Account for SPTPS overhead.

[meshlink] / src / utcp.c

diff --git a/src/utcp.c b/src/utcp.c
index 46d7fd35f065473f0baa1a27fe307ee8795eeebc..ca91bee26ef6d21c0f0f57dd743c27c0f9b14f8b 100644 (file)
--- a/src/utcp.c
+++ b/src/utcp.c
@@ -196,6 +196,16 @@ static bool buffer_wraps(struct buffer *buf) {
 }
 
 static bool buffer_resize(struct buffer *buf, uint32_t newsize) {
+       assert(!buf->external);
+
+       if(!newsize) {
+               free(buf->data);
+               buf->data = NULL;
+               buf->size = 0;
+               buf->offset = 0;
+               return true;
+       }
+
        char *newdata = realloc(buf->data, newsize);
 
        if(!newdata) {
@@ -441,17 +451,45 @@ static void set_buffer_storage(struct buffer *buf, char *data, size_t size) {
                buf->external = true;
        } else if(buf->external) {
                // Transition from external to internal buf
-               size_t minsize = buf->used < DEFAULT_SNDBUFSIZE ? DEFAULT_SNDBUFSIZE : buf->used;
-               data = malloc(minsize);
+               size_t minsize = buf->used <= DEFAULT_SNDBUFSIZE ? DEFAULT_SNDBUFSIZE : buf->used;
 
-               if(!data) {
-                       // Cannot handle this
-                       abort();
+               if(minsize) {
+                       data = malloc(minsize);
+
+                       if(!data) {
+                               // Cannot handle this
+                               abort();
+                       }
+
+                       buffer_transfer(buf, data, minsize);
+                       buf->data = data;
+               } else {
+                       buf->data = NULL;
+                       buf->size = 0;
                }
 
-               buffer_transfer(buf, data, minsize);
-               buf->data = data;
                buf->external = false;
+       } else {
+               // Don't do anything if the buffer wraps
+               if(buffer_wraps(buf)) {
+                       return;
+               }
+
+               // Realloc internal storage
+               size_t minsize = max(DEFAULT_SNDBUFSIZE, buf->offset + buf->used);
+
+               if(minsize) {
+                       data = realloc(buf->data, minsize);
+
+                       if(data) {
+                               buf->data = data;
+                               buf->size = minsize;
+                       }
+               } else {
+                       free(buf->data);
+                       buf->data = NULL;
+                       buf->size = 0;
+               }
        }
 }
 
@@ -1562,6 +1600,8 @@ synack:
                        // The peer has aborted our connection.
                        set_state(c, CLOSED);
                        errno = ECONNRESET;
+                       buffer_clear(&c->sndbuf);
+                       buffer_clear(&c->rcvbuf);
 
                        if(c->recv) {
                                c->recv(c, NULL, 0);
@@ -2034,8 +2074,8 @@ static bool reset_connection(struct utcp_connection *c) {
                return false;
        }
 
-       c->recv = NULL;
-       c->poll = NULL;
+       buffer_clear(&c->sndbuf);
+       buffer_clear(&c->rcvbuf);
 
        switch(c->state) {
        case CLOSED:
@@ -2068,6 +2108,7 @@ static bool reset_connection(struct utcp_connection *c) {
        hdr.ack = c->rcv.nxt;
        hdr.wnd = 0;
        hdr.ctl = RST;
+       hdr.aux = 0;
 
        print_packet(c, "send", &hdr, sizeof(hdr));
        c->utcp->send(c->utcp, &hdr, sizeof(hdr));
@@ -2075,21 +2116,16 @@ static bool reset_connection(struct utcp_connection *c) {
 }
 
 static void set_reapable(struct utcp_connection *c) {
-       if(c->sndbuf.external) {
-               set_buffer_storage(&c->sndbuf, NULL, DEFAULT_MTU);
-       }
-
-       if(c->rcvbuf.external) {
-               set_buffer_storage(&c->rcvbuf, NULL, DEFAULT_MTU);
-       }
+       set_buffer_storage(&c->sndbuf, NULL, min(c->sndbuf.maxsize, DEFAULT_MAXSNDBUFSIZE));
+       set_buffer_storage(&c->rcvbuf, NULL, min(c->rcvbuf.maxsize, DEFAULT_MAXRCVBUFSIZE));
 
        c->recv = NULL;
        c->poll = NULL;
        c->reapable = true;
 }
 
-// Closes all the opened connections
-void utcp_abort_all_connections(struct utcp *utcp) {
+// Resets all connections, but does not invalidate connection handles
+void utcp_reset_all_connections(struct utcp *utcp) {
        if(!utcp) {
                errno = EINVAL;
                return;
@@ -2102,19 +2138,16 @@ void utcp_abort_all_connections(struct utcp *utcp) {
                        continue;
                }
 
-               utcp_recv_t old_recv = c->recv;
-               utcp_poll_t old_poll = c->poll;
+               reset_connection(c);
 
-               utcp_abort(c);
-
-               if(old_recv) {
+               if(c->recv) {
                        errno = 0;
-                       old_recv(c, NULL, 0);
+                       c->recv(c, NULL, 0);
                }
 
-               if(old_poll && !c->reapable) {
+               if(c->poll && !c->reapable) {
                        errno = 0;
-                       old_poll(c, 0);
+                       c->poll(c, 0);
                }
        }
 
@@ -2171,6 +2204,8 @@ struct timespec utcp_timeout(struct utcp *utcp) {
                if(timespec_isset(&c->conn_timeout) && timespec_lt(&c->conn_timeout, &now)) {
                        errno = ETIMEDOUT;
                        c->state = CLOSED;
+                       buffer_clear(&c->sndbuf);
+                       buffer_clear(&c->rcvbuf);
 
                        if(c->recv) {
                                c->recv(c, NULL, 0);
@@ -2273,6 +2308,9 @@ void utcp_exit(struct utcp *utcp) {
                struct utcp_connection *c = utcp->connections[i];
 
                if(!c->reapable) {
+                       buffer_clear(&c->sndbuf);
+                       buffer_clear(&c->rcvbuf);
+
                        if(c->recv) {
                                c->recv(c, NULL, 0);
                        }