Lines Matching +full:dynamic +full:- +full:range +full:- +full:compressor
1 /* zlib.h -- interface of the 'zlib' general purpose compression library
4 Copyright (C) 1995-2024 Jean-loup Gailly and Mark Adler
6 This software is provided 'as-is', without any express or implied
22 Jean-loup Gailly Mark Adler
48 The 'zlib' compression library provides in-memory compression and
59 The compressed data format used by default by the in-memory functions is
72 and on communications channels. The gzip format was designed for single-
104 uLong adler; /* Adler-32 or CRC-32 value of the uncompressed data */
122 Bytef *name; /* pointer to zero-terminated file name or Z_NULL */
124 Bytef *comment; /* pointer to zero-terminated comment or Z_NULL */
146 If zlib is used in a multi-threaded application, zalloc and zfree must be
147 thread safe. In that case, zlib is thread-safe. When zalloc and zfree are
151 On 16-bit systems, the functions zalloc and zfree must be able to allocate
158 the library with -DMAX_WBITS=14 (see zconf.h).
180 #define Z_ERRNO (-1)
181 #define Z_STREAM_ERROR (-2)
182 #define Z_DATA_ERROR (-3)
183 #define Z_MEM_ERROR (-4)
184 #define Z_BUF_ERROR (-5)
185 #define Z_VERSION_ERROR (-6)
193 #define Z_DEFAULT_COMPRESSION (-1)
260 - Compress more input starting at next_in and update next_in and avail_in
265 - Generate more output starting at next_out and update next_out and avail_out
309 the data provided so far to the compressor. It may need to wait for the next
321 avail_out), until the flush is complete (deflate returns with non-zero
341 deflate() sets strm->adler to the Adler-32 checksum of all input read
343 strm->adler will be the CRC-32 checksum of the input read so far. (See
346 deflate() may update strm->data_type if it can make a good guess about
396 implementation of inflateInit() does not process any header information --
411 - Decompress more input starting at next_in and update next_in and avail_in
417 - Generate more output starting at next_out and update next_out and avail_out
443 To assist in this, on return inflate() always sets strm->data_type to the
444 number of unused bits in the last byte taken from strm->next_in, plus 64 if
446 128 if inflate() returned immediately after decoding an end-of-block code or
448 stream. The end-of-block will not be indicated until all of the uncompressed
449 data from that block has been written to strm->next_out. The number of
460 256 is added to the value of strm->data_type when inflate() returns
469 saved by the compressor for this purpose.) The use of Z_FINISH is not
487 below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
488 chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
489 strm->adler to the Adler-32 checksum of all output produced so far (that is,
491 below. At the end of the stream, inflate() checks that its computed Adler-32
492 checksum is equal to that saved by the compressor and returns Z_STREAM_END
495 inflate() can decompress and check either zlib-wrapped or gzip-wrapped
499 gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
500 produced so far. The CRC-32 is checked against the gzip trailer, as is the
508 value, in which case strm->msg points to a string with a more specific
553 (the size of the history buffer). It should be in the range 8..15 for this
560 will result in 9 (a 512-byte window). In that case, providing 8 to
566 windowBits can also be -8..-15 for raw deflate. In this case, -windowBits
576 being written, strm->adler is a CRC-32 instead of an Adler-32.
578 For raw deflate or gzip encoding, a request for a 256-byte window is
591 string match), or Z_RLE to limit match distances to one (run-length
600 Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
623 compressor and decompressor must use exactly the same dictionary (see
641 Upon return of this function, strm->adler is set to the Adler-32 value
643 which dictionary has been used by the compressor. (The Adler-32 value
645 actually used by the compressor.) If a raw deflate was requested, then the
646 Adler-32 value is not computed and strm->adler is not set.
670 up to 258 bytes long. If the application needs the last window-size bytes of
683 tried, for example when there are several ways of pre-processing the input
816 ignored -- the extra flags are set according to the compression level). The
820 the current versions of the command-line version of gzip (up through version
821 1.3.x) do not support header crc's, and will report that it is a "multi-part
842 size (the size of the history buffer). It should be in the range 8..15 for
853 windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
860 recommended that a check value such as an Adler-32 or a CRC-32 be applied to
868 return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a
869 CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see
884 of inflateInit2() does not process any header information -- that is
894 if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
895 can be determined from the Adler-32 value returned by that call of inflate.
896 The compressor and decompressor must use exactly the same dictionary (see
906 expected one (incorrect Adler-32 value). inflateSetDictionary does not
1011 return value down 16 bits. If the upper value is -1 and the lower value is
1013 If the upper value is -1 and the lower value is non-zero, then inflate is in
1015 bytes from the input remaining to copy. If the upper value is not -1, then
1031 inflateMark returns the value noted above, or -65536 if the provided
1041 As inflate() processes the gzip stream, head->done is zero until the header
1042 is completed, at which time head->done is set to one. If a zlib stream is
1043 being decoded, then head->done is set to -1 to indicate that there will be
1081 before the call. If zalloc and zfree are Z_NULL, then the default library-
1083 logarithm of the window size, in the range 8..15. window is a caller
1105 inflateBack() does a raw inflate with a single call using a call-back
1114 and to initialize the state with the user-provided window buffer.
1134 there is no input available, in() must return zero -- buf is ignored in that
1135 case -- and inflateBack() will return a buffer error. inflateBack() will
1136 call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
1137 out() should return zero on success, or non-zero on failure. If out()
1138 returns non-zero, inflateBack() will return with an error. Neither in() nor
1141 The length written by out() will be at most the window size. Any non-zero
1145 setting strm->next_in and strm->avail_in. If that input is exhausted, then
1146 in() will be called. Therefore strm->next_in must be initialized before
1147 calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called
1148 immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in
1149 must also be initialized, and then if strm->avail_in is not zero, input will
1150 initially be taken from strm->next_in[0 .. strm->avail_in - 1].
1154 descriptors can be optionally used to pass any information that the caller-
1157 On return, inflateBack() will set strm->next_in and strm->avail_in to
1161 in the deflate stream (in which case strm->msg is set to indicate the nature
1164 using strm->next_in which will be Z_NULL only if in() returned an error. If
1165 strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
1166 non-zero. (in() will always be called before out(), so strm->next_in is
1167 assured to be defined if out() returns non-zero.) Note that inflateBack()
1180 /* Return flags indicating compile-time options.
1190 9: ASMV or ASMINF -- use ASM code
1191 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
1194 One-time table building (smaller code, but not thread-safe if true):
1195 12: BUILDFIXED -- build static block decoding tables when needed
1196 13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
1200 16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
1202 17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
1204 18-19: 0 (reserved)
1207 20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
1208 21: FASTEST -- deflate algorithm with only one, lowest compression level
1212 24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
1213 25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
1214 26: 0 = returns value, 1 = void -- 1 means inferred string length returned
1217 27-31: 0 (reserved)
1226 stream-oriented functions. To simplify the interface, some default options
1277 previously by the compressor and transmitted to the decompressor by some
1308 typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */
1316 filtered data as in "wb6f", 'h' for Huffman-only compression as in "wb1h",
1317 'R' for run-length encoding as in "wb1R", or 'F' for fixed code compression
1338 reading, this will be detected automatically by looking for the magic two-
1360 double-close()ing the file descriptor. Both gzclose() and fclose() will
1366 provided, or '+' was provided), or if fd is -1. The file descriptor is not
1368 will not detect if fd is invalid (unless fd is -1).
1383 gzbuffer() returns 0 on success, or -1 on failure, such as being called
1416 middle of a gzip stream. Note that gzread does not return -1 in the event
1423 len for end of file, or -1 for error. If len is too large to fit in an int,
1424 then nothing is read, -1 is returned, and the error state is set to
1447 and the end-of-file flag is set. The length of the partial item read is not
1451 file, resetting and retrying on end-of-file, when size is not 1.
1491 Compress and write the given null-terminated string s to file, excluding
1494 gzputs returns the number of characters written, or -1 in case of error.
1499 Read and decompress bytes from file into buf, until len-1 characters are
1501 end-of-file condition is encountered. If any characters are read or if len
1503 are read due to an end-of-file or len is less than one, then the buffer is
1506 gzgets returns buf which is a null-terminated string, or it returns NULL
1507 for end-of-file or in case of error. If there was an error, the contents at
1514 returns the value that was written, or -1 in case of error.
1519 Read and decompress one byte from file. gzgetc returns this byte or -1
1529 the next read. At least one character of push-back is always allowed.
1530 gzungetc() returns the character pushed, or -1 on failure. gzungetc() will
1531 fail if c is -1, and may fail if a character has been pushed but not read
1568 the beginning of the uncompressed stream, or -1 in case of error, in
1598 be used for a progress indicator. On error, gzoffset() returns -1.
1603 Return true (1) if the end-of-file indicator for file has been set while
1604 reading, false (0) otherwise. Note that the end-of-file indicator is set
1612 unless the end-of-file indicator is reset by gzclearerr() and the input file
1674 gzerror() should be used to distinguish errors from end-of-file for those
1680 Clear the error and end-of-file flags for file. This is analogous to the
1697 Update a running Adler-32 checksum with the bytes buf[0..len-1] and
1698 return the updated checksum. An Adler-32 value is in the range of a 32-bit
1702 An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
1725 Combine two Adler-32 checksums into one. For two sequences of bytes, seq1
1726 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
1727 each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of
1735 Update a running CRC-32 with the bytes buf[0..len-1] and return the
1736 updated CRC-32. A CRC-32 value is in the range of a 32-bit unsigned integer.
1738 crc. Pre- and post-conditioning (one's complement) is performed within this
1760 Combine two CRC-32 check values into one. For two sequences of bytes,
1761 seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
1762 calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32
1764 len2. len2 must be non-negative.
1771 crc32_combine_op(). len2 must be non-negative.
1851 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
1854 ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
1857 /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
1860 * functions are changed to 64 bits) -- in case these are set on systems