byte of the
sl@0: deflate stream. The end-of-block will not be indicated until all of the
sl@0: uncompressed data from that block has been written to strm->next_out. The
sl@0: number of unused bits may in general be greater than seven, except when
sl@0: bit 7 of data_type is set, in which case the number of unused bits will be
sl@0: less than eight.
sl@0:
sl@0: inflate() should normally be called until it returns Z_STREAM_END or an
sl@0: error. However if all decompression is to be performed in a single step
sl@0: (a single call of inflate), the parameter flush should be set to
sl@0: Z_FINISH. In this case all pending input is processed and all pending
sl@0: output is flushed; avail_out must be large enough to hold all the
sl@0: uncompressed data. (The size of the uncompressed data may have been saved
sl@0: by the compressor for this purpose.) The next operation on this stream must
sl@0: be inflateEnd to deallocate the decompression state. The use of Z_FINISH
sl@0: is never required, but can be used to inform inflate that a faster approach
sl@0: may be used for the single inflate() call.
sl@0:
sl@0: In this implementation, inflate() always flushes as much output as
sl@0: possible to the output buffer, and always uses the faster approach on the
sl@0: first call. So the only effect of the flush parameter in this implementation
sl@0: is on the return value of inflate(), as noted below, or when it returns early
sl@0: because Z_BLOCK is used.
sl@0:
sl@0: If a preset dictionary is needed after this call (see inflateSetDictionary
sl@0: below), inflate sets strm->adler to the adler32 checksum of the dictionary
sl@0: chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
sl@0: strm->adler to the adler32 checksum of all output produced so far (that is,
sl@0: total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
sl@0: below. At the end of the stream, inflate() checks that its computed adler32
sl@0: checksum is equal to that saved by the compressor and returns Z_STREAM_END
sl@0: only if the checksum is correct.
sl@0:
sl@0: inflate() will decompress and check either zlib-wrapped or gzip-wrapped
sl@0: deflate data. The header type is detected automatically. Any information
sl@0: contained in the gzip header is not retained, so applications that need that
sl@0: information should instead use raw inflate, see inflateInit2() below, or
sl@0: inflateBack() and perform their own processing of the gzip header and
sl@0: trailer.
sl@0:
sl@0: inflate() returns Z_OK if some progress has been made (more input processed
sl@0: or more output produced), Z_STREAM_END if the end of the compressed data has
sl@0: been reached and all uncompressed output has been produced, Z_NEED_DICT if a
sl@0: preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
sl@0: corrupted (input stream not conforming to the zlib format or incorrect check
sl@0: value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
sl@0: if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
sl@0: Z_BUF_ERROR if no progress is possible or if there was not enough room in the
sl@0: output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
sl@0: inflate() can be called again with more input and more output space to
sl@0: continue decompressing. If Z_DATA_ERROR is returned, the application may then
sl@0: call inflateSync() to look for a good compression block if a partial recovery
sl@0: of the data is desired.
sl@0:
sl@0: @param strm Stream of data
sl@0: @param flush This parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
sl@0: Z_FINISH, or Z_BLOCK. Refer to the description for more details.
sl@0: @return inflate returns Z_OK on success. Refer to the description above for more details.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));
sl@0:
sl@0: /**
sl@0: All dynamically allocated data structures for this stream are freed.
sl@0: This function discards any unprocessed input and does not flush any
sl@0: pending output.
sl@0:
sl@0: @param strm Stream of data
sl@0: @return inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state
sl@0: was inconsistent. In the error case, msg may be set but then points to a
sl@0: static string (which must not be deallocated).
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
sl@0:
sl@0: /* Advanced functions */
sl@0:
sl@0: /*
sl@0: The following functions are needed only in some special applications.
sl@0: */
sl@0:
sl@0: /*
sl@0: ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
sl@0: int level,
sl@0: int method,
sl@0: int windowBits,
sl@0: int memLevel,
sl@0: int strategy));
sl@0:
sl@0: This is another version of deflateInit with more compression options. The
sl@0: fields next_in, zalloc, zfree and opaque must be initialized before by
sl@0: the caller.
sl@0:
sl@0: The method parameter is the compression method. It must be Z_DEFLATED in
sl@0: this version of the library.
sl@0:
sl@0: The windowBits parameter is the base two logarithm of the window size
sl@0: (the size of the history buffer). It should be in the range 8..15 for this
sl@0: version of the library. Larger values of this parameter result in better
sl@0: compression at the expense of memory usage. The default value is 15 if
sl@0: deflateInit is used instead.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
sl@0: determines the window size. deflate() will then generate raw deflate data
sl@0: with no zlib header or trailer, and will not compute an adler32 check value.
sl@0:
sl@0: windowBits can also be greater than 15 for optional gzip encoding. Add
sl@0: 16 to windowBits to write a simple gzip header and trailer around the
sl@0: compressed data instead of a zlib wrapper. The gzip header will have no
sl@0: file name, no extra data, no comment, no modification time (set to zero),
sl@0: no header crc, and the operating system will be set to 3 (UNIX). If a
sl@0: gzip stream is being written, strm->adler is a crc32 instead of an adler32.
sl@0:
sl@0: The memLevel parameter specifies how much memory should be allocated
sl@0: for the internal compression state. memLevel=1 uses minimum memory but
sl@0: is slow and reduces compression ratio; memLevel=9 uses maximum memory
sl@0: for optimal speed. The default value is 8. See zconf.h for total memory
sl@0: usage as a function of windowBits and memLevel.
sl@0:
sl@0: The strategy parameter is used to tune the compression algorithm. Use the
sl@0: value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
sl@0: filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
sl@0: string match), or Z_RLE to limit match distances to one (run-length
sl@0: encoding). Filtered data consists mostly of small values with a somewhat
sl@0: random distribution. In this case, the compression algorithm is tuned to
sl@0: compress them better. The effect of Z_FILTERED is to force more Huffman
sl@0: coding and less string matching; it is somewhat intermediate between
sl@0: Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
sl@0: Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
sl@0: parameter only affects the compression ratio but not the correctness of the
sl@0: compressed output even if it is not set appropriately. Z_FIXED prevents the
sl@0: use of dynamic Huffman codes, allowing for a simpler decoder for special
sl@0: applications.
sl@0:
sl@0: deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
sl@0: method). msg is set to null if there is no error message. deflateInit2 does
sl@0: not perform any compression: this will be done by deflate().
sl@0: */
sl@0:
sl@0: /**
sl@0: Initializes the compression dictionary from the given byte sequence
sl@0: without producing any compressed output. This function must be called
sl@0: immediately after deflateInit, deflateInit2 or deflateReset, before any
sl@0: call of deflate. The compressor and decompressor must use exactly the same
sl@0: dictionary (see inflateSetDictionary).
sl@0:
sl@0: The dictionary should consist of strings (byte sequences) that are likely
sl@0: to be encountered later in the data to be compressed, with the most commonly
sl@0: used strings preferably put towards the end of the dictionary. Using a
sl@0: dictionary is most useful when the data to be compressed is short and can be
sl@0: predicted with good accuracy; the data can then be compressed better than
sl@0: with the default empty dictionary.
sl@0:
sl@0: Depending on the size of the compression data structures selected by
sl@0: deflateInit or deflateInit2, a part of the dictionary may in effect be
sl@0: discarded, for example if the dictionary is larger than the window size in
sl@0: deflate or deflate2. Thus the strings most likely to be useful should be
sl@0: put at the end of the dictionary, not at the front. In addition, the
sl@0: current implementation of deflate will use at most the window size minus
sl@0: 262 bytes of the provided dictionary.
sl@0:
sl@0: Upon return of this function, strm->adler is set to the adler32 value
sl@0: of the dictionary; the decompressor may later use this value to determine
sl@0: which dictionary has been used by the compressor. (The adler32 value
sl@0: applies to the whole dictionary even if only a subset of the dictionary is
sl@0: actually used by the compressor.) If a raw deflate was requested, then the
sl@0: adler32 value is not computed and strm->adler is not set.
sl@0:
sl@0: @param strm Stream of data
sl@0: @param dictionary Pointer to the dictionary. Refer to the description above for more details.
sl@0: @param dictLength Dictionay Length
sl@0: @return deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
sl@0: parameter is invalid (such as NULL dictionary) or the stream state is
sl@0: inconsistent (for example if deflate has already been called for this stream
sl@0: or if the compression method is bsort). deflateSetDictionary does not
sl@0: perform any compression: this will be done by deflate().
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
sl@0: const Bytef *dictionary,
sl@0: uInt dictLength));
sl@0:
sl@0: /**
sl@0: Sets the destination stream as a complete copy of the source stream.
sl@0:
sl@0: This function can be useful when several compression strategies will be
sl@0: tried, for example when there are several ways of pre-processing the input
sl@0: data with a filter. The streams that will be discarded should then be freed
sl@0: by calling deflateEnd. Note that deflateCopy duplicates the internal
sl@0: compression state which can be quite large, so this strategy is slow and
sl@0: can consume lots of memory.
sl@0:
sl@0: @param dest destination stream
sl@0: @param souce source stream of data
sl@0: @return deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
sl@0: (such as zalloc being NULL). msg is left unchanged in both source and
sl@0: destination.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
sl@0: z_streamp source));
sl@0:
sl@0: /**
sl@0: This function is equivalent to deflateEnd followed by deflateInit,
sl@0: but does not free and reallocate all the internal compression state.
sl@0: The stream will keep the same compression level and any other attributes
sl@0: that may have been set by deflateInit2.
sl@0:
sl@0: @param strm stream of data
sl@0: @return deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent (such as zalloc or state being NULL).
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
sl@0:
sl@0: /**
sl@0: Dynamically update the compression level and compression strategy. The
sl@0: interpretation of level and strategy is as in deflateInit2. This can be
sl@0: used to switch between compression and straight copy of the input data, or
sl@0: to switch to a different kind of input data requiring a different
sl@0: strategy. If the compression level is changed, the input available so far
sl@0: is compressed with the old level (and may be flushed); the new level will
sl@0: take effect only at the next call of deflate().
sl@0:
sl@0: Before the call of deflateParams, the stream state must be set as for
sl@0: a call of deflate(), since the currently available input may have to
sl@0: be compressed and flushed. In particular, strm->avail_out must be non-zero.
sl@0:
sl@0: @param strm stream of data
sl@0: @param level compression level
sl@0: @param strategy compression algorithm
sl@0: @return deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
sl@0: if strm->avail_out was zero.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
sl@0: int level,
sl@0: int strategy));
sl@0:
sl@0: /**
sl@0: Fine tune deflate's internal compression parameters. This should only be
sl@0: used by someone who understands the algorithm used by zlib's deflate for
sl@0: searching for the best matching string, and even then only by the most
sl@0: fanatic optimizer trying to squeeze out the last compressed bit for their
sl@0: specific input data. Read the deflate.c source code for the meaning of the
sl@0: max_lazy, good_length, nice_length, and max_chain parameters.
sl@0:
sl@0: deflateTune() can be called after deflateInit() or deflateInit2()
sl@0:
sl@0: @param strm stream of data
sl@0: @param good_length reduce lazy search above this match length
sl@0: @param max_lazy do not perform lazy search above this match length
sl@0: @param nice_length quit search above this match length
sl@0: @param max_chain
sl@0: @return deflateTune returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
sl@0: int good_length,
sl@0: int max_lazy,
sl@0: int nice_length,
sl@0: int max_chain));
sl@0:
sl@0: /**
sl@0: deflateBound() returns an upper bound on the compressed size after
sl@0: deflation of sourceLen bytes. It must be called after deflateInit()
sl@0: or deflateInit2(). This would be used to allocate an output buffer
sl@0: for deflation in a single pass, and so would be called before deflate().
sl@0:
sl@0: @param strm stream of data
sl@0: @param sourceLen source length
sl@0: @return deflateBound returns an upper bound on the compressed size after
sl@0: deflation of sourceLen bytes.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
sl@0: uLong sourceLen));
sl@0:
sl@0: /**
sl@0: deflatePrime() inserts bits in the deflate output stream. The intent
sl@0: is that this function is used to start off the deflate output with the
sl@0: bits leftover from a previous deflate stream when appending to it. As such,
sl@0: this function can only be used for raw deflate, and must be used before the
sl@0: first deflate() call after a deflateInit2() or deflateReset(). bits must be
sl@0: less than or equal to 16, and that many of the least significant bits of
sl@0: value will be inserted in the output.
sl@0:
sl@0: @param strm stream of data
sl@0: @param bits bits must be less than or equal to 16, and that many of the least
sl@0: significant bits of value will be inserted in the output.
sl@0: @param value represents value of the bits to be inserted
sl@0: @return deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
sl@0: int bits,
sl@0: int value));
sl@0:
sl@0: /**
sl@0: deflateSetHeader() provides gzip header information for when a gzip
sl@0: stream is requested by deflateInit2(). deflateSetHeader() may be called
sl@0: after deflateInit2() or deflateReset() and before the first call of
sl@0: deflate(). The text, time, os, extra field, name, and comment information
sl@0: in the provided gz_header structure are written to the gzip header (xflag is
sl@0: ignored -- the extra flags are set according to the compression level). The
sl@0: caller must assure that, if not Z_NULL, name and comment are terminated with
sl@0: a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
sl@0: available there. If hcrc is true, a gzip header crc is included. Note that
sl@0: the current versions of the command-line version of gzip (up through version
sl@0: 1.3.x) do not support header crc's, and will report that it is a "multi-part
sl@0: gzip file" and give up.
sl@0:
sl@0: If deflateSetHeader is not used, the default gzip header has text false,
sl@0: the time set to zero, and os set to 3, with no extra, name, or comment
sl@0: fields. The gzip header is returned to the default state by deflateReset().
sl@0:
sl@0: @param strm stream of data
sl@0: @param head gzip header
sl@0: @return deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
sl@0: gz_headerp head));
sl@0:
sl@0: /*
sl@0: ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
sl@0: int windowBits));
sl@0:
sl@0: This is another version of inflateInit with an extra parameter. The
sl@0: fields next_in, avail_in, zalloc, zfree and opaque must be initialized
sl@0: before by the caller.
sl@0:
sl@0: The windowBits parameter is the base two logarithm of the maximum window
sl@0: size (the size of the history buffer). It should be in the range 8..15 for
sl@0: this version of the library. The default value is 15 if inflateInit is used
sl@0: instead. windowBits must be greater than or equal to the windowBits value
sl@0: provided to deflateInit2() while compressing, or it must be equal to 15 if
sl@0: deflateInit2() was not used. If a compressed stream with a larger window
sl@0: size is given as input, inflate() will return with the error code
sl@0: Z_DATA_ERROR instead of trying to allocate a larger window.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
sl@0: determines the window size. inflate() will then process raw deflate data,
sl@0: not looking for a zlib or gzip header, not generating a check value, and not
sl@0: looking for any check values for comparison at the end of the stream. This
sl@0: is for use with other formats that use the deflate compressed data format
sl@0: such as zip. Those formats provide their own check values. If a custom
sl@0: format is developed using the raw deflate format for compressed data, it is
sl@0: recommended that a check value such as an adler32 or a crc32 be applied to
sl@0: the uncompressed data as is done in the zlib, gzip, and zip formats. For
sl@0: most applications, the zlib format should be used as is. Note that comments
sl@0: above on the use in deflateInit2() applies to the magnitude of windowBits.
sl@0:
sl@0: windowBits can also be greater than 15 for optional gzip decoding. Add
sl@0: 32 to windowBits to enable zlib and gzip decoding with automatic header
sl@0: detection, or add 16 to decode only the gzip format (the zlib format will
sl@0: return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
sl@0: a crc32 instead of an adler32.
sl@0:
sl@0: inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
sl@0: is set to null if there is no error message. inflateInit2 does not perform
sl@0: any decompression apart from reading the zlib header if present: this will
sl@0: be done by inflate(). (So next_in and avail_in may be modified, but next_out
sl@0: and avail_out are unchanged.)
sl@0: */
sl@0:
sl@0: /**
sl@0: Initializes the decompression dictionary from the given uncompressed byte
sl@0: sequence. This function must be called immediately after a call of inflate,
sl@0: if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
sl@0: can be determined from the adler32 value returned by that call of inflate.
sl@0: The compressor and decompressor must use exactly the same dictionary (see
sl@0: deflateSetDictionary). For raw inflate, this function can be called
sl@0: immediately after inflateInit2() or inflateReset() and before any call of
sl@0: inflate() to set the dictionary. The application must insure that the
sl@0: dictionary that was used for compression is provided.
sl@0:
sl@0: inflateSetDictionary does not perform any decompression: this will be done
sl@0: by subsequent calls of inflate().
sl@0:
sl@0: @param strm stream of data
sl@0: @param dictionary Pointer to dictionary
sl@0: @param dictLength Dictionary Length
sl@0: @return inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
sl@0: parameter is invalid (such as NULL dictionary) or the stream state is
sl@0: inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
sl@0: expected one (incorrect adler32 value).
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
sl@0: const Bytef *dictionary,
sl@0: uInt dictLength));
sl@0:
sl@0: /**
sl@0: Skips invalid compressed data until a full flush point (see above the
sl@0: description of deflate with Z_FULL_FLUSH) can be found, or until all
sl@0: available input is skipped. No output is provided.
sl@0:
sl@0: @param strm Stream of data
sl@0: @return inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR
sl@0: if no more input was provided, Z_DATA_ERROR if no flush point has been found,
sl@0: or Z_STREAM_ERROR if the stream structure was inconsistent. In the success
sl@0: case, the application may save the current current value of total_in which
sl@0: indicates where valid compressed data was found. In the error case, the
sl@0: application may repeatedly call inflateSync, providing more input each time,
sl@0: until success or end of the input data.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
sl@0:
sl@0: /**
sl@0: Sets the destination stream as a complete copy of the source stream.
sl@0:
sl@0: This function can be useful when randomly accessing a large stream. The
sl@0: first pass through the stream can periodically record the inflate state,
sl@0: allowing restarting inflate at those points when randomly accessing the
sl@0: stream.
sl@0:
sl@0: @param dest destination stream
sl@0: @param source source stream of data
sl@0: @return inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
sl@0: (such as zalloc being NULL). msg is left unchanged in both source and
sl@0: destination.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
sl@0: z_streamp source));
sl@0:
sl@0: /**
sl@0: This function is equivalent to inflateEnd followed by inflateInit,
sl@0: but does not free and reallocate all the internal decompression state.
sl@0: The stream will keep attributes that may have been set by inflateInit2.
sl@0:
sl@0: @param strm Stream of data
sl@0: @return inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent (such as zalloc or state being NULL).
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
sl@0:
sl@0: /**
sl@0: This function inserts bits in the inflate input stream. The intent is
sl@0: that this function is used to start inflating at a bit position in the
sl@0: middle of a byte. The provided bits will be used before any bytes are used
sl@0: from next_in. This function should only be used with raw inflate, and
sl@0: should be used before the first inflate() call after inflateInit2() or
sl@0: inflateReset(). bits must be less than or equal to 16, and that many of the
sl@0: least significant bits of value will be inserted in the input.
sl@0:
sl@0: @param strm stream of data
sl@0: @param bits bits must be less than or equal to 16, and that many of the
sl@0: least significant bits of value will be inserted in the input.
sl@0: @param value @param value represents value of the bits to be inserted
sl@0: @return inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
sl@0: int bits,
sl@0: int value));
sl@0:
sl@0: /**
sl@0: inflateGetHeader() requests that gzip header information be stored in the
sl@0: provided gz_header structure. inflateGetHeader() may be called after
sl@0: inflateInit2() or inflateReset(), and before the first call of inflate().
sl@0: As inflate() processes the gzip stream, head->done is zero until the header
sl@0: is completed, at which time head->done is set to one. If a zlib stream is
sl@0: being decoded, then head->done is set to -1 to indicate that there will be
sl@0: no gzip header information forthcoming. Note that Z_BLOCK can be used to
sl@0: force inflate() to return immediately after header processing is complete
sl@0: and before any actual data is decompressed.
sl@0:
sl@0: The text, time, xflags, and os fields are filled in with the gzip header
sl@0: contents. hcrc is set to true if there is a header CRC. (The header CRC
sl@0: was valid if done is set to one.) If extra is not Z_NULL, then extra_max
sl@0: contains the maximum number of bytes to write to extra. Once done is true,
sl@0: extra_len contains the actual extra field length, and extra contains the
sl@0: extra field, or that field truncated if extra_max is less than extra_len.
sl@0: If name is not Z_NULL, then up to name_max characters are written there,
sl@0: terminated with a zero unless the length is greater than name_max. If
sl@0: comment is not Z_NULL, then up to comm_max characters are written there,
sl@0: terminated with a zero unless the length is greater than comm_max. When
sl@0: any of extra, name, or comment are not Z_NULL and the respective field is
sl@0: not present in the header, then that field is set to Z_NULL to signal its
sl@0: absence. This allows the use of deflateSetHeader() with the returned
sl@0: structure to duplicate the header. However if those fields are set to
sl@0: allocated memory, then the application will need to save those pointers
sl@0: elsewhere so that they can be eventually freed.
sl@0:
sl@0: If inflateGetHeader is not used, then the header information is simply
sl@0: discarded. The header is always checked for validity, including the header
sl@0: CRC if present. inflateReset() will reset the process to discard the header
sl@0: information. The application would need to call inflateGetHeader() again to
sl@0: retrieve the header from the next gzip stream.
sl@0:
sl@0: @param stream of data
sl@0: @param head gzip header
sl@0: @return inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
sl@0: stream state was inconsistent.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
sl@0: gz_headerp head));
sl@0:
sl@0: /*
sl@0: ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
sl@0: unsigned char FAR *window));
sl@0:
sl@0: Initialize the internal stream state for decompression using inflateBack()
sl@0: calls. The fields zalloc, zfree and opaque in strm must be initialized
sl@0: before the call. If zalloc and zfree are Z_NULL, then the default library-
sl@0: derived memory allocation routines are used. windowBits is the base two
sl@0: logarithm of the window size, in the range 8..15. window is a caller
sl@0: supplied buffer of that size. Except for special applications where it is
sl@0: assured that deflate was used with small window sizes, windowBits must be 15
sl@0: and a 32K byte window must be supplied to be able to decompress general
sl@0: deflate streams.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: See inflateBack() for the usage of these routines.
sl@0:
sl@0: inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
sl@0: the paramaters are invalid, Z_MEM_ERROR if the internal state could not
sl@0: be allocated, or Z_VERSION_ERROR if the version of the library does not
sl@0: match the version of the header file.
sl@0: */
sl@0:
sl@0: /** Input function pointer defined to be used in inflateBack */
sl@0: typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *));
sl@0: /** Output function pointer defined to be used in inflateBack */
sl@0: typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));
sl@0:
sl@0:
sl@0: /**
sl@0: inflateBack() does a raw inflate with a single call using a call-back
sl@0: interface for input and output. This is more efficient than inflate() for
sl@0: file i/o applications in that it avoids copying between the output and the
sl@0: sliding window by simply making the window itself the output buffer. This
sl@0: function trusts the application to not change the output buffer passed by
sl@0: the output function, at least until inflateBack() returns.
sl@0:
sl@0: inflateBackInit() must be called first to allocate the internal state
sl@0: and to initialize the state with the user-provided window buffer.
sl@0: inflateBack() may then be used multiple times to inflate a complete, raw
sl@0: deflate stream with each call. inflateBackEnd() is then called to free
sl@0: the allocated state.
sl@0:
sl@0: A raw deflate stream is one with no zlib or gzip header or trailer.
sl@0: This routine would normally be used in a utility that reads zip or gzip
sl@0: files and writes out uncompressed files. The utility would decode the
sl@0: header and process the trailer on its own, hence this routine expects
sl@0: only the raw deflate stream to decompress. This is different from the
sl@0: normal behavior of inflate(), which expects either a zlib or gzip header and
sl@0: trailer around the deflate stream.
sl@0:
sl@0: inflateBack() uses two subroutines supplied by the caller that are then
sl@0: called by inflateBack() for input and output. inflateBack() calls those
sl@0: routines until it reads a complete deflate stream and writes out all of the
sl@0: uncompressed data, or until it encounters an error. The function's
sl@0: parameters and return types are defined above in the in_func and out_func
sl@0: typedefs. inflateBack() will call in(in_desc, &buf) which should return the
sl@0: number of bytes of provided input, and a pointer to that input in buf. If
sl@0: there is no input available, in() must return zero--buf is ignored in that
sl@0: case--and inflateBack() will return a buffer error. inflateBack() will call
sl@0: out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out()
sl@0: should return zero on success, or non-zero on failure. If out() returns
sl@0: non-zero, inflateBack() will return with an error. Neither in() nor out()
sl@0: are permitted to change the contents of the window provided to
sl@0: inflateBackInit(), which is also the buffer that out() uses to write from.
sl@0: The length written by out() will be at most the window size. Any non-zero
sl@0: amount of input may be provided by in().
sl@0:
sl@0: For convenience, inflateBack() can be provided input on the first call by
sl@0: setting strm->next_in and strm->avail_in. If that input is exhausted, then
sl@0: in() will be called. Therefore strm->next_in must be initialized before
sl@0: calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
sl@0: immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
sl@0: must also be initialized, and then if strm->avail_in is not zero, input will
sl@0: initially be taken from strm->next_in[0 .. strm->avail_in - 1].
sl@0:
sl@0: The in_desc and out_desc parameters of inflateBack() is passed as the
sl@0: first parameter of in() and out() respectively when they are called. These
sl@0: descriptors can be optionally used to pass any information that the caller-
sl@0: supplied in() and out() functions need to do their job.
sl@0:
sl@0: On return, inflateBack() will set strm->next_in and strm->avail_in to
sl@0: pass back any unused input that was provided by the last in() call. The
sl@0: return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
sl@0: if in() or out() returned an error, Z_DATA_ERROR if there was a format
sl@0: error in the deflate stream (in which case strm->msg is set to indicate the
sl@0: nature of the error), or Z_STREAM_ERROR if the stream was not properly
sl@0: initialized. In the case of Z_BUF_ERROR, an input or output error can be
sl@0: distinguished using strm->next_in which will be Z_NULL only if in() returned
sl@0: an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to
sl@0: out() returning non-zero. (in() will always be called before out(), so
sl@0: strm->next_in is assured to be defined if out() returns non-zero.) Note
sl@0: that inflateBack() cannot return Z_OK.
sl@0:
sl@0: @param strm stream of data
sl@0: @param in input function pointer
sl@0: @param in_desc input parameters for in_func
sl@0: @param out output function pointer
sl@0: @param out_desc output parameters for out_func
sl@0: @return Refer to the above description for detailed explanation
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
sl@0: in_func in, void FAR *in_desc,
sl@0: out_func out, void FAR *out_desc));
sl@0:
sl@0: /**
sl@0: All memory allocated by inflateBackInit() is freed.
sl@0:
sl@0: @param strm stream of data
sl@0: @return inflateBackEnd returns Z_OK on success, or Z_STREAM_ERROR if the stream
sl@0: state was inconsistent.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
sl@0:
sl@0: /**
sl@0: Return flags indicating compile-time options.
sl@0:
sl@0: Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
sl@0: 1.0: size of uInt
sl@0: 3.2: size of uLong
sl@0: 5.4: size of voidpf (pointer)
sl@0: 7.6: size of z_off_t
sl@0:
sl@0: Compiler, assembler, and debug options:
sl@0: 8: DEBUG
sl@0: 9: ASMV or ASMINF -- use ASM code
sl@0: 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
sl@0: 11: 0 (reserved)
sl@0:
sl@0: One-time table building (smaller code, but not thread-safe if true):
sl@0: 12: BUILDFIXED -- build static block decoding tables when needed
sl@0: 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
sl@0: 14,15: 0 (reserved)
sl@0:
sl@0: Library content (indicates missing functionality):
sl@0: 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
sl@0: deflate code when not needed)
sl@0: 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
sl@0: and decode gzip streams (to avoid linking crc code)
sl@0: 18-19: 0 (reserved)
sl@0:
sl@0: Operation variations (changes in library functionality):
sl@0: 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
sl@0: 21: FASTEST -- deflate algorithm with only one, lowest compression level
sl@0: 22,23: 0 (reserved)
sl@0:
sl@0: The sprintf variant used by gzprintf (zero is best):
sl@0: 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
sl@0: 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
sl@0: 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
sl@0:
sl@0: Remainder:
sl@0: 27-31: 0 (reserved)
sl@0:
sl@0: @return Refer to the above description for detailed explanation
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
sl@0:
sl@0: /* utility functions */
sl@0:
sl@0: /*
sl@0: The following utility functions are implemented on top of the
sl@0: basic stream-oriented functions. To simplify the interface, some
sl@0: default options are assumed (compression level and memory usage,
sl@0: standard memory allocation functions). The source code of these
sl@0: utility functions can easily be modified if you need special options.
sl@0: */
sl@0:
sl@0: /**
sl@0: Compresses the source buffer into the destination buffer. sourceLen is
sl@0: the byte length of the source buffer. Upon entry, destLen is the total
sl@0: size of the destination buffer, which must be at least the value returned
sl@0: by compressBound(sourceLen). Upon exit, destLen is the actual size of the
sl@0: compressed buffer.
sl@0: This function can be used to compress a whole file at once if the
sl@0: input file is mmap'ed.
sl@0:
sl@0: @param dest destination buffer
sl@0: @param destLen byte length of destination buffer
sl@0: @param source source buffer
sl@0: @param sourceLen byte length of source buffer
sl@0: @return compress returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_BUF_ERROR if there was not enough room in the output
sl@0: buffer.
sl@0: */
sl@0: ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen,
sl@0: const Bytef *source, uLong sourceLen));
sl@0:
sl@0: /**
sl@0: Compresses the source buffer into the destination buffer. The level
sl@0: parameter has the same meaning as in deflateInit. sourceLen is the byte
sl@0: length of the source buffer. Upon entry, destLen is the total size of the
sl@0: destination buffer, which must be at least the value returned by
sl@0: compressBound(sourceLen). Upon exit, destLen is the actual size of the
sl@0: compressed buffer.
sl@0:
sl@0: @param dest destination buffer
sl@0: @param destLen byte length of destination buffer
sl@0: @param source source buffer
sl@0: @param sourceLen byte length of source buffer
sl@0: @param level Compression level
sl@0: @return compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_BUF_ERROR if there was not enough room in the output buffer,
sl@0: Z_STREAM_ERROR if the level parameter is invalid.
sl@0: */
sl@0: ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen,
sl@0: const Bytef *source, uLong sourceLen,
sl@0: int level));
sl@0:
sl@0: /**
sl@0: compressBound() returns an upper bound on the compressed size after
sl@0: compress() or compress2() on sourceLen bytes. It would be used before
sl@0: a compress() or compress2() call to allocate the destination buffer.
sl@0:
sl@0: @param source buffer length
sl@0: @return compressBound returns an upper bound on the compressed size after
sl@0: compress() or compress2() on sourceLen bytes.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
sl@0:
sl@0: /**
sl@0: Decompresses the source buffer into the destination buffer. sourceLen is
sl@0: the byte length of the source buffer. Upon entry, destLen is the total
sl@0: size of the destination buffer, which must be large enough to hold the
sl@0: entire uncompressed data. (The size of the uncompressed data must have
sl@0: been saved previously by the compressor and transmitted to the decompressor
sl@0: by some mechanism outside the scope of this compression library.)
sl@0: Upon exit, destLen is the actual size of the compressed buffer.
sl@0: This function can be used to decompress a whole file at once if the
sl@0: input file is mmap'ed.
sl@0:
sl@0: @param dest destination buffer
sl@0: @param destLen byte length of destination buffer
sl@0: @param source source buffer
sl@0: @param sourceLen byte length of source buffer
sl@0: @return uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_BUF_ERROR if there was not enough room in the output
sl@0: buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.
sl@0: */
sl@0: ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
sl@0: const Bytef *source, uLong sourceLen));
sl@0:
sl@0: #ifndef SYMBIAN_EZLIB_EXCLUDE_GZ_FUNCTIONS
sl@0: /** gzfile is typedef to voidp i.e. void pointer(void*) */
sl@0: typedef voidp gzFile;
sl@0:
sl@0: /**
sl@0: Opens a gzip (.gz) file for reading or writing. The mode parameter
sl@0: is as in fopen ("rb" or "wb") but can also include a compression level
sl@0: ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
sl@0: Huffman only compression as in "wb1h", or 'R' for run-length encoding
sl@0: as in "wb1R". (See the description of deflateInit2 for more information
sl@0: about the strategy parameter.)
sl@0:
sl@0: gzopen can be used to read a file which is not in gzip format; in this
sl@0: case gzread will directly read from the file without decompression.
sl@0:
sl@0: @param path location of the file
sl@0: @param mode refer to above description
sl@0: @return gzopen returns NULL if the file could not be opened or if there was
sl@0: insufficient memory to allocate the (de)compression state; errno
sl@0: can be checked to distinguish the two cases (if errno is zero, the
sl@0: zlib error is Z_MEM_ERROR).
sl@0: */
sl@0: ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));
sl@0:
sl@0: /**
sl@0: gzdopen() associates a gzFile with the file descriptor fd. File
sl@0: descriptors are obtained from calls like open, dup, creat, pipe or
sl@0: fileno (in the file has been previously opened with fopen).
sl@0: The mode parameter is as in gzopen.
sl@0: The next call of gzclose on the returned gzFile will also close the
sl@0: file descriptor fd, just like fclose(fdopen(fd), mode) closes the file
sl@0: descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode).
sl@0:
sl@0: @param fd file descriptor
sl@0: @param mode The mode parameter is as in gzopen
sl@0: @return gzdopen returns NULL if there was insufficient memory to allocate
sl@0: the (de)compression state.
sl@0: */
sl@0: ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
sl@0:
sl@0: /**
sl@0: Dynamically update the compression level or strategy. See the description
sl@0: of deflateInit2 for the meaning of these parameters.
sl@0:
sl@0: @param file gzip file
sl@0: @param level compression level
sl@0: @param strategy compression algorithm
sl@0: @return gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not
sl@0: opened for writing.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
sl@0:
sl@0: /**
sl@0: Reads the given number of uncompressed bytes from the compressed file.
sl@0: If the input file was not in gzip format, gzread copies the given number
sl@0: of bytes into the buffer.
sl@0:
sl@0: @param file gzip file
sl@0: @param buf buffer to store the copied data from the gzip file
sl@0: @param len length of the data to be copied
sl@0: @return gzread returns the number of uncompressed bytes actually read (0 for
sl@0: end of file, -1 for error).
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
sl@0:
sl@0: /**
sl@0: Writes the given number of uncompressed bytes into the compressed file.
sl@0: gzwrite returns the number of uncompressed bytes actually written
sl@0: (0 in case of error).
sl@0:
sl@0: @param file gzip file
sl@0: @param buf buffer containing data to be written to the gzip file
sl@0: @param len length of the data
sl@0: @return gzwrite returns the number of uncompressed bytes actually written
sl@0: (0 in case of error)
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
sl@0: voidpc buf, unsigned len));
sl@0:
sl@0: /**
sl@0: Converts, formats, and writes the args to the compressed file under
sl@0: control of the format string, as in fprintf. gzprintf returns the number of
sl@0: uncompressed bytes actually written (0 in case of error). The number of
sl@0: uncompressed bytes written is limited to 4095. The caller should assure that
sl@0: this limit is not exceeded. If it is exceeded, then gzprintf() will return
sl@0: return an error (0) with nothing written. In this case, there may also be a
sl@0: buffer overflow with unpredictable consequences, which is possible only if
sl@0: zlib was compiled with the insecure functions sprintf() or vsprintf()
sl@0: because the secure snprintf() or vsnprintf() functions were not available.
sl@0:
sl@0: @param file gzip file
sl@0: @param format format string
sl@0: @return refer to the description above
sl@0: */
sl@0: ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));
sl@0:
sl@0: /**
sl@0: Writes the given null-terminated string to the compressed file, excluding
sl@0: the terminating null character.
sl@0:
sl@0: @param file gzip file
sl@0: @param s null-terminated string
sl@0: @return gzputs returns the number of characters written, or -1 in case of error.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
sl@0:
sl@0: /**
sl@0: Reads bytes from the compressed file until len-1 characters are read, or
sl@0: a newline character is read and transferred to buf, or an end-of-file
sl@0: condition is encountered. The string is then terminated with a null
sl@0: character.
sl@0:
sl@0: @param file gzip file
sl@0: @param buf buffer to store the copied data from the gzip file
sl@0: @param len number of characters to be read (len-1)
sl@0: @return gzgets returns buf, or Z_NULL in case of error.
sl@0: */
sl@0: ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
sl@0:
sl@0: /**
sl@0: Writes c, converted to an unsigned char, into the compressed file.
sl@0: gzputc returns the value that was written, or -1 in case of error.
sl@0:
sl@0: @param file gzip file
sl@0: @param c character
sl@0: @return gzputc returns the value that was written, or -1 in case of error.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
sl@0:
sl@0: /**
sl@0: Reads one byte from the compressed file. gzgetc returns this byte
sl@0: or -1 in case of end of file or error.
sl@0:
sl@0: @param file gzip file
sl@0: @return gzgetc returns this byte or -1 in case of end of file or error.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Push one character back onto the stream to be read again later.
sl@0: Only one character of push-back is allowed. gzungetc() returns the
sl@0: character pushed, or -1 on failure. gzungetc() will fail if a
sl@0: character has been pushed but not read yet, or if c is -1. The pushed
sl@0: character will be discarded if the stream is repositioned with gzseek()
sl@0: or gzrewind().
sl@0:
sl@0: @param c character
sl@0: @param file gzip file
sl@0: @return gzungetc returns the character pushed, or -1 on failure.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
sl@0:
sl@0: /**
sl@0: Flushes all pending output into the compressed file. The parameter
sl@0: flush is as in the deflate() function. The return value is the zlib
sl@0: error number (see function gzerror below). gzflush returns Z_OK if
sl@0: the flush parameter is Z_FINISH and all output could be flushed.
sl@0: gzflush should be called only when strictly necessary because it can
sl@0: degrade compression.
sl@0:
sl@0: @param file gzip file
sl@0: @param flush parameter flush is as in the deflate() function
sl@0: @return gzflush returns Z_OK if the flush parameter is Z_FINISH and all output could be flushed.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
sl@0:
sl@0: /**
sl@0: Sets the starting position for the next gzread or gzwrite on the
sl@0: given compressed file. The offset represents a number of bytes in the
sl@0: uncompressed data stream. The whence parameter is defined as in lseek(2);
sl@0: the value SEEK_END is not supported.
sl@0: If the file is opened for reading, this function is emulated but can be
sl@0: extremely slow. If the file is opened for writing, only forward seeks are
sl@0: supported; gzseek then compresses a sequence of zeroes up to the new
sl@0: starting position.
sl@0:
sl@0: @param file gzip file
sl@0: @param offset represents a number of bytes in the uncompressed data stream
sl@0: @param whence defined as in lseek(2); the value SEEK_END is not supported.
sl@0: @return gzseek returns the resulting offset location as measured in bytes from
sl@0: the beginning of the uncompressed stream, or -1 in case of error, in
sl@0: particular if the file is opened for writing and the new starting position
sl@0: would be before the current position.
sl@0: */
sl@0: ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
sl@0: z_off_t offset, int whence));
sl@0:
sl@0: /**
sl@0: Rewinds the given file. This function is supported only for reading.
sl@0:
sl@0: gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
sl@0:
sl@0: @param file gzip file
sl@0: @return refer to gzseek() return value & description
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Returns the starting position for the next gzread or gzwrite on the
sl@0: given compressed file. This position represents a number of bytes in the
sl@0: uncompressed data stream.
sl@0:
sl@0: gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
sl@0:
sl@0: @param file gzip file
sl@0: @return gztell returns the starting position for the next gzread or gzwrite on the
sl@0: given compressed file
sl@0: */
sl@0: ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Returns 1 when EOF has previously been detected reading the given
sl@0: input stream, otherwise zero.
sl@0:
sl@0: @param file gzip file
sl@0: @return gzeof returns 1 when EOF has previously been detected reading the given
sl@0: input stream, otherwise zero.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzeof OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Returns 1 if file is being read directly without decompression, otherwise
sl@0: zero.
sl@0:
sl@0: @param file gzip file
sl@0: @return gzdirect returns 1 if file is being read directly without decompression, otherwise zero.
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Flushes all pending output if necessary, closes the compressed file
sl@0: and deallocates all the (de)compression state. The return value is the zlib
sl@0: error number (see function gzerror below).
sl@0:
sl@0: @param file gzip file
sl@0: @return gzclose returns the zlib error number (see function gzerror below).
sl@0: */
sl@0: ZEXTERN int ZEXPORT gzclose OF((gzFile file));
sl@0:
sl@0: /**
sl@0: Returns the error message for the last error which occurred on the
sl@0: given compressed file. errnum is set to zlib error number. If an
sl@0: error occurred in the file system and not in the compression library,
sl@0: errnum is set to Z_ERRNO and the application may consult errno
sl@0: to get the exact error code.
sl@0:
sl@0: @param file gzip file
sl@0: @param errnum error number
sl@0: @return gzerror returns the error message for the last error which occurred on the
sl@0: given compressed file.
sl@0: */
sl@0: ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
sl@0:
sl@0: /**
sl@0: Clears the error and end-of-file flags for file. This is analogous to the
sl@0: clearerr() function in stdio. This is useful for continuing to read a gzip
sl@0: file that is being written concurrently.
sl@0:
sl@0: @param file gzip file
sl@0: */
sl@0: ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
sl@0:
sl@0: #endif //SYMBIAN_EZLIB_EXCLUDE_GZ_FUNCTIONS
sl@0:
sl@0: /* checksum functions */
sl@0:
sl@0: /*
sl@0: These functions are not related to compression but are exported
sl@0: anyway because they might be useful in applications using the
sl@0: compression library.
sl@0: */
sl@0:
sl@0: /**
sl@0: Update a running Adler-32 checksum with the bytes buf[0..len-1] and
sl@0: return the updated checksum. If buf is NULL, this function returns
sl@0: the required initial value for the checksum.
sl@0: An Adler-32 checksum is almost as reliable as a CRC32 but can be computed
sl@0: much faster. Usage example:
sl@0:
sl@0: uLong adler = adler32(0L, Z_NULL, 0);
sl@0:
sl@0: while (read_buffer(buffer, length) != EOF) {
sl@0: adler = adler32(adler, buffer, length);
sl@0: }
sl@0: if (adler != original_adler) error();
sl@0:
sl@0: @param adler Adler-32 checksum
sl@0: @param buf pointer to buffer
sl@0: @param len length of buffer
sl@0: @return If buf is NULL, this function returns
sl@0: the required initial value for the checksum.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
sl@0:
sl@0: /**
sl@0: Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
sl@0: and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
sl@0: each, adler1 and adler2.
sl@0:
sl@0: @param adler1 Adler-32 checksum
sl@0: @param adler2 Adler-32 checksum
sl@0: @param len2 length
sl@0: @return adler32_combine returns the Adler-32 checksum of
sl@0: seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
sl@0: z_off_t len2));
sl@0:
sl@0: /**
sl@0: Update a running CRC-32 with the bytes buf[0..len-1] and return the
sl@0: updated CRC-32. If buf is NULL, this function returns the required initial
sl@0: value for the for the crc. Pre- and post-conditioning (one's complement) is
sl@0: performed within this function so it shouldn't be done by the application.
sl@0: Usage example:
sl@0:
sl@0: uLong crc = crc32(0L, Z_NULL, 0);
sl@0:
sl@0: while (read_buffer(buffer, length) != EOF) {
sl@0: crc = crc32(crc, buffer, length);
sl@0: }
sl@0: if (crc != original_crc) error();
sl@0:
sl@0: @param crc CRC-32 check value
sl@0: @param buf pointer to buffer
sl@0: @param len length of buffer
sl@0: @return If buf is NULL, this function returns the required initial
sl@0: value for the for the crc.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
sl@0:
sl@0: /**
sl@0: Combine two CRC-32 check values into one. For two sequences of bytes,
sl@0: seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
sl@0: calculated for each, crc1 and crc2.
sl@0:
sl@0: @param crc1 CRC-32 check value
sl@0: @param crc2 CRC-32 check value
sl@0: @param len2 length
sl@0: @return crc32_combine returns the CRC-32 check value of seq1 and seq2
sl@0: concatenated, requiring only crc1, crc2, and len2.
sl@0: */
sl@0: ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));
sl@0:
sl@0:
sl@0:
sl@0: /* various hacks, don't look :) */
sl@0:
sl@0: /* deflateInit and inflateInit are macros to allow checking the zlib version
sl@0: * and the compiler's view of z_stream:
sl@0: */
sl@0: /**
sl@0: Initializes the internal stream state for compression. The fields
sl@0: zalloc, zfree and opaque must be initialized before by the caller.
sl@0: If zalloc and zfree are set to Z_NULL, deflateInit updates them to
sl@0: use default allocation functions.
sl@0:
sl@0: The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
sl@0: 1 gives best speed, 9 gives best compression, 0 gives no compression at
sl@0: all (the input data is simply copied a block at a time).
sl@0: Z_DEFAULT_COMPRESSION requests a default compromise between speed and
sl@0: compression (currently equivalent to level 6).
sl@0:
sl@0: deflateInit does not perform any compression: this will be done by deflate().
sl@0:
sl@0: @param strm stream of data
sl@0: @param level compression level
sl@0: @param version version of library
sl@0: @param stream_size stream size
sl@0: @return deflateInit_ returns Z_OK if success, Z_MEM_ERROR if there was not
sl@0: enough memory, Z_STREAM_ERROR if level is not a valid compression level,
sl@0: Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
sl@0: with the version assumed by the caller (ZLIB_VERSION).
sl@0: msg is set to null if there is no error message.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
sl@0: const char *version, int stream_size));
sl@0:
sl@0: /**
sl@0: Initializes the internal stream state for decompression. The fields
sl@0: next_in, avail_in, zalloc, zfree and opaque must be initialized before by
sl@0: the caller. If next_in is not Z_NULL and avail_in is large enough (the exact
sl@0: value depends on the compression method), inflateInit determines the
sl@0: compression method from the zlib header and allocates all data structures
sl@0: accordingly; otherwise the allocation will be deferred to the first call of
sl@0: inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to
sl@0: use default allocation functions.
sl@0:
sl@0: inflateInit does not perform any decompression apart from reading
sl@0: the zlib header if present: this will be done by inflate(). (So next_in and
sl@0: avail_in may be modified, but next_out and avail_out are unchanged.)
sl@0:
sl@0: @param strm stream of data
sl@0: @param version version of library
sl@0: @param stream_size stream size
sl@0: @return inflateInit_ returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
sl@0: version assumed by the caller. msg is set to null if there is no error
sl@0: message.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
sl@0: const char *version, int stream_size));
sl@0:
sl@0: /**
sl@0: This is another version of deflateInit with more compression options. The
sl@0: fields next_in, zalloc, zfree and opaque must be initialized before by
sl@0: the caller.
sl@0:
sl@0: The method parameter is the compression method. It must be Z_DEFLATED in
sl@0: this version of the library.
sl@0:
sl@0: The windowBits parameter is the base two logarithm of the window size
sl@0: (the size of the history buffer). It should be in the range 8..15 for this
sl@0: version of the library. Larger values of this parameter result in better
sl@0: compression at the expense of memory usage. The default value is 15 if
sl@0: deflateInit is used instead.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
sl@0: determines the window size. deflate() will then generate raw deflate data
sl@0: with no zlib header or trailer, and will not compute an adler32 check value.
sl@0:
sl@0: windowBits can also be greater than 15 for optional gzip encoding. Add
sl@0: 16 to windowBits to write a simple gzip header and trailer around the
sl@0: compressed data instead of a zlib wrapper. The gzip header will have no
sl@0: file name, no extra data, no comment, no modification time (set to zero),
sl@0: no header crc, and the operating system will be set to 3 (UNIX). If a
sl@0: gzip stream is being written, strm->adler is a crc32 instead of an adler32.
sl@0:
sl@0: The memLevel parameter specifies how much memory should be allocated
sl@0: for the internal compression state. memLevel=1 uses minimum memory but
sl@0: is slow and reduces compression ratio; memLevel=9 uses maximum memory
sl@0: for optimal speed. The default value is 8. See zconf.h for total memory
sl@0: usage as a function of windowBits and memLevel.
sl@0:
sl@0: The strategy parameter is used to tune the compression algorithm. Use the
sl@0: value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
sl@0: filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
sl@0: string match), or Z_RLE to limit match distances to one (run-length
sl@0: encoding). Filtered data consists mostly of small values with a somewhat
sl@0: random distribution. In this case, the compression algorithm is tuned to
sl@0: compress them better. The effect of Z_FILTERED is to force more Huffman
sl@0: coding and less string matching; it is somewhat intermediate between
sl@0: Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as
sl@0: Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy
sl@0: parameter only affects the compression ratio but not the correctness of the
sl@0: compressed output even if it is not set appropriately. Z_FIXED prevents the
sl@0: use of dynamic Huffman codes, allowing for a simpler decoder for special
sl@0: applications.
sl@0: deflateInit2 does not perform any compression: this will be done by deflate().
sl@0:
sl@0: @param strm stream of data
sl@0: @param level compression level
sl@0: @param method compression method
sl@0: @param windowBits refer to above note & description for window bits value
sl@0: @param memLevel memory level (i.e. how much memory should be allocated). refer to above description for more detail
sl@0: @param strategy compression algorithm
sl@0: @param version version of library
sl@0: @param stream_size size of stream
sl@0: @return deflateInit2_ returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid
sl@0: method). msg is set to null if there is no error message.
sl@0: */
sl@0: ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
sl@0: int windowBits, int memLevel,
sl@0: int strategy, const char *version,
sl@0: int stream_size));
sl@0:
sl@0: /**
sl@0: This is another version of inflateInit with an extra parameter. The
sl@0: fields next_in, avail_in, zalloc, zfree and opaque must be initialized
sl@0: before by the caller.
sl@0:
sl@0: The windowBits parameter is the base two logarithm of the maximum window
sl@0: size (the size of the history buffer). It should be in the range 8..15 for
sl@0: this version of the library. The default value is 15 if inflateInit is used
sl@0: instead. windowBits must be greater than or equal to the windowBits value
sl@0: provided to deflateInit2() while compressing, or it must be equal to 15 if
sl@0: deflateInit2() was not used. If a compressed stream with a larger window
sl@0: size is given as input, inflate() will return with the error code
sl@0: Z_DATA_ERROR instead of trying to allocate a larger window.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
sl@0: determines the window size. inflate() will then process raw deflate data,
sl@0: not looking for a zlib or gzip header, not generating a check value, and not
sl@0: looking for any check values for comparison at the end of the stream. This
sl@0: is for use with other formats that use the deflate compressed data format
sl@0: such as zip. Those formats provide their own check values. If a custom
sl@0: format is developed using the raw deflate format for compressed data, it is
sl@0: recommended that a check value such as an adler32 or a crc32 be applied to
sl@0: the uncompressed data as is done in the zlib, gzip, and zip formats. For
sl@0: most applications, the zlib format should be used as is. Note that comments
sl@0: above on the use in deflateInit2() applies to the magnitude of windowBits.
sl@0:
sl@0: windowBits can also be greater than 15 for optional gzip decoding. Add
sl@0: 32 to windowBits to enable zlib and gzip decoding with automatic header
sl@0: detection, or add 16 to decode only the gzip format (the zlib format will
sl@0: return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
sl@0: a crc32 instead of an adler32.
sl@0:
sl@0: @param strm stream of data
sl@0: @param windowBits refer to above note & description for window bits value
sl@0: @param version version of library
sl@0: @param stream_size size of stream
sl@0: @return inflateInit2_ returns Z_OK if success, Z_MEM_ERROR if there was not enough
sl@0: memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
sl@0: is set to null if there is no error message. inflateInit2 does not perform
sl@0: any decompression apart from reading the zlib header if present: this will
sl@0: be done by inflate(). (So next_in and avail_in may be modified, but next_out
sl@0: and avail_out are unchanged.)
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
sl@0: const char *version, int stream_size));
sl@0:
sl@0: /**
sl@0: Initialize the internal stream state for decompression using inflateBack()
sl@0: calls. The fields zalloc, zfree and opaque in strm must be initialized
sl@0: before the call. If zalloc and zfree are Z_NULL, then the default library-
sl@0: derived memory allocation routines are used. windowBits is the base two
sl@0: logarithm of the window size, in the range 8..15. window is a caller
sl@0: supplied buffer of that size. Except for special applications where it is
sl@0: assured that deflate was used with small window sizes, windowBits must be 15
sl@0: and a 32K byte window must be supplied to be able to decompress general
sl@0: deflate streams.
sl@0:
sl@0: Note: In this version of the library a windowBits value of 8 is unsupported
sl@0: due to a problem with the window size being set to 256 bytes. Although a
sl@0: value of 8 will be accepted by deflateInit2(), as it is being changed
sl@0: internally from 8 to 9, it will not be possible to use the same value when it
sl@0: comes to decompression. This is because inflateInit2() does not make the same
sl@0: change internally and as a result a Z_DATA_ERROR is returned when calling
sl@0: inflate(). It is therefore advised that for this version of the library
sl@0: windowBits of 9 is used in place of 8.
sl@0:
sl@0: See inflateBack() for the usage of these routines.
sl@0:
sl@0: @param strm stream of data
sl@0: @param windowBits refer to above note for window bits value
sl@0: @param window window is a caller supplied buffer of that size
sl@0: @param version version of library
sl@0: @param stream_size size of stream
sl@0: @return inflateBackInit_ returns Z_OK on success, Z_STREAM_ERROR if any of
sl@0: the paramaters are invalid, Z_MEM_ERROR if the internal state could not
sl@0: be allocated, or Z_VERSION_ERROR if the version of the library does not
sl@0: match the version of the header file.
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
sl@0: unsigned char FAR *window,
sl@0: const char *version,
sl@0: int stream_size));
sl@0:
sl@0: /**
sl@0: Macro deflateInit defined for deflateInit_()
sl@0: @param strm stream of data
sl@0: @param level compression level
sl@0: */
sl@0: #define deflateInit(strm, level) \
sl@0: deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
sl@0: /**
sl@0: Macro inflateInit defined for inflateInit_()
sl@0: @param strm stream of data
sl@0: */
sl@0: #define inflateInit(strm) \
sl@0: inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
sl@0: /**
sl@0: Macro deflateInit2 defined for deflateInit2_()
sl@0: @param strm stream of data
sl@0: @param level compression level
sl@0: @param method compression method
sl@0: @param windowBits refer to the note for window bits value in deflateInit2_()
sl@0: @param memLevel memory level (i.e. how much memory should be allocated). refer to above description for more detail
sl@0: @param strategy compression algorithm
sl@0: */
sl@0: #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
sl@0: deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
sl@0: (strategy), ZLIB_VERSION, sizeof(z_stream))
sl@0: /**
sl@0: Macro inflateInit2 defined for inflateInit2_()
sl@0: @param strm stream of data
sl@0: @param windowBits refer to the note for window bits value in inflateInit2_()
sl@0: */
sl@0: #define inflateInit2(strm, windowBits) \
sl@0: inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
sl@0: /**
sl@0: Macro inflateBackInit defined for inflateBackInit_()
sl@0: @param strm stream of data
sl@0: @param windowBits refer to the note for window bits value in inflateBackInit_()
sl@0: @param window window is a caller supplied buffer of that size
sl@0: */
sl@0: #define inflateBackInit(strm, windowBits, window) \
sl@0: inflateBackInit_((strm), (windowBits), (window), \
sl@0: ZLIB_VERSION, sizeof(z_stream))
sl@0:
sl@0:
sl@0: #if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)
sl@0: /** Hack for buggy compilers */
sl@0: struct internal_state {int dummy;};
sl@0: #endif
sl@0:
sl@0: /**
sl@0: Returns the string representing the error code
sl@0:
sl@0: @param int error code
sl@0: @return zError returns string representing the error code
sl@0: */
sl@0: ZEXTERN const char * ZEXPORT zError OF((int));
sl@0: /**
sl@0: Checks whether inflate is currently at the end of a block generated by Z_SYNC_FLUSH or Z_FULL_FLUSH
sl@0:
sl@0: @param z stream of data
sl@0: @return inflateSyncPoint returns true(1) if inflate is currently at the end of a block. Otherwise false(0)
sl@0: */
sl@0: ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));
sl@0: /**
sl@0: Initialize the tables before allowing more than one thread to use crc32()
sl@0:
sl@0: @return get_crc_table returns pointer to the crc table after initialisation
sl@0: */
sl@0: ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));
sl@0:
sl@0: #ifdef __cplusplus
sl@0: }
sl@0: #endif
sl@0:
sl@0: #endif /* _ZLIB_H */