Revert of Multiprocess test client: Android child process launcher rework.

base/process/process_util_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #define _CRT_SECURE_NO_WARNINGS
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <limits>
@@ skipping 239 matching lines @@
   base::ProcessId id1 = base::GetProcId(GetCurrentProcess());
   EXPECT_NE(0ul, id1);
   base::Process process = SpawnChild("SimpleChildProcess");
   ASSERT_TRUE(process.IsValid());
   base::ProcessId id2 = process.Pid();
   EXPECT_NE(0ul, id2);
   EXPECT_NE(id1, id2);
 }
 #endif  // defined(OS_WIN)
 
-#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
+#if !defined(OS_MACOSX)
 // This test is disabled on Mac, since it's flaky due to ReportCrash
 // taking a variable amount of time to parse and load the debug and
 // symbol data for this unit test's executable before firing the
 // signal handler.
 //
 // TODO(gspencer): turn this test process into a very small program
 // with no symbols (instead of using the multiprocess testing
 // framework) to reduce the ReportCrash overhead.
-//
-// It is disabled on Android as MultiprocessTests are started as services that
-// the framework restarts on crashes.
 const char kSignalFileCrash[] = "CrashingChildProcess.die";
 
 MULTIPROCESS_TEST_MAIN(CrashingChildProcess) {
   WaitToDie(ProcessUtilTest::GetSignalFilePath(kSignalFileCrash).c_str());
-#if defined(OS_POSIX)
+#if defined(OS_ANDROID)
+  // Android L+ expose signal and sigaction symbols that override the system
+  // ones. There is a bug in these functions where a request to set the handler
+  // to SIG_DFL is ignored. In that case, an infinite loop is entered as the
+  // signal is repeatedly sent to the crash dump signal handler.
+  // To work around this, directly call the system's sigaction.
+  struct kernel_sigaction sa;
+  memset(&sa, 0, sizeof(sa));
+  sys_sigemptyset(&sa.sa_mask);
+  sa.sa_handler_ = SIG_DFL;
+  sa.sa_flags = SA_RESTART;
+  sys_rt_sigaction(SIGSEGV, &sa, NULL, sizeof(kernel_sigset_t));
+#elif defined(OS_POSIX)
   // Have to disable to signal handler for segv so we can get a crash
   // instead of an abnormal termination through the crash dump handler.
   ::signal(SIGSEGV, SIG_DFL);
 #endif
   // Make this process have a segmentation fault.
   volatile int* oops = NULL;
   *oops = 0xDEAD;
   return 1;
 }
 
@@ skipping 28 matching lines @@
   int signaled = WIFSIGNALED(exit_code);
   EXPECT_NE(0, signaled);
   int signal = WTERMSIG(exit_code);
   EXPECT_EQ(SIGSEGV, signal);
 #endif
 
   // Reset signal handlers back to "normal".
   base::debug::EnableInProcessStackDumping();
   remove(signal_file.c_str());
 }
-#endif  // !defined(OS_MACOSX) && !defined(OS_ANDROID)
+#endif  // !defined(OS_MACOSX)
 
 MULTIPROCESS_TEST_MAIN(KilledChildProcess) {
   WaitToDie(ProcessUtilTest::GetSignalFilePath(kSignalFileKill).c_str());
 #if defined(OS_WIN)
   // Kill ourselves.
   HANDLE handle = ::OpenProcess(PROCESS_ALL_ACCESS, 0, ::GetCurrentProcessId());
   ::TerminateProcess(handle, kExpectedKilledExitCode);
 #elif defined(OS_POSIX)
   // Send a SIGKILL to this process, just like the OOM killer would.
   ::kill(getpid(), SIGKILL);
@@ skipping 675 matching lines @@
   options.current_directory = base::FilePath("/dev/null");
 
   base::Process process(SpawnChildWithOptions("SimpleChildProcess", options));
   ASSERT_TRUE(process.IsValid());
 
   int exit_code = kSuccess;
   EXPECT_TRUE(process.WaitForExit(&exit_code));
   EXPECT_NE(kSuccess, exit_code);
 }
 #endif  // defined(OS_LINUX)