rl_lib.c

Go to the documentation of this file.

#include "rl_lib.h"

rl_state rl_get_status(void) {
    
    struct rl_status status;
    
    // get pid
    pid_t pid = get_pid();
    if(pid == FAILURE || kill(pid, 0) < 0) {
        // process not running
        status.state = RL_OFF;
    } else {
        // read status
        read_status(&status);
    }
    
    return status.state;
}

int rl_read_status(struct rl_status* status) {
    
    // get pid
    pid_t pid = get_pid();
    if(pid == FAILURE || kill(pid, 0) < 0) {
        // process not running
        status->state = RL_OFF;
    } else {
        // read status
        read_status(status);
    }
    
    return status->state;
}
void rl_read_calibration(struct rl_calibration* calibration_ptr, struct rl_conf* conf) {
    read_calibration(conf);
    memcpy(calibration_ptr, &calibration, sizeof(struct rl_calibration));
}

int rl_start(struct rl_conf* conf) {
    
    // check mode
    switch (conf->mode) {
        case LIMIT:
            break;
        case CONTINUOUS:
            // create deamon to run in background
            if (daemon(1, 1) < 0) {
                rl_log(ERROR, "failed to create background process");
                return SUCCESS;
            }
            break;
        case METER:
            // set meter config
            conf->update_rate = METER_UPDATE_RATE;
            conf->sample_limit = 0;
            conf->enable_web_server = 0;
            conf->file_format = NO_FILE;
            if(conf->sample_rate < MIN_ADC_RATE) {
                rl_log(WARNING, "too low sample rate. Setting rate to 1kSps");
                conf->sample_rate = MIN_ADC_RATE;
            }
            break;
        default:
            rl_log(ERROR, "wrong mode");
            return FAILURE;
    }
    
    // check input
    if(check_sample_rate(conf->sample_rate) == FAILURE) {
        rl_log(ERROR, "wrong sampling rate");
        return FAILURE;
    }
    if(check_update_rate(conf->update_rate) == FAILURE) {
        rl_log(ERROR, "wrong update rate");
        return FAILURE;
    }
    if(conf->update_rate != 1 && conf->enable_web_server == 1) {
        rl_log(WARNING, "webserver plot does not work with update rates >1. Disabling webserver ...");
        conf->enable_web_server = 0;
    }
    
    // store PID to file
    pid_t pid = getpid();
    set_pid(pid);
    
    // register signal handler (for stopping)
    if (signal(SIGQUIT, sig_handler) == SIG_ERR || signal(SIGINT, sig_handler) == SIG_ERR) {
        rl_log(ERROR, "can't register signal handler");
        return FAILURE;
    }
    
    // INITIATION
    hw_init(conf);
    
    rl_log(INFO, "sampling started");
    
    // SAMPLING
    hw_sample(conf);
    
    rl_log(INFO, "sampling finished");
    
    // FINISH
    hw_close(conf);
     
    return SUCCESS;
    
}


int rl_stop(void) {
    
    // check if running
    if(rl_get_status() != RL_RUNNING) {
        rl_log(ERROR, "RocketLogger not running");
        return FAILURE;
    }
    
    // ged pid
    pid_t pid = get_pid();
    
    // send stop signal
    kill(pid, SIGQUIT);
    
    return SUCCESS;
}