(root)/
xz-5.4.5/
src/
liblzma/
common/
common.h
       1  ///////////////////////////////////////////////////////////////////////////////
       2  //
       3  /// \file       common.h
       4  /// \brief      Definitions common to the whole liblzma library
       5  //
       6  //  Author:     Lasse Collin
       7  //
       8  //  This file has been put into the public domain.
       9  //  You can do whatever you want with this file.
      10  //
      11  ///////////////////////////////////////////////////////////////////////////////
      12  
      13  #ifndef LZMA_COMMON_H
      14  #define LZMA_COMMON_H
      15  
      16  #include "sysdefs.h"
      17  #include "mythread.h"
      18  #include "tuklib_integer.h"
      19  
      20  // LZMA_API_EXPORT is used to mark the exported API functions.
      21  // It's used to define the LZMA_API macro.
      22  //
      23  // lzma_attr_visibility_hidden is used for marking *declarations* of extern
      24  // variables that are internal to liblzma (-fvisibility=hidden alone is
      25  // enough to hide the *definitions*). Such markings allow slightly more
      26  // efficient code to accesses those variables in ELF shared libraries.
      27  #if defined(_WIN32) || defined(__CYGWIN__)
      28  #	ifdef DLL_EXPORT
      29  #		define LZMA_API_EXPORT __declspec(dllexport)
      30  #	else
      31  #		define LZMA_API_EXPORT
      32  #	endif
      33  #	define lzma_attr_visibility_hidden
      34  // Don't use ifdef or defined() below.
      35  #elif HAVE_VISIBILITY
      36  #	define LZMA_API_EXPORT __attribute__((__visibility__("default")))
      37  #	define lzma_attr_visibility_hidden \
      38  			__attribute__((__visibility__("hidden")))
      39  #else
      40  #	define LZMA_API_EXPORT
      41  #	define lzma_attr_visibility_hidden
      42  #endif
      43  
      44  #define LZMA_API(type) LZMA_API_EXPORT type LZMA_API_CALL
      45  
      46  #include "lzma.h"
      47  
      48  // This is for detecting modern GCC and Clang attributes
      49  // like __symver__ in GCC >= 10.
      50  #ifdef __has_attribute
      51  #	define lzma_has_attribute(attr) __has_attribute(attr)
      52  #else
      53  #	define lzma_has_attribute(attr) 0
      54  #endif
      55  
      56  // The extra symbol versioning in the C files may only be used when
      57  // building a shared library. If HAVE_SYMBOL_VERSIONS_LINUX is defined
      58  // to 2 then symbol versioning is done only if also PIC is defined.
      59  // By default Libtool defines PIC when building a shared library and
      60  // doesn't define it when building a static library but it can be
      61  // overridden with --with-pic and --without-pic. configure let's rely
      62  // on PIC if neither --with-pic or --without-pic was used.
      63  #if defined(HAVE_SYMBOL_VERSIONS_LINUX) \
      64  		&& (HAVE_SYMBOL_VERSIONS_LINUX == 2 && !defined(PIC))
      65  #	undef HAVE_SYMBOL_VERSIONS_LINUX
      66  #endif
      67  
      68  #ifdef HAVE_SYMBOL_VERSIONS_LINUX
      69  // To keep link-time optimization (LTO, -flto) working with GCC,
      70  // the __symver__ attribute must be used instead of __asm__(".symver ...").
      71  // Otherwise the symbol versions may be lost, resulting in broken liblzma
      72  // that has wrong default versions in the exported symbol list!
      73  // The attribute was added in GCC 10; LTO with older GCC is not supported.
      74  //
      75  // To keep -Wmissing-prototypes happy, use LZMA_SYMVER_API only with function
      76  // declarations (including those with __alias__ attribute) and LZMA_API with
      77  // the function definitions. This means a little bit of silly copy-and-paste
      78  // between declarations and definitions though.
      79  //
      80  // As of GCC 12.2, the __symver__ attribute supports only @ and @@ but the
      81  // very convenient @@@ isn't supported (it's supported by GNU assembler
      82  // since 2000). When using @@ instead of @@@, the internal name must not be
      83  // the same as the external name to avoid problems in some situations. This
      84  // is why "#define foo_52 foo" is needed for the default symbol versions.
      85  //
      86  // __has_attribute is supported before GCC 10 and it is supported in Clang 14
      87  // too (which doesn't support __symver__) so use it to detect if __symver__
      88  // is available. This should be far more reliable than looking at compiler
      89  // version macros as nowadays especially __GNUC__ is defined by many compilers.
      90  #	if lzma_has_attribute(__symver__)
      91  #		define LZMA_SYMVER_API(extnamever, type, intname) \
      92  			extern __attribute__((__symver__(extnamever))) \
      93  					LZMA_API(type) intname
      94  #	else
      95  #		define LZMA_SYMVER_API(extnamever, type, intname) \
      96  			__asm__(".symver " #intname "," extnamever); \
      97  			extern LZMA_API(type) intname
      98  #	endif
      99  #endif
     100  
     101  // MSVC has __forceinline which shouldn't be combined with the inline keyword
     102  // (results in a warning).
     103  //
     104  // GCC 3.1 added always_inline attribute so we don't need to check
     105  // for __GNUC__ version. Similarly, all relevant Clang versions
     106  // support it (at least Clang 3.0.0 does already).
     107  // Other compilers might support too which also support __has_attribute
     108  // (Solaris Studio) so do that check too.
     109  #if defined(_MSC_VER)
     110  #	define lzma_always_inline __forceinline
     111  #elif defined(__GNUC__) || defined(__clang__) || defined(__INTEL_COMPILER) \
     112  		|| lzma_has_attribute(__always_inline__)
     113  #	define lzma_always_inline inline __attribute__((__always_inline__))
     114  #else
     115  #	define lzma_always_inline inline
     116  #endif
     117  
     118  // These allow helping the compiler in some often-executed branches, whose
     119  // result is almost always the same.
     120  #ifdef __GNUC__
     121  #	define likely(expr) __builtin_expect(expr, true)
     122  #	define unlikely(expr) __builtin_expect(expr, false)
     123  #else
     124  #	define likely(expr) (expr)
     125  #	define unlikely(expr) (expr)
     126  #endif
     127  
     128  
     129  /// Size of temporary buffers needed in some filters
     130  #define LZMA_BUFFER_SIZE 4096
     131  
     132  
     133  /// Maximum number of worker threads within one multithreaded component.
     134  /// The limit exists solely to make it simpler to prevent integer overflows
     135  /// when allocating structures etc. This should be big enough for now...
     136  /// the code won't scale anywhere close to this number anyway.
     137  #define LZMA_THREADS_MAX 16384
     138  
     139  
     140  /// Starting value for memory usage estimates. Instead of calculating size
     141  /// of _every_ structure and taking into account malloc() overhead etc., we
     142  /// add a base size to all memory usage estimates. It's not very accurate
     143  /// but should be easily good enough.
     144  #define LZMA_MEMUSAGE_BASE (UINT64_C(1) << 15)
     145  
     146  /// Start of internal Filter ID space. These IDs must never be used
     147  /// in Streams.
     148  #define LZMA_FILTER_RESERVED_START (LZMA_VLI_C(1) << 62)
     149  
     150  
     151  /// Supported flags that can be passed to lzma_stream_decoder(),
     152  /// lzma_auto_decoder(), or lzma_stream_decoder_mt().
     153  #define LZMA_SUPPORTED_FLAGS \
     154  	( LZMA_TELL_NO_CHECK \
     155  	| LZMA_TELL_UNSUPPORTED_CHECK \
     156  	| LZMA_TELL_ANY_CHECK \
     157  	| LZMA_IGNORE_CHECK \
     158  	| LZMA_CONCATENATED \
     159  	| LZMA_FAIL_FAST )
     160  
     161  
     162  /// Largest valid lzma_action value as unsigned integer.
     163  #define LZMA_ACTION_MAX ((unsigned int)(LZMA_FULL_BARRIER))
     164  
     165  
     166  /// Special return value (lzma_ret) to indicate that a timeout was reached
     167  /// and lzma_code() must not return LZMA_BUF_ERROR. This is converted to
     168  /// LZMA_OK in lzma_code().
     169  #define LZMA_TIMED_OUT LZMA_RET_INTERNAL1
     170  
     171  /// Special return value (lzma_ret) for use in stream_decoder_mt.c to
     172  /// indicate Index was detected instead of a Block Header.
     173  #define LZMA_INDEX_DETECTED LZMA_RET_INTERNAL2
     174  
     175  
     176  typedef struct lzma_next_coder_s lzma_next_coder;
     177  
     178  typedef struct lzma_filter_info_s lzma_filter_info;
     179  
     180  
     181  /// Type of a function used to initialize a filter encoder or decoder
     182  typedef lzma_ret (*lzma_init_function)(
     183  		lzma_next_coder *next, const lzma_allocator *allocator,
     184  		const lzma_filter_info *filters);
     185  
     186  /// Type of a function to do some kind of coding work (filters, Stream,
     187  /// Block encoders/decoders etc.). Some special coders use don't use both
     188  /// input and output buffers, but for simplicity they still use this same
     189  /// function prototype.
     190  typedef lzma_ret (*lzma_code_function)(
     191  		void *coder, const lzma_allocator *allocator,
     192  		const uint8_t *restrict in, size_t *restrict in_pos,
     193  		size_t in_size, uint8_t *restrict out,
     194  		size_t *restrict out_pos, size_t out_size,
     195  		lzma_action action);
     196  
     197  /// Type of a function to free the memory allocated for the coder
     198  typedef void (*lzma_end_function)(
     199  		void *coder, const lzma_allocator *allocator);
     200  
     201  
     202  /// Raw coder validates and converts an array of lzma_filter structures to
     203  /// an array of lzma_filter_info structures. This array is used with
     204  /// lzma_next_filter_init to initialize the filter chain.
     205  struct lzma_filter_info_s {
     206  	/// Filter ID. This can be used to share the same initiazation
     207  	/// function *and* data structures with different Filter IDs
     208  	/// (LZMA_FILTER_LZMA1EXT does it), and also by the encoder
     209  	/// with lzma_filters_update() if filter chain is updated
     210  	/// in the middle of a raw stream or Block (LZMA_SYNC_FLUSH).
     211  	lzma_vli id;
     212  
     213  	/// Pointer to function used to initialize the filter.
     214  	/// This is NULL to indicate end of array.
     215  	lzma_init_function init;
     216  
     217  	/// Pointer to filter's options structure
     218  	void *options;
     219  };
     220  
     221  
     222  /// Hold data and function pointers of the next filter in the chain.
     223  struct lzma_next_coder_s {
     224  	/// Pointer to coder-specific data
     225  	void *coder;
     226  
     227  	/// Filter ID. This is LZMA_VLI_UNKNOWN when this structure doesn't
     228  	/// point to a filter coder.
     229  	lzma_vli id;
     230  
     231  	/// "Pointer" to init function. This is never called here.
     232  	/// We need only to detect if we are initializing a coder
     233  	/// that was allocated earlier. See lzma_next_coder_init and
     234  	/// lzma_next_strm_init macros in this file.
     235  	uintptr_t init;
     236  
     237  	/// Pointer to function to do the actual coding
     238  	lzma_code_function code;
     239  
     240  	/// Pointer to function to free lzma_next_coder.coder. This can
     241  	/// be NULL; in that case, lzma_free is called to free
     242  	/// lzma_next_coder.coder.
     243  	lzma_end_function end;
     244  
     245  	/// Pointer to a function to get progress information. If this is NULL,
     246  	/// lzma_stream.total_in and .total_out are used instead.
     247  	void (*get_progress)(void *coder,
     248  			uint64_t *progress_in, uint64_t *progress_out);
     249  
     250  	/// Pointer to function to return the type of the integrity check.
     251  	/// Most coders won't support this.
     252  	lzma_check (*get_check)(const void *coder);
     253  
     254  	/// Pointer to function to get and/or change the memory usage limit.
     255  	/// If new_memlimit == 0, the limit is not changed.
     256  	lzma_ret (*memconfig)(void *coder, uint64_t *memusage,
     257  			uint64_t *old_memlimit, uint64_t new_memlimit);
     258  
     259  	/// Update the filter-specific options or the whole filter chain
     260  	/// in the encoder.
     261  	lzma_ret (*update)(void *coder, const lzma_allocator *allocator,
     262  			const lzma_filter *filters,
     263  			const lzma_filter *reversed_filters);
     264  
     265  	/// Set how many bytes of output this coder may produce at maximum.
     266  	/// On success LZMA_OK must be returned.
     267  	/// If the filter chain as a whole cannot support this feature,
     268  	/// this must return LZMA_OPTIONS_ERROR.
     269  	/// If no input has been given to the coder and the requested limit
     270  	/// is too small, this must return LZMA_BUF_ERROR. If input has been
     271  	/// seen, LZMA_OK is allowed too.
     272  	lzma_ret (*set_out_limit)(void *coder, uint64_t *uncomp_size,
     273  			uint64_t out_limit);
     274  };
     275  
     276  
     277  /// Macro to initialize lzma_next_coder structure
     278  #define LZMA_NEXT_CODER_INIT \
     279  	(lzma_next_coder){ \
     280  		.coder = NULL, \
     281  		.init = (uintptr_t)(NULL), \
     282  		.id = LZMA_VLI_UNKNOWN, \
     283  		.code = NULL, \
     284  		.end = NULL, \
     285  		.get_progress = NULL, \
     286  		.get_check = NULL, \
     287  		.memconfig = NULL, \
     288  		.update = NULL, \
     289  		.set_out_limit = NULL, \
     290  	}
     291  
     292  
     293  /// Internal data for lzma_strm_init, lzma_code, and lzma_end. A pointer to
     294  /// this is stored in lzma_stream.
     295  struct lzma_internal_s {
     296  	/// The actual coder that should do something useful
     297  	lzma_next_coder next;
     298  
     299  	/// Track the state of the coder. This is used to validate arguments
     300  	/// so that the actual coders can rely on e.g. that LZMA_SYNC_FLUSH
     301  	/// is used on every call to lzma_code until next.code has returned
     302  	/// LZMA_STREAM_END.
     303  	enum {
     304  		ISEQ_RUN,
     305  		ISEQ_SYNC_FLUSH,
     306  		ISEQ_FULL_FLUSH,
     307  		ISEQ_FINISH,
     308  		ISEQ_FULL_BARRIER,
     309  		ISEQ_END,
     310  		ISEQ_ERROR,
     311  	} sequence;
     312  
     313  	/// A copy of lzma_stream avail_in. This is used to verify that the
     314  	/// amount of input doesn't change once e.g. LZMA_FINISH has been
     315  	/// used.
     316  	size_t avail_in;
     317  
     318  	/// Indicates which lzma_action values are allowed by next.code.
     319  	bool supported_actions[LZMA_ACTION_MAX + 1];
     320  
     321  	/// If true, lzma_code will return LZMA_BUF_ERROR if no progress was
     322  	/// made (no input consumed and no output produced by next.code).
     323  	bool allow_buf_error;
     324  };
     325  
     326  
     327  /// Allocates memory
     328  lzma_attr_alloc_size(1)
     329  extern void *lzma_alloc(size_t size, const lzma_allocator *allocator);
     330  
     331  /// Allocates memory and zeroes it (like calloc()). This can be faster
     332  /// than lzma_alloc() + memzero() while being backward compatible with
     333  /// custom allocators.
     334  lzma_attr_alloc_size(1)
     335  extern void *lzma_alloc_zero(size_t size, const lzma_allocator *allocator);
     336  
     337  /// Frees memory
     338  extern void lzma_free(void *ptr, const lzma_allocator *allocator);
     339  
     340  
     341  /// Allocates strm->internal if it is NULL, and initializes *strm and
     342  /// strm->internal. This function is only called via lzma_next_strm_init macro.
     343  extern lzma_ret lzma_strm_init(lzma_stream *strm);
     344  
     345  /// Initializes the next filter in the chain, if any. This takes care of
     346  /// freeing the memory of previously initialized filter if it is different
     347  /// than the filter being initialized now. This way the actual filter
     348  /// initialization functions don't need to use lzma_next_coder_init macro.
     349  extern lzma_ret lzma_next_filter_init(lzma_next_coder *next,
     350  		const lzma_allocator *allocator,
     351  		const lzma_filter_info *filters);
     352  
     353  /// Update the next filter in the chain, if any. This checks that
     354  /// the application is not trying to change the Filter IDs.
     355  extern lzma_ret lzma_next_filter_update(
     356  		lzma_next_coder *next, const lzma_allocator *allocator,
     357  		const lzma_filter *reversed_filters);
     358  
     359  /// Frees the memory allocated for next->coder either using next->end or,
     360  /// if next->end is NULL, using lzma_free.
     361  extern void lzma_next_end(lzma_next_coder *next,
     362  		const lzma_allocator *allocator);
     363  
     364  
     365  /// Copy as much data as possible from in[] to out[] and update *in_pos
     366  /// and *out_pos accordingly. Returns the number of bytes copied.
     367  extern size_t lzma_bufcpy(const uint8_t *restrict in, size_t *restrict in_pos,
     368  		size_t in_size, uint8_t *restrict out,
     369  		size_t *restrict out_pos, size_t out_size);
     370  
     371  
     372  /// \brief      Return if expression doesn't evaluate to LZMA_OK
     373  ///
     374  /// There are several situations where we want to return immediately
     375  /// with the value of expr if it isn't LZMA_OK. This macro shortens
     376  /// the code a little.
     377  #define return_if_error(expr) \
     378  do { \
     379  	const lzma_ret ret_ = (expr); \
     380  	if (ret_ != LZMA_OK) \
     381  		return ret_; \
     382  } while (0)
     383  
     384  
     385  /// If next isn't already initialized, free the previous coder. Then mark
     386  /// that next is _possibly_ initialized for the coder using this macro.
     387  /// "Possibly" means that if e.g. allocation of next->coder fails, the
     388  /// structure isn't actually initialized for this coder, but leaving
     389  /// next->init to func is still OK.
     390  #define lzma_next_coder_init(func, next, allocator) \
     391  do { \
     392  	if ((uintptr_t)(func) != (next)->init) \
     393  		lzma_next_end(next, allocator); \
     394  	(next)->init = (uintptr_t)(func); \
     395  } while (0)
     396  
     397  
     398  /// Initializes lzma_strm and calls func() to initialize strm->internal->next.
     399  /// (The function being called will use lzma_next_coder_init()). If
     400  /// initialization fails, memory that wasn't freed by func() is freed
     401  /// along strm->internal.
     402  #define lzma_next_strm_init(func, strm, ...) \
     403  do { \
     404  	return_if_error(lzma_strm_init(strm)); \
     405  	const lzma_ret ret_ = func(&(strm)->internal->next, \
     406  			(strm)->allocator, __VA_ARGS__); \
     407  	if (ret_ != LZMA_OK) { \
     408  		lzma_end(strm); \
     409  		return ret_; \
     410  	} \
     411  } while (0)
     412  
     413  #endif