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/RFC1939-conformant POP3 servers without a LAST command, but may also
27 * be 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 = (struct idlist *)NULL;
83 ctl->oldsaved = (struct idlist *)NULL;
84 ctl->newsaved = (struct idlist *)NULL;
85 ctl->oldsavedend = &ctl->oldsaved;
91 * Croak if the uidl directory does not exist.
92 * This probably means an NFS mount failed and we can't
93 * see a uidl file that ought to be there.
94 * Question: is this a portable check? It's not clear
95 * that all implementations of lstat() will return ENOTDIR
96 * rather than plain ENOENT in this case...
98 if (lstat(idfile, &statbuf) < 0) {
101 report(stderr, GT_("lstat: %s: %s\n"), idfile, strerror(errno));
106 /* let's get stored message UIDs from previous queries */
107 if ((tmpfp = fopen(idfile, "r")) != (FILE *)NULL)
109 char buf[POPBUFSIZE+1];
110 char *host = NULL; /* pacify -Wall */
113 char *atsign; /* temp pointer used in parsing user and host */
117 char saveddelim2 = '\0'; /* pacify -Wall */
119 while (fgets(buf, POPBUFSIZE, tmpfp) != (char *)NULL)
122 * At this point, we assume the bug has two fields -- a user@host
123 * part, and an ID part. Either field may contain spurious @ signs.
124 * The previous version of this code presumed one could split at
125 * the rightmost '@'. This is not correct, as InterMail puts an
129 /* first, skip leading spaces */
130 user = buf + strspn(buf, " \t");
133 * First, we split the buf into a userhost part and an id
134 * part ... but id doesn't necessarily start with a '<',
135 * espescially if the POP server returns an X-UIDL header
136 * instead of a Message-ID, as GMX's (www.gmx.net) POP3
137 * StreamProxy V1.0 does.
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 if ((delimp1 = strchr(user, '@')) != NULL &&
146 (id = strchr(delimp1,' ')) != NULL)
148 for (delimp1 = id; delimp1 >= user; delimp1--)
149 if ((*delimp1 != ' ') && (*delimp1 != '\t'))
153 * It should be safe to assume that id starts after
154 * the " " - after all, we're writing the " "
155 * ourselves in write_saved_lists() :-)
157 id = id + strspn(id, " ");
159 delimp1++; /* but what if there is only white space ?!? */
160 saveddelim1 = *delimp1; /* save char after token */
161 *delimp1 = '\0'; /* delimit token with \0 */
164 /* now remove trailing white space chars from id */
165 if ((delimp2 = strpbrk(id, " \t\n")) != NULL ) {
166 saveddelim2 = *delimp2;
169 atsign = strrchr(user, '@');
175 for (ctl = hostlist; ctl; ctl = ctl->next) {
176 if (strcasecmp(host, ctl->server.queryname) == 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 /* return a pointer to the last element of the list to help the quick,
236 * constant-time addition to the list, NOTE: this function does not dup
237 * the string, the caller must do that. */
238 /*@shared@*/ struct idlist **save_str_quick(/*@shared@*/ struct idlist **idl,
239 /*@only@*/ char *str, flag status)
240 /* save a number/UID pair on the given UID list */
244 /* do it nonrecursively so the list is in the right order */
245 for (end = idl; *end; end = &(*end)->next)
248 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
249 (*end)->val.status.mark = status;
250 (*end)->id = (unsigned char *)str;
256 /* return the end list element for direct modification */
257 struct idlist *save_str(struct idlist **idl, const char *str, flag st)
259 return *save_str_quick(idl, str ? xstrdup(str) : NULL,
263 void free_str_list(struct idlist **idl)
264 /* free the given UID list */
266 if (*idl == (struct idlist *)NULL)
269 free_str_list(&(*idl)->next);
272 *idl = (struct idlist *)NULL;
275 void save_str_pair(struct idlist **idl, const char *str1, const char *str2)
276 /* save an ID pair on the given list */
280 /* do it nonrecursively so the list is in the right order */
281 for (end = idl; *end; end = &(*end)->next)
284 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
285 (*end)->id = str1 ? xstrdup(str1) : (char *)NULL;
287 (*end)->val.id2 = xstrdup(str2);
289 (*end)->val.id2 = (char *)NULL;
290 (*end)->next = (struct idlist *)NULL;
294 void free_str_pair_list(struct idlist **idl)
295 /* free the given ID pair list */
297 if (*idl == (struct idlist *)NULL)
300 free_idpair_list(&(*idl)->next);
302 free ((*idl)->val.id2);
304 *idl = (struct idlist *)NULL;
308 int str_in_list(struct idlist **idl, const char *str, const flag caseblind)
309 /* is a given ID in the given list? (comparison may be caseblind) */
313 for( walk = *idl; walk; walk = walk->next )
314 if( strcasecmp( str, (char *)walk->id) == 0 )
317 for( walk = *idl; walk; walk = walk->next )
318 if( strcmp( str, (char *)walk->id) == 0 )
324 int str_nr_in_list( struct idlist **idl, const char *str )
325 /* return the position of str in idl */
331 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
332 if( strcmp( str, walk->id) == 0 )
337 int str_nr_last_in_list( struct idlist **idl, const char *str)
338 /* return the last position of str in idl */
344 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
345 if( strcmp( str, walk->id) == 0 )
350 void str_set_mark( struct idlist **idl, const char *str, const flag val)
351 /* update the mark on an of an id to given value */
357 for(walk = *idl, nr = 0; walk; nr ++, walk = walk->next)
358 if (strcmp(str, walk->id) == 0)
359 walk->val.status.mark = val;
362 int count_list( struct idlist **idl)
363 /* count the number of elements in the list */
367 return 1 + count_list( &(*idl)->next );
370 /*@null@*/ char *str_from_nr_list(struct idlist **idl, long number)
371 /* return the number'th string in idl */
373 if( !*idl || number < 0)
377 return str_from_nr_list(&(*idl)->next, number-1);
381 char *str_find(struct idlist **idl, long number)
382 /* return the id of the given number in the given list. */
384 if (*idl == (struct idlist *) 0)
386 else if (number == (*idl)->val.status.num)
389 return(str_find(&(*idl)->next, number));
392 char *idpair_find(struct idlist **idl, const char *id)
393 /* return the id of the given id in the given list (caseblind comparison) */
395 if (*idl == (struct idlist *) 0)
397 else if (strcasecmp(id, (*idl)->id) == 0)
398 return((*idl)->val.id2 ? (*idl)->val.id2 : (*idl)->id);
400 return(idpair_find(&(*idl)->next, id));
403 int delete_str(struct idlist **idl, long num)
404 /* delete given message from given list */
408 for (idp = *idl; idp; idp = idp->next)
409 if (idp->val.status.num == num)
411 idp->val.status.mark = UID_DELETED;
417 struct idlist *copy_str_list(struct idlist *idl)
418 /* copy the given UID list */
420 struct idlist *newnode ;
422 if (idl == (struct idlist *)NULL)
426 newnode = (struct idlist *)xmalloc(sizeof(struct idlist));
427 memcpy(newnode, idl, sizeof(struct idlist));
428 newnode->next = copy_str_list(idl->next);
433 void append_str_list(struct idlist **idl, struct idlist **nidl)
434 /* append nidl to idl (does not copy *) */
436 if ((*nidl) == (struct idlist *)NULL || *nidl == *idl)
438 else if ((*idl) == (struct idlist *)NULL)
440 else if ((*idl)->next == (struct idlist *)NULL)
441 (*idl)->next = *nidl;
442 else if ((*idl)->next != *nidl)
443 append_str_list(&(*idl)->next, nidl);
447 void expunge_uids(struct query *ctl)
448 /* assert that all UIDs marked deleted have actually been expunged */
452 for (idl = ctl->newsaved; idl; idl = idl->next)
453 if (idl->val.status.mark == UID_DELETED)
454 idl->val.status.mark = UID_EXPUNGED;
457 void uid_swap_lists(struct query *ctl)
461 if (ctl->server.uidl && outlevel >= O_DEBUG)
465 report_build(stdout, GT_("New UID list from %s:"), ctl->server.pollname);
466 for (idp = ctl->newsaved; idp; idp = idp->next)
467 report_build(stdout, " %s = %d", idp->id, idp->val.status.mark);
469 report_build(stdout, GT_(" <empty>"));
470 report_complete(stdout, "\n");
474 * Don't swap UID lists unless we've actually seen UIDLs.
475 * This is necessary in order to keep UIDL information
476 * from being heedlessly deleted later on.
478 * Older versions of fetchmail did
480 * free_str_list(&scratchlist);
482 * after swap. This was wrong; we need to preserve the UIDL information
483 * from unqueried hosts. Unfortunately, not doing this means that
484 * under some circumstances UIDLs can end up being stored forever --
485 * specifically, if a user description is removed from .fetchmailrc
486 * with UIDLs from that account in .fetchids, there is no way for
487 * them to ever get garbage-collected.
491 /* old state of mailbox may now be irrelevant */
492 if (outlevel >= O_DEBUG)
493 report(stdout, GT_("swapping UID lists\n"));
494 free_str_list(&ctl->oldsaved);
495 ctl->oldsaved = ctl->newsaved;
496 ctl->newsaved = (struct idlist *) NULL;
498 else if (outlevel >= O_DEBUG)
499 report(stdout, GT_("not swapping UID lists, no UIDs seen this query\n"));
502 void write_saved_lists(struct query *hostlist, const char *idfile)
503 /* perform end-of-run write of seen-messages list */
510 /* if all lists are empty, nuke the file */
512 for (ctl = hostlist; ctl; ctl = ctl->next) {
513 for (idp = ctl->oldsaved; idp; idp = idp->next)
514 if (idp->val.status.mark == UID_SEEN
515 || idp->val.status.mark == UID_DELETED)
519 /* either nuke the file or write updated last-seen IDs */
520 if (!idcount && !scratchlist)
522 if (outlevel >= O_DEBUG)
523 report(stdout, GT_("Deleting fetchids file.\n"));
528 if (outlevel >= O_DEBUG)
529 report(stdout, GT_("Writing fetchids file.\n"));
530 /* FIXME: do not overwrite the old idfile */
531 if ((tmpfp = fopen(idfile, "w")) != (FILE *)NULL) {
532 for (ctl = hostlist; ctl; ctl = ctl->next) {
533 for (idp = ctl->oldsaved; idp; idp = idp->next)
534 if (idp->val.status.mark == UID_SEEN
535 || idp->val.status.mark == UID_DELETED)
536 fprintf(tmpfp, "%s@%s %s\n",
537 ctl->remotename, ctl->server.queryname, idp->id);
539 for (idp = scratchlist; idp; idp = idp->next)
540 fputs(idp->id, tmpfp);
545 #endif /* POP3_ENABLE */
547 /* uid.c ends here */