-
-
-/*
-** Check ndbm/db file(s) to see if the Message-Id of this
-** message matches the Message-Id of a previous message,
-** so we can discard it. If it doesn't match, we add the
-** Message-Id of this message to the ndbm/db file.
-*/
-static int
-suppress_duplicates(int fd, char *file)
-{
- int fd1, lockfd, state, result;
- char *cp, buf[BUFSIZ], name[NAMESZ];
- datum key, value;
- DBM *db;
- FILE *in;
-
- if ((fd1 = dup(fd)) == -1)
- return -1;
- if (!(in = fdopen(fd1, "r"))) {
- close(fd1);
- return -1;
- }
- rewind(in);
-
- for (state = FLD;;) {
- state = m_getfld(state, name, buf, sizeof(buf), in);
- switch (state) {
- case FLD:
- case FLDPLUS:
- case FLDEOF:
- /* Search for the message ID */
- if (mh_strcasecmp(name, "Message-ID")) {
- while (state == FLDPLUS)
- state = m_getfld(state, name, buf,
- sizeof(buf), in);
- continue;
- }
-
- cp = getcpy(buf);
- while (state == FLDPLUS) {
- state = m_getfld(state, name, buf,
- sizeof(buf), in);
- cp = add(buf, cp);
- }
- key.dptr = trimcpy(cp);
- key.dsize = strlen(key.dptr) + 1;
- free(cp);
- cp = key.dptr;
-
- if (!(db = dbm_open(file, O_RDWR | O_CREAT, 0600))) {
- advise(file, "unable to perform dbm_open on");
- free(cp);
- fclose(in);
- return -1;
- }
- /*
- ** Since it is difficult to portable lock a ndbm
- ** file, we will open and lock the Maildelivery
- ** file instead. This will fail if your Maildelivery
- ** file doesn't exist.
- */
- if ((lockfd = lkopen(file, O_RDWR, 0)) == -1) {
- advise(file, "unable to perform file locking on");
- free(cp);
- fclose(in);
- return -1;
- }
- value = dbm_fetch(db, key);
- if (value.dptr) {
- if (verbose)
- verbose_printf("Message-ID: %s\n already received on %s", cp, value.dptr);
- result = DONE;
- } else {
- value.dptr = ddate + sizeof("Delivery-Date:");
- value.dsize = strlen(value.dptr) + 1;
- if (dbm_store(db, key, value, DBM_INSERT))
- advise(file, "possibly corrupt file");
- result = 0;
- }
-
- dbm_close(db);
- lkclose(lockfd, file);
- free(cp);
- fclose(in);
- return result;
- break;
-
- case BODY:
- case BODYEOF:
- case FILEEOF:
- break;
-
- case LENERR:
- case FMTERR:
- default:
- break;
- }
-
- break;
- }
-
- fclose(in);
- return 0;
-}