1 /* Copyright (c) 2010-2019. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 /* SimGrid Lua bindings */
8 #include "lua_private.hpp"
9 #include "simgrid/s4u/Host.hpp"
12 XBT_LOG_NEW_DEFAULT_CATEGORY(lua_host, "Lua Host module");
14 constexpr char HOST_MODULE_NAME[] = "simgrid.host";
15 constexpr char HOST_FIELDNAME[] = "__simgrid_host";
17 /* ********************************************************************************* */
18 /* simgrid.host API */
19 /* ********************************************************************************* */
21 /** @brief Ensures that the pointed stack value is a host userdatum and returns it.
23 * @param L a Lua state
24 * @param index an index in the Lua stack
25 * @return the C host corresponding to this Lua host
27 sg_host_t sglua_check_host(lua_State * L, int index)
29 luaL_checktype(L, index, LUA_TTABLE);
30 lua_getfield(L, index, HOST_FIELDNAME);
31 sg_host_t *pi = (sg_host_t *) luaL_checkudata(L, lua_gettop(L), HOST_MODULE_NAME);
34 XBT_ERROR("luaL_checkudata() returned nullptr");
37 luaL_error(L, "null Host");
42 * @brief Returns a host given its name. This is a lua function.
44 * @param L a Lua state
45 * @return number of values returned to Lua
47 * - Argument 1 (string): name of a host
48 * - Return value (host): the corresponding host will be pushed onto the stack
50 static int l_host_get_by_name(lua_State * L)
52 const char *name = luaL_checkstring(L, 1);
53 lua_remove(L, 1); /* remove the args from the stack */
55 sg_host_t host = sg_host_by_name(name);
56 lua_ensure(host, "No host name '%s' found.", name);
58 lua_newtable(L); /* table */
59 sg_host_t *lua_host = (sg_host_t *) lua_newuserdata(L, sizeof(sg_host_t)); /* table userdatum */
61 luaL_getmetatable(L, HOST_MODULE_NAME); /* table userdatum metatable */
62 lua_setmetatable(L, -2); /* table userdatum */
63 lua_setfield(L, -2, HOST_FIELDNAME); /* table -- put the userdata as field of the table */
69 * @brief Returns the name of a host.
70 * @param L a Lua state
71 * @return number of values returned to Lua
73 * - Argument 1 (host): a host
74 * - Return value (string): name of this host
76 static int l_host_get_name(lua_State * L)
78 sg_host_t ht = sglua_check_host(L, 1);
79 lua_pushstring(L, ht->get_cname());
84 * @brief Returns the number of existing hosts.
85 * @param L a Lua state
86 * @return number of values returned to Lua
88 * - Return value (number): number of hosts
90 static int l_host_number(lua_State * L)
92 xbt_dynar_t hosts = sg_hosts_as_dynar();
93 lua_pushinteger(L, xbt_dynar_length(hosts));
94 xbt_dynar_free(&hosts);
99 * @brief Returns the host given its index.
100 * @param L a Lua state
101 * @return number of values returned to Lua
103 * - Argument 1 (number): an index (1 is the first)
104 * - Return value (host): the host at this index
106 static int l_host_at(lua_State * L)
108 int index = luaL_checkinteger(L, 1);
109 xbt_dynar_t hosts = sg_hosts_as_dynar();
110 sg_host_t host = xbt_dynar_get_as(hosts,index - 1,sg_host_t);// lua indexing start by 1 (lua[1] <=> C[0])
111 lua_newtable(L); /* create a table, put the userdata on top of it */
112 sg_host_t *lua_host = (sg_host_t *) lua_newuserdata(L, sizeof(sg_host_t));
114 luaL_getmetatable(L, HOST_MODULE_NAME);
115 lua_setmetatable(L, -2);
116 lua_setfield(L, -2, HOST_FIELDNAME); /* put the userdata as field of the table */
117 xbt_dynar_free(&hosts);
122 * @brief Returns the value of a host property.
123 * @param L a Lua state
124 * @return number of values returned to Lua
126 * - Argument 1 (host): a host
127 * - Argument 2 (string): name of the property to get
128 * - Return value (string): the value of this property
130 static int l_host_get_property_value(lua_State * L)
132 sg_host_t ht = sglua_check_host(L, 1);
133 const char *prop = luaL_checkstring(L, 2);
134 lua_pushstring(L, sg_host_get_property_value(ht,prop));
139 * @brief Destroys a host.
140 * @param L a Lua state
141 * @return number of values returned to Lua
143 * - Argument 1 (host): the host to destroy
145 static int l_host_destroy(lua_State *L)
147 sg_host_t ht = sglua_check_host(L, 1);
152 static const luaL_Reg host_functions[] = {
153 {"get_by_name", l_host_get_by_name},
154 {"name", l_host_get_name},
155 {"number", l_host_number},
157 {"get_prop_value", l_host_get_property_value},
158 {"destroy", l_host_destroy},
159 // Bypass XML Methods
160 {"set_property", console_host_set_property},
165 * @brief Returns a string representation of a host.
166 * @param L a Lua state
167 * @return number of values returned to Lua
169 * - Argument 1 (userdata): a host
170 * - Return value (string): a string describing this host
172 static int l_host_tostring(lua_State * L)
174 lua_pushfstring(L, "Host :%p", lua_touserdata(L, 1));
178 static const luaL_Reg host_meta[] = {
179 {"__tostring", l_host_tostring},
184 * @brief Registers the host functions into the table simgrid.host.
186 * Also initialize the metatable of the host userdata type.
188 * @param L a lua state
190 void sglua_register_host_functions(lua_State* L)
192 /* create a table simgrid.host and fill it with host functions */
193 lua_getglobal(L, "simgrid"); /* simgrid */
194 luaL_newlib(L, host_functions); /* simgrid simgrid.host */
195 lua_setfield(L, -2, "host"); /* simgrid */
196 lua_getfield(L, -1, "host"); /* simgrid simgrid.host */
198 /* create the metatable for host, add it to the Lua registry */
199 luaL_newmetatable(L, HOST_MODULE_NAME); /* simgrid simgrid.host mt */
201 /* fill the metatable */
202 luaL_setfuncs(L, host_meta, 0); /* simgrid simgrid.host mt */
205 * Copy the table and push it onto the stack.
206 * Required for the lua_setfield call below.
208 lua_getfield(L, -3, "host"); /* simgrid simgrid.host mt simgrid.host */
210 /* metatable.__index = simgrid.host
211 * we put the host functions inside the host userdata itself:
212 * this allows to write my_host:method(args) for
213 * simgrid.host.method(my_host, args) */
214 lua_setfield(L, -2, "__index"); /* simgrid simgrid.host mt */
216 lua_setmetatable(L, -2); /* simgrid simgrid.host */
217 lua_pop(L, 2); /* -- */