C++ IS_FUNC_DEFINED函数代码示例

mraa_result_t
mraa_gpio_close(mraa_gpio_context dev)
{
    mraa_result_t result = MRAA_SUCCESS;

    if (dev == NULL) {
        syslog(LOG_ERR, "gpio: close: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, gpio_close_replace)) {
        return dev->advance_func->gpio_close_replace(dev);
    }


    if (IS_FUNC_DEFINED(dev, gpio_close_pre)) {
        result = dev->advance_func->gpio_close_pre(dev);
    }

    if (dev->value_fp != -1) {
        close(dev->value_fp);
    }
    mraa_gpio_unexport(dev);
    free(dev);
    return result;
}

static mraa_i2c_context
mraa_i2c_init_internal(mraa_adv_func_t* advance_func, unsigned int bus)
{
    mraa_result_t status = MRAA_SUCCESS;

    if (advance_func == NULL)
        return NULL;

    mraa_i2c_context dev = (mraa_i2c_context) calloc(1, sizeof(struct _i2c));
    if (dev == NULL) {
        syslog(LOG_CRIT, "i2c: Failed to allocate memory for context");
        return NULL;
    }

    dev->advance_func = advance_func;
    dev->busnum = bus;

    if (IS_FUNC_DEFINED(dev, i2c_init_pre)) {
        status = advance_func->i2c_init_pre(bus);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    }

    if (IS_FUNC_DEFINED(dev, i2c_init_bus_replace)) {
        status = dev->advance_func->i2c_init_bus_replace(dev);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    } else {
        char filepath[32];
        snprintf(filepath, 32, "/dev/i2c-%u", bus);
        if ((dev->fh = open(filepath, O_RDWR)) < 1) {
            syslog(LOG_ERR, "i2c: Failed to open requested i2c port %s", filepath);
            status = MRAA_ERROR_NO_RESOURCES;
            goto init_internal_cleanup;
        }

        if (ioctl(dev->fh, I2C_FUNCS, &dev->funcs) < 0) {
            syslog(LOG_CRIT, "i2c: Failed to get I2C_FUNC map from device");
            dev->funcs = 0;
        }
    }

    if (IS_FUNC_DEFINED(dev, i2c_init_post)) {
        status = dev->advance_func->i2c_init_post(dev);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    }


init_internal_cleanup:
    if (status == MRAA_SUCCESS) {
        return dev;
    } else {
        if (dev != NULL)
            free(dev);
        return NULL;
   }
}

mraa_result_t
mraa_gpio_mode(mraa_gpio_context dev, mraa_gpio_mode_t mode)
{
    if (IS_FUNC_DEFINED(dev, gpio_mode_replace))
        return dev->advance_func->gpio_mode_replace(dev, mode);

    if (IS_FUNC_DEFINED(dev, gpio_mode_pre)) {
        mraa_result_t pre_ret = (dev->advance_func->gpio_mode_pre(dev, mode));
        if (pre_ret != MRAA_SUCCESS)
            return pre_ret;
    }

    if (dev->value_fp != -1) {
        close(dev->value_fp);
        dev->value_fp = -1;
    }

    char filepath[MAX_SIZE];
    snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);

    int drive = open(filepath, O_WRONLY);
    if (drive == -1) {
        syslog(LOG_ERR, "gpio: Failed to open drive for writing");
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    char bu[MAX_SIZE];
    int length;
    switch (mode) {
        case MRAA_GPIO_STRONG:
            length = snprintf(bu, sizeof(bu), "strong");
            break;
        case MRAA_GPIO_PULLUP:
            length = snprintf(bu, sizeof(bu), "pullup");
            break;
        case MRAA_GPIO_PULLDOWN:
            length = snprintf(bu, sizeof(bu), "pulldown");
            break;
        case MRAA_GPIO_HIZ:
            length = snprintf(bu, sizeof(bu), "hiz");
            break;
        default:
            close(drive);
            return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
    }
    if (write(drive, bu, length * sizeof(char)) == -1) {
        syslog(LOG_ERR, "gpio: Failed to write to drive mode");
        close(drive);
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    close(drive);
    if (IS_FUNC_DEFINED(dev, gpio_mode_post))
        return dev->advance_func->gpio_mode_post(dev, mode);
    return MRAA_SUCCESS;
}

mraa_result_t
mraa_pwm_enable(mraa_pwm_context dev, int enable)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: enable: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_enable_replace)) {
        return dev->advance_func->pwm_enable_replace(dev, enable);
    }

    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);

    int enable_f = open(bu, O_RDWR);

    if (enable_f == -1) {
        syslog(LOG_ERR, "pwm_enable: pwm%i: Failed to open enable for writing: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[2];
    int size = snprintf(out, sizeof(out), "%d", enable);
    if (write(enable_f, out, size * sizeof(char)) == -1) {
        syslog(LOG_ERR, "pwm_enable: pwm%i: Failed to write to enable: %s", dev->pin, strerror(errno));
        close(enable_f);
        return MRAA_ERROR_UNSPECIFIED;
    }
    close(enable_f);
    return MRAA_SUCCESS;
}

static mraa_aio_context
mraa_aio_init_internal(mraa_adv_func_t* func_table, int aio)
{
    mraa_aio_context dev = calloc(1, sizeof(struct _aio));
    if (dev == NULL) {
        return NULL;
    }
    dev->advance_func = func_table;

    if (IS_FUNC_DEFINED(dev, aio_init_internal_replace)) {
        if (dev->advance_func->aio_init_internal_replace(dev, aio) == MRAA_SUCCESS) {
            return dev;
        }
        free(dev);
        return NULL;
    }

    // Open valid  analog input file and get the pointer.
    if (MRAA_SUCCESS != aio_get_valid_fp(dev)) {
        free(dev);
        return NULL;
    }

    return dev;
}

static mraa_result_t
aio_get_valid_fp(mraa_aio_context dev)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "aio: get_valid_fp: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, aio_get_valid_fp)) {
        return dev->advance_func->aio_get_valid_fp(dev);
    }

    char file_path[64] = "";

    // Open file Analog device input channel raw voltage file for reading.
    snprintf(file_path, 64, "/sys/bus/iio/devices/iio:device0/in_voltage%d_raw", dev->channel);

    dev->adc_in_fp = open(file_path, O_RDONLY);
    if (dev->adc_in_fp == -1) {
        syslog(LOG_ERR, "aio: Failed to open input raw file %s for reading!", file_path);
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    return MRAA_SUCCESS;
}

mraa_result_t
mraa_pwm_enable(mraa_pwm_context dev, int enable)
{
	if (IS_FUNC_DEFINED(dev, pwm_enable_replace)) {
        return dev->advance_func->pwm_enable_replace(dev, enable);
    }
    int status;
    if (enable != 0) {
        status = 1;
    } else {
        status = enable;
    }
    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);

    int enable_f = open(bu, O_RDWR);

    if (enable_f == -1) {
        syslog(LOG_ERR, "pwm: Failed to open enable for writing");
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[2];
    int size = snprintf(out, sizeof(out), "%d", enable);
    if (write(enable_f, out, size * sizeof(char)) == -1) {
        syslog(LOG_ERR, "pwm: Failed to write to enable");
        close(enable_f);
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    close(enable_f);
    return MRAA_SUCCESS;
}

static int
mraa_pwm_read_duty(mraa_pwm_context dev)
{
	if (IS_FUNC_DEFINED(dev, pwm_read_duty_replace)) {
        return dev->advance_func->pwm_read_duty_replace(dev);
    }
    if (dev->duty_fp == -1) {
        if (mraa_pwm_setup_duty_fp(dev) == 1) {
            return MRAA_ERROR_INVALID_HANDLE;
        }
    } else {
        lseek(dev->duty_fp, 0, SEEK_SET);
    }
    off_t size = lseek(dev->duty_fp, 0, SEEK_END);
    lseek(dev->duty_fp, 0, SEEK_SET);
    char output[MAX_SIZE];
    ssize_t rb = read(dev->duty_fp, output, size + 1);
    if (rb < 0) {
        syslog(LOG_ERR, "pwm: Error in reading duty");
        return -1;
    }

    char* endptr;
    long int ret = strtol(output, &endptr, 10);
    if ('\0' != *endptr && '\n' != *endptr) {
        syslog(LOG_ERR, "pwm: Error in string converstion");
        return -1;
    } else if (ret > INT_MAX || ret < INT_MIN) {
        syslog(LOG_ERR, "pwm: Number is invalid");
        return -1;
    }
    return (int) ret;
}

mraa_result_t
mraa_uart_set_non_blocking(mraa_uart_context dev, mraa_boolean_t nonblock)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: non_blocking: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_non_blocking_replace)) {
        return dev->advance_func->uart_set_non_blocking_replace(dev, nonblock);
    }

    // get current flags
    int flags = fcntl(dev->fd, F_GETFL);

    // update flags with new blocking state according to nonblock bool
    if (nonblock) {
        flags |= O_NONBLOCK;
    } else {
        flags &= ~O_NONBLOCK;
    }

    // set new flags
    if (fcntl(dev->fd, F_SETFL, flags) < 0) {
        syslog(LOG_ERR, "uart%i: non_blocking: failed changing fd blocking state: %s", dev->index, strerror(errno));
        return MRAA_ERROR_UNSPECIFIED;
    }

    return MRAA_SUCCESS;
}

mraa_result_t
mraa_uart_set_timeout(mraa_uart_context dev, int read, int write, int interchar)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: set_timeout: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_timeout_replace)) {
        return dev->advance_func->uart_set_timeout_replace(dev, read, write, interchar);
    }

    struct termios termio;
    // get current modes
    if (tcgetattr(dev->fd, &termio)) {
        syslog(LOG_ERR, "uart%i: set_timeout: tcgetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    if (read > 0) {
        read = read / 100;
        if (read == 0)
            read = 1;
    }
    termio.c_lflag &= ~ICANON; /* Set non-canonical mode */
    termio.c_cc[VTIME] = read; /* Set timeout in tenth seconds */
    if (tcsetattr(dev->fd, TCSANOW, &termio) < 0) {
        syslog(LOG_ERR, "uart%i: set_timeout: tcsetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
    }

    return MRAA_SUCCESS;
}

mraa_gpio_context
mraa_gpio_init(int pin)
{
    mraa_board_t* board = plat;

    if (board == NULL) {
        syslog(LOG_ERR, "gpio%i: init: platform not initialised", pin);
        return NULL;
    }

    if (mraa_is_sub_platform_id(pin)) {
        syslog(LOG_NOTICE, "gpio%i: init: Using sub platform", pin);
        board = board->sub_platform;
        if (board == NULL) {
            syslog(LOG_ERR, "gpio%i: init: Sub platform not initialised", pin);
            return NULL;
        }
        pin = mraa_get_sub_platform_index(pin);
    }

    if (board->chardev_capable) {
        int pins[1] = { pin };
        return mraa_gpio_init_multi(pins, 1);
    }

    if (pin < 0 || pin >= board->phy_pin_count) {
        syslog(LOG_ERR, "gpio: init: pin %i beyond platform pin count (%i)",
               pin, board->phy_pin_count);
        return NULL;
    }
    if (board->pins[pin].capabilities.gpio != 1) {
        syslog(LOG_ERR, "gpio: init: pin %i not capable of gpio", pin);
        return NULL;
    }
    if (board->pins[pin].gpio.mux_total > 0) {
        if (mraa_setup_mux_mapped(board->pins[pin].gpio) != MRAA_SUCCESS) {
            syslog(LOG_ERR, "gpio%i: init: unable to setup muxes", pin);
            return NULL;
        }
    }

    mraa_gpio_context r = mraa_gpio_init_internal(board->adv_func, board->pins[pin].gpio.pinmap);

    if (r == NULL) {
        return NULL;
    }

    if (r->phy_pin == -1)
        r->phy_pin = pin;

    if (IS_FUNC_DEFINED(r, gpio_init_post)) {
        mraa_result_t ret = r->advance_func->gpio_init_post(r);
        if (ret != MRAA_SUCCESS) {
            free(r);
            return NULL;
        }
    }

    return r;
}

mraa_result_t
mraa_spi_frequency(mraa_spi_context dev, int hz)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "spi: frequency: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, spi_frequency_replace)) {
        return dev->advance_func->spi_frequency_replace(dev, hz);
    }

    int speed = 0;
    dev->clock = hz;
    if (ioctl(dev->devfd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) != -1) {
	if (speed < hz) {
            // We wanted to never go higher than SPI_IOC_RD_MAX_SPEED_HZ but it
            // seems a bunch of drivers don't have this set to the actual max
            // so we only complain about it
            // dev->clock = speed;
            syslog(LOG_NOTICE, "spi: Selected speed (%d Hz) is higher than the kernel max allowed speed (%lu Hz)", hz, SPI_IOC_RD_MAX_SPEED_HZ);
        }
    }
    return MRAA_SUCCESS;
}

static mraa_result_t
mraa_pwm_write_duty(mraa_pwm_context dev, int duty)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: write_duty: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_write_replace)) {
        return dev->advance_func->pwm_write_replace(dev, duty);
    }
    if (dev->duty_fp == -1) {
        if (mraa_pwm_setup_duty_fp(dev) == 1) {
            syslog(LOG_ERR, "pwm%i write_duty: Failed to open duty_cycle for writing: %s", dev->pin, strerror(errno));
            return MRAA_ERROR_INVALID_RESOURCE;
        }
    }
    char bu[64];
    int length = sprintf(bu, "%d", duty);
    if (write(dev->duty_fp, bu, length * sizeof(char)) == -1)
    {
        syslog(LOG_ERR, "pwm%i write_duty: Failed to write to duty_cycle: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    return MRAA_SUCCESS;
}

static mraa_result_t
mraa_pwm_write_period(mraa_pwm_context dev, int period)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: write_period: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_period_replace)) {
        mraa_result_t result = dev->advance_func->pwm_period_replace(dev, period);
        if (result == MRAA_SUCCESS) {
            dev->period = period;
        }
        return result;
    }
    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/period", dev->chipid, dev->pin);

    int period_f = open(bu, O_RDWR);
    if (period_f == -1) {
        syslog(LOG_ERR, "pwm%i write_period: Failed to open period for writing: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[MAX_SIZE];
    int length = snprintf(out, MAX_SIZE, "%d", period);
    if (write(period_f, out, length * sizeof(char)) == -1) {
        close(period_f);
        syslog(LOG_ERR, "pwm%i write_period: Failed to write to period: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    close(period_f);
    dev->period = period;
    return MRAA_SUCCESS;
}

mraa_result_t
mraa_uart_set_baudrate(mraa_uart_context dev, unsigned int baud)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: set_baudrate: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_baudrate_replace)) {
        return dev->advance_func->uart_set_baudrate_replace(dev, baud);
    }

    struct termios termio;
    if (tcgetattr(dev->fd, &termio)) {
        syslog(LOG_ERR, "uart%i: set_baudrate: tcgetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    // set our baud rates
    speed_t speed = uint2speed(baud);
    if (speed == B0)
    {
        syslog(LOG_ERR, "uart%i: set_baudrate: invalid baudrate: %i", dev->index, baud);
        return MRAA_ERROR_INVALID_PARAMETER;
    }
    cfsetispeed(&termio, speed);
    cfsetospeed(&termio, speed);

    // make it so
    if (tcsetattr(dev->fd, TCSAFLUSH, &termio) < 0) {
        syslog(LOG_ERR, "uart%i: set_baudrate: tcsetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
    }
    return MRAA_SUCCESS;
}