int stream_read_internal(stream_t *s, void *buf, int len)
{
int orig_len = len;
// we will retry even if we already reached EOF previously.
switch(s->type){
case STREAMTYPE_STREAM:
#ifdef CONFIG_NETWORKING
if( s->streaming_ctrl!=NULL && s->streaming_ctrl->streaming_read ) {
len=s->streaming_ctrl->streaming_read(s->fd, buf, len, s->streaming_ctrl);
if (s->streaming_ctrl->status == streaming_stopped_e)
s->eof = 1;
} else
#endif
if (s->fill_buffer)
len = s->fill_buffer(s, buf, len);
else
len = read(s->fd, buf, len);
break;
case STREAMTYPE_DS:
len = demux_read_data((demux_stream_t*)s->priv, buf, len);
break;
default:
len= s->fill_buffer ? s->fill_buffer(s, buf, len) : 0;
}
if(len<=0){
off_t pos = s->pos;
// do not retry if this looks like proper eof
if (s->eof || (s->end_pos && pos == s->end_pos))
goto eof_out;
// dvdnav has some horrible hacks to "suspend" reads,
// we need to skip this code or seeks will hang.
if (s->type == STREAMTYPE_DVDNAV)
goto eof_out;
// just in case this is an error e.g. due to network
// timeout reset and retry
// Seeking is used as a hack to make network streams
// reopen the connection, ideally they would implement
// e.g. a STREAM_CTRL_RECONNECT to do this
s->eof=1;
stream_reset(s);
if (stream_seek_internal(s, pos) >= 0 || s->pos != pos) // seek failed
goto eof_out;
// make sure EOF is set to ensure no endless loops
s->eof=1;
return stream_read_internal(s, buf, orig_len);
eof_out:
s->eof=1;
return 0;
}
// When reading succeeded we are obviously not at eof.
// This e.g. avoids issues with eof getting stuck when lavf seeks in MPEG-TS
s->eof=0;
s->pos+=len;
return len;
}
int stream_seek_long(stream_t *s,off_t pos){
int res;
off_t newpos=0;
// if( mp_msg_test(MSGT_STREAM,MSGL_DBG3) ) printf("seek_long to 0x%X\n",(unsigned int)pos);
s->buf_pos=s->buf_len=0;
if(s->mode == STREAM_WRITE) {
if(!s->seek || !s->seek(s,pos))
return 0;
return 1;
}
if(s->sector_size)
newpos = (pos/s->sector_size)*s->sector_size;
else
newpos = pos&(~((off_t)STREAM_BUFFER_SIZE-1));
if( mp_msg_test(MSGT_STREAM,MSGL_DBG3) ){
mp_msg(MSGT_STREAM,MSGL_DBG3, "s->pos=%"PRIX64" newpos=%"PRIX64" new_bufpos=%"PRIX64" buflen=%X \n",
(int64_t)s->pos,(int64_t)newpos,(int64_t)pos,s->buf_len);
}
pos-=newpos;
res = stream_seek_internal(s, newpos);
if (res >= 0)
return res;
while(s->pos<newpos){
if(stream_fill_buffer(s)<=0) break; // EOF
}
s->eof = 0; // EOF reset when seek succeeds.
while (stream_fill_buffer(s) > 0) {
if(pos<=s->buf_len){
s->buf_pos=pos; // byte position in sector
return 1;
}
pos -= s->buf_len;
}
// Fill failed, but seek still is a success.
s->pos += pos;
s->buf_pos = 0;
s->buf_len = 0;
mp_msg(MSGT_STREAM,MSGL_V,
"stream_seek: Seek to/past EOF: no buffer preloaded.\n");
return 1;
}
int stream_seek_long(stream_t *s, int64_t pos){
int res;
int64_t newpos=0;
// if( mp_msg_test(MSGT_STREAM,MSGL_DBG3) ) printf("seek_long to 0x%X\n",(unsigned int)pos);
s->buf_pos=s->buf_len=0;
if(s->mode == STREAM_WRITE) {
if(!s->seek || !s->seek(s,pos))
return 0;
return 1;
}
if(s->sector_size)
newpos = (pos/s->sector_size)*s->sector_size;
else
newpos = pos&(~((int64_t)STREAM_BUFFER_SIZE-1));
if( mp_msg_test(MSGT_STREAM,MSGL_DBG3) ){
mp_msg(MSGT_STREAM,MSGL_DBG3, "s->pos=%"PRIX64" newpos=%"PRIX64" new_bufpos=%"PRIX64" buflen=%X \n",
(int64_t)s->pos,(int64_t)newpos,(int64_t)pos,s->buf_len);
}
pos-=newpos;
res = stream_seek_internal(s, newpos);
if (res >= 0)
return res;
while(s->pos<newpos){
if(stream_fill_buffer(s)<=0) break; // EOF
}
while(stream_fill_buffer(s) > 0 && pos >= 0) {
if(pos<=s->buf_len){
s->buf_pos=pos; // byte position in sector
return 1;
}
pos -= s->buf_len;
}
// if(pos==s->buf_len) printf("XXX Seek to last byte of file -> EOF\n");
mp_msg(MSGT_STREAM,MSGL_V,"stream_seek: WARNING! Can't seek to 0x%"PRIX64" !\n",(int64_t)(pos+newpos));
return 0;
}
static int stream_reconnect(stream_t *s)
{
#define MAX_RECONNECT_RETRIES 5
#define RECONNECT_SLEEP_MS 1000
int retry = 0;
int64_t pos = s->pos;
// Seeking is used as a hack to make network streams
// reopen the connection, ideally they would implement
// e.g. a STREAM_CTRL_RECONNECT to do this
do {
if (retry >= MAX_RECONNECT_RETRIES)
return 0;
if (retry) usec_sleep(RECONNECT_SLEEP_MS * 1000);
retry++;
s->eof=1;
stream_reset(s);
} while (stream_seek_internal(s, pos) >= 0 || s->pos != pos); // seek failed
return 1;
}
static int cache_fill(cache_vars_t *s)
{
int back,back2,newb,space,len,pos;
off_t read=s->read_filepos;
int read_chunk;
int wraparound_copy = 0;
if(read<s->min_filepos || read>s->max_filepos){
// seek...
mp_msg(MSGT_CACHE,MSGL_DBG2,"Out of boundaries... seeking to 0x%"PRIX64" \n",(int64_t)read);
// drop cache contents only if seeking backward or too much fwd.
// This is also done for on-disk files, since it loses the backseek cache.
// That in turn can cause major bandwidth increase and performance
// issues with e.g. mov or badly interleaved files
if(read<s->min_filepos || read>=s->max_filepos+s->seek_limit)
{
s->offset= // FIXME!?
s->min_filepos=s->max_filepos=read; // drop cache content :(
if(s->stream->eof) stream_reset(s->stream);
stream_seek_internal(s->stream,read);
mp_msg(MSGT_CACHE,MSGL_DBG2,"Seek done. new pos: 0x%"PRIX64" \n",(int64_t)stream_tell(s->stream));
}
}
// calc number of back-bytes:
back=read - s->min_filepos;
if(back<0) back=0; // strange...
if(back>s->back_size) back=s->back_size;
// calc number of new bytes:
newb=s->max_filepos - read;
if(newb<0) newb=0; // strange...
// calc free buffer space:
space=s->buffer_size - (newb+back);
// calc bufferpos:
pos=s->max_filepos - s->offset;
if(pos>=s->buffer_size) pos-=s->buffer_size; // wrap-around
if(space<s->fill_limit){
// printf("Buffer is full (%d bytes free, limit: %d)\n",space,s->fill_limit);
return 0; // no fill...
}
// printf("### read=0x%X back=%d newb=%d space=%d pos=%d\n",read,back,newb,space,pos);
// try to avoid wrap-around. If not possible due to sector size
// do an extra copy.
if(space>s->buffer_size-pos) {
if (s->buffer_size-pos >= s->sector_size) {
space=s->buffer_size-pos;
} else {
space = s->sector_size;
wraparound_copy = 1;
}
}
// limit one-time block size
read_chunk = s->stream->read_chunk;
if (!read_chunk) read_chunk = 4*s->sector_size;
space = FFMIN(space, read_chunk);
#if 1
// back+newb+space <= buffer_size
back2=s->buffer_size-(space+newb); // max back size
if(s->min_filepos<(read-back2)) s->min_filepos=read-back2;
#else
s->min_filepos=read-back; // avoid seeking-back to temp area...
#endif
if (wraparound_copy) {
int to_copy;
len = stream_read_internal(s->stream, s->stream->buffer, space);
to_copy = FFMIN(len, s->buffer_size-pos);
memcpy(s->buffer + pos, s->stream->buffer, to_copy);
memcpy(s->buffer, s->stream->buffer + to_copy, len - to_copy);
} else
len = stream_read_internal(s->stream, &s->buffer[pos], space);
s->eof= !len;
s->max_filepos+=len;
if(pos+len>=s->buffer_size){
// wrap...
s->offset+=s->buffer_size;
}
return len;
}
