From 858b33924fa10528df6d1938b981841bcca86122 Mon Sep 17 00:00:00 2001
From: Art Cancro <ajc@citadel.org>
Date: Wed, 16 Feb 2000 01:19:39 +0000
Subject: [PATCH] * Vanquished the evil dn_expand() beast.  getmx() now seems
 to be working.

---
 citadel/ChangeLog   |   4 ++
 citadel/Makefile.in |   2 +-
 citadel/domain.c    | 105 ++++++++++++++++++++++++++++++++++----------
 citadel/domain.h    |   6 +++
 4 files changed, 94 insertions(+), 23 deletions(-)

diff --git a/citadel/ChangeLog b/citadel/ChangeLog
index 8fb8b16d7..424ec73aa 100644
--- a/citadel/ChangeLog
+++ b/citadel/ChangeLog
@@ -1,4 +1,7 @@
 $Log$
+Revision 1.459  2000/02/16 01:19:39  ajc
+* Vanquished the evil dn_expand() beast.  getmx() now seems to be working.
+
 Revision 1.458  2000/02/14 04:36:14  ajc
 * sysdep.c: added new event hook type EVT_TIMER.  Timer event hooks are called
   once per minute by any worker thread.
@@ -1623,3 +1626,4 @@ Sat Jul 11 00:20:48 EDT 1998 Nathan Bryant <bryant@cs.usm.maine.edu>
 
 Fri Jul 10 1998 Art Cancro <ajc@uncnsrd.mt-kisco.ny.us>
 	* Initial CVS import 
+
diff --git a/citadel/Makefile.in b/citadel/Makefile.in
index b29dcd5d7..3cf0d2cf3 100644
--- a/citadel/Makefile.in
+++ b/citadel/Makefile.in
@@ -64,7 +64,7 @@ AUTOCONF=@AUTOCONF@
 VPATH=$(srcdir)
 
 SOURCES=aidepost.c citadel.c citmail.c citserver.c client_chat.c commands.c \
-	config.c control.c cux2ascii.c database.c dynloader.c file_ops.c \
+	config.c control.c database.c dynloader.c file_ops.c \
 	housekeeping.c internetmail.c ipc_c_tcp.c locate_host.c \
 	logging.c mailinglist.c messages.c msgbase.c msgform.c netmailer.c \
 	netpoll.c netproc.c netsetup.c policy.c proxy.c rcit.c readlog.c \
diff --git a/citadel/domain.c b/citadel/domain.c
index c02aa303c..4c35a3bdb 100644
--- a/citadel/domain.c
+++ b/citadel/domain.c
@@ -8,6 +8,34 @@
 
 #define SMART_HOST	"gatekeeper.wdcs.com"
 
+/*
+ * sort_mxrecs()
+ *
+ * Sort a pile of MX records (struct mx, definted in domain.h) by preference
+ *
+ */
+void sort_mxrecs(struct mx *mxrecs, int num_mxrecs) {
+	int a, b;
+	struct mx hold1, hold2;
+
+	if (num_mxrecs < 2) return;
+
+	/* do the sort */
+	for (a = num_mxrecs - 2; a >= 0; --a) {
+		for (b = 0; b <= a; ++b) {
+			if (mxrecs[b].pref > mxrecs[b+1].pref) {
+
+				memcpy(hold1, mxrefs[b], sizeof(struct mx));
+				memcpy(hold2, mxrefs[b+1], sizeof(struct mx));
+				memcpy(mxrefs[b], hold2, sizeof(struct mx));
+				memcpy(mxrefs[b+1], hold1, sizeof(struct mx));
+			}
+		}
+	}
+}
+
+
+
 /* 
  * getmx()
  *
@@ -26,12 +54,16 @@ int getmx(char *mxbuf, char *dest) {
 	char expanded_buf[1024];
 	unsigned short pref, type;
 	int n;
+	HEADER *hp;
+	int qdcount;
 
+	struct mx *mxrecs = NULL;
+	int num_mxrecs = 0;
 
 	/* If we're configured to send all mail to a smart-host, then our
 	 * job here is really easy.
 	 */
-	if (1) {	/* FIX */
+	if (0) {	/* FIX */
 		strcpy(mxbuf, SMART_HOST);
 		return(1);
 	}
@@ -40,9 +72,7 @@ int getmx(char *mxbuf, char *dest) {
 	 */
 	ret = res_query(
 		dest,
-		C_IN, T_MX, answer, sizeof(answer)  );
-
-	lprintf(9, "res_query() returned %d\n", ret);
+		C_IN, T_MX, (unsigned char *)answer, sizeof(answer)  );
 
 	if (ret < 0) {
 		lprintf(5, "No MX found\n");
@@ -52,13 +82,19 @@ int getmx(char *mxbuf, char *dest) {
 	/* If we had to truncate, shrink the number to avoid fireworks */
 	if (ret > sizeof(answer))
 		ret = sizeof(answer);
-	lprintf(9, "size of answer is %d\n", ret);
 
+	hp = (HEADER *)&answer[0];
 	startptr = &answer[0];		/* start and end of buffer */
 	endptr = &answer[ret];
-
 	ptr = startptr + HFIXEDSZ;	/* advance past header */
 
+	for (qdcount = ntohs(hp->qdcount); qdcount--; ptr += ret + QFIXEDSZ) {
+		if ((ret = dn_skipname(ptr, endptr)) < 0) {
+			lprintf(9, "dn_skipname error\n");
+			return(0);
+		}
+	}
+
 	while(1) {
 		memset(expanded_buf, 0, sizeof(expanded_buf));
 		ret = dn_expand(startptr,
@@ -73,23 +109,48 @@ int getmx(char *mxbuf, char *dest) {
 		GETSHORT(type, ptr);
 		ptr += INT16SZ + INT32SZ;
 		GETSHORT(n, ptr);
-		ptr += n;
 
-		lprintf(9, "ret=%d, type=%d\n", ret, type);
+		if (type != T_MX) {
+			ptr += n;
+		}
+
+		else {
+			GETSHORT(pref, ptr);
+			ret = dn_expand(startptr,
+					endptr,
+					ptr,
+					expanded_buf,
+					sizeof(expanded_buf)
+					);
+			ptr += ret;
+
+			++num_mxrecs;
+			if (mxrecs == NULL) {
+				mxrecs = mallok(sizeof(struct mx));
+			}
+			else {
+				mxrecs = reallok(mxrecs,
+					(sizeof(struct mx) * num_mxrecs) );
+			}
+
+			mxrecs[num_mxrecs - 1].pref = pref;
+			strcpy(mxrecs[num_mxrecs - 1].host, expanded_buf);
+		}
 	}
 
-
-
-
-
-
-
-
-
-
-
-
-
-	/* FIX not done yet */
-	return(0);
+	lprintf(9, "unsorted...\n");
+	for (n=0; n<num_mxrecs; ++n)
+		lprintf(9, "%10d %s\n", mxrecs[n].pref, mxrecs[n].host);
+	sort_mxrecs(mxrecs, num_mxrecs);
+	lprintf(9, "sorted...\n");
+	for (n=0; n<num_mxrecs; ++n)
+		lprintf(9, "%10d %s\n", mxrecs[n].pref, mxrecs[n].host);
+
+	strcpy(mxbuf, "");
+	for (n=0; n<num_mxrecs; ++n) {
+		strcat(mxbuf, mxrecs[n].host);
+		strcat(mxbuf, "|");
+	}
+	phree(mxrecs);
+	return(num_msrecs);
 }
diff --git a/citadel/domain.h b/citadel/domain.h
index 10d17be0f..b20941725 100644
--- a/citadel/domain.h
+++ b/citadel/domain.h
@@ -1 +1,7 @@
+
+struct mx {
+	int pref;
+	char host[1024];
+};
+
 int getmx(char *mxbuf, char *dest);
-- 
2.39.2