From 15dcc62c720be795acaeb647c65632af466729a5 Mon Sep 17 00:00:00 2001
From: Josh Gao <jmgao@google.com>
Date: Fri, 5 Oct 2018 17:09:41 -0700
Subject: [PATCH] adbd: clean up jdwp service a bit.

Change-Id: Ia42447576b047dfa9ddc0b73b87adc8114e3f20f
Test: ./test_device.py
---
 adb/daemon/jdwp_service.cpp | 100 +++++++++++++-----------------------
 1 file changed, 35 insertions(+), 65 deletions(-)

diff --git a/adb/daemon/jdwp_service.cpp b/adb/daemon/jdwp_service.cpp
index b40faee6f..fe79acd97 100644
--- a/adb/daemon/jdwp_service.cpp
+++ b/adb/daemon/jdwp_service.cpp
@@ -212,6 +212,7 @@ static size_t jdwp_process_list_msg(char* buffer, size_t bufferlen) {
 
 static void jdwp_process_event(int socket, unsigned events, void* _proc) {
     JdwpProcess* proc = reinterpret_cast<JdwpProcess*>(_proc);
+    CHECK_EQ(socket, proc->socket);
 
     if (events & FDE_READ) {
         if (proc->pid < 0) {
@@ -225,82 +226,50 @@ static void jdwp_process_event(int socket, unsigned events, void* _proc) {
             D("Adding pid %d to jdwp process list", proc->pid);
             jdwp_process_list_updated();
         } else {
-            /* the pid was read, if we get there it's probably because the connection
-             * was closed (e.g. the JDWP process exited or crashed) */
-            char buf[32];
-
-            while (true) {
-                int len = TEMP_FAILURE_RETRY(recv(socket, buf, sizeof(buf), 0));
-
-                if (len == 0) {
-                    D("terminating JDWP %d connection: EOF", proc->pid);
-                    break;
-                } else if (len < 0) {
-                    if (len < 0 && errno == EAGAIN) {
-                        return;
-                    }
-
-                    D("terminating JDWP %d connection: EOF", proc->pid);
-                    break;
-                } else {
-                    D("ignoring unexpected JDWP %d control socket activity (%d bytes)", proc->pid,
-                      len);
-                }
-            }
-
+            // We already have the PID, if we can read from the socket, we've probably hit EOF.
+            D("terminating JDWP connection %d", proc->pid);
             goto CloseProcess;
         }
     }
 
     if (events & FDE_WRITE) {
         D("trying to send fd to JDWP process (count = %zu)", proc->out_fds.size());
-        if (!proc->out_fds.empty()) {
-            int fd = proc->out_fds.back().get();
-            struct cmsghdr* cmsg;
-            struct msghdr msg;
-            struct iovec iov;
-            char dummy = '!';
-            char buffer[sizeof(struct cmsghdr) + sizeof(int)];
+        CHECK(!proc->out_fds.empty());
 
-            iov.iov_base = &dummy;
-            iov.iov_len = 1;
-            msg.msg_name = nullptr;
-            msg.msg_namelen = 0;
-            msg.msg_iov = &iov;
-            msg.msg_iovlen = 1;
-            msg.msg_flags = 0;
-            msg.msg_control = buffer;
-            msg.msg_controllen = sizeof(buffer);
+        int fd = proc->out_fds.back().get();
+        struct cmsghdr* cmsg;
+        struct msghdr msg;
+        struct iovec iov;
+        char dummy = '!';
+        char buffer[sizeof(struct cmsghdr) + sizeof(int)];
 
-            cmsg = CMSG_FIRSTHDR(&msg);
-            cmsg->cmsg_len = msg.msg_controllen;
-            cmsg->cmsg_level = SOL_SOCKET;
-            cmsg->cmsg_type = SCM_RIGHTS;
-            ((int*)CMSG_DATA(cmsg))[0] = fd;
+        iov.iov_base = &dummy;
+        iov.iov_len = 1;
+        msg.msg_name = nullptr;
+        msg.msg_namelen = 0;
+        msg.msg_iov = &iov;
+        msg.msg_iovlen = 1;
+        msg.msg_flags = 0;
+        msg.msg_control = buffer;
+        msg.msg_controllen = sizeof(buffer);
 
-            if (!set_file_block_mode(proc->socket, true)) {
-                VLOG(JDWP) << "failed to set blocking mode for fd " << proc->socket;
-                goto CloseProcess;
-            }
+        cmsg = CMSG_FIRSTHDR(&msg);
+        cmsg->cmsg_len = msg.msg_controllen;
+        cmsg->cmsg_level = SOL_SOCKET;
+        cmsg->cmsg_type = SCM_RIGHTS;
+        ((int*)CMSG_DATA(cmsg))[0] = fd;
 
-            int ret = TEMP_FAILURE_RETRY(sendmsg(proc->socket, &msg, 0));
-            if (ret < 0) {
-                D("sending new file descriptor to JDWP %d failed: %s", proc->pid, strerror(errno));
-                goto CloseProcess;
-            }
+        int ret = TEMP_FAILURE_RETRY(sendmsg(socket, &msg, 0));
+        if (ret < 0) {
+            D("sending new file descriptor to JDWP %d failed: %s", proc->pid, strerror(errno));
+            goto CloseProcess;
+        }
 
-            D("sent file descriptor %d to JDWP process %d", fd, proc->pid);
+        D("sent file descriptor %d to JDWP process %d", fd, proc->pid);
 
-            proc->out_fds.pop_back();
-
-            if (!set_file_block_mode(proc->socket, false)) {
-                VLOG(JDWP) << "failed to set non-blocking mode for fd " << proc->socket;
-                goto CloseProcess;
-            }
-
-            if (proc->out_fds.empty()) {
-                fdevent_del(proc->fde, FDE_WRITE);
-            }
+        proc->out_fds.pop_back();
+        if (proc->out_fds.empty()) {
+            fdevent_del(proc->fde, FDE_WRITE);
         }
     }
 
@@ -406,9 +375,10 @@ static int jdwp_control_init(JdwpControl* control, const char* sockname, int soc
     return 0;
 }
 
-static void jdwp_control_event(int s, unsigned events, void* _control) {
+static void jdwp_control_event(int fd, unsigned events, void* _control) {
     JdwpControl* control = (JdwpControl*)_control;
 
+    CHECK_EQ(fd, control->listen_socket);
     if (events & FDE_READ) {
         int s = adb_socket_accept(control->listen_socket, nullptr, nullptr);
         if (s < 0) {