1 files changed, 200 insertions, 0 deletions
diff --git a/pwrstats_util/pwrstats_util.cpp b/pwrstats_util/pwrstats_util.cpp
new file mode 100644
index 0000000..b28b4b0
--- /dev/null
+++ b/pwrstats_util/pwrstats_util.cpp
@@ -0,0 +1,200 @@
+/*
+ * 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.
+ */
+#define LOG_TAG "pwrstats_util"
+
+#include <android-base/logging.h>
+#include <fcntl.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <chrono>
+#include <csignal>
+#include <fstream>
+#include <iostream>
+#include <unordered_map>
+
+#include "PowerStatsAggregator.h"
+
+namespace {
+volatile std::sig_atomic_t gSignalStatus;
+}
+
+class Options {
+  public:
+    bool daemonMode;
+    std::string filePath;
+};
+
+static void signalHandler(int signal) {
+    gSignalStatus = signal;
+}
+
+static void printHelp() {
+    std::cout << "pwrstats_util: Prints out device power stats in the form of key/value pairs."
+              << std::endl
+              << "-d </path/to/file> : daemon mode. Spawns a daemon process and prints out"
+              << " its <pid>. kill -INT <pid> will trigger a write to specified file." << std::endl;
+}
+
+static Options parseArgs(int argc, char** argv) {
+    Options opt = {
+            .daemonMode = false,
+    };
+
+    int c;
+    while ((c = getopt(argc, argv, "d:h")) != -1) {
+        switch (c) {
+            case 'd':
+                opt.daemonMode = true;
+                opt.filePath = std::string(optarg);
+                break;
+            case 'h':
+                printHelp();
+                exit(EXIT_SUCCESS);
+            default:
+                exit(EXIT_FAILURE);
+        }
+    }
+    return opt;
+}
+
+static void snapshot(const PowerStatsAggregator& agg) {
+    std::unordered_map<std::string, uint64_t> data;
+    int ret = agg.getData(&data);
+    if (ret) {
+        exit(EXIT_FAILURE);
+    }
+
+    for (auto const& datum : data) {
+        std::cout << datum.first << "=" << datum.second << std::endl;
+    }
+
+    exit(EXIT_SUCCESS);
+}
+
+static void daemon(const std::string& filePath, const PowerStatsAggregator& agg) {
+    // Following a subset of steps outlined in http://man7.org/linux/man-pages/man7/daemon.7.html
+
+    // Call fork to create child process
+    pid_t pid;
+    if ((pid = fork()) < 0) {
+        LOG(ERROR) << "can't fork" << std::endl;
+        exit(EXIT_FAILURE);
+    } else if (pid != 0) {
+        std::cout << "pid = " << pid << std::endl;
+        exit(EXIT_SUCCESS);
+    }
+    // Daemon process:
+
+    // Get maximum number of file descriptors
+    struct rlimit rl;
+    if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
+        LOG(ERROR) << "can't get file limit" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    // Close all open file descriptors
+    if (rl.rlim_max == RLIM_INFINITY) {
+        rl.rlim_max = 1024;
+    }
+    for (int i = 0; i < rl.rlim_max; i++) {
+        close(i);
+    }
+
+    // Detach from any terminal and create an independent session
+    if (setsid() < 0) {
+        LOG(ERROR) << "SID creation failed";
+        exit(EXIT_FAILURE);
+    }
+
+    // connect /dev/null to standard input, output, and error.
+    int devnull = open("/dev/null", O_RDWR | O_CLOEXEC);
+    dup2(devnull, STDIN_FILENO);
+    dup2(devnull, STDOUT_FILENO);
+    dup2(devnull, STDERR_FILENO);
+
+    // Reset the umask to 0
+    umask(0);
+
+    // Change the current directory to the root
+    // directory (/), in order to avoid that the daemon involuntarily
+    // blocks mount points from being unmounted
+    if (chdir("/") < 0) {
+        LOG(ERROR) << "can't change directory to /" << std::endl;
+        exit(EXIT_FAILURE);
+    }
+
+    // Install a signal handler
+    std::signal(SIGINT, signalHandler);
+
+    // get the start_data
+    auto start_time = std::chrono::system_clock::now();
+
+    std::unordered_map<std::string, uint64_t> start_data;
+    int ret = agg.getData(&start_data);
+    if (ret) {
+        LOG(ERROR) << "failed to get start data";
+        exit(EXIT_FAILURE);
+    }
+
+    // Wait for INT signal
+    while (gSignalStatus != SIGINT) {
+        pause();
+    }
+
+    // get the end data
+    std::unordered_map<std::string, uint64_t> end_data;
+    ret = agg.getData(&end_data);
+    if (ret) {
+        LOG(ERROR) << "failed to get end data";
+        exit(EXIT_FAILURE);
+    }
+    auto end_time = std::chrono::system_clock::now();
+
+    std::chrono::duration<double> elapsed_seconds = end_time - start_time;
+
+    // Write data to file
+    std::ofstream myfile(filePath);
+    if (!myfile.is_open()) {
+        LOG(ERROR) << "failed to open file";
+        exit(EXIT_FAILURE);
+    }
+    myfile << "elapsed time: " << elapsed_seconds.count() << "s" << std::endl;
+    for (auto const& datum : end_data) {
+        myfile << datum.first << "=" << datum.second - start_data[datum.first] << std::endl;
+    }
+
+    myfile.close();
+
+    exit(EXIT_SUCCESS);
+}
+
+static void runWithOptions(const Options& opt, const PowerStatsAggregator& agg) {
+    if (opt.daemonMode) {
+        daemon(opt.filePath, agg);
+    } else {
+        snapshot(agg);
+    }
+}
+
+int run(int argc, char** argv, const PowerStatsAggregator& agg) {
+    Options opt = parseArgs(argc, argv);
+
+    runWithOptions(opt, agg);
+
+    return 0;
+}