common.h File Reference

Definitions common to the whole liblzma library. More...

#include "sysdefs.h"
#include "mythread.h"
#include "tuklib_integer.h"
#include "lzma.h"

Go to the source code of this file.

Data Structures
struct	lzma_filter_info_s
struct	lzma_next_coder_s
	Hold data and function pointers of the next filter in the chain. More...
struct	lzma_internal_s

Macros
#define	LZMA_API_EXPORT
#define	LZMA_API(type)
#define	lzma_has_attribute(attr)
#define	likely(expr)
#define	unlikely(expr)
#define	LZMA_BUFFER_SIZE   4096
	Size of temporary buffers needed in some filters.
#define	LZMA_THREADS_MAX   16384
#define	LZMA_MEMUSAGE_BASE   (UINT64_C(1) << 15)
#define	LZMA_FILTER_RESERVED_START   (LZMA_VLI_C(1) << 62)
#define	LZMA_SUPPORTED_FLAGS
#define	LZMA_ACTION_MAX   ((unsigned int)(LZMA_FULL_BARRIER))
	Largest valid lzma_action value as unsigned integer.
#define	LZMA_TIMED_OUT   LZMA_RET_INTERNAL1
#define	LZMA_INDEX_DETECTED   LZMA_RET_INTERNAL2
#define	LZMA_NEXT_CODER_INIT
	Macro to initialize lzma_next_coder structure.
#define	return_if_error(expr)
	Return if expression doesn't evaluate to LZMA_OK.
#define	lzma_next_coder_init(func, next, allocator)
#define	lzma_next_strm_init(func, strm, ...)

Typedefs
typedef struct lzma_next_coder_s	lzma_next_coder
typedef struct lzma_filter_info_s	lzma_filter_info
typedef lzma_ret(*	lzma_init_function) (lzma_next_coder *next, const lzma_allocator *allocator, const lzma_filter_info *filters)
	Type of a function used to initialize a filter encoder or decoder.
typedef lzma_ret(*	lzma_code_function) (void *coder, const lzma_allocator *allocator, const uint8_t *restrict in, size_t *restrict in_pos, size_t in_size, uint8_t *restrict out, size_t *restrict out_pos, size_t out_size, lzma_action action)
typedef void(*	lzma_end_function) (void *coder, const lzma_allocator *allocator)
	Type of a function to free the memory allocated for the coder.

Functions
void *	lzma_alloc (size_t size, const lzma_allocator *allocator) lzma_attribute((__malloc__)) lzma_attr_alloc_size(1)
	Allocates memory.
void *	lzma_attribute ((__malloc__)) lzma_attr_alloc_size(1) lzma_alloc_zero(size_t size
void	lzma_free (void *ptr, const lzma_allocator *allocator)
	Frees memory.
lzma_ret	lzma_strm_init (lzma_stream *strm)
lzma_ret	lzma_next_filter_init (lzma_next_coder *next, const lzma_allocator *allocator, const lzma_filter_info *filters)
lzma_ret	lzma_next_filter_update (lzma_next_coder *next, const lzma_allocator *allocator, const lzma_filter *reversed_filters)
void	lzma_next_end (lzma_next_coder *next, const lzma_allocator *allocator)
size_t	lzma_bufcpy (const uint8_t *restrict in, size_t *restrict in_pos, size_t in_size, uint8_t *restrict out, size_t *restrict out_pos, size_t out_size)

Variables
void const lzma_allocator *	allocator

Detailed Description

Definitions common to the whole liblzma library.

Macro Definition Documentation

likely

#define likely

(

expr

)

Value:

(expr)

LZMA_ACTION_MAX

#define LZMA_ACTION_MAX   ((unsigned int)(LZMA_FULL_BARRIER))

Largest valid lzma_action value as unsigned integer.

LZMA_API

#define LZMA_API

(

type

)

Value:

LZMA_API_EXPORT type LZMA_API_CALL

LZMA_API_EXPORT

#define LZMA_API_EXPORT

LZMA_BUFFER_SIZE

#define LZMA_BUFFER_SIZE   4096

Size of temporary buffers needed in some filters.

LZMA_FILTER_RESERVED_START

#define LZMA_FILTER_RESERVED_START   (LZMA_VLI_C(1) << 62)

Start of internal Filter ID space. These IDs must never be used in Streams.

lzma_has_attribute

#define lzma_has_attribute

(

attr

)

Value:

0

LZMA_INDEX_DETECTED

#define LZMA_INDEX_DETECTED   LZMA_RET_INTERNAL2

Special return value (lzma_ret) for use in stream_decoder_mt.c to indicate Index was detected instead of a Block Header.

LZMA_MEMUSAGE_BASE

#define LZMA_MEMUSAGE_BASE   (UINT64_C(1) << 15)

Starting value for memory usage estimates. Instead of calculating size of every structure and taking into account malloc() overhead etc., we add a base size to all memory usage estimates. It's not very accurate but should be easily good enough.

LZMA_NEXT_CODER_INIT

#define LZMA_NEXT_CODER_INIT

Value:

    (lzma_next_coder){ \
        .coder = NULL, \
        .init = (uintptr_t)(NULL), \
        .id = LZMA_VLI_UNKNOWN, \
        .code = NULL, \
        .end = NULL, \
        .get_progress = NULL, \
        .get_check = NULL, \
        .memconfig = NULL, \
        .update = NULL, \
        .set_out_limit = NULL, \
    }

Macro to initialize lzma_next_coder structure.

lzma_next_coder_init

#define lzma_next_coder_init	(		func,
			next,
			allocator )

Value:

do { \
    if ((uintptr_t)(func) != (next)->init) \
        lzma_next_end(next, allocator); \
    (next)->init = (uintptr_t)(func); \
} while (0)

If next isn't already initialized, free the previous coder. Then mark that next is possibly initialized for the coder using this macro. "Possibly" means that if e.g. allocation of next->coder fails, the structure isn't actually initialized for this coder, but leaving next->init to func is still OK.

lzma_next_strm_init

#define lzma_next_strm_init	(		func,
			strm,
			... )

Value:

do { \
    return_if_error(lzma_strm_init(strm)); \
    const lzma_ret ret_ = func(&(strm)->internal->next, \
            (strm)->allocator, __VA_ARGS__); \
    if (ret_ != LZMA_OK) { \
        lzma_end(strm); \
        return ret_; \
    } \
} while (0)

Initializes lzma_strm and calls func() to initialize strm->internal->next. (The function being called will use lzma_next_coder_init()). If initialization fails, memory that wasn't freed by func() is freed along strm->internal.

LZMA_SUPPORTED_FLAGS

#define LZMA_SUPPORTED_FLAGS

Value:

    ( LZMA_TELL_NO_CHECK \
    | LZMA_TELL_UNSUPPORTED_CHECK \
    | LZMA_TELL_ANY_CHECK \
    | LZMA_IGNORE_CHECK \
    | LZMA_CONCATENATED \
    | LZMA_FAIL_FAST )

Supported flags that can be passed to lzma_stream_decoder(), lzma_auto_decoder(), or lzma_stream_decoder_mt().

LZMA_THREADS_MAX

#define LZMA_THREADS_MAX   16384

Maximum number of worker threads within one multithreaded component. The limit exists solely to make it simpler to prevent integer overflows when allocating structures etc. This should be big enough for now... the code won't scale anywhere close to this number anyway.

LZMA_TIMED_OUT

#define LZMA_TIMED_OUT   LZMA_RET_INTERNAL1

Special return value (lzma_ret) to indicate that a timeout was reached and lzma_code() must not return LZMA_BUF_ERROR. This is converted to LZMA_OK in lzma_code().

return_if_error

#define return_if_error

(

expr

)

Value:

do { \
    const lzma_ret ret_ = (expr); \
    if (ret_ != LZMA_OK) \
        return ret_; \
} while (0)

Return if expression doesn't evaluate to LZMA_OK.

There are several situations where we want to return immediately with the value of expr if it isn't LZMA_OK. This macro shortens the code a little.

unlikely

#define unlikely

(

expr

)

Value:

(expr)

Typedef Documentation

lzma_code_function

typedef lzma_ret(* lzma_code_function) (void *coder, const lzma_allocator *allocator, const uint8_t *restrict in, size_t *restrict in_pos, size_t in_size, uint8_t *restrict out, size_t *restrict out_pos, size_t out_size, lzma_action action)

Type of a function to do some kind of coding work (filters, Stream, Block encoders/decoders etc.). Some special coders use don't use both input and output buffers, but for simplicity they still use this same function prototype.

lzma_end_function

typedef void(* lzma_end_function) (void *coder, const lzma_allocator *allocator)

Type of a function to free the memory allocated for the coder.

lzma_filter_info

typedef struct lzma_filter_info_s lzma_filter_info

lzma_init_function

typedef lzma_ret(* lzma_init_function) (lzma_next_coder *next, const lzma_allocator *allocator, const lzma_filter_info *filters)

Type of a function used to initialize a filter encoder or decoder.

lzma_next_coder

typedef struct lzma_next_coder_s lzma_next_coder

Function Documentation

lzma_alloc()

void * lzma_alloc ( size_t size, const lzma_allocator * allocator )

extern

Allocates memory.

lzma_attribute()

void * lzma_attribute ( (__malloc__) )

extern

Allocates memory and zeroes it (like calloc()). This can be faster than lzma_alloc() + memzero() while being backward compatible with custom allocators.

lzma_bufcpy()

size_t lzma_bufcpy ( const uint8_t *restrict in, size_t *restrict in_pos, size_t in_size, uint8_t *restrict out, size_t *restrict out_pos, size_t out_size )

extern

Copy as much data as possible from in[] to out[] and update *in_pos and *out_pos accordingly. Returns the number of bytes copied.

lzma_free()

void lzma_free ( void * ptr, const lzma_allocator * allocator )

extern

Frees memory.

lzma_next_end()

void lzma_next_end ( lzma_next_coder * next, const lzma_allocator * allocator )

extern

Frees the memory allocated for next->coder either using next->end or, if next->end is NULL, using lzma_free.

lzma_next_filter_init()

lzma_ret lzma_next_filter_init ( lzma_next_coder * next, const lzma_allocator * allocator, const lzma_filter_info * filters )

extern

Initializes the next filter in the chain, if any. This takes care of freeing the memory of previously initialized filter if it is different than the filter being initialized now. This way the actual filter initialization functions don't need to use lzma_next_coder_init macro.

lzma_next_filter_update()

lzma_ret lzma_next_filter_update ( lzma_next_coder * next, const lzma_allocator * allocator, const lzma_filter * reversed_filters )

extern

Update the next filter in the chain, if any. This checks that the application is not trying to change the Filter IDs.

lzma_strm_init()

lzma_ret lzma_strm_init ( lzma_stream * strm )

extern

Allocates strm->internal if it is NULL, and initializes *strm and strm->internal. This function is only called via lzma_next_strm_init macro.

Variable Documentation

allocator

void const lzma_allocator* allocator