From f366b3698b409405e1ee88476d1186f29fe14b06 Mon Sep 17 00:00:00 2001
From: Benoit Goby <benoit@android.com>
Date: Fri, 16 Mar 2012 14:50:07 -0700
Subject: [PATCH] adb: Don't synchronize with transport using sleep

Services that cause adbd to reboot are currently implemented this way:
    write(fd, response)
    close(fd)
    sleep(1)
    exit(1)
sleep(1) is necessary to leave time for the transport to transmit
the response before the daemon exits. This is slow and unreliable.
Instead, add a flag to the asocket to make it exit the daemon only
after the socket is closed.

Change-Id: I9df45ea6221f0d9b828703b9b2316a5d4fe59352
---
 adb/adb.h      |  5 +++++
 adb/services.c | 13 -------------
 adb/sockets.c  | 14 ++++++++++++++
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/adb/adb.h b/adb/adb.h
index 85922bf80..03a7393a0 100644
--- a/adb/adb.h
+++ b/adb/adb.h
@@ -86,6 +86,11 @@ struct asocket {
         */
     int    closing;
 
+        /* flag: quit adbd when both ends close the
+        ** local service socket
+        */
+    int    exit_on_close;
+
         /* the asocket we are connected to
         */
 
diff --git a/adb/services.c b/adb/services.c
index 6bbd6f882..495a0830f 100644
--- a/adb/services.c
+++ b/adb/services.c
@@ -129,10 +129,6 @@ void restart_root_service(int fd, void *cookie)
         snprintf(buf, sizeof(buf), "restarting adbd as root\n");
         writex(fd, buf, strlen(buf));
         adb_close(fd);
-
-        // quit, and init will restart us as root
-        sleep(1);
-        exit(1);
     }
 }
 
@@ -154,10 +150,6 @@ void restart_tcp_service(int fd, void *cookie)
     snprintf(buf, sizeof(buf), "restarting in TCP mode port: %d\n", port);
     writex(fd, buf, strlen(buf));
     adb_close(fd);
-
-    // quit, and init will restart us in TCP mode
-    sleep(1);
-    exit(1);
 }
 
 void restart_usb_service(int fd, void *cookie)
@@ -168,10 +160,6 @@ void restart_usb_service(int fd, void *cookie)
     snprintf(buf, sizeof(buf), "restarting in USB mode\n");
     writex(fd, buf, strlen(buf));
     adb_close(fd);
-
-    // quit, and init will restart us in USB mode
-    sleep(1);
-    exit(1);
 }
 
 void reboot_service(int fd, void *arg)
@@ -371,7 +359,6 @@ static void subproc_waiter_service(int fd, void *cookie)
                 break;
             }
          }
-        usleep(100000);  // poll every 0.1 sec
     }
     D("shell exited fd=%d of pid=%d err=%d\n", fd, pid, errno);
     if (SHELL_EXIT_NOTIFY_FD >=0) {
diff --git a/adb/sockets.c b/adb/sockets.c
index df223b133..ce3c65ef4 100644
--- a/adb/sockets.c
+++ b/adb/sockets.c
@@ -199,6 +199,8 @@ static void local_socket_close(asocket *s)
 static void local_socket_destroy(asocket  *s)
 {
     apacket *p, *n;
+    int exit_on_close = s->exit_on_close;
+
     D("LS(%d): destroying fde.fd=%d\n", s->id, s->fde.fd);
 
         /* IMPORTANT: the remove closes the fd
@@ -214,6 +216,11 @@ static void local_socket_destroy(asocket  *s)
     }
     remove_socket(s);
     free(s);
+
+    if (exit_on_close) {
+        D("local_socket_destroy: exiting\n");
+        exit(1);
+    }
 }
 
 
@@ -418,6 +425,13 @@ asocket *create_local_service_socket(const char *name)
 
     s = create_local_socket(fd);
     D("LS(%d): bound to '%s' via %d\n", s->id, name, fd);
+
+    if (!strcmp(name, "root:") || !strcmp(name, "usb:") ||
+                                  !strcmp(name, "tcpip:")) {
+        D("LS(%d): enabling exit_on_close\n", s->id);
+        s->exit_on_close = 1;
+    }
+
     return s;
 }