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

   1 /* rcvtty.c -- a rcvmail program (a lot like rcvalert) handling IPC ttys
   2  *
   3  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   4  * COPYRIGHT file in the root directory of the nmh distribution for
   5  * complete copyright information.
   6  */
   7
   8 /* Changed to use getutent() and friends.  Assumes that when getutent() exists,
   9  * a number of other things also exist.  Please check.
  10  * Ruud de Rooij <ruud@ruud.org>  Sun, 28 May 2000 17:28:55 +0200
  11  */
  12
  13 #include <h/mh.h>
  14 #include <h/signals.h>
  15 #include <setjmp.h>
  16 #include <h/rcvmail.h>
  17 #include <h/scansbr.h>
  18 #include <h/fmt_scan.h>
  19 #include <h/tws.h>
  20 #include <h/mts.h>
  21 #include "h/done.h"
  22 #include <h/utils.h>
  23 #include "sbr/m_mktemp.h"
  24 #include <fcntl.h>
  25
  26 #ifdef HAVE_GETUTXENT
  27 #include <utmpx.h>
  28 #endif /* HAVE_GETUTXENT */
  29
  30 #define SCANFMT \
  31 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  32 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  33 %{subject}%<{body}<<%{body}>>%>"
  34
  35 #define RCVTTY_SWITCHES \
  36     X("biff", 0, BIFFSW) \
  37     X("form formatfile", 0, FORMSW) \
  38     X("format string", 5, FMTSW) \
  39     X("width columns", 0, WIDTHSW) \
  40     X("newline", 0, NLSW) \
  41     X("nonewline", 0, NNLSW) \
  42     X("bell", 0, BELSW) \
  43     X("nobell", 0, NBELSW) \
  44     X("version", 0, VERSIONSW) \
  45     X("help", 0, HELPSW) \
  46
  47 #define X(sw, minchars, id) id,
  48 DEFINE_SWITCH_ENUM(RCVTTY);
  49 #undef X
  50
  51 #define X(sw, minchars, id) { sw, minchars, id },
  52 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  53 #undef X
  54
  55 static jmp_buf myctx;
  56 static bool bell = true;
  57 static bool newline = true;
  58 static bool biff;
  59 static int width = -1;
  60 static char *form = NULL;
  61 static char *format = NULL;
  62
  63 /*
  64  * static prototypes
  65  */
  66 static void alrmser (int);
  67 static int message_fd (char **);
  68 static int header_fd (void);
  69 #if HAVE_GETUTXENT
  70 static void alert (char *, int);
  71 #endif /* HAVE_GETUTXENT */
  72
  73
  74 int
  75 main (int argc, char **argv)
  76 {
  77     int md, vecp = 0;
  78     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  79     char **argp, **arguments, *vec[MAXARGS];
  80     struct utmpx *utp;
  81
  82     if (nmh_init(argv[0], true, false)) { return 1; }
  83
  84     mts_init ();
  85     arguments = getarguments (invo_name, argc, argv, 1);
  86     argp = arguments;
  87
  88     while ((cp = *argp++)) {
  89         if (*cp == '-') {
  90             switch (smatch (++cp, switches)) {
  91                 case AMBIGSW:
  92                     ambigsw (cp, switches);
  93                     done (1);
  94                 case UNKWNSW:
  95                     vec[vecp++] = --cp;
  96                     continue;
  97
  98                 case HELPSW:
  99                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
 100                     print_help (buf, switches, 1);
 101                     done (0);
 102                 case VERSIONSW:
 103                     print_version(invo_name);
 104                     done (0);
 105
 106                 case BIFFSW:
 107                     biff = true;
 108                     continue;
 109
 110                 case FORMSW:
 111                     if (!(form = *argp++) || *form == '-')
 112                         die("missing argument to %s", argp[-2]);
 113                     format = NULL;
 114                     continue;
 115                 case FMTSW:
 116                     if (!(format = *argp++) || *format == '-')
 117                         die("missing argument to %s", argp[-2]);
 118                     form = NULL;
 119                     continue;
 120
 121                 case WIDTHSW:
 122                     if (!(cp = *argp++) || *cp == '-')
 123                         die("missing argument to %s", argp[-2]);
 124                     width = atoi(cp);
 125                     continue;
 126                 case NLSW:
 127                     newline = true;
 128                     continue;
 129                 case NNLSW:
 130                     newline = false;
 131                     continue;
 132                 case BELSW:
 133                     bell = true;
 134                     continue;
 135                 case NBELSW:
 136                     bell = false;
 137                     continue;
 138
 139             }
 140         }
 141         vec[vecp++] = cp;
 142     }
 143     vec[vecp] = 0;
 144
 145     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 146         exit (RCV_MBX);
 147
 148     user = getusername();
 149
 150 #if HAVE_GETUTXENT
 151     setutxent();
 152     while ((utp = getutxent()) != NULL) {
 153         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 154                && utp->ut_line[0] != 0
 155                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 156             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 157             alert (tty, md);
 158         }
 159     }
 160     endutxent();
 161 #else
 162     NMH_UNUSED (tty);
 163     NMH_UNUSED (utp);
 164 #endif /* HAVE_GETUTXENT */
 165
 166     exit (RCV_MOK);
 167 }
 168
 169
 170 static void
 171 alrmser (int i)
 172 {
 173     NMH_UNUSED (i);
 174
 175     longjmp (myctx, 1);
 176 }
 177
 178
 179 static int
 180 message_fd (char **vec)
 181 {
 182     pid_t child_id;
 183     int bytes, seconds;
 184     int fd;
 185     char *tfile;
 186     struct stat st;
 187
 188     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 189         inform("unable to create temporary file in %s", get_temp_dir());
 190         return NOTOK;
 191     }
 192     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 193
 194     if ((child_id = fork()) == NOTOK) {
 195         /* fork error */
 196         close (fd);
 197         return header_fd ();
 198     }
 199     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 > 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(0, getpid());       /* put in own process group */
 238     if (execvp (vec[0], vec) == NOTOK) {
 239         _exit(1);
 240     }
 241
 242     return NOTOK;
 243 }
 244
 245
 246 static int
 247 header_fd (void)
 248 {
 249     int fd;
 250     char *nfs;
 251     char *tfile = NULL;
 252     charstring_t scanl = NULL;
 253
 254     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 255         inform("unable to create temporary file in %s", get_temp_dir());
 256         return NOTOK;
 257     }
 258     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 259
 260     rewind (stdin);
 261
 262     /* get new format string */
 263     nfs = new_fs (form, format, SCANFMT);
 264     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0, &scanl);
 265     scan_finished ();
 266     if (newline) {
 267         if (write (fd, "\n\r", 2) < 0) {
 268             advise (tfile, "write LF/CR");
 269         }
 270     }
 271     if (write (fd, charstring_buffer (scanl), charstring_bytes (scanl)) < 0) {
 272         advise (tfile, "write");
 273     }
 274     charstring_free (scanl);
 275     if (bell) {
 276         if (write (fd, "\007", 1) < 0) {
 277             advise (tfile, "write BEL");
 278         }
 279     }
 280
 281     return fd;
 282 }
 283
 284
 285 #if HAVE_GETUTXENT
 286 static void
 287 alert (char *tty, int md)
 288 {
 289     int i, td, mask;
 290     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 291     struct stat st;
 292
 293     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 294
 295     /*
 296      * The mask depends on whether we are checking for
 297      * write permission based on `biff' or `mesg'.
 298      */
 299     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 300     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 301         return;
 302
 303     if (setjmp (myctx)) {
 304         alarm (0);
 305         return;
 306     }
 307     SIGNAL (SIGALRM, alrmser);
 308     alarm (2);
 309     td = open (ttyspec, O_WRONLY);
 310     alarm (0);
 311     if (td == NOTOK)
 312         return;
 313
 314     lseek(md, 0, SEEK_SET);
 315
 316     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 317         if (write (td, buffer, i) != i)
 318             break;
 319
 320     close (td);
 321 }
 322 #endif /* HAVE_GETUTXENT */