From 131a18f68dc73f208bb76a944fc6d42c86cfad3b Mon Sep 17 00:00:00 2001
From: Laurent Bercot <ska-skaware@skarnet.org>
Date: Wed, 31 Dec 2014 16:27:44 +0000
Subject:  Safe wrappers around sendmsg and recvmsg in unixmessage primitives

---
 src/libunixonacid/unixmessage_receive.c      |  9 ++++++---
 src/libunixonacid/unixmessage_sender_flush.c | 11 +++++++++--
 2 files changed, 15 insertions(+), 5 deletions(-)

(limited to 'src')

diff --git a/src/libunixonacid/unixmessage_receive.c b/src/libunixonacid/unixmessage_receive.c
index d25195b..21491fa 100644
--- a/src/libunixonacid/unixmessage_receive.c
+++ b/src/libunixonacid/unixmessage_receive.c
@@ -49,7 +49,7 @@ static int unixmessage_receiver_fill (unixmessage_receiver_t *b)
     .msg_controllen = sizeof(ancilbuf)
   } ;
   unsigned int auxlen ;
-  int r ;
+  int r = -1 ;
   if (cbuffer_isfull(&b->mainb) || cbuffer_isfull(&b->auxb))
     return (errno = ENOBUFS, -1) ;
   {
@@ -57,8 +57,11 @@ static int unixmessage_receiver_fill (unixmessage_receiver_t *b)
     cbuffer_wpeek(&b->mainb, v) ;
     iovec_from_siovec(iov, v, 2) ;
   }
-  r = recvmsg(b->fd, &msghdr, awesomeflags) ;
-  if (r <= 0) return r ;
+  while (r < 0)
+  {
+    r = recvmsg(b->fd, &msghdr, awesomeflags) ;
+    if (!r || (r < 0 && errno != EINTR)) return r ;
+  }
   {
     struct cmsghdr *c = CMSG_FIRSTHDR(&msghdr) ;
     if (c)
diff --git a/src/libunixonacid/unixmessage_sender_flush.c b/src/libunixonacid/unixmessage_sender_flush.c
index a115c58..6a0a04b 100644
--- a/src/libunixonacid/unixmessage_sender_flush.c
+++ b/src/libunixonacid/unixmessage_sender_flush.c
@@ -9,6 +9,7 @@
 #include <sys/socket.h>
 #include <sys/uio.h>
 #include <unistd.h>
+#include <errno.h>
 #include <skalibs/uint.h>
 #include <skalibs/diuint.h>
 #include <skalibs/stralloc.h>
@@ -63,8 +64,14 @@ int unixmessage_sender_flush (unixmessage_sender_t *b)
         ((int *)CMSG_DATA(cp))[i] = fd < 0 ? -(fd+1) : fd ;
       }
     }
-    if (sendmsg(b->fd, &hdr, MSG_NOSIGNAL) < (int)(len + (sizeof(unsigned int) << 1)))
-      return -(int)(b->head-oldhead)-1 ;
+    for (;;)
+    {
+      register int r = sendmsg(b->fd, &hdr, MSG_NOSIGNAL) ;
+      if (r == -1 && errno == EINTR) continue ;
+      if (r < (int)(len + (sizeof(unsigned int) << 1)))
+        return -(int)(b->head-oldhead)-1 ;
+      break ;
+    }
 #ifndef SKALIBS_HASANCILAUTOCLOSE
     if (nfds)
     {
-- 
cgit v1.2.3