PeerStreamer

/*

 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file common.h

 * common internal and external api header.

 */

#ifndef FFMPEG_COMMON_H

#define FFMPEG_COMMON_H

#include <inttypes.h>

#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>

#    include <errno.h>

#    include <math.h>

#endif /* HAVE_AV_CONFIG_H */

#ifndef av_always_inline

#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)

#    define av_always_inline __attribute__((always_inline)) inline

#else

#    define av_always_inline inline

#endif

#endif

#ifndef av_noinline

#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)

#    define av_noinline __attribute__((noinline))

#else

#    define av_noinline

#endif

#endif

#ifdef HAVE_AV_CONFIG_H

#    include "internal.h"

#endif /* HAVE_AV_CONFIG_H */

#ifndef attribute_deprecated

#if defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)

#    define attribute_deprecated __attribute__((deprecated))

#else

#    define attribute_deprecated

#endif

#endif

#ifndef av_unused

#if defined(__GNUC__)

#    define av_unused __attribute__((unused))

#else

#    define av_unused

#endif

#endif

#include "mem.h"

//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 FFABS(a) ((a) >= 0 ? (a) : (-(a)))

#define FFSIGN(a) ((a) > 0 ? 1 : -1)

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

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

#define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)

/* misc math functions */

extern const uint8_t ff_log2_tab[256];

static inline int av_log2(unsigned int v)

{

    int 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 = 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)

{

#ifdef HAVE_CMOV

    int i=b;

    asm volatile(

        "cmp    %2, %1 \n\t"

        "cmovg  %1, %0 \n\t"

        "cmovg  %2, %1 \n\t"

        "cmp    %3, %1 \n\t"

        "cmovl  %3, %1 \n\t"

        "cmp    %1, %0 \n\t"

        "cmovg  %1, %0 \n\t"

        :"+&r"(i), "+&r"(a)

        :"r"(b), "r"(c)

    );

    return i;

#elif 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 clipped value

 */

static inline int av_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 clipped value

 */

static inline uint8_t av_clip_uint8(int a)

{

    if (a&(~255)) return (-a)>>31;

    else          return a;

}

/**

 * clip a signed integer value into the -32768,32767 range

 * @param a value to clip

 * @return clipped value

 */

static inline int16_t av_clip_int16(int a)

{

    if ((a+32768) & ~65535) return (a>>31) ^ 32767;

    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))

/*!

 * \def GET_UTF8(val, GET_BYTE, ERROR)

 * converts a UTF-8 character (up to 4 bytes long) to its 32-bit UCS-4 encoded form

 * \param val is the output and should be of type uint32_t. It holds the converted

 * UCS-4 character and should be a left value.

 * \param GET_BYTE gets UTF-8 encoded bytes from any proper source. It can be

 * a function or a statement whose return value or evaluated value is of type

 * uint8_t. It will be executed up to 4 times for values in the valid UTF-8 range,

 * and up to 7 times in the general case.

 * \param ERROR action that should be taken when an invalid UTF-8 byte is returned

 * from GET_BYTE. It should be a statement that jumps out of the macro,

 * like exit(), goto, return, break, or continue.

 */

#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;\

        }\

    }

/*!

 * \def PUT_UTF8(val, tmp, PUT_BYTE)

 * converts a 32-bit unicode character to its UTF-8 encoded form (up to 4 bytes long).

 * \param val is an input only argument and should be of type uint32_t. It holds

 * a ucs4 encoded unicode character that is to be converted to UTF-8. If

 * val is given as a function it's executed only once.

 * \param tmp is a temporary variable and should be of type uint8_t. It

 * represents an intermediate value during conversion that is to be

 * outputted by PUT_BYTE.

 * \param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.

 * It could be a function or a statement, and uses tmp as the input byte.

 * For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be

 * executed up to 4 times for values in the valid UTF-8 range and up to

 * 7 times in the general case, depending on the length of the converted

 * unicode character.

 */

#define PUT_UTF8(val, tmp, PUT_BYTE)\

    {\

        int bytes, shift;\

        uint32_t in = val;\

        if (in < 0x80) {\

            tmp = in;\

            PUT_BYTE\

        } else {\

            bytes = (av_log2(in) + 4) / 5;\

            shift = (bytes - 1) * 6;\

            tmp = (256 - (256 >> bytes)) | (in >> shift);\

            PUT_BYTE\

            while (shift >= 6) {\

                shift -= 6;\

                tmp = 0x80 | ((in >> shift) & 0x3f);\

                PUT_BYTE\

            }\

        }\

    }

#if defined(ARCH_X86) || defined(ARCH_POWERPC) || defined(ARCH_BFIN)

#define AV_READ_TIME read_time

#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_32)

static inline long long read_time(void)

{

    long long l;

    asm volatile("rdtsc\n\t"

                 : "=A" (l));

    return l;

}

#elif ARCH_BFIN

static inline uint64_t read_time(void)

{

    union {

        struct {

            unsigned lo;

            unsigned hi;

        } p;

        unsigned long long c;

    } t;

    asm volatile ("%0=cycles; %1=cycles2;" : "=d" (t.p.lo), "=d" (t.p.hi));

    return t.c;

}

#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

#elif defined(HAVE_GETHRTIME)

#define AV_READ_TIME gethrtime

#endif

#ifdef AV_READ_TIME

#define START_TIMER \

uint64_t tend;\

uint64_t tstart= AV_READ_TIME();\

#define STOP_TIMER(id) \

tend= AV_READ_TIME();\

{\

    static uint64_t tsum=0;\

    static int tcount=0;\

    static int tskip_count=0;\

    if(tcount<2 || tend - tstart < FFMAX(8*tsum/tcount, 2000)){\

        tsum+= tend - tstart;\

        tcount++;\

    }else\

        tskip_count++;\

    if(((tcount+tskip_count)&(tcount+tskip_count-1))==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

#endif /* FFMPEG_COMMON_H */