/**
* \file lzma/base.h
* \brief Data types and functions used in many places in liblzma API
*/
/*
* Author: Lasse Collin
*
* This file has been put into the public domain.
* You can do whatever you want with this file.
*
* See ../lzma.h for information about liblzma as a whole.
*/
#ifndef LZMA_H_INTERNAL
# error Never include this file directly. Use <lzma.h> instead.
#endif
/**
* \brief Boolean
*
* This is here because C89 doesn't have stdbool.h. To set a value for
* variables having type lzma_bool, you can use
* - C99's `true' and `false' from stdbool.h;
* - C++'s internal `true' and `false'; or
* - integers one (true) and zero (false).
*/
typedef unsigned char lzma_bool;
/**
* \brief Type of reserved enumeration variable in structures
*
* To avoid breaking library ABI when new features are added, several
* structures contain extra variables that may be used in future. Since
* sizeof(enum) can be different than sizeof(int), and sizeof(enum) may
* even vary depending on the range of enumeration constants, we specify
* a separate type to be used for reserved enumeration variables. All
* enumeration constants in liblzma API will be non-negative and less
* than 128, which should guarantee that the ABI won't break even when
* new constants are added to existing enumerations.
*/
typedef enum {
LZMA_RESERVED_ENUM = 0
} lzma_reserved_enum;
/**
* \brief Return values used by several functions in liblzma
*
* Check the descriptions of specific functions to find out which return
* values they can return. With some functions the return values may have
* more specific meanings than described here; those differences are
* described per-function basis.
*/
typedef enum {
LZMA_OK = 0,
/**<
* \brief Operation completed successfully
*/
LZMA_STREAM_END = 1,
/**<
* \brief End of stream was reached
*
* In encoder, LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, or
* LZMA_FINISH was finished. In decoder, this indicates
* that all the data was successfully decoded.
*
* In all cases, when LZMA_STREAM_END is returned, the last
* output bytes should be picked from strm->next_out.
*/
LZMA_NO_CHECK = 2,
/**<
* \brief Input stream has no integrity check
*
* This return value can be returned only if the
* LZMA_TELL_NO_CHECK flag was used when initializing
* the decoder. LZMA_NO_CHECK is just a warning, and
* the decoding can be continued normally.
*
* It is possible to call lzma_get_check() immediately after
* lzma_code has returned LZMA_NO_CHECK. The result will
* naturally be LZMA_CHECK_NONE, but the possibility to call
* lzma_get_check() may be convenient in some applications.
*/
LZMA_UNSUPPORTED_CHECK = 3,
/**<
* \brief Cannot calculate the integrity check
*
* The usage of this return value is different in encoders
* and decoders.
*
* Encoders can return this value only from the initialization
* function. If initialization fails with this value, the
* encoding cannot be done, because there's no way to produce
* output with the correct integrity check.
*
* Decoders can return this value only from lzma_code() and
* only if the LZMA_TELL_UNSUPPORTED_CHECK flag was used when
* initializing the decoder. The decoding can still be
* continued normally even if the check type is unsupported,
* but naturally the check will not be validated, and possible
* errors may go undetected.
*
* With decoder, it is possible to call lzma_get_check()
* immediately after lzma_code() has returned
* LZMA_UNSUPPORTED_CHECK. This way it is possible to find
* out what the unsupported Check ID was.
*/
LZMA_GET_CHECK = 4,
/**<
* \brief Integrity check type is now available
*
* This value can be returned only by the lzma_code() function
* and only if the decoder was initialized with the
* LZMA_TELL_ANY_CHECK flag. LZMA_GET_CHECK tells the
* application that it may now call lzma_get_check() to find
* out the Check ID. This can be used, for example, to
* implement a decoder that accepts only files that have
* strong enough integrity check.
*/
LZMA_MEM_ERROR = 5,
/**<
* \brief Cannot allocate memory
*
* Memory allocation failed, or the size of the allocation
* would be greater than SIZE_MAX.
*
* Due to internal implementation reasons, the coding cannot
* be continued even if more memory were made available after
* LZMA_MEM_ERROR.
*/
LZMA_MEMLIMIT_ERROR = 6,
/**
* \brief Memory usage limit was reached
*
* Decoder would need more memory than allowed by the
* specified memory usage limit. To continue decoding,
* the memory usage limit has to be increased with
* lzma_memlimit_set().
*/
LZMA_FORMAT_ERROR = 7,
/**<
* \brief File format not recognized
*
* The decoder did not recognize the input as supported file
* format. This error can occur, for example, when trying to
* decode .lzma format file with lzma_stream_decoder,
* because lzma_stream_decoder accepts only the .xz format.
*/
LZMA_OPTIONS_ERROR = 8,
/**<
* \brief Invalid or unsupported options
*
* Invalid or unsupported options, for example
* - unsupported filter(s) or filter options; or
* - reserved bits set in headers (decoder only).
*
* Rebuilding liblzma with more features enabled, or
* upgrading to a newer version of liblzma may help.
*/
LZMA_DATA_ERROR = 9,
/**<
* \brief Data is corrupt
*
* The usage of this return value is different in encoders
* and decoders. In both encoder and decoder, the coding
* cannot continue after this error.
*
* Encoders return this if size limits of the target file
* format would be exceeded. These limits are huge, thus
* getting this error from an encoder is mostly theoretical.
* For example, the maximum compressed and uncompressed
* size of a .xz Stream is roughly 8 EiB (2^63 bytes).
*
* Decoders return this error if the input data is corrupt.
* This can mean, for example, invalid CRC32 in headers
* or invalid check of uncompressed data.
*/
LZMA_BUF_ERROR = 10,
/**<
* \brief No progress is possible
*
* This error code is returned when the coder cannot consume
* any new input and produce any new output. The most common
* reason for this error is that the input stream being
* decoded is truncated or corrupt.
*
* This error is not fatal. Coding can be continued normally
* by providing more input and/or more output space, if
* possible.
*
* Typically the first call to lzma_code() that can do no
* progress returns LZMA_OK instead of LZMA_BUF_ERROR. Only
* the second consecutive call doing no progress will return
* LZMA_BUF_ERROR. This is intentional.
*
* With zlib, Z_BUF_ERROR may be returned even if the
* application is doing nothing wrong, so apps will need
* to handle Z_BUF_ERROR specially. The above hack
* guarantees that liblzma never returns LZMA_BUF_ERROR
* to properly written applications unless the input file
* is truncated or corrupt. This should simplify the
* applications a little.
*/
LZMA_PROG_ERROR = 11,
/**<
* \brief Programming error
*
* This indicates that the arguments given to the function are
* invalid or the internal state of the decoder is corrupt.
* - Function arguments are invalid or the structures
* pointed by the argument pointers are invalid
* e.g. if strm->next_out has been set to NULL and
* strm->avail_out > 0 when calling lzma_code().
* - lzma_* functions have been called in wrong order
* e.g. lzma_code() was called right after lzma_end().
* - If errors occur randomly, the reason might be flaky
* hardware.
*
* If you think that your code is correct, this error code
* can be a sign of a bug in liblzma. See the documentation
* how to report bugs.
*/
} lzma_ret;
/**
* \brief The `action' argument for lzma_code()
*
* After the first use of LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, or LZMA_FINISH,
* the same `action' must is used until lzma_code() returns LZMA_STREAM_END.
* Also, the amount of input (that is, strm->avail_in) must not be modified
* by the application until lzma_code() returns LZMA_STREAM_END. Changing the
* `action' or modifying the amount of input will make lzma_code() return
* LZMA_PROG_ERROR.
*/
typedef enum {
LZMA_RUN = 0,
/**<
* \brief Continue coding
*
* Encoder: Encode as much input as possible. Some internal
* buffering will probably be done (depends on the filter
* chain in use), which causes latency: the input used won't
* usually be decodeable from the output of the same
* lzma_code() call.
*
* Decoder: Decode as much input as possible and produce as
* much output as possible.
*/
LZMA_SYNC_FLUSH = 1,
/**<
* \brief Make all the input available at output
*
* Normally the encoder introduces some latency.
* LZMA_SYNC_FLUSH forces all the buffered data to be
* available at output without resetting the internal
* state of the encoder. This way it is possible to use
* compressed stream for example for communication over
* network.
*
* Only some filters support LZMA_SYNC_FLUSH. Trying to use
* LZMA_SYNC_FLUSH with filters that don't support it will
* make lzma_code() return LZMA_OPTIONS_ERROR. For example,
* LZMA1 doesn't support LZMA_SYNC_FLUSH but LZMA2 does.
*
* Using LZMA_SYNC_FLUSH very often can dramatically reduce
* the compression ratio. With some filters (for example,
* LZMA2), fine-tuning the compression options may help
* mitigate this problem significantly (for example,
* match finder with LZMA2).
*
* Decoders don't support LZMA_SYNC_FLUSH.
*/
LZMA_FULL_FLUSH = 2,
/**<
* \brief Finish encoding of the current Block
*
* All the input data going to the current Block must have
* been given to the encoder (the last bytes can still be
* pending in* next_in). Call lzma_code() with LZMA_FULL_FLUSH
* until it returns LZMA_STREAM_END. Then continue normally
* with LZMA_RUN or finish the Stream with LZMA_FINISH.
*
* This action is currently supported only by Stream encoder
* and easy encoder (which uses Stream encoder). If there is
* no unfinished Block, no empty Block is created.
*/
LZMA_FINISH = 3
/**<
* \brief Finish the coding operation
*
* All the input data must have been given to the encoder
* (the last bytes can still be pending in next_in).
* Call lzma_code() with LZMA_FINISH until it returns
* LZMA_STREAM_END. Once LZMA_FINISH has been used,
* the amount of input must no longer be changed by
* the application.
*
* When decoding, using LZMA_FINISH is optional unless the
* LZMA_CONCATENATED flag was used when the decoder was
* initialized. When LZMA_CONCATENATED was not used, the only
* effect of LZMA_FINISH is that the amount of input must not
* be changed just like in the encoder.
*/
} lzma_action;
/**
* \brief Custom functions for memory handling
*
* A pointer to lzma_allocator may be passed via lzma_stream structure
* to liblzma, and some advanced functions take a pointer to lzma_allocator
* as a separate function argument. The library will use the functions
* specified in lzma_allocator for memory handling instead of the default
* malloc() and free(). C++ users should note that the custom memory
* handling functions must not throw exceptions.
*
* Single-threaded mode only: liblzma doesn't make an internal copy of
* lzma_allocator. Thus, it is OK to change these function pointers in
* the middle of the coding process, but obviously it must be done
* carefully to make sure that the replacement `free' can deallocate
* memory allocated by the earlier `alloc' function(s).
*
* Multithreaded mode: liblzma might internally store pointers to the
* lzma_allocator given via the lzma_stream structure. The application
* must not change the allocator pointer in lzma_stream or the contents
* of the pointed lzma_allocator structure until lzma_end() has been used
* to free the memory associated with that lzma_stream. The allocation
* functions might be called simultaneously from multiple threads, and
* thus they must be thread safe.
*/
typedef struct {
/**
* \brief Pointer to a custom memory allocation function
*
* If you don't want a custom allocator, but still want
* custom free(), set this to NULL and liblzma will use
* the standard malloc().
*
* \param opaque lzma_allocator.opaque (see below)
* \param nmemb Number of elements like in calloc(). liblzma
* will always set nmemb to 1, so it is safe to
* ignore nmemb in a custom allocator if you like.
* The nmemb argument exists only for
* compatibility with zlib and libbzip2.
* \param size Size of an element in bytes.
* liblzma never sets this to zero.
*
* \return Pointer to the beginning of a memory block of
* `size' bytes, or NULL if allocation fails
* for some reason. When allocation fails, functions
* of liblzma return LZMA_MEM_ERROR.
*
* The allocator should not waste time zeroing the allocated buffers.
* This is not only about speed, but also memory usage, since the
* operating system kernel doesn't necessarily allocate the requested
* memory in physical memory until it is actually used. With small
* input files, liblzma may actually need only a fraction of the
* memory that it requested for allocation.
*
* \note LZMA_MEM_ERROR is also used when the size of the
* allocation would be greater than SIZE_MAX. Thus,
* don't assume that the custom allocator must have
* returned NULL if some function from liblzma
* returns LZMA_MEM_ERROR.
*/
void *(LZMA_API_CALL *alloc)(void *opaque, size_t nmemb, size_t size);
/**
* \brief Pointer to a custom memory freeing function
*
* If you don't want a custom freeing function, but still
* want a custom allocator, set this to NULL and liblzma
* will use the standard free().
*
* \param opaque lzma_allocator.opaque (see below)
* \param ptr Pointer returned by lzma_allocator.alloc(),
* or when it is set to NULL, a pointer returned
* by the standard malloc().
*/
void (LZMA_API_CALL *free)(void *opaque, void *ptr);
/**
* \brief Pointer passed to .alloc() and .free()
*
* opaque is passed as the first argument to lzma_allocator.alloc()
* and lzma_allocator.free(). This intended to ease implementing
* custom memory allocation functions for use with liblzma.
*
* If you don't need this, you should set this to NULL.
*/
void *opaque;
} lzma_allocator;
/**
* \brief Internal data structure
*
* The contents of this structure is not visible outside the library.
*/
typedef struct lzma_internal_s lzma_internal;
/**
* \brief Passing data to and from liblzma
*
* The lzma_stream structure is used for
* - passing pointers to input and output buffers to liblzma;
* - defining custom memory hander functions; and
* - holding a pointer to coder-specific internal data structures.
*
* Typical usage:
*
* - After allocating lzma_stream (on stack or with malloc()), it must be
* initialized to LZMA_STREAM_INIT (see LZMA_STREAM_INIT for details).
*
* - Initialize a coder to the lzma_stream, for example by using
* lzma_easy_encoder() or lzma_auto_decoder(). Some notes:
* - In contrast to zlib, strm->next_in and strm->next_out are
* ignored by all initialization functions, thus it is safe
* to not initialize them yet.
* - The initialization functions always set strm->total_in and
* strm->total_out to zero.
* - If the initialization function fails, no memory is left allocated
* that would require freeing with lzma_end() even if some memory was
* associated with the lzma_stream structure when the initialization
* function was called.
*
* - Use lzma_code() to do the actual work.
*
* - Once the coding has been finished, the existing lzma_stream can be
* reused. It is OK to reuse lzma_stream with different initialization
* function without calling lzma_end() first. Old allocations are
* automatically freed.
*
* - Finally, use lzma_end() to free the allocated memory. lzma_end() never
* frees the lzma_stream structure itself.
*
* Application may modify the values of total_in and total_out as it wants.
* They are updated by liblzma to match the amount of data read and
* written, but aren't used for anything else.
*/
typedef struct {
const uint8_t *next_in; /**< Pointer to the next input byte. */
size_t avail_in; /**< Number of available input bytes in next_in. */
uint64_t total_in; /**< Total number of bytes read by liblzma. */
uint8_t *next_out; /**< Pointer to the next output position. */
size_t avail_out; /**< Amount of free space in next_out. */
uint64_t total_out; /**< Total number of bytes written by liblzma. */
/**
* \brief Custom memory allocation functions
*
* In most cases this is NULL which makes liblzma use
* the standard malloc() and free().
*
* \note In 5.0.x this is not a const pointer.
*/
const lzma_allocator *allocator;
/** Internal state is not visible to applications. */
lzma_internal *internal;
/*
* Reserved space to allow possible future extensions without
* breaking the ABI. Excluding the initialization of this structure,
* you should not touch these, because the names of these variables
* may change.
*/
void *reserved_ptr1;
void *reserved_ptr2;
void *reserved_ptr3;
void *reserved_ptr4;
uint64_t reserved_int1;
uint64_t reserved_int2;
size_t reserved_int3;
size_t reserved_int4;
lzma_reserved_enum reserved_enum1;
lzma_reserved_enum reserved_enum2;
} lzma_stream;
/**
* \brief Initialization for lzma_stream
*
* When you declare an instance of lzma_stream, you can immediately
* initialize it so that initialization functions know that no memory
* has been allocated yet:
*
* lzma_stream strm = LZMA_STREAM_INIT;
*
* If you need to initialize a dynamically allocated lzma_stream, you can use
* memset(strm_pointer, 0, sizeof(lzma_stream)). Strictly speaking, this
* violates the C standard since NULL may have different internal
* representation than zero, but it should be portable enough in practice.
* Anyway, for maximum portability, you can use something like this:
*
* lzma_stream tmp = LZMA_STREAM_INIT;
* *strm = tmp;
*/
#define LZMA_STREAM_INIT \
{ NULL, 0, 0, NULL, 0, 0, NULL, NULL, \
NULL, NULL, NULL, NULL, 0, 0, 0, 0, \
LZMA_RESERVED_ENUM, LZMA_RESERVED_ENUM }
/**
* \brief Encode or decode data
*
* Once the lzma_stream has been successfully initialized (e.g. with
* lzma_stream_encoder()), the actual encoding or decoding is done
* using this function. The application has to update strm->next_in,
* strm->avail_in, strm->next_out, and strm->avail_out to pass input
* to and get output from liblzma.
*
* See the description of the coder-specific initialization function to find
* out what `action' values are supported by the coder.
*/
extern LZMA_API(lzma_ret) lzma_code(lzma_stream *strm, lzma_action action)
lzma_nothrow lzma_attr_warn_unused_result;
/**
* \brief Free memory allocated for the coder data structures
*
* \param strm Pointer to lzma_stream that is at least initialized
* with LZMA_STREAM_INIT.
*
* After lzma_end(strm), strm->internal is guaranteed to be NULL. No other
* members of the lzma_stream structure are touched.
*
* \note zlib indicates an error if application end()s unfinished
* stream structure. liblzma doesn't do this, and assumes that
* application knows what it is doing.
*/
extern LZMA_API(void) lzma_end(lzma_stream *strm) lzma_nothrow;
/**
* \brief Get the memory usage of decoder filter chain
*
* This function is currently supported only when *strm has been initialized
* with a function that takes a memlimit argument. With other functions, you
* should use e.g. lzma_raw_encoder_memusage() or lzma_raw_decoder_memusage()
* to estimate the memory requirements.
*
* This function is useful e.g. after LZMA_MEMLIMIT_ERROR to find out how big
* the memory usage limit should have been to decode the input. Note that
* this may give misleading information if decoding .xz Streams that have
* multiple Blocks, because each Block can have different memory requirements.
*
* \return How much memory is currently allocated for the filter
* decoders. If no filter chain is currently allocated,
* some non-zero value is still returned, which is less than
* or equal to what any filter chain would indicate as its
* memory requirement.
*
* If this function isn't supported by *strm or some other error
* occurs, zero is returned.
*/
extern LZMA_API(uint64_t) lzma_memusage(const lzma_stream *strm)
lzma_nothrow lzma_attr_pure;
/**
* \brief Get the current memory usage limit
*
* This function is supported only when *strm has been initialized with
* a function that takes a memlimit argument.
*
* \return On success, the current memory usage limit is returned
* (always non-zero). On error, zero is returned.
*/
extern LZMA_API(uint64_t) lzma_memlimit_get(const lzma_stream *strm)
lzma_nothrow lzma_attr_pure;
/**
* \brief Set the memory usage limit
*
* This function is supported only when *strm has been initialized with
* a function that takes a memlimit argument.
*
* \return - LZMA_OK: New memory usage limit successfully set.
* - LZMA_MEMLIMIT_ERROR: The new limit is too small.
* The limit was not changed.
* - LZMA_PROG_ERROR: Invalid arguments, e.g. *strm doesn't
* support memory usage limit or memlimit was zero.
*/
extern LZMA_API(lzma_ret) lzma_memlimit_set(
lzma_stream *strm, uint64_t memlimit) lzma_nothrow;
