main.c

linux下tftp客气端的源码实现

    {
      putusage (argv[0]);
      return;
    }
  targ = argv[argc - 1];
  if (strchr (argv[argc - 1], ':'))
    {
      char *cp;

      for (n = 1; n < argc - 1; n++)
	if (strchr (argv[n], ':'))
	  {
	    putusage (argv[0]);
	    return;
	  }
      cp = argv[argc - 1];
      targ = strchr (cp, ':');
      *targ++ = 0;
      if (resolve_name (cp, 0) != RESOLVE_OK)
	return;
    }
  if (!connected)
    {
      printf ("No target machine specified.\n");
      return;
    }
  if (argc < 4)
    {
      cp = argc == 2 ? tail (targ) : argv[1];
      fd = open (cp, O_RDONLY);
      if (fd < 0)
	{
	  fprintf (stderr, "tftp: ");
	  perror (cp);
	  return;
	}
      if (verbose)
	printf ("putting %s to %s:%s [%s]\n", cp, hostname, targ, mode);
      peeraddr.sin_port = port ? port : sp->s_port;
      send_file (fd, targ, mode);
      return;
    }
  /* this assumes the target is a directory */
  /* on a remote unix system.  hmmmm.  */
  cp = strchr (targ, '\0');
  *cp++ = '/';
  for (n = 1; n < argc - 1; n++)
    {
      strcpy (cp, tail (argv[n]));
      fd = open (argv[n], O_RDONLY);
      if (fd < 0)
	{
	  fprintf (stderr, "tftp: ");
	  perror (argv[n]);
	  continue;
	}
      if (verbose)
	printf ("putting %s to %s:%s [%s]\n", argv[n], hostname, targ, mode);
      peeraddr.sin_port = port ? port : sp->s_port;
      send_file (fd, targ, mode);
    }
}

static void
putusage (char *s)
{
  printf ("usage: %s file ... host:target, or\n", s);
  printf ("       %s file ... target (when already connected)\n", s);
}

/*
 * Receive file(s).
 */
void
get (int argc, char *argv[])
{
  int             fd;
  register int    n;
  register char  *cp;
  char           *src;

  if (argc < 2)
    get_args ("get", "(files) ", &argc, &argv);

  if (argc < 2)
    {
      getusage (argv[0]);
      return;
    }
  if (!connected)
    {
      for (n = 1; n < argc; n++)
	if (strchr (argv[n], ':') == 0)
	  {
	    getusage (argv[0]);
	    return;
	  }
    }
  for (n = 1; n < argc; n++)
    {
      src = strchr (argv[n], ':');
      if (src == NULL)
	src = argv[n];
      else
	{
	  *src++ = 0;
	  if (resolve_name (argv[n], 0) != RESOLVE_OK)
	    continue;
	}
      
      if (argc < 4)
	{
	  cp = argc == 3 ? argv[2] : tail (src);
	  fd = creat (cp, 0644);
	  if (fd < 0)
	    {
	      fprintf (stderr, "tftp: ");
	      perror (cp);
	      return;
	    }
	  if (verbose)
	    printf ("getting from %s:%s to %s [%s]\n",
		    hostname, src, cp, mode);
	  peeraddr.sin_port = port ? port : sp->s_port;
	  recvfile (fd, src, mode);
	  break;
	}
      cp = tail (src);		/* new .. jdg */
      fd = creat (cp, 0644);
      if (fd < 0)
	{
	  fprintf (stderr, "tftp: ");
	  perror (cp);
	  continue;
	}
      if (verbose)
	printf ("getting from %s:%s to %s [%s]\n", hostname, src, cp, mode);
      peeraddr.sin_port = port ? port : sp->s_port;
      recvfile (fd, src, mode);
    }
}

static void
getusage (char *s)
{
  printf ("usage: %s host:file host:file ... file, or\n", s);
  printf ("       %s file file ... file if connected\n", s);
}

int rexmtval = TIMEOUT;

void
setrexmt (int argc, char *argv[])
{
  int t;

  if (argc < 2)
    get_args ("Rexmt-timeout", "(value) ", &argc, &argv);

  if (argc != 2)
    {
      printf ("usage: %s value\n", argv[0]);
      return;
    }
  t = atoi (argv[1]);
  if (t < 0)
    printf ("%s: bad value\n", argv[1]);
  else
    rexmtval = t;
}

int maxtimeout = 5 * TIMEOUT;

void
settimeout (int argc, char *argv[])
{
  int t;

  if (argc < 2)
    get_args ("Maximum-timeout", "(value) ", &argc, &argv);

  if (argc != 2)
    {
      printf ("usage: %s value\n", argv[0]);
      return;
    }
  t = atoi (argv[1]);
  if (t < 0)
    printf ("%s: bad value\n", argv[1]);
  else
    maxtimeout = t;
}

void
status (int argc, char *argv[])
{
  if (connected)
    printf ("Connected to %s.\n", hostname);
  else
    printf ("Not connected.\n");
  printf ("Mode: %s Verbose: %s Tracing: %s\n", mode,
	  verbose ? "on" : "off", trace ? "on" : "off");
  printf ("Rexmt-interval: %d seconds, Max-timeout: %d seconds\n",
	  rexmtval, maxtimeout);
}

void
intr ()
{
  signal (SIGALRM, SIG_IGN);
  alarm (0);
  longjmp (toplevel, -1);
}

char *
tail (char *filename)
{
  register char  *s;

  while (*filename)
    {
      s = strrchr (filename, '/');
      if (s == NULL)
	break;
      if (s[1])
	return (s + 1);
      *s = '\0';
    }
  return filename;
}

/*
 * Command parser.
 */
static void
command ()
{
  register struct cmd *c;

  for (;;)
    {
      printf ("%s> ", prompt);
      if (fgets (line, sizeof line, stdin) == 0)
	{
	  if (feof (stdin))
	    exit (0);
	  else
	    continue;
	}
      if (line[0] == 0)
	continue;
      makeargv ();
      if (margc == 0)
	continue;
      c = getcmd (margv[0]);
      if (c == (struct cmd *) -1)
	{
	  printf ("?Ambiguous command\n");
	  continue;
	}
      if (c == 0)
	{
	  printf ("?Invalid command\n");
	  continue;
	}
      (*c->handler) (margc, margv);
    }
}

struct cmd *
getcmd (register char *name)
{
  register char  *p, *q;
  register struct cmd *c, *found;
  register int nmatches, longest;

  longest = 0;
  nmatches = 0;
  found = 0;
  for (c = cmdtab; (p = c->name) != NULL; c++)
    {
      for (q = name; *q == *p++; q++)
	if (*q == 0)		/* exact match? */
	  return (c);
      
      if (!*q)
	{			/* the name was a prefix */
	  if (q - name > longest)
	    {
	      longest = q - name;
	      nmatches = 1;
	      found = c;
	    }
	  else if (q - name == longest)
	    nmatches++;
	}
    }
  if (nmatches > 1)
    return (struct cmd *) -1;
  return found;
}

/*
 * Slice a string up into argc/argv.
 */
static void
makeargv ()
{
  register char  *cp;
  register char **argp = margv;

  margc = 0;
  for (cp = line; *cp;)
    {
      while (isspace (*cp))
	cp++;
      if (*cp == '\0')
	break;
      *argp++ = cp;
      margc += 1;
      while (*cp != '\0' && !isspace (*cp))
	cp++;
      if (*cp == '\0')
	break;
      *cp++ = '\0';
    }
  *argp++ = 0;
}

void
quit (int argc, char *argv[])
{
  exit (0);
}

/*
 * Help command.
 */
void
help (int argc, char *argv[])
{
  register struct cmd *c;

  if (argc == 1)
    {
      printf ("Commands may be abbreviated.  Commands are:\n\n");
      for (c = cmdtab; c->name; c++)
	printf ("%-*s\t%s\n", (int) HELPINDENT, c->name, c->help);
      return;
    }
  
  while (--argc > 0)
    {
      register char  *arg;

      arg = *++argv;
      c = getcmd (arg);
      if (c == (struct cmd *) -1)
	printf ("?Ambiguous help command %s\n", arg);
      else if (c == (struct cmd *) 0)
	printf ("?Invalid help command %s\n", arg);
      else
	printf ("%s\n", c->help);
    }
}

void
settrace (int argc, char **argv)
{
  trace = !trace;
  printf ("Packet tracing %s.\n", trace ? "on" : "off");
}

void
setverbose (int argc, char **argv)
{
  verbose = !verbose;
  printf ("Verbose mode %s.\n", verbose ? "on" : "off");
}