Separate backend_send from backend_sendbuffer.

On a similar theme of separating the query operation from the
attempted change, backend_send() now no longer has the side effect of
returning the current size of the send buffer. Instead, you have to
call backend_sendbuffer() every time you want to know that.

otherbackends/raw.c

@@ -207,16 +207,14 @@ static void raw_reconfig(Backend *be, Conf *conf)
 /*
  * Called to send data down the raw connection.
  */
-static size_t raw_send(Backend *be, const char *buf, size_t len)
+static void raw_send(Backend *be, const char *buf, size_t len)
 {
     Raw *raw = container_of(be, Raw, backend);
 
     if (raw->s == NULL)
-        return 0;
+        return;
 
     raw->bufsize = sk_write(raw->s, buf, len);
-
-    return raw->bufsize;
 }
 
 /*

otherbackends/rlogin.c

@@ -269,13 +269,13 @@ static void rlogin_reconfig(Backend *be, Conf *conf)
 /*
  * Called to send data down the rlogin connection.
  */
-static size_t rlogin_send(Backend *be, const char *buf, size_t len)
+static void rlogin_send(Backend *be, const char *buf, size_t len)
 {
     Rlogin *rlogin = container_of(be, Rlogin, backend);
     bufchain bc;
 
     if (rlogin->s == NULL)
-        return 0;
+        return;
 
     bufchain_init(&bc);
     bufchain_add(&bc, buf, len);
@@ -305,8 +305,6 @@ static size_t rlogin_send(Backend *be, const char *buf, size_t len)
     }
 
     bufchain_clear(&bc);
-
-    return rlogin->bufsize;
 }
 
 /*

otherbackends/supdup.c

@@ -797,14 +797,14 @@ static void supdup_reconfig(Backend *be, Conf *conf)
 /*
 * Called to send data down the Supdup connection.
 */
-static size_t supdup_send(Backend *be, const char *buf, size_t len)
+static void supdup_send(Backend *be, const char *buf, size_t len)
 {
     Supdup *supdup = container_of(be, Supdup, backend);
     char c;
     int i;
 
     if (supdup->s == NULL)
-        return 0;
+        return;
 
     for (i = 0; i < len; i++) {
         if (buf[i] == 034)
@@ -814,7 +814,6 @@ static size_t supdup_send(Backend *be, const char *buf, size_t len)
             supdup->bufsize = sk_write(supdup->s, &c, 1);
         }
     }
-    return supdup->bufsize;
 }
 
 /*

otherbackends/telnet.c

@@ -813,7 +813,7 @@ static void telnet_reconfig(Backend *be, Conf *conf)
 /*
  * Called to send data down the Telnet connection.
  */
-static size_t telnet_send(Backend *be, const char *buf, size_t len)
+static void telnet_send(Backend *be, const char *buf, size_t len)
 {
     Telnet *telnet = container_of(be, Telnet, backend);
     unsigned char *p, *end;
@@ -824,7 +824,7 @@ static size_t telnet_send(Backend *be, const char *buf, size_t len)
 #endif
 
     if (telnet->s == NULL)
-        return 0;
+        return;
 
     p = (unsigned char *)buf;
     end = (unsigned char *)(buf + len);
@@ -841,8 +841,6 @@ static size_t telnet_send(Backend *be, const char *buf, size_t len)
             p++;
         }
     }
-
-    return telnet->bufsize;
 }
 
 /*

otherbackends/testback.c

@@ -39,9 +39,10 @@ static char *loop_init(const BackendVtable *, Seat *, Backend **, LogContext *,
 static void null_free(Backend *);
 static void loop_free(Backend *);
 static void null_reconfig(Backend *, Conf *);
-static size_t null_send(Backend *, const char *, size_t);
-static size_t loop_send(Backend *, const char *, size_t);
+static void null_send(Backend *, const char *, size_t);
+static void loop_send(Backend *, const char *, size_t);
 static size_t null_sendbuffer(Backend *);
+static size_t loop_sendbuffer(Backend *);
 static void null_size(Backend *, int, int);
 static void null_special(Backend *, SessionSpecialCode, int);
 static const SessionSpecial *null_get_specials(Backend *);
@@ -80,7 +81,7 @@ const BackendVtable loop_backend = {
     .free = loop_free,
     .reconfig = null_reconfig,
     .send = loop_send,
-    .sendbuffer = null_sendbuffer,
+    .sendbuffer = loop_sendbuffer,
     .size = null_size,
     .special = null_special,
     .get_specials = null_get_specials,
@@ -100,6 +101,7 @@ const BackendVtable loop_backend = {
 struct loop_state {
     Seat *seat;
     Backend backend;
+    size_t sendbuffer;
 };
 
 static char *null_init(const BackendVtable *vt, Seat *seat,
@@ -143,15 +145,14 @@ static void null_reconfig(Backend *be, Conf *conf) {
 
 }
 
-static size_t null_send(Backend *be, const char *buf, size_t len) {
+static void null_send(Backend *be, const char *buf, size_t len) {
 
-    return 0;
 }
 
-static size_t loop_send(Backend *be, const char *buf, size_t len) {
+static void loop_send(Backend *be, const char *buf, size_t len) {
     struct loop_state *st = container_of(be, struct loop_state, backend);
 
-    return seat_output(st->seat, 0, buf, len);
+    st->sendbuffer = seat_output(st->seat, 0, buf, len);
 }
 
 static size_t null_sendbuffer(Backend *be) {
@@ -159,6 +160,12 @@ static size_t null_sendbuffer(Backend *be) {
     return 0;
 }
 
+static size_t loop_sendbuffer(Backend *be) {
+    struct loop_state *st = container_of(be, struct loop_state, backend);
+
+    return st->sendbuffer;
+}
+
 static void null_size(Backend *be, int width, int height) {
 
 }