2 * uid.c -- UIDL handling for POP3 servers without LAST
4 * For license terms, see the file COPYING in this directory.
13 #if defined(STDC_HEADERS)
17 #if defined(HAVE_UNISTD_H)
21 #include "fetchmail.h"
25 * Machinery for handling UID lists live here. This is mainly to support
26 * RFC1725-conformant POP3 servers without a LAST command, but may also be
27 * useful for making the IMAP4 querying logic UID-oriented, if a future
28 * revision of IMAP forces me to.
30 * These functions are also used by the rest of the code to maintain
35 * At start of a query, we have a (possibly empty) list of UIDs to be
36 * considered seen in `oldsaved'. These are messages that were left in
37 * the mailbox and *not deleted* on previous queries (we don't need to
38 * remember the UIDs of deleted messages because ... well, they're gone!)
39 * This list is initially set up by initialize_saved_list() from the
42 * Early in the query, during the execution of the protocol-specific
43 * getrange code, the driver expects that the host's `newsaved' member
44 * will be filled with a list of UIDs and message numbers representing
45 * the mailbox state. If this list is empty, the server did
46 * not respond to the request for a UID listing.
48 * Each time a message is fetched, we can check its UID against the
49 * `oldsaved' list to see if it is old.
51 * Each time a message-id is seen, we mark it with MARK_SEEN.
53 * Each time a message is deleted, we mark its id UID_DELETED in the
54 * `newsaved' member. When we want to assert that an expunge has been
55 * done on the server, we call expunge_uid() to register that all
56 * deleted messages are gone by marking them UID_EXPUNGED.
58 * At the end of the query, the `newsaved' member becomes the
59 * `oldsaved' list. The old `oldsaved' list is freed.
61 * At the end of the fetchmail run, seen and non-EXPUNGED members of all
62 * current `oldsaved' lists are flushed out to the .fetchids file to
63 * be picked up by the next run. If there are no un-expunged
64 * messages, the file is deleted.
66 * Note: some comparisons (those used for DNS address lists) are caseblind!
69 /* UIDs associated with un-queried hosts */
70 static struct idlist *scratchlist;
73 void initialize_saved_lists(struct query *hostlist, const char *idfile)
74 /* read file of saved IDs and attach to each host */
80 /* make sure lists are initially empty */
81 for (ctl = hostlist; ctl; ctl = ctl->next)
82 ctl->skipped = ctl->oldsaved = ctl->newsaved = (struct idlist *)NULL;
87 * Croak if the uidl directory does not exist.
88 * This probably means an NFS mount failed and we can't
89 * see a uidl file that ought to be there.
90 * Question: is this a portable check? It's not clear
91 * that all implementations of lstat() will return ENOTDIR
92 * rather than plain ENOENT in this case...
94 if (lstat(idfile, &statbuf) < 0) {
97 report(stderr, GT_("lstat: %s: %s\n"), idfile, strerror(errno));
102 /* let's get stored message UIDs from previous queries */
103 if ((tmpfp = fopen(idfile, "r")) != (FILE *)NULL)
105 char buf[POPBUFSIZE+1];
106 char *host = NULL; /* pacify -Wall */
109 char *atsign; /* temp pointer used in parsing user and host */
113 char saveddelim2 = '\0'; /* pacify -Wall */
115 while (fgets(buf, POPBUFSIZE, tmpfp) != (char *)NULL)
118 * At this point, we assume the bug has two fields -- a user@host
119 * part, and an ID part. Either field may contain spurious @ signs.
120 * The previous version of this code presumed one could split at
121 * the rightmost '@'. This is not correct, as InterMail puts an
125 /* first, skip leading spaces */
126 user = buf + strspn(buf, " \t");
129 * First, we split the buf into a userhost part and an id
130 * part ... but id doesn't necessarily start with a '<',
131 * espescially if the POP server returns an X-UIDL header
132 * instead of a Message-ID, as GMX's (www.gmx.net) POP3
133 * StreamProxy V1.0 does.
135 if ((id = strchr(user, ' ')) != NULL )
139 * this is one other trick. The userhost part
140 * may contain ' ' in the user part, at least in
141 * the lotus notes case.
142 * So we start looking for the '@' after which the
143 * host will follow with the ' ' seperator finaly id.
145 delimp1 = strchr(user, '@');
146 id = strchr(delimp1,' ');
147 for (delimp1 = id; delimp1 >= user; delimp1--)
148 if ((*delimp1 != ' ') && (*delimp1 != '\t'))
152 * It should be safe to assume that id starts after
153 * the " " - after all, we're writing the " "
154 * ourselves in write_saved_lists() :-)
156 id = id + strspn(id, " ");
158 delimp1++; /* but what if there is only white space ?!? */
159 saveddelim1 = *delimp1; /* save char after token */
160 *delimp1 = '\0'; /* delimit token with \0 */
163 /* now remove trailing white space chars from id */
164 if ((delimp2 = strpbrk(id, " \t\n")) != NULL ) {
165 saveddelim2 = *delimp2;
168 atsign = strrchr(user, '@');
174 for (ctl = hostlist; ctl; ctl = ctl->next) {
175 if (ctl->server.truename &&
176 strcasecmp(host, ctl->server.truename) == 0
177 && strcasecmp(user, ctl->remotename) == 0) {
179 save_str(&ctl->oldsaved, id, UID_SEEN);
184 * If it's not in a host we're querying,
185 * save it anyway. Otherwise we'd lose UIDL
186 * information any time we queried an explicit
189 if (ctl == (struct query *)NULL) {
191 *delimp1 = saveddelim1;
193 if (delimp2 != NULL) {
194 *delimp2 = saveddelim2;
196 save_str(&scratchlist, buf, UID_SEEN);
201 fclose(tmpfp); /* not checking should be safe, mode was "r" */
204 if (outlevel >= O_DEBUG)
209 for (ctl = hostlist; ctl; ctl = ctl->next)
210 if (ctl->server.uidl)
212 report_build(stdout, GT_("Old UID list from %s:"),
213 ctl->server.pollname);
214 for (idp = ctl->oldsaved; idp; idp = idp->next)
215 report_build(stdout, " %s", idp->id);
217 report_build(stdout, GT_(" <empty>"));
218 report_complete(stdout, "\n");
224 report_build(stdout, GT_("Scratch list of UIDs:"));
225 for (idp = scratchlist; idp; idp = idp->next)
226 report_build(stdout, " %s", idp->id);
228 report_build(stdout, GT_(" <empty>"));
229 report_complete(stdout, "\n");
233 #endif /* POP3_ENABLE */
235 struct idlist *save_str(struct idlist **idl, const char *str, flag status)
236 /* save a number/UID pair on the given UID list */
240 /* do it nonrecursively so the list is in the right order */
241 for (end = idl; *end; end = &(*end)->next)
244 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
245 (*end)->val.status.mark = status;
246 (*end)->id = str ? xstrdup(str) : (char *)NULL;
252 void free_str_list(struct idlist **idl)
253 /* free the given UID list */
255 if (*idl == (struct idlist *)NULL)
258 free_str_list(&(*idl)->next);
261 *idl = (struct idlist *)NULL;
264 void save_str_pair(struct idlist **idl, const char *str1, const char *str2)
265 /* save an ID pair on the given list */
269 /* do it nonrecursively so the list is in the right order */
270 for (end = idl; *end; end = &(*end)->next)
273 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
274 (*end)->id = str1 ? xstrdup(str1) : (char *)NULL;
276 (*end)->val.id2 = xstrdup(str2);
278 (*end)->val.id2 = (char *)NULL;
279 (*end)->next = (struct idlist *)NULL;
283 void free_str_pair_list(struct idlist **idl)
284 /* free the given ID pair list */
286 if (*idl == (struct idlist *)NULL)
289 free_idpair_list(&(*idl)->next);
291 free ((*idl)->val.id2);
293 *idl = (struct idlist *)NULL;
297 int str_in_list(struct idlist **idl, const char *str, const flag caseblind)
298 /* is a given ID in the given list? (comparison may be caseblind) */
300 if (*idl == (struct idlist *)NULL || str == (char *) NULL)
302 else if (!caseblind && strcmp(str, (*idl)->id) == 0)
304 else if (caseblind && strcasecmp(str, (*idl)->id) == 0)
307 return(str_in_list(&(*idl)->next, str, caseblind));
310 int str_nr_in_list( struct idlist **idl, const char *str )
311 /* return the position of str in idl */
317 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
318 if( strcmp( str, walk->id) == 0 )
323 int str_nr_last_in_list( struct idlist **idl, const char *str)
324 /* return the last position of str in idl */
330 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
331 if( strcmp( str, walk->id) == 0 )
336 void str_set_mark( struct idlist **idl, const char *str, const flag val)
337 /* update the mark on an of an id to given value */
343 for(walk = *idl, nr = 0; walk; nr ++, walk = walk->next)
344 if (strcmp(str, walk->id) == 0)
345 walk->val.status.mark = val;
348 int count_list( struct idlist **idl)
349 /* count the number of elements in the list */
353 return 1 + count_list( &(*idl)->next );
356 char *str_from_nr_list(struct idlist **idl, int number)
357 /* return the number'th string in idl */
359 if( !*idl || number < 0)
363 return str_from_nr_list(&(*idl)->next, number-1);
367 char *str_find(struct idlist **idl, int number)
368 /* return the id of the given number in the given list. */
370 if (*idl == (struct idlist *) 0)
372 else if (number == (*idl)->val.status.num)
375 return(str_find(&(*idl)->next, number));
378 char *idpair_find(struct idlist **idl, const char *id)
379 /* return the id of the given id in the given list (caseblind comparison) */
381 if (*idl == (struct idlist *) 0)
383 else if (strcasecmp(id, (*idl)->id) == 0)
384 return((*idl)->val.id2 ? (*idl)->val.id2 : (*idl)->id);
386 return(idpair_find(&(*idl)->next, id));
389 int delete_str(struct idlist **idl, int num)
390 /* delete given message from given list */
394 for (idp = *idl; idp; idp = idp->next)
395 if (idp->val.status.num == num)
397 idp->val.status.mark = UID_DELETED;
403 struct idlist *copy_str_list(struct idlist *idl)
404 /* copy the given UID list */
406 struct idlist *newnode ;
408 if (idl == (struct idlist *)NULL)
412 newnode = (struct idlist *)xmalloc(sizeof(struct idlist));
413 memcpy(newnode, idl, sizeof(struct idlist));
414 newnode->next = copy_str_list(idl->next);
419 void append_str_list(struct idlist **idl, struct idlist **nidl)
420 /* append nidl to idl (does not copy *) */
422 if ((*nidl) == (struct idlist *)NULL || *nidl == *idl)
424 else if ((*idl) == (struct idlist *)NULL)
426 else if ((*idl)->next == (struct idlist *)NULL)
427 (*idl)->next = *nidl;
428 else if ((*idl)->next != *nidl)
429 append_str_list(&(*idl)->next, nidl);
433 void expunge_uids(struct query *ctl)
434 /* assert that all UIDs marked deleted have actually been expunged */
438 for (idl = ctl->newsaved; idl; idl = idl->next)
439 if (idl->val.status.mark == UID_DELETED)
440 idl->val.status.mark = UID_EXPUNGED;
443 void uid_swap_lists(struct query *ctl)
447 if (ctl->server.uidl && outlevel >= O_DEBUG)
451 report_build(stdout, GT_("New UID list from %s:"), ctl->server.pollname);
452 for (idp = ctl->newsaved; idp; idp = idp->next)
453 report_build(stdout, " %s = %d", idp->id, idp->val.status.mark);
455 report_build(stdout, GT_(" <empty>"));
456 report_complete(stdout, "\n");
460 * Don't swap UID lists unless we've actually seen UIDLs.
461 * This is necessary in order to keep UIDL information
462 * from being heedlessly deleted later on.
464 * Older versions of fetchmail did
466 * free_str_list(&scratchlist);
468 * after swap. This was wrong; we need to preserve the UIDL information
469 * from unqueried hosts. Unfortunately, not doing this means that
470 * under some circumstances UIDLs can end up being stored forever --
471 * specifically, if a user description is removed from .fetchmailrc
472 * with UIDLs from that account in .fetchids, there is no way for
473 * them to ever get garbage-collected.
477 /* old state of mailbox may now be irrelevant */
478 if (outlevel >= O_DEBUG)
479 report(stdout, GT_("swapping UID lists\n"));
480 free_str_list(&ctl->oldsaved);
481 ctl->oldsaved = ctl->newsaved;
482 ctl->newsaved = (struct idlist *) NULL;
484 else if (outlevel >= O_DEBUG)
485 report(stdout, GT_("not swapping UID lists, no UIDs seen this query\n"));
488 void write_saved_lists(struct query *hostlist, const char *idfile)
489 /* perform end-of-run write of seen-messages list */
496 /* if all lists are empty, nuke the file */
498 for (ctl = hostlist; ctl; ctl = ctl->next) {
499 for (idp = ctl->oldsaved; idp; idp = idp->next)
500 if (idp->val.status.mark == UID_SEEN
501 || idp->val.status.mark == UID_DELETED)
505 /* either nuke the file or write updated last-seen IDs */
506 if (!idcount && !scratchlist)
508 if (outlevel >= O_DEBUG)
509 report(stdout, GT_("Deleting fetchids file.\n"));
514 if (outlevel >= O_DEBUG)
515 report(stdout, GT_("Writing fetchids file.\n"));
516 if ((tmpfp = fopen(idfile, "w")) != (FILE *)NULL) {
517 for (ctl = hostlist; ctl; ctl = ctl->next) {
518 for (idp = ctl->oldsaved; idp; idp = idp->next)
519 if (idp->val.status.mark == UID_SEEN
520 || idp->val.status.mark == UID_DELETED)
521 fprintf(tmpfp, "%s@%s %s\n",
522 ctl->remotename, ctl->server.truename, idp->id);
524 for (idp = scratchlist; idp; idp = idp->next)
525 fputs(idp->id, tmpfp);
530 #endif /* POP3_ENABLE */
532 /* uid.c ends here */