2 * uid.c -- UIDL handling for POP3 servers without LAST
4 * For license terms, see the file COPYING in this directory.
11 #if defined(STDC_HEADERS)
15 #if defined(HAVE_UNISTD_H)
19 #include "fetchmail.h"
22 * Machinery for handling UID lists live here. This is mainly to support
23 * RFC1725-conformant POP3 servers without a LAST command, but may also be
24 * useful for making the IMAP4 querying logic UID-oriented, if a future
25 * revision of IMAP forces me to.
27 * These functions are also used by the rest of the code to maintain
32 * At start of a query, we have a (possibly empty) list of UIDs to be
33 * considered seen in `oldsaved'. These are messages that were left in
34 * the mailbox and *not deleted* on previous queries (we don't need to
35 * remember the UIDs of deleted messages because ... well, they're gone!)
36 * This list is initially set up by initialize_saved_list() from the
39 * Early in the query, during the execution of the protocol-specific
40 * getrange code, the driver expects that the host's `newsaved' member
41 * will be filled with a list of UIDs and message numbers representing
42 * the mailbox state. If this list is empty, the server did
43 * not respond to the request for a UID listing.
45 * Each time a message is fetched, we can check its UID against the
46 * `oldsaved' list to see if it is old.
48 * Each time a message-id is seen, we mark it with MARK_SEEN.
50 * Each time a message is deleted, we mark its id UID_DELETED in the
51 * `newsaved' member. When we want to assert that an expunge has been
52 * done on the server, we call expunge_uid() to register that all
53 * deleted messages are gone by marking them UID_EXPUNGED.
55 * At the end of the query, the `newsaved' member becomes the
56 * `oldsaved' list. The old `oldsaved' list is freed.
58 * At the end of the fetchmail run, seen and non-EXPUNGED members of all
59 * current `oldsaved' lists are flushed out to the .fetchids file to
60 * be picked up by the next run. If there are no un-expunged
61 * messages, the file is deleted.
63 * Note: some comparisons (those used for DNS address lists) are caseblind!
66 /* UIDs associated with un-queried hosts */
67 static struct idlist *scratchlist;
70 void initialize_saved_lists(struct query *hostlist, const char *idfile)
71 /* read file of saved IDs and attach to each host */
77 /* make sure lists are initially empty */
78 for (ctl = hostlist; ctl; ctl = ctl->next)
79 ctl->skipped = ctl->oldsaved = ctl->newsaved = (struct idlist *)NULL;
81 /* let's get stored message UIDs from previous queries */
82 if ((tmpfp = fopen(idfile, "r")) != (FILE *)NULL) {
83 char buf[POPBUFSIZE+1],host[HOSTLEN+1],user[USERNAMELEN+1],id[IDLEN+1];
85 while (fgets(buf, POPBUFSIZE, tmpfp) != (char *)NULL)
88 * This inelegant hack was brought to you by the fact that
89 * some dial-up resellers actually use account names with
90 * @ in them. So we need to split on the rightmost @...
92 char *atsign = strrchr(buf, '@');
97 if ((st = sscanf(buf, "%s %s %s\n", user, host, id)) == 3)
99 for (ctl = hostlist; ctl; ctl = ctl->next)
101 if (ctl->server.truename &&
102 strcasecmp(host, ctl->server.truename) == 0
103 && strcasecmp(user, ctl->remotename) == 0)
105 save_str(&ctl->oldsaved, id, UID_SEEN);
110 /* if it's not in a host we're querying, save it anyway */
111 if (ctl == (struct query *)NULL)
112 save_str(&scratchlist, buf, UID_SEEN);
118 if (outlevel >= O_DEBUG)
123 for (ctl = hostlist; ctl; ctl = ctl->next)
124 if (ctl->server.uidl)
126 report_build(stdout, "Old UID list from %s:",ctl->server.pollname);
127 for (idp = ctl->oldsaved; idp; idp = idp->next)
128 report_build(stdout, " %s", idp->id);
130 report_build(stdout, " <empty>");
131 report_complete(stdout, "\n");
137 report_build(stdout, "Scratch list of UIDs:");
138 for (idp = scratchlist; idp; idp = idp->next)
139 report_build(stdout, " %s", idp->id);
141 report_build(stdout, " <empty>");
142 report_complete(stdout, "\n");
146 #endif /* POP3_ENABLE */
148 struct idlist *save_str(struct idlist **idl, const char *str, flag status)
149 /* save a number/UID pair on the given UID list */
153 /* do it nonrecursively so the list is in the right order */
154 for (end = idl; *end; end = &(*end)->next)
157 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
158 (*end)->val.status.mark = status;
159 (*end)->id = str ? xstrdup(str) : (char *)NULL;
165 void free_str_list(struct idlist **idl)
166 /* free the given UID list */
168 if (*idl == (struct idlist *)NULL)
171 free_str_list(&(*idl)->next);
174 *idl = (struct idlist *)NULL;
177 void save_str_pair(struct idlist **idl, const char *str1, const char *str2)
178 /* save an ID pair on the given list */
182 /* do it nonrecursively so the list is in the right order */
183 for (end = idl; *end; end = &(*end)->next)
186 *end = (struct idlist *)xmalloc(sizeof(struct idlist));
187 (*end)->id = str1 ? xstrdup(str1) : (char *)NULL;
189 (*end)->val.id2 = xstrdup(str2);
191 (*end)->val.id2 = (char *)NULL;
192 (*end)->next = (struct idlist *)NULL;
196 void free_str_pair_list(struct idlist **idl)
197 /* free the given ID pair list */
199 if (*idl == (struct idlist *)NULL)
202 free_idpair_list(&(*idl)->next);
204 free ((*idl)->val.id2);
206 *idl = (struct idlist *)NULL;
210 int str_in_list(struct idlist **idl, const char *str, const flag caseblind)
211 /* is a given ID in the given list? (comparison may be caseblind) */
213 if (*idl == (struct idlist *)NULL || str == (char *) NULL)
215 else if (!caseblind && strcmp(str, (*idl)->id) == 0)
217 else if (caseblind && strcasecmp(str, (*idl)->id) == 0)
220 return(str_in_list(&(*idl)->next, str, caseblind));
223 int str_nr_in_list( struct idlist **idl, const char *str )
224 /* return the position of str in idl */
230 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
231 if( strcmp( str, walk->id) == 0 )
236 int str_nr_last_in_list( struct idlist **idl, const char *str)
237 /* return the last position of str in idl */
243 for( walk = *idl, nr = 0; walk; nr ++, walk = walk->next )
244 if( strcmp( str, walk->id) == 0 )
249 void str_set_mark( struct idlist **idl, const char *str, const flag val)
250 /* update the mark on an of an id to given value */
256 for(walk = *idl, nr = 0; walk; nr ++, walk = walk->next)
257 if (strcmp(str, walk->id) == 0)
258 walk->val.status.mark = val;
261 int count_list( struct idlist **idl)
262 /* count the number of elements in the list */
266 return 1 + count_list( &(*idl)->next );
269 char *str_from_nr_list(struct idlist **idl, int number)
270 /* return the number'th string in idl */
272 if( !*idl || number < 0)
276 return str_from_nr_list(&(*idl)->next, number-1);
280 char *str_find(struct idlist **idl, int number)
281 /* return the id of the given number in the given list. */
283 if (*idl == (struct idlist *) 0)
285 else if (number == (*idl)->val.status.num)
288 return(str_find(&(*idl)->next, number));
291 char *idpair_find(struct idlist **idl, const char *id)
292 /* return the id of the given id in the given list (caseblind comparison) */
294 if (*idl == (struct idlist *) 0)
296 else if (strcasecmp(id, (*idl)->id) == 0)
297 return((*idl)->val.id2 ? (*idl)->val.id2 : (*idl)->id);
299 return(idpair_find(&(*idl)->next, id));
302 int delete_str(struct idlist **idl, int num)
303 /* delete given message from given list */
307 for (idp = *idl; idp; idp = idp->next)
308 if (idp->val.status.num == num)
310 idp->val.status.mark = UID_DELETED;
316 void append_str_list(struct idlist **idl, struct idlist **nidl)
317 /* append nidl to idl (does not copy *) */
319 if ((*nidl) == (struct idlist *)NULL || *nidl == *idl)
321 else if ((*idl) == (struct idlist *)NULL)
323 else if ((*idl)->next == (struct idlist *)NULL)
324 (*idl)->next = *nidl;
325 else if ((*idl)->next != *nidl)
326 append_str_list(&(*idl)->next, nidl);
330 void expunge_uids(struct query *ctl)
331 /* assert that all UIDs marked deleted have actually been expunged */
335 for (idl = ctl->newsaved; idl; idl = idl->next)
336 if (idl->val.status.mark == UID_DELETED)
337 idl->val.status.mark = UID_EXPUNGED;
340 void update_str_lists(struct query *ctl)
341 /* perform end-of-query actions on UID lists */
343 free_str_list(&ctl->oldsaved);
344 free_str_list(&scratchlist);
345 ctl->oldsaved = ctl->newsaved;
346 ctl->newsaved = (struct idlist *) NULL;
348 if (ctl->server.uidl && outlevel >= O_DEBUG)
352 report_build(stdout, "New UID list from %s:", ctl->server.pollname);
353 for (idp = ctl->oldsaved; idp; idp = idp->next)
354 report_build(stdout, " %s = %d", idp->id, idp->val.status.mark);
356 report_build(stdout, " <empty>");
357 report_complete(stdout, "\n");
361 void write_saved_lists(struct query *hostlist, const char *idfile)
362 /* perform end-of-run write of seen-messages list */
369 /* if all lists are empty, nuke the file */
371 for (ctl = hostlist; ctl; ctl = ctl->next) {
376 /* either nuke the file or write updated last-seen IDs */
377 if (!idcount && !scratchlist)
379 if (outlevel >= O_DEBUG)
380 report(stdout, "Deleting fetchids file.\n");
384 if ((tmpfp = fopen(idfile, "w")) != (FILE *)NULL) {
385 for (ctl = hostlist; ctl; ctl = ctl->next) {
386 for (idp = ctl->oldsaved; idp; idp = idp->next)
387 if (idp->val.status.mark == UID_SEEN
388 || idp->val.status.mark == UID_DELETED)
389 fprintf(tmpfp, "%s@%s %s\n",
390 ctl->remotename, ctl->server.truename, idp->id);
392 for (idp = scratchlist; idp; idp = idp->next)
393 fputs(idp->id, tmpfp);
397 #endif /* POP3_ENABLE */
399 /* uid.c ends here */