Only memcpy as much as we need to when we need to.

[netwatch.git] / net / rfb.c

diff --git a/net/rfb.c b/net/rfb.c
index ff0f0895b6bff8548b5c81c7a8263e3d703e6316..1f620f0dcec9d8354f7a049f31a7044eac857472 100644 (file)
--- a/net/rfb.c
+++ b/net/rfb.c
@@ -164,8 +164,7 @@ static void send_fsm(struct tcp_pcb *pcb, struct rfb_state *state) {
                        break;
                }
        
-               /* potential FALL THROUGH */
-
+               /* FALL THROUGH to SST_NEEDS_UPDATE*/
        case SST_NEEDS_UPDATE:
                outputf("RFB send: sending header");
                /* Send a header */
@@ -182,13 +181,9 @@ static void send_fsm(struct tcp_pcb *pcb, struct rfb_state *state) {
                state->update_pos = 0;
                state->send_state = SST_SENDING;
 
-               /* FALL THROUGH */
-
+               /* FALL THROUGH to SST_SENDING*/
        case SST_SENDING:
-
                while (1) {
-                       unsigned char mbuf[8192 /* XXX magic */];
-                       
                        left = state->frame_bytes - state->update_pos;
 
                        if (left == 0) {
@@ -196,29 +191,21 @@ static void send_fsm(struct tcp_pcb *pcb, struct rfb_state *state) {
                                break;
                        }
                        
-                       if (left > 8192)
+                       if (left > 8192)        /* Sounds good enough to me. */
                                left = 8192;
 
-                       if (left > tcp_mss(pcb)) {
-                               sndlength = tcp_mss(pcb);
-                       } else {
-                               sndlength = left;
-                       }
-                       
-                       memcpy(mbuf, fb->fbaddr + state->update_pos, sndlength);        /* It's OK if it becomes smaller later. */
-
+                       sndlength = left;
                        do {
-                               err = tcp_write(pcb, mbuf, sndlength, TCP_WRITE_FLAG_COPY /* This is my memory on the stack, thank you very much. */);
-                               if (err == ERR_MEM) {
-                                       outputf("RFB: ERR_MEM sending %d", sndlength);
+                               err = tcp_write(pcb, fb->fbaddr + state->update_pos, sndlength, TCP_WRITE_FLAG_COPY /* The card can't DMA from there. */);
+                               if (err == ERR_MEM)             /* Back down until lwip says we've got space. */
                                        sndlength /= 2;
-                               }
                        } while (err == ERR_MEM && sndlength > 1);
 
-                       if (err == ERR_OK) {
-                               outputf("RFB: attempting send %d", sndlength);
-                       } else {
-                               outputf("RFB: send error %d", err);
+                       if (err != ERR_OK) {
+                               if (err != ERR_MEM)
+                                       outputf("RFB: send error %d", err);
+                               
+                               /* We'll just give up for now and come back when we have space later. */
                                break;
                        }
 
@@ -233,9 +220,7 @@ static void send_fsm(struct tcp_pcb *pcb, struct rfb_state *state) {
        }
        
        if (tcp_output(pcb) != ERR_OK)
-       {
                outputf("RFB: tcp_output bailed in send_fsm?");
-       }
 }
 
 static err_t rfb_sent(void *arg, struct tcp_pcb *pcb, uint16_t len) {
@@ -353,7 +338,6 @@ static enum fsm_result recv_fsm(struct tcp_pcb *pcb, struct rfb_state *state) {
                        for (i = 0; i < ntohs(req->num); i++) {
                                outputf("RFB: Encoding: %d", ntohl(req->encodings[i]));
                                /* XXX ... */
-
                        }
 
                        state->readpos += pktsize;
@@ -460,7 +444,7 @@ static err_t rfb_recv(void *arg, struct tcp_pcb *pcb,
                case OK:
                        outputf("RFB FSM: ok");
 
-                       /* Might as well send now... */
+                       /* Kick off a send. */
                        if (state->send_state == SST_IDLE
                            && state->update_requested) {
                                send_fsm(pcb, state);