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/tws.h>
  19 #include <h/mts.h>
  20 #include <h/utils.h>
  21 #include "sbr/m_mktemp.h"
  22 #include <fcntl.h>
  23
  24 #ifdef HAVE_GETUTXENT
  25 #include <utmpx.h>
  26 #endif /* HAVE_GETUTXENT */
  27
  28 #define SCANFMT \
  29 "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\
  30 %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%>  \
  31 %{subject}%<{body}<<%{body}>>%>"
  32
  33 #define RCVTTY_SWITCHES \
  34     X("biff", 0, BIFFSW) \
  35     X("form formatfile", 0, FORMSW) \
  36     X("format string", 5, FMTSW) \
  37     X("width columns", 0, WIDTHSW) \
  38     X("newline", 0, NLSW) \
  39     X("nonewline", 0, NNLSW) \
  40     X("bell", 0, BELSW) \
  41     X("nobell", 0, NBELSW) \
  42     X("version", 0, VERSIONSW) \
  43     X("help", 0, HELPSW) \
  44
  45 #define X(sw, minchars, id) id,
  46 DEFINE_SWITCH_ENUM(RCVTTY);
  47 #undef X
  48
  49 #define X(sw, minchars, id) { sw, minchars, id },
  50 DEFINE_SWITCH_ARRAY(RCVTTY, switches);
  51 #undef X
  52
  53 static jmp_buf myctx;
  54 static int bell = 1;
  55 static int newline = 1;
  56 static int biff = 0;
  57 static int width = -1;
  58 static char *form = NULL;
  59 static char *format = NULL;
  60
  61 /*
  62  * static prototypes
  63  */
  64 static void alrmser (int);
  65 static int message_fd (char **);
  66 static int header_fd (void);
  67 #if HAVE_GETUTXENT
  68 static void alert (char *, int);
  69 #endif /* HAVE_GETUTXENT */
  70
  71
  72 int
  73 main (int argc, char **argv)
  74 {
  75     int md, vecp = 0;
  76     char *cp, *user, buf[BUFSIZ], tty[BUFSIZ];
  77     char **argp, **arguments, *vec[MAXARGS];
  78     struct utmpx *utp;
  79
  80     if (nmh_init(argv[0], 2)) { return 1; }
  81
  82     mts_init ();
  83     arguments = getarguments (invo_name, argc, argv, 1);
  84     argp = arguments;
  85
  86     while ((cp = *argp++)) {
  87         if (*cp == '-') {
  88             switch (smatch (++cp, switches)) {
  89                 case AMBIGSW:
  90                     ambigsw (cp, switches);
  91                     done (1);
  92                 case UNKWNSW:
  93                     vec[vecp++] = --cp;
  94                     continue;
  95
  96                 case HELPSW:
  97                     snprintf (buf, sizeof(buf), "%s [command ...]", invo_name);
  98                     print_help (buf, switches, 1);
  99                     done (0);
 100                 case VERSIONSW:
 101                     print_version(invo_name);
 102                     done (0);
 103
 104                 case BIFFSW:
 105                     biff = 1;
 106                     continue;
 107
 108                 case FORMSW:
 109                     if (!(form = *argp++) || *form == '-')
 110                         adios (NULL, "missing argument to %s", argp[-2]);
 111                     format = NULL;
 112                     continue;
 113                 case FMTSW:
 114                     if (!(format = *argp++) || *format == '-')
 115                         adios (NULL, "missing argument to %s", argp[-2]);
 116                     form = NULL;
 117                     continue;
 118
 119                 case WIDTHSW:
 120                     if (!(cp = *argp++) || *cp == '-')
 121                         adios(NULL, "missing argument to %s", argp[-2]);
 122                     width = atoi(cp);
 123                     continue;
 124                 case NLSW:
 125                     newline = 1;
 126                     continue;
 127                 case NNLSW:
 128                     newline = 0;
 129                     continue;
 130                 case BELSW:
 131                     bell = 1;
 132                     continue;
 133                 case NBELSW:
 134                     bell = 0;
 135                     continue;
 136
 137             }
 138         }
 139         vec[vecp++] = cp;
 140     }
 141     vec[vecp] = 0;
 142
 143     if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK)
 144         exit (RCV_MBX);
 145
 146     user = getusername();
 147
 148 #if HAVE_GETUTXENT
 149     setutxent();
 150     while ((utp = getutxent()) != NULL) {
 151         if (utp->ut_type == USER_PROCESS && utp->ut_user[0] != 0
 152                && utp->ut_line[0] != 0
 153                && strncmp (user, utp->ut_user, sizeof(utp->ut_user)) == 0) {
 154             strncpy (tty, utp->ut_line, sizeof(utp->ut_line));
 155             alert (tty, md);
 156         }
 157     }
 158     endutxent();
 159 #else
 160     NMH_UNUSED (tty);
 161     NMH_UNUSED (utp);
 162 #endif /* HAVE_GETUTXENT */
 163
 164     exit (RCV_MOK);
 165 }
 166
 167
 168 static void
 169 alrmser (int i)
 170 {
 171     NMH_UNUSED (i);
 172
 173     longjmp (myctx, 1);
 174 }
 175
 176
 177 static int
 178 message_fd (char **vec)
 179 {
 180     pid_t child_id;
 181     int bytes, seconds;
 182     int fd;
 183     char *tfile;
 184     struct stat st;
 185
 186     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 187         inform("unable to create temporary file in %s", get_temp_dir());
 188         return NOTOK;
 189     }
 190     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 191
 192     if ((child_id = fork()) == NOTOK) {
 193         /* fork error */
 194         close (fd);
 195         return header_fd ();
 196     }
 197     if (child_id) {
 198         /* parent process */
 199         if (!setjmp (myctx)) {
 200             SIGNAL (SIGALRM, alrmser);
 201             bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100;
 202
 203             /* amount of time to wait depends on message size */
 204             if (bytes <= 100) {
 205                 /* give at least 5 minutes */
 206                 seconds = 300;
 207             } else if (bytes >= 90000) {
 208                 /* but 30 minutes should be long enough */
 209                 seconds = 1800;
 210             } else {
 211                 seconds = (bytes / 60) + 300;
 212             }
 213             alarm ((unsigned int) seconds);
 214             pidwait(child_id, OK);
 215             alarm (0);
 216
 217             if (fstat (fd, &st) != NOTOK && st.st_size > 0)
 218                 return fd;
 219         } else {
 220             /*
 221              * Ruthlessly kill the child and anything
 222              * else in its process group.
 223              */
 224             killpg(child_id, SIGKILL);
 225         }
 226         close (fd);
 227         return header_fd ();
 228     }
 229
 230     /* child process */
 231     rewind (stdin);
 232     if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK)
 233         _exit (-1);
 234     closefds (3);
 235     setpgid(0, getpid());       /* put in own process group */
 236     if (execvp (vec[0], vec) == NOTOK) {
 237         _exit (-1);
 238     }
 239
 240     return NOTOK;
 241 }
 242
 243
 244 static int
 245 header_fd (void)
 246 {
 247     int fd;
 248     char *nfs;
 249     char *tfile = NULL;
 250     charstring_t scanl = NULL;
 251
 252     if ((tfile = m_mktemp2(NULL, invo_name, &fd, NULL)) == NULL) {
 253         inform("unable to create temporary file in %s", get_temp_dir());
 254         return NOTOK;
 255     }
 256     (void) m_unlink(tfile);  /* Use fd, no longer need the file name. */
 257
 258     rewind (stdin);
 259
 260     /* get new format string */
 261     nfs = new_fs (form, format, SCANFMT);
 262     scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0, &scanl);
 263     scan_finished ();
 264     if (newline) {
 265         if (write (fd, "\n\r", 2) < 0) {
 266             advise (tfile, "write LF/CR");
 267         }
 268     }
 269     if (write (fd, charstring_buffer (scanl), charstring_bytes (scanl)) < 0) {
 270         advise (tfile, "write");
 271     }
 272     charstring_free (scanl);
 273     if (bell) {
 274         if (write (fd, "\007", 1) < 0) {
 275             advise (tfile, "write BEL");
 276         }
 277     }
 278
 279     return fd;
 280 }
 281
 282
 283 #if HAVE_GETUTXENT
 284 static void
 285 alert (char *tty, int md)
 286 {
 287     int i, td, mask;
 288     char buffer[BUFSIZ], ttyspec[BUFSIZ];
 289     struct stat st;
 290
 291     snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty);
 292
 293     /*
 294      * The mask depends on whether we are checking for
 295      * write permission based on `biff' or `mesg'.
 296      */
 297     mask = biff ? S_IEXEC : (S_IWRITE >> 3);
 298     if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0)
 299         return;
 300
 301     if (setjmp (myctx)) {
 302         alarm (0);
 303         return;
 304     }
 305     SIGNAL (SIGALRM, alrmser);
 306     alarm (2);
 307     td = open (ttyspec, O_WRONLY);
 308     alarm (0);
 309     if (td == NOTOK)
 310         return;
 311
 312     lseek(md, 0, SEEK_SET);
 313
 314     while ((i = read (md, buffer, sizeof(buffer))) > 0)
 315         if (write (td, buffer, i) != i)
 316             break;
 317
 318     close (td);
 319 }
 320 #endif /* HAVE_GETUTXENT */