Merge pull request #1787 from davidBar-On/issue-1707-UDP-higher-packe…

…t-loss-compared-to-nuttcp

No select() when reading stream data

src/iperf_sctp.c

@@ -56,7 +56,7 @@ iperf_sctp_recv(struct iperf_stream *sp)
 #if defined(HAVE_SCTP_H)
     int r;
 
-    r = Nread(sp->socket, sp->buffer, sp->settings->blksize, Psctp);
+    r = Nread_no_select(sp->socket, sp->buffer, sp->settings->blksize, Psctp);
     if (r < 0)
         return r;
 

src/iperf_tcp.c

@@ -58,7 +58,7 @@ iperf_tcp_recv(struct iperf_stream *sp)
 {
     int r;
 
-    r = Nread(sp->socket, sp->buffer, sp->settings->blksize, Ptcp);
+    r = Nread_no_select(sp->socket, sp->buffer, sp->settings->blksize, Ptcp);
 
     if (r < 0)
         return r;

src/iperf_udp.c

@@ -62,7 +62,7 @@ iperf_udp_recv(struct iperf_stream *sp)
     double    transit = 0, d = 0;
     struct iperf_time sent_time, arrival_time, temp_time;
 
-    r = Nread(sp->socket, sp->buffer, size, Pudp);
+    r = Nread_no_select(sp->socket, sp->buffer, size, Pudp);
 
     /*
      * If we got an error in the read, or if we didn't read anything

src/net.c

@@ -452,6 +452,33 @@ Nread(int fd, char *buf, size_t count, int prot)
     return count - nleft;
 }
 
+/********************************************************************/
+/* reads 'count' bytes from a socket - but without using select()   */
+/********************************************************************/
+int
+Nread_no_select(int fd, char *buf, size_t count, int prot)
+{
+    register ssize_t r;
+    register size_t nleft = count;
+
+    while (nleft > 0) {
+        r = read(fd, buf, nleft);
+        if (r < 0) {
+            /* XXX EWOULDBLOCK can't happen without non-blocking sockets */
+            if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
+                break;
+            else
+                return NET_HARDERROR;
+        } else if (r == 0)
+            break;
+
+        nleft -= r;
+        buf += r;
+
+    }
+    return count - nleft;
+}
+
 
 /*
  *                      N W R I T E

src/net.h

@@ -32,6 +32,7 @@ int create_socket(int domain, int proto, const char *local, const char *bind_dev
 int netdial(int domain, int proto, const char *local, const char *bind_dev, int local_port, const char *server, int port, int timeout);
 int netannounce(int domain, int proto, const char *local, const char *bind_dev, int port);
 int Nread(int fd, char *buf, size_t count, int prot);
+int Nread_no_select(int fd, char *buf, size_t count, int prot);
 int Nwrite(int fd, const char *buf, size_t count, int prot) /* __attribute__((hot)) */;
 int has_sendfile(void);
 int Nsendfile(int fromfd, int tofd, const char *buf, size_t count) /* __attribute__((hot)) */;