Add android::base::GetPids() function to return all pids
We loop over /proc to iterate through pids in a lot of code, so let's
consolidate this into a single function in libbase.
Test: new unit test
Change-Id: I908fab90b603546d0e3e8b8acdc8dadfc3552d62
diff --git a/base/process.cpp b/base/process.cpp
new file mode 100644
index 0000000..b8cabf6
--- /dev/null
+++ b/base/process.cpp
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "android-base/process.h"
+
+namespace android {
+namespace base {
+
+void AllPids::PidIterator::Increment() {
+ if (!dir_) {
+ return;
+ }
+
+ dirent* de;
+ while ((de = readdir(dir_.get())) != nullptr) {
+ pid_t pid = atoi(de->d_name);
+ if (pid != 0) {
+ pid_ = pid;
+ return;
+ }
+ }
+ pid_ = -1;
+}
+
+} // namespace base
+} // namespace android