cache prg for slow stdin playback

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@918 b3059339-0415-0410-9bf9-f77b7e298cf2

TOOLS/cache.c

@@ -0,0 +1,121 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+//int open(const char *pathname, int flags);
+
+
+#define BUFFSIZE (4*65536)
+#define NUM_BUFS (16)
+
+unsigned char *buffer[NUM_BUFS];
+
+unsigned int buf_read=0;
+unsigned int buf_write=0;
+unsigned int buf_read_pos=0;
+unsigned int buf_write_pos=0;
+int full_buffers=0;
+
+int main(int argc,char* argv[]){
+
+           fd_set rfds;
+           fd_set wfds;
+           struct timeval tv;
+           int retval;
+	   int i;
+//	   int empty=1;
+	   int can_read=1;
+	   int eof=0;
+	   int in_fd=0; // stdin
+	   
+	   if(argc>1) in_fd=open(argv[1],O_RDONLY|O_NDELAY);
+	   
+	   for(i=0;i<NUM_BUFS;i++) buffer[i]=malloc(BUFFSIZE);
+
+while(1){
+           /* Watch stdin (fd 0) to see when it has input. */
+           FD_ZERO(&rfds); if(can_read){ FD_SET(in_fd, &rfds);}
+           FD_ZERO(&wfds); FD_SET(1, &wfds);
+           /* Wait up to five seconds. */
+           tv.tv_sec = 1;
+           tv.tv_usec = 0;
+           retval = select((in_fd<1?1:in_fd)+1, &rfds, &wfds, NULL, &tv);
+           /* Don't rely on the value of tv now! */
+
+           if (retval){
+	       if(FD_ISSET(in_fd, &rfds) || !full_buffers){
+	               fprintf(stderr,"\n%d  r",full_buffers);fflush(stderr);
+		   if(full_buffers==NUM_BUFS){
+		       // buffer is full!
+		       can_read=0;
+	               fprintf(stderr,"\n%d  full!\n",full_buffers);fflush(stderr);
+		   } else {
+		       // we can read input.
+		       int len=BUFFSIZE-buf_read_pos;
+	               fprintf(stderr,"R");fflush(stderr);
+		       len=read(in_fd,buffer[buf_read]+buf_read_pos,len);
+	               fprintf(stderr,"(%d)\n",len);fflush(stderr);
+		       if(len>0){
+		           buf_read_pos+=len;
+			   if(buf_read_pos>=BUFFSIZE){
+			       // block is full, find next!
+			       buf_read=(buf_read+1)%NUM_BUFS;
+			       ++full_buffers;
+			       buf_read_pos=0;
+	                       fprintf(stderr,"+");fflush(stderr);
+			   }
+		       } else {
+		           eof=1;
+		       }
+		   }
+	       }
+	       if(FD_ISSET(1, &wfds)){
+	               fprintf(stderr,"\n%d  w",full_buffers);fflush(stderr);
+		   if(full_buffers==0){
+		       if(eof){
+		           // flush buffer!
+			   int pos=0;
+			   int len;
+	                   fprintf(stderr,"\nf");fflush(stderr);
+			   while((len=buf_read_pos-pos)>0){
+			       len=write(1,buffer[buf_write]+pos,len);
+	               fprintf(stderr,"(%d)",len);fflush(stderr);
+			       if(len<=0) break;
+			       pos+=len;
+			   }
+		           exit(1);
+		       }
+		       fprintf(stderr," empty");fflush(stderr);
+		       //empty=1; // we must fill buffers!
+		   } else {
+		       // yeah, we can read from the buffer!
+		       int len=BUFFSIZE-buf_write_pos;
+	               fprintf(stderr,"W");fflush(stderr);
+		       len=write(1,buffer[buf_write]+buf_write_pos,len);
+	               fprintf(stderr,"(%d)",len);fflush(stderr);
+		       if(len>0){
+		           buf_write_pos+=len;
+			   if(buf_write_pos>=BUFFSIZE){
+			       // block is empty, find next!
+			       buf_write=(buf_write+1)%NUM_BUFS;
+			       --full_buffers;
+			       buf_write_pos=0;
+	                       fprintf(stderr,"-");fflush(stderr);
+			       can_read=1;
+			   }
+		       }
+		   }
+	       }
+	   } else {
+	           fprintf(stderr,".");fflush(stderr);
+	   }
+}
+
+return 0;
+}
+