adb: delete vestigial SHELL_EXIT_NOTIFY_FD.

There exists no path through which a value other than -1 can be written
to the SHELL_EXIT_NOTIFY_FD.

Bug: http://b/74616284
Test: adb_test
Test: adbd_test
Test: python test_device.py
Change-Id: I0630c302ba06bc76917f0445aea75d2dbe1dc865
(cherry picked from commit dcc055af64)

adb/adb.h

@@ -196,10 +196,6 @@ ConnectionState connection_state(atransport* t);
 
 extern const char* adb_device_banner;
 
-#if !ADB_HOST
-extern int SHELL_EXIT_NOTIFY_FD;
-#endif  // !ADB_HOST
-
 #define CHUNK_SIZE (64 * 1024)
 
 #if !ADB_HOST

adb/fdevent.cpp

@@ -42,13 +42,6 @@
 #include "adb_unique_fd.h"
 #include "adb_utils.h"
 
-#if !ADB_HOST
-// This socket is used when a subproc shell service exists.
-// It wakes up the fdevent_loop() and cause the correct handling
-// of the shell's pseudo-tty master. I.e. force close it.
-int SHELL_EXIT_NOTIFY_FD = -1;
-#endif // !ADB_HOST
-
 #define FDE_EVENTMASK  0x00ff
 #define FDE_STATEMASK  0xff00
 
@@ -294,72 +287,6 @@ static void fdevent_call_fdfunc(fdevent* fde) {
     fde->func(fde->fd, events, fde->arg);
 }
 
-#if !ADB_HOST
-
-#include <sys/ioctl.h>
-
-static void fdevent_subproc_event_func(int fd, unsigned ev, void* /* userdata */) {
-    D("subproc handling on fd = %d, ev = %x", fd, ev);
-
-    CHECK_GE(fd, 0);
-
-    if (ev & FDE_READ) {
-        int subproc_fd;
-
-        if(!ReadFdExactly(fd, &subproc_fd, sizeof(subproc_fd))) {
-            LOG(FATAL) << "Failed to read the subproc's fd from " << fd;
-        }
-        auto it = g_poll_node_map.find(subproc_fd);
-        if (it == g_poll_node_map.end()) {
-            D("subproc_fd %d cleared from fd_table", subproc_fd);
-            adb_close(subproc_fd);
-            return;
-        }
-        fdevent* subproc_fde = it->second.fde;
-        if(subproc_fde->fd != subproc_fd) {
-            // Already reallocated?
-            LOG(FATAL) << "subproc_fd(" << subproc_fd << ") != subproc_fde->fd(" << subproc_fde->fd
-                       << ")";
-            return;
-        }
-
-        subproc_fde->force_eof = 1;
-
-        int rcount = 0;
-        ioctl(subproc_fd, FIONREAD, &rcount);
-        D("subproc with fd %d has rcount=%d, err=%d", subproc_fd, rcount, errno);
-        if (rcount != 0) {
-            // If there is data left, it will show up in the select().
-            // This works because there is no other thread reading that
-            // data when in this fd_func().
-            return;
-        }
-
-        D("subproc_fde %s", dump_fde(subproc_fde).c_str());
-        subproc_fde->events |= FDE_READ;
-        if(subproc_fde->state & FDE_PENDING) {
-            return;
-        }
-        subproc_fde->state |= FDE_PENDING;
-        fdevent_call_fdfunc(subproc_fde);
-    }
-}
-
-static void fdevent_subproc_setup() {
-    int s[2];
-
-    if(adb_socketpair(s)) {
-        PLOG(FATAL) << "cannot create shell-exit socket-pair";
-    }
-    D("fdevent_subproc: socket pair (%d, %d)", s[0], s[1]);
-
-    SHELL_EXIT_NOTIFY_FD = s[0];
-    fdevent *fde = fdevent_create(s[1], fdevent_subproc_event_func, NULL);
-    CHECK(fde != nullptr) << "cannot create fdevent for shell-exit handler";
-    fdevent_add(fde, FDE_READ);
-}
-#endif // !ADB_HOST
-
 static void fdevent_run_flush() EXCLUDES(run_queue_mutex) {
     // We need to be careful around reentrancy here, since a function we call can queue up another
     // function.
@@ -433,9 +360,6 @@ void fdevent_run_on_main_thread(std::function<void()> fn) {
 
 void fdevent_loop() {
     set_main_thread();
-#if !ADB_HOST
-    fdevent_subproc_setup();
-#endif // !ADB_HOST
     fdevent_run_setup();
 
     while (true) {

adb/fdevent_test.h

@@ -52,13 +52,8 @@ class FdeventTest : public ::testing::Test {
     }
 
     size_t GetAdditionalLocalSocketCount() {
-#if ADB_HOST
         // dummy socket installed in PrepareThread() + fdevent_run_on_main_thread socket
         return 2;
-#else
-        // dummy socket + fdevent_run_on_main_thread + fdevent_subproc_setup() sockets
-        return 3;
-#endif
     }
 
     void TerminateThread(std::thread& thread) {

adb/shell_service.cpp

@@ -681,22 +681,6 @@ void Subprocess::WaitForExit() {
         }
         protocol_sfd_.reset(-1);
     }
-
-    // Pass the local socket FD to the shell cleanup fdevent.
-    if (SHELL_EXIT_NOTIFY_FD >= 0) {
-        int fd = local_socket_sfd_;
-        if (WriteFdExactly(SHELL_EXIT_NOTIFY_FD, &fd, sizeof(fd))) {
-            D("passed fd %d to SHELL_EXIT_NOTIFY_FD (%d) for pid %d",
-              fd, SHELL_EXIT_NOTIFY_FD, pid_);
-            // The shell exit fdevent now owns the FD and will close it once
-            // the last bit of data flushes through.
-            static_cast<void>(local_socket_sfd_.release());
-        } else {
-            PLOG(ERROR) << "failed to write fd " << fd
-                        << " to SHELL_EXIT_NOTIFY_FD (" << SHELL_EXIT_NOTIFY_FD
-                        << ") for pid " << pid_;
-        }
-    }
 }
 
 }  // namespace

adb/shell_service_test.cpp

@@ -55,40 +55,20 @@ class ShellServiceTest : public ::testing::Test {
     static sighandler_t saved_sigpipe_handler_;
 
     int subprocess_fd_ = -1;
-    int shell_exit_receiver_fd_ = -1, saved_shell_exit_fd_;
 };
 
 sighandler_t ShellServiceTest::saved_sigpipe_handler_ = nullptr;
 
 void ShellServiceTest::StartTestSubprocess(
         const char* command, SubprocessType type, SubprocessProtocol protocol) {
-    // We want to intercept the shell exit message to make sure it's sent.
-    saved_shell_exit_fd_ = SHELL_EXIT_NOTIFY_FD;
-    int fd[2];
-    ASSERT_TRUE(adb_socketpair(fd) >= 0);
-    SHELL_EXIT_NOTIFY_FD = fd[0];
-    shell_exit_receiver_fd_ = fd[1];
-
     subprocess_fd_ = StartSubprocess(command, nullptr, type, protocol);
     ASSERT_TRUE(subprocess_fd_ >= 0);
 }
 
 void ShellServiceTest::CleanupTestSubprocess() {
     if (subprocess_fd_ >= 0) {
-        // Subprocess should send its FD to SHELL_EXIT_NOTIFY_FD for cleanup.
-        int notified_fd = -1;
-        ASSERT_TRUE(ReadFdExactly(shell_exit_receiver_fd_, &notified_fd,
-                                  sizeof(notified_fd)));
-        ASSERT_EQ(notified_fd, subprocess_fd_);
-
         adb_close(subprocess_fd_);
         subprocess_fd_ = -1;
-
-        // Restore SHELL_EXIT_NOTIFY_FD.
-        adb_close(SHELL_EXIT_NOTIFY_FD);
-        adb_close(shell_exit_receiver_fd_);
-        shell_exit_receiver_fd_ = -1;
-        SHELL_EXIT_NOTIFY_FD = saved_shell_exit_fd_;
     }
 }