簡易版 Minicom

昨天坐車下南部，在車上心血來潮想在 NEO1973上玩Minicom 結果發現手上沒有 minicom的 package。人在車上又沒有網路…想玩東西又沒得玩…就自已寫嘍…
然後就在車上開始 coding ...
發現還蠻有趣的，大概到台中的時候完成，之後就在車上一直玩…
玩到 Notebook 沒電 @_@ 4 cell 的電池果然是不夠力啊

執行檔是 tickminicom
使用方法是 ./tickminicom [device] [speed]
default 的 device 是 /dev/ttySAC0 ，speed 是 115200
跳脫字元是 '%'

因為是自已寫的，所以可以很直接的測試幾個想知道的性質…

Filename: Makefile

---

CC=arm-angstrom-linux-gnueabi-gcc
all:
  $(CC) -o tickminicom tick_minicom.c util.c
  gcc -o tickminicom_x86 tick_minicom.c util.c

Filename: debug.h

---

#ifndef __MPENV_DEBUG_H__
#define __MPENV_DEBUG_H__

#include <assert.h>

#define CONFIG_DEBUG

#ifdef CONFIG_DEBUG
 #include <stdio.h>
 #define debug(f, a...)                                             \
do{                                                             \
  printf ("DEBUG: (%s, %d): %s: ",__FILE__, __LINE__, __FUNCTION__);      \
  printf (f, ## a);                               \
} while (0)
 #else
    #define debug(f, a...)
#endif

#define error(f, a...)                                             \
do{                                                             \
  printf ("ERROR: (%s, %d): %s: ",__FILE__, __LINE__, __FUNCTION__);      \
  printf (f, ## a);                               \
} while (0)


#endif

Filename: util.h

---

#ifndef __TICK_MINICOM_UTIL_H__
#define __TICK_MINICOM_UTIL_H__

#include <termios.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>

/// Be aware 'x' cannot be a expression or this function cause unpredicable result.
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

struct bdrt {
int bps;
u_int32_t b;
};

static struct bdrt bdrts[] = {
  { 0, B0 },
  { 9600, B9600 },
  { 19200, B19200 },
  { 38400, B38400 },
  { 57600, B57600 },
  { 115200, B115200 },
  { 230400, B230400 },
  { 460800, B460800 },
  { 921600, B921600 },
};

int getche(int fd);

int open_device(char *device,int speed);

int set_baud(int fd,int rate);

#endif

Filename: util.c

---

#include "util.h"
#include "debug.h"
#include <string.h>

int getche (int fd) {
  int i;
  char ch;
  struct termios old, new;
  tcgetattr (fd, &old);
  memcpy (&new,&old, sizeof (struct termios));
  new.c_lflag = ~(ICANON | ECHO);
  tcsetattr (fd, TCSANOW,&new);
  i = read (fd,&ch, 1);
  tcsetattr (fd, TCSANOW, &old);
  if (i == 1) {
          return ch;
  }
  else {
      debug("fd %d ERROR\n",fd);
      return -1;
  }
}

int set_baud(int fd,int rate) {
int i,rt;
u_int32_t bd = 0;
struct termios ti;
for (i = 0; i < ARRAY_SIZE(bdrts); i++) {
  if (bdrts[i].bps == rate) {
      bd = bdrts[i].b;
      break;
  }
}
if (bd==0) {
  error("Cannot set Baud Rate!!\n");
  return -1;
}
rt = tcgetattr(fd, &ti);
if (rt<0) {
  error ("Cannot get attr i=%d\n",rt);
  return rt;
}
rt = cfsetispeed(&ti, B0);
if (rt<0) {
  error("Cannot set input baud to B0!!\n");
  return rt;
}
debug("Open uart with speed %d\n",bdrts[i].bps);
rt = cfsetospeed(&ti, bd);
if (rt < 0) {
  error("Cannot set baud rate %d\n",bdrts[i].bps);
  return rt;
}
ti.c_cflag |= CRTSCTS;  // hardware control
return tcsetattr(fd, 0, &ti);
}

/**
* Open Uart for testing
* return value is the fd
*/
int  open_device (char *device,int speed) {
int fd;
if (device==NULL) {
  error("device is invalid (NULL pointer)\n");
  return -1;
}
debug("Try to open device %s!\n",device);
fd = open(device,O_RDWR);
if (fd < 0) {
  error("cannot open uart %s, fd is %d\n",device,fd);
  error("%s\n",strerror(errno));
  return -1;
}
if (set_baud(fd,speed) < 0)  {
  error("Set Baud rate failed!!\n");
  return -1;
}
return fd;
}

Filename: tick_minicom.c

---

/**
* @file tick_minicom.c
* @brief a tiny uart client
* @license GPL (General Public License)
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include "debug.h"
#include "util.h"

#define DEFAULT_UART "/dev/ttySAC0"
#define DEFAULT_BAUD 115200

static int keep_run=1;



/// Set '%' as the escape code
void input_command(int input,int output)  {
int i;
char buf[1];
while(keep_run)  {
  i=getche(input);
  if (i< 0) {
      debug("file closed!!\n");
      keep_run=0;
      break;
  }
  if (i=='%') {
      debug("User entered the escape code.\n");
      debug("Exiting program!\n");
      keep_run=0;
      break;
  }
  buf[0]=i;
  write(output,buf,1);
}
}

void read_from_uart(int input,int output) {
int i;
char buf[1];
while (keep_run) {
  i=getche(input);
  buf[0]=i;
  i=write(output,buf,1);
}
}

int main (int args,char **argv) {
int uart;
int pid;
char buf[128];
if (args==1) {
  uart=open_device(DEFAULT_UART,DEFAULT_BAUD);
} else if (args==2) {
  uart=open_device(argv[1],DEFAULT_BAUD);
} else {
  uart=open_device(argv[1],atoi(argv[2]));
}
if (uart<0) {
  error("Open device failed !!\n");
  return 0;
}else {
  debug("Open Uart and set baud rate OK!!\n");
}
keep_run=1;
pid=fork();
if (pid) {  // parent
  input_command(0,uart);
  debug("Exiting Tick's minicom\n");
}else {  // child
  pid = getppid();
  read_from_uart(uart,1);
  debug("Try to close uart\n");
  debug("Result of close uart=%d\n",close(uart));
}
sprintf(buf,"kill -9 %d",pid);
system(buf);
}