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