/* libmspack -- a library for working with Microsoft compression formats.
* (C) 2003-2019 Stuart Caie <kyzer@cabextract.org.uk>
*
* libmspack is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License (LGPL) version 2.1
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/** \mainpage
*
* \section intro Introduction
*
* libmspack is a library which provides compressors and decompressors,
* archivers and dearchivers for Microsoft compression formats.
*
* \section formats Formats supported
*
* The following file formats are supported:
* - SZDD files, which use LZSS compression
* - KWAJ files, which use LZSS, LZSS+Huffman or deflate compression
* - .HLP (MS Help) files, which use LZSS compression
* - .CAB (MS Cabinet) files, which use deflate, LZX or Quantum compression
* - .CHM (HTML Help) files, which use LZX compression
* - .LIT (MS EBook) files, which use LZX compression and DES encryption
* - .LZX (Exchange Offline Addressbook) files, which use LZX compression
*
* To determine the capabilities of the library, and the binary
* compatibility version of any particular compressor or decompressor, use
* the mspack_version() function. The UNIX library interface version is
* defined as the highest-versioned library component.
*
* \section starting Getting started
*
* The macro MSPACK_SYS_SELFTEST() should be used to ensure the library can
* be used. In particular, it checks if the caller is using 32-bit file I/O
* when the library is compiled for 64-bit file I/O and vice versa.
*
* If compiled normally, the library includes basic file I/O and memory
* management functionality using the standard C library. This can be
* customised and replaced entirely by creating a mspack_system structure.
*
* A compressor or decompressor for the required format must be
* instantiated before it can be used. Each construction function takes
* one parameter, which is either a pointer to a custom mspack_system
* structure, or NULL to use the default. The instantiation returned, if
* not NULL, contains function pointers (methods) to work with the given
* file format.
*
* For compression:
* - mspack_create_cab_compressor() creates a mscab_compressor
* - mspack_create_chm_compressor() creates a mschm_compressor
* - mspack_create_lit_compressor() creates a mslit_compressor
* - mspack_create_hlp_compressor() creates a mshlp_compressor
* - mspack_create_szdd_compressor() creates a msszdd_compressor
* - mspack_create_kwaj_compressor() creates a mskwaj_compressor
* - mspack_create_oab_compressor() creates a msoab_compressor
*
* For decompression:
* - mspack_create_cab_decompressor() creates a mscab_decompressor
* - mspack_create_chm_decompressor() creates a mschm_decompressor
* - mspack_create_lit_decompressor() creates a mslit_decompressor
* - mspack_create_hlp_decompressor() creates a mshlp_decompressor
* - mspack_create_szdd_decompressor() creates a msszdd_decompressor
* - mspack_create_kwaj_decompressor() creates a mskwaj_decompressor
* - mspack_create_oab_decompressor() creates a msoab_decompressor
*
* Once finished working with a format, each kind of
* compressor/decompressor has its own specific destructor:
* - mspack_destroy_cab_compressor()
* - mspack_destroy_cab_decompressor()
* - mspack_destroy_chm_compressor()
* - mspack_destroy_chm_decompressor()
* - mspack_destroy_lit_compressor()
* - mspack_destroy_lit_decompressor()
* - mspack_destroy_hlp_compressor()
* - mspack_destroy_hlp_decompressor()
* - mspack_destroy_szdd_compressor()
* - mspack_destroy_szdd_decompressor()
* - mspack_destroy_kwaj_compressor()
* - mspack_destroy_kwaj_decompressor()
* - mspack_destroy_oab_compressor()
* - mspack_destroy_oab_decompressor()
*
* Destroying a compressor or decompressor does not destroy any objects,
* structures or handles that have been created using that compressor or
* decompressor. Ensure that everything created or opened is destroyed or
* closed before compressor/decompressor is itself destroyed.
*
* \section errors Error codes
*
* All compressors and decompressors use the same set of error codes. Most
* methods return an error code directly. For methods which do not
* return error codes directly, the error code can be obtained with the
* last_error() method.
*
* - #MSPACK_ERR_OK is used to indicate success. This error code is defined
* as zero, all other code are non-zero.
* - #MSPACK_ERR_ARGS indicates that a method was called with inappropriate
* arguments.
* - #MSPACK_ERR_OPEN indicates that mspack_system::open() failed.
* - #MSPACK_ERR_READ indicates that mspack_system::read() failed.
* - #MSPACK_ERR_WRITE indicates that mspack_system::write() failed.
* - #MSPACK_ERR_SEEK indicates that mspack_system::seek() failed.
* - #MSPACK_ERR_NOMEMORY indicates that mspack_system::alloc() failed.
* - #MSPACK_ERR_SIGNATURE indicates that the file being read does not
* have the correct "signature". It is probably not a valid file for
* whatever format is being read.
* - #MSPACK_ERR_DATAFORMAT indicates that the file being used or read
* is corrupt.
* - #MSPACK_ERR_CHECKSUM indicates that a data checksum has failed.
* - #MSPACK_ERR_CRUNCH indicates an error occured during compression.
* - #MSPACK_ERR_DECRUNCH indicates an error occured during decompression.
*
* \section threading Multi-threading
*
* libmspack methods are reentrant and multithreading-safe when each
* thread has its own compressor or decompressor.
* You should not call multiple methods simultaneously on a single
* compressor or decompressor instance.
*
* If this may happen, you can either use one compressor or
* decompressor per thread, or you can use your preferred lock,
* semaphore or mutex library to ensure no more than one method on a
* compressor/decompressor is called simultaneously. libmspack will
* not do this locking for you.
*
* Example of incorrect behaviour:
* - thread 1 calls mspack_create_cab_decompressor()
* - thread 1 calls open()
* - thread 1 calls extract() for one file
* - thread 2 simultaneously calls extract() for another file
*
* Correct behaviour:
* - thread 1 calls mspack_create_cab_decompressor()
* - thread 2 calls mspack_create_cab_decompressor()
* - thread 1 calls its own open() / extract()
* - thread 2 simultaneously calls its own open() / extract()
*
* Also correct behaviour:
* - thread 1 calls mspack_create_cab_decompressor()
* - thread 1 locks a mutex for with the decompressor before
* calling any methods on it, and unlocks the mutex after each
* method returns.
* - thread 1 can share the results of open() with thread 2, and both
* can call extract(), provided they both guard against simultaneous
* use of extract(), and any other methods, with the mutex
*/
#ifndef LIB_MSPACK_H
#define LIB_MSPACK_H 1
#ifdef __cplusplus
extern "C" {
#endif
#include <sys/types.h>
#include <stdlib.h>
/**
* System self-test function, to ensure both library and calling program
* can use one another.
*
* A result of MSPACK_ERR_OK means the library and caller are
* compatible. Any other result indicates that the library and caller are
* not compatible and should not be used. In particular, a value of
* MSPACK_ERR_SEEK means the library and caller use different off_t
* datatypes.
*
* It should be used like so:
*
* @code
* int selftest_result;
* MSPACK_SYS_SELFTEST(selftest_result);
* if (selftest_result != MSPACK_ERR_OK) {
* fprintf(stderr, "incompatible with this build of libmspack\n");
* exit(0);
* }
* @endcode
*
* @param result an int variable to store the result of the self-test
*/
#define MSPACK_SYS_SELFTEST(result) do { \
(result) = mspack_sys_selftest_internal(sizeof(off_t)); \
} while (0)
/** Part of the MSPACK_SYS_SELFTEST() macro, must not be used directly. */
extern int mspack_sys_selftest_internal(int);
/**
* Enquire about the binary compatibility version of a specific interface in
* the library. Currently, the following interfaces are defined:
*
* - #MSPACK_VER_LIBRARY: the overall library
* - #MSPACK_VER_SYSTEM: the mspack_system interface
* - #MSPACK_VER_MSCABD: the mscab_decompressor interface
* - #MSPACK_VER_MSCABC: the mscab_compressor interface
* - #MSPACK_VER_MSCHMD: the mschm_decompressor interface
* - #MSPACK_VER_MSCHMC: the mschm_compressor interface
* - #MSPACK_VER_MSLITD: the mslit_decompressor interface
* - #MSPACK_VER_MSLITC: the mslit_compressor interface
* - #MSPACK_VER_MSHLPD: the mshlp_decompressor interface
* - #MSPACK_VER_MSHLPC: the mshlp_compressor interface
* - #MSPACK_VER_MSSZDDD: the msszdd_decompressor interface
* - #MSPACK_VER_MSSZDDC: the msszdd_compressor interface
* - #MSPACK_VER_MSKWAJD: the mskwaj_decompressor interface
* - #MSPACK_VER_MSKWAJC: the mskwaj_compressor interface
* - #MSPACK_VER_MSOABD: the msoab_decompressor interface
* - #MSPACK_VER_MSOABC: the msoab_compressor interface
*
* The result of the function should be interpreted as follows:
* - -1: this interface is completely unknown to the library
* - 0: this interface is known, but non-functioning
* - 1: this interface has all basic functionality
* - 2, 3, ...: this interface has additional functionality, clearly marked
* in the documentation as "version 2", "version 3" and so on.
*
* @param entity the interface to request current version of
* @return the version of the requested interface
*/
extern int mspack_version(int entity);
/** Pass to mspack_version() to get the overall library version */
#define MSPACK_VER_LIBRARY (0)
/** Pass to mspack_version() to get the mspack_system version */
#define MSPACK_VER_SYSTEM (1)
/** Pass to mspack_version() to get the mscab_decompressor version */
#define MSPACK_VER_MSCABD (2)
/** Pass to mspack_version() to get the mscab_compressor version */
#define MSPACK_VER_MSCABC (3)
/** Pass to mspack_version() to get the mschm_decompressor version */
#define MSPACK_VER_MSCHMD (4)
/** Pass to mspack_version() to get the mschm_compressor version */
#define MSPACK_VER_MSCHMC (5)
/** Pass to mspack_version() to get the mslit_decompressor version */
#define MSPACK_VER_MSLITD (6)
/** Pass to mspack_version() to get the mslit_compressor version */
#define MSPACK_VER_MSLITC (7)
/** Pass to mspack_version() to get the mshlp_decompressor version */
#define MSPACK_VER_MSHLPD (8)
/** Pass to mspack_version() to get the mshlp_compressor version */
#define MSPACK_VER_MSHLPC (9)
/** Pass to mspack_version() to get the msszdd_decompressor version */
#define MSPACK_VER_MSSZDDD (10)
/** Pass to mspack_version() to get the msszdd_compressor version */
#define MSPACK_VER_MSSZDDC (11)
/** Pass to mspack_version() to get the mskwaj_decompressor version */
#define MSPACK_VER_MSKWAJD (12)
/** Pass to mspack_version() to get the mskwaj_compressor version */
#define MSPACK_VER_MSKWAJC (13)
/** Pass to mspack_version() to get the msoab_decompressor version */
#define MSPACK_VER_MSOABD (14)
/** Pass to mspack_version() to get the msoab_compressor version */
#define MSPACK_VER_MSOABC (15)
/* --- file I/O abstraction ------------------------------------------------ */
/**
* A structure which abstracts file I/O and memory management.
*
* The library always uses the mspack_system structure for interaction
* with the file system and to allocate, free and copy all memory. It also
* uses it to send literal messages to the library user.
*
* When the library is compiled normally, passing NULL to a compressor or
* decompressor constructor will result in a default mspack_system being
* used, where all methods are implemented with the standard C library.
* However, all constructors support being given a custom created
* mspack_system structure, with the library user's own methods. This
* allows for more abstract interaction, such as reading and writing files
* directly to memory, or from a network socket or pipe.
*
* Implementors of an mspack_system structure should read all
* documentation entries for every structure member, and write methods
* which conform to those standards.
*/
struct mspack_system {
/**
* Opens a file for reading, writing, appending or updating.
*
* @param self a self-referential pointer to the mspack_system
* structure whose open() method is being called. If
* this pointer is required by close(), read(), write(),
* seek() or tell(), it should be stored in the result
* structure at this time.
* @param filename the file to be opened. It is passed directly from the
* library caller without being modified, so it is up to
* the caller what this parameter actually represents.
* @param mode one of #MSPACK_SYS_OPEN_READ (open an existing file
* for reading), #MSPACK_SYS_OPEN_WRITE (open a new file
* for writing), #MSPACK_SYS_OPEN_UPDATE (open an existing
* file for reading/writing from the start of the file) or
* #MSPACK_SYS_OPEN_APPEND (open an existing file for
* reading/writing from the end of the file)
* @return a pointer to a mspack_file structure. This structure officially
* contains no members, its true contents are up to the
* mspack_system implementor. It should contain whatever is needed
* for other mspack_system methods to operate. Returning the NULL
* pointer indicates an error condition.
* @see close(), read(), write(), seek(), tell(), message()
*/
struct mspack_file * (*open)(struct mspack_system *self,
const char *filename,
int mode);
/**
* Closes a previously opened file. If any memory was allocated for this
* particular file handle, it should be freed at this time.
*
* @param file the file to close
* @see open()
*/
void (*close)(struct mspack_file *file);
/**
* Reads a given number of bytes from an open file.
*
* @param file the file to read from
* @param buffer the location where the read bytes should be stored
* @param bytes the number of bytes to read from the file.
* @return the number of bytes successfully read (this can be less than
* the number requested), zero to mark the end of file, or less
* than zero to indicate an error. The library does not "retry"
* reads and assumes short reads are due to EOF, so you should
* avoid returning short reads because of transient errors.
* @see open(), write()
*/
int (*read)(struct mspack_file *file,
void *buffer,
int bytes);
/**
* Writes a given number of bytes to an open file.
*
* @param file the file to write to
* @param buffer the location where the written bytes should be read from
* @param bytes the number of bytes to write to the file.
* @return the number of bytes successfully written, this can be less
* than the number requested. Zero or less can indicate an error
* where no bytes at all could be written. All cases where less
* bytes were written than requested are considered by the library
* to be an error.
* @see open(), read()
*/
int (*write)(struct mspack_file *file,
void *buffer,
int bytes);
/**
* Seeks to a specific file offset within an open file.
*
* Sometimes the library needs to know the length of a file. It does
* this by seeking to the end of the file with seek(file, 0,
* MSPACK_SYS_SEEK_END), then calling tell(). Implementations may want
* to make a special case for this.
*
* Due to the potentially varying 32/64 bit datatype off_t on some
* architectures, the #MSPACK_SYS_SELFTEST macro MUST be used before
* using the library. If not, the error caused by the library passing an
* inappropriate stackframe to seek() is subtle and hard to trace.
*
* @param file the file to be seeked
* @param offset an offset to seek, measured in bytes
* @param mode one of #MSPACK_SYS_SEEK_START (the offset should be
* measured from the start of the file), #MSPACK_SYS_SEEK_CUR
* (the offset should be measured from the current file offset)
* or #MSPACK_SYS_SEEK_END (the offset should be measured from
* the end of the file)
* @return zero for success, non-zero for an error
* @see open(), tell()
*/
int (*seek)(struct mspack_file *file,
off_t offset,
int mode);
/**
* Returns the current file position (in bytes) of the given file.
*
* @param file the file whose file position is wanted
* @return the current file position of the file
* @see open(), seek()
*/
off_t (*tell)(struct mspack_file *file);
/**
* Used to send messages from the library to the user.
*
* Occasionally, the library generates warnings or other messages in
* plain english to inform the human user. These are informational only
* and can be ignored if not wanted.
*
* @param file may be a file handle returned from open() if this message
* pertains to a specific open file, or NULL if not related to
* a specific file.
* @param format a printf() style format string. It does NOT include a
* trailing newline.
* @see open()
*/
void (*message)(struct mspack_file *file,
const char *format,
...);
/**
* Allocates memory.
*
* @param self a self-referential pointer to the mspack_system
* structure whose alloc() method is being called.
* @param bytes the number of bytes to allocate
* @result a pointer to the requested number of bytes, or NULL if
* not enough memory is available
* @see free()
*/
void * (*alloc)(struct mspack_system *self,
size_t bytes);
/**
* Frees memory.
*
* @param ptr the memory to be freed. NULL is accepted and ignored.
* @see alloc()
*/
void (*free)(void *ptr);
/**
* Copies from one region of memory to another.
*
* The regions of memory are guaranteed not to overlap, are usually less
* than 256 bytes, and may not be aligned. Please note that the source
* parameter comes before the destination parameter, unlike the standard
* C function memcpy().
*
* @param src the region of memory to copy from
* @param dest the region of memory to copy to
* @param bytes the size of the memory region, in bytes
*/
void (*copy)(void *src,
void *dest,
size_t bytes);
/**
* A null pointer to mark the end of mspack_system. It must equal NULL.
*
* Should the mspack_system structure extend in the future, this NULL
* will be seen, rather than have an invalid method pointer called.
*/
void *null_ptr;
};
/** mspack_system::open() mode: open existing file for reading. */
#define MSPACK_SYS_OPEN_READ (0)
/** mspack_system::open() mode: open new file for writing */
#define MSPACK_SYS_OPEN_WRITE (1)
/** mspack_system::open() mode: open existing file for writing */
#define MSPACK_SYS_OPEN_UPDATE (2)
/** mspack_system::open() mode: open existing file for writing */
#define MSPACK_SYS_OPEN_APPEND (3)
/** mspack_system::seek() mode: seek relative to start of file */
#define MSPACK_SYS_SEEK_START (0)
/** mspack_system::seek() mode: seek relative to current offset */
#define MSPACK_SYS_SEEK_CUR (1)
/** mspack_system::seek() mode: seek relative to end of file */
#define MSPACK_SYS_SEEK_END (2)
/**
* A structure which represents an open file handle. The contents of this
* structure are determined by the implementation of the
* mspack_system::open() method.
*/
struct mspack_file {
int dummy;
};
/* --- error codes --------------------------------------------------------- */
/** Error code: no error */
#define MSPACK_ERR_OK (0)
/** Error code: bad arguments to method */
#define MSPACK_ERR_ARGS (1)
/** Error code: error opening file */
#define MSPACK_ERR_OPEN (2)
/** Error code: error reading file */
#define MSPACK_ERR_READ (3)
/** Error code: error writing file */
#define MSPACK_ERR_WRITE (4)
/** Error code: seek error */
#define MSPACK_ERR_SEEK (5)
/** Error code: out of memory */
#define MSPACK_ERR_NOMEMORY (6)
/** Error code: bad "magic id" in file */
#define MSPACK_ERR_SIGNATURE (7)
/** Error code: bad or corrupt file format */
#define MSPACK_ERR_DATAFORMAT (8)
/** Error code: bad checksum or CRC */
#define MSPACK_ERR_CHECKSUM (9)
/** Error code: error during compression */
#define MSPACK_ERR_CRUNCH (10)
/** Error code: error during decompression */
#define MSPACK_ERR_DECRUNCH (11)
/* --- functions available in library -------------------------------------- */
/** Creates a new CAB compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mscab_compressor or NULL
*/
extern struct mscab_compressor *
mspack_create_cab_compressor(struct mspack_system *sys);
/** Creates a new CAB decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mscab_decompressor or NULL
*/
extern struct mscab_decompressor *
mspack_create_cab_decompressor(struct mspack_system *sys);
/** Destroys an existing CAB compressor.
* @param self the #mscab_compressor to destroy
*/
extern void mspack_destroy_cab_compressor(struct mscab_compressor *self);
/** Destroys an existing CAB decompressor.
* @param self the #mscab_decompressor to destroy
*/
extern void mspack_destroy_cab_decompressor(struct mscab_decompressor *self);
/** Creates a new CHM compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mschm_compressor or NULL
*/
extern struct mschm_compressor *
mspack_create_chm_compressor(struct mspack_system *sys);
/** Creates a new CHM decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mschm_decompressor or NULL
*/
extern struct mschm_decompressor *
mspack_create_chm_decompressor(struct mspack_system *sys);
/** Destroys an existing CHM compressor.
* @param self the #mschm_compressor to destroy
*/
extern void mspack_destroy_chm_compressor(struct mschm_compressor *self);
/** Destroys an existing CHM decompressor.
* @param self the #mschm_decompressor to destroy
*/
extern void mspack_destroy_chm_decompressor(struct mschm_decompressor *self);
/** Creates a new LIT compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mslit_compressor or NULL
*/
extern struct mslit_compressor *
mspack_create_lit_compressor(struct mspack_system *sys);
/** Creates a new LIT decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mslit_decompressor or NULL
*/
extern struct mslit_decompressor *
mspack_create_lit_decompressor(struct mspack_system *sys);
/** Destroys an existing LIT compressor.
* @param self the #mslit_compressor to destroy
*/
extern void mspack_destroy_lit_compressor(struct mslit_compressor *self);
/** Destroys an existing LIT decompressor.
* @param self the #mslit_decompressor to destroy
*/
extern void mspack_destroy_lit_decompressor(struct mslit_decompressor *self);
/** Creates a new HLP compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mshlp_compressor or NULL
*/
extern struct mshlp_compressor *
mspack_create_hlp_compressor(struct mspack_system *sys);
/** Creates a new HLP decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mshlp_decompressor or NULL
*/
extern struct mshlp_decompressor *
mspack_create_hlp_decompressor(struct mspack_system *sys);
/** Destroys an existing hlp compressor.
* @param self the #mshlp_compressor to destroy
*/
extern void mspack_destroy_hlp_compressor(struct mshlp_compressor *self);
/** Destroys an existing hlp decompressor.
* @param self the #mshlp_decompressor to destroy
*/
extern void mspack_destroy_hlp_decompressor(struct mshlp_decompressor *self);
/** Creates a new SZDD compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #msszdd_compressor or NULL
*/
extern struct msszdd_compressor *
mspack_create_szdd_compressor(struct mspack_system *sys);
/** Creates a new SZDD decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #msszdd_decompressor or NULL
*/
extern struct msszdd_decompressor *
mspack_create_szdd_decompressor(struct mspack_system *sys);
/** Destroys an existing SZDD compressor.
* @param self the #msszdd_compressor to destroy
*/
extern void mspack_destroy_szdd_compressor(struct msszdd_compressor *self);
/** Destroys an existing SZDD decompressor.
* @param self the #msszdd_decompressor to destroy
*/
extern void mspack_destroy_szdd_decompressor(struct msszdd_decompressor *self);
/** Creates a new KWAJ compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mskwaj_compressor or NULL
*/
extern struct mskwaj_compressor *
mspack_create_kwaj_compressor(struct mspack_system *sys);
/** Creates a new KWAJ decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #mskwaj_decompressor or NULL
*/
extern struct mskwaj_decompressor *
mspack_create_kwaj_decompressor(struct mspack_system *sys);
/** Destroys an existing KWAJ compressor.
* @param self the #mskwaj_compressor to destroy
*/
extern void mspack_destroy_kwaj_compressor(struct mskwaj_compressor *self);
/** Destroys an existing KWAJ decompressor.
* @param self the #mskwaj_decompressor to destroy
*/
extern void mspack_destroy_kwaj_decompressor(struct mskwaj_decompressor *self);
/** Creates a new OAB compressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #msoab_compressor or NULL
*/
extern struct msoab_compressor *
mspack_create_oab_compressor(struct mspack_system *sys);
/** Creates a new OAB decompressor.
* @param sys a custom mspack_system structure, or NULL to use the default
* @return a #msoab_decompressor or NULL
*/
extern struct msoab_decompressor *
mspack_create_oab_decompressor(struct mspack_system *sys);
/** Destroys an existing OAB compressor.
* @param self the #msoab_compressor to destroy
*/
extern void mspack_destroy_oab_compressor(struct msoab_compressor *self);
/** Destroys an existing OAB decompressor.
* @param self the #msoab_decompressor to destroy
*/
extern void mspack_destroy_oab_decompressor(struct msoab_decompressor *self);
/* --- support for .CAB (MS Cabinet) file format --------------------------- */
/**
* A structure which represents a single cabinet file.
*
* All fields are READ ONLY.
*
* If this cabinet is part of a merged cabinet set, the #files and #folders
* fields are common to all cabinets in the set, and will be identical.
*
* @see mscab_decompressor::open(), mscab_decompressor::close(),
* mscab_decompressor::search()
*/
struct mscabd_cabinet {
/**
* The next cabinet in a chained list, if this cabinet was opened with
* mscab_decompressor::search(). May be NULL to mark the end of the
* list.
*/
struct mscabd_cabinet *next;
/**
* The filename of the cabinet. More correctly, the filename of the
* physical file that the cabinet resides in. This is given by the
* library user and may be in any format.
*/
const char *filename;
/** The file offset of cabinet within the physical file it resides in. */
off_t base_offset;
/** The length of the cabinet file in bytes. */
unsigned int length;
/** The previous cabinet in a cabinet set, or NULL. */
struct mscabd_cabinet *prevcab;
/** The next cabinet in a cabinet set, or NULL. */
struct mscabd_cabinet *nextcab;
/** The filename of the previous cabinet in a cabinet set, or NULL. */
char *prevname;
/** The filename of the next cabinet in a cabinet set, or NULL. */
char *nextname;
/** The name of the disk containing the previous cabinet in a cabinet
* set, or NULL.
*/
char *previnfo;
/** The name of the disk containing the next cabinet in a cabinet set,
* or NULL.
*/
char *nextinfo;
/** A list of all files in the cabinet or cabinet set. */
struct mscabd_file *files;
/** A list of all folders in the cabinet or cabinet set. */
struct mscabd_folder *folders;
/**
* The set ID of the cabinet. All cabinets in the same set should have
* the same set ID.
*/
unsigned short set_id;
/**
* The index number of the cabinet within the set. Numbering should
* start from 0 for the first cabinet in the set, and increment by 1 for
* each following cabinet.
*/
unsigned short set_index;
/**
* The number of bytes reserved in the header area of the cabinet.
*
* If this is non-zero and flags has MSCAB_HDR_RESV set, this data can
* be read by the calling application. It is of the given length,
* located at offset (base_offset + MSCAB_HDR_RESV_OFFSET) in the
* cabinet file.
*
* @see flags
*/
unsigned short header_resv;
/**
* Header flags.
*
* - MSCAB_HDR_PREVCAB indicates the cabinet is part of a cabinet set, and
* has a predecessor cabinet.
* - MSCAB_HDR_NEXTCAB indicates the cabinet is part of a cabinet set, and
* has a successor cabinet.
* - MSCAB_HDR_RESV indicates the cabinet has reserved header space.
*
* @see prevname, previnfo, nextname, nextinfo, header_resv
*/
int flags;
};
/** Offset from start of cabinet to the reserved header data (if present). */
#define MSCAB_HDR_RESV_OFFSET (0x28)
/** Cabinet header flag: cabinet has a predecessor */
#define MSCAB_HDR_PREVCAB (0x01)
/** Cabinet header flag: cabinet has a successor */
#define MSCAB_HDR_NEXTCAB (0x02)
/** Cabinet header flag: cabinet has reserved header space */
#define MSCAB_HDR_RESV (0x04)
/**
* A structure which represents a single folder in a cabinet or cabinet set.
*
* All fields are READ ONLY.
*
* A folder is a single compressed stream of data. When uncompressed, it
* holds the data of one or more files. A folder may be split across more
* than one cabinet.
*/
struct mscabd_folder {
/**
* A pointer to the next folder in this cabinet or cabinet set, or NULL
* if this is the final folder.
*/
struct mscabd_folder *next;
/**
* The compression format used by this folder.
*
* The macro MSCABD_COMP_METHOD() should be used on this field to get
* the algorithm used. The macro MSCABD_COMP_LEVEL() should be used to get
* the "compression level".
*
* @see MSCABD_COMP_METHOD(), MSCABD_COMP_LEVEL()
*/
int comp_type;
/**
* The total number of data blocks used by this folder. This includes
* data blocks present in other files, if this folder spans more than
* one cabinet.
*/
unsigned int num_blocks;
};
/**
* Returns the compression method used by a folder.
*
* @param comp_type a mscabd_folder::comp_type value
* @return one of #MSCAB_COMP_NONE, #MSCAB_COMP_MSZIP, #MSCAB_COMP_QUANTUM
* or #MSCAB_COMP_LZX
*/
#define MSCABD_COMP_METHOD(comp_type) ((comp_type) & 0x0F)
/**
* Returns the compression level used by a folder.
*
* @param comp_type a mscabd_folder::comp_type value
* @return the compression level. This is only defined by LZX and Quantum
* compression
*/
#define MSCABD_COMP_LEVEL(comp_type) (((comp_type) >> 8) & 0x1F)
/** Compression mode: no compression. */
#define MSCAB_COMP_NONE (0)
/** Compression mode: MSZIP (deflate) compression. */
#define MSCAB_COMP_MSZIP (1)
/** Compression mode: Quantum compression */
#define MSCAB_COMP_QUANTUM (2)
/** Compression mode: LZX compression */
#define MSCAB_COMP_LZX (3)
/**
* A structure which represents a single file in a cabinet or cabinet set.
*
* All fields are READ ONLY.
*/
struct mscabd_file {
/**
* The next file in the cabinet or cabinet set, or NULL if this is the
* final file.
*/
struct mscabd_file *next;
/**
* The filename of the file.
*
* A null terminated string of up to 255 bytes in length, it may be in
* either ISO-8859-1 or UTF8 format, depending on the file attributes.
*
* @see attribs
*/
char *filename;
/** The uncompressed length of the file, in bytes. */
unsigned int length;
/**
* File attributes.
*
* The following attributes are defined:
* - #MSCAB_ATTRIB_RDONLY indicates the file is write protected.
* - #MSCAB_ATTRIB_HIDDEN indicates the file is hidden.
* - #MSCAB_ATTRIB_SYSTEM indicates the file is a operating system file.
* - #MSCAB_ATTRIB_ARCH indicates the file is "archived".
* - #MSCAB_ATTRIB_EXEC indicates the file is an executable program.
* - #MSCAB_ATTRIB_UTF_NAME indicates the filename is in UTF8 format rather
* than ISO-8859-1.
*/
int attribs;
/** File's last modified time, hour field. */
char time_h;
/** File's last modified time, minute field. */
char time_m;
/** File's last modified time, second field. */
char time_s;
/** File's last modified date, day field. */
char date_d;
/** File's last modified date, month field. */
char date_m;
/** File's last modified date, year field. */
int date_y;
/** A pointer to the folder that contains this file. */
struct mscabd_folder *folder;
/** The uncompressed offset of this file in its folder. */
unsigned int offset;
};
/** mscabd_file::attribs attribute: file is read-only. */
#define MSCAB_ATTRIB_RDONLY (0x01)
/** mscabd_file::attribs attribute: file is hidden. */
#define MSCAB_ATTRIB_HIDDEN (0x02)
/** mscabd_file::attribs attribute: file is an operating system file. */
#define MSCAB_ATTRIB_SYSTEM (0x04)
/** mscabd_file::attribs attribute: file is "archived". */
#define MSCAB_ATTRIB_ARCH (0x20)
/** mscabd_file::attribs attribute: file is an executable program. */
#define MSCAB_ATTRIB_EXEC (0x40)
/** mscabd_file::attribs attribute: filename is UTF8, not ISO-8859-1. */
#define MSCAB_ATTRIB_UTF_NAME (0x80)
/** mscab_decompressor::set_param() parameter: search buffer size. */
#define MSCABD_PARAM_SEARCHBUF (0)
/** mscab_decompressor::set_param() parameter: repair MS-ZIP streams? */
#define MSCABD_PARAM_FIXMSZIP (1)
/** mscab_decompressor::set_param() parameter: size of decompression buffer */
#define MSCABD_PARAM_DECOMPBUF (2)
/** mscab_decompressor::set_param() parameter: salvage data from bad cabinets?
* If enabled, open() will skip file with bad folder indices or filenames
* rather than reject the whole cabinet, and extract() will limit rather than
* reject files with invalid offsets and lengths, and bad data block checksums
* will be ignored. Available only in CAB decoder version 2 and above.
*/
#define MSCABD_PARAM_SALVAGE (3)
/** TODO */
struct mscab_compressor {
int dummy;
};
/**
* A decompressor for .CAB (Microsoft Cabinet) files
*
* All fields are READ ONLY.
*
* @see mspack_create_cab_decompressor(), mspack_destroy_cab_decompressor()
*/
struct mscab_decompressor {
/**
* Opens a cabinet file and reads its contents.
*
* If the file opened is a valid cabinet file, all headers will be read
* and a mscabd_cabinet structure will be returned, with a full list of
* folders and files.
*
* In the case of an error occuring, NULL is returned and the error code
* is available from last_error().
*
* The filename pointer should be considered "in use" until close() is
* called on the cabinet.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param filename the filename of the cabinet file. This is passed
* directly to mspack_system::open().
* @return a pointer to a mscabd_cabinet structure, or NULL on failure
* @see close(), search(), last_error()
*/
struct mscabd_cabinet * (*open) (struct mscab_decompressor *self,
const char *filename);
/**
* Closes a previously opened cabinet or cabinet set.
*
* This closes a cabinet, all cabinets associated with it via the
* mscabd_cabinet::next, mscabd_cabinet::prevcab and
* mscabd_cabinet::nextcab pointers, and all folders and files. All
* memory used by these entities is freed.
*
* The cabinet pointer is now invalid and cannot be used again. All
* mscabd_folder and mscabd_file pointers from that cabinet or cabinet
* set are also now invalid, and cannot be used again.
*
* If the cabinet pointer given was created using search(), it MUST be
* the cabinet pointer returned by search() and not one of the later
* cabinet pointers further along the mscabd_cabinet::next chain.
* If extra cabinets have been added using append() or prepend(), these
* will all be freed, even if the cabinet pointer given is not the first
* cabinet in the set. Do NOT close() more than one cabinet in the set.
*
* The mscabd_cabinet::filename is not freed by the library, as it is
* not allocated by the library. The caller should free this itself if
* necessary, before it is lost forever.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param cab the cabinet to close
* @see open(), search(), append(), prepend()
*/
void (*close)(struct mscab_decompressor *self,
struct mscabd_cabinet *cab);
/**
* Searches a regular file for embedded cabinets.
*
* This opens a normal file with the given filename and will search the
* entire file for embedded cabinet files
*
* If any cabinets are found, the equivalent of open() is called on each
* potential cabinet file at the offset it was found. All successfully
* open()ed cabinets are kept in a list.
*
* The first cabinet found will be returned directly as the result of
* this method. Any further cabinets found will be chained in a list
* using the mscabd_cabinet::next field.
*
* In the case of an error occuring anywhere other than the simulated
* open(), NULL is returned and the error code is available from
* last_error().
*
* If no error occurs, but no cabinets can be found in the file, NULL is
* returned and last_error() returns MSPACK_ERR_OK.
*
* The filename pointer should be considered in use until close() is
* called on the cabinet.
*
* close() should only be called on the result of search(), not on any
* subsequent cabinets in the mscabd_cabinet::next chain.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param filename the filename of the file to search for cabinets. This
* is passed directly to mspack_system::open().
* @return a pointer to a mscabd_cabinet structure, or NULL
* @see close(), open(), last_error()
*/
struct mscabd_cabinet * (*search) (struct mscab_decompressor *self,
const char *filename);
/**
* Appends one mscabd_cabinet to another, forming or extending a cabinet
* set.
*
* This will attempt to append one cabinet to another such that
* <tt>(cab->nextcab == nextcab) && (nextcab->prevcab == cab)</tt> and
* any folders split between the two cabinets are merged.
*
* The cabinets MUST be part of a cabinet set -- a cabinet set is a
* cabinet that spans more than one physical cabinet file on disk -- and
* must be appropriately matched.
*
* It can be determined if a cabinet has further parts to load by
* examining the mscabd_cabinet::flags field:
*
* - if <tt>(flags & MSCAB_HDR_PREVCAB)</tt> is non-zero, there is a
* predecessor cabinet to open() and prepend(). Its MS-DOS
* case-insensitive filename is mscabd_cabinet::prevname
* - if <tt>(flags & MSCAB_HDR_NEXTCAB)</tt> is non-zero, there is a
* successor cabinet to open() and append(). Its MS-DOS case-insensitive
* filename is mscabd_cabinet::nextname
*
* If the cabinets do not match, an error code will be returned. Neither
* cabinet has been altered, and both should be closed seperately.
*
* Files and folders in a cabinet set are a single entity. All cabinets
* in a set use the same file list, which is updated as cabinets in the
* set are added. All pointers to mscabd_folder and mscabd_file
* structures in either cabinet must be discarded and re-obtained after
* merging.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param cab the cabinet which will be appended to,
* predecessor of nextcab
* @param nextcab the cabinet which will be appended,
* successor of cab
* @return an error code, or MSPACK_ERR_OK if successful
* @see prepend(), open(), close()
*/
int (*append) (struct mscab_decompressor *self,
struct mscabd_cabinet *cab,
struct mscabd_cabinet *nextcab);
/**
* Prepends one mscabd_cabinet to another, forming or extending a
* cabinet set.
*
* This will attempt to prepend one cabinet to another, such that
* <tt>(cab->prevcab == prevcab) && (prevcab->nextcab == cab)</tt>. In
* all other respects, it is identical to append(). See append() for the
* full documentation.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param cab the cabinet which will be prepended to,
* successor of prevcab
* @param prevcab the cabinet which will be prepended,
* predecessor of cab
* @return an error code, or MSPACK_ERR_OK if successful
* @see append(), open(), close()
*/
int (*prepend) (struct mscab_decompressor *self,
struct mscabd_cabinet *cab,
struct mscabd_cabinet *prevcab);
/**
* Extracts a file from a cabinet or cabinet set.
*
* This extracts a compressed file in a cabinet and writes it to the given
* filename.
*
* The MS-DOS filename of the file, mscabd_file::filename, is NOT USED
* by extract(). The caller must examine this MS-DOS filename, copy and
* change it as necessary, create directories as necessary, and provide
* the correct filename as a parameter, which will be passed unchanged
* to the decompressor's mspack_system::open()
*
* If the file belongs to a split folder in a multi-part cabinet set,
* and not enough parts of the cabinet set have been loaded and appended
* or prepended, an error will be returned immediately.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param file the file to be decompressed
* @param filename the filename of the file being written to
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*extract)(struct mscab_decompressor *self,
struct mscabd_file *file,
const char *filename);
/**
* Sets a CAB decompression engine parameter.
*
* The following parameters are defined:
* - #MSCABD_PARAM_SEARCHBUF: How many bytes should be allocated as a
* buffer when using search()? The minimum value is 4. The default
* value is 32768.
* - #MSCABD_PARAM_FIXMSZIP: If non-zero, extract() will ignore bad
* checksums and recover from decompression errors in MS-ZIP
* compressed folders. The default value is 0 (don't recover).
* - #MSCABD_PARAM_DECOMPBUF: How many bytes should be used as an input
* bit buffer by decompressors? The minimum value is 4. The default
* value is 4096.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @param param the parameter to set
* @param value the value to set the parameter to
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if there
* is a problem with either parameter or value.
* @see search(), extract()
*/
int (*set_param)(struct mscab_decompressor *self,
int param,
int value);
/**
* Returns the error code set by the most recently called method.
*
* This is useful for open() and search(), which do not return an error
* code directly.
*
* @param self a self-referential pointer to the mscab_decompressor
* instance being called
* @return the most recent error code
* @see open(), search()
*/
int (*last_error)(struct mscab_decompressor *self);
};
/* --- support for .CHM (HTMLHelp) file format ----------------------------- */
/**
* A structure which represents a file to be placed in a CHM helpfile.
*
* A contiguous array of these structures should be passed to
* mschm_compressor::generate(). The array list is terminated with an
* entry whose mschmc_file::section field is set to #MSCHMC_ENDLIST, the
* other fields in this entry are ignored.
*/
struct mschmc_file {
/** One of #MSCHMC_ENDLIST, #MSCHMC_UNCOMP or #MSCHMC_MSCOMP. */
int section;
/** The filename of the source file that will be added to the CHM. This
* is passed directly to mspack_system::open(). */
const char *filename;
/** The full path and filename of the file within the CHM helpfile, a
* UTF-1 encoded null-terminated string. */
char *chm_filename;
/** The length of the file, in bytes. This will be adhered to strictly
* and a read error will be issued if this many bytes cannot be read
* from the real file at CHM generation time. */
off_t length;
};
/**
* A structure which represents a section of a CHM helpfile.
*
* All fields are READ ONLY.
*
* Not used directly, but used as a generic base type for
* mschmd_sec_uncompressed and mschmd_sec_mscompressed.
*/
struct mschmd_section {
/** A pointer to the CHM helpfile that contains this section. */
struct mschmd_header *chm;
/**
* The section ID. Either 0 for the uncompressed section
* mschmd_sec_uncompressed, or 1 for the LZX compressed section
* mschmd_sec_mscompressed. No other section IDs are known.
*/
unsigned int id;
};
/**
* A structure which represents the uncompressed section of a CHM helpfile.
*
* All fields are READ ONLY.
*/
struct mschmd_sec_uncompressed {
/** Generic section data. */
struct mschmd_section base;
/** The file offset of where this section begins in the CHM helpfile. */
off_t offset;
};
/**
* A structure which represents the LZX compressed section of a CHM helpfile.
*
* All fields are READ ONLY.
*/
struct mschmd_sec_mscompressed {
/** Generic section data. */
struct mschmd_section base;
/** A pointer to the meta-file which represents all LZX compressed data. */
struct mschmd_file *content;
/** A pointer to the file which contains the LZX control data. */
struct mschmd_file *control;
/** A pointer to the file which contains the LZX reset table. */
struct mschmd_file *rtable;
/** A pointer to the file which contains the LZX span information.
* Available only in CHM decoder version 2 and above.
*/
struct mschmd_file *spaninfo;
};
/**
* A structure which represents a CHM helpfile.
*
* All fields are READ ONLY.
*/
struct mschmd_header {
/** The version of the CHM file format used in this file. */
unsigned int version;
/**
* The "timestamp" of the CHM helpfile.
*
* It is the lower 32 bits of a 64-bit value representing the number of
* centiseconds since 1601-01-01 00:00:00 UTC, plus 42. It is not useful
* as a timestamp, but it is useful as a semi-unique ID.
*/
unsigned int timestamp;
/**
* The default Language and Country ID (LCID) of the user who ran the
* HTMLHelp Compiler. This is not the language of the CHM file itself.
*/
unsigned int language;
/**
* The filename of the CHM helpfile. This is given by the library user
* and may be in any format.
*/
const char *filename;
/** The length of the CHM helpfile, in bytes. */
off_t length;
/** A list of all non-system files in the CHM helpfile. */
struct mschmd_file *files;
/**
* A list of all system files in the CHM helpfile.
*
* System files are files which begin with "::". They are meta-files
* generated by the CHM creation process.
*/
struct mschmd_file *sysfiles;
/** The section 0 (uncompressed) data in this CHM helpfile. */
struct mschmd_sec_uncompressed sec0;
/** The section 1 (MSCompressed) data in this CHM helpfile. */
struct mschmd_sec_mscompressed sec1;
/** The file offset of the first PMGL/PMGI directory chunk. */
off_t dir_offset;
/** The number of PMGL/PMGI directory chunks in this CHM helpfile. */
unsigned int num_chunks;
/** The size of each PMGL/PMGI chunk, in bytes. */
unsigned int chunk_size;
/** The "density" of the quick-reference section in PMGL/PMGI chunks. */
unsigned int density;
/** The depth of the index tree.
*
* - if 1, there are no PMGI chunks, only PMGL chunks.
* - if 2, there is 1 PMGI chunk. All chunk indices point to PMGL chunks.
* - if 3, the root PMGI chunk points to secondary PMGI chunks, which in
* turn point to PMGL chunks.
* - and so on...
*/
unsigned int depth;
/**
* The number of the root PMGI chunk.
*
* If there is no index in the CHM helpfile, this will be 0xFFFFFFFF.
*/
unsigned int index_root;
/**
* The number of the first PMGL chunk. Usually zero.
* Available only in CHM decoder version 2 and above.
*/
unsigned int first_pmgl;
/**
* The number of the last PMGL chunk. Usually num_chunks-1.
* Available only in CHM decoder version 2 and above.
*/
unsigned int last_pmgl;
/**
* A cache of loaded chunks, filled in by mschm_decoder::fast_find().
* Available only in CHM decoder version 2 and above.
*/
unsigned char **chunk_cache;
};
/**
* A structure which represents a file stored in a CHM helpfile.
*
* All fields are READ ONLY.
*/
struct mschmd_file {
/**
* A pointer to the next file in the list, or NULL if this is the final
* file.
*/
struct mschmd_file *next;
/**
* A pointer to the section that this file is located in. Indirectly,
* it also points to the CHM helpfile the file is located in.
*/
struct mschmd_section *section;
/** The offset within the section data that this file is located at. */
off_t offset;
/** The length of this file, in bytes */
off_t length;
/** The filename of this file -- a null terminated string in UTF-8. */
char *filename;
};
/** mschmc_file::section value: end of CHM file list */
#define MSCHMC_ENDLIST (0)
/** mschmc_file::section value: this file is in the Uncompressed section */
#define MSCHMC_UNCOMP (1)
/** mschmc_file::section value: this file is in the MSCompressed section */
#define MSCHMC_MSCOMP (2)
/** mschm_compressor::set_param() parameter: "timestamp" header */
#define MSCHMC_PARAM_TIMESTAMP (0)
/** mschm_compressor::set_param() parameter: "language" header */
#define MSCHMC_PARAM_LANGUAGE (1)
/** mschm_compressor::set_param() parameter: LZX window size */
#define MSCHMC_PARAM_LZXWINDOW (2)
/** mschm_compressor::set_param() parameter: intra-chunk quickref density */
#define MSCHMC_PARAM_DENSITY (3)
/** mschm_compressor::set_param() parameter: whether to create indices */
#define MSCHMC_PARAM_INDEX (4)
/**
* A compressor for .CHM (Microsoft HTMLHelp) files.
*
* All fields are READ ONLY.
*
* @see mspack_create_chm_compressor(), mspack_destroy_chm_compressor()
*/
struct mschm_compressor {
/**
* Generates a CHM help file.
*
* The help file will contain up to two sections, an Uncompressed
* section and potentially an MSCompressed (LZX compressed)
* section.
*
* While the contents listing of a CHM file is always in lexical order,
* the file list passed in will be taken as the correct order for files
* within the sections. It is in your interest to place similar files
* together for better compression.
*
* There are two modes of generation, to use a temporary file or not to
* use one. See use_temporary_file() for the behaviour of generate() in
* these two different modes.
*
* @param self a self-referential pointer to the mschm_compressor
* instance being called
* @param file_list an array of mschmc_file structures, terminated
* with an entry whose mschmc_file::section field is
* #MSCHMC_ENDLIST. The order of the list is
* preserved within each section. The length of any
* mschmc_file::chm_filename string cannot exceed
* roughly 4096 bytes. Each source file must be able
* to supply as many bytes as given in the
* mschmc_file::length field.
* @param output_file the file to write the generated CHM helpfile to.
* This is passed directly to mspack_system::open()
* @return an error code, or MSPACK_ERR_OK if successful
* @see use_temporary_file() set_param()
*/
int (*generate)(struct mschm_compressor *self,
struct mschmc_file file_list[],
const char *output_file);
/**
* Specifies whether a temporary file is used during CHM generation.
*
* The CHM file format includes data about the compressed section (such
* as its overall size) that is stored in the output CHM file prior to
* the compressed section itself. This unavoidably requires that the
* compressed section has to be generated, before these details can be
* set. There are several ways this can be handled. Firstly, the
* compressed section could be generated entirely in memory before
* writing any of the output CHM file. This approach is not used in
* libmspack, as the compressed section can exceed the addressable
* memory space on most architectures.
*
* libmspack has two options, either to write these unknowable sections
* with blank data, generate the compressed section, then re-open the
* output file for update once the compressed section has been
* completed, or to write the compressed section to a temporary file,
* then write the entire output file at once, performing a simple
* file-to-file copy for the compressed section.
*
* The simple solution of buffering the entire compressed section in
* memory can still be used, if desired. As the temporary file's
* filename is passed directly to mspack_system::open(), it is possible
* for a custom mspack_system implementation to hold this file in memory,
* without writing to a disk.
*
* If a temporary file is set, generate() performs the following
* sequence of events: the temporary file is opened for writing, the
* compression algorithm writes to the temporary file, the temporary
* file is closed. Then the output file is opened for writing and the
* temporary file is re-opened for reading. The output file is written
* and the temporary file is read from. Both files are then closed. The
* temporary file itself is not deleted. If that is desired, the
* temporary file should be deleted after the completion of generate(),
* if it exists.
*
* If a temporary file is set not to be used, generate() performs the
* following sequence of events: the output file is opened for writing,
* then it is written and closed. The output file is then re-opened for
* update, the appropriate sections are seek()ed to and re-written, then
* the output file is closed.
*
* @param self a self-referential pointer to the
* mschm_compressor instance being called
* @param use_temp_file non-zero if the temporary file should be used,
* zero if the temporary file should not be used.
* @param temp_file a file to temporarily write compressed data to,
* before opening it for reading and copying the
* contents to the output file. This is passed
* directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
* @see generate()
*/
int (*use_temporary_file)(struct mschm_compressor *self,
int use_temp_file,
const char *temp_file);
/**
* Sets a CHM compression engine parameter.
*
* The following parameters are defined:
* - #MSCHMC_PARAM_TIMESTAMP: Sets the "timestamp" of the CHM file
* generated. This is not a timestamp, see mschmd_header::timestamp
* for a description. If this timestamp is 0, generate() will use its
* own algorithm for making a unique ID, based on the lengths and
* names of files in the CHM itself. Defaults to 0, any value between
* 0 and (2^32)-1 is valid.
* - #MSCHMC_PARAM_LANGUAGE: Sets the "language" of the CHM file
* generated. This is not the language used in the CHM file, but the
* language setting of the user who ran the HTMLHelp compiler. It
* defaults to 0x0409. The valid range is between 0x0000 and 0x7F7F.
* - #MSCHMC_PARAM_LZXWINDOW: Sets the size of the LZX history window,
* which is also the interval at which the compressed data stream can be
* randomly accessed. The value is not a size in bytes, but a power of
* two. The default value is 16 (which makes the window 2^16 bytes, or
* 64 kilobytes), the valid range is from 15 (32 kilobytes) to 21 (2
* megabytes).
* - #MSCHMC_PARAM_DENSITY: Sets the "density" of quick reference
* entries stored at the end of directory listing chunk. Each chunk is
* 4096 bytes in size, and contains as many file entries as there is
* room for. At the other end of the chunk, a list of "quick reference"
* pointers is included. The offset of every 'N'th file entry is given a
* quick reference, where N = (2^density) + 1. The default density is
* 2. The smallest density is 0 (N=2), the maximum is 10 (N=1025). As
* each file entry requires at least 5 bytes, the maximum number of
* entries in a single chunk is roughly 800, so the maximum value 10
* can be used to indicate there are no quickrefs at all.
* - #MSCHMC_PARAM_INDEX: Sets whether or not to include quick lookup
* index chunk(s), in addition to normal directory listing chunks. A
* value of zero means no index chunks will be created, a non-zero value
* means index chunks will be created. The default is zero, "don't
* create an index".
*
* @param self a self-referential pointer to the mschm_compressor
* instance being called
* @param param the parameter to set
* @param value the value to set the parameter to
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if there
* is a problem with either parameter or value.
* @see generate()
*/
int (*set_param)(struct mschm_compressor *self,
int param,
int value);
/**
* Returns the error code set by the most recently called method.
*
* @param self a self-referential pointer to the mschm_compressor
* instance being called
* @return the most recent error code
* @see set_param(), generate()
*/
int (*last_error)(struct mschm_compressor *self);
};
/**
* A decompressor for .CHM (Microsoft HTMLHelp) files
*
* All fields are READ ONLY.
*
* @see mspack_create_chm_decompressor(), mspack_destroy_chm_decompressor()
*/
struct mschm_decompressor {
/**
* Opens a CHM helpfile and reads its contents.
*
* If the file opened is a valid CHM helpfile, all headers will be read
* and a mschmd_header structure will be returned, with a full list of
* files.
*
* In the case of an error occuring, NULL is returned and the error code
* is available from last_error().
*
* The filename pointer should be considered "in use" until close() is
* called on the CHM helpfile.
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @param filename the filename of the CHM helpfile. This is passed
* directly to mspack_system::open().
* @return a pointer to a mschmd_header structure, or NULL on failure
* @see close()
*/
struct mschmd_header *(*open)(struct mschm_decompressor *self,
const char *filename);
/**
* Closes a previously opened CHM helpfile.
*
* This closes a CHM helpfile, frees the mschmd_header and all
* mschmd_file structures associated with it (if any). This works on
* both helpfiles opened with open() and helpfiles opened with
* fast_open().
*
* The CHM header pointer is now invalid and cannot be used again. All
* mschmd_file pointers referencing that CHM are also now invalid, and
* cannot be used again.
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @param chm the CHM helpfile to close
* @see open(), fast_open()
*/
void (*close)(struct mschm_decompressor *self,
struct mschmd_header *chm);
/**
* Extracts a file from a CHM helpfile.
*
* This extracts a file from a CHM helpfile and writes it to the given
* filename. The filename of the file, mscabd_file::filename, is not
* used by extract(), but can be used by the caller as a guide for
* constructing an appropriate filename.
*
* This method works both with files found in the mschmd_header::files
* and mschmd_header::sysfiles list and mschmd_file structures generated
* on the fly by fast_find().
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @param file the file to be decompressed
* @param filename the filename of the file being written to
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*extract)(struct mschm_decompressor *self,
struct mschmd_file *file,
const char *filename);
/**
* Returns the error code set by the most recently called method.
*
* This is useful for open() and fast_open(), which do not return an
* error code directly.
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @return the most recent error code
* @see open(), extract()
*/
int (*last_error)(struct mschm_decompressor *self);
/**
* Opens a CHM helpfile quickly.
*
* If the file opened is a valid CHM helpfile, only essential headers
* will be read. A mschmd_header structure will be still be returned, as
* with open(), but the mschmd_header::files field will be NULL. No
* files details will be automatically read. The fast_find() method
* must be used to obtain file details.
*
* In the case of an error occuring, NULL is returned and the error code
* is available from last_error().
*
* The filename pointer should be considered "in use" until close() is
* called on the CHM helpfile.
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @param filename the filename of the CHM helpfile. This is passed
* directly to mspack_system::open().
* @return a pointer to a mschmd_header structure, or NULL on failure
* @see open(), close(), fast_find(), extract()
*/
struct mschmd_header *(*fast_open)(struct mschm_decompressor *self,
const char *filename);
/**
* Finds file details quickly.
*
* Instead of reading all CHM helpfile headers and building a list of
* files, fast_open() and fast_find() are intended for finding file
* details only when they are needed. The CHM file format includes an
* on-disk file index to allow this.
*
* Given a case-sensitive filename, fast_find() will search the on-disk
* index for that file.
*
* If the file was found, the caller-provided mschmd_file structure will
* be filled out like so:
* - section: the correct value for the found file
* - offset: the correct value for the found file
* - length: the correct value for the found file
* - all other structure elements: NULL or 0
*
* If the file was not found, MSPACK_ERR_OK will still be returned as the
* result, but the caller-provided structure will be filled out like so:
* - section: NULL
* - offset: 0
* - length: 0
* - all other structure elements: NULL or 0
*
* This method is intended to be used in conjunction with CHM helpfiles
* opened with fast_open(), but it also works with helpfiles opened
* using the regular open().
*
* @param self a self-referential pointer to the mschm_decompressor
* instance being called
* @param chm the CHM helpfile to search for the file
* @param filename the filename of the file to search for
* @param f_ptr a pointer to a caller-provded mschmd_file structure
* @param f_size <tt>sizeof(struct mschmd_file)</tt>
* @return an error code, or MSPACK_ERR_OK if successful
* @see open(), close(), fast_find(), extract()
*/
int (*fast_find)(struct mschm_decompressor *self,
struct mschmd_header *chm,
const char *filename,
struct mschmd_file *f_ptr,
int f_size);
};
/* --- support for .LIT (EBook) file format -------------------------------- */
/** TODO */
struct mslit_compressor {
int dummy;
};
/** TODO */
struct mslit_decompressor {
int dummy;
};
/* --- support for .HLP (MS Help) file format ------------------------------ */
/** TODO */
struct mshlp_compressor {
int dummy;
};
/** TODO */
struct mshlp_decompressor {
int dummy;
};
/* --- support for SZDD file format ---------------------------------------- */
/** msszdd_compressor::set_param() parameter: the missing character */
#define MSSZDDC_PARAM_MISSINGCHAR (0)
/** msszddd_header::format value - a regular SZDD file */
#define MSSZDD_FMT_NORMAL (0)
/** msszddd_header::format value - a special QBasic SZDD file */
#define MSSZDD_FMT_QBASIC (1)
/**
* A structure which represents an SZDD compressed file.
*
* All fields are READ ONLY.
*/
struct msszddd_header {
/** The file format; either #MSSZDD_FMT_NORMAL or #MSSZDD_FMT_QBASIC */
int format;
/** The amount of data in the SZDD file once uncompressed. */
off_t length;
/**
* The last character in the filename, traditionally replaced with an
* underscore to show the file is compressed. The null character is used
* to show that this character has not been stored (e.g. because the
* filename is not known). Generally, only characters that may appear in
* an MS-DOS filename (except ".") are valid.
*/
char missing_char;
};
/**
* A compressor for the SZDD file format.
*
* All fields are READ ONLY.
*
* @see mspack_create_szdd_compressor(), mspack_destroy_szdd_compressor()
*/
struct msszdd_compressor {
/**
* Reads an input file and creates a compressed output file in the
* SZDD compressed file format. The SZDD compression format is quick
* but gives poor compression. It is possible for the compressed output
* file to be larger than the input file.
*
* Conventionally, SZDD compressed files have the final character in
* their filename replaced with an underscore, to show they are
* compressed. The missing character is stored in the compressed file
* itself. This is due to the restricted filename conventions of MS-DOS,
* most operating systems, such as UNIX, simply append another file
* extension to the existing filename. As mspack does not deal with
* filenames, this is left up to you. If you wish to set the missing
* character stored in the file header, use set_param() with the
* #MSSZDDC_PARAM_MISSINGCHAR parameter.
*
* "Stream" compression (where the length of the input data is not
* known) is not possible. The length of the input data is stored in the
* header of the SZDD file and must therefore be known before any data
* is compressed. Due to technical limitations of the file format, the
* maximum size of uncompressed file that will be accepted is 2147483647
* bytes.
*
* @param self a self-referential pointer to the msszdd_compressor
* instance being called
* @param input the name of the file to compressed. This is passed
* passed directly to mspack_system::open()
* @param output the name of the file to write compressed data to.
* This is passed directly to mspack_system::open().
* @param length the length of the uncompressed file, or -1 to indicate
* that this should be determined automatically by using
* mspack_system::seek() on the input file.
* @return an error code, or MSPACK_ERR_OK if successful
* @see set_param()
*/
int (*compress)(struct msszdd_compressor *self,
const char *input,
const char *output,
off_t length);
/**
* Sets an SZDD compression engine parameter.
*
* The following parameters are defined:
* - #MSSZDDC_PARAM_CHARACTER: the "missing character", the last character
* in the uncompressed file's filename, which is traditionally replaced
* with an underscore to show the file is compressed. Traditionally,
* this can only be a character that is a valid part of an MS-DOS,
* filename, but libmspack permits any character between 0x00 and 0xFF
* to be stored. 0x00 is the default, and it represents "no character
* stored".
*
* @param self a self-referential pointer to the msszdd_compressor
* instance being called
* @param param the parameter to set
* @param value the value to set the parameter to
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if there
* is a problem with either parameter or value.
* @see compress()
*/
int (*set_param)(struct msszdd_compressor *self,
int param,
int value);
/**
* Returns the error code set by the most recently called method.
*
* @param self a self-referential pointer to the msszdd_compressor
* instance being called
* @return the most recent error code
* @see compress()
*/
int (*last_error)(struct mschm_decompressor *self);
};
/**
* A decompressor for SZDD compressed files.
*
* All fields are READ ONLY.
*
* @see mspack_create_szdd_decompressor(), mspack_destroy_szdd_decompressor()
*/
struct msszdd_decompressor {
/**
* Opens a SZDD file and reads the header.
*
* If the file opened is a valid SZDD file, all headers will be read and
* a msszddd_header structure will be returned.
*
* In the case of an error occuring, NULL is returned and the error code
* is available from last_error().
*
* The filename pointer should be considered "in use" until close() is
* called on the SZDD file.
*
* @param self a self-referential pointer to the msszdd_decompressor
* instance being called
* @param filename the filename of the SZDD compressed file. This is
* passed directly to mspack_system::open().
* @return a pointer to a msszddd_header structure, or NULL on failure
* @see close()
*/
struct msszddd_header *(*open)(struct msszdd_decompressor *self,
const char *filename);
/**
* Closes a previously opened SZDD file.
*
* This closes a SZDD file and frees the msszddd_header associated with
* it.
*
* The SZDD header pointer is now invalid and cannot be used again.
*
* @param self a self-referential pointer to the msszdd_decompressor
* instance being called
* @param szdd the SZDD file to close
* @see open()
*/
void (*close)(struct msszdd_decompressor *self,
struct msszddd_header *szdd);
/**
* Extracts the compressed data from a SZDD file.
*
* This decompresses the compressed SZDD data stream and writes it to
* an output file.
*
* @param self a self-referential pointer to the msszdd_decompressor
* instance being called
* @param szdd the SZDD file to extract data from
* @param filename the filename to write the decompressed data to. This
* is passed directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*extract)(struct msszdd_decompressor *self,
struct msszddd_header *szdd,
const char *filename);
/**
* Decompresses an SZDD file to an output file in one step.
*
* This opens an SZDD file as input, reads the header, then decompresses
* the compressed data immediately to an output file, finally closing
* both the input and output file. It is more convenient to use than
* open() then extract() then close(), if you do not need to know the
* SZDD output size or missing character.
*
* @param self a self-referential pointer to the msszdd_decompressor
* instance being called
* @param input the filename of the input SZDD file. This is passed
* directly to mspack_system::open().
* @param output the filename to write the decompressed data to. This
* is passed directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*decompress)(struct msszdd_decompressor *self,
const char *input,
const char *output);
/**
* Returns the error code set by the most recently called method.
*
* This is useful for open() which does not return an
* error code directly.
*
* @param self a self-referential pointer to the msszdd_decompressor
* instance being called
* @return the most recent error code
* @see open(), extract(), decompress()
*/
int (*last_error)(struct msszdd_decompressor *self);
};
/* --- support for KWAJ file format ---------------------------------------- */
/** mskwaj_compressor::set_param() parameter: compression type */
#define MSKWAJC_PARAM_COMP_TYPE (0)
/** mskwaj_compressor::set_param() parameter: include the length of the
* uncompressed file in the header?
*/
#define MSKWAJC_PARAM_INCLUDE_LENGTH (1)
/** KWAJ compression type: no compression. */
#define MSKWAJ_COMP_NONE (0)
/** KWAJ compression type: no compression, 0xFF XOR "encryption". */
#define MSKWAJ_COMP_XOR (1)
/** KWAJ compression type: LZSS (same method as SZDD) */
#define MSKWAJ_COMP_SZDD (2)
/** KWAJ compression type: LZ+Huffman compression */
#define MSKWAJ_COMP_LZH (3)
/** KWAJ compression type: MSZIP */
#define MSKWAJ_COMP_MSZIP (4)
/** KWAJ optional header flag: decompressed file length is included */
#define MSKWAJ_HDR_HASLENGTH (0x01)
/** KWAJ optional header flag: unknown 2-byte structure is included */
#define MSKWAJ_HDR_HASUNKNOWN1 (0x02)
/** KWAJ optional header flag: unknown multi-sized structure is included */
#define MSKWAJ_HDR_HASUNKNOWN2 (0x04)
/** KWAJ optional header flag: file name (no extension) is included */
#define MSKWAJ_HDR_HASFILENAME (0x08)
/** KWAJ optional header flag: file extension is included */
#define MSKWAJ_HDR_HASFILEEXT (0x10)
/** KWAJ optional header flag: extra text is included */
#define MSKWAJ_HDR_HASEXTRATEXT (0x20)
/**
* A structure which represents an KWAJ compressed file.
*
* All fields are READ ONLY.
*/
struct mskwajd_header {
/** The compression type; should be one of #MSKWAJ_COMP_NONE,
* #MSKWAJ_COMP_XOR, #MSKWAJ_COMP_SZDD or #MSKWAJ_COMP_LZH
*/
unsigned short comp_type;
/** The offset in the file where the compressed data stream begins */
off_t data_offset;
/** Flags indicating which optional headers were included. */
int headers;
/** The amount of uncompressed data in the file, or 0 if not present. */
off_t length;
/** output filename, or NULL if not present */
char *filename;
/** extra uncompressed data (usually text) in the header.
* This data can contain nulls so use extra_length to get the size.
*/
char *extra;
/** length of extra uncompressed data in the header */
unsigned short extra_length;
};
/**
* A compressor for the KWAJ file format.
*
* All fields are READ ONLY.
*
* @see mspack_create_kwaj_compressor(), mspack_destroy_kwaj_compressor()
*/
struct mskwaj_compressor {
/**
* Reads an input file and creates a compressed output file in the
* KWAJ compressed file format. The KWAJ compression format is quick
* but gives poor compression. It is possible for the compressed output
* file to be larger than the input file.
*
* @param self a self-referential pointer to the mskwaj_compressor
* instance being called
* @param input the name of the file to compressed. This is passed
* passed directly to mspack_system::open()
* @param output the name of the file to write compressed data to.
* This is passed directly to mspack_system::open().
* @param length the length of the uncompressed file, or -1 to indicate
* that this should be determined automatically by using
* mspack_system::seek() on the input file.
* @return an error code, or MSPACK_ERR_OK if successful
* @see set_param()
*/
int (*compress)(struct mskwaj_compressor *self,
const char *input,
const char *output,
off_t length);
/**
* Sets an KWAJ compression engine parameter.
*
* The following parameters are defined:
*
* - #MSKWAJC_PARAM_COMP_TYPE: the compression method to use. Must
* be one of #MSKWAJC_COMP_NONE, #MSKWAJC_COMP_XOR, #MSKWAJ_COMP_SZDD
* or #MSKWAJ_COMP_LZH. The default is #MSKWAJ_COMP_LZH.
*
* - #MSKWAJC_PARAM_INCLUDE_LENGTH: a boolean; should the compressed
* output file should include the uncompressed length of the input
* file in the header? This adds 4 bytes to the size of the output
* file. A value of zero says "no", non-zero says "yes". The default
* is "no".
*
* @param self a self-referential pointer to the mskwaj_compressor
* instance being called
* @param param the parameter to set
* @param value the value to set the parameter to
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if there
* is a problem with either parameter or value.
* @see generate()
*/
int (*set_param)(struct mskwaj_compressor *self,
int param,
int value);
/**
* Sets the original filename of the file before compression,
* which will be stored in the header of the output file.
*
* The filename should be a null-terminated string, it must be an
* MS-DOS "8.3" type filename (up to 8 bytes for the filename, then
* optionally a "." and up to 3 bytes for a filename extension).
*
* If NULL is passed as the filename, no filename is included in the
* header. This is the default.
*
* @param self a self-referential pointer to the mskwaj_compressor
* instance being called
* @param filename the original filename to use
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if the
* filename is too long
*/
int (*set_filename)(struct mskwaj_compressor *self,
const char *filename);
/**
* Sets arbitrary data that will be stored in the header of the
* output file, uncompressed. It can be up to roughly 64 kilobytes,
* as the overall size of the header must not exceed 65535 bytes.
* The data can contain null bytes if desired.
*
* If NULL is passed as the data pointer, or zero is passed as the
* length, no extra data is included in the header. This is the
* default.
*
* @param self a self-referential pointer to the mskwaj_compressor
* instance being called
* @param data a pointer to the data to be stored in the header
* @param bytes the length of the data in bytes
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS extra data
* is too long
*/
int (*set_extra_data)(struct mskwaj_compressor *self,
void *data,
size_t bytes);
/**
* Returns the error code set by the most recently called method.
*
* @param self a self-referential pointer to the mskwaj_compressor
* instance being called
* @return the most recent error code
* @see compress()
*/
int (*last_error)(struct mschm_decompressor *self);
};
/**
* A decompressor for KWAJ compressed files.
*
* All fields are READ ONLY.
*
* @see mspack_create_kwaj_decompressor(), mspack_destroy_kwaj_decompressor()
*/
struct mskwaj_decompressor {
/**
* Opens a KWAJ file and reads the header.
*
* If the file opened is a valid KWAJ file, all headers will be read and
* a mskwajd_header structure will be returned.
*
* In the case of an error occuring, NULL is returned and the error code
* is available from last_error().
*
* The filename pointer should be considered "in use" until close() is
* called on the KWAJ file.
*
* @param self a self-referential pointer to the mskwaj_decompressor
* instance being called
* @param filename the filename of the KWAJ compressed file. This is
* passed directly to mspack_system::open().
* @return a pointer to a mskwajd_header structure, or NULL on failure
* @see close()
*/
struct mskwajd_header *(*open)(struct mskwaj_decompressor *self,
const char *filename);
/**
* Closes a previously opened KWAJ file.
*
* This closes a KWAJ file and frees the mskwajd_header associated
* with it. The KWAJ header pointer is now invalid and cannot be
* used again.
*
* @param self a self-referential pointer to the mskwaj_decompressor
* instance being called
* @param kwaj the KWAJ file to close
* @see open()
*/
void (*close)(struct mskwaj_decompressor *self,
struct mskwajd_header *kwaj);
/**
* Extracts the compressed data from a KWAJ file.
*
* This decompresses the compressed KWAJ data stream and writes it to
* an output file.
*
* @param self a self-referential pointer to the mskwaj_decompressor
* instance being called
* @param kwaj the KWAJ file to extract data from
* @param filename the filename to write the decompressed data to. This
* is passed directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*extract)(struct mskwaj_decompressor *self,
struct mskwajd_header *kwaj,
const char *filename);
/**
* Decompresses an KWAJ file to an output file in one step.
*
* This opens an KWAJ file as input, reads the header, then decompresses
* the compressed data immediately to an output file, finally closing
* both the input and output file. It is more convenient to use than
* open() then extract() then close(), if you do not need to know the
* KWAJ output size or output filename.
*
* @param self a self-referential pointer to the mskwaj_decompressor
* instance being called
* @param input the filename of the input KWAJ file. This is passed
* directly to mspack_system::open().
* @param output the filename to write the decompressed data to. This
* is passed directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*decompress)(struct mskwaj_decompressor *self,
const char *input,
const char *output);
/**
* Returns the error code set by the most recently called method.
*
* This is useful for open() which does not return an
* error code directly.
*
* @param self a self-referential pointer to the mskwaj_decompressor
* instance being called
* @return the most recent error code
* @see open(), search()
*/
int (*last_error)(struct mskwaj_decompressor *self);
};
/* --- support for .LZX (Offline Address Book) file format ----------------- */
/**
* A compressor for the Offline Address Book (OAB) format.
*
* All fields are READ ONLY.
*
* @see mspack_create_oab_compressor(), mspack_destroy_oab_compressor()
*/
struct msoab_compressor {
/**
* Compress a full OAB file.
*
* The input file will be read and the compressed contents written to the
* output file.
*
* @param self a self-referential pointer to the msoab_decompressor
* instance being called
* @param input the filename of the input file. This is passed
* directly to mspack_system::open().
* @param output the filename of the output file. This is passed
* directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*compress) (struct msoab_compressor *self,
const char *input,
const char *output);
/**
* Generate a compressed incremental OAB patch file.
*
* The two uncompressed files "input" and "base" will be read, and an
* incremental patch to generate "input" from "base" will be written to
* the output file.
*
* @param self a self-referential pointer to the msoab_compressor
* instance being called
* @param input the filename of the input file containing the new
* version of its contents. This is passed directly
* to mspack_system::open().
* @param base the filename of the original base file containing
* the old version of its contents, against which the
* incremental patch shall generated. This is passed
* directly to mspack_system::open().
* @param output the filename of the output file. This is passed
* directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*compress_incremental) (struct msoab_compressor *self,
const char *input,
const char *base,
const char *output);
};
/**
* A decompressor for .LZX (Offline Address Book) files
*
* All fields are READ ONLY.
*
* @see mspack_create_oab_decompressor(), mspack_destroy_oab_decompressor()
*/
struct msoab_decompressor {
/**
* Decompresses a full Offline Address Book file.
*
* If the input file is a valid compressed Offline Address Book file,
* it will be read and the decompressed contents will be written to
* the output file.
*
* @param self a self-referential pointer to the msoab_decompressor
* instance being called
* @param input the filename of the input file. This is passed
* directly to mspack_system::open().
* @param output the filename of the output file. This is passed
* directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*decompress) (struct msoab_decompressor *self,
const char *input,
const char *output);
/**
* Decompresses an Offline Address Book with an incremental patch file.
*
* This requires both a full UNCOMPRESSED Offline Address Book file to
* act as the "base", and a compressed incremental patch file as input.
* If the input file is valid, it will be decompressed with reference to
* the base file, and the decompressed contents will be written to the
* output file.
*
* There is no way to tell what the right base file is for the given
* incremental patch, but if you get it wrong, this will usually result
* in incorrect data being decompressed, which will then fail a checksum
* test.
*
* @param self a self-referential pointer to the msoab_decompressor
* instance being called
* @param input the filename of the input file. This is passed
* directly to mspack_system::open().
* @param base the filename of the base file to which the
* incremental patch shall be applied. This is passed
* directly to mspack_system::open().
* @param output the filename of the output file. This is passed
* directly to mspack_system::open().
* @return an error code, or MSPACK_ERR_OK if successful
*/
int (*decompress_incremental) (struct msoab_decompressor *self,
const char *input,
const char *base,
const char *output);
/**
* Sets an OAB decompression engine parameter. Available only in OAB
* decompressor version 2 and above.
*
* - #MSOABD_PARAM_DECOMPBUF: How many bytes should be used as an input
* buffer by decompressors? The minimum value is 16. The default value
* is 4096.
*
* @param self a self-referential pointer to the msoab_decompressor
* instance being called
* @param param the parameter to set
* @param value the value to set the parameter to
* @return MSPACK_ERR_OK if all is OK, or MSPACK_ERR_ARGS if there
* is a problem with either parameter or value.
*/
int (*set_param)(struct msoab_decompressor *self,
int param,
int value);
};
/** msoab_decompressor::set_param() parameter: size of decompression buffer */
#define MSOABD_PARAM_DECOMPBUF (0)
#ifdef __cplusplus
}
#endif
#endif