On Mon, Jun 06, 2016 at 15:16:50 +0100, Daniel Berrange wrote:
The sd_notify method is used to tell systemd when libvirtd has finished starting up. All it does is send a datagram containing the string parameter to systemd on a UNIX socket named in the NOTIFY_SOCKET environment variable. Rather than pulling in the systemd libraries for this, just code the notification directly in libvirt as this is a stable ABI from systemd's POV which explicitly allows independant implementations:
See "Reimplementable Independently" column in the "$NOTIFY_SOCKET Daemon Notifications" row:
https://www.freedesktop.org/wiki/Software/systemd/InterfacePortabilityAndSta...
Signed-off-by: Daniel P. Berrange <berrange@redhat.com> --- configure.ac | 2 -- libvirt.spec.in | 12 ----------- m4/virt-systemd-daemon.m4 | 34 ------------------------------- src/Makefile.am | 4 ++-- src/util/virsystemd.c | 52 ++++++++++++++++++++++++++++++++++++++++++----- 5 files changed, 49 insertions(+), 55 deletions(-) delete mode 100644 m4/virt-systemd-daemon.m4
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diff --git a/src/util/virsystemd.c b/src/util/virsystemd.c index 4883f94..71b8f33 100644 --- a/src/util/virsystemd.c +++ b/src/util/virsystemd.c
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@@ -480,9 +482,49 @@ int virSystemdTerminateMachine(const char *name) void virSystemdNotifyStartup(void) { -#ifdef WITH_SYSTEMD_DAEMON - sd_notify(0, "READY=1"); -#endif +#ifdef HAVE_SYS_UN_H + const char *path; + const char *msg = "READY=1"; + int fd; + struct sockaddr_un un = { + .sun_family = AF_UNIX, + }; + struct iovec iov = { + .iov_base = (char *)msg, + .iov_len = strlen(msg), + }; + struct msghdr mh = { + .msg_name = &un, + .msg_namelen = sizeof(un), + .msg_iov = &iov, + .msg_iovlen = 1, + }; + + if (!(path = virGetEnvBlockSUID("NOTIFY_SOCKET"))) { + VIR_DEBUG("Skipping systemd notify, not requested"); + return; + } + + if (strlen(path) > sizeof(un.sun_path)) {
Off-by-one by not considering the trailing \0
+ VIR_WARN("Systemd notify socket path '%s' too long", path); + return; + }
ACK