include a linked list for recording each ptp source. Untested

diff --git a/nqptp.c b/nqptp.c
index 54ca06b06d6bab9b5ee89951003cf37276bf7f80..a9cde57c1b3c580c479710ce5ed2d1c9b06bfdd4 100644 (file)
--- a/nqptp.c
+++ b/nqptp.c
@@ -4,7 +4,7 @@
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 3.
+ * the Free Software Foundation, version 2.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -60,8 +60,13 @@ enum messageType {
   Reserved_F
 };
 
+typedef struct {
+       char *ip;  //ipv4 or ipv6
+       uint64_t t1,t2,t3,t4;
+       struct ptpSource *next;
+} ptpSource;
+
 #define BUFLEN 4096 // Max length of buffer
-#define PORT 320    // The port on which to listen for incoming data
 
 struct sockaddr_in si_me_319, si_me_320, si_other;
 
@@ -99,6 +104,39 @@ uint64_t get_time_now() {
   return timespec_to_ns(&tn);
 }
 
+ptpSource* findOrCreateSource(ptpSource** list, char *ip) {
+       ptpSource* response;
+       ptpSource** insertion_point = list; // in case the list is empty
+       ptpSource* crawler = *list;
+       if (crawler == NULL) {
+               insertion_point = list;
+       } else  {
+               while ((crawler->next != NULL) && (strcasecmp(ip,crawler->ip)!= 0)) {
+                       crawler = crawler->next;
+               }
+               if (strcasecmp(ip,crawler->ip)== 0) {
+                       // found, so no insertion
+                       insertion_point = NULL;
+               else
+                       // not found, so we are on the last item. Add a new one on to the end.
+                       insertion_point = &crawler->next;
+               }
+       }
+       // here, if the insertion point is null, then
+       // the record is pointer to by crawler
+       // otherwise, add a new record at the insertion point
+       if (insertion_point == NULL) {
+               response = crawler;
+       } else {
+               response = (ptpSource*)malloc(sizeof(ptpSource));
+               if (response != NULL) {
+                       memset((void *)response,0,sizeof(ptpSource));
+                       response->ip = strdup(ip);
+               }
+       }
+       return response;
+}
+
 void print_buffer(char *buf, size_t buf_len) {
   uint64_t time_now = get_time_now();
   if (time_then == 0) {
@@ -157,6 +195,8 @@ int main(void) {
   unsigned int slen = sizeof(si_other);
   ssize_t recv_len;
 
+  ptpSource *clocks = NULL; // a one-way linked list
+
   char buf[BUFLEN];
 
   int status;
@@ -284,6 +324,8 @@ int main(void) {
             -1) {
           die("recvfrom() 319");
         } else if (recv_len >= (ssize_t)sizeof(struct ptp_common_message_header)) {
+               // find or create a ptpSource record for this one.
+               ptpSource *the_clock = findOrCreateSource(clocks);
           // print_buffer(buf, recv_len);
           switch (buf[0] & 0xF) {
           case Sync: { // if it's a sync