Timetest: Clean up

Clean up the code a little.

The removed TEMP_FAILURE_RETRY is actually wrong. The others are either
superfluous or needed.

Be more direct with error returns.

For EBUSY, loop at most ten times, with sleep.

Use unique_fd for descriptor tracking/close.

Bug: 76008092
Test: atest time-unit-tests
Change-Id: Id7176e0237a416a4bb19d72c47b8e1a2f6b57ca5

3 files changed, 41 insertions, 45 deletions

diff --git a/tests/timetest/Android.bp b/tests/timetest/Android.bp
new file mode 100644
index 00000000..998faeff
--- /dev/null
+++ b/tests/timetest/Android.bp
@@ -0,0 +1,17 @@
+// Copyright 2006 The Android Open Source Project
+
+cc_test {
+  name: "time-unit-tests",
+  cflags: [
+    "-fstack-protector-all",
+    "-g",
+    "-Wextra",
+    "-fno-builtin",
+  ],
+  srcs: [
+    "rtc_test.cpp",
+  ],
+  shared_libs: [
+    "libbase",
+  ],
+}
diff --git a/tests/timetest/Android.mk b/tests/timetest/Android.mk
index af3447fd..be311fa4 100644
--- a/tests/timetest/Android.mk
+++ b/tests/timetest/Android.mk
@@ -10,26 +10,3 @@ LOCAL_MODULE_TAGS := tests
 LOCAL_FORCE_STATIC_EXECUTABLE := true
 LOCAL_STATIC_LIBRARIES := libc
 include $(BUILD_NATIVE_TEST)
-
-# -----------------------------------------------------------------------------
-# Unit tests.
-# -----------------------------------------------------------------------------
-
-test_c_flags := \
-    -fstack-protector-all \
-    -g \
-    -Wall -Wextra \
-    -Werror \
-    -fno-builtin \
-
-test_src_files := \
-    rtc_test.cpp
-
-include $(CLEAR_VARS)
-LOCAL_MODULE := time-unit-tests
-LOCAL_COMPATIBILITY_SUITE := device-tests
-LOCAL_MODULE_TAGS := tests
-LOCAL_CFLAGS += $(test_c_flags)
-LOCAL_SRC_FILES := $(test_src_files)
-include $(BUILD_NATIVE_TEST)
-
diff --git a/tests/timetest/rtc_test.cpp b/tests/timetest/rtc_test.cpp
index 26ca13ad..e7874b1d 100644
--- a/tests/timetest/rtc_test.cpp
+++ b/tests/timetest/rtc_test.cpp
@@ -24,49 +24,51 @@
 
 #include <gtest/gtest.h>
 
+#include <android-base/unique_fd.h>
+
 static int hwtime(int flag, int request, struct rtc_time *tm) {
   static const char rtc[] = "/dev/rtc0";
 
-  int ret = TEMP_FAILURE_RETRY(access(rtc, flag & O_WRONLY) ? W_OK : R_OK);
+  int ret = access(rtc, flag & O_WRONLY);
   if (ret < 0) {
-    ret = -errno;
-  }
-  if (ret == -EACCES) {
-    return ret;
+    return -errno;
   }
 
   if (flag & O_WRONLY) {
     struct stat st;
     ret = TEMP_FAILURE_RETRY(stat(rtc, &st));
     if (ret < 0) {
-      ret = -errno;
+      return -errno;
     } else if (!(st.st_mode & (S_IWUSR|S_IWGRP|S_IWOTH))) {
-      ret = -EACCES;
+      return -EACCES;
     }
   }
-  if (ret == -EACCES) {
-    return ret;
-  }
 
-  do {
+  for (int count = 0; count < 10; count++) {
     ret = TEMP_FAILURE_RETRY(open(rtc, flag));
     if (ret < 0) {
-      ret = -errno;
+      if (errno == EBUSY) {
+        sleep(1);
+        continue;
+      }
+      return -errno;
     }
-  } while (ret == -EBUSY);
-  if (ret < 0) {
-    return ret;
+    break;
   }
+  android::base::unique_fd fd(ret);
 
-  int fd = ret;
-  do {
-    ret = TEMP_FAILURE_RETRY(ioctl(fd, request, tm));
+  for (int count = 0; count < 10; count++) {
+    ret = TEMP_FAILURE_RETRY(ioctl(fd.get(), request, tm));
     if (ret < 0) {
-      ret = -errno;
+      if (errno == EBUSY) {
+        sleep(1);
+        continue;
+      }
+      return -errno;
     }
-  } while (ret == -EBUSY);
-  close(fd);
-  return ret;
+    return ret;
+  };
+  return -EBUSY;
 }
 
 static int rd_hwtime(struct rtc_time *tm) {