Multiple Connection Support

[dccp2tcp] / connections.c

diff --git a/connections.c b/connections.c
new file mode 100644 (file)
index 0000000..511692f
--- /dev/null
+++ b/connections.c
@@ -0,0 +1,91 @@
+/******************************************************************************
+Author: Samuel Jero
+
+Date: 7/2011
+
+Description: Functions for differentiating different DCCP connections.
+
+******************************************************************************/
+#include "dccp2tcp.h"
+
+/*Lookup a connection. If it doesn't exist, add a new connection and return it.*/
+int get_host(uint32_t src_id, uint32_t dest_id, int src_port, int dest_port, struct host *fwd, struct host *rev){
+       struct connection *ptr;
+
+       /*Empty list*/
+       if(chead==NULL){
+               if(add_connection(src_id, dest_id, src_port, dest_port)==NULL){
+                       return 1;
+               }
+               fwd=&chead->A;
+               rev=&chead->B;
+               return 0;
+       }
+
+       /*Loop list looking for connection*/
+       ptr=chead;
+       while(ptr!=NULL){
+               if(ptr->A.id==src_id && ptr->A.port==src_port && ptr->A.state!=CLOSE){
+                       fwd=&ptr->A;
+                       rev=&ptr->B;
+                       return 0;
+               }
+               if(ptr->B.id==src_id && ptr->B.port==src_port && ptr->B.state!=CLOSE){
+                       fwd=&ptr->B;
+                       rev=&ptr->A;
+                       return 0;
+               }
+               ptr=ptr->next;
+       }
+
+       /*Add new connection*/
+       ptr=add_connection(src_id, dest_id, src_port, dest_port);
+       if(ptr==NULL){
+               return 1;
+       }
+       fwd=&ptr->A;
+       rev=&ptr->B;
+       return 0;
+}
+
+/*Add a connection. Return it. On failure, return NULL*/
+struct connection *add_connection(uint32_t src_id, uint32_t dest_id, int src_port, int dest_port){
+       struct connection *ptr;
+       struct connection *prev;
+
+       /*Allocate memory*/
+       if(chead){
+               ptr=chead=malloc(sizeof(struct connection));
+       }else{
+               ptr=chead;
+               prev=chead;
+               while(ptr!=NULL){
+                       prev=ptr;
+                       ptr=ptr->next;
+               }
+               ptr=prev->next=malloc(sizeof(struct connection));
+       }
+
+       if(ptr==NULL){
+               dbgprintf(0,"Error: Couldn't allocate Memory\n");
+               exit(1);
+       }
+
+       /*Initialize*/
+       ptr->A.id=src_id;
+       ptr->A.state=INIT;
+       ptr->B.id=dest_id;
+       ptr->B.port=dest_port;
+       ptr->B.state=INIT;
+
+       return ptr;
+}
+
+/*Update the state on a host*/
+int update_state(struct host* hst, enum con_state st){
+       if(!hst){
+               return 1;
+       }
+       hst->state=st;
+       return 0;
+}