+ citnntp *nntpstate = (citnntp *) CC->session_specific_data;
+ char which_command[16];
+ int acmd = 0;
+ char requested_article[256];
+ long requested_msgnum = 0;
+ char *lb, *rb = NULL;
+ int must_change_currently_selected_article = 0;
+
+ // We're going to store one of these values in the variable 'acmd' so that
+ // we can quickly check later which version of the output we want.
+ enum {
+ ARTICLE,
+ HEAD,
+ BODY,
+ STAT
+ };
+
+ extract_token(which_command, cmd, 0, ' ', sizeof which_command);
+
+ if (!strcasecmp(which_command, "article")) {
+ acmd = ARTICLE;
+ }
+ else if (!strcasecmp(which_command, "head")) {
+ acmd = HEAD;
+ }
+ else if (!strcasecmp(which_command, "body")) {
+ acmd = BODY;
+ }
+ else if (!strcasecmp(which_command, "stat")) {
+ acmd = STAT;
+ }
+ else {
+ cprintf("500 I'm afraid I can't do that.\r\n");
+ return;
+ }
+
+ // Which NNTP command was issued, determines whether we will fetch headers, body, or both.
+ int headers_only = HEADERS_ALL;
+ if (acmd == HEAD) headers_only = HEADERS_FAST;
+ else if (acmd == BODY) headers_only = HEADERS_NONE;
+ else if (acmd == STAT) headers_only = HEADERS_FAST;
+
+ // now figure out what the client is asking for.
+ extract_token(requested_article, cmd, 1, ' ', sizeof requested_article);
+ lb = strchr(requested_article, '<');
+ rb = strchr(requested_article, '>');
+ requested_msgnum = atol(requested_article);
+
+ // If no article number or message-id is specified, the client wants the "currently selected article"
+ if (IsEmptyStr(requested_article)) {
+ if (nntpstate->current_article_number < 1) {
+ cprintf("420 No current article selected\r\n");
+ return;
+ }
+ requested_msgnum = nntpstate->current_article_number;
+ must_change_currently_selected_article = 1;
+ // got it -- now fall through and keep going
+ }
+
+ // If the requested article is numeric, it maps directly to a message number. Good.
+ else if (requested_msgnum > 0) {
+ must_change_currently_selected_article = 1;
+ // good -- fall through and keep going
+ }
+
+ // If the requested article has angle brackets, the client wants a specific message-id.
+ // We don't know how to do that yet.
+ else if ( (lb != NULL) && (rb != NULL) && (lb < rb) ) {
+ must_change_currently_selected_article = 0;
+ cprintf("500 I don't know how to fetch by message-id yet.\r\n"); // FIXME
+ return;
+ }
+
+ // Anything else is noncompliant gobbledygook and should die in a car fire.
+ else {
+ must_change_currently_selected_article = 0;
+ cprintf("500 syntax error\r\n");
+ return;
+ }
+
+ // At this point we know the message number of the "article" being requested.
+ // We have an awesome API call that does all the heavy lifting for us.
+ char *fetched_message_id = NULL;
+ CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
+ int fetch = CtdlOutputMsg(requested_msgnum,
+ MT_RFC822, // output in RFC822 format ... sort of
+ headers_only, // headers, body, or both?
+ 0, // don't do Citadel protocol responses
+ 1, // CRLF newlines
+ NULL, // teh whole thing, not just a section
+ 0, // no flags yet ... maybe new ones for Path: etc ?
+ NULL,
+ NULL,
+ &fetched_message_id // extract the message ID from the message as we go...
+ );
+ StrBuf *msgtext = CC->redirect_buffer;
+ CC->redirect_buffer = NULL;
+
+ if (fetch != om_ok) {
+ cprintf("423 no article with that number\r\n");
+ FreeStrBuf(&msgtext);
+ return;
+ }
+
+ // RFC3977 6.2.1.2 specifes conditions under which the "currently selected article"
+ // MUST or MUST NOT be set to the message we just referenced.
+ if (must_change_currently_selected_article) {
+ nntpstate->current_article_number = requested_msgnum;
+ }
+
+ // Now give the client what it asked for.
+ if (acmd == ARTICLE) {
+ cprintf("220 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
+ }
+ if (acmd == HEAD) {
+ cprintf("221 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
+ }
+ if (acmd == BODY) {
+ cprintf("222 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
+ }
+ if (acmd == STAT) {
+ cprintf("223 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
+ FreeStrBuf(&msgtext);
+ return;
+ }
+
+ client_write(SKEY(msgtext));
+ cprintf(".\r\n"); // this protocol uses a dot terminator
+ FreeStrBuf(&msgtext);
+ if (fetched_message_id) free(fetched_message_id);
+}
+
+
+//
+// Utility function for nntp_last_next() that turns a msgnum into a message ID.
+// The memory for the returned string is pwnz0red by the caller.
+//
+char *message_id_from_msgnum(long msgnum) {
+ char *fetched_message_id = NULL;
+ CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
+ CtdlOutputMsg(msgnum,
+ MT_RFC822, // output in RFC822 format ... sort of
+ HEADERS_FAST, // headers, body, or both?
+ 0, // don't do Citadel protocol responses
+ 1, // CRLF newlines
+ NULL, // teh whole thing, not just a section
+ 0, // no flags yet ... maybe new ones for Path: etc ?
+ NULL,
+ NULL,
+ &fetched_message_id // extract the message ID from the message as we go...
+ );
+ StrBuf *msgtext = CC->redirect_buffer;
+ CC->redirect_buffer = NULL;
+
+ FreeStrBuf(&msgtext);
+ return(fetched_message_id);
+}
+
+
+//
+// The LAST and NEXT commands are so similar that they are handled by a single function.
+//
+void nntp_last_next(const char *cmd) {
+ if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
+
+ citnntp *nntpstate = (citnntp *) CC->session_specific_data;
+ char which_command[16];
+ int acmd = 0;
+
+ // We're going to store one of these values in the variable 'acmd' so that
+ // we can quickly check later which version of the output we want.
+ enum {
+ NNTP_LAST,
+ NNTP_NEXT
+ };
+
+ extract_token(which_command, cmd, 0, ' ', sizeof which_command);
+
+ if (!strcasecmp(which_command, "last")) {
+ acmd = NNTP_LAST;
+ }
+ else if (!strcasecmp(which_command, "next")) {
+ acmd = NNTP_NEXT;
+ }
+ else {
+ cprintf("500 I'm afraid I can't do that.\r\n");
+ return;
+ }
+
+ // ok, here we go ... fetch the msglist so we can figure out our place in the universe
+ struct nntp_msglist nm;
+ int i = 0;
+ long selected_msgnum = 0;
+ char *message_id = NULL;
+
+ nm = nntp_fetch_msglist(&CC->room);
+ if ((nm.num_msgs < 0) || (nm.msgnums == NULL)) {
+ cprintf("500 something bad happened\r\n");
+ return;
+ }
+
+ if ( (acmd == NNTP_LAST) && (nm.num_msgs == 0) ) {
+ cprintf("422 no previous article in this group\r\n"); // nothing here
+ }
+
+ else if ( (acmd == NNTP_LAST) && (nntpstate->current_article_number <= nm.msgnums[0]) ) {
+ cprintf("422 no previous article in this group\r\n"); // already at the beginning
+ }
+
+ else if (acmd == NNTP_LAST) {
+ for (i=0; ((i<nm.num_msgs)&&(selected_msgnum<=0)); ++i) {
+ if ( (nm.msgnums[i] >= nntpstate->current_article_number) && (i > 0) ) {
+ selected_msgnum = nm.msgnums[i-1];
+ }
+ }
+ if (selected_msgnum > 0) {
+ nntpstate->current_article_number = selected_msgnum;
+ message_id = message_id_from_msgnum(nntpstate->current_article_number);
+ cprintf("223 %ld <%s>\r\n", nntpstate->current_article_number, message_id);
+ if (message_id) free(message_id);
+ }
+ else {
+ cprintf("422 no previous article in this group\r\n");
+ }
+ }
+
+ else if ( (acmd == NNTP_NEXT) && (nm.num_msgs == 0) ) {
+ cprintf("421 no next article in this group\r\n"); // nothing here
+ }
+
+ else if ( (acmd == NNTP_NEXT) && (nntpstate->current_article_number >= nm.msgnums[nm.num_msgs-1]) ) {
+ cprintf("421 no next article in this group\r\n"); // already at the end
+ }
+
+ else if (acmd == NNTP_NEXT) {
+ for (i=0; ((i<nm.num_msgs)&&(selected_msgnum<=0)); ++i) {
+ if (nm.msgnums[i] > nntpstate->current_article_number) {
+ selected_msgnum = nm.msgnums[i];
+ }
+ }
+ if (selected_msgnum > 0) {
+ nntpstate->current_article_number = selected_msgnum;
+ message_id = message_id_from_msgnum(nntpstate->current_article_number);
+ cprintf("223 %ld <%s>\r\n", nntpstate->current_article_number, message_id);
+ if (message_id) free(message_id);
+ }
+ else {
+ cprintf("421 no next article in this group\r\n");
+ }
+ }
+
+ // should never get here
+ else {
+ cprintf("500 internal error\r\n");
+ }
+
+ if (nm.msgnums != NULL) {
+ free(nm.msgnums);
+ }
+
+}
+
+
+//
+// back end for the XOVER command , called for each message number
+//
+void nntp_xover_backend(long msgnum, void *userdata) {
+
+ struct listgroup_range *lr = (struct listgroup_range *)userdata;
+
+ // check range if supplied
+ if (msgnum < lr->lo) return;
+ if ((lr->hi != 0) && (msgnum > lr->hi)) return;
+
+ struct CtdlMessage *msg = CtdlFetchMessage(msgnum, 0);
+ if (msg == NULL) {
+ return;
+ }
+
+ // Teh RFC says we need:
+ // -------------------------
+ // Subject header content
+ // From header content
+ // Date header content
+ // Message-ID header content
+ // References header content
+ // :bytes metadata item
+ // :lines metadata item
+
+ time_t msgtime = atol(msg->cm_fields[eTimestamp]);
+ char strtimebuf[26];
+ ctime_r(&msgtime, strtimebuf);
+
+ // here we go -- print the line o'data
+ cprintf("%ld\t%s\t%s <%s>\t%s\t%s\t%s\t100\t10\r\n",
+ msgnum,
+ msg->cm_fields[eMsgSubject],
+ msg->cm_fields[eAuthor],
+ msg->cm_fields[erFc822Addr],
+ strtimebuf,
+ msg->cm_fields[emessageId],
+ msg->cm_fields[eWeferences]
+ );
+
+ CM_Free(msg);
+}
+
+
+//
+//
+// XOVER is used by some clients, even if we don't offer it
+//
+void nntp_xover(const char *cmd) {
+ if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
+
+ citnntp *nntpstate = (citnntp *) CC->session_specific_data;
+ char range[256];
+ struct listgroup_range lr;
+
+ extract_token(range, cmd, 1, ' ', sizeof range);
+ lr.lo = atol(range);
+ if (lr.lo <= 0) {
+ lr.lo = nntpstate->current_article_number;
+ lr.hi = nntpstate->current_article_number;
+ }
+ else {
+ char *dash = strchr(range, '-');
+ if (dash != NULL) {
+ ++dash;
+ lr.hi = atol(dash);
+ if (lr.hi == 0) {
+ lr.hi = LONG_MAX;
+ }
+ if (lr.hi < lr.lo) {
+ lr.hi = lr.lo;
+ }
+ }
+ else {
+ lr.hi = lr.lo;
+ }
+ }
+
+ cprintf("224 Overview information follows\r\n");
+ CtdlForEachMessage(MSGS_ALL, 0L, NULL, NULL, NULL, nntp_xover_backend, &lr);
+ cprintf(".\r\n");
+}
+
+
+//
+// Main command loop for NNTP server sessions.
+//
+void nntp_command_loop(void) {