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 "scansbr.h"
  15 #include "sbr/getarguments.h"
  16 #include "sbr/smatch.h"
  17 #include "sbr/closefds.h"
  18 #include "sbr/ambigsw.h"
  19 #include "sbr/print_version.h"
  20 #include "sbr/print_help.h"
  21 #include "sbr/error.h"
  22 #include "h/signals.h"
  23 #include <setjmp.h>
  24 #include "h/rcvmail.h"
  25 #include "h/fmt_scan.h"
  26 #include "h/tws.h"
  27 #include "h/mts.h"
  28 #include "h/done.h"
  29 #include "h/utils.h"
  30 #include "sbr/m_mktemp.h"
  31 #include <fcntl.h>
  32
  33 #ifdef HAVE_GETUTXENT
  34 #include <utmpx.h>
  35 #endif /* HAVE_GETUTXENT */
  36
  37 #define SCANFMT \
  38 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  39 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  40 %{subject}%<{body}<<%{body}>>%>"
  41
  42 #define RCVTTY_SWITCHES \
  43     X("biff", 0, BIFFSW) \
  44     X("form formatfile", 0, FORMSW) \
  45     X("format string", 5, FMTSW) \
  46     X("width columns", 0, WIDTHSW) \
  47     X("newline", 0, NLSW) \
  48     X("nonewline", 0, NNLSW) \
  49     X("bell", 0, BELSW) \
  50     X("nobell", 0, NBELSW) \
  51     X("version", 0, VERSIONSW) \
  52     X("help", 0, HELPSW) \
  53
  54 #define X(sw, minchars, id) id,
  55 DEFINE_SWITCH_ENUM(RCVTTY);
  56 #undef X
  57
  58 #define X(sw, minchars, id) { sw, minchars, id },
  59 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  60 #undef X
  61
  62 static jmp_buf myctx;
  63 static bool bell = true;
  64 static bool newline = true;
  65 static bool biff;
  66 static int width = -1;
  67 static char *form = NULL;
  68 static char *format = NULL;
  69
  70 /*
  71  * static prototypes
  72  */
  73 static void alrmser (int);
  74 static int message_fd (char **);
  75 static int header_fd (void);
  76 #if HAVE_GETUTXENT
  77 static void alert (char *, int);
  78 #endif /* HAVE_GETUTXENT */
  79
  80
  81 int
  82 main (int argc, char **argv)
  83 {
  84     int md, vecp = 0;
  85     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  86     char **argp, **arguments, *vec[MAXARGS];
  87     struct utmpx *utp;
  88
  89     if (nmh_init(argv[0], true, false)) { return 1; }
  90
  91     mts_init ();
  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 = true;
 115                     continue;
 116
 117                 case FORMSW:
 118                     if (!(form = *argp++) || *form == '-')
 119                         die("missing argument to %s", argp[-2]);
 120                     format = NULL;
 121                     continue;
 122                 case FMTSW:
 123                     if (!(format = *argp++) || *format == '-')
 124                         die("missing argument to %s", argp[-2]);
 125                     form = NULL;
 126                     continue;
 127
 128                 case WIDTHSW:
 129                     if (!(cp = *argp++) || *cp == '-')
 130                         die("missing argument to %s", argp[-2]);
 131                     width = atoi(cp);
 132                     continue;
 133                 case NLSW:
 134                     newline = true;
 135                     continue;
 136                 case NNLSW:
 137                     newline = false;
 138                     continue;
 139                 case BELSW:
 140                     bell = true;
 141                     continue;
 142                 case NBELSW:
 143                     bell = false;
 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 #else
 169     NMH_UNUSED (tty);
 170     NMH_UNUSED (utp);
 171 #endif /* HAVE_GETUTXENT */
 172
 173     exit (RCV_MOK);
 174 }
 175
 176
 177 static void
 178 alrmser (int i)
 179 {
 180     NMH_UNUSED (i);
 181
 182     longjmp (myctx, 1);
 183 }
 184
 185
 186 static int
 187 message_fd (char **vec)
 188 {
 189     pid_t child_id;
 190     int bytes, seconds;
 191     int fd;
 192     char *tfile;
 193     struct stat st;
 194
 195     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 196         inform("unable to create temporary file in %s", get_temp_dir());
 197         return NOTOK;
 198     }
 199     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 200
 201     if ((child_id = fork()) == NOTOK) {
 202         /* fork error */
 203         close (fd);
 204         return header_fd ();
 205     }
 206     if (child_id) {
 207         /* parent process */
 208         if (!setjmp (myctx)) {
 209             SIGNAL (SIGALRM, alrmser);
 210             bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100;
 211
 212             /* amount of time to wait depends on message size */
 213             if (bytes <= 100) {
 214                 /* give at least 5 minutes */
 215                 seconds = 300;
 216             } else if (bytes >= 90000) {
 217                 /* but 30 minutes should be long enough */
 218                 seconds = 1800;
 219             } else {
 220                 seconds = (bytes / 60) + 300;
 221             }
 222             alarm ((unsigned int) seconds);
 223             pidwait(child_id, OK);
 224             alarm (0);
 225
 226             if (fstat (fd, &st) != NOTOK && st.st_size > 0)
 227                 return fd;
 228         } else {
 229             /*
 230              * Ruthlessly kill the child and anything
 231              * else in its process group.
 232              */
 233             killpg(child_id, SIGKILL);
 234         }
 235         close (fd);
 236         return header_fd ();
 237     }
 238
 239     /* child process */
 240     rewind (stdin);
 241     if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK)
 242         _exit(1);
 243     closefds (3);
 244     setpgid(0, getpid());       /* put in own process group */
 245     if (execvp (vec[0], vec) == NOTOK) {
 246         _exit(1);
 247     }
 248
 249     return NOTOK;
 250 }
 251
 252
 253 static int
 254 header_fd (void)
 255 {
 256     int fd;
 257     char *nfs;
 258     char *tfile = NULL;
 259     charstring_t scanl = NULL;
 260
 261     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 262         inform("unable to create temporary file in %s", get_temp_dir());
 263         return NOTOK;
 264     }
 265     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 266
 267     rewind (stdin);
 268
 269     /* get new format string */
 270     nfs = new_fs (form, format, SCANFMT);
 271     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0, &scanl);
 272     scan_finished ();
 273     if (newline) {
 274         if (write (fd, "\n\r", 2) < 0) {
 275             advise (tfile, "write LF/CR");
 276         }
 277     }
 278     if (write (fd, charstring_buffer (scanl), charstring_bytes (scanl)) < 0) {
 279         advise (tfile, "write");
 280     }
 281     charstring_free (scanl);
 282     if (bell) {
 283         if (write (fd, "\007", 1) < 0) {
 284             advise (tfile, "write BEL");
 285         }
 286     }
 287
 288     return fd;
 289 }
 290
 291
 292 #if HAVE_GETUTXENT
 293 static void
 294 alert (char *tty, int md)
 295 {
 296     int i, td, mask;
 297     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 298     struct stat st;
 299
 300     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 301
 302     /*
 303      * The mask depends on whether we are checking for
 304      * write permission based on `biff' or `mesg'.
 305      */
 306     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 307     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 308         return;
 309
 310     if (setjmp (myctx)) {
 311         alarm (0);
 312         return;
 313     }
 314     SIGNAL (SIGALRM, alrmser);
 315     alarm (2);
 316     td = open (ttyspec, O_WRONLY);
 317     alarm (0);
 318     if (td == NOTOK)
 319         return;
 320
 321     lseek(md, 0, SEEK_SET);
 322
 323     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 324         if (write (td, buffer, i) != i)
 325             break;
 326
 327     close (td);
 328 }
 329 #endif /* HAVE_GETUTXENT */