-static int write_sparse(int f,char *buf,int len)
-{
- int l1=0,l2=0;
- int ret;
-
- for (l1=0;l1<len && buf[l1]==0;l1++) ;
- for (l2=0;l2<(len-l1) && buf[len-(l2+1)]==0;l2++) ;
-
- last_byte = buf[len-1];
-
- if (l1 == len || l2 > 0)
- last_sparse=1;
-
- if (l1 > 0)
- do_lseek(f,l1,SEEK_CUR);
-
- if (l1 == len)
- return len;
-
- if ((ret=write(f,buf+l1,len-(l1+l2))) != len-(l1+l2)) {
- if (ret == -1 || ret == 0) return ret;
- return (l1+ret);
- }
-
- if (l2 > 0)
- do_lseek(f,l2,SEEK_CUR);
-
- return len;
-}
-
-
-
-int write_file(int f,char *buf,int len)
-{
- int ret = 0;
-
- if (!sparse_files)
- return write(f,buf,len);
-
- while (len>0) {
- int len1 = MIN(len, SPARSE_WRITE_SIZE);
- int r1 = write_sparse(f, buf, len1);
- if (r1 <= 0) {
- if (ret > 0) return ret;
- return r1;
- }
- len -= r1;
- buf += r1;
- ret += r1;
- }
- return ret;
-}
-
-
-static int writefd_unbuffered(int fd,char *buf,int len)
+/* write len bytes to fd, possibly reading from buffer_f_in if set
+ in order to unclog the pipe. don't return until all len
+ bytes have been written */
+static void writefd_unbuffered(int fd,char *buf,int len)