command.c

   1 /* $OpenBSD: command.c,v 1.12 2012/07/15 06:55:28 nicm Exp $ */
   2
   3 /*
   4  * Copyright (c) 2012 Nicholas Marriott <nicm@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/types.h>
  20 #include <sys/ioctl.h>
  21 #include <sys/wait.h>
  22
  23 #include <event.h>
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <limits.h>
  27 #include <paths.h>
  28 #include <signal.h>
  29 #include <stdlib.h>
  30 #include <stdio.h>
  31 #include <unistd.h>
  32
  33 #include "cu.h"
  34
  35 /* OpenBSD implementation of closeret() returns int,
  36    while FreeBSD and Linux libbsd are void instead */
  37 //#define CLOSEFROM_INTRET 1
  38
  39 /* closefrom() is implemented in bsd.c */
  40 #if CLOSEFROM_INTRET
  41 int
  42 #else
  43 void
  44 #endif
  45 closefrom(int start);
  46
  47 void    pipe_command(void);
  48 void    connect_command(void);
  49 void    send_file(void);
  50 void    send_xmodem(void);
  51
  52 void
  53 pipe_command(void)
  54 {
  55         const char      *cmd;
  56         pid_t            pid;
  57         int              fd;
  58
  59         cmd = get_input("Local command?");
  60         if (cmd == NULL || *cmd == '\0')
  61                 return;
  62
  63         restore_termios();
  64
  65         switch (pid = fork()) {
  66         case -1:
  67                 cu_err(1, "fork");
  68                 _exit(1);
  69         case 0:
  70                 fd = open(_PATH_DEVNULL, O_RDWR);
  71                 if (fd < 0 || dup2(fd, STDIN_FILENO) == -1)
  72                         _exit(1);
  73                 close(fd);
  74
  75                 if (signal(SIGINT, SIG_DFL) == SIG_ERR)
  76                         _exit(1);
  77                 if (signal(SIGQUIT, SIG_DFL) == SIG_ERR)
  78                         _exit(1);
  79
  80                 /* attach stdout to line */
  81                 if (dup2(line_fd, STDOUT_FILENO) == -1)
  82                         _exit(1);
  83
  84 #if CLOSEFROM_INTRET
  85                 if (
  86 #endif
  87                         closefrom(STDERR_FILENO + 1)
  88 #if CLOSEFROM_INTRET
  89                         != 0)
  90                         _exit(1)
  91 #endif
  92                           ;
  93
  94                 execl(_PATH_BSHELL, "sh", "-c", cmd, (void*)NULL);
  95                 _exit(1);
  96         default:
  97                 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
  98                         /* nothing */;
  99                 break;
 100         }
 101
 102         set_termios();
 103 }
 104
 105 void
 106 connect_command(void)
 107 {
 108         const char      *cmd;
 109         pid_t            pid;
 110
 111         /*
 112          * Fork a program with:
 113          *  0 <-> remote tty in
 114          *  1 <-> remote tty out
 115          *  2 <-> local tty stderr
 116          */
 117
 118         cmd = get_input("Local command?");
 119         if (cmd == NULL || *cmd == '\0')
 120                 return;
 121
 122         restore_termios();
 123
 124         switch (pid = fork()) {
 125         case -1:
 126                 cu_err(1, "fork");
 127                 _exit(1);
 128         case 0:
 129                 if (signal(SIGINT, SIG_DFL) == SIG_ERR)
 130                         _exit(1);
 131                 if (signal(SIGQUIT, SIG_DFL) == SIG_ERR)
 132                         _exit(1);
 133
 134                 /* attach stdout and stdin to line */
 135                 if (dup2(line_fd, STDOUT_FILENO) == -1)
 136                         _exit(1);
 137                 if (dup2(line_fd, STDIN_FILENO) == -1)
 138                         _exit(1);
 139
 140 #if CLOSEFROM_INTRET
 141                 if (
 142 #endif
 143                         closefrom(STDERR_FILENO + 1)
 144 #if CLOSEFROM_INTRET
 145                         != 0)
 146                         _exit(1)
 147 #endif
 148                           ;
 149
 150                 execl(_PATH_BSHELL, "sh", "-c", cmd, (void*)NULL);
 151                 _exit(1);
 152         default:
 153                 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
 154                         /* nothing */;
 155                 break;
 156         }
 157
 158         set_termios();
 159 }
 160
 161 void
 162 send_file(void)
 163 {
 164         const char      *file;
 165         FILE            *f;
 166         char             buf[BUFSIZ], *expanded;
 167         size_t           len;
 168
 169         file = get_input("Local file?");
 170         if (file == NULL || *file == '\0')
 171                 return;
 172
 173         expanded = tilde_expand(file);
 174         f = fopen(expanded, "r");
 175         if (f == NULL) {
 176                 cu_warn("%s", file);
 177                 return;
 178         }
 179
 180         while (!feof(f) && !ferror(f)) {
 181                 len = fread(buf, 1, sizeof(buf), f);
 182                 if (len != 0)
 183                         bufferevent_write(line_ev, buf, len);
 184         }
 185
 186         fclose(f);
 187         free(expanded);
 188 }
 189
 190 void
 191 send_xmodem(void)
 192 {
 193         const char      *file;
 194         char            *expanded;
 195
 196         file = get_input("Local file?");
 197         if (file == NULL || *file == '\0')
 198                 return;
 199
 200         expanded = tilde_expand(file);
 201         xmodem_send(expanded);
 202         free(expanded);
 203 }
 204
 205 void
 206 set_speed(void)
 207 {
 208         const char      *s, *errstr;
 209         int              speed;
 210
 211         s = get_input("New speed?");
 212         if (s == NULL || *s == '\0')
 213                 return;
 214
 215         speed = strtonum(s, 0, UINT_MAX, &errstr);
 216         if (errstr != NULL) {
 217                 cu_warnx("speed is %s: %s", errstr, s);
 218                 return;
 219         }
 220
 221         if (set_line(speed) != 0)
 222                 cu_warn("tcsetattr");
 223 }
 224
 225 void
 226 start_record(void)
 227 {
 228         const char      *file;
 229
 230         if (record_file != NULL) {
 231                 fclose(record_file);
 232                 record_file = NULL;
 233         }
 234
 235         file = get_input("Record file?");
 236         if (file == NULL || *file == '\0')
 237                 return;
 238
 239         record_file = fopen(file, "a");
 240         if (record_file == NULL)
 241                 cu_warnx("%s", file);
 242 }
 243
 244 void
 245 do_command(char c)
 246 {
 247         switch (c) {
 248         case '.':
 249         case '\004': /* ^D */
 250                 event_loopexit(NULL);
 251                 break;
 252         case '\032': /* ^Z */
 253                 restore_termios();
 254                 kill(getpid(), SIGTSTP);
 255                 set_termios();
 256                 break;
 257         case 'C':
 258                 connect_command();
 259                 break;
 260 #if defined(TIOCCDTR)
 261         case 'D':
 262                 ioctl(line_fd, TIOCCDTR, NULL);
 263                 sleep(1);
 264                 ioctl(line_fd, TIOCSDTR, NULL);
 265                 break;
 266 #endif
 267         case 'R':
 268                 start_record();
 269                 break;
 270         case 'S':
 271                 set_speed();
 272                 break;
 273         case 'X':
 274                 send_xmodem();
 275                 break;
 276         case '$':
 277                 pipe_command();
 278                 break;
 279         case '>':
 280                 send_file();
 281                 break;
 282         case '#':
 283                 ioctl(line_fd, TIOCSBRK, NULL);
 284                 sleep(1);
 285                 ioctl(line_fd, TIOCCBRK, NULL);
 286                 break;
 287         case '~':
 288                 bufferevent_write(line_ev, "~", 1);
 289                 break;
 290         case '?':
 291                 printf("\r\n"
 292                     "~#      send break\r\n"
 293                     "~$      pipe local command to remote host\r\n"
 294                     "~>      send file to remote host\r\n"
 295                     "~C      connect program to remote host\r\n"
 296 #if defined(TIOCCDTR)
 297                     "~D      de-assert DTR line briefly\r\n"
 298 #endif
 299                     "~R      start recording to file\r\n"
 300                     "~S      set speed\r\n"
 301                     "~X      send file with XMODEM\r\n"
 302                     "~?      get this summary\r\n"
 303                 );
 304                 break;
 305         }
 306 }