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Diffstat (limited to 'cpukit/include/zlib.h')
| -rw-r--r-- | cpukit/include/zlib.h | 912 |
1 files changed, 617 insertions, 295 deletions
diff --git a/cpukit/include/zlib.h b/cpukit/include/zlib.h index bfbba83e8e..953cb5012d 100644 --- a/cpukit/include/zlib.h +++ b/cpukit/include/zlib.h @@ -1,7 +1,7 @@ /* zlib.h -- interface of the 'zlib' general purpose compression library - version 1.2.5, April 19th, 2010 + version 1.2.13, October 13th, 2022 - Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler + Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages @@ -24,8 +24,8 @@ The data format used by the zlib library is described by RFCs (Request for - Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt - (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). + Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950 + (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format). */ #ifndef ZLIB_H @@ -37,11 +37,11 @@ extern "C" { #endif -#define ZLIB_VERSION "1.2.5" -#define ZLIB_VERNUM 0x1250 +#define ZLIB_VERSION "1.2.13" +#define ZLIB_VERNUM 0x12d0 #define ZLIB_VER_MAJOR 1 #define ZLIB_VER_MINOR 2 -#define ZLIB_VER_REVISION 5 +#define ZLIB_VER_REVISION 13 #define ZLIB_VER_SUBREVISION 0 /* @@ -65,7 +65,8 @@ extern "C" { with "gz". The gzip format is different from the zlib format. gzip is a gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. - This library can optionally read and write gzip streams in memory as well. + This library can optionally read and write gzip and raw deflate streams in + memory as well. The zlib format was designed to be compact and fast for use in memory and on communications channels. The gzip format was designed for single- @@ -74,7 +75,7 @@ extern "C" { The library does not install any signal handler. The decoder checks the consistency of the compressed data, so the library should never crash - even in case of corrupted input. + even in the case of corrupted input. */ typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); @@ -83,23 +84,24 @@ typedef void (*free_func) OF((voidpf opaque, voidpf address)); struct internal_state; typedef struct z_stream_s { - Bytef *next_in; /* next input byte */ + z_const Bytef *next_in; /* next input byte */ uInt avail_in; /* number of bytes available at next_in */ - uLong total_in; /* total nb of input bytes read so far */ + uLong total_in; /* total number of input bytes read so far */ - Bytef *next_out; /* next output byte should be put there */ + Bytef *next_out; /* next output byte will go here */ uInt avail_out; /* remaining free space at next_out */ - uLong total_out; /* total nb of bytes output so far */ + uLong total_out; /* total number of bytes output so far */ - char *msg; /* last error message, NULL if no error */ + z_const char *msg; /* last error message, NULL if no error */ struct internal_state FAR *state; /* not visible by applications */ alloc_func zalloc; /* used to allocate the internal state */ free_func zfree; /* used to free the internal state */ voidpf opaque; /* private data object passed to zalloc and zfree */ - int data_type; /* best guess about the data type: binary or text */ - uLong adler; /* adler32 value of the uncompressed data */ + int data_type; /* best guess about the data type: binary or text + for deflate, or the decoding state for inflate */ + uLong adler; /* Adler-32 or CRC-32 value of the uncompressed data */ uLong reserved; /* reserved for future use */ } z_stream; @@ -142,7 +144,9 @@ typedef gz_header FAR *gz_headerp; zalloc must return Z_NULL if there is not enough memory for the object. If zlib is used in a multi-threaded application, zalloc and zfree must be - thread safe. + thread safe. In that case, zlib is thread-safe. When zalloc and zfree are + Z_NULL on entry to the initialization function, they are set to internal + routines that use the standard library functions malloc() and free(). On 16-bit systems, the functions zalloc and zfree must be able to allocate exactly 65536 bytes, but will not be required to allocate more than this if @@ -155,7 +159,7 @@ typedef gz_header FAR *gz_headerp; The fields total_in and total_out can be used for statistics or progress reports. After compression, total_in holds the total size of the - uncompressed data and may be saved for use in the decompressor (particularly + uncompressed data and may be saved for use by the decompressor (particularly if the decompressor wants to decompress everything in a single step). */ @@ -200,7 +204,7 @@ typedef gz_header FAR *gz_headerp; #define Z_TEXT 1 #define Z_ASCII Z_TEXT /* for compatibility with 1.2.2 and earlier */ #define Z_UNKNOWN 2 -/* Possible values of the data_type field (though see inflate()) */ +/* Possible values of the data_type field for deflate() */ #define Z_DEFLATED 8 /* The deflate compression method (the only one supported in this version) */ @@ -258,11 +262,11 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); enough room in the output buffer), next_in and avail_in are updated and processing will resume at this point for the next call of deflate(). - - Provide more output starting at next_out and update next_out and avail_out + - Generate more output starting at next_out and update next_out and avail_out accordingly. This action is forced if the parameter flush is non zero. Forcing flush frequently degrades the compression ratio, so this parameter - should be set only when necessary (in interactive applications). Some - output may be provided even if flush is not set. + should be set only when necessary. Some output may be provided even if + flush is zero. Before the call of deflate(), the application should ensure that at least one of the actions is possible, by providing more input and/or consuming more @@ -271,7 +275,9 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); output when it wants, for example when the output buffer is full (avail_out == 0), or after each call of deflate(). If deflate returns Z_OK and with zero avail_out, it must be called again after making room in the output - buffer because there might be more output pending. + buffer because there might be more output pending. See deflatePending(), + which can be used if desired to determine whether or not there is more output + in that case. Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to decide how much data to accumulate before producing output, in order to @@ -292,8 +298,8 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. This completes the current deflate block and follows it with an empty fixed codes block that is 10 bits long. This assures that enough bytes are output - in order for the decompressor to finish the block before the empty fixed code - block. + in order for the decompressor to finish the block before the empty fixed + codes block. If flush is set to Z_BLOCK, a deflate block is completed and emitted, as for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to @@ -319,33 +325,38 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); If the parameter flush is set to Z_FINISH, pending input is processed, pending output is flushed and deflate returns with Z_STREAM_END if there was - enough output space; if deflate returns with Z_OK, this function must be - called again with Z_FINISH and more output space (updated avail_out) but no - more input data, until it returns with Z_STREAM_END or an error. After - deflate has returned Z_STREAM_END, the only possible operations on the stream - are deflateReset or deflateEnd. - - Z_FINISH can be used immediately after deflateInit if all the compression - is to be done in a single step. In this case, avail_out must be at least the - value returned by deflateBound (see below). If deflate does not return - Z_STREAM_END, then it must be called again as described above. - - deflate() sets strm->adler to the adler32 checksum of all input read - so far (that is, total_in bytes). + enough output space. If deflate returns with Z_OK or Z_BUF_ERROR, this + function must be called again with Z_FINISH and more output space (updated + avail_out) but no more input data, until it returns with Z_STREAM_END or an + error. After deflate has returned Z_STREAM_END, the only possible operations + on the stream are deflateReset or deflateEnd. + + Z_FINISH can be used in the first deflate call after deflateInit if all the + compression is to be done in a single step. In order to complete in one + call, avail_out must be at least the value returned by deflateBound (see + below). Then deflate is guaranteed to return Z_STREAM_END. If not enough + output space is provided, deflate will not return Z_STREAM_END, and it must + be called again as described above. + + deflate() sets strm->adler to the Adler-32 checksum of all input read + so far (that is, total_in bytes). If a gzip stream is being generated, then + strm->adler will be the CRC-32 checksum of the input read so far. (See + deflateInit2 below.) deflate() may update strm->data_type if it can make a good guess about - the input data type (Z_BINARY or Z_TEXT). In doubt, the data is considered - binary. This field is only for information purposes and does not affect the - compression algorithm in any manner. + the input data type (Z_BINARY or Z_TEXT). If in doubt, the data is + considered binary. This field is only for information purposes and does not + affect the compression algorithm in any manner. deflate() returns Z_OK if some progress has been made (more input processed or more output produced), Z_STREAM_END if all input has been consumed and all output has been produced (only when flush is set to Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example - if next_in or next_out was Z_NULL), Z_BUF_ERROR if no progress is possible - (for example avail_in or avail_out was zero). Note that Z_BUF_ERROR is not - fatal, and deflate() can be called again with more input and more output - space to continue compressing. + if next_in or next_out was Z_NULL or the state was inadvertently written over + by the application), or Z_BUF_ERROR if no progress is possible (for example + avail_in or avail_out was zero). Note that Z_BUF_ERROR is not fatal, and + deflate() can be called again with more input and more output space to + continue compressing. */ @@ -368,23 +379,21 @@ ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); Initializes the internal stream state for decompression. The fields next_in, avail_in, zalloc, zfree and opaque must be initialized before by - the caller. If next_in is not Z_NULL and avail_in is large enough (the - exact value depends on the compression method), inflateInit determines the - compression method from the zlib header and allocates all data structures - accordingly; otherwise the allocation will be deferred to the first call of - inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to - use default allocation functions. + the caller. In the current version of inflate, the provided input is not + read or consumed. The allocation of a sliding window will be deferred to + the first call of inflate (if the decompression does not complete on the + first call). If zalloc and zfree are set to Z_NULL, inflateInit updates + them to use default allocation functions. inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough memory, Z_VERSION_ERROR if the zlib library version is incompatible with the version assumed by the caller, or Z_STREAM_ERROR if the parameters are invalid, such as a null pointer to the structure. msg is set to null if - there is no error message. inflateInit does not perform any decompression - apart from possibly reading the zlib header if present: actual decompression - will be done by inflate(). (So next_in and avail_in may be modified, but - next_out and avail_out are unused and unchanged.) The current implementation - of inflateInit() does not process any header information -- that is deferred - until inflate() is called. + there is no error message. inflateInit does not perform any decompression. + Actual decompression will be done by inflate(). So next_in, and avail_in, + next_out, and avail_out are unused and unchanged. The current + implementation of inflateInit() does not process any header information -- + that is deferred until inflate() is called. */ @@ -400,17 +409,20 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); - Decompress more input starting at next_in and update next_in and avail_in accordingly. If not all input can be processed (because there is not - enough room in the output buffer), next_in is updated and processing will - resume at this point for the next call of inflate(). + enough room in the output buffer), then next_in and avail_in are updated + accordingly, and processing will resume at this point for the next call of + inflate(). - - Provide more output starting at next_out and update next_out and avail_out + - Generate more output starting at next_out and update next_out and avail_out accordingly. inflate() provides as much output as possible, until there is no more input data or no more space in the output buffer (see below about the flush parameter). Before the call of inflate(), the application should ensure that at least one of the actions is possible, by providing more input and/or consuming more - output, and updating the next_* and avail_* values accordingly. The + output, and updating the next_* and avail_* values accordingly. If the + caller of inflate() does not provide both available input and available + output space, it is possible that there will be no progress made. The application can consume the uncompressed output when it wants, for example when the output buffer is full (avail_out == 0), or after each call of inflate(). If inflate returns Z_OK and with zero avail_out, it must be @@ -427,7 +439,7 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); gets to the end of that block, or when it runs out of data. The Z_BLOCK option assists in appending to or combining deflate streams. - Also to assist in this, on return inflate() will set strm->data_type to the + To assist in this, on return inflate() always sets strm->data_type to the number of unused bits in the last byte taken from strm->next_in, plus 64 if inflate() is currently decoding the last block in the deflate stream, plus 128 if inflate() returned immediately after decoding an end-of-block code or @@ -451,48 +463,57 @@ ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); error. However if all decompression is to be performed in a single step (a single call of inflate), the parameter flush should be set to Z_FINISH. In this case all pending input is processed and all pending output is flushed; - avail_out must be large enough to hold all the uncompressed data. (The size - of the uncompressed data may have been saved by the compressor for this - purpose.) The next operation on this stream must be inflateEnd to deallocate - the decompression state. The use of Z_FINISH is never required, but can be - used to inform inflate that a faster approach may be used for the single - inflate() call. + avail_out must be large enough to hold all of the uncompressed data for the + operation to complete. (The size of the uncompressed data may have been + saved by the compressor for this purpose.) The use of Z_FINISH is not + required to perform an inflation in one step. However it may be used to + inform inflate that a faster approach can be used for the single inflate() + call. Z_FINISH also informs inflate to not maintain a sliding window if the + stream completes, which reduces inflate's memory footprint. If the stream + does not complete, either because not all of the stream is provided or not + enough output space is provided, then a sliding window will be allocated and + inflate() can be called again to continue the operation as if Z_NO_FLUSH had + been used. In this implementation, inflate() always flushes as much output as possible to the output buffer, and always uses the faster approach on the - first call. So the only effect of the flush parameter in this implementation - is on the return value of inflate(), as noted below, or when it returns early - because Z_BLOCK or Z_TREES is used. + first call. So the effects of the flush parameter in this implementation are + on the return value of inflate() as noted below, when inflate() returns early + when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of + memory for a sliding window when Z_FINISH is used. If a preset dictionary is needed after this call (see inflateSetDictionary - below), inflate sets strm->adler to the adler32 checksum of the dictionary + below), inflate sets strm->adler to the Adler-32 checksum of the dictionary chosen by the compressor and returns Z_NEED_DICT; otherwise it sets - strm->adler to the adler32 checksum of all output produced so far (that is, + strm->adler to the Adler-32 checksum of all output produced so far (that is, total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described - below. At the end of the stream, inflate() checks that its computed adler32 + below. At the end of the stream, inflate() checks that its computed Adler-32 checksum is equal to that saved by the compressor and returns Z_STREAM_END only if the checksum is correct. inflate() can decompress and check either zlib-wrapped or gzip-wrapped deflate data. The header type is detected automatically, if requested when initializing with inflateInit2(). Any information contained in the gzip - header is not retained, so applications that need that information should - instead use raw inflate, see inflateInit2() below, or inflateBack() and - perform their own processing of the gzip header and trailer. + header is not retained unless inflateGetHeader() is used. When processing + gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output + produced so far. The CRC-32 is checked against the gzip trailer, as is the + uncompressed length, modulo 2^32. inflate() returns Z_OK if some progress has been made (more input processed or more output produced), Z_STREAM_END if the end of the compressed data has been reached and all uncompressed output has been produced, Z_NEED_DICT if a preset dictionary is needed at this point, Z_DATA_ERROR if the input data was corrupted (input stream not conforming to the zlib format or incorrect check - value), Z_STREAM_ERROR if the stream structure was inconsistent (for example - next_in or next_out was Z_NULL), Z_MEM_ERROR if there was not enough memory, - Z_BUF_ERROR if no progress is possible or if there was not enough room in the - output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and + value, in which case strm->msg points to a string with a more specific + error), Z_STREAM_ERROR if the stream structure was inconsistent (for example + next_in or next_out was Z_NULL, or the state was inadvertently written over + by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR + if no progress was possible or if there was not enough room in the output + buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and inflate() can be called again with more input and more output space to continue decompressing. If Z_DATA_ERROR is returned, the application may then call inflateSync() to look for a good compression block if a partial - recovery of the data is desired. + recovery of the data is to be attempted. */ @@ -502,9 +523,8 @@ ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); This function discards any unprocessed input and does not flush any pending output. - inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state - was inconsistent. In the error case, msg may be set but then points to a - static string (which must not be deallocated). + inflateEnd returns Z_OK if success, or Z_STREAM_ERROR if the stream state + was inconsistent. */ @@ -523,8 +543,7 @@ ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, int strategy)); This is another version of deflateInit with more compression options. The - fields next_in, zalloc, zfree and opaque must be initialized before by the - caller. + fields zalloc, zfree and opaque must be initialized before by the caller. The method parameter is the compression method. It must be Z_DEFLATED in this version of the library. @@ -535,16 +554,29 @@ ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm, compression at the expense of memory usage. The default value is 15 if deflateInit is used instead. + For the current implementation of deflate(), a windowBits value of 8 (a + window size of 256 bytes) is not supported. As a result, a request for 8 + will result in 9 (a 512-byte window). In that case, providing 8 to + inflateInit2() will result in an error when the zlib header with 9 is + checked against the initialization of inflate(). The remedy is to not use 8 + with deflateInit2() with this initialization, or at least in that case use 9 + with inflateInit2(). + windowBits can also be -8..-15 for raw deflate. In this case, -windowBits determines the window size. deflate() will then generate raw deflate data - with no zlib header or trailer, and will not compute an adler32 check value. + with no zlib header or trailer, and will not compute a check value. windowBits can also be greater than 15 for optional gzip encoding. Add 16 to windowBits to write a simple gzip header and trailer around the compressed data instead of a zlib wrapper. The gzip header will have no file name, no extra data, no comment, no modification time (set to zero), no - header crc, and the operating system will be set to 255 (unknown). If a - gzip stream is being written, strm->adler is a crc32 instead of an adler32. + header crc, and the operating system will be set to the appropriate value, + if the operating system was determined at compile time. If a gzip stream is + being written, strm->adler is a CRC-32 instead of an Adler-32. + + For raw deflate or gzip encoding, a request for a 256-byte window is + rejected as invalid, since only the zlib header provides a means of + transmitting the window size to the decompressor. The memLevel parameter specifies how much memory should be allocated for the internal compression state. memLevel=1 uses minimum memory but is @@ -580,10 +612,15 @@ ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, uInt dictLength)); /* Initializes the compression dictionary from the given byte sequence - without producing any compressed output. This function must be called - immediately after deflateInit, deflateInit2 or deflateReset, before any call - of deflate. The compressor and decompressor must use exactly the same - dictionary (see inflateSetDictionary). + without producing any compressed output. When using the zlib format, this + function must be called immediately after deflateInit, deflateInit2 or + deflateReset, and before any call of deflate. When doing raw deflate, this + function must be called either before any call of deflate, or immediately + after the completion of a deflate block, i.e. after all input has been + consumed and all output has been delivered when using any of the flush + options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH. The + compressor and decompressor must use exactly the same dictionary (see + inflateSetDictionary). The dictionary should consist of strings (byte sequences) that are likely to be encountered later in the data to be compressed, with the most commonly @@ -600,18 +637,40 @@ ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, addition, the current implementation of deflate will use at most the window size minus 262 bytes of the provided dictionary. - Upon return of this function, strm->adler is set to the adler32 value + Upon return of this function, strm->adler is set to the Adler-32 value of the dictionary; the decompressor may later use this value to determine - which dictionary has been used by the compressor. (The adler32 value + which dictionary has been used by the compressor. (The Adler-32 value applies to the whole dictionary even if only a subset of the dictionary is actually used by the compressor.) If a raw deflate was requested, then the - adler32 value is not computed and strm->adler is not set. + Adler-32 value is not computed and strm->adler is not set. deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is inconsistent (for example if deflate has already been called for this stream - or if the compression method is bsort). deflateSetDictionary does not - perform any compression: this will be done by deflate(). + or if not at a block boundary for raw deflate). deflateSetDictionary does + not perform any compression: this will be done by deflate(). +*/ + +ZEXTERN int ZEXPORT deflateGetDictionary OF((z_streamp strm, + Bytef *dictionary, + uInt *dictLength)); +/* + Returns the sliding dictionary being maintained by deflate. dictLength is + set to the number of bytes in the dictionary, and that many bytes are copied + to dictionary. dictionary must have enough space, where 32768 bytes is + always enough. If deflateGetDictionary() is called with dictionary equal to + Z_NULL, then only the dictionary length is returned, and nothing is copied. + Similarly, if dictLength is Z_NULL, then it is not set. + + deflateGetDictionary() may return a length less than the window size, even + when more than the window size in input has been provided. It may return up + to 258 bytes less in that case, due to how zlib's implementation of deflate + manages the sliding window and lookahead for matches, where matches can be + up to 258 bytes long. If the application needs the last window-size bytes of + input, then that would need to be saved by the application outside of zlib. + + deflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the + stream state is inconsistent. */ ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, @@ -634,10 +693,10 @@ ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); /* - This function is equivalent to deflateEnd followed by deflateInit, - but does not free and reallocate all the internal compression state. The - stream will keep the same compression level and any other attributes that - may have been set by deflateInit2. + This function is equivalent to deflateEnd followed by deflateInit, but + does not free and reallocate the internal compression state. The stream + will leave the compression level and any other attributes that may have been + set unchanged. deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source stream state was inconsistent (such as zalloc or state being Z_NULL). @@ -648,20 +707,37 @@ ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, int strategy)); /* Dynamically update the compression level and compression strategy. The - interpretation of level and strategy is as in deflateInit2. This can be + interpretation of level and strategy is as in deflateInit2(). This can be used to switch between compression and straight copy of the input data, or to switch to a different kind of input data requiring a different strategy. - If the compression level is changed, the input available so far is - compressed with the old level (and may be flushed); the new level will take - effect only at the next call of deflate(). - - Before the call of deflateParams, the stream state must be set as for - a call of deflate(), since the currently available input may have to be - compressed and flushed. In particular, strm->avail_out must be non-zero. - - deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source - stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if - strm->avail_out was zero. + If the compression approach (which is a function of the level) or the + strategy is changed, and if there have been any deflate() calls since the + state was initialized or reset, then the input available so far is + compressed with the old level and strategy using deflate(strm, Z_BLOCK). + There are three approaches for the compression levels 0, 1..3, and 4..9 + respectively. The new level and strategy will take effect at the next call + of deflate(). + + If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does + not have enough output space to complete, then the parameter change will not + take effect. In this case, deflateParams() can be called again with the + same parameters and more output space to try again. + + In order to assure a change in the parameters on the first try, the + deflate stream should be flushed using deflate() with Z_BLOCK or other flush + request until strm.avail_out is not zero, before calling deflateParams(). + Then no more input data should be provided before the deflateParams() call. + If this is done, the old level and strategy will be applied to the data + compressed before deflateParams(), and the new level and strategy will be + applied to the the data compressed after deflateParams(). + + deflateParams returns Z_OK on success, Z_STREAM_ERROR if the source stream + state was inconsistent or if a parameter was invalid, or Z_BUF_ERROR if + there was not enough output space to complete the compression of the + available input data before a change in the strategy or approach. Note that + in the case of a Z_BUF_ERROR, the parameters are not changed. A return + value of Z_BUF_ERROR is not fatal, in which case deflateParams() can be + retried with more output space. */ ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, @@ -688,8 +764,28 @@ ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm, deflation of sourceLen bytes. It must be called after deflateInit() or deflateInit2(), and after deflateSetHeader(), if used. This would be used to allocate an output buffer for deflation in a single pass, and so would be - called before deflate(). -*/ + called before deflate(). If that first deflate() call is provided the + sourceLen input bytes, an output buffer allocated to the size returned by + deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed + to return Z_STREAM_END. Note that it is possible for the compressed size to + be larger than the value returned by deflateBound() if flush options other + than Z_FINISH or Z_NO_FLUSH are used. +*/ + +ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm, + unsigned *pending, + int *bits)); +/* + deflatePending() returns the number of bytes and bits of output that have + been generated, but not yet provided in the available output. The bytes not + provided would be due to the available output space having being consumed. + The number of bits of output not provided are between 0 and 7, where they + await more bits to join them in order to fill out a full byte. If pending + or bits are Z_NULL, then those values are not set. + + deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source + stream state was inconsistent. + */ ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, int bits, @@ -703,8 +799,9 @@ ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, than or equal to 16, and that many of the least significant bits of value will be inserted in the output. - deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source - stream state was inconsistent. + deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough + room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the + source stream state was inconsistent. */ ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, @@ -758,7 +855,7 @@ ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, is for use with other formats that use the deflate compressed data format such as zip. Those formats provide their own check values. If a custom format is developed using the raw deflate format for compressed data, it is - recommended that a check value such as an adler32 or a crc32 be applied to + recommended that a check value such as an Adler-32 or a CRC-32 be applied to the uncompressed data as is done in the zlib, gzip, and zip formats. For most applications, the zlib format should be used as is. Note that comments above on the use in deflateInit2() applies to the magnitude of windowBits. @@ -767,7 +864,12 @@ ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, 32 to windowBits to enable zlib and gzip decoding with automatic header detection, or add 16 to decode only the gzip format (the zlib format will return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a - crc32 instead of an adler32. + CRC-32 instead of an Adler-32. Unlike the gunzip utility and gzread() (see + below), inflate() will *not* automatically decode concatenated gzip members. + inflate() will return Z_STREAM_END at the end of the gzip member. The state + would need to be reset to continue decoding a subsequent gzip member. This + *must* be done if there is more data after a gzip member, in order for the + decompression to be compliant with the gzip standard (RFC 1952). inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough memory, Z_VERSION_ERROR if the zlib library version is incompatible with the @@ -788,34 +890,54 @@ ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, Initializes the decompression dictionary from the given uncompressed byte sequence. This function must be called immediately after a call of inflate, if that call returned Z_NEED_DICT. The dictionary chosen by the compressor - can be determined from the adler32 value returned by that call of inflate. + can be determined from the Adler-32 value returned by that call of inflate. The compressor and decompressor must use exactly the same dictionary (see - deflateSetDictionary). For raw inflate, this function can be called - immediately after inflateInit2() or inflateReset() and before any call of - inflate() to set the dictionary. The application must insure that the - dictionary that was used for compression is provided. + deflateSetDictionary). For raw inflate, this function can be called at any + time to set the dictionary. If the provided dictionary is smaller than the + window and there is already data in the window, then the provided dictionary + will amend what's there. The application must insure that the dictionary + that was used for compression is provided. inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a parameter is invalid (e.g. dictionary being Z_NULL) or the stream state is inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the - expected one (incorrect adler32 value). inflateSetDictionary does not + expected one (incorrect Adler-32 value). inflateSetDictionary does not perform any decompression: this will be done by subsequent calls of inflate(). */ +ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm, + Bytef *dictionary, + uInt *dictLength)); +/* + Returns the sliding dictionary being maintained by inflate. dictLength is + set to the number of bytes in the dictionary, and that many bytes are copied + to dictionary. dictionary must have enough space, where 32768 bytes is + always enough. If inflateGetDictionary() is called with dictionary equal to + Z_NULL, then only the dictionary length is returned, and nothing is copied. + Similarly, if dictLength is Z_NULL, then it is not set. + + inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the + stream state is inconsistent. +*/ + ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); /* - Skips invalid compressed data until a full flush point (see above the - description of deflate with Z_FULL_FLUSH) can be found, or until all + Skips invalid compressed data until a possible full flush point (see above + for the description of deflate with Z_FULL_FLUSH) can be found, or until all available input is skipped. No output is provided. - inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR - if no more input was provided, Z_DATA_ERROR if no flush point has been - found, or Z_STREAM_ERROR if the stream structure was inconsistent. In the - success case, the application may save the current current value of total_in - which indicates where valid compressed data was found. In the error case, - the application may repeatedly call inflateSync, providing more input each - time, until success or end of the input data. + inflateSync searches for a 00 00 FF FF pattern in the compressed data. + All full flush points have this pattern, but not all occurrences of this + pattern are full flush points. + + inflateSync returns Z_OK if a possible full flush point has been found, + Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point + has been found, or Z_STREAM_ERROR if the stream structure was inconsistent. + In the success case, the application may save the current current value of + total_in which indicates where valid compressed data was found. In the + error case, the application may repeatedly call inflateSync, providing more + input each time, until success or end of the input data. */ ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, @@ -837,7 +959,7 @@ ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); /* This function is equivalent to inflateEnd followed by inflateInit, - but does not free and reallocate all the internal decompression state. The + but does not free and reallocate the internal decompression state. The stream will keep attributes that may have been set by inflateInit2. inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source @@ -849,7 +971,9 @@ ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, /* This function is the same as inflateReset, but it also permits changing the wrap and window size requests. The windowBits parameter is interpreted - the same as it is for inflateInit2. + the same as it is for inflateInit2. If the window size is changed, then the + memory allocated for the window is freed, and the window will be reallocated + by inflate() if needed. inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source stream state was inconsistent (such as zalloc or state being Z_NULL), or if @@ -901,7 +1025,7 @@ ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); location in the input stream can be determined from avail_in and data_type as noted in the description for the Z_BLOCK flush parameter for inflate. - inflateMark returns the value noted above or -1 << 16 if the provided + inflateMark returns the value noted above, or -65536 if the provided source stream state was inconsistent. */ @@ -962,12 +1086,13 @@ ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, See inflateBack() for the usage of these routines. inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of - the paramaters are invalid, Z_MEM_ERROR if the internal state could not be + the parameters are invalid, Z_MEM_ERROR if the internal state could not be allocated, or Z_VERSION_ERROR if the version of the library does not match the version of the header file. */ -typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); +typedef unsigned (*in_func) OF((void FAR *, + z_const unsigned char FAR * FAR *)); typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, @@ -975,11 +1100,12 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, out_func out, void FAR *out_desc)); /* inflateBack() does a raw inflate with a single call using a call-back - interface for input and output. This is more efficient than inflate() for - file i/o applications in that it avoids copying between the output and the - sliding window by simply making the window itself the output buffer. This - function trusts the application to not change the output buffer passed by - the output function, at least until inflateBack() returns. + interface for input and output. This is potentially more efficient than + inflate() for file i/o applications, in that it avoids copying between the + output and the sliding window by simply making the window itself the output + buffer. inflate() can be faster on modern CPUs when used with large + buffers. inflateBack() trusts the application to not change the output + buffer passed by the output function, at least until inflateBack() returns. inflateBackInit() must be called first to allocate the internal state and to initialize the state with the user-provided window buffer. @@ -991,9 +1117,9 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, This routine would normally be used in a utility that reads zip or gzip files and writes out uncompressed files. The utility would decode the header and process the trailer on its own, hence this routine expects only - the raw deflate stream to decompress. This is different from the normal - behavior of inflate(), which expects either a zlib or gzip header and - trailer around the deflate stream. + the raw deflate stream to decompress. This is different from the default + behavior of inflate(), which expects a zlib header and trailer around the + deflate stream. inflateBack() uses two subroutines supplied by the caller that are then called by inflateBack() for input and output. inflateBack() calls those @@ -1002,12 +1128,12 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, parameters and return types are defined above in the in_func and out_func typedefs. inflateBack() will call in(in_desc, &buf) which should return the number of bytes of provided input, and a pointer to that input in buf. If - there is no input available, in() must return zero--buf is ignored in that - case--and inflateBack() will return a buffer error. inflateBack() will call - out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. out() - should return zero on success, or non-zero on failure. If out() returns - non-zero, inflateBack() will return with an error. Neither in() nor out() - are permitted to change the contents of the window provided to + there is no input available, in() must return zero -- buf is ignored in that + case -- and inflateBack() will return a buffer error. inflateBack() will + call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1]. + out() should return zero on success, or non-zero on failure. If out() + returns non-zero, inflateBack() will return with an error. Neither in() nor + out() are permitted to change the contents of the window provided to inflateBackInit(), which is also the buffer that out() uses to write from. The length written by out() will be at most the window size. Any non-zero amount of input may be provided by in(). @@ -1035,7 +1161,7 @@ ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, using strm->next_in which will be Z_NULL only if in() returned an error. If strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning non-zero. (in() will always be called before out(), so strm->next_in is - assured to be defined if out() returns non-zero.) Note that inflateBack() + assured to be defined if out() returns non-zero.) Note that inflateBack() cannot return Z_OK. */ @@ -1057,7 +1183,7 @@ ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); 7.6: size of z_off_t Compiler, assembler, and debug options: - 8: DEBUG + 8: ZLIB_DEBUG 9: ASMV or ASMINF -- use ASM code 10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention 11: 0 (reserved) @@ -1088,6 +1214,7 @@ ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); 27-31: 0 (reserved) */ +#ifndef Z_SOLO /* utility functions */ @@ -1106,7 +1233,8 @@ ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, the byte length of the source buffer. Upon entry, destLen is the total size of the destination buffer, which must be at least the value returned by compressBound(sourceLen). Upon exit, destLen is the actual size of the - compressed buffer. + compressed data. compress() is equivalent to compress2() with a level + parameter of Z_DEFAULT_COMPRESSION. compress returns Z_OK if success, Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if there was not enough room in the output @@ -1122,7 +1250,7 @@ ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLongf *destLen, length of the source buffer. Upon entry, destLen is the total size of the destination buffer, which must be at least the value returned by compressBound(sourceLen). Upon exit, destLen is the actual size of the - compressed buffer. + compressed data. compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if there was not enough room in the output buffer, @@ -1145,13 +1273,22 @@ ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, uncompressed data. (The size of the uncompressed data must have been saved previously by the compressor and transmitted to the decompressor by some mechanism outside the scope of this compression library.) Upon exit, destLen - is the actual size of the uncompressed buffer. + is the actual size of the uncompressed data. uncompress returns Z_OK if success, Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR if there was not enough room in the output - buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. + buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. In + the case where there is not enough room, uncompress() will fill the output + buffer with the uncompressed data up to that point. */ +ZEXTERN int ZEXPORT uncompress2 OF((Bytef *dest, uLongf *destLen, + const Bytef *source, uLong *sourceLen)); +/* + Same as uncompress, except that sourceLen is a pointer, where the + length of the source is *sourceLen. On return, *sourceLen is the number of + source bytes consumed. +*/ /* gzip file access functions */ @@ -1162,23 +1299,38 @@ ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, wrapper, documented in RFC 1952, wrapped around a deflate stream. */ -typedef voidp gzFile; /* opaque gzip file descriptor */ +typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */ /* ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); - Opens a gzip (.gz) file for reading or writing. The mode parameter is as - in fopen ("rb" or "wb") but can also include a compression level ("wb9") or - a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only - compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F' - for fixed code compression as in "wb9F". (See the description of - deflateInit2 for more information about the strategy parameter.) Also "a" - can be used instead of "w" to request that the gzip stream that will be - written be appended to the file. "+" will result in an error, since reading - and writing to the same gzip file is not supported. + Open the gzip (.gz) file at path for reading and decompressing, or + compressing and writing. The mode parameter is as in fopen ("rb" or "wb") + but can also include a compression level ("wb9") or a strategy: 'f' for + filtered data as in "wb6f", 'h' for Huffman-only compression as in "wb1h", + 'R' for run-length encoding as in "wb1R", or 'F' for fixed code compression + as in "wb9F". (See the description of deflateInit2 for more information + about the strategy parameter.) 'T' will request transparent writing or + appending with no compression and not using the gzip format. + + "a" can be used instead of "w" to request that the gzip stream that will + be written be appended to the file. "+" will result in an error, since + reading and writing to the same gzip file is not supported. The addition of + "x" when writing will create the file exclusively, which fails if the file + already exists. On systems that support it, the addition of "e" when + reading or writing will set the flag to close the file on an execve() call. + + These functions, as well as gzip, will read and decode a sequence of gzip + streams in a file. The append function of gzopen() can be used to create + such a file. (Also see gzflush() for another way to do this.) When + appending, gzopen does not test whether the file begins with a gzip stream, + nor does it look for the end of the gzip streams to begin appending. gzopen + will simply append a gzip stream to the existing file. gzopen can be used to read a file which is not in gzip format; in this - case gzread will directly read from the file without decompression. + case gzread will directly read from the file without decompression. When + reading, this will be detected automatically by looking for the magic two- + byte gzip header. gzopen returns NULL if the file could not be opened, if there was insufficient memory to allocate the gzFile state, or if an invalid mode was @@ -1189,15 +1341,19 @@ ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); /* - gzdopen associates a gzFile with the file descriptor fd. File descriptors - are obtained from calls like open, dup, creat, pipe or fileno (if the file - has been previously opened with fopen). The mode parameter is as in gzopen. + Associate a gzFile with the file descriptor fd. File descriptors are + obtained from calls like open, dup, creat, pipe or fileno (if the file has + been previously opened with fopen). The mode parameter is as in gzopen. The next call of gzclose on the returned gzFile will also close the file descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd, mode);. The duplicated descriptor should be saved to avoid a leak, since - gzdopen does not close fd if it fails. + gzdopen does not close fd if it fails. If you are using fileno() to get the + file descriptor from a FILE *, then you will have to use dup() to avoid + double-close()ing the file descriptor. Both gzclose() and fclose() will + close the associated file descriptor, so they need to have different file + descriptors. gzdopen returns NULL if there was insufficient memory to allocate the gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not @@ -1208,14 +1364,13 @@ ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); /* - Set the internal buffer size used by this library's functions. The - default buffer size is 8192 bytes. This function must be called after - gzopen() or gzdopen(), and before any other calls that read or write the - file. The buffer memory allocation is always deferred to the first read or - write. Two buffers are allocated, either both of the specified size when - writing, or one of the specified size and the other twice that size when - reading. A larger buffer size of, for example, 64K or 128K bytes will - noticeably increase the speed of decompression (reading). + Set the internal buffer size used by this library's functions for file to + size. The default buffer size is 8192 bytes. This function must be called + after gzopen() or gzdopen(), and before any other calls that read or write + the file. The buffer memory allocation is always deferred to the first read + or write. Three times that size in buffer space is allocated. A larger + buffer size of, for example, 64K or 128K bytes will noticeably increase the + speed of decompression (reading). The new buffer size also affects the maximum length for gzprintf(). @@ -1225,55 +1380,109 @@ ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); /* - Dynamically update the compression level or strategy. See the description - of deflateInit2 for the meaning of these parameters. + Dynamically update the compression level and strategy for file. See the + description of deflateInit2 for the meaning of these parameters. Previously + provided data is flushed before applying the parameter changes. - gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not - opened for writing. + gzsetparams returns Z_OK if success, Z_STREAM_ERROR if the file was not + opened for writing, Z_ERRNO if there is an error writing the flushed data, + or Z_MEM_ERROR if there is a memory allocation error. */ ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); /* - Reads the given number of uncompressed bytes from the compressed file. If - the input file was not in gzip format, gzread copies the given number of - bytes into the buffer. + Read and decompress up to len uncompressed bytes from file into buf. If + the input file is not in gzip format, gzread copies the given number of + bytes into the buffer directly from the file. After reaching the end of a gzip stream in the input, gzread will continue - to read, looking for another gzip stream, or failing that, reading the rest - of the input file directly without decompression. The entire input file - will be read if gzread is called until it returns less than the requested - len. + to read, looking for another gzip stream. Any number of gzip streams may be + concatenated in the input file, and will all be decompressed by gzread(). + If something other than a gzip stream is encountered after a gzip stream, + that remaining trailing garbage is ignored (and no error is returned). + + gzread can be used to read a gzip file that is being concurrently written. + Upon reaching the end of the input, gzread will return with the available + data. If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then + gzclearerr can be used to clear the end of file indicator in order to permit + gzread to be tried again. Z_OK indicates that a gzip stream was completed + on the last gzread. Z_BUF_ERROR indicates that the input file ended in the + middle of a gzip stream. Note that gzread does not return -1 in the event + of an incomplete gzip stream. This error is deferred until gzclose(), which + will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip + stream. Alternatively, gzerror can be used before gzclose to detect this + case. gzread returns the number of uncompressed bytes actually read, less than - len for end of file, or -1 for error. + len for end of file, or -1 for error. If len is too large to fit in an int, + then nothing is read, -1 is returned, and the error state is set to + Z_STREAM_ERROR. +*/ + +ZEXTERN z_size_t ZEXPORT gzfread OF((voidp buf, z_size_t size, z_size_t nitems, + gzFile file)); +/* + Read and decompress up to nitems items of size size from file into buf, + otherwise operating as gzread() does. This duplicates the interface of + stdio's fread(), with size_t request and return types. If the library + defines size_t, then z_size_t is identical to size_t. If not, then z_size_t + is an unsigned integer type that can contain a pointer. + + gzfread() returns the number of full items read of size size, or zero if + the end of the file was reached and a full item could not be read, or if + there was an error. gzerror() must be consulted if zero is returned in + order to determine if there was an error. If the multiplication of size and + nitems overflows, i.e. the product does not fit in a z_size_t, then nothing + is read, zero is returned, and the error state is set to Z_STREAM_ERROR. + + In the event that the end of file is reached and only a partial item is + available at the end, i.e. the remaining uncompressed data length is not a + multiple of size, then the final partial item is nevertheless read into buf + and the end-of-file flag is set. The length of the partial item read is not + provided, but could be inferred from the result of gztell(). This behavior + is the same as the behavior of fread() implementations in common libraries, + but it prevents the direct use of gzfread() to read a concurrently written + file, resetting and retrying on end-of-file, when size is not 1. */ -ZEXTERN int ZEXPORT gzwrite OF((gzFile file, - voidpc buf, unsigned len)); +ZEXTERN int ZEXPORT gzwrite OF((gzFile file, voidpc buf, unsigned len)); /* - Writes the given number of uncompressed bytes into the compressed file. - gzwrite returns the number of uncompressed bytes written or 0 in case of - error. + Compress and write the len uncompressed bytes at buf to file. gzwrite + returns the number of uncompressed bytes written or 0 in case of error. */ -ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); +ZEXTERN z_size_t ZEXPORT gzfwrite OF((voidpc buf, z_size_t size, + z_size_t nitems, gzFile file)); /* - Converts, formats, and writes the arguments to the compressed file under - control of the format string, as in fprintf. gzprintf returns the number of - uncompressed bytes actually written, or 0 in case of error. The number of - uncompressed bytes written is limited to 8191, or one less than the buffer - size given to gzbuffer(). The caller should assure that this limit is not - exceeded. If it is exceeded, then gzprintf() will return an error (0) with - nothing written. In this case, there may also be a buffer overflow with - unpredictable consequences, which is possible only if zlib was compiled with - the insecure functions sprintf() or vsprintf() because the secure snprintf() - or vsnprintf() functions were not available. This can be determined using - zlibCompileFlags(). + Compress and write nitems items of size size from buf to file, duplicating + the interface of stdio's fwrite(), with size_t request and return types. If + the library defines size_t, then z_size_t is identical to size_t. If not, + then z_size_t is an unsigned integer type that can contain a pointer. + + gzfwrite() returns the number of full items written of size size, or zero + if there was an error. If the multiplication of size and nitems overflows, + i.e. the product does not fit in a z_size_t, then nothing is written, zero + is returned, and the error state is set to Z_STREAM_ERROR. +*/ + +ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...)); +/* + Convert, format, compress, and write the arguments (...) to file under + control of the string format, as in fprintf. gzprintf returns the number of + uncompressed bytes actually written, or a negative zlib error code in case + of error. The number of uncompressed bytes written is limited to 8191, or + one less than the buffer size given to gzbuffer(). The caller should assure + that this limit is not exceeded. If it is exceeded, then gzprintf() will + return an error (0) with nothing written. In this case, there may also be a + buffer overflow with unpredictable consequences, which is possible only if + zlib was compiled with the insecure functions sprintf() or vsprintf(), + because the secure snprintf() or vsnprintf() functions were not available. + This can be determined using zlibCompileFlags(). */ ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); /* - Writes the given null-terminated string to the compressed file, excluding + Compress and write the given null-terminated string s to file, excluding the terminating null character. gzputs returns the number of characters written, or -1 in case of error. @@ -1281,11 +1490,12 @@ ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); /* - Reads bytes from the compressed file until len-1 characters are read, or a - newline character is read and transferred to buf, or an end-of-file - condition is encountered. If any characters are read or if len == 1, the - string is terminated with a null character. If no characters are read due - to an end-of-file or len < 1, then the buffer is left untouched. + Read and decompress bytes from file into buf, until len-1 characters are + read, or until a newline character is read and transferred to buf, or an + end-of-file condition is encountered. If any characters are read or if len + is one, the string is terminated with a null character. If no characters + are read due to an end-of-file or len is less than one, then the buffer is + left untouched. gzgets returns buf which is a null-terminated string, or it returns NULL for end-of-file or in case of error. If there was an error, the contents at @@ -1294,20 +1504,23 @@ ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); /* - Writes c, converted to an unsigned char, into the compressed file. gzputc + Compress and write c, converted to an unsigned char, into file. gzputc returns the value that was written, or -1 in case of error. */ ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); /* - Reads one byte from the compressed file. gzgetc returns this byte or -1 - in case of end of file or error. + Read and decompress one byte from file. gzgetc returns this byte or -1 + in case of end of file or error. This is implemented as a macro for speed. + As such, it does not do all of the checking the other functions do. I.e. + it does not check to see if file is NULL, nor whether the structure file + points to has been clobbered or not. */ ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); /* - Push one character back onto the stream to be read as the first character - on the next read. At least one character of push-back is allowed. + Push c back onto the stream for file to be read as the first character on + the next read. At least one character of push-back is always allowed. gzungetc() returns the character pushed, or -1 on failure. gzungetc() will fail if c is -1, and may fail if a character has been pushed but not read yet. If gzungetc is used immediately after gzopen or gzdopen, at least the @@ -1318,14 +1531,14 @@ ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); /* - Flushes all pending output into the compressed file. The parameter flush - is as in the deflate() function. The return value is the zlib error number - (see function gzerror below). gzflush is only permitted when writing. + Flush all pending output to file. The parameter flush is as in the + deflate() function. The return value is the zlib error number (see function + gzerror below). gzflush is only permitted when writing. If the flush parameter is Z_FINISH, the remaining data is written and the gzip stream is completed in the output. If gzwrite() is called again, a new gzip stream will be started in the output. gzread() is able to read such - concatented gzip streams. + concatenated gzip streams. gzflush should be called only when strictly necessary because it will degrade compression if called too often. @@ -1335,8 +1548,8 @@ ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, z_off_t offset, int whence)); - Sets the starting position for the next gzread or gzwrite on the given - compressed file. The offset represents a number of bytes in the + Set the starting position to offset relative to whence for the next gzread + or gzwrite on file. The offset represents a number of bytes in the uncompressed data stream. The whence parameter is defined as in lseek(2); the value SEEK_END is not supported. @@ -1353,18 +1566,18 @@ ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, ZEXTERN int ZEXPORT gzrewind OF((gzFile file)); /* - Rewinds the given file. This function is supported only for reading. + Rewind file. This function is supported only for reading. - gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) + gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET). */ /* ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); - Returns the starting position for the next gzread or gzwrite on the given - compressed file. This position represents a number of bytes in the - uncompressed data stream, and is zero when starting, even if appending or - reading a gzip stream from the middle of a file using gzdopen(). + Return the starting position for the next gzread or gzwrite on file. + This position represents a number of bytes in the uncompressed data stream, + and is zero when starting, even if appending or reading a gzip stream from + the middle of a file using gzdopen(). gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) */ @@ -1372,22 +1585,22 @@ ZEXTERN z_off_t ZEXPORT gztell OF((gzFile file)); /* ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); - Returns the current offset in the file being read or written. This offset - includes the count of bytes that precede the gzip stream, for example when - appending or when using gzdopen() for reading. When reading, the offset - does not include as yet unused buffered input. This information can be used - for a progress indicator. On error, gzoffset() returns -1. + Return the current compressed (actual) read or write offset of file. This + offset includes the count of bytes that precede the gzip stream, for example + when appending or when using gzdopen() for reading. When reading, the + offset does not include as yet unused buffered input. This information can + be used for a progress indicator. On error, gzoffset() returns -1. */ ZEXTERN int ZEXPORT gzeof OF((gzFile file)); /* - Returns true (1) if the end-of-file indicator has been set while reading, - false (0) otherwise. Note that the end-of-file indicator is set only if the - read tried to go past the end of the input, but came up short. Therefore, - just like feof(), gzeof() may return false even if there is no more data to - read, in the event that the last read request was for the exact number of - bytes remaining in the input file. This will happen if the input file size - is an exact multiple of the buffer size. + Return true (1) if the end-of-file indicator for file has been set while + reading, false (0) otherwise. Note that the end-of-file indicator is set + only if the read tried to go past the end of the input, but came up short. + Therefore, just like feof(), gzeof() may return false even if there is no + more data to read, in the event that the last read request was for the exact + number of bytes remaining in the input file. This will happen if the input + file size is an exact multiple of the buffer size. If gzeof() returns true, then the read functions will return no more data, unless the end-of-file indicator is reset by gzclearerr() and the input file @@ -1396,10 +1609,8 @@ ZEXTERN int ZEXPORT gzeof OF((gzFile file)); ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); /* - Returns true (1) if file is being copied directly while reading, or false - (0) if file is a gzip stream being decompressed. This state can change from - false to true while reading the input file if the end of a gzip stream is - reached, but is followed by data that is not another gzip stream. + Return true (1) if file is being copied directly while reading, or false + (0) if file is a gzip stream being decompressed. If the input file is empty, gzdirect() will return true, since the input does not contain a gzip stream. @@ -1408,18 +1619,26 @@ ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); cause buffers to be allocated to allow reading the file to determine if it is a gzip file. Therefore if gzbuffer() is used, it should be called before gzdirect(). + + When writing, gzdirect() returns true (1) if transparent writing was + requested ("wT" for the gzopen() mode), or false (0) otherwise. (Note: + gzdirect() is not needed when writing. Transparent writing must be + explicitly requested, so the application already knows the answer. When + linking statically, using gzdirect() will include all of the zlib code for + gzip file reading and decompression, which may not be desired.) */ ZEXTERN int ZEXPORT gzclose OF((gzFile file)); /* - Flushes all pending output if necessary, closes the compressed file and - deallocates the (de)compression state. Note that once file is closed, you + Flush all pending output for file, if necessary, close file and + deallocate the (de)compression state. Note that once file is closed, you cannot call gzerror with file, since its structures have been deallocated. gzclose must not be called more than once on the same file, just as free must not be called more than once on the same allocation. gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a - file operation error, or Z_OK on success. + file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the + last read ended in the middle of a gzip stream, or Z_OK on success. */ ZEXTERN int ZEXPORT gzclose_r OF((gzFile file)); @@ -1436,10 +1655,10 @@ ZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); /* - Returns the error message for the last error which occurred on the given - compressed file. errnum is set to zlib error number. If an error occurred - in the file system and not in the compression library, errnum is set to - Z_ERRNO and the application may consult errno to get the exact error code. + Return the error message for the last error which occurred on file. + errnum is set to zlib error number. If an error occurred in the file system + and not in the compression library, errnum is set to Z_ERRNO and the + application may consult errno to get the exact error code. The application must not modify the returned string. Future calls to this function may invalidate the previously returned string. If file is @@ -1452,11 +1671,12 @@ ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); /* - Clears the error and end-of-file flags for file. This is analogous to the + Clear the error and end-of-file flags for file. This is analogous to the clearerr() function in stdio. This is useful for continuing to read a gzip file that is being written concurrently. */ +#endif /* !Z_SOLO */ /* checksum functions */ @@ -1469,10 +1689,11 @@ ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); /* Update a running Adler-32 checksum with the bytes buf[0..len-1] and - return the updated checksum. If buf is Z_NULL, this function returns the - required initial value for the checksum. + return the updated checksum. An Adler-32 value is in the range of a 32-bit + unsigned integer. If buf is Z_NULL, this function returns the required + initial value for the checksum. - An Adler-32 checksum is almost as reliable as a CRC32 but can be computed + An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed much faster. Usage example: @@ -1485,6 +1706,12 @@ ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); if (adler != original_adler) error(); */ +ZEXTERN uLong ZEXPORT adler32_z OF((uLong adler, const Bytef *buf, + z_size_t len)); +/* + Same as adler32(), but with a size_t length. +*/ + /* ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, z_off_t len2)); @@ -1492,16 +1719,18 @@ ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for each, adler1 and adler2. adler32_combine() returns the Adler-32 checksum of - seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. + seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. Note + that the z_off_t type (like off_t) is a signed integer. If len2 is + negative, the result has no meaning or utility. */ -ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); +ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); /* Update a running CRC-32 with the bytes buf[0..len-1] and return the - updated CRC-32. If buf is Z_NULL, this function returns the required - initial value for the for the crc. Pre- and post-conditioning (one's - complement) is performed within this function so it shouldn't be done by the - application. + updated CRC-32. A CRC-32 value is in the range of a 32-bit unsigned integer. + If buf is Z_NULL, this function returns the required initial value for the + crc. Pre- and post-conditioning (one's complement) is performed within this + function so it shouldn't be done by the application. Usage example: @@ -1513,6 +1742,12 @@ ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len)); if (crc != original_crc) error(); */ +ZEXTERN uLong ZEXPORT crc32_z OF((uLong crc, const Bytef *buf, + z_size_t len)); +/* + Same as crc32(), but with a size_t length. +*/ + /* ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); @@ -1523,6 +1758,20 @@ ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); len2. */ +/* +ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t len2)); + + Return the operator corresponding to length len2, to be used with + crc32_combine_op(). +*/ + +ZEXTERN uLong ZEXPORT crc32_combine_op OF((uLong crc1, uLong crc2, uLong op)); +/* + Give the same result as crc32_combine(), using op in place of len2. op is + is generated from len2 by crc32_combine_gen(). This will be faster than + crc32_combine() if the generated op is used more than once. +*/ + /* various hacks, don't look :) */ @@ -1543,18 +1792,59 @@ ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, unsigned char FAR *window, const char *version, int stream_size)); -#define deflateInit(strm, level) \ - deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) -#define inflateInit(strm) \ - inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) -#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ - deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ - (strategy), ZLIB_VERSION, sizeof(z_stream)) -#define inflateInit2(strm, windowBits) \ - inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) -#define inflateBackInit(strm, windowBits, window) \ - inflateBackInit_((strm), (windowBits), (window), \ - ZLIB_VERSION, sizeof(z_stream)) +#ifdef Z_PREFIX_SET +# define z_deflateInit(strm, level) \ + deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) +# define z_inflateInit(strm) \ + inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream)) +# define z_deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ + deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ + (strategy), ZLIB_VERSION, (int)sizeof(z_stream)) +# define z_inflateInit2(strm, windowBits) \ + inflateInit2_((strm), (windowBits), ZLIB_VERSION, \ + (int)sizeof(z_stream)) +# define z_inflateBackInit(strm, windowBits, window) \ + inflateBackInit_((strm), (windowBits), (window), \ + ZLIB_VERSION, (int)sizeof(z_stream)) +#else +# define deflateInit(strm, level) \ + deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) +# define inflateInit(strm) \ + inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream)) +# define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ + deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ + (strategy), ZLIB_VERSION, (int)sizeof(z_stream)) +# define inflateInit2(strm, windowBits) \ + inflateInit2_((strm), (windowBits), ZLIB_VERSION, \ + (int)sizeof(z_stream)) +# define inflateBackInit(strm, windowBits, window) \ + inflateBackInit_((strm), (windowBits), (window), \ + ZLIB_VERSION, (int)sizeof(z_stream)) +#endif + +#ifndef Z_SOLO + +/* gzgetc() macro and its supporting function and exposed data structure. Note + * that the real internal state is much larger than the exposed structure. + * This abbreviated structure exposes just enough for the gzgetc() macro. The + * user should not mess with these exposed elements, since their names or + * behavior could change in the future, perhaps even capriciously. They can + * only be used by the gzgetc() macro. You have been warned. + */ +struct gzFile_s { + unsigned have; + unsigned char *next; + z_off64_t pos; +}; +ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file)); /* backward compatibility */ +#ifdef Z_PREFIX_SET +# undef z_gzgetc +# define z_gzgetc(g) \ + ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g)) +#else +# define gzgetc(g) \ + ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g)) +#endif /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if @@ -1562,29 +1852,42 @@ ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, * functions are changed to 64 bits) -- in case these are set on systems * without large file support, _LFS64_LARGEFILE must also be true */ -#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0 +#ifdef Z_LARGE64 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int)); ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile)); ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile)); ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t)); ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t)); + ZEXTERN uLong ZEXPORT crc32_combine_gen64 OF((z_off64_t)); #endif -#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0 -# define gzopen gzopen64 -# define gzseek gzseek64 -# define gztell gztell64 -# define gzoffset gzoffset64 -# define adler32_combine adler32_combine64 -# define crc32_combine crc32_combine64 -# ifdef _LARGEFILE64_SOURCE +#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64) +# ifdef Z_PREFIX_SET +# define z_gzopen z_gzopen64 +# define z_gzseek z_gzseek64 +# define z_gztell z_gztell64 +# define z_gzoffset z_gzoffset64 +# define z_adler32_combine z_adler32_combine64 +# define z_crc32_combine z_crc32_combine64 +# define z_crc32_combine_gen z_crc32_combine_gen64 +# else +# define gzopen gzopen64 +# define gzseek gzseek64 +# define gztell gztell64 +# define gzoffset gzoffset64 +# define adler32_combine adler32_combine64 +# define crc32_combine crc32_combine64 +# define crc32_combine_gen crc32_combine_gen64 +# endif +# ifndef Z_LARGE64 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int)); ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile)); ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile)); ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t)); ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t)); + ZEXTERN uLong ZEXPORT crc32_combine_gen64 OF((z_off_t)); # endif #else ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); @@ -1593,18 +1896,37 @@ ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile)); ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); + ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t)); #endif -/* hack for buggy compilers */ -#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) - struct internal_state {int dummy;}; -#endif +#else /* Z_SOLO */ + + ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); + ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); + ZEXTERN uLong ZEXPORT crc32_combine_gen OF((z_off_t)); + +#endif /* !Z_SOLO */ /* undocumented functions */ ZEXTERN const char * ZEXPORT zError OF((int)); ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp)); -ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void)); +ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table OF((void)); ZEXTERN int ZEXPORT inflateUndermine OF((z_streamp, int)); +ZEXTERN int ZEXPORT inflateValidate OF((z_streamp, int)); +ZEXTERN unsigned long ZEXPORT inflateCodesUsed OF((z_streamp)); +ZEXTERN int ZEXPORT inflateResetKeep OF((z_streamp)); +ZEXTERN int ZEXPORT deflateResetKeep OF((z_streamp)); +#if defined(_WIN32) && !defined(Z_SOLO) +ZEXTERN gzFile ZEXPORT gzopen_w OF((const wchar_t *path, + const char *mode)); +#endif +#if defined(STDC) || defined(Z_HAVE_STDARG_H) +# ifndef Z_SOLO +ZEXTERN int ZEXPORTVA gzvprintf Z_ARG((gzFile file, + const char *format, + va_list va)); +# endif +#endif #ifdef __cplusplus } |