!1084 optimize ueventd service

Merge pull request !1084 from cheng_jinsong/permanentUeventd

services/etc/group

@@ -4,6 +4,7 @@ system:x:1000:
 radio:x:1001:
 bluetooth:x:1002:
 graphics:x:1003:
+ueventd:x:1004:root
 file_manager:x:1006:
 log:x:1007:
 user_data_rw:x:1008:

services/etc/passwd

@@ -4,6 +4,7 @@ system:x:1000:1000:::/bin/false
 radio:x:1001:1001:::/bin/false
 bluetooth:x:1002:1002:::/bin/false
 graphics:x:1003:1003:::/bin/false
+ueventd:x:1004:1004:::/bin/false
 file_manager:x:1006:1006:::/bin/false
 log:x:1007:1007:::/bin/false
 user_data_rw:x:1008:1008:::/bin/false

services/etc/ueventd.cfg

@@ -2,6 +2,8 @@
     "services" : [{
             "name" : "ueventd",
             "path" : ["/system/bin/ueventd"],
+            "uid" : "ueventd",
+            "gid" : ["ueventd"],
             "socket" : [{
                 "name" : "ueventd",
                 "family" : "AF_NETLINK",
@@ -17,6 +19,7 @@
                     "SOCK_NONBLOCK"
                 ]
             }],
+            "caps" : ["DAC_OVERRIDE", "MKNOD", "CHOWN", "FOWNER"],
             "critical" : [ 0, 15, 5],
             "ondemand" : true,
             "sandbox" : 0,

ueventd/ueventd_device_handler.c

@@ -89,11 +89,11 @@ static inline void AdjustDeviceNodePermissions(const char *deviceNode, uid_t uid
         return;
     }
     if (chown(deviceNode, uid, gid) != 0) {
-        INIT_LOGW("Failed to change \" %s \" owner", deviceNode);
+        INIT_LOGW("Failed to change \" %s \" owner, errno %d", deviceNode, errno);
     }
 
     if (chmod(deviceNode, mode) != 0) {
-        INIT_LOGW("Failed to change \" %s \" mode", deviceNode);
+        INIT_LOGW("Failed to change \" %s \" mode, errno %d", deviceNode, errno);
     }
 }
 

ueventd/ueventd_main.c

@@ -15,6 +15,7 @@
 
 #include <limits.h>
 #include <poll.h>
+#include <stdbool.h>
 #include "ueventd.h"
 #include "ueventd_read_cfg.h"
 #include "ueventd_socket.h"
@@ -22,16 +23,17 @@
 #include "init_log.h"
 #include "init_socket.h"
 
-static void PollUeventdSocketTimeout(int ueventSockFd)
+static void PollUeventdSocketTimeout(int ueventSockFd, bool ondemand)
 {
     struct pollfd pfd = {};
     pfd.events = POLLIN;
     pfd.fd = ueventSockFd;
+    int timeout = ondemand ? UEVENTD_POLL_TIME : -1;
     int ret = -1;
 
     while (1) {
         pfd.revents = 0;
-        ret = poll(&pfd, 1, UEVENTD_POLL_TIME);
+        ret = poll(&pfd, 1, timeout);
         if (ret == 0) {
             INIT_LOGI("poll ueventd socket timeout, ueventd exit");
             return;
@@ -54,10 +56,12 @@ int main(int argc, char **argv)
     while (ueventdConfigs[i] != NULL) {
         ParseUeventdConfigFile(ueventdConfigs[i++]);
     }
+    bool ondemand = true;
     int ueventSockFd = GetControlSocket("ueventd");
     if (ueventSockFd < 0) {
         INIT_LOGW("Failed to get uevent socket, try to create");
         ueventSockFd = UeventdSocketInit();
+        ondemand = false;
     }
     if (ueventSockFd < 0) {
         INIT_LOGE("Failed to create uevent socket!");
@@ -76,6 +80,6 @@ int main(int argc, char **argv)
         INIT_LOGI("ueventd start to process uevent message");
         ProcessUevent(ueventSockFd, NULL, 0); // Not require boot devices
     }
-    PollUeventdSocketTimeout(ueventSockFd);
+    PollUeventdSocketTimeout(ueventSockFd, ondemand);
     return 0;
 }