sys/src/libbio/bwrite.c

   1 #include        <u.h>
   2 #include        <libc.h>
   3 #include        <bio.h>
   4
   5 long
   6 Bwrite(Biobufhdr *bp, void *ap, long count)
   7 {
   8         long c;
   9         uchar *p;
  10         int i, n, oc;
  11         char errbuf[ERRMAX];
  12
  13         p = ap;
  14         c = count;
  15         oc = bp->ocount;
  16
  17         while(c > 0) {
  18                 n = -oc;
  19                 if(n > c)
  20                         n = c;
  21                 if(n == 0) {
  22                         if(bp->state != Bwactive)
  23                                 return Beof;
  24                         i = bp->iof(bp, bp->bbuf, bp->bsize);
  25                         if(i != bp->bsize) {
  26                                 errstr(errbuf, sizeof errbuf);
  27                                 if(strstr(errbuf, "interrupt") == nil) {
  28                                         bp->state = Binactive;
  29                                         Berror(bp, "write error: %s", errbuf);
  30                                 }
  31                                 errstr(errbuf, sizeof errbuf);
  32                                 return Beof;
  33                         }
  34                         bp->offset += i;
  35                         oc = -bp->bsize;
  36                         continue;
  37                 }
  38                 memmove(bp->ebuf+oc, p, n);
  39                 oc += n;
  40                 c -= n;
  41                 p += n;
  42         }
  43         bp->ocount = oc;
  44         return count-c;
  45 }