FFmpeg/libavutil/common.h

/**
 * @file common.h
 * common internal and external api header.
 */

#ifndef COMMON_H
#define COMMON_H

#ifndef M_PI
#define M_PI    3.14159265358979323846
#endif

#ifdef HAVE_AV_CONFIG_H
/* only include the following when compiling package */
#    include "config.h"

#    include <stdlib.h>
#    include <stdio.h>
#    include <string.h>
#    include <ctype.h>
#    include <limits.h>
#    ifndef __BEOS__
#        include <errno.h>
#    else
#        include "berrno.h"
#    endif
#    include <math.h>
#endif /* HAVE_AV_CONFIG_H */

/* Suppress restrict if it was not defined in config.h.  */
#ifndef restrict
#    define restrict
#endif

#ifndef always_inline
#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)
#    define always_inline __attribute__((always_inline)) inline
#else
#    define always_inline inline
#endif
#endif

#ifndef attribute_used
#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)
#    define attribute_used __attribute__((used))
#else
#    define attribute_used
#endif
#endif

#ifndef attribute_unused
#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)
#    define attribute_unused __attribute__((unused))
#else
#    define attribute_unused
#endif
#endif

#ifndef EMULATE_INTTYPES
#   include <inttypes.h>
#else
    typedef signed char  int8_t;
    typedef signed short int16_t;
    typedef signed int   int32_t;
    typedef unsigned char  uint8_t;
    typedef unsigned short uint16_t;
    typedef unsigned int   uint32_t;
    typedef signed long long   int64_t;
    typedef unsigned long long uint64_t;
#endif /* EMULATE_INTTYPES */

#ifndef PRId64
#define PRId64 "lld"
#endif

#ifndef PRIu64
#define PRIu64 "llu"
#endif

#ifndef PRIx64
#define PRIx64 "llx"
#endif

#ifndef PRId32
#define PRId32 "d"
#endif

#ifndef PRIdFAST16
#define PRIdFAST16 PRId32
#endif

#ifndef PRIdFAST32
#define PRIdFAST32 PRId32
#endif

#ifndef INT16_MIN
#define INT16_MIN       (-0x7fff-1)
#endif

#ifndef INT16_MAX
#define INT16_MAX       0x7fff
#endif

#ifndef INT32_MIN
#define INT32_MIN       (-0x7fffffff-1)
#endif

#ifndef INT32_MAX
#define INT32_MAX       0x7fffffff
#endif

#ifndef UINT32_MAX
#define UINT32_MAX      0xffffffff
#endif

#ifndef INT64_MIN
#define INT64_MIN       (-0x7fffffffffffffffLL-1)
#endif

#ifndef INT64_MAX
#define INT64_MAX int64_t_C(9223372036854775807)
#endif

#ifndef UINT64_MAX
#define UINT64_MAX uint64_t_C(0xFFFFFFFFFFFFFFFF)
#endif

#ifdef EMULATE_FAST_INT
typedef signed char int_fast8_t;
typedef signed int  int_fast16_t;
typedef signed int  int_fast32_t;
typedef unsigned char uint_fast8_t;
typedef unsigned int  uint_fast16_t;
typedef unsigned int  uint_fast32_t;
typedef uint64_t      uint_fast64_t;
#endif

#ifndef INT_BIT
#    if INT_MAX != 2147483647
#        define INT_BIT 64
#    else
#        define INT_BIT 32
#    endif
#endif

#ifndef int64_t_C
#define int64_t_C(c)     (c ## LL)
#define uint64_t_C(c)    (c ## ULL)
#endif

#if defined(__MINGW32__) && !defined(BUILD_AVUTIL) && defined(BUILD_SHARED_AV)
#  define FF_IMPORT_ATTR __declspec(dllimport)
#else
#  define FF_IMPORT_ATTR
#endif


#ifdef HAVE_AV_CONFIG_H
/* only include the following when compiling package */
#    include "internal.h"
#endif

//rounded divison & shift
#define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
/* assume b>0 */
#define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
#define ABS(a) ((a) >= 0 ? (a) : (-(a)))

#define FFMAX(a,b) ((a) > (b) ? (a) : (b))
#define FFMIN(a,b) ((a) > (b) ? (b) : (a))

/* misc math functions */
extern FF_IMPORT_ATTR const uint8_t ff_log2_tab[256];

static inline int av_log2(unsigned int v)
{
    int n;

    n = 0;
    if (v & 0xffff0000) {
        v >>= 16;
        n += 16;
    }
    if (v & 0xff00) {
        v >>= 8;
        n += 8;
    }
    n += ff_log2_tab[v];

    return n;
}

static inline int av_log2_16bit(unsigned int v)
{
    int n;

    n = 0;
    if (v & 0xff00) {
        v >>= 8;
        n += 8;
    }
    n += ff_log2_tab[v];

    return n;
}

/* median of 3 */
static inline int mid_pred(int a, int b, int c)
{
#if 0
    int t= (a-b)&((a-b)>>31);
    a-=t;
    b+=t;
    b-= (b-c)&((b-c)>>31);
    b+= (a-b)&((a-b)>>31);

    return b;
#else
    if(a>b){
        if(c>b){
            if(c>a) b=a;
            else    b=c;
        }
    }else{
        if(b>c){
            if(c>a) b=c;
            else    b=a;
        }
    }
    return b;
#endif
}

/**
 * clip a signed integer value into the amin-amax range
 * @param a value to clip
 * @param amin minimum value of the clip range
 * @param amax maximum value of the clip range
 * @return cliped value
 */
static inline int clip(int a, int amin, int amax)
{
    if (a < amin)      return amin;
    else if (a > amax) return amax;
    else               return a;
}

/**
 * clip a signed integer value into the 0-255 range
 * @param a value to clip
 * @return cliped value
 */
static inline uint8_t clip_uint8(int a)
{
    if (a&(~255)) return (-a)>>31;
    else          return a;
}

/* math */
int64_t ff_gcd(int64_t a, int64_t b);

/**
 * converts fourcc string to int
 */
static inline int ff_get_fourcc(const char *s){
#ifdef HAVE_AV_CONFIG_H
    assert( strlen(s)==4 );
#endif

    return (s[0]) + (s[1]<<8) + (s[2]<<16) + (s[3]<<24);
}

#define MKTAG(a,b,c,d) (a | (b << 8) | (c << 16) | (d << 24))
#define MKBETAG(a,b,c,d) (d | (c << 8) | (b << 16) | (a << 24))


#define GET_UTF8(val, GET_BYTE, ERROR)\
    val= GET_BYTE;\
    {\
        int ones= 7 - av_log2(val ^ 255);\
        if(ones==1)\
            ERROR\
        val&= 127>>ones;\
        while(--ones > 0){\
            int tmp= GET_BYTE - 128;\
            if(tmp>>6)\
                ERROR\
            val= (val<<6) + tmp;\
        }\
    }

#if defined(ARCH_X86) || defined(ARCH_X86_64) || defined(ARCH_POWERPC)
#if defined(ARCH_X86_64)
static inline uint64_t read_time(void)
{
        uint64_t a, d;
        asm volatile(   "rdtsc\n\t"
                : "=a" (a), "=d" (d)
        );
        return (d << 32) | (a & 0xffffffff);
}
#elif defined(ARCH_X86)
static inline long long read_time(void)
{
        long long l;
        asm volatile(   "rdtsc\n\t"
                : "=A" (l)
        );
        return l;
}
#else //FIXME check ppc64
static inline uint64_t read_time(void)
{
    uint32_t tbu, tbl, temp;

     /* from section 2.2.1 of the 32-bit PowerPC PEM */
     __asm__ __volatile__(
         "1:\n"
         "mftbu  %2\n"
         "mftb   %0\n"
         "mftbu  %1\n"
         "cmpw   %2,%1\n"
         "bne    1b\n"
     : "=r"(tbl), "=r"(tbu), "=r"(temp)
     :
     : "cc");

     return (((uint64_t)tbu)<<32) | (uint64_t)tbl;
}
#endif

#define START_TIMER \
uint64_t tend;\
uint64_t tstart= read_time();\

#define STOP_TIMER(id) \
tend= read_time();\
{\
  static uint64_t tsum=0;\
  static int tcount=0;\
  static int tskip_count=0;\
  if(tcount<2 || tend - tstart < 8*tsum/tcount){\
      tsum+= tend - tstart;\
      tcount++;\
  }else\
      tskip_count++;\
  if(256*256*256*64%(tcount+tskip_count)==0){\
      av_log(NULL, AV_LOG_DEBUG, "%"PRIu64" dezicycles in %s, %d runs, %d skips\n", tsum*10/tcount, id, tcount, tskip_count);\
  }\
}
#else
#define START_TIMER
#define STOP_TIMER(id) {}
#endif

/* memory */
void *av_malloc(unsigned int size);
void *av_realloc(void *ptr, unsigned int size);
void av_free(void *ptr);

#endif /* COMMON_H */