UInput Event Injector (Inject Event into Android via kernel)

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <linux/input.h>
#include <linux/uinput.h>

#define die(str, args...) do { \
        perror(str); \
        exit(EXIT_FAILURE); \
    } while(0)

static void send_event(int fd, uint16_t type, uint16_t code, int32_t value) {
    struct input_event event;
    int err;

    memset(&event, 0, sizeof(event));

    event.type = type;
    event.code = code;
    event.value = value;
    gettimeofday(&event.time, NULL);
    if (write(fd, &event, sizeof(event)) < 0) {
        die("event sent error: %s", strerror(errno));
    }
}

int main()
{
    int fd;
    struct uinput_user_dev uidev;
    int i;
    uint16_t type, code;
    int32_t value;

    fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
    if (fd < 0)
        die("error: open");

    // Keyboard
    if (ioctl(fd, UI_SET_EVBIT, EV_KEY) < 0)
        die("error: ioctl");

    for (i = 0; i < 256; i++) {
        if (ioctl(fd, UI_SET_KEYBIT, i) < 0)
            die("error: ioctl");   
    }

    // Mouse
    if (ioctl(fd, UI_SET_EVBIT, EV_REL) < 0)
        die("error: ioctl");
    if (ioctl(fd, UI_SET_RELBIT, REL_X) < 0)
        die("error: ioctl");
    if (ioctl(fd, UI_SET_RELBIT, REL_Y) < 0)
        die("error: ioctl");

    for (i = BTN_LEFT; i <= BTN_TASK; i++) {
        if (ioctl(fd, UI_SET_KEYBIT, i) < 0)
            die("error: ioctl");   
    }

    memset(&uidev, 0, sizeof(uidev));
    snprintf(uidev.name, UINPUT_MAX_NAME_SIZE, "Input Injector");
    uidev.id.bustype = BUS_VIRTUAL;
    uidev.id.vendor  = 0;
    uidev.id.product = 0;
    uidev.id.version = 0;

    if (write(fd, &uidev, sizeof(uidev)) < 0)
        die("error: write");

    if (ioctl(fd, UI_DEV_CREATE) < 0)
        die("error: ioctl");

    do {
        scanf("%hu %hu %d", &type, &code, &value);
        send_event(fd, type, code, value);
    } while (type != 65535);

    if (ioctl(fd, UI_DEV_DESTROY) < 0)
        die("error: ioctl");

    close(fd);

    return 0;
}