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version 1.1.1.2, 2013/10/14 07:51:14
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/* zlib.h -- interface of the 'zlib' general purpose compression library |
/* zlib.h -- interface of the 'zlib' general purpose compression library |
version 1.2.3, July 18th, 2005 | version 1.2.8, April 28th, 2013 |
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Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler | Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler |
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This software is provided 'as-is', without any express or implied |
This software is provided 'as-is', without any express or implied |
warranty. In no event will the authors be held liable for any damages |
warranty. In no event will the authors be held liable for any damages |
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The data format used by the zlib library is described by RFCs (Request for |
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 | Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950 |
(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format). | (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format). |
*/ |
*/ |
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#ifndef ZLIB_H |
#ifndef ZLIB_H |
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extern "C" { |
extern "C" { |
#endif |
#endif |
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#define ZLIB_VERSION "1.2.3" | #define ZLIB_VERSION "1.2.8" |
#define ZLIB_VERNUM 0x1230 | #define ZLIB_VERNUM 0x1280 |
| #define ZLIB_VER_MAJOR 1 |
| #define ZLIB_VER_MINOR 2 |
| #define ZLIB_VER_REVISION 8 |
| #define ZLIB_VER_SUBREVISION 0 |
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/* |
/* |
The 'zlib' compression library provides in-memory compression and | The 'zlib' compression library provides in-memory compression and |
decompression functions, including integrity checks of the uncompressed | decompression functions, including integrity checks of the uncompressed data. |
data. This version of the library supports only one compression method | This version of the library supports only one compression method (deflation) |
(deflation) but other algorithms will be added later and will have the same | but other algorithms will be added later and will have the same stream |
stream interface. | interface. |
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Compression can be done in a single step if the buffers are large | Compression can be done in a single step if the buffers are large enough, |
enough (for example if an input file is mmap'ed), or can be done by | or can be done by repeated calls of the compression function. In the latter |
repeated calls of the compression function. In the latter case, the | case, the application must provide more input and/or consume the output |
application must provide more input and/or consume the output | |
(providing more output space) before each call. |
(providing more output space) before each call. |
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The compressed data format used by default by the in-memory functions is | The compressed data format used by default by the in-memory functions is |
the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped |
the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped |
around a deflate stream, which is itself documented in RFC 1951. |
around a deflate stream, which is itself documented in RFC 1951. |
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The library also supports reading and writing files in gzip (.gz) format | The library also supports reading and writing files in gzip (.gz) format |
with an interface similar to that of stdio using the functions that start |
with an interface similar to that of stdio using the functions that start |
with "gz". The gzip format is different from the zlib format. gzip is a |
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. |
gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. |
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This library can optionally read and write gzip streams in memory as well. | This library can optionally read and write gzip streams in memory as well. |
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The zlib format was designed to be compact and fast for use in memory | 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- |
and on communications channels. The gzip format was designed for single- |
file compression on file systems, has a larger header than zlib to maintain |
file compression on file systems, has a larger header than zlib to maintain |
directory information, and uses a different, slower check method than zlib. |
directory information, and uses a different, slower check method than zlib. |
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The library does not install any signal handler. The decoder checks | The library does not install any signal handler. The decoder checks |
the consistency of the compressed data, so the library should never | the consistency of the compressed data, so the library should never crash |
crash even in case of corrupted input. | even in case of corrupted input. |
*/ |
*/ |
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typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); |
typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); |
Line 80 typedef void (*free_func) OF((voidpf opaque, voidpf
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Line 83 typedef void (*free_func) OF((voidpf opaque, voidpf
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struct internal_state; |
struct internal_state; |
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typedef struct z_stream_s { |
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 */ |
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 */ |
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Bytef *next_out; /* next output byte should be put there */ |
Bytef *next_out; /* next output byte should be put there */ |
uInt avail_out; /* remaining free space at next_out */ |
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 */ |
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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 */ |
struct internal_state FAR *state; /* not visible by applications */ |
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alloc_func zalloc; /* used to allocate the internal state */ |
alloc_func zalloc; /* used to allocate the internal state */ |
Line 126 typedef struct gz_header_s {
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Line 129 typedef struct gz_header_s {
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typedef gz_header FAR *gz_headerp; |
typedef gz_header FAR *gz_headerp; |
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/* |
/* |
The application must update next_in and avail_in when avail_in has | The application must update next_in and avail_in when avail_in has dropped |
dropped to zero. It must update next_out and avail_out when avail_out | to zero. It must update next_out and avail_out when avail_out has dropped |
has dropped to zero. The application must initialize zalloc, zfree and | to zero. The application must initialize zalloc, zfree and opaque before |
opaque before calling the init function. All other fields are set by the | calling the init function. All other fields are set by the compression |
compression library and must not be updated by the application. | library and must not be updated by the application. |
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The opaque value provided by the application will be passed as the first | The opaque value provided by the application will be passed as the first |
parameter for calls of zalloc and zfree. This can be useful for custom | parameter for calls of zalloc and zfree. This can be useful for custom |
memory management. The compression library attaches no meaning to the | memory management. The compression library attaches no meaning to the |
opaque value. |
opaque value. |
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zalloc must return Z_NULL if there is not enough memory for the object. | 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 |
If zlib is used in a multi-threaded application, zalloc and zfree must be |
thread safe. |
thread safe. |
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On 16-bit systems, the functions zalloc and zfree must be able to allocate | 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 | exactly 65536 bytes, but will not be required to allocate more than this if |
if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, | the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS, pointers |
pointers returned by zalloc for objects of exactly 65536 bytes *must* | returned by zalloc for objects of exactly 65536 bytes *must* have their |
have their offset normalized to zero. The default allocation function | offset normalized to zero. The default allocation function provided by this |
provided by this library ensures this (see zutil.c). To reduce memory | library ensures this (see zutil.c). To reduce memory requirements and avoid |
requirements and avoid any allocation of 64K objects, at the expense of | any allocation of 64K objects, at the expense of compression ratio, compile |
compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h). | the library with -DMAX_WBITS=14 (see zconf.h). |
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The fields total_in and total_out can be used for statistics or | The fields total_in and total_out can be used for statistics or progress |
progress reports. After compression, total_in holds the total size of | reports. After compression, total_in holds the total size of the |
the uncompressed data and may be saved for use in the decompressor | uncompressed data and may be saved for use in the decompressor (particularly |
(particularly if the decompressor wants to decompress everything in | if the decompressor wants to decompress everything in a single step). |
a single step). | |
*/ |
*/ |
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/* constants */ |
/* constants */ |
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#define Z_NO_FLUSH 0 |
#define Z_NO_FLUSH 0 |
#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */ | #define Z_PARTIAL_FLUSH 1 |
#define Z_SYNC_FLUSH 2 |
#define Z_SYNC_FLUSH 2 |
#define Z_FULL_FLUSH 3 |
#define Z_FULL_FLUSH 3 |
#define Z_FINISH 4 |
#define Z_FINISH 4 |
#define Z_BLOCK 5 |
#define Z_BLOCK 5 |
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#define Z_TREES 6 |
/* Allowed flush values; see deflate() and inflate() below for details */ |
/* Allowed flush values; see deflate() and inflate() below for details */ |
#define Z_INSERT_ONLY 6 | #define Z_INSERT_ONLY 7 |
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#define Z_OK 0 |
#define Z_OK 0 |
#define Z_STREAM_END 1 |
#define Z_STREAM_END 1 |
Line 177 typedef gz_header FAR *gz_headerp;
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Line 180 typedef gz_header FAR *gz_headerp;
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#define Z_MEM_ERROR (-4) |
#define Z_MEM_ERROR (-4) |
#define Z_BUF_ERROR (-5) |
#define Z_BUF_ERROR (-5) |
#define Z_VERSION_ERROR (-6) |
#define Z_VERSION_ERROR (-6) |
/* Return codes for the compression/decompression functions. Negative | /* Return codes for the compression/decompression functions. Negative values |
* values are errors, positive values are used for special but normal events. | * are errors, positive values are used for special but normal events. |
*/ |
*/ |
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#define Z_NO_COMPRESSION 0 |
#define Z_NO_COMPRESSION 0 |
Line 208 typedef gz_header FAR *gz_headerp;
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Line 211 typedef gz_header FAR *gz_headerp;
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#define zlib_version zlibVersion() |
#define zlib_version zlibVersion() |
/* for compatibility with versions < 1.0.2 */ |
/* for compatibility with versions < 1.0.2 */ |
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/* basic functions */ |
/* basic functions */ |
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ZEXTERN const char * ZEXPORT zlibVersion OF((void)); |
ZEXTERN const char * ZEXPORT zlibVersion OF((void)); |
/* The application can compare zlibVersion and ZLIB_VERSION for consistency. |
/* The application can compare zlibVersion and ZLIB_VERSION for consistency. |
If the first character differs, the library code actually used is | If the first character differs, the library code actually used is not |
not compatible with the zlib.h header file used by the application. | compatible with the zlib.h header file used by the application. This check |
This check is automatically made by deflateInit and inflateInit. | is automatically made by deflateInit and inflateInit. |
*/ |
*/ |
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/* |
/* |
ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); |
ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level)); |
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Initializes the internal stream state for compression. The fields | Initializes the internal stream state for compression. The fields |
zalloc, zfree and opaque must be initialized before by the caller. | zalloc, zfree and opaque must be initialized before by the caller. If |
If zalloc and zfree are set to Z_NULL, deflateInit updates them to | zalloc and zfree are set to Z_NULL, deflateInit updates them to use default |
use default allocation functions. | allocation functions. |
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The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: |
The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9: |
1 gives best speed, 9 gives best compression, 0 gives no compression at | 1 gives best speed, 9 gives best compression, 0 gives no compression at all |
all (the input data is simply copied a block at a time). | (the input data is simply copied a block at a time). Z_DEFAULT_COMPRESSION |
Z_DEFAULT_COMPRESSION requests a default compromise between speed and | requests a default compromise between speed and compression (currently |
compression (currently equivalent to level 6). | equivalent to level 6). |
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deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not | deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough |
enough memory, Z_STREAM_ERROR if level is not a valid compression level, | memory, Z_STREAM_ERROR if level is not a valid compression level, or |
Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible |
Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible |
with the version assumed by the caller (ZLIB_VERSION). | with the version assumed by the caller (ZLIB_VERSION). msg is set to null |
msg is set to null if there is no error message. deflateInit does not | if there is no error message. deflateInit does not perform any compression: |
perform any compression: this will be done by deflate(). | this will be done by deflate(). |
*/ |
*/ |
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ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); |
ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush)); |
/* |
/* |
deflate compresses as much data as possible, and stops when the input |
deflate compresses as much data as possible, and stops when the input |
buffer becomes empty or the output buffer becomes full. It may introduce some | buffer becomes empty or the output buffer becomes full. It may introduce |
output latency (reading input without producing any output) except when | some output latency (reading input without producing any output) except when |
forced to flush. |
forced to flush. |
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The detailed semantics are as follows. deflate performs one or both of the | The detailed semantics are as follows. deflate performs one or both of the |
following actions: |
following actions: |
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- Compress more input starting at next_in and update next_in and avail_in |
- Compress 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 | accordingly. If not all input can be processed (because there is not |
enough room in the output buffer), next_in and avail_in are updated and |
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(). |
processing will resume at this point for the next call of deflate(). |
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- Provide more output starting at next_out and update next_out and avail_out |
- Provide 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. | accordingly. This action is forced if the parameter flush is non zero. |
Forcing flush frequently degrades the compression ratio, so this parameter |
Forcing flush frequently degrades the compression ratio, so this parameter |
should be set only when necessary (in interactive applications). | should be set only when necessary (in interactive applications). Some |
Some output may be provided even if flush is not set. | output may be provided even if flush is not set. |
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Before the call of deflate(), the application should ensure that at least | 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 | one of the actions is possible, by providing more input and/or consuming more |
more output, and updating avail_in or avail_out accordingly; avail_out | output, and updating avail_in or avail_out accordingly; avail_out should |
should never be zero before the call. The application can consume the | never be zero before the call. The application can consume the compressed |
compressed output when it wants, for example when the output buffer is full | output when it wants, for example when the output buffer is full (avail_out |
(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK | == 0), or after each call of deflate(). If deflate returns Z_OK and with |
and with zero avail_out, it must be called again after making room in the | zero avail_out, it must be called again after making room in the output |
output buffer because there might be more output pending. | buffer because there might be more output pending. |
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Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to |
Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to |
decide how much data to accumualte before producing output, in order to | decide how much data to accumulate before producing output, in order to |
maximize compression. |
maximize compression. |
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If the parameter flush is set to Z_SYNC_FLUSH, all pending output is |
If the parameter flush is set to Z_SYNC_FLUSH, all pending output is |
flushed to the output buffer and the output is aligned on a byte boundary, so |
flushed to the output buffer and the output is aligned on a byte boundary, so |
that the decompressor can get all input data available so far. (In particular | that the decompressor can get all input data available so far. (In |
avail_in is zero after the call if enough output space has been provided | particular avail_in is zero after the call if enough output space has been |
before the call.) Flushing may degrade compression for some compression | provided before the call.) Flushing may degrade compression for some |
algorithms and so it should be used only when necessary. | compression algorithms and so it should be used only when necessary. This |
| completes the current deflate block and follows it with an empty stored block |
| that is three bits plus filler bits to the next byte, followed by four bytes |
| (00 00 ff ff). |
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If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the |
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output buffer, but the output is not aligned to a byte boundary. All of the |
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input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. |
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This completes the current deflate block and follows it with an empty fixed |
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codes block that is 10 bits long. This assures that enough bytes are output |
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in order for the decompressor to finish the block before the empty fixed code |
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block. |
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If flush is set to Z_BLOCK, a deflate block is completed and emitted, as |
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for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to |
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seven bits of the current block are held to be written as the next byte after |
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the next deflate block is completed. In this case, the decompressor may not |
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be provided enough bits at this point in order to complete decompression of |
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the data provided so far to the compressor. It may need to wait for the next |
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block to be emitted. This is for advanced applications that need to control |
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the emission of deflate blocks. |
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If flush is set to Z_FULL_FLUSH, all output is flushed as with |
If flush is set to Z_FULL_FLUSH, all output is flushed as with |
Z_SYNC_FLUSH, and the compression state is reset so that decompression can |
Z_SYNC_FLUSH, and the compression state is reset so that decompression can |
restart from this point if previous compressed data has been damaged or if |
restart from this point if previous compressed data has been damaged or if |
random access is desired. Using Z_FULL_FLUSH too often can seriously degrade | random access is desired. Using Z_FULL_FLUSH too often can seriously degrade |
compression. |
compression. |
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If deflate returns with avail_out == 0, this function must be called again |
If deflate returns with avail_out == 0, this function must be called again |
with the same value of the flush parameter and more output space (updated |
with the same value of the flush parameter and more output space (updated |
avail_out), until the flush is complete (deflate returns with non-zero |
avail_out), until the flush is complete (deflate returns with non-zero |
avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that | avail_out). In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that |
avail_out is greater than six to avoid repeated flush markers due to |
avail_out is greater than six to avoid repeated flush markers due to |
avail_out == 0 on return. |
avail_out == 0 on return. |
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If the parameter flush is set to Z_FINISH, pending input is processed, |
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 | pending output is flushed and deflate returns with Z_STREAM_END if there was |
was enough output space; if deflate returns with Z_OK, this function must be | 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 |
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 | 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 | deflate has returned Z_STREAM_END, the only possible operations on the stream |
stream are deflateReset or deflateEnd. | are deflateReset or deflateEnd. |
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Z_FINISH can be used immediately after deflateInit if all the compression |
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 | is to be done in a single step. In this case, avail_out must be at least the |
the value returned by deflateBound (see below). If deflate does not return | value returned by deflateBound (see below). Then deflate is guaranteed to |
Z_STREAM_END, then it must be called again as described above. | 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. |
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deflate() sets strm->adler to the adler32 checksum of all input read |
deflate() sets strm->adler to the adler32 checksum of all input read |
so far (that is, total_in bytes). |
so far (that is, total_in bytes). |
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deflate() may update strm->data_type if it can make a good guess about |
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 | 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 | binary. This field is only for information purposes and does not affect the |
the compression algorithm in any manner. | compression algorithm in any manner. |
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deflate() returns Z_OK if some progress has been made (more input |
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 |
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 |
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 |
Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example |
if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible | 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 | (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 |
fatal, and deflate() can be called again with more input and more output |
space to continue compressing. |
space to continue compressing. |
*/ |
*/ |
Line 329 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int fl
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Line 354 ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int fl
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ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); |
ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm)); |
/* |
/* |
All dynamically allocated data structures for this stream are freed. |
All dynamically allocated data structures for this stream are freed. |
This function discards any unprocessed input and does not flush any | This function discards any unprocessed input and does not flush any pending |
pending output. | output. |
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deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the |
deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the |
stream state was inconsistent, Z_DATA_ERROR if the stream was freed |
stream state was inconsistent, Z_DATA_ERROR if the stream was freed |
prematurely (some input or output was discarded). In the error case, | prematurely (some input or output was discarded). In the error case, msg |
msg may be set but then points to a static string (which must not be | may be set but then points to a static string (which must not be |
deallocated). |
deallocated). |
*/ |
*/ |
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Line 343 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
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Line 368 ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
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/* |
/* |
ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); |
ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm)); |
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Initializes the internal stream state for decompression. The fields | Initializes the internal stream state for decompression. The fields |
next_in, avail_in, zalloc, zfree and opaque must be initialized before by |
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 | the caller. If next_in is not Z_NULL and avail_in is large enough (the |
value depends on the compression method), inflateInit determines the | exact value depends on the compression method), inflateInit determines the |
compression method from the zlib header and allocates all data structures |
compression method from the zlib header and allocates all data structures |
accordingly; otherwise the allocation will be deferred to the first call of |
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 |
inflate. If zalloc and zfree are set to Z_NULL, inflateInit updates them to |
Line 354 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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Line 379 ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));
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inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough |
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 |
memory, Z_VERSION_ERROR if the zlib library version is incompatible with the |
version assumed by the caller. msg is set to null if there is no error | version assumed by the caller, or Z_STREAM_ERROR if the parameters are |
message. inflateInit does not perform any decompression apart from reading | invalid, such as a null pointer to the structure. msg is set to null if |
the zlib header if present: this will be done by inflate(). (So next_in and | there is no error message. inflateInit does not perform any decompression |
avail_in may be modified, but next_out and avail_out are unchanged.) | 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. |
*/ |
*/ |
|
|
|
|
ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); |
ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush)); |
/* |
/* |
inflate decompresses as much data as possible, and stops when the input |
inflate decompresses as much data as possible, and stops when the input |
buffer becomes empty or the output buffer becomes full. It may introduce | buffer becomes empty or the output buffer becomes full. It may introduce |
some output latency (reading input without producing any output) except when |
some output latency (reading input without producing any output) except when |
forced to flush. |
forced to flush. |
|
|
The detailed semantics are as follows. inflate performs one or both of the | The detailed semantics are as follows. inflate performs one or both of the |
following actions: |
following actions: |
|
|
- Decompress more input starting at next_in and update next_in and avail_in |
- 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 | accordingly. If not all input can be processed (because there is not |
enough room in the output buffer), next_in is updated and processing | enough room in the output buffer), next_in is updated and processing will |
will resume at this point for the next call of inflate(). | resume at this point for the next call of inflate(). |
|
|
- Provide more output starting at next_out and update next_out and avail_out |
- Provide more output starting at next_out and update next_out and avail_out |
accordingly. inflate() provides as much output as possible, until there | accordingly. inflate() provides as much output as possible, until there is |
is no more input data or no more space in the output buffer (see below | no more input data or no more space in the output buffer (see below about |
about the flush parameter). | the flush parameter). |
|
|
Before the call of inflate(), the application should ensure that at least | 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 | one of the actions is possible, by providing more input and/or consuming more |
more output, and updating the next_* and avail_* values accordingly. | output, and updating the next_* and avail_* values accordingly. The |
The application can consume the uncompressed output when it wants, for | application can consume the uncompressed output when it wants, for example |
example when the output buffer is full (avail_out == 0), or after each | when the output buffer is full (avail_out == 0), or after each call of |
call of inflate(). If inflate returns Z_OK and with zero avail_out, it | inflate(). If inflate returns Z_OK and with zero avail_out, it must be |
must be called again after making room in the output buffer because there | called again after making room in the output buffer because there might be |
might be more output pending. | more output pending. |
|
|
The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, | The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH, |
Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much | Z_BLOCK, or Z_TREES. Z_SYNC_FLUSH requests that inflate() flush as much |
output as possible to the output buffer. Z_BLOCK requests that inflate() stop | output as possible to the output buffer. Z_BLOCK requests that inflate() |
if and when it gets to the next deflate block boundary. When decoding the | stop if and when it gets to the next deflate block boundary. When decoding |
zlib or gzip format, this will cause inflate() to return immediately after | the zlib or gzip format, this will cause inflate() to return immediately |
the header and before the first block. When doing a raw inflate, inflate() | after the header and before the first block. When doing a raw inflate, |
will go ahead and process the first block, and will return when it gets to | inflate() will go ahead and process the first block, and will return when it |
the end of that block, or when it runs out of data. | 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. |
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 |
Also to assist in this, on return inflate() will set strm->data_type to the |
number of unused bits in the last byte taken from strm->next_in, plus 64 | number of unused bits in the last byte taken from strm->next_in, plus 64 if |
if inflate() is currently decoding the last block in the deflate stream, | inflate() is currently decoding the last block in the deflate stream, plus |
plus 128 if inflate() returned immediately after decoding an end-of-block | 128 if inflate() returned immediately after decoding an end-of-block code or |
code or decoding the complete header up to just before the first byte of the | decoding the complete header up to just before the first byte of the deflate |
deflate stream. The end-of-block will not be indicated until all of the | stream. The end-of-block will not be indicated until all of the uncompressed |
uncompressed data from that block has been written to strm->next_out. The | data from that block has been written to strm->next_out. The number of |
number of unused bits may in general be greater than seven, except when | unused bits may in general be greater than seven, except when bit 7 of |
bit 7 of data_type is set, in which case the number of unused bits will be | data_type is set, in which case the number of unused bits will be less than |
less than eight. | eight. data_type is set as noted here every time inflate() returns for all |
| flush options, and so can be used to determine the amount of currently |
| consumed input in bits. |
|
|
|
The Z_TREES option behaves as Z_BLOCK does, but it also returns when the |
|
end of each deflate block header is reached, before any actual data in that |
|
block is decoded. This allows the caller to determine the length of the |
|
deflate block header for later use in random access within a deflate block. |
|
256 is added to the value of strm->data_type when inflate() returns |
|
immediately after reaching the end of the deflate block header. |
|
|
inflate() should normally be called until it returns Z_STREAM_END or an |
inflate() should normally be called until it returns Z_STREAM_END or an |
error. However if all decompression is to be performed in a single step | error. However if all decompression is to be performed in a single step (a |
(a single call of inflate), the parameter flush should be set to | single call of inflate), the parameter flush should be set to Z_FINISH. In |
Z_FINISH. In this case all pending input is processed and all pending | this case all pending input is processed and all pending output is flushed; |
output is flushed; avail_out must be large enough to hold all the | avail_out must be large enough to hold all of the uncompressed data for the |
uncompressed data. (The size of the uncompressed data may have been saved | operation to complete. (The size of the uncompressed data may have been |
by the compressor for this purpose.) The next operation on this stream must | saved by the compressor for this purpose.) The use of Z_FINISH is not |
be inflateEnd to deallocate the decompression state. The use of Z_FINISH | required to perform an inflation in one step. However it may be used to |
is never required, but can be used to inform inflate that a faster approach | inform inflate that a faster approach can be used for the single inflate() |
may be used for the single inflate() call. | 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 |
In this implementation, inflate() always flushes as much output as |
possible to the output buffer, and always uses the faster approach on the |
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 | first call. So the effects of the flush parameter in this implementation are |
is on the return value of inflate(), as noted below, or when it returns early | on the return value of inflate() as noted below, when inflate() returns early |
because Z_BLOCK is used. | 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 |
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 |
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 |
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 adler32 |
checksum is equal to that saved by the compressor and returns Z_STREAM_END |
checksum is equal to that saved by the compressor and returns Z_STREAM_END |
only if the checksum is correct. |
only if the checksum is correct. |
|
|
inflate() will decompress and check either zlib-wrapped or gzip-wrapped | inflate() can decompress and check either zlib-wrapped or gzip-wrapped |
deflate data. The header type is detected automatically. Any information | deflate data. The header type is detected automatically, if requested when |
contained in the gzip header is not retained, so applications that need that | initializing with inflateInit2(). Any information contained in the gzip |
information should instead use raw inflate, see inflateInit2() below, or | header is not retained, so applications that need that information should |
inflateBack() and perform their own processing of the gzip header and | instead use raw inflate, see inflateInit2() below, or inflateBack() and |
trailer. | perform their own processing of the gzip header and trailer. When processing |
| gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output |
| producted so far. The CRC-32 is checked against the gzip trailer. |
|
|
inflate() returns Z_OK if some progress has been made (more input processed |
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 |
or more output produced), Z_STREAM_END if the end of the compressed data has |
Line 450 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int fl
|
Line 496 ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int fl
|
preset dictionary is needed at this point, Z_DATA_ERROR if the input data was |
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 |
corrupted (input stream not conforming to the zlib format or incorrect check |
value), Z_STREAM_ERROR if the stream structure was inconsistent (for example |
value), Z_STREAM_ERROR if the stream structure was inconsistent (for example |
if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory, | 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 |
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 | 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 |
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 | continue decompressing. If Z_DATA_ERROR is returned, the application may |
call inflateSync() to look for a good compression block if a partial recovery | then call inflateSync() to look for a good compression block if a partial |
of the data is desired. | recovery of the data is desired. |
*/ |
*/ |
|
|
|
|
ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); |
ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm)); |
/* |
/* |
All dynamically allocated data structures for this stream are freed. |
All dynamically allocated data structures for this stream are freed. |
This function discards any unprocessed input and does not flush any | This function discards any unprocessed input and does not flush any pending |
pending output. | output. |
|
|
inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state |
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 | was inconsistent. In the error case, msg may be set but then points to a |
static string (which must not be deallocated). |
static string (which must not be deallocated). |
*/ |
*/ |
|
|
|
|
/* Advanced functions */ |
/* Advanced functions */ |
|
|
/* |
/* |
Line 485 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
|
Line 532 ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
|
int memLevel, |
int memLevel, |
int strategy)); |
int strategy)); |
|
|
This is another version of deflateInit with more compression options. The | This is another version of deflateInit with more compression options. The |
fields next_in, zalloc, zfree and opaque must be initialized before by | fields next_in, zalloc, zfree and opaque must be initialized before by the |
the caller. | caller. |
|
|
The method parameter is the compression method. It must be Z_DEFLATED in | The method parameter is the compression method. It must be Z_DEFLATED in |
this version of the library. |
this version of the library. |
|
|
The windowBits parameter is the base two logarithm of the window size |
The windowBits parameter is the base two logarithm of the window size |
(the size of the history buffer). It should be in the range 8..15 for this | (the size of the history buffer). It should be in the range 8..15 for this |
version of the library. Larger values of this parameter result in better | version of the library. Larger values of this parameter result in better |
compression at the expense of memory usage. The default value is 15 if | compression at the expense of memory usage. The default value is 15 if |
deflateInit is used instead. |
deflateInit is used instead. |
|
|
windowBits can also be -8..-15 for raw deflate. In this case, -windowBits | windowBits can also be -8..-15 for raw deflate. In this case, -windowBits |
determines the window size. deflate() will then generate raw deflate data | 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 an adler32 check value. |
|
|
windowBits can also be greater than 15 for optional gzip encoding. Add | 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 |
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 | 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), | file name, no extra data, no comment, no modification time (set to zero), no |
no header crc, and the operating system will be set to 255 (unknown). If a | 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. |
gzip stream is being written, strm->adler is a crc32 instead of an adler32. |
|
|
The memLevel parameter specifies how much memory should be allocated |
The memLevel parameter specifies how much memory should be allocated |
for the internal compression state. memLevel=1 uses minimum memory but | for the internal compression state. memLevel=1 uses minimum memory but is |
is slow and reduces compression ratio; memLevel=9 uses maximum memory | slow and reduces compression ratio; memLevel=9 uses maximum memory for |
for optimal speed. The default value is 8. See zconf.h for total memory | optimal speed. The default value is 8. See zconf.h for total memory usage |
usage as a function of windowBits and memLevel. | as a function of windowBits and memLevel. |
|
|
The strategy parameter is used to tune the compression algorithm. Use the | The strategy parameter is used to tune the compression algorithm. Use the |
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a |
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a |
filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no |
filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no |
string match), or Z_RLE to limit match distances to one (run-length |
string match), or Z_RLE to limit match distances to one (run-length |
encoding). Filtered data consists mostly of small values with a somewhat | encoding). Filtered data consists mostly of small values with a somewhat |
random distribution. In this case, the compression algorithm is tuned to | random distribution. In this case, the compression algorithm is tuned to |
compress them better. The effect of Z_FILTERED is to force more Huffman | compress them better. The effect of Z_FILTERED is to force more Huffman |
coding and less string matching; it is somewhat intermediate between |
coding and less string matching; it is somewhat intermediate between |
Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as | Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as |
Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy | fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data. The |
parameter only affects the compression ratio but not the correctness of the | strategy parameter only affects the compression ratio but not the |
compressed output even if it is not set appropriately. Z_FIXED prevents the | correctness of the compressed output even if it is not set appropriately. |
use of dynamic Huffman codes, allowing for a simpler decoder for special | Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler |
applications. | decoder for special applications. |
|
|
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough | deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid | memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid |
method). msg is set to null if there is no error message. deflateInit2 does | method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is |
not perform any compression: this will be done by deflate(). | incompatible with the version assumed by the caller (ZLIB_VERSION). msg is |
| set to null if there is no error message. deflateInit2 does not perform any |
| compression: this will be done by deflate(). |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, |
ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm, |
Line 541 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp
|
Line 590 ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp
|
uInt dictLength)); |
uInt dictLength)); |
/* |
/* |
Initializes the compression dictionary from the given byte sequence |
Initializes the compression dictionary from the given byte sequence |
without producing any compressed output. This function must be called | without producing any compressed output. When using the zlib format, this |
immediately after deflateInit, deflateInit2 or deflateReset, before any | function must be called immediately after deflateInit, deflateInit2 or |
call of deflate. The compressor and decompressor must use exactly the same | deflateReset, and before any call of deflate. When doing raw deflate, this |
dictionary (see inflateSetDictionary). | 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 |
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 |
to be encountered later in the data to be compressed, with the most commonly |
used strings preferably put towards the end of the dictionary. Using a | used strings preferably put towards the end of the dictionary. Using a |
dictionary is most useful when the data to be compressed is short and can be |
dictionary is most useful when the data to be compressed is short and can be |
predicted with good accuracy; the data can then be compressed better than |
predicted with good accuracy; the data can then be compressed better than |
with the default empty dictionary. |
with the default empty dictionary. |
|
|
Depending on the size of the compression data structures selected by |
Depending on the size of the compression data structures selected by |
deflateInit or deflateInit2, a part of the dictionary may in effect be |
deflateInit or deflateInit2, a part of the dictionary may in effect be |
discarded, for example if the dictionary is larger than the window size in | discarded, for example if the dictionary is larger than the window size |
deflate or deflate2. Thus the strings most likely to be useful should be | provided in deflateInit or deflateInit2. Thus the strings most likely to be |
put at the end of the dictionary, not at the front. In addition, the | useful should be put at the end of the dictionary, not at the front. In |
current implementation of deflate will use at most the window size minus | addition, the current implementation of deflate will use at most the window |
262 bytes of the provided dictionary. | 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 adler32 value |
of the dictionary; the decompressor may later use this value to determine |
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 adler32 value |
applies to the whole dictionary even if only a subset of the dictionary is |
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 |
actually used by the compressor.) If a raw deflate was requested, then the |
adler32 value is not computed and strm->adler is not set. |
adler32 value is not computed and strm->adler is not set. |
|
|
deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a |
deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a |
parameter is invalid (such as NULL dictionary) or the stream state is | 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 |
inconsistent (for example if deflate has already been called for this stream |
or if the compression method is bsort). deflateSetDictionary does not | or if not at a block boundary for raw deflate). deflateSetDictionary does |
perform any compression: this will be done by deflate(). | not perform any compression: this will be done by deflate(). |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, |
ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest, |
Line 582 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
|
Line 636 ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
|
|
|
This function can be useful when several compression strategies will be |
This function can be useful when several compression strategies will be |
tried, for example when there are several ways of pre-processing the input |
tried, for example when there are several ways of pre-processing the input |
data with a filter. The streams that will be discarded should then be freed | data with a filter. The streams that will be discarded should then be freed |
by calling deflateEnd. Note that deflateCopy duplicates the internal |
by calling deflateEnd. Note that deflateCopy duplicates the internal |
compression state which can be quite large, so this strategy is slow and | compression state which can be quite large, so this strategy is slow and can |
can consume lots of memory. | consume lots of memory. |
|
|
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not |
deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not |
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent |
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent |
(such as zalloc being NULL). msg is left unchanged in both source and | (such as zalloc being Z_NULL). msg is left unchanged in both source and |
destination. |
destination. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); |
ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm)); |
/* |
/* |
This function is equivalent to deflateEnd followed by deflateInit, |
This function is equivalent to deflateEnd followed by deflateInit, |
but does not free and reallocate all the internal compression state. | but does not free and reallocate all the internal compression state. The |
The stream will keep the same compression level and any other attributes | stream will keep the same compression level and any other attributes that |
that may have been set by deflateInit2. | may have been set by deflateInit2. |
|
|
deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source | deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
stream state was inconsistent (such as zalloc or state being NULL). | stream state was inconsistent (such as zalloc or state being Z_NULL). |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, |
ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm, |
Line 611 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
|
Line 665 ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
|
Dynamically update the compression level and compression strategy. The |
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 |
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 | to switch to a different kind of input data requiring a different strategy. |
strategy. If the compression level is changed, the input available so far | If the compression level is changed, the input available so far is |
is compressed with the old level (and may be flushed); the new level will | compressed with the old level (and may be flushed); the new level will take |
take effect only at the next call of deflate(). | effect only at the next call of deflate(). |
|
|
Before the call of deflateParams, the stream state must be set as for |
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 | a call of deflate(), since the currently available input may have to be |
be compressed and flushed. In particular, strm->avail_out must be non-zero. | compressed and flushed. In particular, strm->avail_out must be non-zero. |
|
|
deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source |
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 | stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR if |
if strm->avail_out was zero. | strm->avail_out was zero. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, |
ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm, |
Line 646 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
|
Line 700 ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
|
uLong sourceLen)); |
uLong sourceLen)); |
/* |
/* |
deflateBound() returns an upper bound on the compressed size after |
deflateBound() returns an upper bound on the compressed size after |
deflation of sourceLen bytes. It must be called after deflateInit() | deflation of sourceLen bytes. It must be called after deflateInit() or |
or deflateInit2(). This would be used to allocate an output buffer | deflateInit2(), and after deflateSetHeader(), if used. This would be used |
for deflation in a single pass, and so would be called before deflate(). | to allocate an output buffer for deflation in a single pass, and so would be |
| 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, |
ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, |
int bits, |
int bits, |
int value)); |
int value)); |
/* |
/* |
deflatePrime() inserts bits in the deflate output stream. The intent |
deflatePrime() inserts bits in the deflate output stream. The intent |
is that this function is used to start off the deflate output with the | is that this function is used to start off the deflate output with the bits |
bits leftover from a previous deflate stream when appending to it. As such, | leftover from a previous deflate stream when appending to it. As such, this |
this function can only be used for raw deflate, and must be used before the | function can only be used for raw deflate, and must be used before the first |
first deflate() call after a deflateInit2() or deflateReset(). bits must be | deflate() call after a deflateInit2() or deflateReset(). bits must be less |
less than or equal to 16, and that many of the least significant bits of | than or equal to 16, and that many of the least significant bits of value |
value will be inserted in the output. | will be inserted in the output. |
|
|
deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source | deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough |
stream state was inconsistent. | 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, |
ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, |
gz_headerp head)); |
gz_headerp head)); |
/* |
/* |
deflateSetHeader() provides gzip header information for when a gzip | deflateSetHeader() provides gzip header information for when a gzip |
stream is requested by deflateInit2(). deflateSetHeader() may be called |
stream is requested by deflateInit2(). deflateSetHeader() may be called |
after deflateInit2() or deflateReset() and before the first call of |
after deflateInit2() or deflateReset() and before the first call of |
deflate(). The text, time, os, extra field, name, and comment information |
deflate(). The text, time, os, extra field, name, and comment information |
Line 683 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp str
|
Line 759 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp str
|
1.3.x) do not support header crc's, and will report that it is a "multi-part |
1.3.x) do not support header crc's, and will report that it is a "multi-part |
gzip file" and give up. |
gzip file" and give up. |
|
|
If deflateSetHeader is not used, the default gzip header has text false, | If deflateSetHeader is not used, the default gzip header has text false, |
the time set to zero, and os set to 255, with no extra, name, or comment |
the time set to zero, and os set to 255, with no extra, name, or comment |
fields. The gzip header is returned to the default state by deflateReset(). |
fields. The gzip header is returned to the default state by deflateReset(). |
|
|
deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source | deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source |
stream state was inconsistent. |
stream state was inconsistent. |
*/ |
*/ |
|
|
Line 695 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp str
|
Line 771 ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp str
|
ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, |
ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm, |
int windowBits)); |
int windowBits)); |
|
|
This is another version of inflateInit with an extra parameter. The | This is another version of inflateInit with an extra parameter. The |
fields next_in, avail_in, zalloc, zfree and opaque must be initialized |
fields next_in, avail_in, zalloc, zfree and opaque must be initialized |
before by the caller. |
before by the caller. |
|
|
The windowBits parameter is the base two logarithm of the maximum window |
The windowBits parameter is the base two logarithm of the maximum window |
size (the size of the history buffer). It should be in the range 8..15 for |
size (the size of the history buffer). It should be in the range 8..15 for |
this version of the library. The default value is 15 if inflateInit is used | this version of the library. The default value is 15 if inflateInit is used |
instead. windowBits must be greater than or equal to the windowBits value | instead. windowBits must be greater than or equal to the windowBits value |
provided to deflateInit2() while compressing, or it must be equal to 15 if |
provided to deflateInit2() while compressing, or it must be equal to 15 if |
deflateInit2() was not used. If a compressed stream with a larger window | deflateInit2() was not used. If a compressed stream with a larger window |
size is given as input, inflate() will return with the error code |
size is given as input, inflate() will return with the error code |
Z_DATA_ERROR instead of trying to allocate a larger window. |
Z_DATA_ERROR instead of trying to allocate a larger window. |
|
|
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits | windowBits can also be zero to request that inflate use the window size in |
determines the window size. inflate() will then process raw deflate data, | the zlib header of the compressed stream. |
| |
| windowBits can also be -8..-15 for raw inflate. In this case, -windowBits |
| determines the window size. inflate() will then process raw deflate data, |
not looking for a zlib or gzip header, not generating a check value, and not |
not looking for a zlib or gzip header, not generating a check value, and not |
looking for any check values for comparison at the end of the stream. This | looking for any check values for comparison at the end of the stream. This |
is for use with other formats that use the deflate compressed data format |
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 | 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 |
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 adler32 or a crc32 be applied to |
the uncompressed data as is done in the zlib, gzip, and zip formats. For |
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 | 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. |
above on the use in deflateInit2() applies to the magnitude of windowBits. |
|
|
windowBits can also be greater than 15 for optional gzip decoding. Add | windowBits can also be greater than 15 for optional gzip decoding. Add |
32 to windowBits to enable zlib and gzip decoding with automatic header |
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 |
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 | return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is a |
a crc32 instead of an adler32. | crc32 instead of an adler32. |
|
|
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg | memory, Z_VERSION_ERROR if the zlib library version is incompatible with the |
is set to null if there is no error message. inflateInit2 does not perform | version assumed by the caller, or Z_STREAM_ERROR if the parameters are |
any decompression apart from reading the zlib header if present: this will | invalid, such as a null pointer to the structure. msg is set to null if |
be done by inflate(). (So next_in and avail_in may be modified, but next_out | there is no error message. inflateInit2 does not perform any decompression |
and avail_out are unchanged.) | 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 inflateInit2() does not process any header information -- that is |
| deferred until inflate() is called. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, |
ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, |
Line 739 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp
|
Line 822 ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp
|
uInt dictLength)); |
uInt dictLength)); |
/* |
/* |
Initializes the decompression dictionary from the given uncompressed byte |
Initializes the decompression dictionary from the given uncompressed byte |
sequence. This function must be called immediately after a call of inflate, | 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 | 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 adler32 value returned by that call of inflate. |
The compressor and decompressor must use exactly the same dictionary (see |
The compressor and decompressor must use exactly the same dictionary (see |
deflateSetDictionary). For raw inflate, this function can be called | deflateSetDictionary). For raw inflate, this function can be called at any |
immediately after inflateInit2() or inflateReset() and before any call of | time to set the dictionary. If the provided dictionary is smaller than the |
inflate() to set the dictionary. The application must insure that the | window and there is already data in the window, then the provided dictionary |
dictionary that was used for compression is provided. | 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 |
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a |
parameter is invalid (such as NULL dictionary) or the stream state is | 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 |
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the |
expected one (incorrect adler32 value). inflateSetDictionary does not | expected one (incorrect adler32 value). inflateSetDictionary does not |
perform any decompression: this will be done by subsequent calls of |
perform any decompression: this will be done by subsequent calls of |
inflate(). |
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. |
|
Similary, 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)); |
ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); |
/* |
/* |
Skips invalid compressed data until a full flush point (see above the | Skips invalid compressed data until a possible full flush point (see above |
description of deflate with Z_FULL_FLUSH) can be found, or until all | for the description of deflate with Z_FULL_FLUSH) can be found, or until all |
available input is skipped. No output is provided. | available input is skipped. No output is provided. |
|
|
inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR | inflateSync searches for a 00 00 FF FF pattern in the compressed data. |
if no more input was provided, Z_DATA_ERROR if no flush point has been found, | All full flush points have this pattern, but not all occurrences of this |
or Z_STREAM_ERROR if the stream structure was inconsistent. In the success | pattern are full flush points. |
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 | inflateSync returns Z_OK if a possible full flush point has been found, |
application may repeatedly call inflateSync, providing more input each time, | Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point |
until success or end of the input data. | 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, |
ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest, |
Line 783 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
|
Line 886 ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
|
|
|
inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not |
inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not |
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent |
enough memory, Z_STREAM_ERROR if the source stream state was inconsistent |
(such as zalloc being NULL). msg is left unchanged in both source and | (such as zalloc being Z_NULL). msg is left unchanged in both source and |
destination. |
destination. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); |
ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm)); |
/* |
/* |
This function is equivalent to inflateEnd followed by inflateInit, |
This function is equivalent to inflateEnd followed by inflateInit, |
but does not free and reallocate all the internal decompression state. | but does not free and reallocate all the internal decompression state. The |
The stream will keep attributes that may have been set by inflateInit2. | stream will keep attributes that may have been set by inflateInit2. |
|
|
inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source | inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source |
stream state was inconsistent (such as zalloc or state being NULL). | stream state was inconsistent (such as zalloc or state being Z_NULL). |
*/ |
*/ |
|
|
|
ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, |
|
int windowBits)); |
|
/* |
|
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. |
|
|
|
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 |
|
the windowBits parameter is invalid. |
|
*/ |
|
|
ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, |
ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, |
int bits, |
int bits, |
int value)); |
int value)); |
/* |
/* |
This function inserts bits in the inflate input stream. The intent is |
This function inserts bits in the inflate input stream. The intent is |
that this function is used to start inflating at a bit position in the | that this function is used to start inflating at a bit position in the |
middle of a byte. The provided bits will be used before any bytes are used | middle of a byte. The provided bits will be used before any bytes are used |
from next_in. This function should only be used with raw inflate, and | from next_in. This function should only be used with raw inflate, and |
should be used before the first inflate() call after inflateInit2() or | should be used before the first inflate() call after inflateInit2() or |
inflateReset(). bits must be less than or equal to 16, and that many of the | inflateReset(). bits must be less than or equal to 16, and that many of the |
least significant bits of value will be inserted in the input. | least significant bits of value will be inserted in the input. |
|
|
inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source | If bits is negative, then the input stream bit buffer is emptied. Then |
| inflatePrime() can be called again to put bits in the buffer. This is used |
| to clear out bits leftover after feeding inflate a block description prior |
| to feeding inflate codes. |
| |
| inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source |
stream state was inconsistent. |
stream state was inconsistent. |
*/ |
*/ |
|
|
|
ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); |
|
/* |
|
This function returns two values, one in the lower 16 bits of the return |
|
value, and the other in the remaining upper bits, obtained by shifting the |
|
return value down 16 bits. If the upper value is -1 and the lower value is |
|
zero, then inflate() is currently decoding information outside of a block. |
|
If the upper value is -1 and the lower value is non-zero, then inflate is in |
|
the middle of a stored block, with the lower value equaling the number of |
|
bytes from the input remaining to copy. If the upper value is not -1, then |
|
it is the number of bits back from the current bit position in the input of |
|
the code (literal or length/distance pair) currently being processed. In |
|
that case the lower value is the number of bytes already emitted for that |
|
code. |
|
|
|
A code is being processed if inflate is waiting for more input to complete |
|
decoding of the code, or if it has completed decoding but is waiting for |
|
more output space to write the literal or match data. |
|
|
|
inflateMark() is used to mark locations in the input data for random |
|
access, which may be at bit positions, and to note those cases where the |
|
output of a code may span boundaries of random access blocks. The current |
|
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 |
|
source stream state was inconsistent. |
|
*/ |
|
|
ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, |
ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, |
gz_headerp head)); |
gz_headerp head)); |
/* |
/* |
inflateGetHeader() requests that gzip header information be stored in the | inflateGetHeader() requests that gzip header information be stored in the |
provided gz_header structure. inflateGetHeader() may be called after |
provided gz_header structure. inflateGetHeader() may be called after |
inflateInit2() or inflateReset(), and before the first call of inflate(). |
inflateInit2() or inflateReset(), and before the first call of inflate(). |
As inflate() processes the gzip stream, head->done is zero until the header |
As inflate() processes the gzip stream, head->done is zero until the header |
is completed, at which time head->done is set to one. If a zlib stream is |
is completed, at which time head->done is set to one. If a zlib stream is |
being decoded, then head->done is set to -1 to indicate that there will be |
being decoded, then head->done is set to -1 to indicate that there will be |
no gzip header information forthcoming. Note that Z_BLOCK can be used to | no gzip header information forthcoming. Note that Z_BLOCK or Z_TREES can be |
force inflate() to return immediately after header processing is complete | used to force inflate() to return immediately after header processing is |
and before any actual data is decompressed. | complete and before any actual data is decompressed. |
|
|
The text, time, xflags, and os fields are filled in with the gzip header | The text, time, xflags, and os fields are filled in with the gzip header |
contents. hcrc is set to true if there is a header CRC. (The header CRC |
contents. hcrc is set to true if there is a header CRC. (The header CRC |
was valid if done is set to one.) If extra is not Z_NULL, then extra_max | was valid if done is set to one.) If extra is not Z_NULL, then extra_max |
contains the maximum number of bytes to write to extra. Once done is true, |
contains the maximum number of bytes to write to extra. Once done is true, |
extra_len contains the actual extra field length, and extra contains the |
extra_len contains the actual extra field length, and extra contains the |
extra field, or that field truncated if extra_max is less than extra_len. |
extra field, or that field truncated if extra_max is less than extra_len. |
If name is not Z_NULL, then up to name_max characters are written there, |
If name is not Z_NULL, then up to name_max characters are written there, |
terminated with a zero unless the length is greater than name_max. If |
terminated with a zero unless the length is greater than name_max. If |
comment is not Z_NULL, then up to comm_max characters are written there, |
comment is not Z_NULL, then up to comm_max characters are written there, |
terminated with a zero unless the length is greater than comm_max. When | terminated with a zero unless the length is greater than comm_max. When any |
any of extra, name, or comment are not Z_NULL and the respective field is | of extra, name, or comment are not Z_NULL and the respective field is not |
not present in the header, then that field is set to Z_NULL to signal its | present in the header, then that field is set to Z_NULL to signal its |
absence. This allows the use of deflateSetHeader() with the returned |
absence. This allows the use of deflateSetHeader() with the returned |
structure to duplicate the header. However if those fields are set to |
structure to duplicate the header. However if those fields are set to |
allocated memory, then the application will need to save those pointers |
allocated memory, then the application will need to save those pointers |
elsewhere so that they can be eventually freed. |
elsewhere so that they can be eventually freed. |
|
|
If inflateGetHeader is not used, then the header information is simply | If inflateGetHeader is not used, then the header information is simply |
discarded. The header is always checked for validity, including the header |
discarded. The header is always checked for validity, including the header |
CRC if present. inflateReset() will reset the process to discard the header |
CRC if present. inflateReset() will reset the process to discard the header |
information. The application would need to call inflateGetHeader() again to |
information. The application would need to call inflateGetHeader() again to |
retrieve the header from the next gzip stream. |
retrieve the header from the next gzip stream. |
|
|
inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source | inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source |
stream state was inconsistent. |
stream state was inconsistent. |
*/ |
*/ |
|
|
Line 870 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm
|
Line 1018 ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm
|
See inflateBack() for the usage of these routines. |
See inflateBack() for the usage of these routines. |
|
|
inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of |
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 | the parameters are invalid, Z_MEM_ERROR if the internal state could not be |
be allocated, or Z_VERSION_ERROR if the version of the library does not | allocated, or Z_VERSION_ERROR if the version of the library does not match |
match the version of the header file. | 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)); |
typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); |
|
|
ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, |
ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, |
Line 883 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
Line 1032 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
out_func out, void FAR *out_desc)); |
out_func out, void FAR *out_desc)); |
/* |
/* |
inflateBack() does a raw inflate with a single call using a call-back |
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 | interface for input and output. This is potentially more efficient than |
file i/o applications in that it avoids copying between the output and the | inflate() for file i/o applications, in that it avoids copying between the |
sliding window by simply making the window itself the output buffer. This | output and the sliding window by simply making the window itself the output |
function trusts the application to not change the output buffer passed by | buffer. inflate() can be faster on modern CPUs when used with large |
the output function, at least until inflateBack() returns. | 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 |
inflateBackInit() must be called first to allocate the internal state |
and to initialize the state with the user-provided window buffer. |
and to initialize the state with the user-provided window buffer. |
inflateBack() may then be used multiple times to inflate a complete, raw |
inflateBack() may then be used multiple times to inflate a complete, raw |
deflate stream with each call. inflateBackEnd() is then called to free | deflate stream with each call. inflateBackEnd() is then called to free the |
the allocated state. | allocated state. |
|
|
A raw deflate stream is one with no zlib or gzip header or trailer. |
A raw deflate stream is one with no zlib or gzip header or trailer. |
This routine would normally be used in a utility that reads zip or gzip |
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 |
files and writes out uncompressed files. The utility would decode the |
header and process the trailer on its own, hence this routine expects | header and process the trailer on its own, hence this routine expects only |
only the raw deflate stream to decompress. This is different from the | the raw deflate stream to decompress. This is different from the normal |
normal behavior of inflate(), which expects either a zlib or gzip header and | behavior of inflate(), which expects either a zlib or gzip header and |
trailer around the deflate stream. |
trailer around the deflate stream. |
|
|
inflateBack() uses two subroutines supplied by the caller that are then |
inflateBack() uses two subroutines supplied by the caller that are then |
Line 926 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
Line 1076 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called |
calling inflateBack(). If strm->next_in is Z_NULL, then in() will be called |
immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in |
immediately for input. If strm->next_in is not Z_NULL, then strm->avail_in |
must also be initialized, and then if strm->avail_in is not zero, input will |
must also be initialized, and then if strm->avail_in is not zero, input will |
initially be taken from strm->next_in[0 .. strm->avail_in - 1]. | initially be taken from strm->next_in[0 .. strm->avail_in - 1]. |
|
|
The in_desc and out_desc parameters of inflateBack() is passed as the |
The in_desc and out_desc parameters of inflateBack() is passed as the |
first parameter of in() and out() respectively when they are called. These |
first parameter of in() and out() respectively when they are called. These |
Line 936 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
Line 1086 ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
|
On return, inflateBack() will set strm->next_in and strm->avail_in to |
On return, inflateBack() will set strm->next_in and strm->avail_in to |
pass back any unused input that was provided by the last in() call. The |
pass back any unused input that was provided by the last in() call. The |
return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR |
return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR |
if in() or out() returned an error, Z_DATA_ERROR if there was a format | if in() or out() returned an error, Z_DATA_ERROR if there was a format error |
error in the deflate stream (in which case strm->msg is set to indicate the | in the deflate stream (in which case strm->msg is set to indicate the nature |
nature of the error), or Z_STREAM_ERROR if the stream was not properly | of the error), or Z_STREAM_ERROR if the stream was not properly initialized. |
initialized. In the case of Z_BUF_ERROR, an input or output error can be | In the case of Z_BUF_ERROR, an input or output error can be distinguished |
distinguished using strm->next_in which will be Z_NULL only if in() returned | using strm->next_in which will be Z_NULL only if in() returned an error. If |
an error. If strm->next is not Z_NULL, then the Z_BUF_ERROR was due to | strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning |
out() returning non-zero. (in() will always be called before out(), so | non-zero. (in() will always be called before out(), so strm->next_in is |
strm->next_in is assured to be defined if out() returns non-zero.) Note | assured to be defined if out() returns non-zero.) Note that inflateBack() |
that inflateBack() cannot return Z_OK. | cannot return Z_OK. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); |
ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); |
Line 996 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
|
Line 1146 ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
|
27-31: 0 (reserved) |
27-31: 0 (reserved) |
*/ |
*/ |
|
|
|
#ifndef Z_SOLO |
|
|
/* utility functions */ |
/* utility functions */ |
|
|
/* |
/* |
The following utility functions are implemented on top of the | The following utility functions are implemented on top of the basic |
basic stream-oriented functions. To simplify the interface, some | stream-oriented functions. To simplify the interface, some default options |
default options are assumed (compression level and memory usage, | are assumed (compression level and memory usage, standard memory allocation |
standard memory allocation functions). The source code of these | functions). The source code of these utility functions can be modified if |
utility functions can easily be modified if you need special options. | you need special options. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, |
ZEXTERN int ZEXPORT compress OF((Bytef *dest, uLongf *destLen, |
const Bytef *source, uLong sourceLen)); |
const Bytef *source, uLong sourceLen)); |
/* |
/* |
Compresses the source buffer into the destination buffer. sourceLen is |
Compresses the source buffer into the destination buffer. sourceLen is |
the byte length of the source buffer. Upon entry, destLen is the total | the byte length of the source buffer. Upon entry, destLen is the total size |
size of the destination buffer, which must be at least the value returned | of the destination buffer, which must be at least the value returned by |
by compressBound(sourceLen). Upon exit, destLen is the actual size of the | compressBound(sourceLen). Upon exit, destLen is the actual size of the |
compressed buffer. |
compressed buffer. |
This function can be used to compress a whole file at once if the | |
input file is mmap'ed. | |
compress returns Z_OK if success, Z_MEM_ERROR if there was not |
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 |
enough memory, Z_BUF_ERROR if there was not enough room in the output |
buffer. |
buffer. |
Line 1026 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLong
|
Line 1176 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLong
|
const Bytef *source, uLong sourceLen, |
const Bytef *source, uLong sourceLen, |
int level)); |
int level)); |
/* |
/* |
Compresses the source buffer into the destination buffer. The level | Compresses the source buffer into the destination buffer. The level |
parameter has the same meaning as in deflateInit. sourceLen is the byte |
parameter has the same meaning as in deflateInit. sourceLen is the byte |
length of the source buffer. Upon entry, destLen is the total size of the | 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 |
destination buffer, which must be at least the value returned by |
compressBound(sourceLen). Upon exit, destLen is the actual size of the | compressBound(sourceLen). Upon exit, destLen is the actual size of the |
compressed buffer. |
compressed buffer. |
|
|
compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough |
Line 1041 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLong
|
Line 1191 ZEXTERN int ZEXPORT compress2 OF((Bytef *dest, uLong
|
ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); |
ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); |
/* |
/* |
compressBound() returns an upper bound on the compressed size after |
compressBound() returns an upper bound on the compressed size after |
compress() or compress2() on sourceLen bytes. It would be used before | compress() or compress2() on sourceLen bytes. It would be used before a |
a compress() or compress2() call to allocate the destination buffer. | compress() or compress2() call to allocate the destination buffer. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, |
ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen, |
const Bytef *source, uLong sourceLen)); |
const Bytef *source, uLong sourceLen)); |
/* |
/* |
Decompresses the source buffer into the destination buffer. sourceLen is |
Decompresses the source buffer into the destination buffer. sourceLen is |
the byte length of the source buffer. Upon entry, destLen is the total | the byte length of the source buffer. Upon entry, destLen is the total size |
size of the destination buffer, which must be large enough to hold the | of the destination buffer, which must be large enough to hold the entire |
entire uncompressed data. (The size of the uncompressed data must have | uncompressed data. (The size of the uncompressed data must have been saved |
been saved previously by the compressor and transmitted to the decompressor | previously by the compressor and transmitted to the decompressor by some |
by some mechanism outside the scope of this compression library.) | mechanism outside the scope of this compression library.) Upon exit, destLen |
Upon exit, destLen is the actual size of the compressed buffer. | is the actual size of the uncompressed buffer. |
This function can be used to decompress a whole file at once if the | |
input file is mmap'ed. | |
|
|
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not |
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 |
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. |
*/ |
*/ |
|
|
|
/* gzip file access functions */ |
|
|
typedef voidp gzFile; | /* |
| This library supports reading and writing files in gzip (.gz) format with |
| an interface similar to that of stdio, using the functions that start 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. |
| */ |
|
|
ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); | typedef struct gzFile_s *gzFile; /* semi-opaque gzip file descriptor */ |
| |
/* |
/* |
Opens a gzip (.gz) file for reading or writing. The mode parameter | ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); |
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", or 'R' for run-length encoding | |
as in "wb1R". (See the description of deflateInit2 for more information | |
about the strategy parameter.) | |
|
|
|
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.) '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 |
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 or if there was | gzopen returns NULL if the file could not be opened, if there was |
insufficient memory to allocate the (de)compression state; errno | insufficient memory to allocate the gzFile state, or if an invalid mode was |
can be checked to distinguish the two cases (if errno is zero, the | specified (an 'r', 'w', or 'a' was not provided, or '+' was provided). |
zlib error is Z_MEM_ERROR). */ | errno can be checked to determine if the reason gzopen failed was that the |
| file could not be opened. |
| */ |
|
|
ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); | ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); |
/* |
/* |
gzdopen() associates a gzFile with the file descriptor fd. File | gzdopen associates a gzFile with the file descriptor fd. File descriptors |
descriptors are obtained from calls like open, dup, creat, pipe or | are obtained from calls like open, dup, creat, pipe or fileno (if the file |
fileno (in the file has been previously opened with fopen). | has been previously opened with fopen). The mode parameter is as in gzopen. |
The mode parameter is as in gzopen. | |
The next call of gzclose on the returned gzFile will also close the | The next call of gzclose on the returned gzFile will also close the file |
file descriptor fd, just like fclose(fdopen(fd), mode) closes the file | descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor |
descriptor fd. If you want to keep fd open, use gzdopen(dup(fd), mode). | fd. If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd, |
gzdopen returns NULL if there was insufficient memory to allocate | mode);. The duplicated descriptor should be saved to avoid a leak, since |
the (de)compression state. | 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 |
| provided, or '+' was provided), or if fd is -1. The file descriptor is not |
| used until the next gz* read, write, seek, or close operation, so gzdopen |
| will not detect if fd is invalid (unless fd is -1). |
*/ |
*/ |
|
|
|
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). |
|
|
|
The new buffer size also affects the maximum length for gzprintf(). |
|
|
|
gzbuffer() returns 0 on success, or -1 on failure, such as being called |
|
too late. |
|
*/ |
|
|
ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); |
ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); |
/* |
/* |
Dynamically update the compression level or strategy. See the description | Dynamically update the compression level or strategy. See the description |
of deflateInit2 for the meaning of these parameters. |
of deflateInit2 for the meaning of these parameters. |
|
|
gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not |
gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not |
opened for writing. |
opened for writing. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); | ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); |
/* |
/* |
Reads the given number of uncompressed bytes from the compressed file. | Reads the given number of uncompressed bytes from the compressed file. If |
If the input file was not in gzip format, gzread copies the given number | the input file is not in gzip format, gzread copies the given number of |
of bytes into the buffer. | bytes into the buffer directly from the file. |
gzread returns the number of uncompressed bytes actually read (0 for | |
end of file, -1 for error). */ | |
|
|
ZEXTERN int ZEXPORT gzwrite OF((gzFile file, | After reaching the end of a gzip stream in the input, gzread will continue |
voidpc buf, unsigned 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. |
| */ |
| |
| ZEXTERN int ZEXPORT gzwrite OF((gzFile file, |
| voidpc buf, unsigned len)); |
/* |
/* |
Writes the given number of uncompressed bytes into the compressed file. |
Writes the given number of uncompressed bytes into the compressed file. |
gzwrite returns the number of uncompressed bytes actually written | gzwrite returns the number of uncompressed bytes written or 0 in case of |
(0 in case of error). | error. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); | ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...)); |
/* |
/* |
Converts, formats, and writes the args to the compressed file under | Converts, formats, and writes the arguments to the compressed file under |
control of the format string, as in fprintf. gzprintf returns the number of | control of the format string, as in fprintf. gzprintf returns the number of |
uncompressed bytes actually written (0 in case of error). The number of | uncompressed bytes actually written, or 0 in case of error. The number of |
uncompressed bytes written is limited to 4095. The caller should assure that | uncompressed bytes written is limited to 8191, or one less than the buffer |
this limit is not exceeded. If it is exceeded, then gzprintf() will return | size given to gzbuffer(). The caller should assure that this limit is not |
return an error (0) with nothing written. In this case, there may also be a | exceeded. If it is exceeded, then gzprintf() will return an error (0) with |
buffer overflow with unpredictable consequences, which is possible only if | nothing written. In this case, there may also be a buffer overflow with |
zlib was compiled with the insecure functions sprintf() or vsprintf() | unpredictable consequences, which is possible only if zlib was compiled with |
because the secure snprintf() or vsnprintf() functions were not available. | 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)); |
ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); |
/* |
/* |
Writes the given null-terminated string to the compressed file, excluding | Writes the given null-terminated string to the compressed file, excluding |
the terminating null character. |
the terminating null character. |
gzputs returns the number of characters written, or -1 in case of error. | |
| gzputs returns the number of characters written, or -1 in case of error. |
*/ |
*/ |
|
|
ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); |
ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); |
/* |
/* |
Reads bytes from the compressed file until len-1 characters are read, or | Reads bytes from the compressed file until len-1 characters are read, or a |
a newline character is read and transferred to buf, or an end-of-file | newline character is read and transferred to buf, or an end-of-file |
condition is encountered. The string is then terminated with a null | condition is encountered. If any characters are read or if len == 1, the |
character. | string is terminated with a null character. If no characters are read due |
gzgets returns buf, or Z_NULL in case of error. | to an end-of-file or len < 1, 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 |
| buf are indeterminate. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); | ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); |
/* |
/* |
Writes c, converted to an unsigned char, into the compressed file. | Writes c, converted to an unsigned char, into the compressed file. gzputc |
gzputc returns the value that was written, or -1 in case of error. | returns the value that was written, or -1 in case of error. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); | ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); |
/* |
/* |
Reads one byte from the compressed file. gzgetc returns this byte | Reads one byte from the compressed file. gzgetc returns this byte or -1 |
or -1 in case of end of file or error. | 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)); | ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); |
/* |
/* |
Push one character back onto the stream to be read again later. | Push one character back onto the stream to be read as the first character |
Only one character of push-back is allowed. gzungetc() returns the | on the next read. At least one character of push-back is allowed. |
character pushed, or -1 on failure. gzungetc() will fail if a | gzungetc() returns the character pushed, or -1 on failure. gzungetc() will |
character has been pushed but not read yet, or if c is -1. The pushed | fail if c is -1, and may fail if a character has been pushed but not read |
character will be discarded if the stream is repositioned with gzseek() | yet. If gzungetc is used immediately after gzopen or gzdopen, at least the |
or gzrewind(). | output buffer size of pushed characters is allowed. (See gzbuffer above.) |
| The pushed character will be discarded if the stream is repositioned with |
| gzseek() or gzrewind(). |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); | ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); |
/* |
/* |
Flushes all pending output into the compressed file. The parameter | Flushes all pending output into the compressed file. The parameter flush |
flush is as in the deflate() function. The return value is the zlib | is as in the deflate() function. The return value is the zlib error number |
error number (see function gzerror below). gzflush returns Z_OK if | (see function gzerror below). gzflush is only permitted when writing. |
the flush parameter is Z_FINISH and all output could be flushed. | |
gzflush should be called only when strictly necessary because it can | If the flush parameter is Z_FINISH, the remaining data is written and the |
degrade compression. | 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. |
| |
| gzflush should be called only when strictly necessary because it will |
| degrade compression if called too often. |
*/ |
*/ |
|
|
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 | ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, |
given compressed file. The offset represents a number of bytes in the | z_off_t offset, int whence)); |
uncompressed data stream. The whence parameter is defined as in lseek(2); | |
| Sets the starting position for the next gzread or gzwrite on the given |
| compressed 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. |
the value SEEK_END is not supported. |
|
|
If the file is opened for reading, this function is emulated but can be |
If the file is opened for reading, this function is emulated but can be |
extremely slow. If the file is opened for writing, only forward seeks are | extremely slow. If the file is opened for writing, only forward seeks are |
supported; gzseek then compresses a sequence of zeroes up to the new |
supported; gzseek then compresses a sequence of zeroes up to the new |
starting position. |
starting position. |
|
|
gzseek returns the resulting offset location as measured in bytes from | gzseek returns the resulting offset location as measured in bytes from |
the beginning of the uncompressed stream, or -1 in case of error, in |
the beginning of the uncompressed stream, or -1 in case of error, in |
particular if the file is opened for writing and the new starting position |
particular if the file is opened for writing and the new starting position |
would be before the current position. |
would be before the current position. |
Line 1203 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
|
Line 1449 ZEXTERN int ZEXPORT gzrewind OF((gzFile file));
|
/* |
/* |
Rewinds the given file. This function is supported only for reading. |
Rewinds the given 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)); |
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(). |
|
|
|
gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) |
|
*/ |
|
|
/* |
/* |
Returns the starting position for the next gzread or gzwrite on the | ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); |
given compressed file. This position represents a number of bytes in the | |
uncompressed data stream. | |
|
|
gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) | 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. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzeof OF((gzFile file)); |
ZEXTERN int ZEXPORT gzeof OF((gzFile file)); |
/* |
/* |
Returns 1 when EOF has previously been detected reading the given | Returns true (1) if the end-of-file indicator has been set while reading, |
input stream, otherwise zero. | 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 |
| has grown since the previous end of file was detected. |
*/ |
*/ |
|
|
ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); |
ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); |
/* |
/* |
Returns 1 if file is being read directly without decompression, otherwise | Returns true (1) if file is being copied directly while reading, or false |
zero. | (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. |
| |
| If gzdirect() is used immediately after gzopen() or gzdopen() it will |
| 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)); |
ZEXTERN int ZEXPORT gzclose OF((gzFile file)); |
/* |
/* |
Flushes all pending output if necessary, closes the compressed file | Flushes all pending output if necessary, closes the compressed file and |
and deallocates all the (de)compression state. The return value is the zlib | deallocates the (de)compression state. Note that once file is closed, you |
error number (see function gzerror below). | 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, 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)); |
|
ZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); |
|
/* |
|
Same as gzclose(), but gzclose_r() is only for use when reading, and |
|
gzclose_w() is only for use when writing or appending. The advantage to |
|
using these instead of gzclose() is that they avoid linking in zlib |
|
compression or decompression code that is not used when only reading or only |
|
writing respectively. If gzclose() is used, then both compression and |
|
decompression code will be included the application when linking to a static |
|
zlib library. |
|
*/ |
|
|
ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); |
ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); |
/* |
/* |
Returns the error message for the last error which occurred on the | Returns the error message for the last error which occurred on the given |
given compressed file. errnum is set to zlib error number. If an | compressed file. errnum is set to zlib error number. If an error occurred |
error occurred in the file system and not in the compression library, | in the file system and not in the compression library, errnum is set to |
errnum is set to Z_ERRNO and the application may consult errno | Z_ERRNO and the application may consult errno to get the exact error code. |
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 |
| closed, then the string previously returned by gzerror will no longer be |
| available. |
| |
| gzerror() should be used to distinguish errors from end-of-file for those |
| functions above that do not distinguish those cases in their return values. |
*/ |
*/ |
|
|
ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); |
ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); |
/* |
/* |
Clears the error and end-of-file flags for file. This is analogous to the | Clears 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 | clearerr() function in stdio. This is useful for continuing to read a gzip |
file that is being written concurrently. |
file that is being written concurrently. |
*/ |
*/ |
|
|
|
#endif /* !Z_SOLO */ |
|
|
/* checksum functions */ |
/* checksum functions */ |
|
|
/* |
/* |
These functions are not related to compression but are exported |
These functions are not related to compression but are exported |
anyway because they might be useful in applications using the | anyway because they might be useful in applications using the compression |
compression library. | library. |
*/ |
*/ |
|
|
ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); |
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 |
Update a running Adler-32 checksum with the bytes buf[0..len-1] and |
return the updated checksum. If buf is NULL, this function returns | return the updated checksum. If buf is Z_NULL, this function returns the |
the required initial value for the checksum. | required initial value for the checksum. |
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed | |
much faster. Usage example: | |
|
|
|
An Adler-32 checksum is almost as reliable as a CRC32 but can be computed |
|
much faster. |
|
|
|
Usage example: |
|
|
uLong adler = adler32(0L, Z_NULL, 0); |
uLong adler = adler32(0L, Z_NULL, 0); |
|
|
while (read_buffer(buffer, length) != EOF) { |
while (read_buffer(buffer, length) != EOF) { |
Line 1274 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const B
|
Line 1586 ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const B
|
if (adler != original_adler) error(); |
if (adler != original_adler) error(); |
*/ |
*/ |
|
|
|
/* |
ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, |
ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, |
z_off_t len2)); |
z_off_t len2)); |
/* | |
Combine two Adler-32 checksums into one. For two sequences of bytes, seq1 |
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 |
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 |
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 |
Update a running CRC-32 with the bytes buf[0..len-1] and return the |
updated CRC-32. If buf is NULL, this function returns the required initial | updated CRC-32. If buf is Z_NULL, this function returns the required |
value for the for the crc. Pre- and post-conditioning (one's complement) is | 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. |
performed within this function so it shouldn't be done by the application. |
|
|
Usage example: |
Usage example: |
|
|
uLong crc = crc32(0L, Z_NULL, 0); |
uLong crc = crc32(0L, Z_NULL, 0); |
Line 1299 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Byt
|
Line 1615 ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Byt
|
if (crc != original_crc) error(); |
if (crc != original_crc) error(); |
*/ |
*/ |
|
|
|
/* |
ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); |
ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); |
|
|
/* |
|
Combine two CRC-32 check values into one. For two sequences of bytes, |
Combine two CRC-32 check values into one. For two sequences of bytes, |
seq1 and seq2 with lengths len1 and len2, CRC-32 check values were |
seq1 and seq2 with lengths len1 and len2, CRC-32 check values were |
calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 |
calculated for each, crc1 and crc2. crc32_combine() returns the CRC-32 |
Line 1330 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp str
|
Line 1646 ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp str
|
const char *version, |
const char *version, |
int stream_size)); |
int stream_size)); |
#define deflateInit(strm, level) \ |
#define deflateInit(strm, level) \ |
deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream)) | deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream)) |
#define inflateInit(strm) \ |
#define inflateInit(strm) \ |
inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream)) | inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream)) |
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ |
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ |
deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ |
deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ |
(strategy), ZLIB_VERSION, sizeof(z_stream)) | (strategy), ZLIB_VERSION, (int)sizeof(z_stream)) |
#define inflateInit2(strm, windowBits) \ |
#define inflateInit2(strm, windowBits) \ |
inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) | inflateInit2_((strm), (windowBits), ZLIB_VERSION, \ |
| (int)sizeof(z_stream)) |
#define inflateBackInit(strm, windowBits, window) \ |
#define inflateBackInit(strm, windowBits, window) \ |
inflateBackInit_((strm), (windowBits), (window), \ |
inflateBackInit_((strm), (windowBits), (window), \ |
ZLIB_VERSION, sizeof(z_stream)) | ZLIB_VERSION, (int)sizeof(z_stream)) |
|
|
|
#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 |
|
* both are true, the application gets the *64 functions, and the regular |
|
* functions are changed to 64 bits) -- in case these are set on systems |
|
* without large file support, _LFS64_LARGEFILE must also be true |
|
*/ |
|
#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)); |
|
#endif |
|
|
|
#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 |
|
# else |
|
# define gzopen gzopen64 |
|
# define gzseek gzseek64 |
|
# define gztell gztell64 |
|
# define gzoffset gzoffset64 |
|
# define adler32_combine adler32_combine64 |
|
# define crc32_combine crc32_combine64 |
|
# 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)); |
|
# endif |
|
#else |
|
ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); |
|
ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int)); |
|
ZEXTERN z_off_t ZEXPORT gztell OF((gzFile)); |
|
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)); |
|
#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)); |
|
|
|
#endif /* !Z_SOLO */ |
|
|
|
/* hack for buggy compilers */ |
#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) |
#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) |
struct internal_state {int dummy;}; /* hack for buggy compilers */ | struct internal_state {int dummy;}; |
#endif |
#endif |
|
|
|
/* undocumented functions */ |
ZEXTERN const char * ZEXPORT zError OF((int)); |
ZEXTERN const char * ZEXPORT zError OF((int)); |
ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z)); | 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 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 |
#ifdef __cplusplus |
} |
} |