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yap-6.3/packages/clib/maildrop/rfc822/imaprefs.c
Vítor Santos Costa 40febfdf9b clib package
2010-06-17 00:40:25 +01:00

922 lines
18 KiB
C

/*
** Copyright 2000 Double Precision, Inc.
** See COPYING for distribution information.
*/
/*
** $Id$
*/
#ifndef __WINDOWS__
#include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "rfc822.h"
#include "imaprefs.h"
static void swapmsgdata(struct imap_refmsg *a, struct imap_refmsg *b)
{
char *cp;
char c;
time_t t;
unsigned long ul;
#define swap(a,b,tmp) (tmp)=(a); (a)=(b); (b)=(tmp);
swap(a->msgid, b->msgid, cp);
swap(a->isdummy, b->isdummy, c);
swap(a->flag2, b->flag2, c);
swap(a->timestamp, b->timestamp, t);
swap(a->seqnum, b->seqnum, ul);
#undef swap
}
struct imap_refmsgtable *rfc822_threadalloc()
{
struct imap_refmsgtable *p;
p=(struct imap_refmsgtable *)malloc(sizeof(struct imap_refmsgtable));
if (p)
memset(p, 0, sizeof(*p));
return (p);
}
void rfc822_threadfree(struct imap_refmsgtable *p)
{
int i;
struct imap_refmsghash *h;
struct imap_subjlookup *s;
struct imap_refmsg *m;
for (i=0; i<sizeof(p->hashtable)/sizeof(p->hashtable[0]); i++)
while ((h=p->hashtable[i]) != 0)
{
p->hashtable[i]=h->nexthash;
free(h);
}
for (i=0; i<sizeof(p->subjtable)/sizeof(p->subjtable[0]); i++)
while ((s=p->subjtable[i]) != 0)
{
p->subjtable[i]=s->nextsubj;
free(s->subj);
free(s);
}
while ((m=p->firstmsg) != 0)
{
p->firstmsg=m->next;
if (m->subj)
free(m->subj);
free(m);
}
free(p);
}
static int hashmsgid(const char *msgid)
{
unsigned long hashno=0;
while (*msgid)
{
unsigned long n= (hashno << 1);
#define HMIDS (((struct imap_refmsgtable *)0)->hashtable)
#define HHMIDSS ( sizeof(HMIDS) / sizeof( HMIDS[0] ))
if (hashno & HHMIDSS )
n ^= 1;
hashno= n ^ (unsigned char)*msgid++;
}
return (hashno % HHMIDSS);
}
struct imap_refmsg *rfc822_threadallocmsg(struct imap_refmsgtable *mt,
const char *msgid)
{
int n=hashmsgid(msgid);
struct imap_refmsg *msgp= (struct imap_refmsg *)
malloc(sizeof(struct imap_refmsg)+1+strlen(msgid));
struct imap_refmsghash *h, **hp;
if (!msgp) return (0);
memset(msgp, 0, sizeof(*msgp));
strcpy ((msgp->msgid=(char *)(msgp+1)), msgid);
h=(struct imap_refmsghash *)malloc(sizeof(struct imap_refmsghash));
if (!h)
{
free(msgp);
return (0);
}
for (hp= &mt->hashtable[n]; *hp; hp= & (*hp)->nexthash)
{
if (strcmp( (*hp)->msg->msgid, msgp->msgid) > 0)
break;
}
h->nexthash= *hp;
*hp=h;
h->msg=msgp;
msgp->last=mt->lastmsg;
if (mt->lastmsg)
mt->lastmsg->next=msgp;
else
mt->firstmsg=msgp;
mt->lastmsg=msgp;
return (msgp);
}
struct imap_refmsg *rfc822_threadsearchmsg(struct imap_refmsgtable *mt,
const char *msgid)
{
int n=hashmsgid(msgid);
struct imap_refmsghash *h;
for (h= mt->hashtable[n]; h; h= h->nexthash)
{
int rc=strcmp(h->msg->msgid, msgid);
if (rc == 0) return (h->msg);
if (rc > 0)
break;
}
return (0);
}
static int findsubj(struct imap_refmsgtable *mt, const char *s, int *isrefwd,
int create, struct imap_subjlookup **ptr)
{
char *ss=rfc822_coresubj(s, isrefwd);
int n;
struct imap_subjlookup **h;
struct imap_subjlookup *newsubj;
if (!ss) return (-1);
n=hashmsgid(ss);
for (h= &mt->subjtable[n]; *h; h= &(*h)->nextsubj)
{
int rc=strcmp((*h)->subj, ss);
if (rc == 0)
{
free(ss);
*ptr= *h;
return (0);
}
if (rc > 0)
break;
}
if (!create)
{
free(ss);
*ptr=0;
return (0);
}
newsubj=malloc(sizeof(struct imap_subjlookup));
if (!newsubj)
{
free(ss);
return (-1);
}
memset(newsubj, 0, sizeof(*newsubj));
newsubj->subj=ss;
newsubj->nextsubj= *h;
newsubj->msgisrefwd= *isrefwd;
*h=newsubj;
*ptr=newsubj;
return (0);
}
static void linkparent(struct imap_refmsg *msg, struct imap_refmsg *lastmsg)
{
msg->parent=lastmsg;
msg->prevsib=lastmsg->lastchild;
if (msg->prevsib)
msg->prevsib->nextsib=msg;
else
lastmsg->firstchild=msg;
lastmsg->lastchild=msg;
msg->nextsib=0;
}
static void breakparent(struct imap_refmsg *m)
{
if (!m->parent) return;
if (m->prevsib) m->prevsib->nextsib=m->nextsib;
else m->parent->firstchild=m->nextsib;
if (m->nextsib) m->nextsib->prevsib=m->prevsib;
else m->parent->lastchild=m->prevsib;
m->parent=0;
}
static struct imap_refmsg *dorefcreate(struct imap_refmsgtable *mt,
const char *newmsgid,
struct rfc822a *a)
/* a - references header */
{
struct imap_refmsg *lastmsg=0, *m;
struct imap_refmsg *msg;
int n;
/*
(A) Using the Message-IDs in the message's references, link
the corresponding messages together as parent/child. Make
the first reference the parent of the second (and the second
a child of the first), the second the parent of the third
(and the third a child of the second), etc. The following
rules govern the creation of these links:
If no reference message can be found with a given
Message-ID, create a dummy message with this ID. Use
this dummy message for all subsequent references to this
ID.
*/
for (n=0; n<a->naddrs; n++)
{
char *msgid=rfc822_getaddr(a, n);
msg=*msgid ? rfc822_threadsearchmsg(mt, msgid ? msgid:""):0;
if (!msg)
{
msg=rfc822_threadallocmsg(mt, msgid ? msgid:"");
if (!msg)
{
if (msgid)
free(msgid);
return (0);
}
msg->isdummy=1;
}
if (msgid)
free(msgid);
/*
If a reference message already has a parent, don't change
the existing link.
*/
if (lastmsg == 0 || msg->parent)
{
lastmsg=msg;
continue;
}
/*
Do not create a parent/child link if creating that link
would introduce a loop. For example, before making
message A the parent of B, make sure that A is not a
descendent of B.
*/
for (m=lastmsg; m; m=m->parent)
if (strcmp(m->msgid, msg->msgid) == 0)
break;
if (m)
{
lastmsg=msg;
continue;
}
linkparent(msg, lastmsg);
lastmsg=msg;
}
/*
(B) Create a parent/child link between the last reference
(or NIL if there are no references) and the current message.
If the current message has a parent already, break the
current parent/child link before creating the new one. Note
that if this message has no references, that it will now
have no parent.
NOTE: The parent/child links MUST be kept consistent with
one another at ALL times.
*/
msg=*newmsgid ? rfc822_threadsearchmsg(mt, newmsgid):0;
/*
If a message does not contain a Message-ID header line,
or the Message-ID header line does not contain a valid
Message ID, then assign a unique Message ID to this
message.
Implementation note: empty msgid, plus dupe check below,
implements that.
*/
if (msg && msg->isdummy)
{
msg->isdummy=0;
if (msg->parent)
breakparent(msg);
}
else
{
#if 1
/*
** If two or more messages have the same Message ID, assign
** a unique Message ID to each of the duplicates.
**
** Implementation note: just unlink the existing message from
** it's parents/children.
*/
if (msg)
{
while (msg->firstchild)
breakparent(msg->firstchild);
breakparent(msg);
newmsgid="";
/* Create new entry with an empty msgid, if any more
** msgids come, they'll hit the dupe check again.
*/
}
#endif
msg=rfc822_threadallocmsg(mt, newmsgid);
if (!msg) return (0);
}
if (lastmsg)
{
for (m=lastmsg; m; m=m->parent)
if (strcmp(m->msgid, msg->msgid) == 0)
break;
if (!m)
linkparent(msg, lastmsg);
}
return (msg);
}
struct imap_refmsg *rfc822_threadmsg(struct imap_refmsgtable *mt,
const char *msgidhdr,
const char *refhdr,
const char *subjheader,
const char *dateheader,
unsigned long seqnum)
{
struct rfc822t *t;
struct rfc822a *a;
struct imap_refmsg *m;
char *msgid_s;
t=rfc822t_alloc(msgidhdr ? msgidhdr:"", 0);
if (!t)
return (0);
a=rfc822a_alloc(t);
if (!a)
{
rfc822t_free(t);
return (0);
}
msgid_s=a->naddrs > 0 ? rfc822_getaddr(a, 0):strdup("");
rfc822a_free(a);
rfc822t_free(t);
if (!msgid_s)
return (0);
t=rfc822t_alloc(refhdr ? refhdr:"", 0);
if (!t)
{
free(msgid_s);
return (0);
}
a=rfc822a_alloc(t);
if (!a)
{
rfc822t_free(t);
free(msgid_s);
return (0);
}
m=dorefcreate(mt, msgid_s, a);
rfc822a_free(a);
rfc822t_free(t);
free(msgid_s);
if (!m)
return (0);
if (subjheader && (m->subj=strdup(subjheader)) == 0)
return (0); /* Cleanup in rfc822_threadfree() */
m->timestamp=dateheader ? rfc822_parsedt(dateheader):0;
m->seqnum=seqnum;
return (m);
}
/*
(2) Gather together all of the messages that have no parents
and make them all children (siblings of one another) of a dummy
parent (the "root"). These messages constitute first messages
of the threads created thus far.
*/
struct imap_refmsg *rfc822_threadgetroot(struct imap_refmsgtable *mt)
{
struct imap_refmsg *root, *m;
if (mt->rootptr)
return (mt->rootptr);
root=rfc822_threadallocmsg(mt, "(root)");
if (!root) return (0);
root->parent=root; /* Temporary */
root->isdummy=1;
for (m=mt->firstmsg; m; m=m->next)
if (!m->parent)
{
if (m->isdummy && m->firstchild == 0)
continue; /* Can happen in reference creation */
linkparent(m, root);
}
root->parent=NULL;
return (mt->rootptr=root);
}
/*
**
** (3) Prune dummy messages from the thread tree. Traverse each
** thread under the root, and for each message:
*/
void rfc822_threadprune(struct imap_refmsgtable *mt)
{
struct imap_refmsg *msg;
for (msg=mt->firstmsg; msg; msg=msg->next)
{
struct imap_refmsg *saveparent, *m;
if (!msg->parent)
continue; // The root, need it later.
if (!msg->isdummy)
continue;
/*
**
** If it is a dummy message with NO children, delete it.
*/
if (msg->firstchild == 0)
{
breakparent(msg);
/*
** Don't free the node, it'll be done on msgtable
** purge.
*/
continue;
}
/*
** If it is a dummy message with children, delete it, but
** promote its children to the current level. In other words,
** splice them in with the dummy's siblings.
**
** Do not promote the children if doing so would make them
** children of the root, unless there is only one child.
*/
if (msg->firstchild->nextsib &&
msg->parent->parent)
continue;
saveparent=msg->parent;
breakparent(msg);
while ((m=msg->firstchild) != 0)
{
breakparent(m);
linkparent(m, saveparent);
}
}
}
/*
** (4) Gather together messages under the root that have the same
** extracted subject text.
**
** (A) Create a table for associating extracted subjects with
** messages.
**
** (B) Populate the subject table with one message per
** extracted subject. For each message under the root:
*/
int rfc822_threadsortsubj(struct imap_refmsgtable *mt,
struct imap_refmsg *root)
{
struct imap_refmsg *toproot, *p;
for (toproot=root->firstchild; toproot; toproot=toproot->nextsib)
{
const char *subj;
struct imap_subjlookup *subjtop;
int isrefwd;
/*
** (i) Find the subject of this thread by extracting the
** base subject from the current message, or its first child
** if the current message is a dummy.
*/
p=toproot;
if (p->isdummy)
p=p->firstchild;
subj=p->subj ? p->subj:"";
/*
** (ii) If the extracted subject is empty, skip this
** message.
*/
if (*subj == 0)
continue;
/*
** (iii) Lookup the message associated with this extracted
** subject in the table.
*/
if (findsubj(mt, subj, &isrefwd, 1, &subjtop))
return (-1);
/*
**
** (iv) If there is no message in the table with this
** subject, add the current message and the extracted
** subject to the subject table.
*/
if (subjtop->msg == 0)
{
subjtop->msg=toproot;
subjtop->msgisrefwd=isrefwd;
continue;
}
/*
** Otherwise, replace the message in the table with the
** current message if the message in the table is not a
** dummy AND either of the following criteria are true:
*/
if (!subjtop->msg->isdummy)
{
/*
** The current message is a dummy
**
*/
if (toproot->isdummy)
{
subjtop->msg=toproot;
subjtop->msgisrefwd=isrefwd;
continue;
}
/*
** The message in the table is a reply or forward (its
** original subject contains a subj-refwd part and/or a
** "(fwd)" subj-trailer) and the current message is
not.
*/
if (subjtop->msgisrefwd && !isrefwd)
{
subjtop->msg=toproot;
subjtop->msgisrefwd=isrefwd;
}
}
}
return (0);
}
/*
** (C) Merge threads with the same subject. For each message
** under the root:
*/
int rfc822_threadmergesubj(struct imap_refmsgtable *mt,
struct imap_refmsg *root)
{
struct imap_refmsg *toproot, *p, *q, *nextroot;
char *str;
for (toproot=root->firstchild; toproot; toproot=nextroot)
{
const char *subj;
struct imap_subjlookup *subjtop;
int isrefwd;
nextroot=toproot->nextsib;
/*
** (i) Find the subject of this thread as in step 4.B.i
** above.
*/
p=toproot;
if (p->isdummy)
p=p->firstchild;
subj=p->subj ? p->subj:"";
/*
** (ii) If the extracted subject is empty, skip this
** message.
*/
if (*subj == 0)
continue;
/*
** (iii) Lookup the message associated with this extracted
** subject in the table.
*/
if (findsubj(mt, subj, &isrefwd, 0, &subjtop) || subjtop == 0)
return (-1);
/*
** (iv) If the message in the table is the current message,
** skip it.
*/
/* NOTE - ptr comparison IS NOT LEGAL */
subjtop->msg->flag2=1;
if (toproot->flag2)
{
toproot->flag2=0;
continue;
}
subjtop->msg->flag2=0;
/*
** Otherwise, merge the current message with the one in the
** table using the following rules:
**
** If both messages are dummies, append the current
** message's children to the children of the message in
** the table (the children of both messages become
** siblings), and then delete the current message.
*/
if (subjtop->msg->isdummy && toproot->isdummy)
{
while ((p=toproot->firstchild) != 0)
{
breakparent(p);
linkparent(p, subjtop->msg);
}
breakparent(toproot);
continue;
}
/*
** If the message in the table is a dummy and the current
** message is not, make the current message a child of
** the message in the table (a sibling of it's children).
*/
if (subjtop->msg->isdummy)
{
breakparent(toproot);
linkparent(toproot, subjtop->msg);
continue;
}
/*
** If the current message is a reply or forward and the
** message in the table is not, make the current message
** a child of the message in the table (a sibling of it's
** children).
*/
if (isrefwd)
{
p=subjtop->msg;
if (p->isdummy)
p=p->firstchild;
subj=p->subj ? p->subj:"";
str=rfc822_coresubj(subj, &isrefwd);
if (!str)
return (-1);
free(str); /* Don't really care */
if (!isrefwd)
{
breakparent(toproot);
linkparent(toproot, subjtop->msg);
continue;
}
}
/*
** Otherwise, create a new dummy container and make both
** messages children of the dummy, and replace the
** message in the table with the dummy message.
*/
/* What we do is create a new message, then move the
** contents of subjtop->msg (including its children)
** to the new message, then make the new message a child
** of subjtop->msg, and mark subjtop->msg as a dummy msg.
*/
q=rfc822_threadallocmsg(mt, "(dummy)");
if (!q)
return (-1);
q->isdummy=1;
swapmsgdata(q, subjtop->msg);
while ((p=subjtop->msg->firstchild) != 0)
{
breakparent(p);
linkparent(p, q);
}
linkparent(q, subjtop->msg);
breakparent(toproot);
linkparent(toproot, subjtop->msg);
}
return (0);
}
/*
** (5) Traverse the messages under the root and sort each set of
** siblings by date. Traverse the messages in such a way that the
** "youngest" set of siblings are sorted first, and the "oldest"
** set of siblings are sorted last (grandchildren are sorted
** before children, etc). In the case of an exact match on date,
** use the order in which the messages appear in the mailbox (that
** is, by sequence number) to determine the order. In the case of
** a dummy message (which can only occur with top-level siblings),
** use its first child for sorting.
*/
static int cmp_msgs(const void *a, const void *b)
{
struct imap_refmsg *ma=*(struct imap_refmsg **)a;
struct imap_refmsg *mb=*(struct imap_refmsg **)b;
time_t ta, tb;
unsigned long na, nb;
while (ma && ma->isdummy)
ma=ma->firstchild;
while (mb && mb->isdummy)
mb=mb->firstchild;
ta=tb=0;
na=nb=0;
if (ma)
{
ta=ma->timestamp;
na=ma->seqnum;
}
if (mb)
{
tb=mb->timestamp;
nb=mb->seqnum;
}
return (ta < tb ? -1: ta > tb ? 1:
na < nb ? -1: na > nb ? 1:0);
}
struct imap_threadsortinfo {
struct imap_refmsgtable *mt;
struct imap_refmsg **sort_table;
size_t sort_table_cnt;
} ;
static int dothreadsort(struct imap_threadsortinfo *,
struct imap_refmsg *);
int rfc822_threadsortbydate(struct imap_refmsgtable *mt)
{
struct imap_threadsortinfo itsi;
int rc;
itsi.mt=mt;
itsi.sort_table=0;
itsi.sort_table_cnt=0;
rc=dothreadsort(&itsi, mt->rootptr);
if (itsi.sort_table)
free(itsi.sort_table);
return (rc);
}
static int dothreadsort(struct imap_threadsortinfo *itsi,
struct imap_refmsg *p)
{
struct imap_refmsg *q;
size_t i, n;
for (q=p->firstchild; q; q=q->nextsib)
dothreadsort(itsi, q);
n=0;
for (q=p->firstchild; q; q=q->nextsib)
++n;
if (n > itsi->sort_table_cnt)
{
struct imap_refmsg **new_array=(struct imap_refmsg **)
(itsi->sort_table ?
realloc(itsi->sort_table,
sizeof(struct imap_refmsg *)*n)
:malloc(sizeof(struct imap_refmsg *)*n));
if (!new_array)
return (-1);
itsi->sort_table=new_array;
itsi->sort_table_cnt=n;
}
n=0;
while ((q=p->firstchild) != 0)
{
breakparent(q);
itsi->sort_table[n++]=q;
}
qsort(itsi->sort_table, n, sizeof(struct imap_refmsg *), cmp_msgs);
for (i=0; i<n; i++)
linkparent(itsi->sort_table[i], p);
return (0);
}
struct imap_refmsg *rfc822_thread(struct imap_refmsgtable *mt)
{
if (!mt->rootptr)
{
rfc822_threadprune(mt);
if ((mt->rootptr=rfc822_threadgetroot(mt)) == 0)
return (0);
if (rfc822_threadsortsubj(mt, mt->rootptr) ||
rfc822_threadmergesubj(mt, mt->rootptr) ||
rfc822_threadsortbydate(mt))
{
mt->rootptr=0;
return (0);
}
}
return (mt->rootptr);
}