Merge changes Ibfa5e7e6,I706b57a9,I53d21134,I69d4d585
am: 9674bcbd23

Change-Id: Ibfec0e2581ec6ec6167d63e05deeed1263f0f458
diff --git a/adb/client/commandline.cpp b/adb/client/commandline.cpp
index c41db24..d6ce1a4 100644
--- a/adb/client/commandline.cpp
+++ b/adb/client/commandline.cpp
@@ -1795,6 +1795,11 @@
     }
     else if (!strcmp(argv[0], "track-devices")) {
         return adb_connect_command("host:track-devices");
+    } else if (!strcmp(argv[0], "raw")) {
+        if (argc != 2) {
+            return syntax_error("adb raw SERVICE");
+        }
+        return adb_connect_command(argv[1]);
     }
 
 
diff --git a/adb/fdevent.cpp b/adb/fdevent.cpp
index 1b7758c..f98c11a 100644
--- a/adb/fdevent.cpp
+++ b/adb/fdevent.cpp
@@ -21,6 +21,7 @@
 #include "fdevent.h"
 
 #include <fcntl.h>
+#include <inttypes.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
@@ -34,6 +35,7 @@
 #include <unordered_map>
 #include <vector>
 
+#include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/thread_annotations.h>
@@ -75,6 +77,8 @@
 static bool main_thread_valid;
 static uint64_t main_thread_id;
 
+static uint64_t fdevent_id;
+
 static bool run_needs_flush = false;
 static auto& run_queue_notify_fd = *new unique_fd();
 static auto& run_queue_mutex = *new std::mutex();
@@ -111,7 +115,8 @@
     if (fde->state & FDE_ERROR) {
         state += "E";
     }
-    return android::base::StringPrintf("(fdevent %d %s)", fde->fd.get(), state.c_str());
+    return android::base::StringPrintf("(fdevent %" PRIu64 ": fd %d %s)", fde->id, fde->fd.get(),
+                                       state.c_str());
 }
 
 void fdevent_install(fdevent* fde, int fd, fd_func func, void* arg) {
@@ -125,6 +130,7 @@
     CHECK_GE(fd, 0);
 
     fdevent* fde = new fdevent();
+    fde->id = fdevent_id++;
     fde->state = FDE_ACTIVE;
     fde->fd.reset(fd);
     fde->func = func;
@@ -352,10 +358,56 @@
     }
 }
 
+static void fdevent_check_spin(uint64_t cycle) {
+    // Check to see if we're spinning because we forgot about an fdevent
+    // by keeping track of how long fdevents have been continuously pending.
+    struct SpinCheck {
+        fdevent* fde;
+        std::chrono::steady_clock::time_point timestamp;
+        uint64_t cycle;
+    };
+    static auto& g_continuously_pending = *new std::unordered_map<uint64_t, SpinCheck>();
+
+    auto now = std::chrono::steady_clock::now();
+    for (auto* fde : g_pending_list) {
+        auto it = g_continuously_pending.find(fde->id);
+        if (it == g_continuously_pending.end()) {
+            g_continuously_pending[fde->id] =
+                    SpinCheck{.fde = fde, .timestamp = now, .cycle = cycle};
+        } else {
+            it->second.cycle = cycle;
+        }
+    }
+
+    for (auto it = g_continuously_pending.begin(); it != g_continuously_pending.end();) {
+        if (it->second.cycle != cycle) {
+            it = g_continuously_pending.erase(it);
+        } else {
+            // Use an absurdly long window, since all we really care about is
+            // getting a bugreport eventually.
+            if (now - it->second.timestamp > std::chrono::minutes(5)) {
+                LOG(FATAL_WITHOUT_ABORT) << "detected spin in fdevent: " << dump_fde(it->second.fde);
+#if defined(__linux__)
+                int fd = it->second.fde->fd.get();
+                std::string fd_path = android::base::StringPrintf("/proc/self/fd/%d", fd);
+                std::string path;
+                if (!android::base::Readlink(fd_path, &path)) {
+                    PLOG(FATAL_WITHOUT_ABORT) << "readlink of fd " << fd << " failed";
+                }
+                LOG(FATAL_WITHOUT_ABORT) << "fd " << fd << " = " << path;
+#endif
+                abort();
+            }
+            ++it;
+        }
+    }
+}
+
 void fdevent_loop() {
     set_main_thread();
     fdevent_run_setup();
 
+    uint64_t cycle = 0;
     while (true) {
         if (terminate_loop) {
             return;
@@ -365,6 +417,8 @@
 
         fdevent_process();
 
+        fdevent_check_spin(cycle++);
+
         while (!g_pending_list.empty()) {
             fdevent* fde = g_pending_list.front();
             g_pending_list.pop_front();
diff --git a/adb/fdevent.h b/adb/fdevent.h
index 69c4072..d501b86 100644
--- a/adb/fdevent.h
+++ b/adb/fdevent.h
@@ -32,8 +32,7 @@
 typedef void (*fd_func)(int fd, unsigned events, void *userdata);
 
 struct fdevent {
-    fdevent* next = nullptr;
-    fdevent* prev = nullptr;
+    uint64_t id;
 
     unique_fd fd;
     int force_eof = 0;
diff --git a/adb/services.cpp b/adb/services.cpp
index a757d90..b613d83 100644
--- a/adb/services.cpp
+++ b/adb/services.cpp
@@ -181,6 +181,29 @@
     kick_transport(t);
 }
 
+static void spin_service(int fd, void*) {
+    unique_fd sfd(fd);
+
+    if (!__android_log_is_debuggable()) {
+        WriteFdExactly(sfd.get(), "refusing to spin on non-debuggable build\n");
+        return;
+    }
+
+    // A service that creates an fdevent that's always pending, and then ignores it.
+    unique_fd pipe_read, pipe_write;
+    if (!Pipe(&pipe_read, &pipe_write)) {
+        WriteFdExactly(sfd.get(), "failed to create pipe\n");
+        return;
+    }
+
+    fdevent_run_on_main_thread([fd = pipe_read.release()]() {
+        fdevent* fde = fdevent_create(fd, [](int, unsigned, void*) {}, nullptr);
+        fdevent_add(fde, FDE_READ);
+    });
+
+    WriteFdExactly(sfd.get(), "spinning\n");
+}
+
 int reverse_service(const char* command, atransport* transport) {
     int s[2];
     if (adb_socketpair(s)) {
@@ -328,6 +351,8 @@
                                     reinterpret_cast<void*>(1));
     } else if (!strcmp(name, "reconnect")) {
         ret = create_service_thread("reconnect", reconnect_service, transport);
+    } else if (!strcmp(name, "spin")) {
+        ret = create_service_thread("spin", spin_service, nullptr);
 #endif
     }
     if (ret >= 0) {