BUG/MINOR: lua/htx: Respect the reserve when data are send from an HTX applet

In the function hlua_applet_htx_send_yield(), there already was a test to
respect the reserve but the wrong function was used to get the available space
for data in the HTX buffer. Instead of calling htx_free_space(), the function
htx_free_data_space() must be used. But in fact, there is no reason to bother
with that anymore because the function channel_htx_recv_max() has been added for
this purpose.

The result of this bug is that the call to htx_add_data() failed unexpectedly
while the amount of written data was incremented, leading the applet to think
all data was sent. To prevent any futher bugs, a test has been added to yield if
we are not able to write data into the channel buffer.

This patch must be backported to 1.9.

diff --git a/src/hlua.c b/src/hlua.c
index ca51477c4bca9cc368ca4d8585d092f18be3f479..b9df9265fb7c022a1f3f6d7d788f93e1845738c9 100644 (file)
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -4622,14 +4622,9 @@ __LJMP static int hlua_applet_htx_send_yield(lua_State *L, int status, lua_KCont
        int l = MAY_LJMP(luaL_checkinteger(L, 3));
        int max;
 
-       max = htx_free_space(htx);
-        if (channel_recv_limit(res) < b_size(&res->buf)) {
-                if (max < global.tune.maxrewrite) {
-                       si_rx_room_blk(si);
-                       MAY_LJMP(hlua_yieldk(L, 0, 0, hlua_applet_htx_send_yield, TICK_ETERNITY, 0));
-               }
-                max -= global.tune.maxrewrite;
-        }
+       max = channel_htx_recv_max(res, htx);
+       if (!max)
+               goto snd_yield;
 
        data = MAY_LJMP(luaL_checklstring(L, 2, &len));
 
@@ -4638,8 +4633,9 @@ __LJMP static int hlua_applet_htx_send_yield(lua_State *L, int status, lua_KCont
                max = len - l;
 
        /* Copy data. */
-       htx_add_data(htx, ist2(data + l, max));
-       res->total += l;
+       if (!htx_add_data(htx, ist2(data + l, max)))
+               goto snd_yield;
+       res->total += max;
        res->flags |= CF_READ_PARTIAL;
        htx_to_buf(htx, &res->buf);
 
@@ -4652,6 +4648,7 @@ __LJMP static int hlua_applet_htx_send_yield(lua_State *L, int status, lua_KCont
         * applet, and returns a yield.
         */
        if (l < len) {
+         snd_yield:
                si_rx_room_blk(si);
                MAY_LJMP(hlua_yieldk(L, 0, 0, hlua_applet_htx_send_yield, TICK_ETERNITY, 0));
        }