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/ambigsw.h"
  15 #include "sbr/print_version.h"
  16 #include "sbr/print_help.h"
  17 #include "sbr/error.h"
  18 #include "h/signals.h"
  19 #include <setjmp.h>
  20 #include "h/rcvmail.h"
  21 #include "h/scansbr.h"
  22 #include "h/fmt_scan.h"
  23 #include "h/tws.h"
  24 #include "h/mts.h"
  25 #include "h/done.h"
  26 #include "h/utils.h"
  27 #include "sbr/m_mktemp.h"
  28 #include <fcntl.h>
  29
  30 #ifdef HAVE_GETUTXENT
  31 #include <utmpx.h>
  32 #endif /* HAVE_GETUTXENT */
  33
  34 #define SCANFMT \
  35 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  36 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  37 %{subject}%<{body}<<%{body}>>%>"
  38
  39 #define RCVTTY_SWITCHES \
  40     X("biff", 0, BIFFSW) \
  41     X("form formatfile", 0, FORMSW) \
  42     X("format string", 5, FMTSW) \
  43     X("width columns", 0, WIDTHSW) \
  44     X("newline", 0, NLSW) \
  45     X("nonewline", 0, NNLSW) \
  46     X("bell", 0, BELSW) \
  47     X("nobell", 0, NBELSW) \
  48     X("version", 0, VERSIONSW) \
  49     X("help", 0, HELPSW) \
  50
  51 #define X(sw, minchars, id) id,
  52 DEFINE_SWITCH_ENUM(RCVTTY);
  53 #undef X
  54
  55 #define X(sw, minchars, id) { sw, minchars, id },
  56 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  57 #undef X
  58
  59 static jmp_buf myctx;
  60 static bool bell = true;
  61 static bool newline = true;
  62 static bool biff;
  63 static int width = -1;
  64 static char *form = NULL;
  65 static char *format = NULL;
  66
  67 /*
  68  * static prototypes
  69  */
  70 static void alrmser (int);
  71 static int message_fd (char **);
  72 static int header_fd (void);
  73 #if HAVE_GETUTXENT
  74 static void alert (char *, int);
  75 #endif /* HAVE_GETUTXENT */
  76
  77
  78 int
  79 main (int argc, char **argv)
  80 {
  81     int md, vecp = 0;
  82     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  83     char **argp, **arguments, *vec[MAXARGS];
  84     struct utmpx *utp;
  85
  86     if (nmh_init(argv[0], true, false)) { return 1; }
  87
  88     mts_init ();
  89     arguments = getarguments (invo_name, argc, argv, 1);
  90     argp = arguments;
  91
  92     while ((cp = *argp++)) {
  93         if (*cp == '-') {
  94             switch (smatch (++cp, switches)) {
  95                 case AMBIGSW:
  96                     ambigsw (cp, switches);
  97                     done (1);
  98                 case UNKWNSW:
  99                     vec[vecp++] = --cp;
 100                     continue;
 101
 102                 case HELPSW:
 103                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
 104                     print_help (buf, switches, 1);
 105                     done (0);
 106                 case VERSIONSW:
 107                     print_version(invo_name);
 108                     done (0);
 109
 110                 case BIFFSW:
 111                     biff = true;
 112                     continue;
 113
 114                 case FORMSW:
 115                     if (!(form = *argp++) || *form == '-')
 116                         die("missing argument to %s", argp[-2]);
 117                     format = NULL;
 118                     continue;
 119                 case FMTSW:
 120                     if (!(format = *argp++) || *format == '-')
 121                         die("missing argument to %s", argp[-2]);
 122                     form = NULL;
 123                     continue;
 124
 125                 case WIDTHSW:
 126                     if (!(cp = *argp++) || *cp == '-')
 127                         die("missing argument to %s", argp[-2]);
 128                     width = atoi(cp);
 129                     continue;
 130                 case NLSW:
 131                     newline = true;
 132                     continue;
 133                 case NNLSW:
 134                     newline = false;
 135                     continue;
 136                 case BELSW:
 137                     bell = true;
 138                     continue;
 139                 case NBELSW:
 140                     bell = false;
 141                     continue;
 142
 143             }
 144         }
 145         vec[vecp++] = cp;
 146     }
 147     vec[vecp] = 0;
 148
 149     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 150         exit (RCV_MBX);
 151
 152     user = getusername();
 153
 154 #if HAVE_GETUTXENT
 155     setutxent();
 156     while ((utp = getutxent()) != NULL) {
 157         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 158                && utp->ut_line[0] != 0
 159                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 160             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 161             alert (tty, md);
 162         }
 163     }
 164     endutxent();
 165 #else
 166     NMH_UNUSED (tty);
 167     NMH_UNUSED (utp);
 168 #endif /* HAVE_GETUTXENT */
 169
 170     exit (RCV_MOK);
 171 }
 172
 173
 174 static void
 175 alrmser (int i)
 176 {
 177     NMH_UNUSED (i);
 178
 179     longjmp (myctx, 1);
 180 }
 181
 182
 183 static int
 184 message_fd (char **vec)
 185 {
 186     pid_t child_id;
 187     int bytes, seconds;
 188     int fd;
 189     char *tfile;
 190     struct stat st;
 191
 192     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 193         inform("unable to create temporary file in %s", get_temp_dir());
 194         return NOTOK;
 195     }
 196     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 197
 198     if ((child_id = fork()) == NOTOK) {
 199         /* fork error */
 200         close (fd);
 201         return header_fd ();
 202     }
 203     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 > 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(0, getpid());       /* put in own process group */
 242     if (execvp (vec[0], vec) == NOTOK) {
 243         _exit(1);
 244     }
 245
 246     return NOTOK;
 247 }
 248
 249
 250 static int
 251 header_fd (void)
 252 {
 253     int fd;
 254     char *nfs;
 255     char *tfile = NULL;
 256     charstring_t scanl = NULL;
 257
 258     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 259         inform("unable to create temporary file in %s", get_temp_dir());
 260         return NOTOK;
 261     }
 262     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 263
 264     rewind (stdin);
 265
 266     /* get new format string */
 267     nfs = new_fs (form, format, SCANFMT);
 268     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0, &scanl);
 269     scan_finished ();
 270     if (newline) {
 271         if (write (fd, "\n\r", 2) < 0) {
 272             advise (tfile, "write LF/CR");
 273         }
 274     }
 275     if (write (fd, charstring_buffer (scanl), charstring_bytes (scanl)) < 0) {
 276         advise (tfile, "write");
 277     }
 278     charstring_free (scanl);
 279     if (bell) {
 280         if (write (fd, "\007", 1) < 0) {
 281             advise (tfile, "write BEL");
 282         }
 283     }
 284
 285     return fd;
 286 }
 287
 288
 289 #if HAVE_GETUTXENT
 290 static void
 291 alert (char *tty, int md)
 292 {
 293     int i, td, mask;
 294     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 295     struct stat st;
 296
 297     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 298
 299     /*
 300      * The mask depends on whether we are checking for
 301      * write permission based on `biff' or `mesg'.
 302      */
 303     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 304     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 305         return;
 306
 307     if (setjmp (myctx)) {
 308         alarm (0);
 309         return;
 310     }
 311     SIGNAL (SIGALRM, alrmser);
 312     alarm (2);
 313     td = open (ttyspec, O_WRONLY);
 314     alarm (0);
 315     if (td == NOTOK)
 316         return;
 317
 318     lseek(md, 0, SEEK_SET);
 319
 320     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 321         if (write (td, buffer, i) != i)
 322             break;
 323
 324     close (td);
 325 }
 326 #endif /* HAVE_GETUTXENT */