mavlink_shell.h

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/**
 * @file mavlink_shell.h
 * A shell to be used via MAVLink
 *
 * @author Beat Küng <beat-kueng@gmx.net>
 */


#include <stddef.h>
#include <stdint.h>
#include <px4_platform_common/tasks.h>

#pragma once

class MavlinkShell
{
public:
    MavlinkShell() = default;

    ~MavlinkShell();

    /**
     * Start the mavlink shell.
     *
     * @return      0 on success.
     */
    int     start();

    /**
     * Write to the shell
     * @return number of written bytes
     */
    size_t write(uint8_t *buffer, size_t len);

    /**
     * Read from the shell. This is blocking, if 0 bytes are available, this will block.
     * @param len buffer length
     * @return number of bytes read.
     */
    size_t read(uint8_t *buffer, size_t len);

    /**
     * Get the number of bytes that can be read.
     */
    size_t available();

private:

    int _to_shell_fd = -1; /** fd to write to the shell */
    int _from_shell_fd = -1; /** fd to read from the shell */
    int _shell_fds[2] = { -1, -1}; /** stdin & out used by the shell */
    px4_task_t _task;

    static int shell_start_thread(int argc, char *argv[]);

    /* do not allow copying this class */
    MavlinkShell(const MavlinkShell &) = delete;
    MavlinkShell operator=(const MavlinkShell &) = delete;
};