On 12/06/2010 05:44 AM, Jiri Denemark wrote:
free(virtTestLogContentAndReset()); cmd = virCommandNew(abs_builddir "/commandhelper-doesnotexist"); - if (virCommandRun(cmd, NULL) == 0) + if (!cmd || virCommandRun(cmd, NULL) == 0)
The API explicitly does *not* require you to check !cmd after virCommandNew. virCommandRun() and other APis will check that for you and return ENOMEM.
That was my suspicion too but then I looked at virCommandRun implementation and saw this:
if (!cmd || cmd->has_error == -1) { virCommandError(VIR_ERR_INTERNAL_ERROR, "%s", _("invalid use of command API")); return -1; } if (cmd->has_error == ENOMEM) { virReportOOMError(); return -1; }
That is, if virCommandNew() returns NULL for either reason, by running virCommandRun() on it, the original error (probably OOM) gets overwritten by an internal error.
Oh, I see. The correct fix is to swap that precedence in command.c (I'm working on a patch): if (!cmd || cmd->has_error == ENOMEM) { virReportOOMError(); return -1; } if (cmd->has_error) { report invalid use of command as internal error } Then you can safely ignore allocation failure on virCommandNew up until virCommandRun complains about the OOM failure, and it won't be treated as an internal usage error. -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org