/*
?*??avilib.c
?*
?*??Copyright?（C）?Thomas?謘treich?-?June?2001
?*??multiple?audio?track?support?Copyright?（C）?2002?Thomas?謘treich?
?*
?*??Original?code:
?*??Copyright?（C）?1999?Rainer?Johanni??
?*
?*??This?file?is?part?of?transcode?a?linux?video?stream?processing?tool
?*??????
?*??transcode?is?free?software;?you?can?redistribute?it?and/or?modify
?*??it?under?the?terms?of?the?GNU?General?Public?License?as?published?by
?*??the?Free?Software?Foundation;?either?version?2?or?（at?your?option）
?*??any?later?version.
?*???
?*??transcode?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?General?Public?License?for?more?details.
?*???
?*??You?should?have?received?a?copy?of?the?GNU?General?Public?License
?*??along?with?GNU?Make;?see?the?file?COPYING.??If?not?write?to
?*??the?Free?Software?Foundation?675?Mass?Ave?Cambridge?MA?02139?USA.?
?*
?*/

#include?“avilib.h“
//#include?

#define?INFO_LIST

/*?The?following?variable?indicates?the?kind?of?error?*/

long?AVI_errno;

#define?MAX_INFO_STRLEN?64
static?char?id_str[MAX_INFO_STRLEN];

#define?frame_RATE_SCALE?1000000

#ifndef?PACKAGE
#define?PACKAGE?“my“
#define?VERSION?“0.00“
#endif

#ifndef?O_BINARY
/*?win32?wants?a?binary?flag?to?open（）;?this?sets?it?to?null
???on?platforms?that?don‘t?have?it.?*/
#define?O_BINARY?0
#endif

/*******************************************************************
?*?????????????????????????????????????????????????????????????????*
?*????Utilities?for?writing?an?AVI?File????????????????????????????*
?*?????????????????????????????????????????????????????????????????*
?*******************************************************************/

static?size_t?avi_read（int?fd?char?*buf?size_t?len）
{
???size_t?n?=?0;
???size_t?r?=?0;

???while?（r???????n?=?read?（fd?buf?+?r?len?-?r）;

??????if?（n?<=?0）
	??return?r;
??????r?+=?n;
???}

???return?r;
}

static?size_t?avi_write?（int?fd?char?*buf?size_t?len）
{
???size_t?n?=?0;
???size_t?r?=?0;

???while?（r???????n?=?write?（fd?buf?+?r?len?-?r）;
??????if?（n??????????return?n;
??????
??????r?+=?n;
???}
???return?r;
}

/*?HEADERBYTES:?The?number?of?bytes?to?reserve?for?the?header?*/

#define?HEADERBYTES?2048

/*?AVI_MAX_LEN:?The?maximum?length?of?an?AVI?file?we?stay?a?bit?below
????the?2GB?limit?（Remember:?2*10^9?is?smaller?than?2?GB）?*/

#define?AVI_MAX_LEN?（UINT_MAX-（1<<20）*16-HEADERBYTES）

#define?PAD_EVEN（x）?（?（（x）+1）?&?~1?）


/*?Copy?n?into?dst?as?a?4?byte?little?endian?number.
???Should?also?work?on?big?endian?machines?*/

static?void?long2str（unsigned?char?*dst?int?n）
{
???dst[0]?=?（n????）&0xff;
???dst[1]?=?（n>>?8）&0xff;
???dst[2]?=?（n>>16）&0xff;
???dst[3]?=?（n>>24）&0xff;
}

/*?Convert?a?string?of?4?or?2?bytes?to?a?number
???also?working?on?big?endian?machines?*/

static?unsigned?long?str2ulong（unsigned?char?*str）
{
???return?（?str[0]?|?