[platform process list] add a flag for showing the processes of all users

Summary:
For context: https://reviews.llvm.org/D68293

We need a way to show all the processes on android regardless of the user id.
When you run `platform process list`, you only see the processes with the same user as the user that launched lldb-server. However, it's quite useful to see all the processes, though, and it will lay a foundation for full apk debugging support from lldb.

Before:
```
PID    PARENT USER       TRIPLE                   NAME
====== ====== ========== ======================== ============================
3234   1                 aarch64-unknown-linux-android adbd
8034   3234              aarch64-unknown-linux-android sh
9096   3234              aarch64-unknown-linux-android sh
9098   9096              aarch64-unknown-linux-android lldb-server
(lldb) ^D
```

Now:
```
(lldb) platform process list -x
205 matching processes were found on "remote-android"
PID    PARENT USER       TRIPLE                   NAME
====== ====== ========== ======================== ============================
1      0                                          init
524    1                                          init
525    1                                          init
531    1                                          ueventd
568    1                                          logd
569    1                 aarch64-unknown-linux-android servicemanager
570    1                 aarch64-unknown-linux-android hwservicemanager
571    1                 aarch64-unknown-linux-android vndservicemanager
577    1                 aarch64-unknown-linux-android qseecomd
580    577               aarch64-unknown-linux-android qseecomd
...
23816  979                                        com.android.providers.calendar
24600  979                                        com.verizon.mips.services
27888  979                                        com.hualai
28043  2378                                       com.android.chrome:sandboxed_process0
31449  979                                        com.att.shm
31779  979                                        com.samsung.android.authfw
31846  979                                        com.samsung.android.server.iris
32014  979                                        com.samsung.android.MtpApplication
32045  979                                        com.samsung.InputEventApp
```

Reviewers: labath,xiaobai,aadsm,clayborg

Subscribers:

> llvm-svn: 374584

llvm-svn: 374631

2 files changed, 65 insertions, 2 deletions

diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py
new file mode 100644
index 00000000000..f85665a17e5
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py
@@ -0,0 +1,35 @@
+import lldb
+import binascii
+import os
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test.decorators import *
+from gdbclientutils import *
+
+
+class TestPlatformClient(GDBRemoteTestBase):
+
+    def test_process_list_with_all_users(self):
+        """Test connecting to a remote linux platform"""
+
+        class MyResponder(MockGDBServerResponder):
+            def qfProcessInfo(self, packet):
+                if "all_users:1" in packet:
+                    return "pid:10;ppid:1;uid:1;gid:1;euid:1;egid:1;name:" + binascii.hexlify("/a/test_process".encode()).decode() + ";"
+                else:
+                    return "E04"
+
+        self.server.responder = MyResponder()
+
+        self.runCmd("platform select remote-linux")
+
+        try:
+            self.runCmd("platform connect connect://localhost:%d" %
+                        self.server.port)
+            self.assertTrue(self.dbg.GetSelectedPlatform().IsConnected())
+            self.expect("platform process list -x",
+                        substrs=["1 matching process was found", "test_process"])
+            self.expect("platform process list",
+                        error=True,
+                        substrs=["error: no processes were found on the \"remote-linux\" platform"])
+        finally:
+            self.dbg.GetSelectedPlatform().DisconnectRemote()
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
index 621279a0a99..8237d1e0712 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
@@ -3,6 +3,8 @@ import os.path
 import threading
 import socket
 import lldb
+import binascii
+import traceback
 from lldbsuite.support import seven
 from lldbsuite.test.lldbtest import *
 from lldbsuite.test import lldbtest_config
@@ -160,9 +162,34 @@ class MockGDBServerResponder:
             return self.QListThreadsInStopReply()
         if packet.startswith("qMemoryRegionInfo:"):
             return self.qMemoryRegionInfo()
+        if packet == "qQueryGDBServer":
+            return self.qQueryGDBServer()
+        if packet == "qHostInfo":
+            return self.qHostInfo()
+        if packet == "qGetWorkingDir":
+            return self.qGetWorkingDir()
+        if packet == "qsProcessInfo":
+            return self.qsProcessInfo()
+        if packet.startswith("qfProcessInfo"):
+            return self.qfProcessInfo(packet)
 
         return self.other(packet)
 
+    def qsProcessInfo(self):
+        return "E04"
+
+    def qfProcessInfo(self, packet):
+        return "E04"
+
+    def qGetWorkingDir(self):
+        return "2f"
+
+    def qHostInfo(self):
+        return "ptrsize:8;endian:little;"
+
+    def qQueryGDBServer(self):
+        return "E04"
+
     def interrupt(self):
         raise self.UnexpectedPacketException()
 
@@ -171,7 +198,7 @@ class MockGDBServerResponder:
 
     def vCont(self, packet):
         raise self.UnexpectedPacketException()
-    
+
     def readRegisters(self):
         return "00000000" * self.registerCount
 
@@ -315,6 +342,8 @@ class MockGDBServer:
                     break
                 self._receive(data)
             except Exception as e:
+                print("An exception happened when receiving the response from the gdb server. Closing the client...")
+                traceback.print_exc()
                 self._client.close()
                 break
 
@@ -425,7 +454,6 @@ class MockGDBServer:
     class InvalidPacketException(Exception):
         pass
 
-
 class GDBRemoteTestBase(TestBase):
     """
     Base class for GDB client tests.