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 static struct swit switches[] = {
  35 #define BIFFSW  0
  36     { "biff", 0 },
  37 #define FORMSW  1
  38     { "form formatfile", 0 },
  39 #define FMTSW   2
  40     { "format string", 5 },
  41 #define WIDTHSW 3
  42     { "width columns", 0 },
  43 #define NLSW    4
  44     { "newline", 0 },
  45 #define NNLSW   5
  46     { "nonewline", 0 },
  47 #define BELSW   6
  48     { "bell", 0 },
  49 #define NBELSW  7
  50     { "nobell", 0 },
  51 #define VERSIONSW 8
  52     { "version", 0 },
  53 #define HELPSW  9
  54     { "help", 0 },
  55     { NULL, 0 }
  56 };
  57
  58 static jmp_buf myctx;
  59 static int bell = 1;
  60 static int newline = 1;
  61 static int biff = 0;
  62 static int width = 0;
  63 static char *form = NULL;
  64 static char *format = NULL;
  65
  66 /*
  67  * external prototypes
  68  */
  69 char *getusername(void);
  70
  71 /*
  72  * static prototypes
  73  */
  74 static void alrmser (int);
  75 static int message_fd (char **);
  76 static int header_fd (void);
  77 static void alert (char *, int);
  78
  79
  80 int
  81 main (int argc, char **argv)
  82 {
  83     int md, vecp = 0;
  84     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  85     char **argp, **arguments, *vec[MAXARGS];
  86     struct utmpx *utp;
  87 #ifdef LOCALE
  88     setlocale(LC_ALL, "");
  89 #endif
  90     invo_name = r1bindex (argv[0], '/');
  91
  92     /* read user profile/context */
  93     context_read();
  94
  95     mts_init (invo_name);
  96     arguments = getarguments (invo_name, argc, argv, 1);
  97     argp = arguments;
  98
  99     while ((cp = *argp++)) {
 100         if (*cp == '-') {
 101             switch (smatch (++cp, switches)) {
 102                 case AMBIGSW:
 103                     ambigsw (cp, switches);
 104                     done (1);
 105                 case UNKWNSW:
 106                     vec[vecp++] = --cp;
 107                     continue;
 108
 109                 case HELPSW:
 110                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
 111                     print_help (buf, switches, 1);
 112                     done (1);
 113                 case VERSIONSW:
 114                     print_version(invo_name);
 115                     done (1);
 116
 117                 case BIFFSW:
 118                     biff = 1;
 119                     continue;
 120
 121                 case FORMSW:
 122                     if (!(form = *argp++) || *form == '-')
 123                         adios (NULL, "missing argument to %s", argp[-2]);
 124                     format = NULL;
 125                     continue;
 126                 case FMTSW:
 127                     if (!(format = *argp++) || *format == '-')
 128                         adios (NULL, "missing argument to %s", argp[-2]);
 129                     form = NULL;
 130                     continue;
 131
 132                 case WIDTHSW:
 133                     if (!(cp = *argp++) || *cp == '-')
 134                         adios(NULL, "missing argument to %s", argp[-2]);
 135                     width = atoi(cp);
 136                     continue;
 137                 case NLSW:
 138                     newline = 1;
 139                     continue;
 140                 case NNLSW:
 141                     newline = 0;
 142                     continue;
 143                 case BELSW:
 144                     bell = 1;
 145                     continue;
 146                 case NBELSW:
 147                     bell = 0;
 148                     continue;
 149
 150             }
 151         }
 152         vec[vecp++] = cp;
 153     }
 154     vec[vecp] = 0;
 155
 156     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 157         exit (RCV_MBX);
 158
 159     user = getusername();
 160
 161 #if HAVE_GETUTXENT
 162     setutxent();
 163     while ((utp = getutxent()) != NULL) {
 164         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 165                && utp->ut_line[0] != 0
 166                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 167             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 168             alert (tty, md);
 169         }
 170     }
 171     endutxent();
 172 #endif /* HAVE_GETUTXENT */
 173
 174     exit (RCV_MOK);
 175     return 0;  /* dead code to satisfy the compiler */
 176 }
 177
 178
 179 static void
 180 alrmser (int i)
 181 {
 182     NMH_UNUSED (i);
 183
 184     longjmp (myctx, 1);
 185 }
 186
 187
 188 static int
 189 message_fd (char **vec)
 190 {
 191     pid_t child_id;
 192     int bytes, fd, seconds;
 193     char tmpfil[BUFSIZ];
 194     struct stat st;
 195
 196     fd = mkstemp (strncpy (tmpfil, "/tmp/rcvttyXXXXX", sizeof(tmpfil)));
 197     unlink (tmpfil);
 198
 199     if ((child_id = vfork()) == NOTOK) {
 200         /* fork error */
 201         close (fd);
 202         return header_fd ();
 203     } else if (child_id) {
 204         /* parent process */
 205         if (!setjmp (myctx)) {
 206             SIGNAL (SIGALRM, alrmser);
 207             bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100;
 208
 209             /* amount of time to wait depends on message size */
 210             if (bytes <= 100) {
 211                 /* give at least 5 minutes */
 212                 seconds = 300;
 213             } else if (bytes >= 90000) {
 214                 /* but 30 minutes should be long enough */
 215                 seconds = 1800;
 216             } else {
 217                 seconds = (bytes / 60) + 300;
 218             }
 219             alarm ((unsigned int) seconds);
 220             pidwait(child_id, OK);
 221             alarm (0);
 222
 223             if (fstat (fd, &st) != NOTOK && st.st_size > (off_t) 0)
 224                 return fd;
 225         } else {
 226             /*
 227              * Ruthlessly kill the child and anything
 228              * else in its process group.
 229              */
 230             killpg(child_id, SIGKILL);
 231         }
 232         close (fd);
 233         return header_fd ();
 234     }
 235
 236     /* child process */
 237     rewind (stdin);
 238     if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK)
 239         _exit (-1);
 240     closefds (3);
 241     setpgid ((pid_t) 0, getpid ());     /* put in own process group */
 242     execvp (vec[0], vec);
 243     _exit (-1);
 244     return 1;  /* dead code to satisfy compiler */
 245 }
 246
 247
 248 static int
 249 header_fd (void)
 250 {
 251     int fd;
 252     char *nfs;
 253     char *tfile = NULL;
 254
 255     tfile = m_mktemp2(NULL, invo_name, &fd, NULL);
 256     if (tfile == NULL) return NOTOK;
 257     unlink (tfile);
 258
 259     rewind (stdin);
 260
 261     /* get new format string */
 262     nfs = new_fs (form, format, SCANFMT);
 263     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0);
 264     if (newline)
 265         write (fd, "\n\r", 2);
 266     write (fd, scanl, strlen (scanl));
 267     if (bell)
 268         write (fd, "\007", 1);
 269
 270     return fd;
 271 }
 272
 273
 274 static void
 275 alert (char *tty, int md)
 276 {
 277     int i, td, mask;
 278     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 279     struct stat st;
 280
 281     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 282
 283     /*
 284      * The mask depends on whether we are checking for
 285      * write permission based on `biff' or `mesg'.
 286      */
 287     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 288     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 289         return;
 290
 291     if (!setjmp (myctx)) {
 292         SIGNAL (SIGALRM, alrmser);
 293         alarm (2);
 294         td = open (ttyspec, O_WRONLY);
 295         alarm (0);
 296         if (td == NOTOK)
 297             return;
 298     } else {
 299         alarm (0);
 300         return;
 301     }
 302
 303     lseek (md, (off_t) 0, SEEK_SET);
 304
 305     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 306         if (write (td, buffer, i) != i)
 307             break;
 308
 309     close (td);
 310 }
 311