root/tools/thermal/thermometer/thermometer.c
// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
#define _GNU_SOURCE
#include <dirent.h>
#include <fcntl.h>
#include <getopt.h>
#include <regex.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/signalfd.h>
#include <sys/timerfd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
#include <linux/thermal.h>

#include <libconfig.h>
#include "thermal-tools.h"

#define CLASS_THERMAL "/sys/class/thermal"

enum {
        THERMOMETER_SUCCESS = 0,
        THERMOMETER_OPTION_ERROR,
        THERMOMETER_LOG_ERROR,
        THERMOMETER_CONFIG_ERROR,
        THERMOMETER_TIME_ERROR,
        THERMOMETER_INIT_ERROR,
        THERMOMETER_RUNTIME_ERROR
};

struct options {
        int loglvl;
        int logopt;
        int overwrite;
        int duration;
        const char *config;
        char postfix[PATH_MAX];
        char output[PATH_MAX];
};

struct tz_regex {
        regex_t regex;
        int polling;
};

struct configuration {
        struct tz_regex *tz_regex;
        int nr_tz_regex;

};

struct tz {
        FILE *file_out;
        int fd_temp;
        int fd_timer;
        int polling;
        const char *name;
};

struct thermometer {
        struct tz *tz;
        int nr_tz;
};

static struct tz_regex *configuration_tz_match(const char *expr,
                                               struct configuration *config)
{
        int i;

        for (i = 0; i < config->nr_tz_regex; i++) {

                if (!regexec(&config->tz_regex[i].regex, expr, 0, NULL, 0))
                        return &config->tz_regex[i];
        }

        return NULL;
}

static int configuration_default_init(struct configuration *config)
{
        config->tz_regex = realloc(config->tz_regex, sizeof(*config->tz_regex) *
                                   (config->nr_tz_regex + 1));

        if (regcomp(&config->tz_regex[config->nr_tz_regex].regex, ".*",
                    REG_NOSUB | REG_EXTENDED)) {
                ERROR("Invalid regular expression\n");
                return -1;
        }

        config->tz_regex[config->nr_tz_regex].polling = 250;
        config->nr_tz_regex = 1;

        return 0;
}

static int configuration_init(const char *path, struct configuration *config)
{
        config_t cfg;

        config_setting_t *tz;
        int i, length;

        if (path && access(path, F_OK)) {
                ERROR("'%s' is not accessible\n", path);
                return -1;
        }

        if (!path && !config->nr_tz_regex) {
                INFO("No thermal zones configured, using wildcard for all of them\n");
                return configuration_default_init(config);
        }

        config_init(&cfg);

        if (!config_read_file(&cfg, path)) {
                ERROR("Failed to parse %s:%d - %s\n", config_error_file(&cfg),
                      config_error_line(&cfg), config_error_text(&cfg));

                return -1;
        }

        tz = config_lookup(&cfg, "thermal-zones");
        if (!tz) {
                ERROR("No thermal zone configured to be monitored\n");
                return -1;
        }

        length = config_setting_length(tz);

        INFO("Found %d thermal zone(s) regular expression\n", length);

        for (i = 0; i < length; i++) {

                config_setting_t *node;
                const char *name;
                int polling;

                node = config_setting_get_elem(tz, i);
                if (!node) {
                        ERROR("Missing node name '%d'\n", i);
                        return -1;
                }

                if (!config_setting_lookup_string(node, "name", &name)) {
                        ERROR("Thermal zone name not found\n");
                        return -1;
                }

                if (!config_setting_lookup_int(node, "polling", &polling)) {
                        ERROR("Polling value not found");
                        return -1;
                }

                config->tz_regex = realloc(config->tz_regex, sizeof(*config->tz_regex) *
                                        (config->nr_tz_regex + 1));

                if (regcomp(&config->tz_regex[config->nr_tz_regex].regex, name,
                            REG_NOSUB | REG_EXTENDED)) {
                        ERROR("Invalid regular expression '%s'\n", name);
                        continue;
                }

                config->tz_regex[config->nr_tz_regex].polling = polling;
                config->nr_tz_regex++;

                INFO("Thermal zone regular expression '%s' with polling %d\n",
                     name, polling);
        }

        return 0;
}

static void usage(const char *cmd)
{
        printf("%s Version: %s\n", cmd, VERSION);
        printf("Usage: %s [options]\n", cmd);
        printf("\t-h, --help\t\tthis help\n");
        printf("\t-o, --output <dir>\toutput directory for temperature capture\n");
        printf("\t-c, --config <file>\tconfiguration file\n");
        printf("\t-d, --duration <seconds>\tcapture duration\n");
        printf("\t-l, --loglevel <level>\tlog level: ");
        printf("DEBUG, INFO, NOTICE, WARN, ERROR\n");
        printf("\t-p, --postfix <string>\tpostfix to be happened at the end of the files\n");
        printf("\t-s, --syslog\t\toutput to syslog\n");
        printf("\t-w, --overwrite\t\toverwrite the temperature capture files if they exist\n");
        printf("\n");
        exit(0);
}

static int options_init(int argc, char *argv[], struct options *options)
{
        int opt;
        time_t now = time(NULL);

        struct option long_options[] = {
                { "help",       no_argument, NULL, 'h' },
                { "config",     required_argument, NULL, 'c' },
                { "duration",   required_argument, NULL, 'd' },
                { "loglevel",   required_argument, NULL, 'l' },
                { "postfix",    required_argument, NULL, 'p' },
                { "output",     required_argument, NULL, 'o' },
                { "syslog",     required_argument, NULL, 's' },
                { "overwrite",  no_argument, NULL, 'w' },
                { 0, 0, 0, 0 }
        };

        strftime(options->postfix, sizeof(options->postfix),
                 "-%Y-%m-%d_%H:%M:%S", gmtime(&now));

        while (1) {

                int optindex = 0;

                opt = getopt_long(argc, argv, "ho:c:d:l:p:sw", long_options, &optindex);
                if (opt == -1)
                        break;

                switch (opt) {
                case 'c':
                        options->config = optarg;
                        break;
                case 'd':
                        options->duration = atoi(optarg) * 1000;
                        break;
                case 'l':
                        options->loglvl = log_str2level(optarg);
                        break;
                case 'h':
                        usage(basename(argv[0]));
                        break;
                case 'p':
                        strcpy(options->postfix, optarg);
                        break;
                case 'o':
                        strcpy(options->output, optarg);
                        break;
                case 's':
                        options->logopt = TO_SYSLOG;
                        break;
                case 'w':
                        options->overwrite = 1;
                        break;
                default: /* '?' */
                        ERROR("Usage: %s --help\n", argv[0]);
                        return -1;
                }
        }

        return 0;
}

static int thermometer_add_tz(const char *path, const char *name, int polling,
                              struct thermometer *thermometer)
{
        int fd;
        char tz_path[PATH_MAX];
        struct tz *tz;

        sprintf(tz_path, CLASS_THERMAL"/%s/temp", path);

        fd = open(tz_path, O_RDONLY);
        if (fd < 0) {
                ERROR("Failed to open '%s': %m\n", tz_path);
                return -1;
        }

        tz = realloc(thermometer->tz, sizeof(*thermometer->tz) * (thermometer->nr_tz + 1));
        if (!tz) {
                ERROR("Failed to allocate thermometer->tz\n");
                return -1;
        }

        thermometer->tz = tz;
        thermometer->tz[thermometer->nr_tz].fd_temp = fd;
        thermometer->tz[thermometer->nr_tz].name = strdup(name);
        thermometer->tz[thermometer->nr_tz].polling = polling;
        thermometer->nr_tz++;

        INFO("Added thermal zone '%s->%s (polling:%d)'\n", path, name, polling);

        return 0;
}

static int thermometer_init(struct configuration *config,
                            struct thermometer *thermometer)
{
        DIR *dir;
        struct dirent *dirent;
        struct tz_regex *tz_regex;
        const char *tz_dirname = "thermal_zone";

        if (mainloop_init()) {
                ERROR("Failed to start mainloop\n");
                return -1;
        }

        dir = opendir(CLASS_THERMAL);
        if (!dir) {
                ERROR("failed to open '%s'\n", CLASS_THERMAL);
                return -1;
        }

        while ((dirent = readdir(dir))) {
                char tz_type[THERMAL_NAME_LENGTH];
                char tz_path[PATH_MAX];
                FILE *tz_file;

                if (strncmp(dirent->d_name, tz_dirname, strlen(tz_dirname)))
                        continue;

                sprintf(tz_path, CLASS_THERMAL"/%s/type", dirent->d_name);

                tz_file = fopen(tz_path, "r");
                if (!tz_file) {
                        ERROR("Failed to open '%s': %m", tz_path);
                        continue;
                }

                fscanf(tz_file, "%s", tz_type);

                fclose(tz_file);

                tz_regex = configuration_tz_match(tz_type, config);
                if (!tz_regex)
                        continue;

                if (thermometer_add_tz(dirent->d_name, tz_type,
                                       tz_regex->polling, thermometer))
                        continue;
        }

        closedir(dir);

        return 0;
}

static int timer_temperature_callback(int fd, void *arg)
{
        struct tz *tz = arg;
        char buf[16] = { 0 };

        pread(tz->fd_temp, buf, sizeof(buf), 0);

        fprintf(tz->file_out, "%ld %s", getuptimeofday_ms(), buf);

        read(fd, buf, sizeof(buf));

        return 0;
}

static int thermometer_start(struct thermometer *thermometer,
                             struct options *options)
{
        struct itimerspec timer_it = { 0 };
        char *path;
        FILE *f;
        int i;

        INFO("Capturing %d thermal zone(s) temperature...\n", thermometer->nr_tz);

        if (access(options->output, F_OK) && mkdir(options->output, 0700)) {
                ERROR("Failed to create directory '%s'\n", options->output);
                return -1;
        }

        for (i = 0; i < thermometer->nr_tz; i++) {

                asprintf(&path, "%s/%s%s", options->output,
                         thermometer->tz[i].name, options->postfix);

                if (!options->overwrite && !access(path, F_OK)) {
                        ERROR("'%s' already exists\n", path);
                        return -1;
                }

                f = fopen(path, "w");
                if (!f) {
                        ERROR("Failed to create '%s':%m\n", path);
                        return -1;
                }

                fprintf(f, "timestamp(ms) %s(°mC)\n", thermometer->tz[i].name);

                thermometer->tz[i].file_out = f;

                DEBUG("Created '%s' file for thermal zone '%s'\n", path, thermometer->tz[i].name);

                /*
                 * Create polling timer
                 */
                thermometer->tz[i].fd_timer = timerfd_create(CLOCK_MONOTONIC, 0);
                if (thermometer->tz[i].fd_timer < 0) {
                        ERROR("Failed to create timer for '%s': %m\n",
                              thermometer->tz[i].name);
                        return -1;
                }

                DEBUG("Watching '%s' every %d ms\n",
                      thermometer->tz[i].name, thermometer->tz[i].polling);

                timer_it.it_interval = timer_it.it_value =
                        msec_to_timespec(thermometer->tz[i].polling);

                if (timerfd_settime(thermometer->tz[i].fd_timer, 0,
                                    &timer_it, NULL) < 0)
                        return -1;

                if (mainloop_add(thermometer->tz[i].fd_timer,
                                 timer_temperature_callback,
                                 &thermometer->tz[i]))
                        return -1;
        }

        return 0;
}

static int thermometer_execute(int argc, char *argv[], char *const envp[], pid_t *pid)
{
        if (!argc)
                return 0;

        *pid = fork();
        if (*pid < 0) {
                ERROR("Failed to fork process: %m");
                return -1;
        }

        if (!(*pid)) {
                execvpe(argv[0], argv, envp);
                exit(1);
        }

        return 0;
}

static int kill_process(__maybe_unused int fd, void *arg)
{
        pid_t pid = *(pid_t *)arg;

        if (kill(pid, SIGTERM))
                ERROR("Failed to send SIGTERM signal to '%d': %p\n", pid);
        else if (waitpid(pid, NULL, 0))
                ERROR("Failed to wait pid '%d': %p\n", pid);

        mainloop_exit();

        return 0;
}

static int exit_mainloop(__maybe_unused int fd, __maybe_unused void *arg)
{
        mainloop_exit();
        return 0;
}

static int thermometer_wait(struct options *options, pid_t pid)
{
        int fd;
        sigset_t mask;

        /*
         * If there is a duration specified, we will exit the mainloop
         * and gracefully close all the files which will flush the
         * file system cache
         */
        if (options->duration) {
                struct itimerspec timer_it = { 0 };

                timer_it.it_value = msec_to_timespec(options->duration);

                fd = timerfd_create(CLOCK_MONOTONIC, 0);
                if (fd < 0) {
                        ERROR("Failed to create duration timer: %m\n");
                        return -1;
                }

                if (timerfd_settime(fd, 0, &timer_it, NULL)) {
                        ERROR("Failed to set timer time: %m\n");
                        return -1;
                }

                if (mainloop_add(fd, pid < 0 ? exit_mainloop : kill_process, &pid)) {
                        ERROR("Failed to set timer exit mainloop callback\n");
                        return -1;
                }
        }

        /*
         * We want to catch any keyboard interrupt, as well as child
         * signals if any in order to exit properly
         */
        sigemptyset(&mask);
        sigaddset(&mask, SIGINT);
        sigaddset(&mask, SIGQUIT);
        sigaddset(&mask, SIGCHLD);

        if (sigprocmask(SIG_BLOCK, &mask, NULL)) {
                ERROR("Failed to set sigprocmask: %m\n");
                return -1;
        }

        fd = signalfd(-1, &mask, 0);
        if (fd < 0) {
                ERROR("Failed to set the signalfd: %m\n");
                return -1;
        }

        if (mainloop_add(fd, exit_mainloop, NULL)) {
                ERROR("Failed to set timer exit mainloop callback\n");
                return -1;
        }

        return mainloop(-1);
}

static int thermometer_stop(struct thermometer *thermometer)
{
        int i;

        INFO("Closing/flushing output files\n");

        for (i = 0; i < thermometer->nr_tz; i++)
                fclose(thermometer->tz[i].file_out);

        return 0;
}

int main(int argc, char *argv[], char *const envp[])
{
        struct options options = {
                .loglvl = LOG_DEBUG,
                .logopt = TO_STDOUT,
                .output = ".",
        };
        struct configuration config = { 0 };
        struct thermometer thermometer = { 0 };

        pid_t pid = -1;

        if (options_init(argc, argv, &options))
                return THERMOMETER_OPTION_ERROR;

        if (log_init(options.loglvl, argv[0], options.logopt))
                return THERMOMETER_LOG_ERROR;

        if (configuration_init(options.config, &config))
                return THERMOMETER_CONFIG_ERROR;

        if (uptimeofday_init())
                return THERMOMETER_TIME_ERROR;

        if (thermometer_init(&config, &thermometer))
                return THERMOMETER_INIT_ERROR;

        if (thermometer_start(&thermometer, &options))
                return THERMOMETER_RUNTIME_ERROR;

        if (thermometer_execute(argc - optind, &argv[optind], envp, &pid))
                return THERMOMETER_RUNTIME_ERROR;

        if (thermometer_wait(&options, pid))
                return THERMOMETER_RUNTIME_ERROR;

        if (thermometer_stop(&thermometer))
                return THERMOMETER_RUNTIME_ERROR;

        return THERMOMETER_SUCCESS;
}