libprocinfo: add support for parsing process state.

Bug: http://b/63008395
Test: libprocinfo_test32
Change-Id: I20a337bb5075bcdb325d2b48e174b0b5ef896261

1 files changed, 34 insertions, 0 deletions

diff --git a/libprocinfo/process_test.cpp b/libprocinfo/process_test.cpp
index 5ffd2365b..9da927899 100644
--- a/libprocinfo/process_test.cpp
+++ b/libprocinfo/process_test.cpp
@@ -21,6 +21,7 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <chrono>
 #include <set>
 #include <thread>
 #include <vector>
@@ -29,6 +30,8 @@
 
 #include <android-base/stringprintf.h>
 
+using namespace std::chrono_literals;
+
 #if !defined(__BIONIC__)
 #include <syscall.h>
 static pid_t gettid() {
@@ -82,3 +85,34 @@ TEST(process_info, process_tids_smoke) {
     }
   }).join();
 }
+
+TEST(process_info, process_state) {
+  int pipefd[2];
+  ASSERT_EQ(0, pipe2(pipefd, O_CLOEXEC));
+  pid_t forkpid = fork();
+
+  ASSERT_NE(-1, forkpid);
+  if (forkpid == 0) {
+    close(pipefd[1]);
+    char buf;
+    TEMP_FAILURE_RETRY(read(pipefd[0], &buf, 1));
+    _exit(0);
+  }
+
+  // Give the child some time to get to the read.
+  std::this_thread::sleep_for(100ms);
+
+  android::procinfo::ProcessInfo procinfo;
+  ASSERT_TRUE(android::procinfo::GetProcessInfo(forkpid, &procinfo));
+  ASSERT_EQ(android::procinfo::kProcessStateSleeping, procinfo.state);
+
+  ASSERT_EQ(0, kill(forkpid, SIGKILL));
+
+  // Give the kernel some time to kill the child.
+  std::this_thread::sleep_for(100ms);
+
+  ASSERT_TRUE(android::procinfo::GetProcessInfo(forkpid, &procinfo));
+  ASSERT_EQ(android::procinfo::kProcessStateZombie, procinfo.state);
+
+  ASSERT_EQ(forkpid, waitpid(forkpid, nullptr, 0));
+}