diplodocus.org Git - nmh/blob - uip/rcvtty.c

   1
   2 /*
   3  * rcvtty.c -- a rcvmail program (a lot like rcvalert) handling IPC ttys
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 /* Changed to use getutent() and friends.  Assumes that when getutent() exists,
  11  * a number of other things also exist.  Please check.
  12  * Ruud de Rooij <ruud@ruud.org>  Sun, 28 May 2000 17:28:55 +0200
  13  */
  14
  15 #include <h/mh.h>
  16 #include <h/signals.h>
  17 #include <setjmp.h>
  18 #include <h/rcvmail.h>
  19 #include <h/scansbr.h>
  20 #include <h/tws.h>
  21 #include <h/mts.h>
  22 #include <fcntl.h>
  23
  24 #ifdef HAVE_GETUTXENT
  25 #include <utmpx.h>
  26 #endif /* HAVE_GETUTXENT */
  27
  28 #define SCANFMT \
  29 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  30 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  31 %{subject}%<{body}<<%{body}>>%>"
  32
  33 #define RCVTTY_SWITCHES \
  34     X("biff", 0, BIFFSW) \
  35     X("form formatfile", 0, FORMSW) \
  36     X("format string", 5, FMTSW) \
  37     X("width columns", 0, WIDTHSW) \
  38     X("newline", 0, NLSW) \
  39     X("nonewline", 0, NNLSW) \
  40     X("bell", 0, BELSW) \
  41     X("nobell", 0, NBELSW) \
  42     X("version", 0, VERSIONSW) \
  43     X("help", 0, HELPSW) \
  44
  45 #define X(sw, minchars, id) id,
  46 DEFINE_SWITCH_ENUM(RCVTTY);
  47 #undef X
  48
  49 #define X(sw, minchars, id) { sw, minchars, id },
  50 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  51 #undef X
  52
  53 static jmp_buf myctx;
  54 static int bell = 1;
  55 static int newline = 1;
  56 static int biff = 0;
  57 static int width = 0;
  58 static char *form = NULL;
  59 static char *format = NULL;
  60
  61 /*
  62  * external prototypes
  63  */
  64 char *getusername(void);
  65
  66 /*
  67  * static prototypes
  68  */
  69 static void alrmser (int);
  70 static int message_fd (char **);
  71 static int header_fd (void);
  72 static void alert (char *, int);
  73
  74
  75 int
  76 main (int argc, char **argv)
  77 {
  78     int md, vecp = 0;
  79     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  80     char **argp, **arguments, *vec[MAXARGS];
  81     struct utmpx *utp;
  82 #ifdef LOCALE
  83     setlocale(LC_ALL, "");
  84 #endif
  85     invo_name = r1bindex (argv[0], '/');
  86
  87     /* read user profile/context */
  88     context_read();
  89
  90     mts_init (invo_name);
  91     arguments = getarguments (invo_name, argc, argv, 1);
  92     argp = arguments;
  93
  94     while ((cp = *argp++)) {
  95         if (*cp == '-') {
  96             switch (smatch (++cp, switches)) {
  97                 case AMBIGSW:
  98                     ambigsw (cp, switches);
  99                     done (1);
 100                 case UNKWNSW:
 101                     vec[vecp++] = --cp;
 102                     continue;
 103
 104                 case HELPSW:
 105                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
 106                     print_help (buf, switches, 1);
 107                     done (0);
 108                 case VERSIONSW:
 109                     print_version(invo_name);
 110                     done (0);
 111
 112                 case BIFFSW:
 113                     biff = 1;
 114                     continue;
 115
 116                 case FORMSW:
 117                     if (!(form = *argp++) || *form == '-')
 118                         adios (NULL, "missing argument to %s", argp[-2]);
 119                     format = NULL;
 120                     continue;
 121                 case FMTSW:
 122                     if (!(format = *argp++) || *format == '-')
 123                         adios (NULL, "missing argument to %s", argp[-2]);
 124                     form = NULL;
 125                     continue;
 126
 127                 case WIDTHSW:
 128                     if (!(cp = *argp++) || *cp == '-')
 129                         adios(NULL, "missing argument to %s", argp[-2]);
 130                     width = atoi(cp);
 131                     continue;
 132                 case NLSW:
 133                     newline = 1;
 134                     continue;
 135                 case NNLSW:
 136                     newline = 0;
 137                     continue;
 138                 case BELSW:
 139                     bell = 1;
 140                     continue;
 141                 case NBELSW:
 142                     bell = 0;
 143                     continue;
 144
 145             }
 146         }
 147         vec[vecp++] = cp;
 148     }
 149     vec[vecp] = 0;
 150
 151     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 152         exit (RCV_MBX);
 153
 154     user = getusername();
 155
 156 #if HAVE_GETUTXENT
 157     setutxent();
 158     while ((utp = getutxent()) != NULL) {
 159         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 160                && utp->ut_line[0] != 0
 161                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 162             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 163             alert (tty, md);
 164         }
 165     }
 166     endutxent();
 167 #endif /* HAVE_GETUTXENT */
 168
 169     exit (RCV_MOK);
 170     return 0;  /* dead code to satisfy the compiler */
 171 }
 172
 173
 174 static void
 175 alrmser (int i)
 176 {
 177     NMH_UNUSED (i);
 178
 179     longjmp (myctx, 1);
 180 }
 181
 182
 183 static int
 184 message_fd (char **vec)
 185 {
 186     pid_t child_id;
 187     int bytes, fd, seconds;
 188     char tmpfil[BUFSIZ];
 189     struct stat st;
 190
 191     fd = mkstemp (strncpy (tmpfil, "/tmp/rcvttyXXXXX", sizeof(tmpfil)));
 192     unlink (tmpfil);
 193
 194     if ((child_id = fork()) == NOTOK) {
 195         /* fork error */
 196         close (fd);
 197         return header_fd ();
 198     } else if (child_id) {
 199         /* parent process */
 200         if (!setjmp (myctx)) {
 201             SIGNAL (SIGALRM, alrmser);
 202             bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100;
 203
 204             /* amount of time to wait depends on message size */
 205             if (bytes <= 100) {
 206                 /* give at least 5 minutes */
 207                 seconds = 300;
 208             } else if (bytes >= 90000) {
 209                 /* but 30 minutes should be long enough */
 210                 seconds = 1800;
 211             } else {
 212                 seconds = (bytes / 60) + 300;
 213             }
 214             alarm ((unsigned int) seconds);
 215             pidwait(child_id, OK);
 216             alarm (0);
 217
 218             if (fstat (fd, &st) != NOTOK && st.st_size > (off_t) 0)
 219                 return fd;
 220         } else {
 221             /*
 222              * Ruthlessly kill the child and anything
 223              * else in its process group.
 224              */
 225             killpg(child_id, SIGKILL);
 226         }
 227         close (fd);
 228         return header_fd ();
 229     }
 230
 231     /* child process */
 232     rewind (stdin);
 233     if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK)
 234         _exit (-1);
 235     closefds (3);
 236     setpgid ((pid_t) 0, getpid ());     /* put in own process group */
 237     execvp (vec[0], vec);
 238     _exit (-1);
 239     return 1;  /* dead code to satisfy compiler */
 240 }
 241
 242
 243 static int
 244 header_fd (void)
 245 {
 246     int fd;
 247     char *nfs;
 248     char *tfile = NULL;
 249
 250     tfile = m_mktemp2(NULL, invo_name, &fd, NULL);
 251     if (tfile == NULL) return NOTOK;
 252     unlink (tfile);
 253
 254     rewind (stdin);
 255
 256     /* get new format string */
 257     nfs = new_fs (form, format, SCANFMT);
 258     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0);
 259     scan_finished ();
 260     if (newline)
 261         write (fd, "\n\r", 2);
 262     write (fd, scanl, strlen (scanl));
 263     if (bell)
 264         write (fd, "\007", 1);
 265
 266     return fd;
 267 }
 268
 269
 270 static void
 271 alert (char *tty, int md)
 272 {
 273     int i, td, mask;
 274     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 275     struct stat st;
 276
 277     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 278
 279     /*
 280      * The mask depends on whether we are checking for
 281      * write permission based on `biff' or `mesg'.
 282      */
 283     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 284     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 285         return;
 286
 287     if (!setjmp (myctx)) {
 288         SIGNAL (SIGALRM, alrmser);
 289         alarm (2);
 290         td = open (ttyspec, O_WRONLY);
 291         alarm (0);
 292         if (td == NOTOK)
 293             return;
 294     } else {
 295         alarm (0);
 296         return;
 297     }
 298
 299     lseek (md, (off_t) 0, SEEK_SET);
 300
 301     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 302         if (write (td, buffer, i) != i)
 303             break;
 304
 305     close (td);
 306 }
 307