/*
  * 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 libavutil/common.h

  * common internal and external API header

  */
 

 #ifndef AVUTIL_COMMON_H
 #define AVUTIL_COMMON_H

 #include <ctype.h>
 #include <errno.h>

 #include <inttypes.h>

 #include <limits.h>
 #include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #ifdef __GNUC__
 #    define AV_GCC_VERSION_AT_LEAST(x,y) (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y)
 #else
 #    define AV_GCC_VERSION_AT_LEAST(x,y) 0
 #endif

 #ifndef av_always_inline

 #if AV_GCC_VERSION_AT_LEAST(3,1)

 #    define av_always_inline __attribute__((always_inline)) inline
 #else
 #    define av_always_inline inline

 #endif
 #endif
 
 #ifndef av_noinline

 #if AV_GCC_VERSION_AT_LEAST(3,1)

 #    define av_noinline __attribute__((noinline))
 #else

 #    define av_noinline

 #endif
 #endif
 

 #ifndef av_pure

 #if AV_GCC_VERSION_AT_LEAST(3,1)

 #    define av_pure __attribute__((pure))
 #else
 #    define av_pure
 #endif
 #endif
 
 #ifndef av_const

 #if AV_GCC_VERSION_AT_LEAST(2,6)

 #    define av_const __attribute__((const))
 #else
 #    define av_const
 #endif
 #endif
 

 #ifndef av_cold

 #if (!defined(__ICC) || __ICC > 1100) && AV_GCC_VERSION_AT_LEAST(4,3)

 #    define av_cold __attribute__((cold))
 #else
 #    define av_cold
 #endif
 #endif
 

 #ifndef av_flatten

 #if AV_GCC_VERSION_AT_LEAST(4,1)

 #    define av_flatten __attribute__((flatten))
 #else
 #    define av_flatten
 #endif
 #endif
 

 #ifndef attribute_deprecated

 #if AV_GCC_VERSION_AT_LEAST(3,1)

 #    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
 

 #ifndef av_uninit

 #if defined(__GNUC__) && !defined(__ICC)

 #    define av_uninit(x) x=x
 #else
 #    define av_uninit(x) x
 #endif
 #endif
 

 //rounded division & 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 FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)

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

 #define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)

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

 #define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))

 /* misc math functions */

 extern const uint8_t ff_log2_tab[256];

 static inline av_const 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 av_const int av_log2_16bit(unsigned int v)

 {

     int n = 0;

     if (v & 0xff00) {
         v >>= 8;
         n += 8;

     }

     n += ff_log2_tab[v];
 

     return n;
 }
 

 /**

  * Clips 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 av_const int av_clip(int a, int amin, int amax)

 {

     if      (a < amin) return amin;

     else if (a > amax) return amax;
     else               return a;

 }
 

 /**

  * Clips a signed integer value into the 0-255 range.

  * @param a value to clip

  * @return clipped value

  */

 static inline av_const uint8_t av_clip_uint8(int a)

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

 /**

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

  * @param a value to clip
  * @return clipped value
  */

 static inline av_const int16_t av_clip_int16(int a)

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

 /**

  * Clips a float 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 av_const float av_clipf(float a, float amin, float amax)
 {
     if      (a < amin) return amin;
     else if (a > amax) return amax;
     else               return a;
 }
 

 #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 UCS-4 encoded Unicode character that is to be converted to UTF-8. If
  * val is given as a function it is 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

  * output 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\
             }\
         }\
     }
 

 #include "mem.h"
 

 #ifdef HAVE_AV_CONFIG_H

 #    include "config.h"

 #    include "internal.h"
 #endif /* HAVE_AV_CONFIG_H */
 

 #endif /* AVUTIL_COMMON_H */