Re: [Spice-devel] [vdagent] Make sure the child is able to connect to the X server before exiting the mainline.
On 06/24/2014 12:05 AM, Jeremy White wrote:
This allows the vdagent to be used in the Xsetup phase of an xdm session;
otherwise, its X11 connection fails because of the greeter display grab.
relies on the fact the socketpair fd's are never 0 (i.e. fd[1] below is
never 0). Which I think is wrong, but only if you close the default fd
0, which you won't, so fine by me.
ACK.
Signed-off-by: Jeremy White jwh...@codeweavers.com
---
src/vdagent.c | 50 --
1 file changed, 44 insertions(+), 6 deletions(-)
diff --git a/src/vdagent.c b/src/vdagent.c
index d7f7aba..905ff5b 100644
--- a/src/vdagent.c
+++ b/src/vdagent.c
@@ -35,6 +35,7 @@
#include sys/stat.h
#include spice/vd_agent.h
#include glib.h
+#include poll.h
#include udscs.h
#include vdagentd-proto.h
@@ -151,9 +152,34 @@ static void quit_handler(int sig)
quit = 1;
}
-void daemonize(void)
+/* When we daemonize, it is useful to have the main process
+ wait to make sure the X connection worked. We wait up
+ to 10 seconds to get an 'all clear' from the child
+ before we exit. If we don't, we're able to exit with a
+ status that indicates an error occured */
+void wait_and_exit(int s)
{
-int x, retval = 0;
+char buf[4];
+struct pollfd p;
+p.fd = s;
+p.events = POLLIN;
+
+if (poll(p, 1, 1) 0)
+if (read(s, buf, sizeof(buf)) 0)
+exit(0);
+
+exit(1);
+}
+
+int daemonize(void)
+{
+int x;
+int fd[2];
+
+if (socketpair(PF_LOCAL, SOCK_STREAM, 0, fd)) {
+syslog(LOG_ERR, socketpair : %s, strerror(errno));
+exit(1);
+}
/* detach from terminal */
switch (fork()) {
@@ -161,13 +187,17 @@ void daemonize(void)
close(0); close(1); close(2);
setsid();
x = open(/dev/null, O_RDWR); x = dup(x); x = dup(x);
-break;
+close(fd[0]);
+return fd[1];
case -1:
syslog(LOG_ERR, fork: %s, strerror(errno));
-retval = 1;
+exit(1);
default:
-exit(retval);
+close(fd[1]);
+wait_and_exit(fd[0]);
}
+
+return 0;
}
static int file_test(const char *path)
@@ -182,6 +212,7 @@ int main(int argc, char *argv[])
fd_set readfds, writefds;
int c, n, nfds, x11_fd;
int do_daemonize = 1;
+int parent_socket = 0;
int x11_sync = 0;
struct sigaction act;
@@ -236,7 +267,7 @@ int main(int argc, char *argv[])
}
if (do_daemonize)
-daemonize();
+parent_socket = daemonize();
reconnect:
if (version_mismatch) {
@@ -275,6 +306,13 @@ reconnect:
vdagent_file_xfers = vdagent_file_xfers_create(client, fx_dir,
fx_open_dir, debug);
+if (parent_socket) {
+if (write(parent_socket, OK, 2) != 2)
+syslog(LOG_WARNING, Parent already gone.);
+close(parent_socket);
+parent_socket = 0;
+}
+
while (client !quit) {
FD_ZERO(readfds);
FD_ZERO(writefds);
___
Spice-devel mailing list
Spice-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/spice-devel
Re: [Spice-devel] [vdagent] Make sure the child is able to connect to the X server before exiting the mainline.
On 06/24/2014 12:05 AM, Jeremy White wrote:
This allows the vdagent to be used in the Xsetup phase of an xdm session;
otherwise, its X11 connection fails because of the greeter display grab.
But could you make the comment contain the discussion where you
explained this in more detail?
Signed-off-by: Jeremy White jwh...@codeweavers.com
---
src/vdagent.c | 50 --
1 file changed, 44 insertions(+), 6 deletions(-)
diff --git a/src/vdagent.c b/src/vdagent.c
index d7f7aba..905ff5b 100644
--- a/src/vdagent.c
+++ b/src/vdagent.c
@@ -35,6 +35,7 @@
#include sys/stat.h
#include spice/vd_agent.h
#include glib.h
+#include poll.h
#include udscs.h
#include vdagentd-proto.h
@@ -151,9 +152,34 @@ static void quit_handler(int sig)
quit = 1;
}
-void daemonize(void)
+/* When we daemonize, it is useful to have the main process
+ wait to make sure the X connection worked. We wait up
+ to 10 seconds to get an 'all clear' from the child
+ before we exit. If we don't, we're able to exit with a
+ status that indicates an error occured */
+void wait_and_exit(int s)
{
-int x, retval = 0;
+char buf[4];
+struct pollfd p;
+p.fd = s;
+p.events = POLLIN;
+
+if (poll(p, 1, 1) 0)
+if (read(s, buf, sizeof(buf)) 0)
+exit(0);
+
+exit(1);
+}
+
+int daemonize(void)
+{
+int x;
+int fd[2];
+
+if (socketpair(PF_LOCAL, SOCK_STREAM, 0, fd)) {
+syslog(LOG_ERR, socketpair : %s, strerror(errno));
+exit(1);
+}
/* detach from terminal */
switch (fork()) {
@@ -161,13 +187,17 @@ void daemonize(void)
close(0); close(1); close(2);
setsid();
x = open(/dev/null, O_RDWR); x = dup(x); x = dup(x);
-break;
+close(fd[0]);
+return fd[1];
case -1:
syslog(LOG_ERR, fork: %s, strerror(errno));
-retval = 1;
+exit(1);
default:
-exit(retval);
+close(fd[1]);
+wait_and_exit(fd[0]);
}
+
+return 0;
}
static int file_test(const char *path)
@@ -182,6 +212,7 @@ int main(int argc, char *argv[])
fd_set readfds, writefds;
int c, n, nfds, x11_fd;
int do_daemonize = 1;
+int parent_socket = 0;
int x11_sync = 0;
struct sigaction act;
@@ -236,7 +267,7 @@ int main(int argc, char *argv[])
}
if (do_daemonize)
-daemonize();
+parent_socket = daemonize();
reconnect:
if (version_mismatch) {
@@ -275,6 +306,13 @@ reconnect:
vdagent_file_xfers = vdagent_file_xfers_create(client, fx_dir,
fx_open_dir, debug);
+if (parent_socket) {
+if (write(parent_socket, OK, 2) != 2)
+syslog(LOG_WARNING, Parent already gone.);
+close(parent_socket);
+parent_socket = 0;
+}
+
while (client !quit) {
FD_ZERO(readfds);
FD_ZERO(writefds);
___
Spice-devel mailing list
Spice-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/spice-devel
