[PATCH] BUG/MEDIUM: lua: fix argument handling in data removal functions

[Boyang Li]

Lua API Channel.remove() and HTTPMessage.remove() expects 1 to 3
arguments (counting the manipulated object), with offset and length
being the 2nd and 3rd argument, respectively.

hlua_{channel,http_msg}_del_data() incorrectly gets the 3rd argument as
offset, and 4th (nonexistent) as length. hlua_http_msg_del_data() also
improperly checks arguments. This patch fixes argument handling in both.

Must be backported to 2.5.
---
 src/hlua.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/hlua.c b/src/hlua.c
index 05f3a9053..2327553c8 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -3714,8 +3714,8 @@ __LJMP static int hlua_channel_del_data(lua_State *L)
                WILL_LJMP(lua_error(L));
 
        offset = output;
-       if (lua_gettop(L) > 2) {
-               offset = MAY_LJMP(luaL_checkinteger(L, 3));
+       if (lua_gettop(L) > 1) {
+               offset = MAY_LJMP(luaL_checkinteger(L, 2));
                if (offset < 0)
                        offset = MAX(0, (int)input + offset);
                offset += output;
@@ -3726,8 +3726,8 @@ __LJMP static int hlua_channel_del_data(lua_State *L)
        }
 
        len = output + input - offset;
-       if (lua_gettop(L) == 4) {
-               len = MAY_LJMP(luaL_checkinteger(L, 4));
+       if (lua_gettop(L) == 3) {
+               len = MAY_LJMP(luaL_checkinteger(L, 3));
                if (!len)
                        goto end;
                if (len == -1)
@@ -6704,8 +6704,7 @@ __LJMP static int hlua_http_msg_del_data(lua_State *L)
        int offset, len;
 
        if (lua_gettop(L) < 1 || lua_gettop(L) > 3)
-               WILL_LJMP(luaL_error(L, "'insert' expects at most 2 
arguments"));
-       MAY_LJMP(check_args(L, 2, "insert"));
+               WILL_LJMP(luaL_error(L, "'remove' expects at most 2 
arguments"));
        msg = MAY_LJMP(hlua_checkhttpmsg(L, 1));
 
        if (msg->msg_state < HTTP_MSG_DATA)
@@ -6716,8 +6715,8 @@ __LJMP static int hlua_http_msg_del_data(lua_State *L)
                WILL_LJMP(lua_error(L));
 
        offset = input + output;
-       if (lua_gettop(L) > 2) {
-               offset = MAY_LJMP(luaL_checkinteger(L, 3));
+       if (lua_gettop(L) > 1) {
+               offset = MAY_LJMP(luaL_checkinteger(L, 2));
                if (offset < 0)
                        offset = MAX(0, (int)input + offset);
                offset += output;
@@ -6728,8 +6727,8 @@ __LJMP static int hlua_http_msg_del_data(lua_State *L)
        }
 
        len = output + input - offset;
-       if (lua_gettop(L) == 4) {
-               len = MAY_LJMP(luaL_checkinteger(L, 4));
+       if (lua_gettop(L) == 3) {
+               len = MAY_LJMP(luaL_checkinteger(L, 3));
                if (!len)
                        goto end;
                if (len == -1)
-- 
2.35.1