Lines Matching +full:zlib +full:- +full:level
3 /* zlib.h -- interface of the 'zlib-ng' compression library
4 Forked from and compatible with zlib 1.2.11
6 Copyright (C) 1995-2016 Jean-loup Gailly and Mark Adler
8 This software is provided 'as-is', without any express or implied
24 Jean-loup Gailly Mark Adler
28 The data format used by the zlib library is described by RFCs (Request for
30 (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
34 # error Include zlib-ng.h for zlib-ng API or zlib.h for zlib-compat API but not both
56 #define ZLIB_VERSION "1.2.11.zlib-ng"
64 The 'zlib' compression library provides in-memory compression and
75 The compressed data format used by default by the in-memory functions is
76 the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
81 with "gz". The gzip format is different from the zlib format. gzip is a
87 The zlib format was designed to be compact and fast for use in memory
88 and on communications channels. The gzip format was designed for single-
89 file compression on file systems, has a larger header than zlib to maintain
90 directory information, and uses a different, slower check method than zlib.
120 unsigned long adler; /* Adler-32 or CRC-32 value of the uncompressed data */
127 gzip header information passed to and from zlib routines. See RFC 1952
138 unsigned char *name; /* pointer to zero-terminated file name or NULL */
140 unsigned char *comment; /* pointer to zero-terminated comment or NULL */
161 If zlib is used in a multi-threaded application, zalloc and zfree must be
162 thread safe. In that case, zlib is thread-safe. When zalloc and zfree are
186 #define Z_ERRNO (-1)
187 #define Z_STREAM_ERROR (-2)
188 #define Z_DATA_ERROR (-3)
189 #define Z_MEM_ERROR (-4)
190 #define Z_BUF_ERROR (-5)
191 #define Z_VERSION_ERROR (-6)
199 #define Z_DEFAULT_COMPRESSION (-1)
218 #define Z_NULL NULL /* for compatibility with zlib, was for initializing zalloc, zfree, opaque */
229 compatible with the zlib.h header file used by the application. This check
234 Z_EXTERN int Z_EXPORT deflateInit (z_stream *strm, int level);
241 The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
245 equivalent to level 6).
248 memory, Z_STREAM_ERROR if level is not a valid compression level, or
249 Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
266 - Compress more input starting at next_in and update next_in and avail_in
271 - Generate more output starting at next_out and update next_out and avail_out
327 avail_out), until the flush is complete (deflate returns with non-zero
347 deflate() sets strm->adler to the Adler-32 checksum of all input read
349 strm->adler will be the CRC-32 checksum of the input read so far. (See
352 deflate() may update strm->data_type if it can make a good guess about
395 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
401 implementation of inflateInit() does not process any header information --
416 - Decompress more input starting at next_in and update next_in and avail_in
422 - Generate more output starting at next_out and update next_out and avail_out
442 the zlib or gzip format, this will cause inflate() to return immediately
448 To assist in this, on return inflate() always sets strm->data_type to the
449 number of unused bits in the last byte taken from strm->next_in, plus 64 if
451 128 if inflate() returned immediately after decoding an end-of-block code or
453 stream. The end-of-block will not be indicated until all of the uncompressed
454 data from that block has been written to strm->next_out. The number of
465 256 is added to the value of strm->data_type when inflate() returns
492 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
494 strm->adler to the Adler-32 checksum of all output produced so far (that is,
496 below. At the end of the stream, inflate() checks that its computed Adler-32
500 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
504 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
505 produced so far. The CRC-32 is checked against the gzip trailer, as is the
512 corrupted (input stream not conforming to the zlib format or incorrect check
513 value, in which case strm->msg points to a string with a more specific
545 int level,
565 will result in 9 (a 512-byte window). In that case, providing 8 to
566 inflateInit2() will result in an error when the zlib header with 9 is
571 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
573 with no zlib header or trailer, and will not compute a check value.
577 compressed data instead of a zlib wrapper. The gzip header will have no
581 being written, strm->adler is a CRC-32 instead of an Adler-32.
583 For raw deflate or gzip encoding, a request for a 256-byte window is
584 rejected as invalid, since only the zlib header provides a means of
596 string match), or Z_RLE to limit match distances to one (run-length
610 method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
621 without producing any compressed output. When using the zlib format, this
646 Upon return of this function, strm->adler is set to the Adler-32 value
648 which dictionary has been used by the compressor. (The Adler-32 value
651 Adler-32 value is not computed and strm->adler is not set.
671 to 258 bytes less in that case, due to how zlib's implementation of deflate
673 up to 258 bytes long. If the application needs the last window-size bytes of
674 input, then that would need to be saved by the application outside of zlib.
685 tried, for example when there are several ways of pre-processing the input
701 will leave the compression level and any other attributes that may have been
708 Z_EXTERN int Z_EXPORT deflateParams(z_stream *strm, int level, int strategy);
710 Dynamically update the compression level and compression strategy. The
711 interpretation of level and strategy is as in deflateInit2(). This can be
714 If the compression approach (which is a function of the level) or the
717 compressed with the old level and strategy using deflate(strm, Z_BLOCK).
719 respectively. The new level and strategy will take effect at the next call
731 If this is done, the old level and strategy will be applied to the data
732 compressed before deflateParams(), and the new level and strategy will be
747 used by someone who understands the algorithm used by zlib's deflate for
806 ignored -- the extra flags are set according to the compression level). The
810 the current versions of the command-line version of gzip (up through version
811 1.3.x) do not support header crc's, and will report that it is a "multi-part
839 the zlib header of the compressed stream.
841 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
843 not looking for a zlib or gzip header, not generating a check value, and not
848 recommended that a check value such as an Adler-32 or a CRC-32 be applied to
849 the uncompressed data as is done in the zlib, gzip, and zip formats. For
850 most applications, the zlib format should be used as is. Note that comments
854 32 to windowBits to enable zlib and gzip decoding with automatic header
855 detection, or add 16 to decode only the gzip format (the zlib format will
856 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
857 CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see
865 memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
869 apart from possibly reading the zlib header if present: actual decompression
872 of inflateInit2() does not process any header information -- that is
881 can be determined from the Adler-32 value returned by that call of inflate.
892 expected one (incorrect Adler-32 value). inflateSetDictionary does not
990 return value down 16 bits. If the upper value is -1 and the lower value is
992 If the upper value is -1 and the lower value is non-zero, then inflate is in
994 bytes from the input remaining to copy. If the upper value is not -1, then
1010 inflateMark returns the value noted above, or -65536 if the provided
1019 As inflate() processes the gzip stream, head->done is zero until the header
1020 is completed, at which time head->done is set to one. If a zlib stream is
1021 being decoded, then head->done is set to -1 to indicate that there will be
1058 before the call. If zalloc and zfree are NULL, then the default library-
1079 inflateBack() does a raw inflate with a single call using a call-back
1088 and to initialize the state with the user-provided window buffer.
1093 A raw deflate stream is one with no zlib or gzip header or trailer.
1098 behavior of inflate(), which expects a zlib header and trailer around the
1108 there is no input available, in() must return zero -- buf is ignored in that
1109 case -- and inflateBack() will return a buffer error. inflateBack() will
1110 call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
1111 out() should return zero on success, or non-zero on failure. If out()
1112 returns non-zero, inflateBack() will return with an error. Neither in() nor
1115 The length written by out() will be at most the window size. Any non-zero
1119 setting strm->next_in and strm->avail_in. If that input is exhausted, then
1120 in() will be called. Therefore strm->next_in must be initialized before
1121 calling inflateBack(). If strm->next_in is NULL, then in() will be called
1122 immediately for input. If strm->next_in is not NULL, then strm->avail_in
1123 must also be initialized, and then if strm->avail_in is not zero, input will
1124 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1128 descriptors can be optionally used to pass any information that the caller-
1131 On return, inflateBack() will set strm->next_in and strm->avail_in to
1135 in the deflate stream (in which case strm->msg is set to indicate the nature
1138 using strm->next_in which will be NULL only if in() returned an error. If
1139 strm->next_in is not NULL, then the Z_BUF_ERROR was due to out() returning
1140 non-zero. (in() will always be called before out(), so strm->next_in is
1141 assured to be defined if out() returns non-zero.) Note that inflateBack()
1154 /* Return flags indicating compile-time options.
1164 9: ASMV or ASMINF -- use ASM code
1165 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1168 One-time table building (smaller code, but not thread-safe if true):
1169 12: BUILDFIXED -- build static block decoding tables when needed (not supported by zlib-ng)
1170 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1174 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1176 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1178 18-19: 0 (reserved)
1181 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1182 21: FASTEST -- deflate algorithm with only one, lowest compression level
1186 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1187 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1188 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1191 27-31: 0 (reserved)
1199 stream-oriented functions. To simplify the interface, some default options
1200 are assumed (compression level and memory usage, standard memory allocation
1211 compressed data. compress() is equivalent to compress2() with a level
1220 unsigned long sourceLen, int level);
1222 Compresses the source buffer into the destination buffer. The level
1231 Z_STREAM_ERROR if the level parameter is invalid.
1273 "gz". The gzip format is different from the zlib format. gzip is a gzip
1277 typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */
1284 but can also include a compression level ("wb9") or a strategy: 'f' for
1285 filtered data as in "wb6f", 'h' for Huffman-only compression as in "wb1h",
1286 'R' for run-length encoding as in "wb1R", or 'F' for fixed code compression
1307 reading, this will be detected automatically by looking for the magic two-
1329 double-close()ing the file descriptor. Both gzclose() and fclose() will
1335 provided, or '+' was provided), or if fd is -1. The file descriptor is not
1337 will not detect if fd is invalid (unless fd is -1).
1352 gzbuffer() returns 0 on success, or -1 on failure, such as being called
1356 Z_EXTERN int Z_EXPORT gzsetparams(gzFile file, int level, int strategy);
1358 Dynamically update the compression level and strategy for file. See the
1385 middle of a gzip stream. Note that gzread does not return -1 in the event
1392 len for end of file, or -1 for error. If len is too large to fit in an int,
1393 then nothing is read, -1 is returned, and the error state is set to
1415 and the end-of-file flag is set. The length of the partial item read is not
1419 file, reseting and retrying on end-of-file, when size is not 1.
1443 uncompressed bytes actually written, or a negative zlib error code in case
1449 zlib was compiled with the insecure functions sprintf() or vsprintf(),
1456 Compress and write the given null-terminated string s to file, excluding
1459 gzputs returns the number of characters written, or -1 in case of error.
1464 Read and decompress bytes from file into buf, until len-1 characters are
1466 end-of-file condition is encountered. If any characters are read or if len
1468 are read due to an end-of-file or len is less than one, then the buffer is
1471 gzgets returns buf which is a null-terminated string, or it returns NULL
1472 for end-of-file or in case of error. If there was an error, the contents at
1479 returns the value that was written, or -1 in case of error.
1484 Read and decompress one byte from file. gzgetc returns this byte or -1
1494 the next read. At least one character of push-back is always allowed.
1495 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
1496 fail if c is -1, and may fail if a character has been pushed but not read
1506 deflate() function. The return value is the zlib error number (see function
1532 the beginning of the uncompressed stream, or -1 in case of error, in
1562 be used for a progress indicator. On error, gzoffset() returns -1.
1567 Return true (1) if the end-of-file indicator for file has been set while
1568 reading, false (0) otherwise. Note that the end-of-file indicator is set
1576 unless the end-of-file indicator is reset by gzclearerr() and the input file
1597 linking statically, using gzdirect() will include all of the zlib code for
1619 using these instead of gzclose() is that they avoid linking in zlib
1623 zlib library.
1629 errnum is set to zlib error number. If an error occurred in the file system
1638 gzerror() should be used to distinguish errors from end-of-file for those
1644 Clear the error and end-of-file flags for file. This is analogous to the
1660 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1661 return the updated checksum. An Adler-32 value is in the range of a 32-bit
1665 An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
1686 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1687 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1688 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1696 Update a running CRC-32 with the bytes buf[0..len-1] and return the
1697 updated CRC-32. A CRC-32 value is in the range of a 32-bit unsigned integer.
1699 crc. Pre- and post-conditioning (one's complement) is performed within this
1720 Combine two CRC-32 check values into one. For two sequences of bytes,
1721 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1722 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1746 /* deflateInit and inflateInit are macros to allow checking the zlib version
1749 Z_EXTERN int Z_EXPORT deflateInit_(z_stream *strm, int level, const char *version, int stream_size);
1751 Z_EXTERN int Z_EXPORT deflateInit2_(z_stream *strm, int level, int method, int windowBits, int me…
1756 #define deflateInit(strm, level) deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) argument
1758 #define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ argument
1759 deflateInit2_((strm), (level), (method), (windowBits), (memLevel), \
1779 # define gzgetc(g) ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
1781 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
1784 * functions are changed to 64 bits) -- in case these are set on systems