From 4175cee3cc6feda91d0ffaa5301b2119089a24f6 Mon Sep 17 00:00:00 2001
From: Josh Gao <jmgao@google.com>
Date: Fri, 4 Jan 2019 13:57:09 -0800
Subject: [PATCH] debuggerd_client: resolve tid to tgid when dumping Java
 stacks.

Bug: http://b/121438213
Test: debuggerd_test32
Test: debuggerd_test64
Change-Id: I4d114c8b0c4586ba64de5b45b47b0ec5c10354f8
---
 debuggerd/Android.bp                  |  1 +
 debuggerd/client/debuggerd_client.cpp | 17 +++++++++++++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index 516748176..10f52f45f 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -150,6 +150,7 @@ cc_library {
     shared_libs: [
         "libbase",
         "libcutils",
+        "libprocinfo",
     ],
 
     export_header_lib_headers: ["libdebuggerd_common_headers"],
diff --git a/debuggerd/client/debuggerd_client.cpp b/debuggerd/client/debuggerd_client.cpp
index 77f3515a4..785df99c5 100644
--- a/debuggerd/client/debuggerd_client.cpp
+++ b/debuggerd/client/debuggerd_client.cpp
@@ -33,6 +33,7 @@
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
 #include <cutils/sockets.h>
+#include <procinfo/process.h>
 
 #include "debuggerd/handler.h"
 #include "protocol.h"
@@ -62,8 +63,20 @@ static void populate_timeval(struct timeval* tv, const Duration& duration) {
   tv->tv_usec = static_cast<long>(microseconds.count());
 }
 
-bool debuggerd_trigger_dump(pid_t pid, DebuggerdDumpType dump_type, unsigned int timeout_ms,
+bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int timeout_ms,
                             unique_fd output_fd) {
+  pid_t pid = tid;
+  if (dump_type == kDebuggerdJavaBacktrace) {
+    // Java dumps always get sent to the tgid, so we need to resolve our tid to a tgid.
+    android::procinfo::ProcessInfo procinfo;
+    std::string error;
+    if (!android::procinfo::GetProcessInfo(tid, &procinfo, &error)) {
+      LOG(ERROR) << "libdebugged_client: failed to get process info: " << error;
+      return -1;
+    }
+    pid = procinfo.pid;
+  }
+
   LOG(INFO) << "libdebuggerd_client: started dumping process " << pid;
   unique_fd sockfd;
   const auto end = std::chrono::steady_clock::now() + std::chrono::milliseconds(timeout_ms);
@@ -162,7 +175,7 @@ bool debuggerd_trigger_dump(pid_t pid, DebuggerdDumpType dump_type, unsigned int
     return false;
   }
 
-  if (!send_signal(pid, dump_type)) {
+  if (!send_signal(tid, dump_type)) {
     return false;
   }