git.itanic.dy.fi Git - log-plotter/blob - main.c

   1 #include <stdio.h>
   2 #include <unistd.h>
   3 #include <fcntl.h>
   4 #include <sys/epoll.h>
   5 #include <sys/types.h>
   6 #include <sys/stat.h>
   7
   8 #include "options.h"
   9 #include "baud.h"
  10 #include "debug.h"
  11
  12 int read_data(int infd, int outfd)
  13 {
  14         struct epoll_event ev;
  15         int epoll_fd;
  16         int ret;
  17         char buf[256];
  18
  19         epoll_fd = epoll_create(1);
  20         if (epoll_fd < 0) {
  21                 pr_err("Failed to create epoll socket: %m\n");
  22                 return -1;
  23         }
  24
  25         ev.events = EPOLLIN;
  26         ev.data.fd = infd;
  27         if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, infd, &ev) == -1) {
  28                 pr_err("epoll_ctl: %m\n");
  29                 return 1;
  30         }
  31
  32         while (1) {
  33                 ret = epoll_wait(epoll_fd, &ev, 1, -1);
  34                 if (ret == 0)
  35                         continue;
  36
  37                 if (ret < 0) {
  38                         pr_err("epoll: %m\n");
  39                         return -1;
  40                 }
  41
  42                 ret = read(infd, buf, sizeof(buf));
  43                 if (read < 0) {
  44                         pr_err("read: %m\n");
  45                         break;
  46                 }
  47
  48                 if (ret == 0) {
  49                         pr_err("Read EOF, stopping\n");
  50                         break;
  51                 }
  52
  53                 ret = write(outfd, buf, ret);
  54                 if (read < 0) {
  55                         pr_err("write: %m\n");
  56                         break;
  57                 }
  58         }
  59
  60         return 0;
  61 }
  62
  63 int main(int argc, char *argv[])
  64 {
  65         struct plotter_options options;
  66         int fd, baud, ret = 0, out_fd = STDOUT_FILENO;
  67
  68         if (read_args(argc, argv, &options))
  69                 return 1;
  70
  71         baud = options.baud_rate;
  72         fd = open_at_baud(options.device_path, &baud);
  73         if (fd < 0)
  74                 return 1;
  75
  76         if (baud != options.baud_rate) {
  77                 pr_err("Failed to set baudrate to %d, only got %d\n",
  78                         options.baud_rate, baud);
  79                 ret = 1;
  80                 goto out;
  81         }
  82
  83         if (options.output_path) {
  84                 pr_debug("Opening %s for writing the log file\n",
  85                         options.output_path);
  86
  87                 out_fd = open(options.output_path,
  88                         O_CREAT | O_APPEND | O_WRONLY, 0664);
  89                 if (out_fd < 0) {
  90                         pr_err("Failed to open file %s for writing: %m\n",
  91                                 options.output_path);
  92                         ret = 1;
  93                         goto out;
  94                 }
  95         }
  96
  97         read_data(fd, out_fd);
  98
  99 out:
 100         close(fd);
 101         return ret;
 102 }