/* * wslua_file_common.c * * Wireshark's interface to the Lua Programming Language * for file handling related source file internal functions. * * (c) 2014, Hadriel Kaplan * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ /************ * The following is for handling private data for the duration of the file * read_open/read/close cycle, or write_open/write/write_close cycle. * In other words it handles the "priv" member of wtap and wtap_dumper, * but for the Lua script's use. A Lua script can set a Lua table * to CaptureInfo/CaptureInfoConst and have it saved and retrievable this way. * We need to offer that, because there needs to be a way for Lua scripts * to save state for a given file's operations cycle. Since there can be * two files opened at the same time for the same Lua script (due to reload * and other such events), the script can't just have one file state. */ #include "wslua_file_common.h" /* create and set the wtap->priv private data for the file instance */ void create_wth_priv(lua_State* L, wtap *wth) { file_priv_t *priv = (file_priv_t*)g_malloc(sizeof(file_priv_t)); if (wth->priv != NULL) { luaL_error(L, "Cannot create wtap private data because there already is private data"); return; } priv->table_ref = LUA_NOREF; wth->priv = (void*) priv; } /* gets the private data table from wtap */ int get_wth_priv_table_ref(lua_State* L, wtap *wth) { file_priv_t *priv = (file_priv_t*) wth->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot get wtap private data: it is null"); return LUA_NOREF; } /* the following might push a nil, but that's ok */ lua_rawgeti(L, LUA_REGISTRYINDEX, priv->table_ref); return 1; } /* sets the private data to wtap - the table is presumed on top of stack */ int set_wth_priv_table_ref(lua_State* L, wtap *wth) { file_priv_t *priv = (file_priv_t*) wth->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot get wtap private data: it is null"); return 0; } if (lua_isnil(L, -1)){ /* user is setting it nil - ok, de-ref any previous one */ luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); priv->table_ref = LUA_NOREF; return 0; } if (!lua_istable(L, -1)) { luaL_error(L, "The private_table member can only be set to a table or nil"); return 0; } /* if we had a table already referenced, de-ref it first */ if (priv->table_ref != LUA_NOREF) { luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); } priv->table_ref = luaL_ref(L, LUA_REGISTRYINDEX); return 0; } /* remove, deref, and free the wtap->priv data */ void remove_wth_priv(lua_State* L, wtap *wth) { file_priv_t *priv = (file_priv_t*) wth->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot remove wtap private data: it is null"); return; } luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); g_free(wth->priv); wth->priv = NULL; } /* create and set the wtap_dumper->priv private data for the file instance */ void create_wdh_priv(lua_State* L, wtap_dumper *wdh) { file_priv_t *priv = (file_priv_t*)g_malloc(sizeof(file_priv_t)); if (wdh->priv != NULL) { luaL_error(L, "Cannot create wtap_dumper private data because there already is private data"); return; } priv->table_ref = LUA_NOREF; wdh->priv = (void*) priv; } /* get the private data from wtap_dumper */ int get_wdh_priv_table_ref(lua_State* L, wtap_dumper *wdh) { file_priv_t *priv = (file_priv_t*) wdh->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot get wtap_dumper private data: it is null"); return LUA_NOREF; } /* the following might push a nil, but that's ok */ lua_rawgeti(L, LUA_REGISTRYINDEX, priv->table_ref); return 1; } /* sets the private data to wtap - the table is presumed on top of stack */ int set_wdh_priv_table_ref(lua_State* L, wtap_dumper *wdh) { file_priv_t *priv = (file_priv_t*) wdh->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot get wtap private data: it is null"); return 0; } if (lua_isnil(L, -1)){ /* user is setting it nil - ok, de-ref any previous one */ luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); priv->table_ref = LUA_NOREF; return 0; } if (!lua_istable(L, -1)) { luaL_error(L, "The private_table member can only be set to a table or nil"); return 0; } /* if we had a table already referenced, de-ref it first */ if (priv->table_ref != LUA_NOREF) { luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); } priv->table_ref = luaL_ref(L, LUA_REGISTRYINDEX); return 0; } /* remove and deref the wtap_dumper->priv data */ void remove_wdh_priv(lua_State* L, wtap_dumper *wdh) { file_priv_t *priv = (file_priv_t*) wdh->priv; if (!priv) { /* shouldn't be possible */ luaL_error(L, "Cannot remove wtap_dumper private data: it is null"); return; } luaL_unref(L, LUA_REGISTRYINDEX, priv->table_ref); /* we do NOT free wtap_dumper's priv member - wtap_dump_close() free's it */ } /* * Editor modelines - http://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * vi: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */