add loop

io/iob_send.c

@@ -24,62 +24,67 @@ int64 iob_send(int64 s,io_batch* b) {
 
   if (b->bytesleft==0) return 0;
   last=array_start(&b->b)+array_bytes(&b->b);
-  if (!(e=array_get(&b->b,sizeof(io_entry),b->next)))
-    return -1;		/* can't happen error */
   v=alloca(b->bufs*sizeof(struct iovec));
+  for (;;) {
+    if (!(e=array_get(&b->b,sizeof(io_entry),b->next)))
+      return -1;		/* can't happen error */
 #ifdef BSD_SENDFILE
-  /* BSD sendfile can send headers and trailers.  If we run on BSD, we
-   * should try to exploit this. */
-  headers=trailers=0;
+    /* BSD sendfile can send headers and trailers.  If we run on BSD, we
+    * should try to exploit this. */
+    headers=trailers=0;
 #endif
-  for (i=0; e+i<last; ++i) {
-    if (e[i].type==FROMFILE) break;
-    v[i].iov_base=e[i].buf+e[i].offset;
-    v[i].iov_len=e[i].n-e[i].offset;
-  }
-  headers=i;
-#ifdef BSD_SENDFILE
-  if (e[i].type==FROMFILE) {
-    off_t sbytes;
-    struct sf_hdtr hdr;
-    int r;
-    for (++i; e+i<last; ++i) {
+    for (i=0; e+i<last; ++i) {
       if (e[i].type==FROMFILE) break;
-      v[i-1].iov_base=e[i].buf+e[i].offset;
-      v[i-1].iov_len=e[i].n-e[i].offset;
-      ++trailers;
+      v[i].iov_base=e[i].buf+e[i].offset;
+      v[i].iov_len=e[i].n-e[i].offset;
     }
-    hdr.headers=v; hdr.hdr_cnt=headers;
-    hdr.trailers=v+headers; hdr.trl_cnt=trailers;
-    r=sendfile(e[headers].fd,s,e[headers].offset,e[headers].n,&hdr,&sbytes,0);
-    if (r==0)
-      sent=b->bytesleft;
-    else if (r==-1 && errno==EAGAIN)
-      sent=sbytes;
-    else
-      sent=-1;
-  } else
-    sent=writev(s,v,headers);
+    headers=i;
+#ifdef BSD_SENDFILE
+    if (e[i].type==FROMFILE) {
+      off_t sbytes;
+      struct sf_hdtr hdr;
+      int r;
+      for (++i; e+i<last; ++i) {
+	if (e[i].type==FROMFILE) break;
+	v[i-1].iov_base=e[i].buf+e[i].offset;
+	v[i-1].iov_len=e[i].n-e[i].offset;
+	++trailers;
+      }
+      hdr.headers=v; hdr.hdr_cnt=headers;
+      hdr.trailers=v+headers; hdr.trl_cnt=trailers;
+      r=sendfile(e[headers].fd,s,e[headers].offset,e[headers].n,&hdr,&sbytes,0);
+      if (r==0)
+	sent=b->bytesleft;
+      else if (r==-1 && errno==EAGAIN)
+	sent=sbytes;
+      else
+	sent=-1;
+    } else
+      sent=writev(s,v,headers);
 #else
-  if (headers)
-    sent=writev(s,v,headers);
-  else
-    sent=io_sendfile(s,e->fd,e->offset,e->n);
+    if (headers)
+      sent=writev(s,v,headers);
+    else
+      sent=io_sendfile(s,e->fd,e->offset,e->n);
 #endif
-  if (sent==b->bytesleft)
-    b->bytesleft=0;
-  else if (sent>0) {
-    int64 rest=sent;
-    b->bytesleft-=rest;
-    for (i=0; e+i<last; ++i) {
-      if (e[i].n-e[i].offset<rest) {
-	rest-=e[i].n-e[i].offset;
-	++b->next;
-      } else {
-	e[i].offset+=rest;
-	break;
+    if (sent==b->bytesleft) {
+      b->bytesleft=0;
+      break;
+    } else if (sent>0) {
+      int64 rest=sent;
+      b->bytesleft-=rest;
+      for (i=0; e+i<last; ++i) {
+	if (e[i].n-e[i].offset<=rest) {
+	  rest-=e[i].n-e[i].offset;
+	  ++b->next;
+	  if (!rest) break;
+	} else {
+	  e[i].offset+=rest;
+	  goto abort;
+	}
       }
-    }
+    } else break;
   }
+abort:
   return sent;
 }