proxy: fix inspector with mcp.internal() responses

mcp.internal's result lines are in r->cresp->wbuf referenced into an
iov, not r->buf. This fix checks for where the res line is before
attempting to reference it.

proxy_inspector.c

@@ -70,6 +70,8 @@ struct mcp_inspector {
 
 // PRIVATE INTERFACE
 
+#define res_buf(r) (r->cresp ? r->cresp->iov[0].iov_base : r->buf)
+
 // COMMON ARG HANDLERS
 
 // multiple step types only take 'flag' as an argument.
@@ -311,7 +313,7 @@ static int mcp_inspector_hasflag_r(lua_State *L, struct mcp_inspector *ins, stru
             // result object may not be tokenized. this will do so if not
             // already. any future hits agains the same object will use the
             // cached tokenizer struct.
-            mcmc_tokenize_res(res->buf, res->resp.reslen, &res->tok);
+            mcmc_tokenize_res(res_buf(res), res->resp.reslen, &res->tok);
             if (mcmc_token_has_flag_bit(&res->tok, c->bit) == MCMC_OK) {
                 lua_pushboolean(L, 1);
             } else {
@@ -341,11 +343,11 @@ static int mcp_inspector_flagtoken_r(lua_State *L, struct mcp_inspector *ins, st
     } else {
         mcp_resp_t *res = arg;
         if (res->resp.type == MCMC_RESP_META) {
-            mcmc_tokenize_res(res->buf, res->resp.reslen, &res->tok);
+            mcmc_tokenize_res(res_buf(res), res->resp.reslen, &res->tok);
             if (mcmc_token_has_flag_bit(&res->tok, c->bit) == MCMC_OK) {
                 lua_pushboolean(L, 1); // flag exists
                 int tlen = 0;
-                const char *tok = mcmc_token_get_flag(res->buf, &res->tok, c->f, &tlen);
+                const char *tok = mcmc_token_get_flag(res_buf(res), &res->tok, c->f, &tlen);
                 lua_pushlstring(L, tok, tlen); // flag's token
                 return 2;
             }
@@ -377,11 +379,11 @@ static int mcp_inspector_flagint_r(lua_State *L, struct mcp_inspector *ins, stru
     } else {
         mcp_resp_t *res = arg;
         if (res->resp.type == MCMC_RESP_META) {
-            mcmc_tokenize_res(res->buf, res->resp.reslen, &res->tok);
+            mcmc_tokenize_res(res_buf(res), res->resp.reslen, &res->tok);
             if (mcmc_token_has_flag_bit(&res->tok, c->bit) == MCMC_OK) {
                 lua_pushboolean(L, 1); // flag exists
                 int64_t tok = 0;
-                if (mcmc_token_get_flag_64(res->buf, &res->tok, c->f, &tok) == MCMC_OK) {
+                if (mcmc_token_get_flag_64(res_buf(res), &res->tok, c->f, &tok) == MCMC_OK) {
                     lua_pushinteger(L, tok);
                 } else {
                     lua_pushnil(L); // token couldn't be converted
@@ -451,11 +453,11 @@ static int mcp_inspector_flagis_r(lua_State *L, struct mcp_inspector *ins, struc
     } else {
         mcp_resp_t *res = arg;
         if (res->resp.type == MCMC_RESP_META) {
-            mcmc_tokenize_res(res->buf, res->resp.reslen, &res->tok);
+            mcmc_tokenize_res(res_buf(res), res->resp.reslen, &res->tok);
             if (mcmc_token_has_flag_bit(&res->tok, c->bit) == MCMC_OK) {
                 lua_pushboolean(L, 1); // flag exists
                 int tlen = 0;
-                const char *tok = mcmc_token_get_flag(res->buf, &res->tok, c->f, &tlen);
+                const char *tok = mcmc_token_get_flag(res_buf(res), &res->tok, c->f, &tlen);
                 if (tlen == c->len && strncmp(tok, str, c->len) == 0) {
                     lua_pushboolean(L, 1);
                 } else {

t/proxyins.lua

@@ -132,10 +132,25 @@ function mcp_config_routes(p)
         end
     })
 
+    local mgintres = mcp.funcgen_new()
+    -- no handle: using mcp.internal()
+    mgintres:ready({
+        n = "intres", f = function(rctx)
+            return function(r)
+                --local key = r:key()
+                local res = mcp.internal(r)
+                local has_O, O, has_t, t = mgresflaga_ins(res)
+                return string.format("SERVER_ERROR O[%q]: %s t[%q]: %q\r\n",
+                    has_O, O, has_t, t)
+            end
+        end
+    })
+
     local mgr = mcp.router_new({ map = {
         sepkey = mgsepkey,
         reshasf = mgreshasf,
         reqkey = mgreqkey,
+        intres = mgintres,
     }})
     mcp.attach(mcp.CMD_MG, mgr)
 end

t/proxyins.t

@@ -30,8 +30,23 @@ print $w "watch proxyevents\r\n";
 is(<$w>, "OK\r\n");
 
 {
-    test_mgreq();
-    test_mgres();
+    test_mgintres();
+    #test_mgreq();
+    #test_mgres();
+}
+
+sub test_mgintres {
+    'note testing mcp.internal()';
+    $t->c_send("ms intres/tokenint 5 F5\r\n");
+    $t->c_send("hello\r\n");
+    $t->c_recv("HD\r\n");
+    $t->clear();
+
+    subtest 'flagtoken and flagint' => sub {
+        $t->c_send("mg intres/tokenint f t s Omoo\r\n");
+        $t->c_recv("SERVER_ERROR O[true]: moo t[true]: -1\r\n");
+        $t->clear();
+    };
 }
 
 sub test_mgreq {