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Diffstat (limited to 'erts/emulator/sys/unix/sys_drivers.c')
-rw-r--r--erts/emulator/sys/unix/sys_drivers.c76
1 files changed, 46 insertions, 30 deletions
diff --git a/erts/emulator/sys/unix/sys_drivers.c b/erts/emulator/sys/unix/sys_drivers.c
index 82096e5779..dc1c00ff96 100644
--- a/erts/emulator/sys/unix/sys_drivers.c
+++ b/erts/emulator/sys/unix/sys_drivers.c
@@ -1761,37 +1761,59 @@ static void forker_ready_input(ErlDrvData e, ErlDrvEvent fd)
erl_exit(ERTS_DUMP_EXIT, "erl_child_setup closed\n");
ASSERT(res == sizeof(*proto));
- ASSERT(proto->action == ErtsSysForkerProtoAction_SigChld);
-
- /* ideally this would be a port_command call, but as command is
- already used by the spawn_driver, we use control instead.
- Note that when using erl_drv_port_control it is an asynchronous
- control. */
- erl_drv_port_control(proto->u.sigchld.port_id, 'S',
- (char*)proto, sizeof(*proto));
-
-}
-static void forker_ready_output(ErlDrvData e, ErlDrvEvent fd)
-{
- ErlDrvPort port_num = (ErlDrvPort)e;
-
- while(driver_sizeq(port_num) > 0) {
+ if (proto->action == ErtsSysForkerProtoAction_StartAck) {
+ /* Ideally we would like to not have to ack each Start
+ command being sent over the uds, but it would seem
+ that some operating systems (only observed on FreeBSD)
+ throw away data on the uds when the socket becomes full,
+ so we have to.
+
+ Also the freebsd manual explicitly states that
+ you should not close fds before they are known
+ to have reached the other side, so this Ack protects
+ against that as well.
+ */
+ ErlDrvPort port_num = (ErlDrvPort)e;
int vlen;
SysIOVec *iov = driver_peekq(port_num, &vlen);
ErtsSysForkerProto *proto = (ErtsSysForkerProto *)iov[0].iov_base;
- ASSERT(iov[0].iov_len >= (sizeof(*proto)));
- if (sys_uds_write(forker_fd, (char*)proto, sizeof(*proto),
- proto->u.start.fds, 3, 0) < 0) {
- if (errno == ERRNO_BLOCK)
- return;
- erl_exit(ERTS_DUMP_EXIT, "Failed to write to erl_child_setup: %d\n", errno);
- }
+
close(proto->u.start.fds[0]);
close(proto->u.start.fds[1]);
if (proto->u.start.fds[1] != proto->u.start.fds[2])
close(proto->u.start.fds[2]);
+
driver_deq(port_num, sizeof(*proto));
+
+ if (driver_sizeq(port_num) > 0)
+ driver_select(port_num, forker_fd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ } else {
+ ASSERT(proto->action == ErtsSysForkerProtoAction_SigChld);
+
+ /* ideally this would be a port_command call, but as command is
+ already used by the spawn_driver, we use control instead.
+ Note that when using erl_drv_port_control it is an asynchronous
+ control. */
+ erl_drv_port_control(proto->u.sigchld.port_id, 'S',
+ (char*)proto, sizeof(*proto));
+ }
+
+}
+
+static void forker_ready_output(ErlDrvData e, ErlDrvEvent fd)
+{
+ ErlDrvPort port_num = (ErlDrvPort)e;
+
+ int vlen;
+ SysIOVec *iov = driver_peekq(port_num, &vlen);
+ ErtsSysForkerProto *proto = (ErtsSysForkerProto *)iov[0].iov_base;
+ ASSERT(iov[0].iov_len >= (sizeof(*proto)));
+ if (sys_uds_write(forker_fd, (char*)proto, sizeof(*proto),
+ proto->u.start.fds, 3, 0) < 0) {
+ if (errno == ERRNO_BLOCK)
+ return;
+ erl_exit(ERTS_DUMP_EXIT, "Failed to write to erl_child_setup uds: %d", errno);
}
driver_select(port_num, forker_fd, ERL_DRV_WRITE, 0);
@@ -1804,25 +1826,19 @@ static ErlDrvSSizeT forker_control(ErlDrvData e, unsigned int cmd, char *buf,
ErlDrvPort port_num = (ErlDrvPort)e;
int res;
- if (driver_sizeq(port_num) > 0) {
- driver_enq(port_num, buf, len);
+ driver_enq(port_num, buf, len);
+ if (driver_sizeq(port_num) > sizeof(*proto)) {
return 0;
}
if ((res = sys_uds_write(forker_fd, (char*)proto, sizeof(*proto),
proto->u.start.fds, 3, 0)) < 0) {
if (errno == ERRNO_BLOCK) {
- driver_enq(port_num, buf, len);
driver_select(port_num, forker_fd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
return 0;
}
erl_exit(ERTS_DUMP_EXIT, "Failed to write to erl_child_setup: %d\n", errno);
}
- ASSERT(res == sizeof(*proto));
- close(proto->u.start.fds[0]);
- close(proto->u.start.fds[1]);
- if (proto->u.start.fds[1] != proto->u.start.fds[2])
- close(proto->u.start.fds[2]);
return 0;
}