logd: add EXIT command

Debugging aid. Allows us to run:

$ cat -n '<STUFF>\0EXIT\0' | nc -U /dev/socket/logd

and the pipeline will exit once done. Without the EXIT command
we will have to <CTRL+C> out to terminate the pipeline. This is
necessary since Android's netcat command does not support the -q
feature, and having the EXIT command is faster and cleaner anyways.

Test: manual as noted above.
Bug: 31456426
Change-Id: I65333358188db85e2eb1bb6a14deed1565826ac4

2 files changed, 46 insertions, 14 deletions

diff --git a/logd/CommandListener.cpp b/logd/CommandListener.cpp
index 7394f1140..52c67424a 100644
--- a/logd/CommandListener.cpp
+++ b/logd/CommandListener.cpp
@@ -48,6 +48,7 @@ CommandListener::CommandListener(LogBuffer *buf, LogReader * /*reader*/,
     registerCmd(new SetPruneListCmd(buf));
     registerCmd(new GetPruneListCmd(buf));
     registerCmd(new ReinitCmd());
+    registerCmd(new ExitCmd(this));
 }
 
 CommandListener::ShutdownCmd::ShutdownCmd(LogReader *reader,
@@ -297,6 +298,21 @@ int CommandListener::ReinitCmd::runCommand(SocketClient *cli,
     return 0;
 }
 
+CommandListener::ExitCmd::ExitCmd(CommandListener *parent) :
+        LogCommand("EXIT"),
+        mParent(*parent) {
+}
+
+int CommandListener::ExitCmd::runCommand(SocketClient * cli,
+                                         int /*argc*/, char ** /*argv*/) {
+    setname();
+
+    cli->sendMsg("success");
+    release(cli);
+
+    return 0;
+}
+
 int CommandListener::getLogSocket() {
     static const char socketName[] = "logd";
     int sock = android_get_control_socket(socketName);
diff --git a/logd/CommandListener.h b/logd/CommandListener.h
index cbcd601a3..5d5017785 100644
--- a/logd/CommandListener.h
+++ b/logd/CommandListener.h
@@ -52,22 +52,38 @@ private:
         explicit name##Cmd(LogBuffer *buf);                      \
         virtual ~name##Cmd() {}                                  \
         int runCommand(SocketClient *c, int argc, char ** argv); \
-    };
+    }
 
-    LogBufferCmd(Clear)
-    LogBufferCmd(GetBufSize)
-    LogBufferCmd(SetBufSize)
-    LogBufferCmd(GetBufSizeUsed)
-    LogBufferCmd(GetStatistics)
-    LogBufferCmd(GetPruneList)
-    LogBufferCmd(SetPruneList)
+    LogBufferCmd(Clear);
+    LogBufferCmd(GetBufSize);
+    LogBufferCmd(SetBufSize);
+    LogBufferCmd(GetBufSizeUsed);
+    LogBufferCmd(GetStatistics);
+    LogBufferCmd(GetPruneList);
+    LogBufferCmd(SetPruneList);
 
-    class ReinitCmd : public LogCommand {
-    public:
-        ReinitCmd();
-        virtual ~ReinitCmd() {}
-        int runCommand(SocketClient *c, int argc, char ** argv);
-    };
+#define LogCmd(name)                                             \
+    class name##Cmd : public LogCommand {                        \
+    public:                                                      \
+        name##Cmd();                                             \
+        virtual ~name##Cmd() {}                                  \
+        int runCommand(SocketClient *c, int argc, char ** argv); \
+    }
+
+    LogCmd(Reinit);
+
+#define LogParentCmd(name)                                       \
+    class name##Cmd : public LogCommand {                        \
+        CommandListener &mParent;                                \
+    public:                                                      \
+        name##Cmd();                                             \
+        explicit name##Cmd(CommandListener *parent);             \
+        virtual ~name##Cmd() {}                                  \
+        int runCommand(SocketClient *c, int argc, char ** argv); \
+        void release(SocketClient *c) { mParent.release(c); }    \
+    }
+
+    LogParentCmd(Exit);
 
 };