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 #if defined(_WIN32) || defined(__CYGWIN__)
  21 #       ifdef DLL_EXPORT
  22 #               define LZMA_API_EXPORT __declspec(dllexport)
  23 #       else
  24 #               define LZMA_API_EXPORT
  25 #       endif
  26 // Don't use ifdef or defined() below.
  27 #elif HAVE_VISIBILITY
  28 #       define LZMA_API_EXPORT __attribute__((__visibility__("default")))
  29 #else
  30 #       define LZMA_API_EXPORT
  31 #endif
  32
  33 #define LZMA_API(type) LZMA_API_EXPORT type LZMA_API_CALL
  34
  35 #include "lzma.h"
  36
  37 // These allow helping the compiler in some often-executed branches, whose
  38 // result is almost always the same.
  39 #ifdef __GNUC__
  40 #       define likely(expr) __builtin_expect(expr, true)
  41 #       define unlikely(expr) __builtin_expect(expr, false)
  42 #else
  43 #       define likely(expr) (expr)
  44 #       define unlikely(expr) (expr)
  45 #endif
  46
  47
  48 /// Size of temporary buffers needed in some filters
  49 #define LZMA_BUFFER_SIZE 4096
  50
  51
  52 /// Maximum number of worker threads within one multithreaded component.
  53 /// The limit exists solely to make it simpler to prevent integer overflows
  54 /// when allocating structures etc. This should be big enough for now...
  55 /// the code won't scale anywhere close to this number anyway.
  56 #define LZMA_THREADS_MAX 16384
  57
  58
  59 /// Starting value for memory usage estimates. Instead of calculating size
  60 /// of _every_ structure and taking into account malloc() overhead etc., we
  61 /// add a base size to all memory usage estimates. It's not very accurate
  62 /// but should be easily good enough.
  63 #define LZMA_MEMUSAGE_BASE (UINT64_C(1) << 15)
  64
  65 /// Start of internal Filter ID space. These IDs must never be used
  66 /// in Streams.
  67 #define LZMA_FILTER_RESERVED_START (LZMA_VLI_C(1) << 62)
  68
  69
  70 /// Supported flags that can be passed to lzma_stream_decoder()
  71 /// or lzma_auto_decoder().
  72 #define LZMA_SUPPORTED_FLAGS \
  73         ( LZMA_TELL_NO_CHECK \
  74         | LZMA_TELL_UNSUPPORTED_CHECK \
  75         | LZMA_TELL_ANY_CHECK \
  76         | LZMA_IGNORE_CHECK \
  77         | LZMA_CONCATENATED )
  78
  79
  80 /// Largest valid lzma_action value as unsigned integer.
  81 #define LZMA_ACTION_MAX ((unsigned int)(LZMA_FULL_BARRIER))
  82
  83
  84 /// Special return value (lzma_ret) to indicate that a timeout was reached
  85 /// and lzma_code() must not return LZMA_BUF_ERROR. This is converted to
  86 /// LZMA_OK in lzma_code(). This is not in the lzma_ret enumeration because
  87 /// there's no need to have it in the public API.
  88 #define LZMA_TIMED_OUT 32
  89
  90
  91 typedef struct lzma_next_coder_s lzma_next_coder;
  92
  93 typedef struct lzma_filter_info_s lzma_filter_info;
  94
  95
  96 /// Type of a function used to initialize a filter encoder or decoder
  97 typedef lzma_ret (*lzma_init_function)(
  98                 lzma_next_coder *next, const lzma_allocator *allocator,
  99                 const lzma_filter_info *filters);
 100
 101 /// Type of a function to do some kind of coding work (filters, Stream,
 102 /// Block encoders/decoders etc.). Some special coders use don't use both
 103 /// input and output buffers, but for simplicity they still use this same
 104 /// function prototype.
 105 typedef lzma_ret (*lzma_code_function)(
 106                 void *coder, const lzma_allocator *allocator,
 107                 const uint8_t *restrict in, size_t *restrict in_pos,
 108                 size_t in_size, uint8_t *restrict out,
 109                 size_t *restrict out_pos, size_t out_size,
 110                 lzma_action action);
 111
 112 /// Type of a function to free the memory allocated for the coder
 113 typedef void (*lzma_end_function)(
 114                 void *coder, const lzma_allocator *allocator);
 115
 116
 117 /// Raw coder validates and converts an array of lzma_filter structures to
 118 /// an array of lzma_filter_info structures. This array is used with
 119 /// lzma_next_filter_init to initialize the filter chain.
 120 struct lzma_filter_info_s {
 121         /// Filter ID. This is used only by the encoder
 122         /// with lzma_filters_update().
 123         lzma_vli id;
 124
 125         /// Pointer to function used to initialize the filter.
 126         /// This is NULL to indicate end of array.
 127         lzma_init_function init;
 128
 129         /// Pointer to filter's options structure
 130         void *options;
 131 };
 132
 133
 134 /// Hold data and function pointers of the next filter in the chain.
 135 struct lzma_next_coder_s {
 136         /// Pointer to coder-specific data
 137         void *coder;
 138
 139         /// Filter ID. This is LZMA_VLI_UNKNOWN when this structure doesn't
 140         /// point to a filter coder.
 141         lzma_vli id;
 142
 143         /// "Pointer" to init function. This is never called here.
 144         /// We need only to detect if we are initializing a coder
 145         /// that was allocated earlier. See lzma_next_coder_init and
 146         /// lzma_next_strm_init macros in this file.
 147         uintptr_t init;
 148
 149         /// Pointer to function to do the actual coding
 150         lzma_code_function code;
 151
 152         /// Pointer to function to free lzma_next_coder.coder. This can
 153         /// be NULL; in that case, lzma_free is called to free
 154         /// lzma_next_coder.coder.
 155         lzma_end_function end;
 156
 157         /// Pointer to a function to get progress information. If this is NULL,
 158         /// lzma_stream.total_in and .total_out are used instead.
 159         void (*get_progress)(void *coder,
 160                         uint64_t *progress_in, uint64_t *progress_out);
 161
 162         /// Pointer to function to return the type of the integrity check.
 163         /// Most coders won't support this.
 164         lzma_check (*get_check)(const void *coder);
 165
 166         /// Pointer to function to get and/or change the memory usage limit.
 167         /// If new_memlimit == 0, the limit is not changed.
 168         lzma_ret (*memconfig)(void *coder, uint64_t *memusage,
 169                         uint64_t *old_memlimit, uint64_t new_memlimit);
 170
 171         /// Update the filter-specific options or the whole filter chain
 172         /// in the encoder.
 173         lzma_ret (*update)(void *coder, const lzma_allocator *allocator,
 174                         const lzma_filter *filters,
 175                         const lzma_filter *reversed_filters);
 176 };
 177
 178
 179 /// Macro to initialize lzma_next_coder structure
 180 #define LZMA_NEXT_CODER_INIT \
 181         (lzma_next_coder){ \
 182                 .coder = NULL, \
 183                 .init = (uintptr_t)(NULL), \
 184                 .id = LZMA_VLI_UNKNOWN, \
 185                 .code = NULL, \
 186                 .end = NULL, \
 187                 .get_progress = NULL, \
 188                 .get_check = NULL, \
 189                 .memconfig = NULL, \
 190                 .update = NULL, \
 191         }
 192
 193
 194 /// Internal data for lzma_strm_init, lzma_code, and lzma_end. A pointer to
 195 /// this is stored in lzma_stream.
 196 struct lzma_internal_s {
 197         /// The actual coder that should do something useful
 198         lzma_next_coder next;
 199
 200         /// Track the state of the coder. This is used to validate arguments
 201         /// so that the actual coders can rely on e.g. that LZMA_SYNC_FLUSH
 202         /// is used on every call to lzma_code until next.code has returned
 203         /// LZMA_STREAM_END.
 204         enum {
 205                 ISEQ_RUN,
 206                 ISEQ_SYNC_FLUSH,
 207                 ISEQ_FULL_FLUSH,
 208                 ISEQ_FINISH,
 209                 ISEQ_FULL_BARRIER,
 210                 ISEQ_END,
 211                 ISEQ_ERROR,
 212         } sequence;
 213
 214         /// A copy of lzma_stream avail_in. This is used to verify that the
 215         /// amount of input doesn't change once e.g. LZMA_FINISH has been
 216         /// used.
 217         size_t avail_in;
 218
 219         /// Indicates which lzma_action values are allowed by next.code.
 220         bool supported_actions[LZMA_ACTION_MAX + 1];
 221
 222         /// If true, lzma_code will return LZMA_BUF_ERROR if no progress was
 223         /// made (no input consumed and no output produced by next.code).
 224         bool allow_buf_error;
 225 };
 226
 227
 228 /// Allocates memory
 229 extern void *lzma_alloc(size_t size, const lzma_allocator *allocator)
 230                 lzma_attribute((__malloc__)) lzma_attr_alloc_size(1);
 231
 232 /// Allocates memory and zeroes it (like calloc()). This can be faster
 233 /// than lzma_alloc() + memzero() while being backward compatible with
 234 /// custom allocators.
 235 extern void * lzma_attribute((__malloc__)) lzma_attr_alloc_size(1)
 236                 lzma_alloc_zero(size_t size, const lzma_allocator *allocator);
 237
 238 /// Frees memory
 239 extern void lzma_free(void *ptr, const lzma_allocator *allocator);
 240
 241
 242 /// Allocates strm->internal if it is NULL, and initializes *strm and
 243 /// strm->internal. This function is only called via lzma_next_strm_init macro.
 244 extern lzma_ret lzma_strm_init(lzma_stream *strm);
 245
 246 /// Initializes the next filter in the chain, if any. This takes care of
 247 /// freeing the memory of previously initialized filter if it is different
 248 /// than the filter being initialized now. This way the actual filter
 249 /// initialization functions don't need to use lzma_next_coder_init macro.
 250 extern lzma_ret lzma_next_filter_init(lzma_next_coder *next,
 251                 const lzma_allocator *allocator,
 252                 const lzma_filter_info *filters);
 253
 254 /// Update the next filter in the chain, if any. This checks that
 255 /// the application is not trying to change the Filter IDs.
 256 extern lzma_ret lzma_next_filter_update(
 257                 lzma_next_coder *next, const lzma_allocator *allocator,
 258                 const lzma_filter *reversed_filters);
 259
 260 /// Frees the memory allocated for next->coder either using next->end or,
 261 /// if next->end is NULL, using lzma_free.
 262 extern void lzma_next_end(lzma_next_coder *next,
 263                 const lzma_allocator *allocator);
 264
 265
 266 /// Copy as much data as possible from in[] to out[] and update *in_pos
 267 /// and *out_pos accordingly. Returns the number of bytes copied.
 268 extern size_t lzma_bufcpy(const uint8_t *restrict in, size_t *restrict in_pos,
 269                 size_t in_size, uint8_t *restrict out,
 270                 size_t *restrict out_pos, size_t out_size);
 271
 272
 273 /// \brief      Return if expression doesn't evaluate to LZMA_OK
 274 ///
 275 /// There are several situations where we want to return immediately
 276 /// with the value of expr if it isn't LZMA_OK. This macro shortens
 277 /// the code a little.
 278 #define return_if_error(expr) \
 279 do { \
 280         const lzma_ret ret_ = (expr); \
 281         if (ret_ != LZMA_OK) \
 282                 return ret_; \
 283 } while (0)
 284
 285
 286 /// If next isn't already initialized, free the previous coder. Then mark
 287 /// that next is _possibly_ initialized for the coder using this macro.
 288 /// "Possibly" means that if e.g. allocation of next->coder fails, the
 289 /// structure isn't actually initialized for this coder, but leaving
 290 /// next->init to func is still OK.
 291 #define lzma_next_coder_init(func, next, allocator) \
 292 do { \
 293         if ((uintptr_t)(func) != (next)->init) \
 294                 lzma_next_end(next, allocator); \
 295         (next)->init = (uintptr_t)(func); \
 296 } while (0)
 297
 298
 299 /// Initializes lzma_strm and calls func() to initialize strm->internal->next.
 300 /// (The function being called will use lzma_next_coder_init()). If
 301 /// initialization fails, memory that wasn't freed by func() is freed
 302 /// along strm->internal.
 303 #define lzma_next_strm_init(func, strm, ...) \
 304 do { \
 305         return_if_error(lzma_strm_init(strm)); \
 306         const lzma_ret ret_ = func(&(strm)->internal->next, \
 307                         (strm)->allocator, __VA_ARGS__); \
 308         if (ret_ != LZMA_OK) { \
 309                 lzma_end(strm); \
 310                 return ret_; \
 311         } \
 312 } while (0)
 313
 314 #endif