date and time created 84/04/11 15:03:08 by karels

SCCS-vsn: libexec/talkd/process.c 1.1

diff --git a/usr/src/libexec/talkd/process.c b/usr/src/libexec/talkd/process.c
new file mode 100644 (file)
index 0000000..0075354
--- /dev/null
+++ b/usr/src/libexec/talkd/process.c
@@ -0,0 +1,155 @@
+/* $Header: process.c 1.5 83/03/28 20:16:07 moore Exp $ */
+
+    /* process.c handles the requests, which can be of three types:
+
+               ANNOUNCE - announce to a user that a talk is wanted
+
+               LEAVE_INVITE - insert the request into the table
+               
+               LOOK_UP - look up to see if a request is waiting in
+                         in the table for the local user
+
+               DELETE - delete invitation
+
+     */
+
+#include "ctl.h"
+char *strcpy();
+CTL_MSG *find_request();
+CTL_MSG *find_match();
+
+process_request(request, response)
+CTL_MSG *request;
+CTL_RESPONSE *response;
+{
+    CTL_MSG *ptr;
+
+    response->type = request->type;
+    response->id_num = 0;
+
+    switch (request->type) {
+
+       case ANNOUNCE :
+
+           do_announce(request, response);
+           break;
+
+       case LEAVE_INVITE :
+
+           ptr = find_request(request);
+           if (ptr != (CTL_MSG *) 0) {
+               response->id_num = ptr->id_num;
+               response->answer = SUCCESS;
+           } else {
+               insert_table(request, response);
+           }
+           break;
+
+       case LOOK_UP :
+
+           ptr = find_match(request);
+           if (ptr != (CTL_MSG *) 0) {
+               response->id_num = ptr->id_num;
+               response->addr = ptr->addr;
+               response->answer = SUCCESS;
+           } else {
+               response->answer = NOT_HERE;
+           }
+           break;
+
+       case DELETE :
+
+           response->answer = delete_invite(request->id_num);
+           break;
+
+       default :
+
+           response->answer = UNKNOWN_REQUEST;
+           break;
+
+    }
+}
+
+struct hostent *gethostbyaddr();
+
+do_announce(request, response)
+CTL_MSG *request;
+CTL_RESPONSE *response;
+{
+    struct hostent *hp;
+    CTL_MSG *ptr;
+    int result;
+
+       /* see if the user is logged */
+
+    result = find_user(request->r_name, request->r_tty);
+
+    if (result != SUCCESS) {
+       response->answer = result;
+       return;
+    }
+
+    hp = gethostbyaddr(&request->ctl_addr.sin_addr,
+                         sizeof(struct in_addr), AF_INET);
+
+    if ( hp == (struct hostent *) 0 ) {
+       response->answer = MACHINE_UNKNOWN;
+       return;
+    }
+
+    ptr = find_request(request);
+    if (ptr == (CTL_MSG *) 0) {
+       insert_table(request,response);
+       response->answer = announce(request, hp->h_name);
+    } else if (request->id_num > ptr->id_num) {
+           /*
+            * this is an explicit re-announce, so update the id_num
+            * field to avoid duplicates and re-announce the talk 
+            */
+       ptr->id_num = response->id_num = new_id();
+       response->answer = announce(request, hp->h_name);
+    } else {
+           /* a duplicated request, so ignore it */
+       response->id_num = ptr->id_num;
+       response->answer = SUCCESS;
+    }
+
+    return;
+}
+
+#include <utmp.h>
+
+/*
+ * Search utmp for the local user
+ */
+
+find_user(name, tty)
+char *name;
+char *tty;
+{
+    struct utmp ubuf;
+
+    int fd;
+
+    if ((fd = open("/etc/utmp", 0)) == -1) {
+       print_error("Can't open /etc/utmp");
+       return(FAILED);
+    }
+
+    while (read(fd, (char *) &ubuf, sizeof ubuf) == sizeof(ubuf)) {
+       if (strncmp(ubuf.ut_name, name, sizeof ubuf.ut_name) == 0) {
+           if (*tty == '\0') {
+                   /* no particular tty was requested */
+               (void) strcpy(tty, ubuf.ut_line);
+               close(fd);
+               return(SUCCESS);
+           } else if (strcmp(ubuf.ut_line, tty) == 0) {
+               close(fd);
+               return(SUCCESS);
+           }
+       }
+    }
+
+    close(fd);
+    return(NOT_HERE);
+}