mpv/stream.c

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4.3 KiB
C
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#include "vcd_read.c"
//=================== STREAMER =========================
#define STREAM_BUFFER_SIZE 4096
#define STREAMTYPE_FILE 0
#define STREAMTYPE_VCD 1
typedef struct {
int fd;
long pos;
int eof;
int type; // 0=file 1=VCD
unsigned int buf_pos,buf_len;
unsigned char buffer[STREAM_BUFFER_SIZE];
} stream_t;
int stream_fill_buffer(stream_t *s){
int len;
if(s->eof){ s->buf_pos=s->buf_len=0; return 0; }
switch(s->type){
case STREAMTYPE_FILE:
len=read(s->fd,s->buffer,STREAM_BUFFER_SIZE);break;
case STREAMTYPE_VCD:
#ifdef VCD_CACHE
len=vcd_cache_read(s->fd,s->buffer);break;
#else
len=vcd_read(s->fd,s->buffer);break;
#endif
default: len=0;
}
if(len<=0){ s->eof=1; s->buf_pos=s->buf_len=0; return 0; }
s->buf_pos=0;
s->buf_len=len;
s->pos+=len;
// printf("[%d]",len);fflush(stdout);
return len;
}
inline unsigned int stream_read_char(stream_t *s){
return (s->buf_pos<s->buf_len)?s->buffer[s->buf_pos++]:
(stream_fill_buffer(s)?s->buffer[s->buf_pos++]:0);
// if(s->buf_pos<s->buf_len) return s->buffer[s->buf_pos++];
// stream_fill_buffer(s);
// if(s->buf_pos<s->buf_len) return s->buffer[s->buf_pos++];
// return 0; // EOF
}
inline unsigned int stream_read_word(stream_t *s){
int x,y;
x=stream_read_char(s);
y=stream_read_char(s);
return (x<<8)|y;
}
inline unsigned int stream_read_dword(stream_t *s){
unsigned int y;
y=stream_read_char(s);
y=(y<<8)|stream_read_char(s);
y=(y<<8)|stream_read_char(s);
y=(y<<8)|stream_read_char(s);
return y;
}
inline unsigned int stream_read_word_le(stream_t *s){
int x,y;
x=stream_read_char(s);
y=stream_read_char(s);
return (y<<8)|x;
}
inline unsigned int stream_read_dword_le(stream_t *s){
unsigned int y;
y=stream_read_char(s);
y|=stream_read_char(s)<<8;
y|=stream_read_char(s)<<16;
y|=stream_read_char(s)<<24;
return y;
}
inline void stream_read(stream_t *s,char* mem,int len){
while(len>0){
int x;
x=s->buf_len-s->buf_pos;
if(x==0){
if(!stream_fill_buffer(s)) return; // EOF
x=s->buf_len-s->buf_pos;
}
if(s->buf_pos>s->buf_len) printf("stream_read: WARNING! s->buf_pos>s->buf_len\n");
if(x>len) x=len;
memcpy(mem,&s->buffer[s->buf_pos],x);
s->buf_pos+=x; mem+=x; len-=x;
}
}
inline int stream_eof(stream_t *s){
return s->eof;
}
inline int stream_tell(stream_t *s){
return s->pos+s->buf_pos-s->buf_len;
}
inline int stream_seek(stream_t *s,unsigned int pos){
unsigned int newpos;
if(verbose>=3) printf("seek to 0x%X\n",pos);
if(pos<s->pos){
int x=pos-(s->pos-s->buf_len);
if(x>=0){
s->buf_pos=x;
// putchar('*');fflush(stdout);
return 1;
}
}
if(verbose>=3){
printf("s->pos=%X newpos=%X new_bufpos=%X buflen=%X \n",
s->pos,newpos,pos,s->buf_len);
}
s->buf_pos=s->buf_len=0;
switch(s->type){
case STREAMTYPE_FILE:
newpos=pos&(~4095);break;
case STREAMTYPE_VCD:
newpos=(pos/VCD_SECTOR_DATA)*VCD_SECTOR_DATA;break;
}
pos-=newpos;
if(newpos==0 || newpos!=s->pos){
s->pos=newpos; // real seek
switch(s->type){
case STREAMTYPE_FILE:
if(lseek(s->fd,s->pos,SEEK_SET)<0) s->eof=1;
break;
case STREAMTYPE_VCD:
#ifdef VCD_CACHE
vcd_cache_seek(s->pos/VCD_SECTOR_DATA);
#else
vcd_set_msf(s->pos/VCD_SECTOR_DATA);
#endif
break;
}
// putchar('.');fflush(stdout);
//} else {
// putchar('%');fflush(stdout);
}
stream_fill_buffer(s);
if(pos>=0 && pos<s->buf_len){
s->buf_pos=pos; // byte position in sector
return 1;
}
printf("stream_seek: WARNING! Can't seek to 0x%X !\n",pos+newpos);
return 0;
}
inline void stream_skip(stream_t *s,int len){
if(len<0 || len>2*STREAM_BUFFER_SIZE){
// negative or big skip!
stream_seek(s,stream_tell(s)+len);
return;
}
while(len>0){
int x=s->buf_len-s->buf_pos;
if(x==0){
if(!stream_fill_buffer(s)) return; // EOF
x=s->buf_len-s->buf_pos;
}
if(x>len) x=len;
//memcpy(mem,&s->buf[s->buf_pos],x);
s->buf_pos+=x; len-=x;
}
}
void stream_reset(stream_t *s){
if(s->eof){
s->pos=0; //ftell(f);
// s->buf_pos=s->buf_len=0;
s->eof=0;
}
//stream_seek(s,0);
}
stream_t* new_stream(int fd,int type){
stream_t *s=malloc(sizeof(stream_t));
s->fd=fd;
s->type=type;
s->buf_pos=s->buf_len=0;
stream_reset(s);
return s;
}
void free_stream(stream_t *s){
free(s);
}