Re: [libvirt] [PATCHv2] build: use gnulib passfd for simpler SCM_RIGHTS code

26 Apr 2011


      On 04/25/2011 10:21 AM, Eric Blake wrote:
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On 04/25/2011 01:17 AM, Laine Stump wrote:
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@@ -1529,26 +1513,20 @@ virFileOpenAs(const char *path, int openflags,
mode_t mode,
           VIR_FORCE_CLOSE(pair[1]);
do {
-            ret = recvmsg(pair[0],&msg, 0);
+            ret = recvfd(pair[0], 0);
           } while (ret<   0&&   errno == EINTR);
ret == -1 and errno == EACCES on failure to transfer fd...
...
...
-        if (ret<   0) {
+        if (ret<   0&&   errno != EACCES) {
               ret = -errno;
               VIR_FORCE_CLOSE(pair[0]);
               while ((waitret = waitpid(pid, NULL, 0) == -1)
                      &&   (errno == EINTR));
               goto parenterror;
+        } else {
+            fd = ret;
           }
so now fd == -1...
...
if (!WIFEXITED(status) || (ret = -WEXITSTATUS(status)) == -EACCES ||
             fd == -1) {
             /* fall back to the simpler method, which works better in
              * some cases */
             return virFileOpenAsNoFork(path, openflags, mode, uid, gid, flags);
         }
so this uses the fallback code, regardless of child exit status, and we
also ensured that the child got reaped.
...
What if errno == EACCES? Will we be getting all the error recovery we
need in the caller?
Yes.
Okay. In that case, ACK.

    