include/vlc_common.h

   1 /*****************************************************************************
   2  * vlc_common.h: common definitions
   3  * Collection of useful common types and macros definitions
   4  *****************************************************************************
   5  * Copyright (C) 1998-2011 VLC authors and VideoLAN
   6  *
   7  * Authors: Samuel Hocevar <sam@via.ecp.fr>
   8  *          Vincent Seguin <seguin@via.ecp.fr>
   9  *          Gildas Bazin <gbazin@videolan.org>
  10  *          Rémi Denis-Courmont
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU Lesser General Public License as published by
  14  * the Free Software Foundation; either version 2.1 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU Lesser General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public License
  23  * along with this program; if not, write to the Free Software Foundation,
  24  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 #ifndef VLC_COMMON_H
  28 # define VLC_COMMON_H 1
  29
  30 /**
  31  * \defgroup vlc VLC plug-in programming interface
  32  * \file
  33  * \ingroup vlc
  34  * This file is a collection of common definitions and types
  35  */
  36
  37 /*****************************************************************************
  38  * Required vlc headers
  39  *****************************************************************************/
  40 #include "vlc_config.h"
  41
  42 /*****************************************************************************
  43  * Required system headers
  44  *****************************************************************************/
  45 #include <stdlib.h>
  46 #include <stdarg.h>
  47
  48 #include <string.h>
  49 #include <stdio.h>
  50 #include <inttypes.h>
  51 #include <stddef.h>
  52
  53 #ifndef __cplusplus
  54 # include <stdbool.h>
  55 #endif
  56
  57 /**
  58  * \defgroup cext C programming language extensions
  59  * \ingroup vlc
  60  *
  61  * This section defines a number of macros and inline functions extending the
  62  * C language. Most extensions are implemented by GCC and LLVM/Clang, and have
  63  * unoptimized fallbacks for other C11/C++11 conforming compilers.
  64  * @{
  65  */
  66 #ifdef __GNUC__
  67 # define VLC_GCC_VERSION(maj,min) \
  68     ((__GNUC__ > (maj)) || (__GNUC__ == (maj) && __GNUC_MINOR__ >= (min)))
  69 #else
  70 /** GCC version check */
  71 # define VLC_GCC_VERSION(maj,min) (0)
  72 #endif
  73
  74 /* Try to fix format strings for all versions of mingw and mingw64 */
  75 #if defined( _WIN32 ) && defined( __USE_MINGW_ANSI_STDIO )
  76  #undef PRId64
  77  #define PRId64 "lld"
  78  #undef PRIi64
  79  #define PRIi64 "lli"
  80  #undef PRIu64
  81  #define PRIu64 "llu"
  82  #undef PRIo64
  83  #define PRIo64 "llo"
  84  #undef PRIx64
  85  #define PRIx64 "llx"
  86  #define snprintf __mingw_snprintf
  87  #define vsnprintf __mingw_vsnprintf
  88  #define swprintf _snwprintf
  89 #endif
  90
  91 /* Function attributes for compiler warnings */
  92 #ifdef __GNUC__
  93 # define VLC_DEPRECATED __attribute__((deprecated))
  94 # if VLC_GCC_VERSION(6,0)
  95 #  define VLC_DEPRECATED_ENUM __attribute__((deprecated))
  96 # else
  97 #  define VLC_DEPRECATED_ENUM
  98 # endif
  99
 100 # if defined( _WIN32 ) && !defined( __clang__ )
 101 #  define VLC_FORMAT(x,y) __attribute__ ((format(gnu_printf,x,y)))
 102 # else
 103 #  define VLC_FORMAT(x,y) __attribute__ ((format(printf,x,y)))
 104 # endif
 105 # define VLC_FORMAT_ARG(x) __attribute__ ((format_arg(x)))
 106 # define VLC_MALLOC __attribute__ ((malloc))
 107 # define VLC_USED __attribute__ ((warn_unused_result))
 108
 109 #else
 110 /**
 111  * Deprecated functions or compound members annotation
 112  *
 113  * Use this macro in front of a function declaration or compound member
 114  * within a compound type declaration.
 115  * The compiler may emit a warning every time the function or member is used.
 116  *
 117  * Use \ref VLC_DEPRECATED_ENUM instead for enumeration members.
 118  */
 119 # define VLC_DEPRECATED
 120
 121 /**
 122  * Deprecated enum member annotation
 123  *
 124  * Use this macro after an enumerated type member declaration.
 125  * The compiler may emit a warning every time the enumeration member is used.
 126  *
 127  * See also \ref VLC_DEPRECATED.
 128  */
 129 # define VLC_DEPRECATED_ENUM
 130
 131 /**
 132  * String format function annotation
 133  *
 134  * Use this macro after a function prototype/declaration if the function
 135  * expects a standard C format string. This helps compiler diagnostics.
 136  *
 137  * @param x the position (starting from 1) of the format string argument
 138  * @param y the first position (also starting from 1) of the variable arguments
 139  *          following the format string (usually but not always \p x+1).
 140  */
 141 # define VLC_FORMAT(x,y)
 142
 143 /**
 144  * Format string translation function annotation
 145  *
 146  * Use this macro after a function prototype/declaration if the function
 147  * expects a format string as input and returns another format string as output
 148  * to another function.
 149  *
 150  * This is primarily intended for localization functions such as gettext().
 151  */
 152 # define VLC_FORMAT_ARG(x)
 153
 154 /**
 155  * Heap allocated result function annotation
 156  *
 157  * Use this macro to annotate a function that returns a pointer to memory that
 158  * cannot alias any other valid pointer.
 159  *
 160  * This is primarily used for functions that return a pointer to heap-allocated
 161  * memory, but it can be used for other applicable purposes.
 162  *
 163  * \warning Do not use this annotation if the returned pointer can in any way
 164  * alias a valid pointer at the time the function exits. This could lead to
 165  * very weird memory corruption bugs.
 166  */
 167 # define VLC_MALLOC
 168
 169 /**
 170  * Used result function annotation
 171  *
 172  * Use this macro to annotate a function whose result must be used.
 173  *
 174  * There are several cases where this is useful:
 175  * - If a function has no side effects (or no useful side effects), such that
 176  *   the only useful purpose of calling said function is to obtain its
 177  *   return value.
 178  * - If ignoring the function return value would lead to a resource leak
 179  *   (including but not limited to a memory leak).
 180  * - If a function cannot be used correctly without checking its return value.
 181  *   For instance, if the function can fail at any time.
 182  *
 183  * The compiler may warn if the return value of a function call is ignored.
 184  */
 185 # define VLC_USED
 186 #endif
 187
 188 #if defined (__ELF__) || defined (__MACH__)
 189 # define VLC_WEAK __attribute__((weak))
 190 #else
 191 /**
 192  * Weak symbol annotation
 193  *
 194  * Use this macro before an external identifier \b definition to mark it as a
 195  * weak symbol. A weak symbol can be overriden by another symbol of the same
 196  * name at the link time.
 197  */
 198 # define VLC_WEAK
 199 #endif
 200
 201 /* Branch prediction */
 202 #if defined (__GNUC__) || defined (__clang__)
 203 # define likely(p)     __builtin_expect(!!(p), 1)
 204 # define unlikely(p)   __builtin_expect(!!(p), 0)
 205 # define unreachable() __builtin_unreachable()
 206 #else
 207 /**
 208  * Predicted true condition
 209  *
 210  * This macro indicates that the condition is expected most often true.
 211  * The compiler may optimize the code assuming that this condition is usually
 212  * met.
 213  */
 214 # define likely(p)     (!!(p))
 215
 216 /**
 217  * Predicted false condition
 218  *
 219  * This macro indicates that the condition is expected most often false.
 220  * The compiler may optimize the code assuming that this condition is rarely
 221  * met.
 222  */
 223 # define unlikely(p)   (!!(p))
 224
 225 /**
 226  * Impossible branch
 227  *
 228  * This macro indicates that the branch cannot be reached at run-time, and
 229  * represents undefined behaviour.
 230  * The compiler may optimize the code assuming that the call flow will never
 231  * logically reach the point where this macro is expanded.
 232  *
 233  * See also \ref vlc_assert_unreachable.
 234  */
 235 # define unreachable() ((void)0)
 236 #endif
 237
 238 /**
 239  * Impossible branch assertion
 240  *
 241  * This macro asserts that the branch cannot be reached at run-time.
 242  *
 243  * If the branch is reached in a debug build, it will trigger an assertion
 244  * failure and abnormal program termination.
 245  *
 246  * If the branch is reached in a non-debug build, this macro is equivalent to
 247  * \ref unreachable and the behaviour is undefined.
 248  */
 249 #define vlc_assert_unreachable() (vlc_assert(!"unreachable"), unreachable())
 250
 251 /**
 252  * Run-time assertion
 253  *
 254  * This macro performs a run-time assertion if C assertions are enabled
 255  * and the following preprocessor symbol is defined:
 256  * @verbatim __LIBVLC__ @endverbatim
 257  * That restriction ensures that assertions in public header files are not
 258  * unwittingly <i>leaked</i> to externally-compiled plug-ins
 259  * including those header files.
 260  *
 261  * Within the LibVLC code base, this is exactly the same as assert(), which can
 262  * and probably should be used directly instead.
 263  */
 264 #ifdef __LIBVLC__
 265 # define vlc_assert(pred) assert(pred)
 266 #else
 267 # define vlc_assert(pred) ((void)0)
 268 #endif
 269
 270 /* Linkage */
 271 #ifdef __cplusplus
 272 # define VLC_EXTERN extern "C"
 273 #else
 274 # define VLC_EXTERN
 275 #endif
 276
 277 #if defined (_WIN32) && defined (DLL_EXPORT)
 278 # define VLC_EXPORT __declspec(dllexport)
 279 #elif defined (__GNUC__)
 280 # define VLC_EXPORT __attribute__((visibility("default")))
 281 #else
 282 # define VLC_EXPORT
 283 #endif
 284
 285 /**
 286  * Exported API call annotation
 287  *
 288  * This macro is placed before a function declaration to indicate that the
 289  * function is an API call of the LibVLC plugin API.
 290  */
 291 #define VLC_API VLC_EXTERN VLC_EXPORT
 292
 293 /** @} */
 294
 295 /*****************************************************************************
 296  * Basic types definitions
 297  *****************************************************************************/
 298 /**
 299  * The vlc_fourcc_t type.
 300  *
 301  * See http://www.webartz.com/fourcc/ for a very detailed list.
 302  */
 303 typedef uint32_t vlc_fourcc_t;
 304
 305 #ifdef WORDS_BIGENDIAN
 306 #   define VLC_FOURCC( a, b, c, d ) \
 307         ( ((uint32_t)d) | ( ((uint32_t)c) << 8 ) \
 308            | ( ((uint32_t)b) << 16 ) | ( ((uint32_t)a) << 24 ) )
 309 #   define VLC_TWOCC( a, b ) \
 310         ( (uint16_t)(b) | ( (uint16_t)(a) << 8 ) )
 311
 312 #else
 313 #   define VLC_FOURCC( a, b, c, d ) \
 314         ( ((uint32_t)a) | ( ((uint32_t)b) << 8 ) \
 315            | ( ((uint32_t)c) << 16 ) | ( ((uint32_t)d) << 24 ) )
 316 #   define VLC_TWOCC( a, b ) \
 317         ( (uint16_t)(a) | ( (uint16_t)(b) << 8 ) )
 318
 319 #endif
 320
 321 /**
 322  * Translate a vlc_fourcc into its string representation. This function
 323  * assumes there is enough room in psz_fourcc to store 4 characters in.
 324  *
 325  * \param fcc a vlc_fourcc_t
 326  * \param psz_fourcc string to store string representation of vlc_fourcc in
 327  */
 328 static inline void vlc_fourcc_to_char( vlc_fourcc_t fcc, char *psz_fourcc )
 329 {
 330     memcpy( psz_fourcc, &fcc, 4 );
 331 }
 332
 333 /*****************************************************************************
 334  * Classes declaration
 335  *****************************************************************************/
 336
 337 /* Internal types */
 338 typedef struct vlc_object_t vlc_object_t;
 339 typedef struct libvlc_int_t libvlc_int_t;
 340 typedef struct date_t date_t;
 341
 342 /* Playlist */
 343
 344 typedef struct playlist_t playlist_t;
 345 typedef struct playlist_item_t playlist_item_t;
 346 typedef struct services_discovery_t services_discovery_t;
 347 typedef struct vlc_renderer_discovery_t vlc_renderer_discovery_t;
 348 typedef struct vlc_renderer_item_t vlc_renderer_item_t;
 349
 350 /* Modules */
 351 typedef struct module_t module_t;
 352 typedef struct module_config_t module_config_t;
 353
 354 typedef struct config_category_t config_category_t;
 355
 356 /* Input */
 357 typedef struct input_item_t input_item_t;
 358 typedef struct input_item_node_t input_item_node_t;
 359 typedef struct input_source_t input_source_t;
 360 typedef struct stream_t     stream_t;
 361 typedef struct stream_t demux_t;
 362 typedef struct es_out_t     es_out_t;
 363 typedef struct es_out_id_t  es_out_id_t;
 364 typedef struct seekpoint_t seekpoint_t;
 365 typedef struct info_t info_t;
 366 typedef struct info_category_t info_category_t;
 367 typedef struct input_attachment_t input_attachment_t;
 368
 369 /* Format */
 370 typedef struct audio_format_t audio_format_t;
 371 typedef struct video_format_t video_format_t;
 372 typedef struct subs_format_t subs_format_t;
 373 typedef struct es_format_t es_format_t;
 374 typedef struct video_palette_t video_palette_t;
 375 typedef struct vlc_es_id_t vlc_es_id_t;
 376
 377 /* Audio */
 378 typedef struct audio_output audio_output_t;
 379 typedef audio_format_t audio_sample_format_t;
 380
 381 /* Video */
 382 typedef struct vout_thread_t vout_thread_t;
 383 typedef struct vlc_viewpoint_t vlc_viewpoint_t;
 384
 385 typedef video_format_t video_frame_format_t;
 386 typedef struct picture_t picture_t;
 387
 388 /* Subpictures */
 389 typedef struct spu_t spu_t;
 390 typedef struct subpicture_t subpicture_t;
 391 typedef struct subpicture_region_t subpicture_region_t;
 392
 393 typedef struct image_handler_t image_handler_t;
 394
 395 /* Stream output */
 396 typedef struct sout_instance_t sout_instance_t;
 397
 398 typedef struct sout_input_t sout_input_t;
 399 typedef struct sout_packetizer_input_t sout_packetizer_input_t;
 400
 401 typedef struct sout_access_out_t sout_access_out_t;
 402
 403 typedef struct sout_mux_t sout_mux_t;
 404
 405 typedef struct sout_stream_t    sout_stream_t;
 406
 407 typedef struct config_chain_t       config_chain_t;
 408 typedef struct session_descriptor_t session_descriptor_t;
 409
 410 /* Decoders */
 411 typedef struct decoder_t         decoder_t;
 412
 413 /* Encoders */
 414 typedef struct encoder_t      encoder_t;
 415
 416 /* Filters */
 417 typedef struct filter_t filter_t;
 418
 419 /* Network */
 420 typedef struct vlc_url_t vlc_url_t;
 421
 422 /* Misc */
 423 typedef struct iso639_lang_t iso639_lang_t;
 424
 425 /* block */
 426 typedef struct block_t      block_t;
 427 typedef struct block_fifo_t block_fifo_t;
 428
 429 /* Hashing */
 430 typedef struct vlc_hash_md5_ctx vlc_hash_md5_t;
 431
 432 /* XML */
 433 typedef struct xml_t xml_t;
 434 typedef struct xml_reader_t xml_reader_t;
 435
 436 /* vod server */
 437 typedef struct vod_t     vod_t;
 438 typedef struct vod_media_t vod_media_t;
 439
 440 /* VLM */
 441 typedef struct vlm_t         vlm_t;
 442 typedef struct vlm_message_t vlm_message_t;
 443
 444 /* misc */
 445 typedef struct vlc_meta_t    vlc_meta_t;
 446 typedef struct input_stats_t input_stats_t;
 447 typedef struct addon_entry_t addon_entry_t;
 448
 449 /* Update */
 450 typedef struct update_t update_t;
 451
 452 /**
 453  * VLC value structure
 454  */
 455 typedef union
 456 {
 457     int64_t         i_int;
 458     bool            b_bool;
 459     float           f_float;
 460     char *          psz_string;
 461     void *          p_address;
 462     struct { int32_t x; int32_t y; } coords;
 463
 464 } vlc_value_t;
 465
 466 /*****************************************************************************
 467  * Error values (shouldn't be exposed)
 468  *****************************************************************************/
 469 /** No error */
 470 #define VLC_SUCCESS        (-0)
 471 /** Unspecified error */
 472 #define VLC_EGENERIC       (-1)
 473 /** Not enough memory */
 474 #define VLC_ENOMEM         (-2)
 475 /** Timeout */
 476 #define VLC_ETIMEOUT       (-3)
 477 /** Module not found */
 478 #define VLC_ENOMOD         (-4)
 479 /** Object not found */
 480 #define VLC_ENOOBJ         (-5)
 481 /** Variable not found */
 482 #define VLC_ENOVAR         (-6)
 483 /** Bad variable value */
 484 #define VLC_EBADVAR        (-7)
 485 /** Item not found */
 486 #define VLC_ENOITEM        (-8)
 487
 488 /*****************************************************************************
 489  * Variable callbacks: called when the value is modified
 490  *****************************************************************************/
 491 typedef int ( * vlc_callback_t ) ( vlc_object_t *,      /* variable's object */
 492                                    char const *,            /* variable name */
 493                                    vlc_value_t,                 /* old value */
 494                                    vlc_value_t,                 /* new value */
 495                                    void * );                /* callback data */
 496
 497 /*****************************************************************************
 498  * List callbacks: called when elements are added/removed from the list
 499  *****************************************************************************/
 500 typedef int ( * vlc_list_callback_t ) ( vlc_object_t *,      /* variable's object */
 501                                         char const *,            /* variable name */
 502                                         int,                  /* VLC_VAR_* action */
 503                                         vlc_value_t *,      /* new/deleted value  */
 504                                         void *);                 /* callback data */
 505
 506 /*****************************************************************************
 507  * OS-specific headers and thread types
 508  *****************************************************************************/
 509 #if defined( _WIN32 )
 510 #   include <malloc.h>
 511 #   ifndef PATH_MAX
 512 #       define PATH_MAX MAX_PATH
 513 #   endif
 514 #   include <windows.h>
 515 #endif
 516
 517 #ifdef __APPLE__
 518 #include <sys/syslimits.h>
 519 #include <AvailabilityMacros.h>
 520 #endif
 521
 522 #ifdef __OS2__
 523 #   define OS2EMX_PLAIN_CHAR
 524 #   define INCL_BASE
 525 #   define INCL_PM
 526 #   include <os2safe.h>
 527 #   include <os2.h>
 528 #endif
 529
 530 #include "vlc_tick.h"
 531 #include "vlc_threads.h"
 532
 533 /**
 534  * \defgroup intops Integer operations
 535  * \ingroup cext
 536  *
 537  * Common integer functions.
 538  * @{
 539  */
 540 /* __MAX and __MIN: self explanatory */
 541 #ifndef __MAX
 542 #   define __MAX(a, b)   ( ((a) > (b)) ? (a) : (b) )
 543 #endif
 544 #ifndef __MIN
 545 #   define __MIN(a, b)   ( ((a) < (b)) ? (a) : (b) )
 546 #endif
 547
 548 /* clip v in [min, max] */
 549 #define VLC_CLIP(v, min, max)    __MIN(__MAX((v), (min)), (max))
 550
 551 /**
 552  * Make integer v a multiple of align
 553  *
 554  * \note align must be a power of 2
 555  */
 556 VLC_USED
 557 static inline size_t vlc_align(size_t v, size_t align)
 558 {
 559     return (v + (align - 1)) & ~(align - 1);
 560 }
 561
 562 #if defined(__clang__) && __has_attribute(diagnose_if)
 563 static inline size_t vlc_align(size_t v, size_t align)
 564     __attribute__((diagnose_if(((align & (align - 1)) || (align == 0)),
 565         "align must be power of 2", "error")));
 566 #endif
 567
 568 /** Greatest common divisor */
 569 VLC_USED
 570 static inline int64_t GCD ( int64_t a, int64_t b )
 571 {
 572     while( b )
 573     {
 574         int64_t c = a % b;
 575         a = b;
 576         b = c;
 577     }
 578     return a;
 579 }
 580
 581 /* function imported from libavutil/common.h */
 582 VLC_USED
 583 static inline uint8_t clip_uint8_vlc( int32_t a )
 584 {
 585     if( a&(~255) ) return (-a)>>31;
 586     else           return a;
 587 }
 588
 589 /**
 590  * \defgroup bitops Bit operations
 591  * @{
 592  */
 593
 594 #define VLC_INT_FUNC(basename) \
 595         VLC_INT_FUNC_TYPE(basename, unsigned, ) \
 596         VLC_INT_FUNC_TYPE(basename, unsigned long, l) \
 597         VLC_INT_FUNC_TYPE(basename, unsigned long long, ll)
 598
 599 #if defined (__GNUC__) || defined (__clang__)
 600 # define VLC_INT_FUNC_TYPE(basename,type,suffix) \
 601 VLC_USED static inline int vlc_##basename##suffix(type x) \
 602 { \
 603     return __builtin_##basename##suffix(x); \
 604 }
 605
 606 VLC_INT_FUNC(clz)
 607 #else
 608 VLC_USED static inline int vlc_clzll(unsigned long long x)
 609 {
 610     int i = sizeof (x) * 8;
 611
 612     while (x)
 613     {
 614         x >>= 1;
 615         i--;
 616     }
 617     return i;
 618 }
 619
 620 VLC_USED static inline int vlc_clzl(unsigned long x)
 621 {
 622     return vlc_clzll(x) - ((sizeof (long long) - sizeof (long)) * 8);
 623 }
 624
 625 VLC_USED static inline int vlc_clz(unsigned x)
 626 {
 627     return vlc_clzll(x) - ((sizeof (long long) - sizeof (int)) * 8);
 628 }
 629
 630 VLC_USED static inline int vlc_ctz_generic(unsigned long long x)
 631 {
 632     unsigned i = sizeof (x) * 8;
 633
 634     while (x)
 635     {
 636         x <<= 1;
 637         i--;
 638     }
 639     return i;
 640 }
 641
 642 VLC_USED static inline int vlc_parity_generic(unsigned long long x)
 643 {
 644     for (unsigned i = 4 * sizeof (x); i > 0; i /= 2)
 645         x ^= x >> i;
 646     return x & 1;
 647 }
 648
 649 VLC_USED static inline int vlc_popcount_generic(unsigned long long x)
 650 {
 651     int count = 0;
 652     while (x)
 653     {
 654         count += x & 1;
 655         x = x >> 1;
 656     }
 657     return count;
 658 }
 659
 660 # define VLC_INT_FUNC_TYPE(basename,type,suffix) \
 661 VLC_USED static inline int vlc_##basename##suffix(type x) \
 662 { \
 663     return vlc_##basename##_generic(x); \
 664 }
 665 #endif
 666
 667 VLC_INT_FUNC(ctz)
 668 VLC_INT_FUNC(parity)
 669 VLC_INT_FUNC(popcount)
 670
 671 #ifndef __cplusplus
 672 # define VLC_INT_GENERIC(func,x) \
 673     _Generic((x), \
 674         unsigned char:      func(x), \
 675           signed char:      func(x), \
 676         unsigned short:     func(x), \
 677           signed short:     func(x), \
 678         unsigned int:       func(x), \
 679           signed int:       func(x), \
 680         unsigned long:      func##l(x), \
 681           signed long:      func##l(x), \
 682         unsigned long long: func##ll(x), \
 683           signed long long: func##ll(x))
 684
 685 /**
 686  * Count leading zeroes
 687  *
 688  * This function counts the number of consecutive zero (clear) bits
 689  * down from the highest order bit in an unsigned integer.
 690  *
 691  * \param x a non-zero integer
 692  * \note This macro assumes that CHAR_BIT equals 8.
 693  * \warning By definition, the result depends on the (width of the) type of x.
 694  * \return The number of leading zero bits in x.
 695  */
 696 # define clz(x) \
 697     _Generic((x), \
 698         unsigned char: (vlc_clz(x) - (sizeof (unsigned) - 1) * 8), \
 699         unsigned short: (vlc_clz(x) \
 700         - (sizeof (unsigned) - sizeof (unsigned short)) * 8), \
 701         unsigned: vlc_clz(x), \
 702         unsigned long: vlc_clzl(x), \
 703         unsigned long long: vlc_clzll(x))
 704
 705 /**
 706  * Count trailing zeroes
 707  *
 708  * This function counts the number of consecutive zero bits
 709  * up from the lowest order bit in an unsigned integer.
 710  *
 711  * \param x a non-zero integer
 712  * \note This function assumes that CHAR_BIT equals 8.
 713  * \return The number of trailing zero bits in x.
 714  */
 715 # define ctz(x) VLC_INT_GENERIC(vlc_ctz, x)
 716
 717 /**
 718  * Parity
 719  *
 720  * This function determines the parity of an integer.
 721  * \retval 0 if x has an even number of set bits.
 722  * \retval 1 if x has an odd number of set bits.
 723  */
 724 # define parity(x) VLC_INT_GENERIC(vlc_parity, x)
 725
 726 /**
 727  * Bit weight / population count
 728  *
 729  * This function counts the number of non-zero bits in an integer.
 730  *
 731  * \return The count of non-zero bits.
 732  */
 733 # define vlc_popcount(x) \
 734     _Generic((x), \
 735         signed char:  vlc_popcount((unsigned char)(x)), \
 736         signed short: vlc_popcount((unsigned short)(x)), \
 737         default: VLC_INT_GENERIC(vlc_popcount ,x))
 738 #else
 739 VLC_USED static inline int vlc_popcount(unsigned char x)
 740 {
 741     return vlc_popcount((unsigned)x);
 742 }
 743
 744 VLC_USED static inline int vlc_popcount(unsigned short x)
 745 {
 746     return vlc_popcount((unsigned)x);
 747 }
 748
 749 VLC_USED static inline int vlc_popcount(unsigned long x)
 750 {
 751     return vlc_popcountl(x);
 752 }
 753
 754 VLC_USED static inline int vlc_popcount(unsigned long long x)
 755 {
 756     return vlc_popcountll(x);
 757 }
 758 #endif
 759
 760 /** Byte swap (16 bits) */
 761 VLC_USED
 762 static inline uint16_t vlc_bswap16(uint16_t x)
 763 {
 764     return (x << 8) | (x >> 8);
 765 }
 766
 767 /** Byte swap (32 bits) */
 768 VLC_USED
 769 static inline uint32_t vlc_bswap32(uint32_t x)
 770 {
 771 #if defined (__GNUC__) || defined(__clang__)
 772     return __builtin_bswap32 (x);
 773 #else
 774     return ((x & 0x000000FF) << 24)
 775          | ((x & 0x0000FF00) <<  8)
 776          | ((x & 0x00FF0000) >>  8)
 777          | ((x & 0xFF000000) >> 24);
 778 #endif
 779 }
 780
 781 /** Byte swap (64 bits) */
 782 VLC_USED
 783 static inline uint64_t vlc_bswap64(uint64_t x)
 784 {
 785 #if defined (__GNUC__) || defined(__clang__)
 786     return __builtin_bswap64 (x);
 787 #elif !defined (__cplusplus)
 788     return ((x & 0x00000000000000FF) << 56)
 789          | ((x & 0x000000000000FF00) << 40)
 790          | ((x & 0x0000000000FF0000) << 24)
 791          | ((x & 0x00000000FF000000) <<  8)
 792          | ((x & 0x000000FF00000000) >>  8)
 793          | ((x & 0x0000FF0000000000) >> 24)
 794          | ((x & 0x00FF000000000000) >> 40)
 795          | ((x & 0xFF00000000000000) >> 56);
 796 #else
 797     return ((x & 0x00000000000000FFULL) << 56)
 798          | ((x & 0x000000000000FF00ULL) << 40)
 799          | ((x & 0x0000000000FF0000ULL) << 24)
 800          | ((x & 0x00000000FF000000ULL) <<  8)
 801          | ((x & 0x000000FF00000000ULL) >>  8)
 802          | ((x & 0x0000FF0000000000ULL) >> 24)
 803          | ((x & 0x00FF000000000000ULL) >> 40)
 804          | ((x & 0xFF00000000000000ULL) >> 56);
 805 #endif
 806 }
 807 /** @} */
 808
 809 /**
 810  * \defgroup overflow Overflowing arithmetic
 811  * @{
 812  */
 813 static inline bool uadd_overflow(unsigned a, unsigned b, unsigned *res)
 814 {
 815 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 816      return __builtin_uadd_overflow(a, b, res);
 817 #else
 818      *res = a + b;
 819      return (a + b) < a;
 820 #endif
 821 }
 822
 823 static inline bool uaddl_overflow(unsigned long a, unsigned long b,
 824                                   unsigned long *res)
 825 {
 826 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 827      return __builtin_uaddl_overflow(a, b, res);
 828 #else
 829      *res = a + b;
 830      return (a + b) < a;
 831 #endif
 832 }
 833
 834 static inline bool uaddll_overflow(unsigned long long a, unsigned long long b,
 835                                    unsigned long long *res)
 836 {
 837 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 838      return __builtin_uaddll_overflow(a, b, res);
 839 #else
 840      *res = a + b;
 841      return (a + b) < a;
 842 #endif
 843 }
 844
 845 #ifndef __cplusplus
 846 /**
 847  * Overflowing addition
 848  *
 849  * Converts \p a and \p b to the type of \p *r.
 850  * Then computes the sum of both conversions while checking for overflow.
 851  * Finally stores the result in \p *r.
 852  *
 853  * \param a an integer
 854  * \param b an integer
 855  * \param r a pointer to an integer [OUT]
 856  * \retval false The sum did not overflow.
 857  * \retval true The sum overflowed.
 858  */
 859 # define add_overflow(a,b,r) \
 860     _Generic(*(r), \
 861         unsigned: uadd_overflow(a, b, (unsigned *)(r)), \
 862         unsigned long: uaddl_overflow(a, b, (unsigned long *)(r)), \
 863         unsigned long long: uaddll_overflow(a, b, (unsigned long long *)(r)))
 864 #else
 865 static inline bool add_overflow(unsigned a, unsigned b, unsigned *res)
 866 {
 867     return uadd_overflow(a, b, res);
 868 }
 869
 870 static inline bool add_overflow(unsigned long a, unsigned long b,
 871                                 unsigned long *res)
 872 {
 873     return uaddl_overflow(a, b, res);
 874 }
 875
 876 static inline bool add_overflow(unsigned long long a, unsigned long long b,
 877                                 unsigned long long *res)
 878 {
 879     return uaddll_overflow(a, b, res);
 880 }
 881 #endif
 882
 883 #if !(VLC_GCC_VERSION(5,0) || defined(__clang__))
 884 # include <limits.h>
 885 #endif
 886
 887 static inline bool umul_overflow(unsigned a, unsigned b, unsigned *res)
 888 {
 889 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 890      return __builtin_umul_overflow(a, b, res);
 891 #else
 892      *res = a * b;
 893      return b > 0 && a > (UINT_MAX / b);
 894 #endif
 895 }
 896
 897 static inline bool umull_overflow(unsigned long a, unsigned long b,
 898                                   unsigned long *res)
 899 {
 900 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 901      return __builtin_umull_overflow(a, b, res);
 902 #else
 903      *res = a * b;
 904      return b > 0 && a > (ULONG_MAX / b);
 905 #endif
 906 }
 907
 908 static inline bool umulll_overflow(unsigned long long a, unsigned long long b,
 909                                    unsigned long long *res)
 910 {
 911 #if VLC_GCC_VERSION(5,0) || defined(__clang__)
 912      return __builtin_umulll_overflow(a, b, res);
 913 #else
 914      *res = a * b;
 915      return b > 0 && a > (ULLONG_MAX / b);
 916 #endif
 917 }
 918
 919 #ifndef __cplusplus
 920 /**
 921  * Overflowing multiplication
 922  *
 923  * Converts \p a and \p b to the type of \p *r.
 924  * Then computes the product of both conversions while checking for overflow.
 925  * Finally stores the result in \p *r.
 926  *
 927  * \param a an integer
 928  * \param b an integer
 929  * \param r a pointer to an integer [OUT]
 930  * \retval false The product did not overflow.
 931  * \retval true The product overflowed.
 932  */
 933 #define mul_overflow(a,b,r) \
 934     _Generic(*(r), \
 935         unsigned: umul_overflow(a, b, (unsigned *)(r)), \
 936         unsigned long: umull_overflow(a, b, (unsigned long *)(r)), \
 937         unsigned long long: umulll_overflow(a, b, (unsigned long long *)(r)))
 938 #else
 939 static inline bool mul_overflow(unsigned a, unsigned b, unsigned *res)
 940 {
 941     return umul_overflow(a, b, res);
 942 }
 943
 944 static inline bool mul_overflow(unsigned long a, unsigned long b,
 945                                 unsigned long *res)
 946 {
 947     return umull_overflow(a, b, res);
 948 }
 949
 950 static inline bool mul_overflow(unsigned long long a, unsigned long long b,
 951                                 unsigned long long *res)
 952 {
 953     return umulll_overflow(a, b, res);
 954 }
 955 #endif
 956 /** @} */
 957 /** @} */
 958
 959 /* Free and set set the variable to NULL */
 960 #define FREENULL(a) do { free( a ); a = NULL; } while(0)
 961
 962 #define EMPTY_STR(str) (!str || !*str)
 963
 964 #include <vlc_arrays.h>
 965
 966 /* MSB (big endian)/LSB (little endian) conversions - network order is always
 967  * MSB, and should be used for both network communications and files. */
 968
 969 #ifdef WORDS_BIGENDIAN
 970 # define hton16(i) ((uint16_t)(i))
 971 # define hton32(i) ((uint32_t)(i))
 972 # define hton64(i) ((uint64_t)(i))
 973 #else
 974 # define hton16(i) vlc_bswap16(i)
 975 # define hton32(i) vlc_bswap32(i)
 976 # define hton64(i) vlc_bswap64(i)
 977 #endif
 978 #define ntoh16(i) hton16(i)
 979 #define ntoh32(i) hton32(i)
 980 #define ntoh64(i) hton64(i)
 981
 982 /** Reads 16 bits in network byte order */
 983 VLC_USED
 984 static inline uint16_t U16_AT (const void *p)
 985 {
 986     uint16_t x;
 987
 988     memcpy (&x, p, sizeof (x));
 989     return ntoh16 (x);
 990 }
 991
 992 /** Reads 32 bits in network byte order */
 993 VLC_USED
 994 static inline uint32_t U32_AT (const void *p)
 995 {
 996     uint32_t x;
 997
 998     memcpy (&x, p, sizeof (x));
 999     return ntoh32 (x);
1000 }
1001
1002 /** Reads 64 bits in network byte order */
1003 VLC_USED
1004 static inline uint64_t U64_AT (const void *p)
1005 {
1006     uint64_t x;
1007
1008     memcpy (&x, p, sizeof (x));
1009     return ntoh64 (x);
1010 }
1011
1012 #define GetWBE(p)  U16_AT(p)
1013 #define GetDWBE(p) U32_AT(p)
1014 #define GetQWBE(p) U64_AT(p)
1015
1016 /** Reads 16 bits in little-endian order */
1017 VLC_USED
1018 static inline uint16_t GetWLE (const void *p)
1019 {
1020     uint16_t x;
1021
1022     memcpy (&x, p, sizeof (x));
1023 #ifdef WORDS_BIGENDIAN
1024     x = vlc_bswap16 (x);
1025 #endif
1026     return x;
1027 }
1028
1029 /** Reads 32 bits in little-endian order */
1030 VLC_USED
1031 static inline uint32_t GetDWLE (const void *p)
1032 {
1033     uint32_t x;
1034
1035     memcpy (&x, p, sizeof (x));
1036 #ifdef WORDS_BIGENDIAN
1037     x = vlc_bswap32 (x);
1038 #endif
1039     return x;
1040 }
1041
1042 /** Reads 64 bits in little-endian order */
1043 VLC_USED
1044 static inline uint64_t GetQWLE (const void *p)
1045 {
1046     uint64_t x;
1047
1048     memcpy (&x, p, sizeof (x));
1049 #ifdef WORDS_BIGENDIAN
1050     x = vlc_bswap64 (x);
1051 #endif
1052     return x;
1053 }
1054
1055 /** Writes 16 bits in network byte order */
1056 static inline void SetWBE (void *p, uint16_t w)
1057 {
1058     w = hton16 (w);
1059     memcpy (p, &w, sizeof (w));
1060 }
1061
1062 /** Writes 32 bits in network byte order */
1063 static inline void SetDWBE (void *p, uint32_t dw)
1064 {
1065     dw = hton32 (dw);
1066     memcpy (p, &dw, sizeof (dw));
1067 }
1068
1069 /** Writes 64 bits in network byte order */
1070 static inline void SetQWBE (void *p, uint64_t qw)
1071 {
1072     qw = hton64 (qw);
1073     memcpy (p, &qw, sizeof (qw));
1074 }
1075
1076 /** Writes 16 bits in little endian order */
1077 static inline void SetWLE (void *p, uint16_t w)
1078 {
1079 #ifdef WORDS_BIGENDIAN
1080     w = vlc_bswap16 (w);
1081 #endif
1082     memcpy (p, &w, sizeof (w));
1083 }
1084
1085 /** Writes 32 bits in little endian order */
1086 static inline void SetDWLE (void *p, uint32_t dw)
1087 {
1088 #ifdef WORDS_BIGENDIAN
1089     dw = vlc_bswap32 (dw);
1090 #endif
1091     memcpy (p, &dw, sizeof (dw));
1092 }
1093
1094 /** Writes 64 bits in little endian order */
1095 static inline void SetQWLE (void *p, uint64_t qw)
1096 {
1097 #ifdef WORDS_BIGENDIAN
1098     qw = vlc_bswap64 (qw);
1099 #endif
1100     memcpy (p, &qw, sizeof (qw));
1101 }
1102
1103 /* */
1104 #define VLC_UNUSED(x) (void)(x)
1105
1106 /* Stuff defined in src/extras/libc.c */
1107
1108 #if defined(_WIN32)
1109 /* several type definitions */
1110 #   if defined( __MINGW32__ )
1111 #       if !defined( _OFF_T_ )
1112             typedef long long _off_t;
1113             typedef _off_t off_t;
1114 #           define _OFF_T_
1115 #       else
1116 #           ifdef off_t
1117 #               undef off_t
1118 #           endif
1119 #           define off_t long long
1120 #       endif
1121 #   endif
1122
1123 #   ifndef O_NONBLOCK
1124 #       define O_NONBLOCK 0
1125 #   endif
1126
1127 /* the mingw32 swab() and win32 _swab() prototypes expect a char* instead of a
1128    const void* */
1129 #  define swab(a,b,c)  swab((char*) (a), (char*) (b), (c))
1130
1131 #endif /* _WIN32 */
1132
1133 typedef struct {
1134     unsigned num, den;
1135 } vlc_rational_t;
1136
1137 VLC_API bool vlc_ureduce( unsigned *, unsigned *, uint64_t, uint64_t, uint64_t );
1138
1139 #define container_of(ptr, type, member) \
1140     ((type *)(((char *)(ptr)) - offsetof(type, member)))
1141
1142 VLC_USED VLC_MALLOC
1143 static inline void *vlc_alloc(size_t count, size_t size)
1144 {
1145     return mul_overflow(count, size, &size) ? NULL : malloc(size);
1146 }
1147
1148 VLC_USED
1149 static inline void *vlc_reallocarray(void *ptr, size_t count, size_t size)
1150 {
1151     return mul_overflow(count, size, &size) ? NULL : realloc(ptr, size);
1152 }
1153
1154 /*****************************************************************************
1155  * I18n stuff
1156  *****************************************************************************/
1157 VLC_API const char *vlc_gettext(const char *msgid) VLC_FORMAT_ARG(1);
1158 VLC_API const char *vlc_ngettext(const char *s, const char *p, unsigned long n)
1159 VLC_FORMAT_ARG(1) VLC_FORMAT_ARG(2);
1160
1161 #define vlc_pgettext( ctx, id ) \
1162         vlc_pgettext_aux( ctx "\004" id, id )
1163
1164 VLC_FORMAT_ARG(2)
1165 static inline const char *vlc_pgettext_aux( const char *ctx, const char *id )
1166 {
1167     const char *tr = vlc_gettext( ctx );
1168     return (tr == ctx) ? id : tr;
1169 }
1170
1171 /*****************************************************************************
1172  * Loosy memory allocation functions. Do not use in new code.
1173  *****************************************************************************/
1174 static inline void *xmalloc(size_t len)
1175 {
1176     void *ptr = malloc(len);
1177     if (unlikely(ptr == NULL && len > 0))
1178         abort();
1179     return ptr;
1180 }
1181
1182 static inline void *xrealloc(void *ptr, size_t len)
1183 {
1184     void *nptr = realloc(ptr, len);
1185     if (unlikely(nptr == NULL && len > 0))
1186         abort();
1187     return nptr;
1188 }
1189
1190 static inline char *xstrdup (const char *str)
1191 {
1192     char *ptr = strdup (str);
1193     if (unlikely(ptr == NULL))
1194         abort ();
1195     return ptr;
1196 }
1197
1198 /*****************************************************************************
1199  * libvlc features
1200  *****************************************************************************/
1201 VLC_API const char * VLC_CompileBy( void ) VLC_USED;
1202 VLC_API const char * VLC_CompileHost( void ) VLC_USED;
1203 VLC_API const char * VLC_Compiler( void ) VLC_USED;
1204
1205 /*****************************************************************************
1206  * Additional vlc stuff
1207  *****************************************************************************/
1208 #include "vlc_messages.h"
1209 #include "vlc_objects.h"
1210 #include "vlc_variables.h"
1211 #include "vlc_configuration.h"
1212
1213 #if defined( _WIN32 ) || defined( __OS2__ )
1214 #   define DIR_SEP_CHAR '\\'
1215 #   define DIR_SEP "\\"
1216 #   define PATH_SEP_CHAR ';'
1217 #   define PATH_SEP ";"
1218 #else
1219 #   define DIR_SEP_CHAR '/'
1220 #   define DIR_SEP "/"
1221 #   define PATH_SEP_CHAR ':'
1222 #   define PATH_SEP ":"
1223 #endif
1224
1225 #define LICENSE_MSG \
1226   _("This program comes with NO WARRANTY, to the extent permitted by " \
1227     "law.\nYou may redistribute it under the terms of the GNU General " \
1228     "Public License;\nsee the file named COPYING for details.\n" \
1229     "Written by the VideoLAN team; see the AUTHORS file.\n")
1230
1231 #endif /* !VLC_COMMON_H */