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 <signal.h>
  23 #include <fcntl.h>
  24
  25 #ifdef HAVE_GETUTXENT
  26 #include <utmpx.h>
  27 #endif /* HAVE_GETUTXENT */
  28
  29 #define SCANFMT \
  30 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  31 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  32 %{subject}%<{body}<<%{body}>>%>"
  33
  34 #define RCVTTY_SWITCHES \
  35     X("biff", 0, BIFFSW) \
  36     X("form formatfile", 0, FORMSW) \
  37     X("format string", 5, FMTSW) \
  38     X("width columns", 0, WIDTHSW) \
  39     X("newline", 0, NLSW) \
  40     X("nonewline", 0, NNLSW) \
  41     X("bell", 0, BELSW) \
  42     X("nobell", 0, NBELSW) \
  43     X("version", 0, VERSIONSW) \
  44     X("help", 0, HELPSW) \
  45
  46 #define X(sw, minchars, id) id,
  47 DEFINE_SWITCH_ENUM(RCVTTY);
  48 #undef X
  49
  50 #define X(sw, minchars, id) { sw, minchars, id },
  51 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  52 #undef X
  53
  54 static jmp_buf myctx;
  55 static int bell = 1;
  56 static int newline = 1;
  57 static int biff = 0;
  58 static int width = 0;
  59 static char *form = NULL;
  60 static char *format = NULL;
  61
  62 /*
  63  * external prototypes
  64  */
  65 char *getusername(void);
  66
  67 /*
  68  * static prototypes
  69  */
  70 static void alrmser (int);
  71 static int message_fd (char **);
  72 static int header_fd (void);
  73 static void alert (char *, int);
  74
  75
  76 int
  77 main (int argc, char **argv)
  78 {
  79     int md, vecp = 0;
  80     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  81     char **argp, **arguments, *vec[MAXARGS];
  82     struct utmpx *utp;
  83 #ifdef LOCALE
  84     setlocale(LC_ALL, "");
  85 #endif
  86     invo_name = r1bindex (argv[0], '/');
  87
  88     /* read user profile/context */
  89     context_read();
  90
  91     mts_init (invo_name);
  92     arguments = getarguments (invo_name, argc, argv, 1);
  93     argp = arguments;
  94
  95     while ((cp = *argp++)) {
  96         if (*cp == '-') {
  97             switch (smatch (++cp, switches)) {
  98                 case AMBIGSW:
  99                     ambigsw (cp, switches);
 100                     done (1);
 101                 case UNKWNSW:
 102                     vec[vecp++] = --cp;
 103                     continue;
 104
 105                 case HELPSW:
 106                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
 107                     print_help (buf, switches, 1);
 108                     done (0);
 109                 case VERSIONSW:
 110                     print_version(invo_name);
 111                     done (0);
 112
 113                 case BIFFSW:
 114                     biff = 1;
 115                     continue;
 116
 117                 case FORMSW:
 118                     if (!(form = *argp++) || *form == '-')
 119                         adios (NULL, "missing argument to %s", argp[-2]);
 120                     format = NULL;
 121                     continue;
 122                 case FMTSW:
 123                     if (!(format = *argp++) || *format == '-')
 124                         adios (NULL, "missing argument to %s", argp[-2]);
 125                     form = NULL;
 126                     continue;
 127
 128                 case WIDTHSW:
 129                     if (!(cp = *argp++) || *cp == '-')
 130                         adios(NULL, "missing argument to %s", argp[-2]);
 131                     width = atoi(cp);
 132                     continue;
 133                 case NLSW:
 134                     newline = 1;
 135                     continue;
 136                 case NNLSW:
 137                     newline = 0;
 138                     continue;
 139                 case BELSW:
 140                     bell = 1;
 141                     continue;
 142                 case NBELSW:
 143                     bell = 0;
 144                     continue;
 145
 146             }
 147         }
 148         vec[vecp++] = cp;
 149     }
 150     vec[vecp] = 0;
 151
 152     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 153         exit (RCV_MBX);
 154
 155     user = getusername();
 156
 157 #if HAVE_GETUTXENT
 158     setutxent();
 159     while ((utp = getutxent()) != NULL) {
 160         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 161                && utp->ut_line[0] != 0
 162                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 163             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 164             alert (tty, md);
 165         }
 166     }
 167     endutxent();
 168 #endif /* HAVE_GETUTXENT */
 169
 170     exit (RCV_MOK);
 171     return 0;  /* dead code to satisfy the compiler */
 172 }
 173
 174
 175 static void
 176 alrmser (int i)
 177 {
 178     NMH_UNUSED (i);
 179
 180     longjmp (myctx, 1);
 181 }
 182
 183
 184 static int
 185 message_fd (char **vec)
 186 {
 187     pid_t child_id;
 188     int bytes, fd, seconds;
 189     char tmpfil[BUFSIZ];
 190     struct stat st;
 191
 192     fd = mkstemp (strncpy (tmpfil, "/tmp/rcvttyXXXXX", sizeof(tmpfil)));
 193     unlink (tmpfil);
 194
 195     if ((child_id = fork()) == NOTOK) {
 196         /* fork error */
 197         close (fd);
 198         return header_fd ();
 199     } else if (child_id) {
 200         /* parent process */
 201         if (!setjmp (myctx)) {
 202             SIGNAL (SIGALRM, alrmser);
 203             bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100;
 204
 205             /* amount of time to wait depends on message size */
 206             if (bytes <= 100) {
 207                 /* give at least 5 minutes */
 208                 seconds = 300;
 209             } else if (bytes >= 90000) {
 210                 /* but 30 minutes should be long enough */
 211                 seconds = 1800;
 212             } else {
 213                 seconds = (bytes / 60) + 300;
 214             }
 215             alarm ((unsigned int) seconds);
 216             pidwait(child_id, OK);
 217             alarm (0);
 218
 219             if (fstat (fd, &st) != NOTOK && st.st_size > (off_t) 0)
 220                 return fd;
 221         } else {
 222             /*
 223              * Ruthlessly kill the child and anything
 224              * else in its process group.
 225              */
 226             killpg(child_id, SIGKILL);
 227         }
 228         close (fd);
 229         return header_fd ();
 230     }
 231
 232     /* child process */
 233     rewind (stdin);
 234     if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK)
 235         _exit (-1);
 236     closefds (3);
 237     setpgid ((pid_t) 0, getpid ());     /* put in own process group */
 238     execvp (vec[0], vec);
 239     _exit (-1);
 240     return 1;  /* dead code to satisfy compiler */
 241 }
 242
 243
 244 static int
 245 header_fd (void)
 246 {
 247     int fd;
 248     char *nfs;
 249     char *tfile = NULL;
 250
 251     tfile = m_mktemp2(NULL, invo_name, &fd, NULL);
 252     if (tfile == NULL) return NOTOK;
 253     unlink (tfile);
 254
 255     rewind (stdin);
 256
 257     /* get new format string */
 258     nfs = new_fs (form, format, SCANFMT);
 259     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0);
 260     scan_finished ();
 261     if (newline)
 262         write (fd, "\n\r", 2);
 263     write (fd, scanl, strlen (scanl));
 264     if (bell)
 265         write (fd, "\007", 1);
 266
 267     return fd;
 268 }
 269
 270
 271 static void
 272 alert (char *tty, int md)
 273 {
 274     int i, td, mask;
 275     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 276     struct stat st;
 277
 278     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 279
 280     /*
 281      * The mask depends on whether we are checking for
 282      * write permission based on `biff' or `mesg'.
 283      */
 284     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 285     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 286         return;
 287
 288     if (!setjmp (myctx)) {
 289         SIGNAL (SIGALRM, alrmser);
 290         alarm (2);
 291         td = open (ttyspec, O_WRONLY);
 292         alarm (0);
 293         if (td == NOTOK)
 294             return;
 295     } else {
 296         alarm (0);
 297         return;
 298     }
 299
 300     lseek (md, (off_t) 0, SEEK_SET);
 301
 302     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 303         if (write (td, buffer, i) != i)
 304             break;
 305
 306     close (td);
 307 }
 308