cmd/ld: retry short writes, to get error detail

Fixes #3802.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7228066

diff --git a/src/cmd/ld/lib.c b/src/cmd/ld/lib.c
index 152cd052c599bf3cb1e5ce66860ea44faffb7179..2c59fb8de20a20bca8ecee746ed16e93d99e9cf3 100644 (file)
--- a/src/cmd/ld/lib.c
+++ b/src/cmd/ld/lib.c
@@ -1447,6 +1447,23 @@ Yconv(Fmt *fp)
 
 vlong coutpos;
 
+static void
+dowrite(int fd, char *p, int n)
+{
+       int m;
+       
+       while(n > 0) {
+               m = write(fd, p, n);
+               if(m <= 0) {
+                       cursym = S;
+                       diag("write error: %r");
+                       errorexit();
+               }
+               n -= m;
+               p += m;
+       }
+}
+
 void
 cflush(void)
 {
@@ -1455,13 +1472,8 @@ cflush(void)
        if(cbpmax < cbp)
                cbpmax = cbp;
        n = cbpmax - buf.cbuf;
-       if(n) {
-               if(write(cout, buf.cbuf, n) != n) {
-                       diag("write error: %r");
-                       errorexit();
-               }
-               coutpos += n;
-       }
+       dowrite(cout, buf.cbuf, n);
+       coutpos += n;
        cbp = buf.cbuf;
        cbc = sizeof(buf.cbuf);
        cbpmax = cbp;
@@ -1502,10 +1514,7 @@ cwrite(void *buf, int n)
        cflush();
        if(n <= 0)
                return;
-       if(write(cout, buf, n) != n) {
-               diag("write error: %r");
-               errorexit();
-       }
+       dowrite(cout, buf, n);
        coutpos += n;
 }