linux-kernel/fake-serial/user-land/fstool.c

   1 #include <stdio.h>
   2 #include <sys/types.h>
   3 #include <sys/stat.h>
   4 #include <fcntl.h>
   5 #include <termios.h>
   6 #include <unistd.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <errno.h>
  10
  11 #define NOT_USED(x)  (x = x)
  12
  13 struct termios original;
  14
  15 /**
  16  * close_serial_port - Close a serial port
  17  *
  18  * @param: the port to be closed
  19  *
  20  * Close the specified serial port and sets the
  21  * its termios structure to the default settings.
  22  */
  23 static void close_serial_port(int fd)
  24 {
  25         tcsetattr(fd, TCSANOW, &original);
  26         close(fd);
  27 }
  28
  29 /**
  30  * open_serial_port - Open a serial port
  31  *
  32  * @param port: the port to be opened
  33  *
  34  * @return On success a file descriptor,
  35  * -1 otherwise
  36  */
  37 static int open_serial_port(const char *port)
  38 {
  39         int fd, ret;
  40         struct termios tio;
  41
  42         if (!port) {
  43                 errno = EINVAL;
  44                 return -1;
  45         }
  46
  47         fd = open(port, O_RDWR | O_NOCTTY);
  48         if (fd < 0)
  49                 goto out;
  50
  51         ret = tcgetattr(fd, &original);
  52         if (ret < 0)
  53                 goto err_out;
  54
  55         memset(&tio, 0, sizeof(struct termios));
  56         tio.c_cflag = CS8 | CREAD | CRTSCTS | CLOCAL | HUPCL;
  57         tio.c_iflag = IGNPAR | IGNBRK;
  58         tio.c_oflag = 0;
  59         tio.c_lflag = 0;
  60         tio.c_cc[VTIME] = 1;
  61         tio.c_cc[VMIN] = 0;
  62
  63         /* If it fails, we will use default settings. */
  64         cfsetispeed(&tio, B115200);
  65         cfsetospeed(&tio, B115200);
  66
  67         ret = tcflush(fd, TCIFLUSH);
  68         if (ret < 0)
  69                 goto err_out;
  70
  71         ret = tcsetattr(fd, TCSANOW, &tio);
  72         if (ret)
  73                 goto err_out;
  74
  75  out:
  76         return fd;
  77  err_out:
  78         close(fd);
  79         fd = -1;
  80         goto out;
  81 }
  82
  83 int main(int argc, char *argv[])
  84 {
  85         int i, fd;
  86         size_t count;
  87         ssize_t bytes;
  88         char *cmd, *p, buf[128];
  89
  90         NOT_USED(argc);
  91
  92         cmd = argv[2];
  93         if (!cmd) {
  94                 fprintf(stderr, "No cmd.\n");
  95                 exit(1);
  96         }
  97
  98         fd = open_serial_port(argv[1]);
  99         if (fd < -1) {
 100                 perror("open()");
 101                 exit(1);
 102         }
 103
 104         for (i = 0; i < (int) strlen(cmd); i++) {
 105
 106                 bytes = write(fd, &cmd[i], (size_t) 1);
 107                 if (bytes < 0) {
 108                         perror("write()");
 109                         exit(1);
 110                 } else if (bytes != 1) {
 111                         fprintf(stderr, "Warning wrote %d instead of 1\n", bytes);
 112                 }
 113         }
 114
 115         p = buf;
 116         count = sizeof(buf);
 117         memset(p, '\0', count);
 118         bytes = 1;
 119
 120         while ((p - buf) < (unsigned int) sizeof(buf) && !strchr(buf, '%')) {
 121                 bytes = read(fd, p, count);
 122                 if (bytes < 0) {
 123                         perror("read()");
 124                         exit(1);
 125                 }
 126
 127                 p += bytes;
 128                 count -= bytes;
 129         }
 130         close_serial_port(fd);
 131
 132         printf("%s\n", buf);
 133         return 0;
 134 }